Sample records for al eur phys

  1. Introducing False EUR and False EUR exchange rates

    NASA Astrophysics Data System (ADS)

    Ausloos, M.; Ivanova, K.

    2000-10-01

    The Euro ( EUR) is a new currency introduced by the European Community. Its exchange rate is very puzzling. We have invented a false Euro ( FEUR) dating back to 1993 and have derived the exchange rates of the FEUR with respect to currencies not belonging to the EUR, i.e., DKK, CHF, JPY and USD. This allows us to search for correlations between the fluctuations preexisting to the introduction of EUR and present ones in such financial data. The detrended fluctuation analysis ( DFA) statistical method is used. This leads to assume a power-law behavior, i.e., a scaling hypothesis, through an exponent α. The latter has demonstrated its usefulness for the investigations of long-range power-law correlations in several types of financial sequences. Our findings show that the α exponent interestingly characterizes fractional Brownian motion of the currency exchange rates between EUR and DKK over a 25 day interval, and usual Brownian motion otherwise and for the three other investigated exchange rates. We can devise an investment strategy based on the localα technique and obtain appreciable gains for the time being.

  2. Renormalization scheme dependence of the two-loop QCD corrections to the neutral Higgs-boson masses in the MSSM.

    PubMed

    Borowka, S; Hahn, T; Heinemeyer, S; Heinrich, G; Hollik, W

    Reaching a theoretical accuracy in the prediction of the lightest MSSM Higgs-boson mass, [Formula: see text], at the level of the current experimental precision requires the inclusion of momentum-dependent contributions at the two-loop level. Recently two groups presented the two-loop QCD momentum-dependent corrections to [Formula: see text] (Borowka et al., Eur Phys J C 74(8):2994, 2014; Degrassi et al., Eur Phys J C 75(2):61, 2015), using a hybrid on-shell-[Formula: see text] scheme, with apparently different results. We show that the differences can be traced back to a different renormalization of the top-quark mass, and that the claim in Ref. Degrassi et al. (Eur Phys J C 75(2):61, 2015) of an inconsistency in Ref. Borowka et al. (Eur Phys J C 74(8):2994, 2014) is incorrect. We furthermore compare consistently the results for [Formula: see text] obtained with the top-quark mass renormalized on-shell and [Formula: see text]. The latter calculation has been added to the FeynHiggs package and can be used to estimate missing higher-order corrections beyond the two-loop level.

  3. Virtual Compton Scattering and the Generalized Polarizabilities of the Proton

    NASA Astrophysics Data System (ADS)

    Hyde-Wright, Charles E.

    2002-10-01

    The Virtual Compton Scattering (VCS) process: e p arrow e p γ is sensitive to the Electromagnetic Polarizabilities of the proton. As a function of the wavelength of the virtual photon, it is possible to map out the spatial variation of the polarization response. The Low Energy Theorem (P. Guichon et al.,Nucl.Phys.A591:606-638,1995) and the Dispersion Relation formalism (B. Pasquini et al., Eur.Phys.J.A11:185-208,2001), permit the extraction of the electric and magnetic polarizabilities from VCS data up to the two pion production threshold. At Jefferson Lab, we have measured the electric and magnetic polarization response at Q^2 = 1 and 1.7 GeV^2. These complement earlier measurements at Q^2 = 0.33 (J. Roche, et al., Phys.Rev.Lett.85:708,2000) and 0.0 GeV^2 (V. Olmos de Leon, et al., Eur.Phys.J.A10:207-215,2001, B.E. MacGibbon, et al., Phys.Rev.C52:2097-2109,1995). The electric polarization and magnetic responses are very different as a function of distance scale. The electric polarizability falls with Q^2 in accord with the electric form factor of the proton: G_E(Q^2). However, for the magnetic polarizability the data illustrate the strong cancellation of para- and dia-magnetism at all distance scales within the proton.

  4. Are EUR and GBP different words for the same currency?

    NASA Astrophysics Data System (ADS)

    Ivanova, K.; Ausloos, M.

    2002-05-01

    The British Pound (GBP) is not part of the Euro (EUR) monetary system. In order to find out arguments on whether GBP should join the EUR or not correlations are calculated between GBP exchange rates with respect to various currencies: USD, JPY, CHF, DKK, the currencies forming EUR and a reconstructed EUR for the time interval from 1993 till June 30, 2000. The distribution of fluctuations of the exchange rates is Gaussian for the central part of the distribution, but has fat tails for the large size fluctuations. Within the Detrended Fluctuation Analysis (DFA) statistical method the power law behavior describing the root-mean-square deviation from a linear trend of the exchange rate fluctuations is obtained as a function of time for the time interval of interest. The time-dependent exponent evolution of the exchange rate fluctuations is given. Statistical considerations imply that the GBP is already behaving as a true EUR.

  5. Comment on ``Nonlinear gyrokinetic theory with polarization drift'' [Phys. Plasmas 17, 082304 (2010)

    NASA Astrophysics Data System (ADS)

    Leerink, S.; Parra, F. I.; Heikkinen, J. A.

    2010-12-01

    In this comment, we show that by using the discrete particle distribution function the changes of the phase-space volume of gyrocenter coordinates due to the fluctuating E ×B velocity do not explicitly appear in the Poisson equation and the [Sosenko et al., Phys. Scr. 64, 264 (2001)] result is recovered. It is demonstrated that there is no contradiction between the work presented by Sosenko et al. and the work presented by [Wang et al., Phys. Plasmas 17, 082304 (2010)].

  6. Comment on ``Oxidation of alloys containing aluminum and diffusion in Al2O3'' [J. Appl. Phys. 95, 3217 (2004)

    NASA Astrophysics Data System (ADS)

    Åkermark, Torbjörn

    2005-06-01

    The introduction of AlO as the diffusing species can be seen as an attempt to bridge the gap between the two scientific communities: those working on the oxidation of metals and those working on the oxidation of silicon. The attempt is, however, not successful and would have been more successful if the Wagner theory [O. Wagner, Z. Phys. Chem. Abt. B 21, 25 (1993)] would have been used to evaluate the mechanisms. There is also a lack of agreement with the two-stage oxidation experiment, oxidation first in O16 and then in O18. The experimental O18 profile in the oxides formed cannot be explained by the diffusion of AlO, so it is unlikely that AlO is the diffusing species during oxidation.

  7. Comment on “Theoretical analysis of high-field transport in graphene on a substrate” [J. Appl. Phys. 116, 034507 (2014)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tan, Michael L. P.; Arora, Vijay K., E-mail: vijay.arora@wilkes.edu; Department of Electrical Engineering and Physics, Wilkes University, Wilkes-Barre, Pennsylvania 18766

    2014-12-21

    In a recent article, Serov et al. [J. Appl. Phys. 116, 034507 (2014)] claim: “This study represents the first time that the high-field behavior in graphene on a substrate was investigated taking into account intrinsic graphene properties,” ignoring the most recent anisotropic distribution function [V. K. Arora et al., J. Appl. Phys. 112, 114330 (2012)] also published in J. Appl. Phys., targeting the same experimental data [V. E. Dorgan et al., Appl. Phys. Lett. 97, 082112 (2010)]. The claim of Serov et al. of being first is refuted and many shortcomings of the hydrodynamic model for a highly quantum andmore » degenerate graphene nanolayer are pointed out.« less

  8. Kinetic water-bag model of global collisional drift waves and ion temperature gradient instabilities in cylindrical geometry

    NASA Astrophysics Data System (ADS)

    Gravier, E.; Plaut, E.

    2013-04-01

    Collisional drift waves and ion temperature gradient (ITG) instabilities are studied using a linear water-bag kinetic model [P. Morel et al., Phys. Plasmas 14, 112109 (2007)]. An efficient spectral method, already validated in the case of drift waves instabilities [E. Gravier et al., Eur. Phys. J. D 67, 7 (2013)], allows a fast solving of the global linear problem in cylindrical geometry. The comparison between the linear ITG instability properties thus computed and the ones given by the COLUMBIA experiment [R. G. Greaves et al., Plasma Phys. Controlled Fusion 34, 1253 (1992)] shows a qualitative agreement. Moreover, the transition between collisional drift waves and ITG instabilities is studied theoretically as a function of the ion temperature profile.

  9. Impact of Duality Violations on Spectral Sum Rule analyses

    NASA Astrophysics Data System (ADS)

    Catà, Oscar

    2007-02-01

    Recent sum rule analyses on the two-point correlator have led to significant discrepancies in the values found for the OPE condensates, most dramatically in the dimension eight condensate and to a lesser extent in the dimension six one [R. Barate et al., ALEPH Collaboration, Eur. Phys. J. C 4 (1998) 409; K. Ackerstaff et al., OPAL Collaboration, Eur. Phys. J. C 7 (1999) 571, arXiv:hep-ex/9808019; S. Peris, B. Phily and E. de Rafael, Phys. Rev. Lett. 86 (2001) 14, arXiv:hep-ph/0007338; S. Friot, D. Greynat and E. de Rafael, JHEP 0410 (2004) 043, arXiv:hep-ph/0408281; M. Davier, L. Girlanda, A. Hocker and J. Stern, Phys. Rev. D 58 (1998) 096014, arXiv:hep-ph/9802447; B.L. Ioffe and K.N. Zyablyuk, Nucl. Phys. A 687 (2001) 437, arXiv:hep-ph/0010089. K.N. Zyablyuk, Eur. Phys. J. C 38 (2004) 215, arXiv:hep-ph/0404230; J. Bijnens, E. Gamiz and J. Prades, JHEP 0110 (2001) 009, arXiv:hep-ph/0108240; C.A. Dominguez and K. Schilcher, Phys. Lett. B 581 (2004) 193, arXiv:hep-ph/0309285; J. Rojo and J. I. Latorre, JHEP 0401 (2004) 055, arXiv:hep-ph/0401047; V. Cirigliano, E. Golowich and K. Maltman, Phys. Rev. D 68 (2003) 054013, arXiv:hep-ph/0305118; S. Ciulli, C. Sebu, K. Schilcher and H. Spiesberger, Phys. Lett. B 595 (2004) 359, arXiv:hep-ph/0312212. S. Narison, arXiv:hep-ph/0412152]. Precise knowledge of these condensates is of relevance in kaon decays [M. Knecht, S. Peris and E. de Rafael, Phys. Lett. B 457 (1999) 227, arXiv:hep-ph/9812471; J.F. Donoghue and E. Golowich, Phys. Lett. B 478 (2000) 172, arXiv:hep-ph/9911309; M. Knecht, S. Peris and E. de Rafael, Phys. Lett. B 508 (2001) 117, arXiv:hep-ph/0102017] and therefore it seems mandatory to assess the actual impact of what is commonly neglected in spectral sum rules, most prominently the issue of duality violations. We will explicitly compute them in a toy model and show that they are a priori non-negligible.

  10. Entropic uncertainty and measurement reversibility

    NASA Astrophysics Data System (ADS)

    Berta, Mario; Wehner, Stephanie; Wilde, Mark M.

    2016-07-01

    The entropic uncertainty relation with quantum side information (EUR-QSI) from (Berta et al 2010 Nat. Phys. 6 659) is a unifying principle relating two distinctive features of quantum mechanics: quantum uncertainty due to measurement incompatibility, and entanglement. In these relations, quantum uncertainty takes the form of preparation uncertainty where one of two incompatible measurements is applied. In particular, the ‘uncertainty witness’ lower bound in the EUR-QSI is not a function of a post-measurement state. An insightful proof of the EUR-QSI from (Coles et al 2012 Phys. Rev. Lett. 108 210405) makes use of a fundamental mathematical consequence of the postulates of quantum mechanics known as the non-increase of quantum relative entropy under quantum channels. Here, we exploit this perspective to establish a tightening of the EUR-QSI which adds a new state-dependent term in the lower bound, related to how well one can reverse the action of a quantum measurement. As such, this new term is a direct function of the post-measurement state and can be thought of as quantifying how much disturbance a given measurement causes. Our result thus quantitatively unifies this feature of quantum mechanics with the others mentioned above. We have experimentally tested our theoretical predictions on the IBM quantum experience and find reasonable agreement between our predictions and experimental outcomes.

  11. Pion distribution amplitude from Euclidean correlation functions

    NASA Astrophysics Data System (ADS)

    Bali, Gunnar S.; Braun, Vladimir M.; Gläßle, Benjamin; Göckeler, Meinulf; Gruber, Michael; Hutzler, Fabian; Korcyl, Piotr; Lang, Bernhard; Schäfer, Andreas; Wein, Philipp; Zhang, Jian-Hui

    2018-03-01

    Following the proposal in (Braun and Müller. Eur Phys J C55:349, 2008), we study the feasibility to calculate the pion distribution amplitude (DA) from suitably chosen Euclidean correlation functions at large momentum. In our lattice study we employ the novel momentum smearing technique (Bali et al. Phys Rev D93:094515, 2016; Bali et al. Phys Lett B774:91, 2017). This approach is complementary to the calculations of the lowest moments of the DA using the Wilson operator product expansion and avoids mixing with lower dimensional local operators on the lattice. The theoretical status of this method is similar to that of quasi-distributions (Ji. Phys Rev Lett 110:262002, 2013) that have recently been used in (Zhang et al. Phys Rev D95:094514, 2017) to estimate the twist two pion DA. The similarities and differences between these two techniques are highlighted.

  12. Comment on ‘On the realisation of quantum Fisher information’

    NASA Astrophysics Data System (ADS)

    Olendski, O.

    2017-05-01

    It is shown that calculation of the momentum Fisher information of the quasi-one-dimensional hydrogen atom recently presented by Saha et al (2017 Eur. J. Phys. 38 025103) is wrong. A correct derivation is provided and its didactical advantages and scientific significances are highlighted.

  13. Kinetic water-bag model of global collisional drift waves and ion temperature gradient instabilities in cylindrical geometry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gravier, E.; Plaut, E.

    2013-04-15

    Collisional drift waves and ion temperature gradient (ITG) instabilities are studied using a linear water-bag kinetic model [P. Morel et al., Phys. Plasmas 14, 112109 (2007)]. An efficient spectral method, already validated in the case of drift waves instabilities [E. Gravier et al., Eur. Phys. J. D 67, 7 (2013)], allows a fast solving of the global linear problem in cylindrical geometry. The comparison between the linear ITG instability properties thus computed and the ones given by the COLUMBIA experiment [R. G. Greaves et al., Plasma Phys. Controlled Fusion 34, 1253 (1992)] shows a qualitative agreement. Moreover, the transition betweenmore » collisional drift waves and ITG instabilities is studied theoretically as a function of the ion temperature profile.« less

  14. EUReKA! A Conceptual Model of Emotion Understanding

    PubMed Central

    Castro, Vanessa L.; Cheng, Yanhua; Halberstadt, Amy G.; Grühn, Daniel

    2015-01-01

    The field of emotion understanding is replete with measures, yet lacks an integrated conceptual organizing structure. To identify and organize skills associated with the recognition and knowledge of emotions, and to highlight the focus of emotion understanding as localized in the self, in specific others, and in generalized others, we introduce the conceptual framework of Emotion Understanding in Recognition and Knowledge Abilities (EUReKA). We then categorize fifty-six existing methods of emotion understanding within this framework to highlight current gaps and future opportunities in assessing emotion understanding across the lifespan. We hope the EUReKA model provides a systematic and integrated framework for conceptualizing and measuring emotion understanding for future research. PMID:27594904

  15. Response to "Comment on `Solitonic and chaotic behaviors for the nonlinear dust-acoustic waves in a magnetized dusty plasma'" [Phys. Plasmas 24, 094701 (2017)

    NASA Astrophysics Data System (ADS)

    Zhen, Hui-Ling; Tian, Bo; Xie, Xi-Yang; Wu, Xiao-Yu; Wen, Xiao-Yong

    2018-02-01

    On our previous construction [H. L. Zhen et al., Phys. Plasmas 23, 052301 (2016)] of the soliton solutions of a model describing the dynamics of the dust particles in a weakly ionized, collisional dusty plasma comprised of the negatively charged cold dust particles, hot ions, hot electrons, and stationary neutrals in the presence of an external static magnetic field, Ali et al. [Phys. Plasmas 24, 094701 (2017)] have commented that there exists a different form of Eq. (4) from that shown in Zhen et al. [Phys. Plasmas 23, 052301 (2016)] and that certain interesting phenomena with the dust neutral collision frequency ν0>0 are ignored in Zhen et al. [Phys. Plasmas 23, 052301 (2016)]. In this Reply, according to the transformation given by the Ali et al. [Phys. Plasmas 24, 094701 (2017)] comment, we present some one-, two-, and N-soliton solutions which have not been obtained in the Ali et al. [Phys. Plasmas 24, 094701 (2017)] comment. We point out that our previous solutions in Zhen et al. [Phys. Plasmas 23, 052301 (2016)] are still valid because of the similarity between the two dispersion relations of previous solutions in Zhen et al. [Phys. Plasmas 23, 052301 (2016)] and the solutions presented in this Reply. Based on our soliton solutions in this Reply, it is found that the soliton amplitude is inversely related to Zd and B0, but positively related to md and α, where α refers to the coefficient of the nonlinear term, Zd and md are the charge number and mass of a dust particle, respectively, B0 represents the strength of the external static magnetic field. We also find that the two solitons are always in parallel during the propagation.

  16. Comment on ``Turbulent equipartition theory of toroidal momentum pinch'' [Phys. Plasmas 15, 055902 (2008)

    NASA Astrophysics Data System (ADS)

    Peeters, A. G.; Angioni, C.; Strintzi, D.

    2009-03-01

    The comment addresses questions raised on the derivation of the momentum pinch velocity due to the Coriolis drift effect [A. G. Peeters et al., Phys. Rev. Lett. 98, 265003 (2007)]. These concern the definition of the gradient, and the scaling with the density gradient length. It will be shown that the turbulent equipartition mechanism is included within the derivation using the Coriolis drift, with the density gradient scaling being the consequence of drift terms not considered in [T. S. Hahm et al., Phys. Plasmas 15, 055902 (2008)]. Finally the accuracy of the analytic models is assessed through a comparison with the full gyrokinetic solution.

  17. Fluctuations and symmetries in two-dimensional active gels.

    PubMed

    Sarkar, N; Basu, A

    2011-04-01

    Motivated by the unique physical properties of biological active matter, e.g., cytoskeletal dynamics in eukaryotic cells, we set up effective two-dimensional (2d) coarse-grained hydrodynamic equations for the dynamics of thin active gels with polar or nematic symmetries. We use the well-known three-dimensional (3d) descriptions (K. Kruse et al., Eur. Phys. J. E 16, 5 (2005); A. Basu et al., Eur. Phys. J. E 27, 149 (2008)) for thin active-gel samples confined between parallel plates with appropriate boundary conditions to derive the effective 2d constitutive relations between appropriate thermodynamic fluxes and generalised forces for small deviations from equilibrium. We consider three distinct cases, characterised by spatial symmetries and boundary conditions, and show how such considerations dictate the structure of the constitutive relations. We use these to study the linear instabilities, calculate the correlation functions and the diffusion constant of a small tagged particle, and elucidate their dependences on the activity or nonequilibrium drive.

  18. Summary of PhysPAG Activity

    NASA Astrophysics Data System (ADS)

    Nousek, John A.

    2014-01-01

    The Physics of the Cosmos Program Analysis Group (PhysPAG) is responsible for solicitiing and coordinating community input for the development and execution of NASA's Physics of the Cosmos (PCOS) program. In this session I will report on the activity of the PhysPAG, and solicit community involvement in the process of defining PCOS objectives, planning SMD architecture, and prioritizing PCOS activities. I will also report on the activities of the PhysPAG Executive Committee, which include the chairs of the Science Analysis Groups/ Science Interest Groups which fall under the PhysPAG sphere of interest. Time at the end of the presentation willl be reserved for questions and discussion from the community.

  19. Establishment of the Ph. Eur. erythropoietin chemical reference substance batch 1.

    PubMed

    Burns, C; Bristow, A F; Buchheit, K H; Daas, A; Wierer, M; Costanzo, A

    2015-01-01

    The Erythropoietin (EPO) European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) batch 3 was calibrated in 2006 by in vivo bioassay and was used as a reference preparation for these assays as well as for the physicochemical methods in the Ph. Eur. monograph Erythropoietin concentrated solution (1316). In order to avoid the frequent replacement of this standard and thus reduce the use of animals, a new EPO Chemical Reference Substance (CRS) was established to be used solely for the physicochemical methods. Here we report the outcome of a collaborative study aimed at demonstrating the suitability of the candidate CRS (cCRS) as a reference for the physicochemical methods in the Ph. Eur. monograph. Results from the study demonstrated that for the physicochemical methods currently required in the monograph (capillary zone electrophoresis (CZE), polyacrylamide gel electrophoresis (PAGE)/immunoblotting and peptide mapping), the cCRS is essentially identical to the existing BRP. However, data also indicated that, for the physicochemical methods under consideration for inclusion in a revised monograph (test for oxidised forms and glycan mapping), the suitability of the cCRS as a reference needs to be confirmed with additional work. Further to completion of the study, the Ph. Eur. Commission adopted the cCRS as "Erythropoietin for physicochemical tests CRS batch 1" to be used for CZE, PAGE/immunoblotting and peptide mapping.

  20. Comment on 'Three-dimensional numerical investigation of electron transport with rotating spoke in a cylindrical anode layer Hall plasma accelerator'[Phys. Plasmas 19, 073519 (2012)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ellison, C. L.; Parker, J. B.; Raitses, Y.

    The oscillation behavior described by Tang et al.[Phys. Plasmas 19, 073519 (2012)] differs too greatly from previous experimental and numerical studies to claim observation of the same phenomenon. Most significantly, the rotation velocity by Tang et al.[Phys. Plasmas 19, 073519 (2012)] is three orders of magnitude larger than that of typical 'rotating spoke' phenomena. Several physical and numerical considerations are presented to more accurately understand the numerical results of Tang et al.[Phys. Plasmas 19, 073519 (2012)] in light of previous studies.

  1. Summary of PhysPAG Activities

    NASA Astrophysics Data System (ADS)

    Ritz, Steven M.

    2013-01-01

    The Physics of the Cosmos (PCOS) Program Analysis Group (PhysPAG) provides an important interface between the scientific community and NASA in matters related to PCOS objectives, and also provides opportunities for community discussions. An Executive Committee facilitates the work of several subgroups, including an Inflation Probe Science Analysis Group (IPSAG), an X-ray group (XRSAG) , a gamma-ray,group (GRSAG), a gravitational wave group (GWSAG), and a cosmic-ray group (CRSAG). In addition to identifying opportunities and issues, these groups also help articulate technology needs. Membership in all the SAGs is completely open, with information and newsletter signups available on the PhysPAG pages at the PCOS program website. The PhysPAG reports to the Astrophysics Subcommittee of the NASA Advisory Council. A summary of PhysPAG activities will be given, along with time for questions and discussion.

  2. Crossover of cation partitioning in olivines: a combination of ab initio and Monte Carlo study

    NASA Astrophysics Data System (ADS)

    Chatterjee, Swastika; Bhattacharyya, Sirshendu; Sengupta, Surajit; Saha-Dasgupta, Tanusri

    2011-04-01

    We report studies based on a combination of ab initio electronic structure and Monte Carlo (MC) technique on the problem of cation partitioning among inequivalent octahedral sites, M1 and M2 in mixed olivines containing Mg2+ and Fe2+ ions. Our MC scheme uses interactions derived out of ab initio, density functional calculations carried out on measured crystal structure data. Our results show that there is no reversal of the preference of Fe for M1 over M2 as a function of temperature. Our findings do not agree with the experimental findings of Redfern et al. (Phys Chem Miner 27:630-637, 2000), but are in agreement with those of Heinemann et al. (Eur J Mineral 18:673-689, 2006) and Morozov et al. (Eur J Mineral 17:495-500, 2005).

  3. Analysis of bubbles and crashes in the TRY/USD, TRY/EUR, TRY/JPY and TRY/CHF exchange rate within the scope of econophysics

    NASA Astrophysics Data System (ADS)

    Deviren, Bayram; Kocakaplan, Yusuf; Keskin, Mustafa; Balcılar, Mehmet; Özdemir, Zeynel Abidin; Ersoy, Ersan

    2014-09-01

    In this study, we analyze the Turkish Lira/US Dollar (TRY/USD), Turkish Lira/Euro (TRY/EUR), Turkish Lira/Japanese Yen (TRY/JPY) and Turkish Lira/Swiss Franc (TRY/CHF) exchange rates in the global financial crisis period to detect the bubbles and crashes in the TRY by using a mathematical methodology developed by Watanabe et al. (2007). The methodology defines the bubbles and crashes in financial market price fluctuations by considering an exponential fitting of the associated data. This methodology is applied to detect the bubbles and crashes in the TRY/USD, TRY/EUR, TRY/JPY and TRY/CHF exchange rates from January, 1, 2005 to December, 20, 2013. In this mathematical methodology, the whole period of bubbles and crashes can be determined purely from past data, and the start of bubbles and crashes can be identified even before its bursts. In this way, the periods of bubbles and crashes in the TRY/USD, TRY/EUR, TRY/JPY and TRY/CHF are determined, and the beginning and end points of these periods are detected. The results show that the crashes in the TRY/CHF exchange rate are commonly finished earlier than in the other exchange rates; hence it is probable that the crashes in the other exchange rates would be finished soon when the crashes in the TRY/CHF exchange rate ended. We also find that the periods of crashes in the TRY/EUR exchange rate take longer time than in the other exchange rates. This information can be used in risk management and/or speculative gain. The crashes' periods in the TRY/EUR and TRY/USD exchange rates are observed to be relatively longer than in the other exchange rates.

  4. On the Heat Transfer through a Solid Slab Heated Uniformly and Continuously on One of Its Surfaces

    ERIC Educational Resources Information Center

    Marin, E.; Lara-Bernal, A.; Calderon, A.; Delgado-Vasallo, O.

    2011-01-01

    Some peculiarities of the heat transfer through a sample that is heated by the superficial absorption of light energy under continuous uniform illumination are discussed. We explain, using a different approach to that presented in a recent article published in this journal (Salazar "et al" 2010 "Eur. J. Phys." 31 1053-9), that the front surface of…

  5. One-Loop Calculations and Detailed Analysis of the Localized Non-Commutative p^{-2} U(1) Gauge Model

    NASA Astrophysics Data System (ADS)

    Blaschke, Daniel N.; Rofner, Arnold; Sedmik, René I. P.

    2010-05-01

    This paper carries forward a series of articles describing our enterprise to construct a gauge equivalent for the θ-deformed non-commutative p-2 model originally introduced by Gurau et al. [Comm. Math. Phys. 287 (2009), 275-290]. It is shown that breaking terms of the form used by Vilar et al. [J. Phys. A: Math. Theor. 43 (2010), 135401, 13 pages] and ourselves [Eur. Phys. J. C: Part. Fields 62 (2009), 433-443] to localize the BRST covariant operator (D2θ2D2)-1 lead to difficulties concerning renormalization. The reason is that this dimensionless operator is invariant with respect to any symmetry of the model, and can be inserted to arbitrary power. In the present article we discuss explicit one-loop calculations, and analyze the mechanism the mentioned problems originate from.

  6. Response to ``Comment on `Slow Debye-type peak observed in the dielectric response of polyalcohols' '' [J. Chem. Phys. 134, 037101 (2011)

    NASA Astrophysics Data System (ADS)

    Bergman, R.; Jansson, H.; Swenson, J.

    2011-01-01

    In our recent article [R. Bergman et al., J. Chem. Phys. 132, 044504 (2010)] we investigated some polyalcohols, i.e., glycerol, xylitol, and sorbitol by dielectric spectroscopy. In the study, a low-frequency peak of Debye character that normally is hidden by the large low-frequency dispersion due to conductivity was revealed by analyzing the real part of the permittivity and by using a thin Teflon film to suppress the low-frequency dispersion. We agree with the comment by Paluch et al. [J. Chem. Phys. 134, 037101 (2011)] that the Teflon film setup will indeed create a peak due to the dc conductivity. However, due to the fact that the location of the peak was almost identical in measurement with and without Teflon, we unfortunately mainly showed the data measured with Teflon, despite that it could also be observed in the real part of the permittivity without using the Teflon setup, as shown in our original article [R. Bergman et al., J. Chem. Phys. 132, 044504 (2010)]. Here, we show that the low-frequency peak of Debye character can also be observed by subtracting the dc conductivity. Furthermore, we show that the modulus representation used in Paluch et al. [J. Chem. Phys. 134, 037101 (2011).] is also not suitable for detecting processes hidden by the conductivity.

  7. Comment on ‘The paradoxical zero reflection at zero energy’

    NASA Astrophysics Data System (ADS)

    van Dijk, W.; Nogami, Y.

    2017-05-01

    We point out that the anomalous threshold effect in one dimension occurs when the reflection probability at zero energy R(0) has some other value than unity, rather than R(0)=0 or R(0)\\ll 1 as implied by Ahmed et al in their paper entitled ‘The paradoxical zero reflection at zero energy’ (2017 Eur. J. Phys. 38 025401).

  8. Alternative Tsunami Models

    ERIC Educational Resources Information Center

    Tan, A.; Lyatskaya, I.

    2009-01-01

    The interesting papers by Margaritondo (2005 "Eur. J. Phys." 26 401) and by Helene and Yamashita (2006 "Eur. J. Phys." 27 855) analysed the great Indian Ocean tsunami of 2004 using a simple one-dimensional canal wave model, which was appropriate for undergraduate students in physics and related fields of discipline. In this paper, two additional,…

  9. Research-based resources on PhysPort

    NASA Astrophysics Data System (ADS)

    Sayre, Eleanor

    2017-01-01

    PhysPort (http://physport.org) is a website that supports physics faculty in implementing research-based teaching practices in their classrooms. We provide expert recommendations and practical information about teaching methods and assessment. The PhysPort Data Explorer is an intuitive online tool for physics faculty to analyze their assessment data. Faculty upload their students' responses using our secure interface. The Data Explorer matches their pre/post data, scores it, compares it to national data, and graphs it in an interactive and intuitive manner. The Periscope collection on Physport brings together classroom video of students working groups with professional development materials for faculty, pre-service teachers, and learning assistants. To support PhysPort's development efforts, we conduct research on faculty needs around teaching and assessment, secondary analysis of published PER studies, and primary analysis of assessment data. In this talk, I'll introduce some of PhysPort's research-based resources and the research results which support them.

  10. Response to "Comment on `Magnetic geometry and physics of advanced divertors: The X-divertor and the snowflake' " [Phys. Plasmas 21, 054701 (2014)

    NASA Astrophysics Data System (ADS)

    Kotschenreuther, Mike; Valanju, Prashant; Covele, Brent; Mahajan, Swadesh

    2014-05-01

    Relying on coil positions relative to the plasma, the "Comment on `Magnetic geometry and physics of advanced divertors: The X-divertor and the snowflake' " [Phys. Plasmas 21, 054701 (2014)], emphasizes a criterion for divertor characterization that was critiqued to be ill posed [M. Kotschenreuther et al., Phys. Plasmas 20, 102507 (2013)]. We find that no substantive physical differences flow from this criteria. However, using these criteria, the successful NSTX experiment by Ryutov et al. [Phys. Plasmas 21, 054701 (2014)] has the coil configuration of an X-divertor (XD), rather than a snowflake (SF). On completing the divertor index (DI) versus distance graph for this NSTX shot (which had an inexplicably missing region), we find that the DI is like an XD for most of the outboard wetted divertor plate. Further, the "proximity condition," used to define an SF [M. Kotschenreuther et al., Phys. Plasmas 20, 102507 (2013)], does not have a substantive physics basis to override metrics based on flux expansion and line length. Finally, if the criteria of the comment are important, then the results of NSTX-like experiments could have questionable applicability to reactors.

  11. Long-term Records of Trace Metal Elements in Core Sediments: Anthropogenic Impacts in The Eure River Watershed

    NASA Astrophysics Data System (ADS)

    Gardes, T.; Debret, M.; Copard, Y.; Patault, E.; Deloffre, J.; Marcotte, S.; Develle, A. L.; Sabatier, P.; Chaumillon, E.; Coulombier, T.; Revillon, S.; Nizou, J.; Laberdesque, Y.; Koltalo, F.

    2017-12-01

    The Martot Dam is located in the Eure River Watershed (Normandy, France), few hundred meters upstream the Eure-Seine Rivers confluence. In the context of the European Water Framework Directive (2000/60/EC), the French Authorities planned to remove this dam in 2017. Nevertheless, impacts of the removal remain poorly studied. Classically, dam blocked sedimentary transfers downstream, but here, sediments are not blocked behind the dam but stored three hundred meters upstream in a hydraulic annex, called the Martot Pond. Furthermore, this pond is submitted to the tidal flow from the Seine Estuary despite the Martot Dam. The aim of the study is to evaluate the dam removal impacts on sedimentary transfers and re-suspension of contaminated sediments stored in the Martot Pond and the Eure River's channel. Concerning past transfers and sediments accumulation in the Eure River Watershed, sedimentary archives have been cored, before dam removal, at the Martot Pond and the Les Damps Pond (located 10km upstream the latter). Dating of sedimentary cores for both ponds indicates a sedimentation rate around 1 cm y-1. Trace metal elements quantification showed a wide metallic contamination with highest concentrations evidenced during the 1950-1960's (As: 13-22 mg kg-1; Cd: 40-55 mg kg-1; Cr: 170-210 mg kg-1; Cu: 400-490 mg kg-1; Hg: 2.3 mg kg-1; Mn: 1,280-2,200 mg kg-1; Ni: 64-75 mg kg-1; Zn: 905-990 mg kg-1) and the 1990-2000's (Cr: 95-215 mg kg-1; Ni: 100 mg kg-1; Pb: 670-855 mg kg-1). These variations of concentrations along cores can be associated with industrial past of the Eure River Watershed and sources of contamination can be identified. Thereby, Zn, Ni or Hg contamination could be associated with wastes of battery factory released in the Eure River during the economic recovery, while Pb contamination is linked to the activities of a cathode-ray tubes factory. Metals quantification in core materials highlighted anthropogenic impacts in the Eure River Watershed. These

  12. One-loop light-cone QCD, effective action for reggeized gluons and QCD RFT calculus

    NASA Astrophysics Data System (ADS)

    Bondarenko, S.; Lipatov, L.; Pozdnyakov, S.; Prygarin, A.

    2017-09-01

    The effective action for reggeized gluons is based on the gluodynamic Yang-Mills Lagrangian with external current for longitudinal gluons added, see Lipatov (Nucl Phys B 452:369, 1995; Phys Rep 286:131, 1997; Subnucl Ser 49:131, 2013; Int J Mod Phys Conf Ser 39:1560082, 2015; Int J Mod Phys A 31(28/29):1645011, 2016; EPJ Web Conf 125:01010, 2016). On the base of classical solutions, obtained in Bondarenko et al. (Eur Phys J C 77(8):527, 2017), the one-loop corrections to this effective action in light-cone gauge are calculated. The RFT calculus for reggeized gluons similarly to the RFT introduced in Gribov (Sov Phys JETP 26:414, 1968) is proposed and discussed. The correctness of the results is verified by calculation of the propagators of A+ and A- reggeized gluons fields and application of the obtained results is discussed as well.

  13. Comment on ``Equation of state of aluminum nitride and its shock response'' [J. Appl. Phys. 76, 4077 (1994)

    NASA Astrophysics Data System (ADS)

    Rosenberg, Z.; Brar, N. S.

    1995-11-01

    A recent article by Dandekar, Abbate, and Frankel [J. Appl. Phys. 76, 4077 (1994)] reviews existing data on high-pressure properties of aluminum nitride (AlN) in an effort to build an equation of state for this material. A rather large portion of that article is devoted to the shear strength of AlN and, in particular, to our data of 1991 with longitudinal and lateral stress gauges [Z. Rosenberg, N. S. Brar, and S. J. Bless, J. Appl. Phys. 70, 167 (1991)]. Since our highest data point has an error of 1 GPa, much of the discussion and conclusions of Dandekar and co-workers are not relevant once this error in data reduction is corrected. We also discuss the relevance of our shear strength data for various issues, such as the phase transformation of AlN at 20 GPa and the general shape of Hugoniot curves for brittle solids.

  14. Summary of PhysPAG Activities

    NASA Astrophysics Data System (ADS)

    Ritz, Steven M.

    2012-01-01

    The Physics of the Cosmos (PCOS) Program Analysis Group (PhysPAG) provides an important interface between the scientific community and NASA in matters related to PCOS objectives. An Executive Committee facilitates the work of several subgroups, including a Technology Science Analysis Group and an Inflation Probe Science Analysis Group. Work is also starting in areas of X-ray, gamma-ray, and gravitational wave astrophysics. The PAG reports to the Astrophysics Subcommittee of the NASA Advisory Council. A summary of PhysPAG activities will be given, along with time for questions and discussion.

  15. Comment on 'Effects of magnetic field gradient on ion beam current in cylindrical Hall ion source' [J. Appl. Phys. 102, 123305 (2007)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Raitses, Y.; Smirnov, A.; Fisch, N. J.

    It is argued that the key difference in the cylindrical Hall thruster (CHT) as compared to the end-Hall ion source cannot be exclusively attributed to the magnetic field topology [Tang et al., J. Appl. Phys. 102, 123305 (2007)]. With a similar mirror-type topology, the CHT configuration provides the electric field with nearly equipotential magnetic field surfaces and a better suppression of the electron cross-field transport, as compared to both the end-Hall ion source and the cylindrical Hall ion source of [Tang et al., J. Appl. Phys. 102, 123305 (2007)].

  16. A concise introduction to Colombeau generalized functions and their applications in classical electrodynamics

    NASA Astrophysics Data System (ADS)

    Gsponer, Andre

    2009-01-01

    The objective of this introduction to Colombeau algebras of generalized functions (in which distributions can be freely multiplied) is to explain in elementary terms the essential concepts necessary for their application to basic nonlinear problems in classical physics. Examples are given in hydrodynamics and electrodynamics. The problem of the self-energy of a point electric charge is worked out in detail: the Coulomb potential and field are defined as Colombeau generalized functions, and integrals of nonlinear expressions corresponding to products of distributions (such as the square of the Coulomb field and the square of the delta function) are calculated. Finally, the methods introduced in Gsponer (2007 Eur. J. Phys. 28 267, 2007 Eur. J. Phys. 28 1021 and 2007 Eur. J. Phys. 28 1241), to deal with point-like singularities in classical electrodynamics are confirmed.

  17. Erratum: Erratum to: A study of vorticity formation in high energy nuclear collisions

    NASA Astrophysics Data System (ADS)

    Becattini, F.; Inghirami, G.; Rolando, V.; Beraudo, A.; Del Zanna, L.; De Pace, A.; Nardi, M.; Pagliara, G.; Chandra, V.

    2018-05-01

    Due to an oversight of ours in proofreading and a communication problem with the publisher, the figures published in F. Becattini et al. Eur. Phys. J. C (2015) 75: 406 were not correct. This Erratum contains the correct figures as in arXiv 1501.04468v2, submitted on March 12 2015, and the post-publication version arXiv 1501.04468v3, submitted on August 17 2015.

  18. Comment on ‘Towards addressing transient learning challenges in undergraduate physics: an example from electrostatics’

    NASA Astrophysics Data System (ADS)

    Kwang-Hua, Chu Rainer

    2016-11-01

    We make some crucial remarks about the recent presentation by Fredlund et al (2015 Eur. J. Phys. 36 055002) considering the tutorial problem raised therein. After working out the velocity of the electron (we also included the role of image charges or induced charges) as it strikes the (conducting) metal sphere, we found the velocity value is already near the relativistic regime. The latter then encounters the open issue; to obtain a classical equation of motion of a point charge for which Yaghjian (2008 Phys. Rev. E 78 046606) has mentioned the following difficulty: the electrostatic energy of formation and thus the electrostatic mass of a point charge is infinite.

  19. Response to 'Comment on 'Continuum modes in rotating plasmas: General equations and continuous spectra for large aspect ratio tokamaks' '[Phys. Plasmas 19, 064701 (2012)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lakhin, V. P.; Ilgisonis, V. I.; Peoples' Friendship University, 3 Ordzhonikidze St., Moscow 117198

    2012-06-15

    The equations for the continuous spectra derived in our paper [V. P. Lakhin and V. I. Ilgisonis, Phys. Plasmas 18, 092103 (2011)] can be reduced to the matrix form used by Goedbloed et al.[Phys. Plasmas 11, 28 (2004)]. It is shown that the assumptions made in our paper provide the elliptic flow regime and guarantee the existence of plasma equilibrium with nested magnetic surfaces of circular cross-section. The new results on magnetohydrodynamic instabilities of such tokamak equilibria obtained in our paper but absent in the paper by Goedbloed et al. are emphasized.

  20. Collaborative study for the calibration of the Ph. Eur. prekallikrein activator in albumin BRP batches 4, 5 and 6.

    PubMed

    Lackner, F; Daas, A; Terao, E

    2015-01-01

    An international collaborative study was organised by the European Directorate for the Quality of Medicines & HealthCare (EDQM, Council of Europe) to calibrate replacement batches for the current European Pharmacopoeia (Ph. Eur.) prekallikrein activator (PKA) in albumin biological reference preparation (BRP), whose stocks were dwindling. The study was run in the framework of the Biological Standardisation Programme (BSP) of the Council of Europe and the European Union (EU) Commission. Twenty three laboratories from official medicines control authorities and manufacturers in Europe and outside Europe took part in the study. Three candidate replacement batches were produced from the same material as the one used for the World Health Organization (WHO) 2(nd) International Standard (IS) for PKA in albumin (02/168) and the Ph. Eur. PKA in albumin BRP batches 1, 2 and 3. Participants were requested to evaluate the candidate batches against the current WHO IS using their routine assay method. The Ph. Eur. PKA in albumin BRP batch 3 (BRP3) was also included in the test panel to ensure the continuity of the consecutive BRP batches. The study confirmed the stability of the PKA content of the current BRP3. The candidate batches were found to be comparable. Previous data on the starting material support its high stability. Thermal stress study on the candidate batches confirmed the stability of their PKA activity. The Commission of the Ph. Eur. officially adopted in November 2013 the 3 candidate batches as Ph. Eur. PKA in albumin BRP batches 4, 5 and 6 with an assigned content of 38 IU/vial. The activity of the 3 new batches of Ph. Eur. PKA in albumin BRP will be regularly monitored.

  1. TMD parton distributions based on three-body decay functions in NLL order of QCD

    NASA Astrophysics Data System (ADS)

    Tanaka, Hidekazu

    2015-04-01

    Three-body decay functions in space-like parton branches are implemented to evaluate transverse-momentum-dependent (TMD) parton distribution functions in the next-to-leading logarithmic (NLL) order of quantum chromodynamics (QCD). Interference contributions due to the next-to-leading-order terms are taken into account for the evaluation of the transverse momenta in initial state parton radiations. Some properties of the decay functions are also examined. As an example, the calculated results are compared with those evaluated by an algorithm proposed in [M. A. Kimber, A. D. Martin, and M. G. Ryskin, Eur. Phys. J. C 12, 655 (2000)], [M. A. Kimber, A. D. Martin, and M. G. Ryskin, Phys. Rev. D 63, 11402 (2001)], [G. Watt, A. D. Martin, and M. G. Ryskin, Eur. Phys. J. C 31, 73 (2003)], and [A. D. Martin, M. G. Ryskin, and G. Watt, Eur. Phys. J. C 66, 167 (2010)], in which the TMD parton distributions are defined based on the k_t-factorization method with angular ordering conditions due to interference effects.

  2. Comment on “Surface electromagnetic wave equations in a warm magnetized quantum plasma” [Phys. Plasmas 21, 072114 (2014)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moradi, Afshin, E-mail: a.moradi@kut.ac.ir

    2016-07-15

    In a recent article [C. Li et al., Phys. Plasmas 21, 072114 (2014)], Li et al. studied the propagation of surface waves on a magnetized quantum plasma half-space in the Voigt configuration (in this case, the magnetic field is parallel to the surface but is perpendicular to the direction of propagation). Here, we present a fresh look at the problem and obtain a new form of dispersion relation of surface waves of the system. We find that our new dispersion relation does not agree with the result obtained by Li et al.

  3. Revision of 'Cumulative effect of the filamentation and Weibel instabilities in counterstreaming thermal plasmas' [Phys. Plasmas 13, 102107 (2006)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Stockem, A.; Lazar, M.; Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon

    2008-01-15

    Dispersion formalism reported in Lazar et al. [Phys. Plasmas 13, 102107 (2006)] is affected by errors due to the misfitting of the distribution function (1) used to interpret the counterstreaming plasmas, with the general dispersion relations (4) and (5), where distribution function (1) has been inserted to find the unstable solutions. The analytical approach is reviewed here, providing a correct analytical and numerical description for the cumulative effect of filamentation and Weibel instabilities arising in initially counterstreaming plasmas with temperature anisotropies. The growth rates are plotted again, and for the cumulative mode, they are orders of magnitude larger than thosemore » obtained in Lazar et al. [Phys. Plasmas 13, 102107 (2006)]. Physically, this can be understood as an increasing of the efficiency of magnetic field generation, and rather enhances the potential role of magnetic instabilities for the fast magnetization scenario in astrophysical applications.« less

  4. Physics of the Cosmos Program Analysis Group (PhysPAG) Report

    NASA Astrophysics Data System (ADS)

    Nousek, John A.

    2015-01-01

    The Physics of the Cosmos Program Analysis Group (PhysPAG) serves as a forum for soliciting and coordinating input and analysis from the scientific community in support of the PCOS program objectives. I will outline the activities of the PhysPAG over the past year, since the last meeting during the AAS meeting in National Harbor, and mention the activities of the PhysPAG related Scientific Interest Groups.

  5. Localization of observables in the Rindler wedge

    NASA Astrophysics Data System (ADS)

    Asorey, M.; Balachandran, A. P.; Marmo, G.; de Queiroz, A. R.

    2017-11-01

    One of the striking features of QED is that charged particles create a coherent cloud of photons. The resultant coherent state vectors of photons generate a nontrivial representation of the localized algebra of observables that do not support a representation of the Lorentz group: Lorentz symmetry is spontaneously broken. We show in particular that Lorentz boost generators diverge in this representation, a result shown also by Balachandran et al. [Eur. Phys. J. C 75, 89 (2015), 10.1140/epjc/s10052-015-3305-0] (see also the work by Balachandran et al. [Mod. Phys. Lett. A 28, 1350028 (2013), 10.1142/S0217732313500284]. Localization of observables, for example in the Rindler wedge, uses Poincaré invariance in an essential way [Int. J. Geom. Methods Mod. Phys. 14, 1740008 (2017)., 10.1142/S0219887817400084]. Hence, in the presence of charged fields, the photon observables cannot be localized in the Rindler wedge. These observations may have a bearing on the black hole information loss paradox, as the physics in the exterior of the black hole has points of resemblance to that in the Rindler wedge.

  6. Controlling Self-Assembly in Al(110) Homoepitaxy

    NASA Astrophysics Data System (ADS)

    Tiwary, Yogesh; Fichthorn, Kristen

    2010-03-01

    Homoepitaxial growth on Al(110) exhibits nanoscale self-assembly into huts with well-defined (100) and (111) facets [1]. Although some of the diffusion mechanisms underlying this kinetic self-assembly were identified and incorporated into a two-dimensional model [2], we used density-functional theory (DFT) to identify many other mechanisms that are needed to describe the three-dimensional assembly seen experimentally [3]. We developed a three-dimensional kinetic Monte Carlo (KMC) model of Al(110) homoepitaxy. The inputs to the model were obtained from DFT [3,4]. Our model is in agreement with experimentally observed trends for this system. We used KMC to predict self-assembly under various growth conditions. To achieve precise placement of Al nanohuts, we simulated thermal-field-directed assembly [5]. Our results indicate that this technique can be used to create uniform arrays of nanostructures. [1] F. Buatier de Mongeot, W. Zhu, A. Molle, R. Buzio, C. Boragno, U. Valbusa, E. Wang, and Z. Zhang, Phys. Rev. Lett. 91, 016102 (2003). [2] W. Zhu, F. Buatier de Mongeot, U. Valbusa, E. G. Wang, and Z. Y. Zhang, Phys. Rev. Lett. 92, 106102 (2004). [3] Y. Tiwary and K. A. Fichthorn, submitted to Phys. Rev. B. [4] Y. Tiwary and K. A. Fichthorn, Phys. Rev. B 78, 205418 (2008). [5] C. Zhang and R. Kalyanaraman, Appl. Phys. Lett. 83, 4827 (2003).

  7. Motion of charged particle in Reissner-Nordström spacetime: a Jacobi-metric approach

    NASA Astrophysics Data System (ADS)

    Das, Praloy; Sk, Ripon; Ghosh, Subir

    2017-11-01

    The present work discusses motion of neutral and charged particles in Reissner-Nordström spacetime. The constant energy paths are derived in a variational principle framework using the Jacobi metric which is parameterized by conserved particle energy. Of particular interest is the case of particle charge and Reissner-Nordström black hole charge being of same sign, since this leads to a clash of opposing forces—gravitational (attractive) and Coulomb (repulsive). Our paper aims to complement the recent work of Pugliese et al. (Eur Phys J C 77:206. arXiv:1304.2940, 2017; Phys Rev D 88:024042. arXiv:1303.6250, 2013). The energy dependent Gaussian curvature (induced by the Jacobi metric) plays an important role in classifying the trajectories.

  8. Comment on ``The application of the thermodynamic perturbation theory to study the hydrophobic hydration'' [J. Chem. Phys. 139, 024101 (2013)

    NASA Astrophysics Data System (ADS)

    Graziano, Giuseppe

    2013-09-01

    It is shown that the behaviour of the hydration thermodynamic functions obtained in the 3D Mercedes-Benz model of water by Mohoric et al. [J. Chem. Phys. 139, 024101 (2013)] is not qualitatively correct with respect to experimental data for a solute whose diameter is 1.5-fold larger than that of a water molecule. It is also pointed out that the failure is due to the fact that the used 3D Mercedes-Benz model of water [A. Bizjak, T. Urbic, V. Vlachy, and K. A. Dill, J. Chem. Phys. 131, 194504 (2009)] does not reproduce in a quantitatively correct manner the peculiar temperature dependence of water density.

  9. Traces of Lorentz symmetry breaking in a hydrogen atom at ground state

    NASA Astrophysics Data System (ADS)

    Borges, L. H. C.; Barone, F. A.

    2016-02-01

    Some traces of a specific Lorentz symmetry breaking scenario in the ground state of the hydrogen atom are investigated. We use standard Rayleigh-Schrödinger perturbation theory in order to obtain the corrections to the ground state energy and the wave function. It is shown that an induced four-pole moment arises, due to the Lorentz symmetry breaking. The model considered is the one studied in Borges et al. (Eur Phys J C 74:2937, 2014), where the Lorentz symmetry is broken in the electromagnetic sector.

  10. Establishment of the Ph. Eur. Hepatitis A virus RNA for NAT testing BRP batch 1.

    PubMed

    Chudy, M; Nübling, C M; Blümel, J; Daas, A; Costanzo, A

    2017-01-01

    Detection of viral contamination in plasma donations is critical to prevent transmission of infectious diseases. The European Pharmacopoeia (Ph. Eur.) monograph 1646 'Human plasma (pooled and treated for virus inactivation)', requires that plasma pools used for the manufacture of this product be tested, among others, for the presence of hepatitis A virus RNA by nucleic acid testing (NAT) using a positive control containing 100 International Units (IU) of hepatitis A virus (HAV) RNA per mL. To this end, the European Directorate for the Quality of Medicines & HealthCare (EDQM, Council of Europe) organised an international collaborative study under the aegis of the Biological Standardisation Programme, for the establishment of the 1 st Biological Reference Preparation (BRP) for HAV RNA for NAT testing. A freeze-dried candidate material was thus prepared and calibrated against the WHO 2 nd International Standard for HAV for NAT (00/562) in a study in which thirteen European and North American laboratories including Official Medicines Control Laboratories (OMCLs), manufacturers of plasma-derived products, producers of in vitro diagnostic kits and a blood transfusion centre participated. Based on the outcome of the study, an HAV RNA content of 40 000 IU/vial (corresponding approximately to 4.6 log 10 IU/vial) was assigned to the BRP, which was adopted by the Ph. Eur. Commission in March 2016 as Ph. Eur. hepatitis A virus RNA for NAT testing BRP batch 1.

  11. Comment on “Maxwell's equations and electromagnetic Lagrangian density in fractional form” [J. Math. Phys. 53, 033505 (2012)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rabei, Eqab M.; Al-Jamel, A.; Widyan, H.

    In a recent paper, Jaradat et al. [J. Math. Phys. 53, 033505 (2012)] have presented the fractional form of the electromagnetic Lagrangian density within the Riemann-Liouville fractional derivative. They claimed that the Agrawal procedure [O. P. Agrawal, J. Math. Anal. Appl. 272, 368 (2002)] is used to obtain Maxwell's equations in the fractional form, and the Hamilton's equations of motion together with the conserved quantities obtained from fractional Noether's theorem are reported. In this comment, we draw the attention that there are some serious steps of the procedure used in their work are not applicable even though their final resultsmore » are correct. Their work should have been done based on a formulation as reported by Baleanu and Muslih [Phys. Scr. 72, 119 (2005)].« less

  12. Comment on “Frequency-domain stimulated and spontaneous light emission signals at molecular junctions” [J. Chem. Phys. 141, 074107 (2014)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Galperin, Michael; Ratner, Mark A.; Nitzan, Abraham

    2015-04-07

    We discuss the derivation of the optical response in molecular junctions presented by U. Harbola et al. [J. Chem. Phys. 141, 074107 (2014)], which questions some terms in the theory of Raman scattering in molecular junctions developed in our earlier publications. We show that the terms considered in our theory represent the correct contribution to calculated Raman scattering and are in fact identical to those considered by Harbola et al. We also indicate drawbacks of the presented approach in treating the quantum transport part of the problem.

  13. DPEMC: A Monte Carlo for double diffraction

    NASA Astrophysics Data System (ADS)

    Boonekamp, M.; Kúcs, T.

    2005-05-01

    We extend the POMWIG Monte Carlo generator developed by B. Cox and J. Forshaw, to include new models of central production through inclusive and exclusive double Pomeron exchange in proton-proton collisions. Double photon exchange processes are described as well, both in proton-proton and heavy-ion collisions. In all contexts, various models have been implemented, allowing for comparisons and uncertainty evaluation and enabling detailed experimental simulations. Program summaryTitle of the program:DPEMC, version 2.4 Catalogue identifier: ADVF Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADVF Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computer: any computer with the FORTRAN 77 compiler under the UNIX or Linux operating systems Operating system: UNIX; Linux Programming language used: FORTRAN 77 High speed storage required:<25 MB No. of lines in distributed program, including test data, etc.: 71 399 No. of bytes in distributed program, including test data, etc.: 639 950 Distribution format: tar.gz Nature of the physical problem: Proton diffraction at hadron colliders can manifest itself in many forms, and a variety of models exist that attempt to describe it [A. Bialas, P.V. Landshoff, Phys. Lett. B 256 (1991) 540; A. Bialas, W. Szeremeta, Phys. Lett. B 296 (1992) 191; A. Bialas, R.A. Janik, Z. Phys. C 62 (1994) 487; M. Boonekamp, R. Peschanski, C. Royon, Phys. Rev. Lett. 87 (2001) 251806; Nucl. Phys. B 669 (2003) 277; R. Enberg, G. Ingelman, A. Kissavos, N. Timneanu, Phys. Rev. Lett. 89 (2002) 081801; R. Enberg, G. Ingelman, L. Motyka, Phys. Lett. B 524 (2002) 273; R. Enberg, G. Ingelman, N. Timneanu, Phys. Rev. D 67 (2003) 011301; B. Cox, J. Forshaw, Comput. Phys. Comm. 144 (2002) 104; B. Cox, J. Forshaw, B. Heinemann, Phys. Lett. B 540 (2002) 26; V. Khoze, A. Martin, M. Ryskin, Phys. Lett. B 401 (1997) 330; Eur. Phys. J. C 14 (2000) 525; Eur. Phys. J. C 19 (2001) 477; Erratum, Eur. Phys. J. C 20 (2001) 599; Eur

  14. Comment on ``Scalings for radiation from plasma bubbles'' [Phys. Plasmas 17, 056708 (2010)

    NASA Astrophysics Data System (ADS)

    Corde, S.; Stordeur, A.; Malka, V.

    2011-03-01

    Thomas has recently derived scaling laws for x-ray radiation from electrons accelerated in plasma bubbles, as well as a threshold for the self-injection of background electrons into the bubble [A. G. R. Thomas, Phys. Plasmas 17, 056708 (2010)]. To obtain this threshold, the equations of motion for a test electron are studied within the frame of the bubble model, where the bubble is described by prescribed electromagnetic fields and has a perfectly spherical shape. The author affirms that any elliptical trajectory of the form x'2/γp2+y'2=R2 is solution of the equations of motion (in the bubble frame), within the approximation py'2/px'2≪1. In addition, he highlights that his result is different from the work of Kostyukov et al. [Phys. Rev. Lett. 103, 175003 (2009)], and explains the error committed by Kostyukov-Nerush-Pukhov-Seredov (KNPS). In this comment, we show that numerically integrated trajectories, based on the same equations than the analytical work of Thomas, lead to a completely different result for the self-injection threshold, the result published by KNPS [Phys. Rev. Lett. 103, 175003 (2009)]. We explain why the analytical analysis of Thomas fails and we provide a discussion based on numerical simulations which show exactly where the difference arises. We also show that the arguments of Thomas concerning the error of KNPS do not hold, and that their analysis is mathematically correct. Finally, we emphasize that if the KNPS threshold is found not to be verified in PIC (Particle In Cell) simulations or experiments, it is due to a deficiency of the model itself, and not to an error in the mathematical derivation.

  15. Comment on “Propagation of surface waves on a semi-bounded quantum magnetized collisional plasma” [Phys. Plasmas 20, 122106 (2013)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moradi, Afshin, E-mail: a.moradi@kut.ac.ir

    2016-04-15

    In a recent article [Niknam et al., Phys. Plasmas 20, 122106 (2013)], Niknam et al. investigated the propagation of TM surface waves on a semi-bounded quantum magnetized collisional plasma in the Faraday configuration (in this case, the magnetic field is parallel to the both of the plasma surface and direction of propagation). Here, we present a fresh look at the problem and show that TM surface waves cannot propagate on surface of the present system. We find in the Faraday configuration the surface waves acquire both TM and TE components due to the cyclotron motion of electrons. Therefore, the mainmore » result of the work by Niknam et al. is incorrect.« less

  16. Reply to the EFSA (2016) on the relevance of recent publications (Hofmann et al. 2014, 2016) on environmental risk assessment and management of Bt-maize events (MON810, Bt11 and 1507).

    PubMed

    Kruse-Plass, Maren; Hofmann, Frieder; Kuhn, Ulrike; Otto, Mathias; Schlechtriemen, Ulrich; Schröder, Boris; Vögel, Rudolf; Wosniok, Werner

    2017-01-01

    In this commentary, we respond to a report of the EFSA GMO Panel (EFSA EFSA Supp Publ, 1) that criticises the outcomes of two studies published in this journal (Hofmann et al. Environ Sci Eur 26: 24, 2; Environ Sci Eur 28: 14, 3). Both publications relate to the environmental risk assessment and management of Bt-maize, including maize events MON810, Bt11 and maize 1507. The results of Hofmann et al. (Environ Sci Eur 26: 24, 2), using standardised pollen mass filter deposition measurements, indicated that the EFSA Panel model had underestimated pollen deposition and, hence, exposure of non-target organisms to Bt-maize pollen. The results implied a need for safety buffer distances in the kilometre range for protected nature reserve areas instead of the 20-30 m range recommended by the EFSA Panel. As a result, the EFSA Panel revised their model (EFSA EFSA J 13: 4127, 4), adopting the slope of the empirical data from Hofmann et al. The intercept, however, was substantially reduced to less than 1% at one point by introducing further assumptions based on the estimates of mainly panel members, citing possible 'uncertainty'. Hofmann et al. (Environ Sci Eur 28: 14, 3) published extensive empirical data regarding pollen deposition on leaves. These results were part of a larger 3-year study involving detailed measurements of pollen release, dispersal and deposition over the maize flowering period. The data collected in situ confirmed the previous predictions of Hofmann et al. (Environ Sci Eur 26: 24, 2). Mean levels and observed variability of pollen deposition on maize and four lepidopteran host plants exceeded the assumptions and disagreed with the conclusions of the EFSA Panel. The EFSA Panel reacted in a report (EFSA EFSA Supp Publ, 1) criticising the methods and outcomes of the two published studies of Hofmann et al. while reaffirming their original recommendations. We respond here point-by-point, showing that the critique is not justified. Based on our results on

  17. 78 FR 48765 - Bureau of European and Eurasian Affairs (EUR) Request for Proposals for the Fundraising...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-09

    ... DEPARTMENT OF STATE [Public Notice 8397] Bureau of European and Eurasian Affairs (EUR) Request for Proposals for the Fundraising, Construction, Development, Organization, Management, Disassembly and Removal of a USA Pavilion/Exhibition at Universal Expo Milan Italy 2015, Hereafter Referred to as Milan Expo...

  18. Comment on "Analysis of single-layer metamaterial absorber with reflection theory" [J. Appl. Phys. 117, 154906 (2015)

    NASA Astrophysics Data System (ADS)

    Tung, Nguyen Thanh

    2016-03-01

    In a recent paper, Xiong et al. [J. Appl. Phys. 117, 154906 (2015)] presented the simulated results of a Jerusalem-cross structure in an attempt to elaborate their proposed reflection theory for metamaterial absorbers. Noting that even at non-resonant frequencies the real part of the permeability shows an over-high average value and its imaginary part drops abruptly from positivity to negativity, we argue that their simulated results are unphysical, resulting from an incomplete understanding of the retrieval procedure.

  19. Backward-forward reaction asymmetry of neutron elastic scattering on deuterium

    NASA Astrophysics Data System (ADS)

    Pirovano, E.; Beyer, R.; Junghans, A. R.; Nankov, N.; Nolte, R.; Nyman, M.; Plompen, A. J. M.

    2017-02-01

    A new measurement of the angular distribution of neutron elastic scattering on deuterium was carried out at the neutron time-of-flight facility nELBE. The backward-forward asymmetry of the reaction was investigated via the direct detection of neutrons scattered at the laboratory angle of 15∘ and 165∘ from a polyethylene sample enriched with deuterium. In order to extend the measurement to neutron energies below 1 MeV, 6Li glass scintillators were employed. The data were corrected for the background and the multiple scattering in the target, the events due to scattering on deuterium were separated from those due to carbon, and the ratio of the differential cross section at 15∘ and 165∘ was determined. The results, covering the energy range from 200 keV to 2 MeV, were found to be in agreement with the theoretical predictions calculated by Canton et al. [Eur. Phys. J. A 14, 225 (2002)], 10.1140/epja/i2001-10122-3 and by Golak et al. [Eur. Phys. J. A 50, 177 (2014)], 10.1140/epja/i2014-14177-7. The comparison with the evaluated nuclear data libraries indicated CENDL-3.1, JEFF-3.2, and JENDL-4.0 as the evaluations that best describe the asymmetry of n -d scattering. ENDF/B-VII.1 is compatible with the data for energies below 700 keV, but above the backward to forward ratio is higher than measured. ROSFOND-2010 and BROND-2.2 resulted to have little compatibility with the data.

  20. Description of proton radioactivity using the Coulomb and proximity potential model for deformed nuclei

    NASA Astrophysics Data System (ADS)

    Santhosh, K. P.; Sukumaran, Indu

    2017-09-01

    Half-life predictions have been performed for the proton emitters with Z >50 in the ground state and isomeric state using the Coulomb and proximity potential model for deformed nuclei (CPPMDN). The agreement of the calculated values with the experimental data made it possible to predict some proton emissions that are not verified experimentally yet. For a comparison, the calculations also are performed using other theoretical models, such as the Gamow-like model of Zdeb et al. [Eur. Phys. J. A 52, 323 (2016), 10.1140/epja/i2016-16323-7], the semiempirical relation of Hatsukawa et al. [Phys. Rev. C 42, 674 (1990), 10.1103/PhysRevC.42.674], and the CPPM of Santhosh et al. [Pramana 58, 611 (2002)], 10.1007/s12043-002-0019-2. The Geiger-Nuttall law, originally observed for α decay, studied for proton radioactivity is found to work well provided it is plotted for the isotopes of a given proton emitter nuclide with the same ℓ value. The universal curve is found to be valid for proton radioactivity also as we obtained a single straight line for all proton emissions irrespective of the parents. Through the analysis of the experimentally measured half-lives of 44 proton emitters, the study revealed that the present systematic study lends support to a unified description for studying α decay, cluster radioactivity, and proton radioactivity.

  1. The impact of vaccine success and awareness on epidemic dynamics

    NASA Astrophysics Data System (ADS)

    Juang, Jonq; Liang, Yu-Hao

    2016-11-01

    The role of vaccine success is introduced into an epidemic spreading model consisting of three states: susceptible, infectious, and vaccinated. Moreover, the effect of three types, namely, contact, local, and global, of infection awareness and immunization awareness is also taken into consideration. The model generalizes those considered in Pastor-Satorras and Vespignani [Phys. Rev. E 63, 066117 (2001)], Pastor-Satorras and Vespignani [Phys. Rev. E 65, 036104 (2002)], Moreno et al. [Eur. Phys. J. B 26, 521-529 (2002)], Wu et al. [Chaos 22, 013101 (2012)], and Wu et al. [Chaos 24, 023108 (2014)]. Our main results contain the following. First, the epidemic threshold is explicitly obtained. In particular, we show that, for any initial conditions, the epidemic eventually dies out regardless of what other factors are whenever some type of immunization awareness is considered, and vaccination has a perfect success. Moreover, the threshold is independent of the global type of awareness. Second, we compare the effect of contact and local types of awareness on the epidemic thresholds between heterogeneous networks and homogeneous networks. Specifically, we find that the epidemic threshold for the homogeneous network can be lower than that of the heterogeneous network in an intermediate regime for intensity of contact infection awareness while it is higher otherwise. In summary, our results highlight the important and crucial roles of both vaccine success and contact infection awareness on epidemic dynamics.

  2. Revisiting Deng et al.'s Multiparty Quantum Secret Sharing Protocol

    NASA Astrophysics Data System (ADS)

    Hwang, Tzonelih; Hwang, Cheng-Chieh; Yang, Chun-Wei; Li, Chuan-Ming

    2011-09-01

    The multiparty quantum secret sharing protocol [Deng et al. in Chin. Phys. Lett. 23: 1084-1087, 2006] is revisited in this study. It is found that the performance of Deng et al.'s protocol can be much improved by using the techniques of block-transmission and decoy single photons. As a result, the qubit efficiency is improved 2.4 times and only one classical communication, a public discussion, and two quantum communications between each agent and the secret holder are needed rather than n classical communications, n public discussions, and 3n/2 quantum communications required in the original scheme.

  3. B-decay anomalies in Pati-Salam SU(4)

    NASA Astrophysics Data System (ADS)

    Barbieri, Riccardo; Tesi, Andrea

    2018-03-01

    Attempts to incorporate in a coherent picture the B-decay anomalies presumably observed in b→ c and b→ s semi-leptonic decays have to face the absence of signals in other related experiments, both at low and at high energies. By extending and making more precise the content of Barbieri et al. (Eur Phys J C 77(1):8, 2017), we describe one such attempt based on the Pati-Salam SU(4) group, that unifies colour and the B- L charge, in the context of a new strongly interacting sector, equally responsible for producing a pseudo-Goldstone Higgs boson.

  4. GAMBIT: the global and modular beyond-the-standard-model inference tool. Addendum for GAMBIT 1.1: Mathematica backends, SUSYHD interface and updated likelihoods

    NASA Astrophysics Data System (ADS)

    Athron, Peter; Balazs, Csaba; Bringmann, Torsten; Buckley, Andy; Chrząszcz, Marcin; Conrad, Jan; Cornell, Jonathan M.; Dal, Lars A.; Dickinson, Hugh; Edsjö, Joakim; Farmer, Ben; Gonzalo, Tomás E.; Jackson, Paul; Krislock, Abram; Kvellestad, Anders; Lundberg, Johan; McKay, James; Mahmoudi, Farvah; Martinez, Gregory D.; Putze, Antje; Raklev, Are; Ripken, Joachim; Rogan, Christopher; Saavedra, Aldo; Savage, Christopher; Scott, Pat; Seo, Seon-Hee; Serra, Nicola; Weniger, Christoph; White, Martin; Wild, Sebastian

    2018-02-01

    In Ref. (GAMBIT Collaboration: Athron et. al., Eur. Phys. J. C. arXiv:1705.07908, 2017) we introduced the global-fitting framework GAMBIT. In this addendum, we describe a new minor version increment of this package. GAMBIT 1.1 includes full support for Mathematica backends, which we describe in some detail here. As an example, we backend SUSYHD (Vega and Villadoro, JHEP 07:159, 2015), which calculates the mass of the Higgs boson in the MSSM from effective field theory. We also describe updated likelihoods in PrecisionBit and DarkBit, and updated decay data included in DecayBit.

  5. The Hurst exponent in energy futures prices

    NASA Astrophysics Data System (ADS)

    Serletis, Apostolos; Rosenberg, Aryeh Adam

    2007-07-01

    This paper extends the work in Elder and Serletis [Long memory in energy futures prices, Rev. Financial Econ., forthcoming, 2007] and Serletis et al. [Detrended fluctuation analysis of the US stock market, Int. J. Bifurcation Chaos, forthcoming, 2007] by re-examining the empirical evidence for random walk type behavior in energy futures prices. In doing so, it uses daily data on energy futures traded on the New York Mercantile Exchange, over the period from July 2, 1990 to November 1, 2006, and a statistical physics approach-the ‘detrending moving average’ technique-providing a reliable framework for testing the information efficiency in financial markets as shown by Alessio et al. [Second-order moving average and scaling of stochastic time series, Eur. Phys. J. B 27 (2002) 197-200] and Carbone et al. [Time-dependent hurst exponent in financial time series. Physica A 344 (2004) 267-271; Analysis of clusters formed by the moving average of a long-range correlated time series. Phys. Rev. E 69 (2004) 026105]. The results show that energy futures returns display long memory and that the particular form of long memory is anti-persistence.

  6. Role and goals of the EUR-OCEANS Consortium - Bringing marine scientists priorities and strategies to the European research planning agenda.

    NASA Astrophysics Data System (ADS)

    Cury, Philippe; Baisnée, Pierre-François

    2010-05-01

    The EUR-OCEANS Consortium is the follow-up structure of the homonym European Network of Excellence (NoE; 2005-2008, FP6 contract number 511106). It is a scientific network, benefiting from and relying upon the institutional commitment of the 27 research performing organisations forming its core (paying) membership. It aims at the long-term harmonization of European research efforts related to ocean ecosystems undergoing anthropogenic and natural forcing. More specifically, its objectives are to facilitate and promote: (1) top-level scientific research on the impacts of anthropogenic and natural forcing on ocean ecosystems, fostering collaborations across the European Research Area; (2) the optimal use of any shared technical infrastructures and scientific facilities; and (3) activities to spread excellence, such as the training of scientific personnel and students, or knowledge dissemination towards the general public and socio-economic users. A particular focus is put during the first scientific coordination mandate on the building of scenarios for marine ecosystems under anthropogenic and natural forcing in the XXI Century, and on the improvement of the science-policy interface. Through calls for projects and networking activities, the Consortium seeks to favour the emergence of coordinated projects on key hot topics on one hand, and the crystallisation of scientific priorities and strategies that could serve as input to ERA-NETs, ESFRI, Joint Programming Initiatives and European Research Planning actors in general. While being an active standalone structure, the Consortium is also engaged in the Euromarine FP7 project (submitted) aiming at the definition of a common coordinating or integrating structure for the three follow-up entities of FP6 marine science NoEs (Marine Genomics Europe, MarBEF, EUR-OCEANS). The 2009-2011 strategy and activity plan of EUR-OCEANS will be presented and the involvement of EUR-OCEANS members in other key projects or programmes will

  7. Exploring Physics with Computer Animation and PhysGL

    NASA Astrophysics Data System (ADS)

    Bensky, T. J.

    2016-10-01

    This book shows how the web-based PhysGL programming environment (http://physgl.org) can be used to teach and learn elementary mechanics (physics) using simple coding exercises. The book's theme is that the lessons encountered in such a course can be used to generate physics-based animations, providing students with compelling and self-made visuals to aid their learning. Topics presented are parallel to those found in a traditional physics text, making for straightforward integration into a typical lecture-based physics course. Users will appreciate the ease at which compelling OpenGL-based graphics and animations can be produced using PhysGL, as well as its clean, simple language constructs. The author argues that coding should be a standard part of lower-division STEM courses, and provides many anecdotal experiences and observations, that include observed benefits of the coding work.

  8. Spectral geometry of {kappa}-Minkowski space

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    D'Andrea, Francesco

    After recalling Snyder's idea [Phys. Rev. 71, 38 (1947)] of using vector fields over a smooth manifold as 'coordinates on a noncommutative space', we discuss a two-dimensional toy-model whose 'dual' noncommutative coordinates form a Lie algebra: this is the well-known {kappa}-Minkowski space [Phys. Lett. B 334, 348 (1994)]. We show how to improve Snyder's idea using the tools of quantum groups and noncommutative geometry. We find a natural representation of the coordinate algebra of {kappa}-Minkowski as linear operators on an Hilbert space (a major problem in the construction of a physical theory), study its 'spectral properties', and discuss how tomore » obtain a Dirac operator for this space. We describe two Dirac operators. The first is associated with a spectral triple. We prove that the cyclic integral of Dimitrijevic et al. [Eur. Phys. J. C 31, 129 (2003)] can be obtained as Dixmier trace associated to this triple. The second Dirac operator is equivariant for the action of the quantum Euclidean group, but it has unbounded commutators with the algebra.« less

  9. Bierman {ital et al.}Reply:

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bierman, J.D.; Chan, P.; Liang, J.F.

    1997-05-01

    reply to the Comment by C.H.Dasso et al., Phys. Rev. Lett. 78,XXX(1997). A Reply to the Comment by C.H. Dasso and J. Fern{acute a}ndez-Niello. {copyright} {ital 1997} {ital The American Physical Society}

  10. GERDA: Results and perspectives

    NASA Astrophysics Data System (ADS)

    Cattadori, Carla Maria; GERDA Collaboration

    2015-08-01

    From November 2011 to May 2013, GERDA searched for 0 νββ and 2 νββ of 76Ge, operating bare in a liquid argon bath Ge detectors enriched up to ˜ 87% in 76Ge (enrGe), for a total mass of ˜ 18 kg of enrGe. A total exposure of 21.6 kgṡy, of enrGe was collected, and the existing claim [H. V. Klapdor-Kleingrothaus et al., Phys. Lett. B 586 (2004) 198] of 0 νββ evidence was scrutinized. GERDA didn't observe any peak at Qββ or in its immediate surroundings; the limit of T1/20ν > 2.1 ṡ1025 yr (90 % C.L.) is derived [GERDA collaboration: M. Agostini et al., Phys. Rev. Lett. 111, (2013) 122503]. When combining the GERDA limit with those of past HdM [HdM collaboration: H. V. Klapdor-Kleingrothaus et al., Eur. Phys. J. A12 (2001) 147] and Igex [Igex Collaboration: C. E. Aalseth et al., Phys. Rev. D 65 (2002) 092007] experiments, the lower limit of 3.0 ṡ1025 yr (90 % C.L.) on T1/20ν is achieved. The background index (BI) at Qββ (˜ 2039 keV) is ˜ 2.0 ṡ10-2 cts / (keV ṡkg ṡyr) and ˜ 1.0 ṡ10-2 cts / (keV ṡkg ṡyr), prior and after the pulse shape cuts respectively. Thanks to the low background the 2 νββ dominates the energy spectrum below 1800 keV: the Tν1/2 2 = (1.84-0.10+0.14) ṡ1021y was derived on a first data set corresponding to 5.1 kgṡyr exposure [GERDA collaboration: M. Agostini et al., J. Phys. G 40 (2013), 035110]. The ongoing experimental program, to double the exposed mass by adding new enrGe detectors with improved pulse shape discrimination features, and to implement the liquid argon scintillation light readout is outlined.

  11. EurEAs_Gplex--A new SNaPshot assay for continental population discrimination and gender identification.

    PubMed

    Daca-Roszak, P; Pfeifer, A; Żebracka-Gala, J; Jarząb, B; Witt, M; Ziętkiewicz, E

    2016-01-01

    Assays that allow analysis of the biogeographic origin of biological samples in a standard forensic laboratory have to target a small number of highly differentiating markers. Such markers should be easy to multiplex and the assay must perform well in the degraded and scarce biological material. SNPs localized in the genome regions, which in the past were subjected to differential selective pressure in various populations, are the most widely used markers in the studies of biogeographic affiliation. SNPs reflecting biogeographic differences not related to any phenotypic traits are not sufficiently explored. The goal of our study was to identify a small set of SNPs not related to any known pigmentation/phenotype-specific genes, which would allow efficient discrimination between populations of Europe and East Asia. The selection of SNPs was based on the comparative analysis of representative European and Chinese/Japanese samples (B-lymphocyte cell lines), genotyped using the Infinium HumanOmniExpressExome microarray (Illumina). The classifier, consisting of 24 unlinked SNPs (24-SNP classifier), was selected. The performance of a 14-SNP subset of this classifier (14-SNP subclassifier) was tested using genotype data from several populations. The 14-SNP subclassifier differentiated East Asians, Europeans and Africans with ∼100% accuracy; Palestinians, representative of the Middle East, clustered with Europeans, while Amerindians and Pakistani were placed between East Asian and European populations. Based on these results, we have developed a SNaPshot assay (EurEAs_Gplex) for genotyping SNPs from the 14-SNP subclassifier, combined with an additional marker for gender identification. Forensic utility of the EurEAs_Gplex was verified using degraded and low quantity DNA samples. The performance of the EurEAs_Gplex was satisfactory when using degraded DNA; tests using low quantity DNA samples revealed a previously not described source of genotyping errors, potentially

  12. On the Boltzmann-Grad Limit for Smooth Hard-Sphere Systems

    NASA Astrophysics Data System (ADS)

    Tessarotto, Massimo; Cremaschini, Claudio; Mond, Michael; Asci, Claudio; Soranzo, Alessandro; Tironi, Gino

    2018-03-01

    The problem is posed of the prescription of the so-called Boltzmann-Grad limit operator (L_{BG}) for the N-body system of smooth hard-spheres which undergo unary, binary as well as multiple elastic instantaneous collisions. It is proved, that, despite the non-commutative property of the operator L_{BG}, the Boltzmann equation can nevertheless be uniquely determined. In particular, consistent with the claim of Uffink and Valente (Found Phys 45:404, 2015) that there is "no time-asymmetric ingredient" in its derivation, the Boltzmann equation is shown to be time-reversal symmetric. The proof is couched on the "ab initio" axiomatic approach to the classical statistical mechanics recently developed (Tessarotto et al. in Eur Phys J Plus 128:32, 2013). Implications relevant for the physical interpretation of the Boltzmann H-theorem and the phenomenon of decay to kinetic equilibrium are pointed out.

  13. Isospectral discrete and quantum graphs with the same flip counts and nodal counts

    NASA Astrophysics Data System (ADS)

    Juul, Jonas S.; Joyner, Christopher H.

    2018-06-01

    The existence of non-isomorphic graphs which share the same Laplace spectrum (to be referred to as isospectral graphs) leads naturally to the following question: what additional information is required in order to resolve isospectral graphs? It was suggested by Band, Shapira and Smilansky that this might be achieved by either counting the number of nodal domains or the number of times the eigenfunctions change sign (the so-called flip count) (Band et al 2006 J. Phys. A: Math. Gen. 39 13999–4014 Band and Smilansky 2007 Eur. Phys. J. Spec. Top. 145 171–9). Recent examples of (discrete) isospectral graphs with the same flip count and nodal count have been constructed by Ammann by utilising Godsil–McKay switching (Ammann private communication). Here, we provide a simple alternative mechanism that produces systematic examples of both discrete and quantum isospectral graphs with the same flip and nodal counts.

  14. Many-Body Effect in Spin Dephasing in n-Type GaAs Quantum Wells

    NASA Astrophysics Data System (ADS)

    Weng, Ming-Qi; Wu, Ming-Wei

    2005-03-01

    By constructing and numerically solving the kinetic Bloch equations we perform a many-body study of the spin dephasing due to the D'yakonov-Perel' effect in n-type GaAs (100) quantum wells for high temperatures. In our study, we include the spin-conserving scattering such as the electron-phonon, the electron-nonmagnetic impurity as well as the electron-electron Coulomb scattering into consideration. The dephasing obtained from our theory contains both the single-particle and the many-body contributions with the latter originating from the inhomogeneous broadening introduced by the DP term [J. Supercond.: Incorp. Novel Magn. 14 (2001) 245 Eur. Phys. J. B 18 (2000) 373]. Our result agrees very well with the experimental data [Phys. Rev. B 62 (2000) 13034] of Malinowski et al. We further show that in the case we study, the spin dephasing is dominated by the many-body effect.

  15. Stripe-teeth metamaterial Al- and Nb-based rectennas (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Osgood, Richard M.; Giardini, Stephen A.; Carlson, Joel B.; Joghee, Prabhuram; O'Hayre, Ryan P.; Diest, Kenneth; Rothschild, Mordechai

    2015-09-01

    Unlike a semiconductor, where the absorption is limited by the band gap, a "microrectenna array" could theoretically very efficiently rectify any desired portion of the infrared frequency spectrum (25 - 400 THz). We investigated vertical metal-insulator-metal (MIM) diodes that rectify vertical high-frequency fields produced by a metamaterial planar stripe-teeth Al or Au array (above the diodes), similar to stripe arrays that have demonstrated near-perfect absorption in the infrared due to critical coupling [1]. Using our design rules that maximize asymmetry (and therefore the component of the electric field pointed into the substrate, analogous to Second Harmonic Generation), we designed, fabricated, and analyzed these metamaterial-based microrectenna arrays. NbOx and Al2O3 were produced by anodization and ALD, respectively. Smaller visible-light Pt-NbOx-Nb rectennas have produced output power when illuminated by visible (514 nm) light [2]. The resonances of these new Au/NbOx/Nb and Al/Al2O3/Al microrectenna arrays, with larger dimensions and more complex nanostructures than in Ref. 1, were characterized by microscopic FTIR microscopy and agreed well with FDTD models, once the experimental refractive index values were entered into the model. Current-voltage measurements were carried out, showed that the Al/Al2O3/Al diodes have very large barrier heights and breakdown voltages, and were compared to our model of the MIM diode. We calculate expected THz-rectification using classical [3] and quantum [4] rectification models, and compare to measurements of direct current output, under infrared illumination. [1] C. Wu, et. al., Phys. Rev. B 84 (2011) 075102. [2] R. M. Osgood III, et. al., Proc. SPIE 8096, 809610 (2011). [3] A. Sanchez, et. al., J. Appl. Phys. 49 (1978) 5270. [4] J. R. Tucker and M. J. Feldman, Rev. of Mod. Phys. 57, (1985)1055.

  16. Comment on ‘Wind-influenced projectile motion’

    NASA Astrophysics Data System (ADS)

    Winther Andersen, Poul

    2015-11-01

    We comment on the article ‘Wind-influenced projectile motion’ by Bernardo et al (2015 Eur. J. Phys. 36 025016) where they examine the trajectory of a particle that is subjected to gravity and a linear air resistance plus the influence from the wind. They find by using the Lambert W function that the particle's trajectory for a special angle, the critical angle {θ }{{C}}, between the initial velocity and the horizontal is part of a straight line. In this comment we will show that this result can be proved without using the Lambert W function which is not that well known to beginning students of physics.

  17. Spectroscopy of the hydrogen 1 S -3 S transition with chirped laser pulses

    NASA Astrophysics Data System (ADS)

    Yost, D. C.; Matveev, A.; Grinin, A.; Peters, E.; Maisenbacher, L.; Beyer, A.; Pohl, R.; Kolachevsky, N.; Khabarova, K.; Hänsch, T. W.; Udem, Th.

    2016-04-01

    We identify a systematic present in two-photon direct frequency comb spectroscopy (DFCS) which is a result of chirped laser pulses and is a manifestation of the first-order Doppler effect. We carefully analyze this systematic and propose methods for its mitigation within the context of our measurement of the hydrogen 1 S -3 S transition. We also report on our determination of the absolute frequency of this transition, which is comparable to a previous measurement using continuous-wave spectroscopy [O. Arnoult et al., Eur. Phys. J. D 60, 243 (2010), 10.1140/epjd/e2010-00249-6], but was obtained with a different experimental method.

  18. Study of Spin Splitting in GaN/AlGaN Quantum Wells

    DTIC Science & Technology

    2009-05-11

    plasma-assisted molecular - beam epitaxy ”, Jap. J. Appl. Phys. 47, 891 (2008), we have grown M-plane GaN films with self-assembled C-plane GaN nanopillars...on a γ-LiAlO2 substrate by plasma-assisted molecular - beam epitaxy . The diameters of the basal plane of the nanopillars are about 200 to 900 nm and...Line defects of M-plane GaN grown on γ-LiAlO2 by plasma-assisted molecular beam epitaxy ”, Appl. Phys. Lett. 92 pp.202106 (2008), we studied the

  19. Comment on "Study of dielectric relaxations of anhydrous trehalose and maltose glasses" [J. Chem. Phys. 134, 014508 (2011)].

    PubMed

    Kaminski, K; Wlodarczyk, P; Paluch, M

    2011-10-28

    Very recently Kwon et al. [H.-J. Kwon, J.-A. Seo, H. K. Kim, and Y. H. Hwang, J. Chem. Phys. 134, 014508 (2011)] published an article on the study of dielectric relaxation in trehalose and maltose glasses. They carried out broadband dielectric measurements at very wide range of temperatures covering supercooled liquid as well as glassy state of both saccharides. It is worth to mention that authors have also applied a new method for obtaining anhydrous glasses of trehalose and maltose that enables avoiding their caramelization. Four relaxation processes were identified in dielectric spectra of both saccharides. The slower one was identified as structural relaxation process the next one, not observed by the others, was assigned as Johari-Goldstein (JG) β-relaxation, while the last two secondary modes were of the same nature as found by Kaminski et al. [K. Kaminski, E. Kaminska, P. Wlodarczyk, S. Pawlus, D. Kimla, A. Kasprzycka, M. Paluch, J. Ziolo, W. Szeja, and K. L. Ngai, J. Phys. Chem. B 112, 12816 (2008)]. In this comment we show that the authors mistakenly assigned the slowest relaxation process as structural mode of disaccharides. We have proven that this relaxation process is an effect of formation of thin layer of air or water between plate of capacitor and sample. The same effect can be observed if plates of capacitor are oxidized. Thus, we concluded that their slowest mode is connected to the dc conduction process while their β JG process is primary relaxation of trehalose and maltose.

  20. Reply to comment on ‘Poynting flux in the neighbourhood of a point charge in arbitrary motion and the radiative power losses’

    NASA Astrophysics Data System (ADS)

    Singal, Ashok K.

    2018-01-01

    Doubts have been expressed in a comment about the tenability of the formulation for radiative losses in our recent published work (Singal 2016 Eur. J. Phys. 37 045210). We provide our reply to the comment.

  1. Comment on ``Anisotropy studies of molecular-beam-epitaxy-grown Co(111) thin films by ferromagnetic resonance'' [J. Appl. Phys. 75, 6492 (1994)

    NASA Astrophysics Data System (ADS)

    Artman, J. O.

    1995-05-01

    The magnetic free energy expression E used to calculate ferromagnetic resonance frequencies by F. Schreiber et al., J. Appl. Phys. 75, 6492 (1994) is examined. The expression is correct for hexagonal site symmetry films but not for any type of cubic symmetry film. The correct expression, including both K1c and K2c anisotropy contributions, for E with H in the basal plane of a (111) film is given in the text.

  2. About the coordinate time for photons in Lifshitz space-times

    NASA Astrophysics Data System (ADS)

    Villanueva, J. R.; Vásquez, Yerko

    2013-10-01

    In this paper we studied the behavior of radial photons from the point of view of the coordinate time in (asymptotically) Lifshitz space-times, and we found a generalization to the result reported in previous works by Cruz et al. (Eur. Phys. J. C 73:7, 2013), Olivares et al. (Astrophys. Space Sci. 347:83-89, 2013), and Olivares et al. (arXiv:1306.5285). We demonstrate that all asymptotically Lifshitz space-times characterized by a lapse function f( r) which tends to one when r→∞, present the same behavior, in the sense that an external observer will see that photons arrive at spatial infinity in a finite coordinate time. Also, we show that radial photons in the proper system cannot determine the presence of the black hole in the region r +< r<∞, because the proper time as a result is independent of the lapse function f( r).

  3. NOTE: Calculating diffraction patterns

    NASA Astrophysics Data System (ADS)

    Rioux, Frank

    2003-05-01

    Following Marcella's approach to the double-slit experiment (Marcella T V 2002 Eur. J. Phys. 23 615-21), diffraction patterns for two-dimensional masks are calculated by Fourier transform of the Mask geometry into momentum space.

  4. e-Phys: a suite of intracellular neurophysiology programs integrating COM (component object model) technologies.

    PubMed

    Nguyen, Quoc-Thang; Miledi, Ricardo

    2003-09-30

    Current computer programs for intracellular recordings often lack advanced data management, are usually incompatible with other applications and are also difficult to adapt to new experiments. We have addressed these shortcomings in e-Phys, a suite of electrophysiology applications for intracellular recordings. The programs in e-Phys use Component Object Model (COM) technologies available in the Microsoft Windows operating system to provide enhanced data storage, increased interoperability between e-Phys and other COM-aware applications, and easy customization of data acquisition and analysis thanks to a script-based integrated programming environment. Data files are extensible, hierarchically organized and integrated in the Windows shell by using the Structured Storage technology. Data transfers to and from other programs are facilitated by implementing the ActiveX Automation standard and distributed COM (DCOM). ActiveX Scripting allows experimenters to write their own event-driven acquisition and analysis programs in the VBScript language from within e-Phys. Scripts can reuse components available from other programs on other machines to create distributed meta-applications. This paper describes the main features of e-Phys and how this package was used to determine the effect of the atypical antipsychotic drug clozapine on synaptic transmission at the neuromuscular junction.

  5. LETTERS AND COMMENTS: Note on the 'log formulae' for pendulum motion valid for any amplitude

    NASA Astrophysics Data System (ADS)

    Qing-Xin, Yuan; Pei, Ding

    2010-01-01

    In this note, we present an improved approximation to the solution of Lima (2008 Eur. J. Phys. 29 1091), which decreases the maximum relative error from 0.6% to 0.084% in evaluating the exact pendulum period.

  6. Pure AlN layers in metal-polar AlGaN/AlN/GaN and AlN/GaN heterostructures grown by low-temperature ammonia-based molecular beam epitaxy

    NASA Astrophysics Data System (ADS)

    Kaun, Stephen W.; Mazumder, Baishakhi; Fireman, Micha N.; Kyle, Erin C. H.; Mishra, Umesh K.; Speck, James S.

    2015-05-01

    When grown at a high temperature (820 °C) by ammonia-based molecular beam epitaxy (NH3-MBE), the AlN layers of metal-polar AlGaN/AlN/GaN heterostructures had a high GaN mole fraction (∼0.15), as identified by atom probe tomography in a previous study (Mazumder et al 2013 Appl. Phys. Lett. 102 111603). In the study presented here, growth at low temperature (<740 °C) by NH3-MBE yielded metal-polar AlN layers that were essentially pure at the alloy level. The improved purity of the AlN layers grown at low temperature was correlated to a dramatic increase in the sheet density of the two-dimensional electron gas (2DEG) at the AlN/GaN heterointerface. Through application of an In surfactant, metal-polar AlN(3.5 nm)/GaN and AlGaN/AlN(2.5 nm)/GaN heterostructures grown at low temperature yielded low 2DEG sheet resistances of 177 and 285 Ω/□, respectively.

  7. Motif-based success scores in coauthorship networks are highly sensitive to author name disambiguation

    NASA Astrophysics Data System (ADS)

    Klosik, David F.; Bornholdt, Stefan; Hütt, Marc-Thorsten

    2014-09-01

    Following the work of Krumov et al. [Eur. Phys. J. B 84, 535 (2011), 10.1140/epjb/e2011-10746-5] we revisit the question whether the usage of large citation datasets allows for the quantitative assessment of social (by means of coauthorship of publications) influence on the progression of science. Applying a more comprehensive and well-curated dataset containing the publications in the journals of the American Physical Society during the whole 20th century we find that the measure chosen in the original study, a score based on small induced subgraphs, has to be used with caution, since the obtained results are highly sensitive to the exact implementation of the author disambiguation task.

  8. Transverse enhancement model and MiniBooNE charge current quasi-elastic neutrino scattering data

    NASA Astrophysics Data System (ADS)

    Sobczyk, Jan T.

    2012-01-01

    Recently proposed Transverse Enhancement Model of nuclear effects in Charge Current Quasi-Elastic neutrino scattering (A. Bodek, H.S. Budd, M.E. Christy, Eur. Phys. J. C 71:1726, 2011) is confronted with the MiniBooNE high statistics experimental data.

  9. Sintering of (Ni,Mg)(Al,Fe)2O4 Materials and their Corrosion Process in Na3AlF6-AlF3-K3AlF6 Electrolyte

    NASA Astrophysics Data System (ADS)

    Xu, Yibiao; Li, Yawei; Yang, Jianhong; Sang, Shaobai; Wang, Qinghu

    2017-06-01

    The application of ledge-free sidewalls in the Hall-Héroult cells can potentially reduce the energy requirement of aluminum production by about 30 pct (Nightingale et al. in J Eur Ceram, 33:2761-2765, 2013). However, this approach poses great material challenges since such sidewalls are in direct contact with corrosive electrolyte. In the present paper, (Ni,Mg)(Al,Fe)2O4 materials were prepared using fused magnesia, reactive alumina, nickel oxide, and iron oxide powders as the starting materials. The sintering behaviors of specimens as well as their corrosion resistance to molten electrolyte have been investigated by means of X-ray diffraction and scanning electron microscope. The results show that after firing at temperature ranging from 1673 K (1400 °C) up to 1873 K (1600 °C), all the specimens prepared are composed of single-phase (Ni,Mg)(Al,Fe)2O4 composite spinel, the lattice parameter of which increases with increasing Fe3+ ion concentration. Increasing the iron oxide content enhances densification of the specimens, which is accompanied by the formation of homogeneously distributed smaller pores in the matrix. The corrosion tests show that corrosion layers consist of fluoride and Ni(Al,Fe)2O4 composite spinel grains are produced in specimens with Fe/Al mole ratio no more than 1, whereas dense Ni(Al,Fe)2O4 composite spinel layers are formed on the surface of the specimens with Fe/Al mole ratio more than 1. The dense Ni(Al,Fe)2O4 composite spinel layers formed improve the corrosion resistance of the specimens by inhibiting the infiltration of electrolyte and hindering the chemical reaction between the specimen and electrolyte.

  10. The Aharonov-Bohm effect and Tonomura et al. experiments: Rigorous results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ballesteros, Miguel; Weder, Ricardo

    The Aharonov-Bohm effect is a fundamental issue in physics. It describes the physically important electromagnetic quantities in quantum mechanics. Its experimental verification constitutes a test of the theory of quantum mechanics itself. The remarkable experiments of Tonomura et al. ['Observation of Aharonov-Bohm effect by electron holography', Phys. Rev. Lett 48, 1443 (1982) and 'Evidence for Aharonov-Bohm effect with magnetic field completely shielded from electron wave', Phys. Rev. Lett 56, 792 (1986)] are widely considered as the only experimental evidence of the physical existence of the Aharonov-Bohm effect. Here we give the first rigorous proof that the classical ansatz of Aharonovmore » and Bohm of 1959 ['Significance of electromagnetic potentials in the quantum theory', Phys. Rev. 115, 485 (1959)], that was tested by Tonomura et al., is a good approximation to the exact solution to the Schroedinger equation. This also proves that the electron, that is, represented by the exact solution, is not accelerated, in agreement with the recent experiment of Caprez et al. in 2007 ['Macroscopic test of the Aharonov-Bohm effect', Phys. Rev. Lett. 99, 210401 (2007)], that shows that the results of the Tonomura et al. experiments can not be explained by the action of a force. Under the assumption that the incoming free electron is a Gaussian wave packet, we estimate the exact solution to the Schroedinger equation for all times. We provide a rigorous, quantitative error bound for the difference in norm between the exact solution and the Aharonov-Bohm Ansatz. Our bound is uniform in time. We also prove that on the Gaussian asymptotic state the scattering operator is given by a constant phase shift, up to a quantitative error bound that we provide. Our results show that for intermediate size electron wave packets, smaller than the ones used in the Tonomura et al. experiments, quantum mechanics predicts the results observed by Tonomura et al. with an error bound smaller

  11. Multi-scale simulation of quantum dot formation in Al/Al (110) homoepitaxy

    NASA Astrophysics Data System (ADS)

    Tiwary, Yogesh; Fichthorn, Kristen

    2007-03-01

    In experimental studies of Al(110) homoepitaxy, it is observed that over a certain temperature window (330-500K), 3D huts, up to 50 nm high with well defined and smooth (111) and (100) facets, form and self-organize over the micron scale [1]. The factors leading to this kinetic self-organization are currently unclear. To understand how these structures form and evolve, we simulated multi-layer, homoepitaxial growth on Al(110) using ab initio kinetic Monte Carlo (KMC). At the high temperatures, where nano-huts form, the KMC simulations are slow. To tackle this problem, we use a technique developed by Devita & Sander [2], in which isolated adatoms make multiple moves in one step. We achieve high efficiency with this algorithm and we explore very high temperatures on large simulation lattices. We uncover a variety of interesting morphologies (Ripples, mounds, smooth surface, huts) that depend on the growth temperature. By varying the barriers for various rate processes, we discern the factors that determine hut sizes, aspect ratios, and self-organization. [1] F. Buatier de Mongeot, W. Zhu, A. Molle, R. Buzio, C. Boragno, U. Valbusa, E. Wang, and Z. Zhang, Phys. Rev. Lett. 91, 016102 (2003). [2] J.P. Devita & L.M. Sander, Phys. Rev. B 72, 205421 (2005).

  12. iNuc-PhysChem: A Sequence-Based Predictor for Identifying Nucleosomes via Physicochemical Properties

    PubMed Central

    Feng, Peng-Mian; Ding, Chen; Zuo, Yong-Chun; Chou, Kuo-Chen

    2012-01-01

    Nucleosome positioning has important roles in key cellular processes. Although intensive efforts have been made in this area, the rules defining nucleosome positioning is still elusive and debated. In this study, we carried out a systematic comparison among the profiles of twelve DNA physicochemical features between the nucleosomal and linker sequences in the Saccharomyces cerevisiae genome. We found that nucleosomal sequences have some position-specific physicochemical features, which can be used for in-depth studying nucleosomes. Meanwhile, a new predictor, called iNuc-PhysChem, was developed for identification of nucleosomal sequences by incorporating these physicochemical properties into a 1788-D (dimensional) feature vector, which was further reduced to a 884-D vector via the IFS (incremental feature selection) procedure to optimize the feature set. It was observed by a cross-validation test on a benchmark dataset that the overall success rate achieved by iNuc-PhysChem was over 96% in identifying nucleosomal or linker sequences. As a web-server, iNuc-PhysChem is freely accessible to the public at http://lin.uestc.edu.cn/server/iNuc-PhysChem. For the convenience of the vast majority of experimental scientists, a step-by-step guide is provided on how to use the web-server to get the desired results without the need to follow the complicated mathematics that were presented just for the integrity in developing the predictor. Meanwhile, for those who prefer to run predictions in their own computers, the predictor's code can be easily downloaded from the web-server. It is anticipated that iNuc-PhysChem may become a useful high throughput tool for both basic research and drug design. PMID:23144709

  13. Erratum: Hansen et al (2014).

    PubMed

    2015-04-01

    In the article by Hansen AW, Dahl-Petersen I, Helge JW, et al, "Validation of an Internet-Based Long Version of the International Physical Activity Questionnaire in Danish Adults Using Combined Accelerometry and Heart Rate Monitoring," in J Phys Act Health, 11(3), p. 654, the DOI was listed incorrectly (10.1123/jpah.2012-0040a). This error has been fixed. The publisher apologizes for the error.

  14. Combustion Synthesis Reaction Behavior of Cold-Rolled Ni/Al and Ti/Al Multilayers

    DTIC Science & Technology

    2011-04-01

    6   Figure 4 . Combustion synthesis process of the cold-rolled Ni/Al multilayer foils: (a) reaction front of the displacement of the reaction...Reactive Nanostructured Foil Used as a Heat Source for Joining Titanium . J. Appl. Phys. 2004, 96 ( 4 ), 2336–2342. 16. Wang, J.; Besnoin, E...2011 2. REPORT TYPE Final 3. DATES COVERED (From - To) January 2006–January 2008 4 . TITLE AND SUBTITLE Combustion Synthesis Reaction Behavior of

  15. Statistical Equilibria of Turbulence on Surfaces of Different Symmetry

    NASA Astrophysics Data System (ADS)

    Qi, Wanming; Marston, Brad

    2012-02-01

    We test the validity of statistical descriptions of freely decaying 2D turbulence by performing direct numerical simulations (DNS) of the Euler equation with hyperviscosity on a square torus and on a sphere. DNS shows, at long times, a dipolar coherent structure in the vorticity field on the torus but a quadrapole on the sphereootnotetextJ. Y-K. Cho and L. Polvani, Phys. Fluids 8, 1531 (1996).. A truncated Miller-Robert-Sommeria theoryootnotetextA. J. Majda and X. Wang, Nonlinear Dynamics and Statistical Theories for Basic Geophysical Flows (Cambridge University Press, 2006). can explain the difference. The theory conserves up to the second-order Casimir, while also respecting conservation laws that reflect the symmetry of the domain. We further show that it is equivalent to the phenomenological minimum-enstrophy principle by generalizing the work by Naso et al.ootnotetextA. Naso, P. H. Chavanis, and B. Dubrulle, Eur. Phys. J. B 77, 284 (2010). to the sphere. To explain finer structures of the coherent states seen in DNS, especially the phenomenon of confinement, we investigate the perturbative inclusion of the higher Casimir constraints.

  16. Formation of epitaxial Al 2O 3/NiAl(1 1 0) films: aluminium deposition

    NASA Astrophysics Data System (ADS)

    Lykhach, Y.; Moroz, V.; Yoshitake, M.

    2005-02-01

    Structure of epitaxial Al 2O 3 layers formed on NiAl(1 1 0) substrates has been studied by means of reflection high-energy electron diffraction (RHEED). The elucidated structure was compared to the model suggested for 0.5 nm-thick Al 2O 3 layers [K. Müller, H. Lindner, D.M. Zehner, G. Ownby, Verh. Dtsch. Phys. Ges. 25 (1990) 1130; R.M. Jaeger, H. Kuhlenbeck, H.J. Freund, Surf. Sci. 259 (1991) 235]. The stepwise growth of Al 2O 3 film, involving deposition and subsequent oxidation of aluminium onto epitaxial 0.5 nm-thick Al 2O 3 layers, has been investigated. Aluminium was deposited at room temperature, whereas its oxidation took place during annealing at 1070 K. The Al 2O 3 thickness was monitored by means of Auger electron spectroscopy (AES). It was found that Al 2O 3 layer follows the structure of 0.5 nm thick Al 2O 3 film, although a tilting of Al 2O 3(1 1 1) surface plane with respect to NiAl(1 1 0) surface appeared after Al deposition.

  17. Erratum to: Study of the spin and parity of the Higgs boson in diboson decays with the ATLAS detector

    DOE PAGES

    Aad, G.; Abbott, B.; Abdallah, J.; ...

    2016-03-17

    This is an erratum to Eur. Phys. J.C. (2015) 75: 476. Unfortunately in the HTML of the article the authors, M. Ishino, T. Kunigo, T. Sumida and T. Tashiro, are assigned to the wrong affiliation. In the PDF of the article the assignment to the affiliation is correct.

  18. Erratum to: ATLAS Run 1 searches for direct pair production of third-generation squarks at the Large Hadron Collider ATLAS Collaboration

    DOE PAGES

    Aad, G.; Abbott, B.; Abdallah, J.; ...

    2016-03-17

    This is an erratum to Eur. Phys. J.C (2015) 75:510. Unfortunately in the HTML of the article the authors, M. Ishino, T. Kunigo, T. Sumida and T. Tashiro, are assigned to the wrong affiliation. In the PDF of the article the assignment to the affiliation is correct.

  19. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aad, G.; Abbott, B.; Abdallah, J.

    This is an erratum to Eur. Phys. J.C (2015) 75:510. Unfortunately in the HTML of the article the authors, M. Ishino, T. Kunigo, T. Sumida and T. Tashiro, are assigned to the wrong affiliation. In the PDF of the article the assignment to the affiliation is correct.

  20. Comment on 'The diatomic dication CuZn{sup 2+} in the gas phase' [J. Chem. Phys. 135, 034306 (2011)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fiser, Jiri; Diez, Reinaldo Pis; Franzreb, Klaus

    2013-02-21

    In this Comment, the density functional theory (DFT) calculations carried out by Diez et al. [J. Chem. Phys. 135, 034306 (2011)] are revised within the framework of the coupled-cluster single double triple method. These more sophisticated calculations allow us to show that the {sup 2}{Sigma}{sup +} electronic ground state of CuZn{sup 2+}, characterized as the metastable ground state by DFT calculations, is a repulsive state instead. The {sup 2}{Delta} and {sup 2}{Pi} metastable states of CuZn{sup 2+}, on the other hand, should be responsible for the formation mechanism of the dication through the near-resonant electron transfer CuZn{sup +}+ Ar{sup +}{yields}more » CuZn{sup 2+}+ Ar reaction.« less

  1. Slow dynamics and aging of a confined granular flow

    NASA Astrophysics Data System (ADS)

    Clement, Eric

    2004-03-01

    We present experimental results on slow flow properties of granular assemblies confined in a vertical column and driven upwards at a constant velocity V [1]. The wall roughness is much lower than the typical grain size. For monodisperse assemblies this study evidences at low velocities (1al. Phys. Rev. E 64, 060302 (2001); Phys. Rev. E 68, 031302 (2003). 2.E.Kolb et al Eur.Phys.J.B 8, 483 (1999.

  2. A multicharge ion source (Supernanogan) for the OLIS facility at ISAC/TRIUMF.

    PubMed

    Jayamanna, K; Wight, G; Gallop, D; Dube, R; Jovicic, V; Laforge, C; Marchetto, M; Leross, M; Louie, D; Laplante, R; Laxdal, R; McDonald, M; Wiebe, G J; Wang, V; Yan, F

    2010-02-01

    The Off-Line Ion Source (OLIS) [K. Jayamanna, D. Yuan, T. Kuo, M. MacDonald, P. Schmor, and G. Dutto, Rev. Sci. Instrum. 67, 1061 (1996); K. Jayamanna, Rev. Sci. Instrum. 79, 02711 (2008)] facility consists of a high voltage terminal containing a microwave cusp ion source, either a surface ion source or a hybrid surface-arc discharge ion source [K. Jayamanna and C. Vockenhuber, Rev. Sci. Instrum. 79, 02C712 (2008)], and an electrostatic switch that allows the selection of any one of the sources without mechanical intervention. These sources provide a variety of +1 beams up to mass 30 for Isotope Separator and ACcelerator (ISAC) [R. E. Laxdal, Nucl. Instrum. Methods Phys. Res. B 204, 400 (2003)] experiments, commissioning the accelerators, setting up the radioactive experiments, and for tuning the beam lines. The radio frequency quadrupole (RFQ) [M. Marchetto, Z. T. Ang, K. Jayamanna, R. E. Laxdal, A. Mitra, and V. Zvyagintsev, Eur. Phys. J. Spec. Top. 150, 241 (2005)] injector accelerator is a constant velocity machine designed to accept only 2 keV/u and the source extraction energy is limited to 60 kV. Further stripping is then needed downstream of the RFQ to inject the beam into the drift tube linac [M. Marchetto, Z. T. Ang, K. Jayamanna, R. E. Laxdal, A. Mitra, and V. Zvyagintsev, Eur. Phys. J. Spec. Top. 150, 241 (2005)] accelerator that requires A/q up to 6. Base on this constraints a multicharge ion source capable to deliver beams above mass 30 with A/q up to 6 was needed in order to reach full capability of the ISAC facility. A Supernanogan [C. Bieth et al., Nucleonika 48, S93 (2003)] multicharge ion source was then purchased from Pantechnik and was installed in the OLIS terminal. Commissioning and performance of the Supernanogan with some results such as emittance dependence of the charge states as well as charge state efficiencies are presented.

  3. Characterization of the Pathological and Biochemical Markers that Correlate to the Clinical Features of Autism

    DTIC Science & Technology

    2012-10-01

    Genet 1997;60:928–34 Ghaziuddin M, Sheldon S, Venkataraman S, et al. Autism associated with tetrasomy 15: A further report. Eur Child Adoles...article is prohibited. 22. Ghaziuddin M, Sheldon S, Venkataraman S, et al. Autism associated with tetrasomy 15: A further report. Eur Child Adolesc

  4. Special issue: diagnostics of atmospheric pressure microplasmas

    NASA Astrophysics Data System (ADS)

    Bruggeman, Peter; Czarnetzki, Uwe; Tachibana, Kunihide

    2013-11-01

    464004 [14] Sousa J S and Puech V 2013 J. Phys. D: Appl. Phys. 46 464005 [15] Takeda K et al 2013 J. Phys. D: Appl. Phys. 46 464006 [16] Vallade J and Massines F 2013 J. Phys. D: Appl. Phys. 46 464007 [17] Wang C and Wu W 2013 J. Phys. D: Appl. Phys. 46 464008 [18] Schröter S et al 2013 J. Phys. D: Appl. Phys. 46 464009 [19] Rusterholtz D L et al 2013 J. Phys. D: Appl. Phys. 46 464010 [20] Huang B-D et al 2013 J. Phys. D: Appl. Phys. 46 464011 [21] Pothiraja R et al 2013 J. Phys. D: Appl. Phys. 46 464012 [22] Marinov I et al 2013 J. Phys. D: Appl. Phys. 46 464013 [23] Akishev Y et al 2013 J. Phys. D: Appl. Phys. 46 464014 [24] Brandenburg R et al 2013 J. Phys. D: Appl. Phys. 46 464015 [25] Houlahan T J Jret al 2013 J. Phys. D: Appl. Phys. 46 464016 [26] Benedikt J et al 2013 J. Phys. D: Appl. Phys. 46 464017 [27] McKay K et al 2013 J. Phys. D: Appl. Phys. 46 464018 [28] Selected papers from the 2nd International Workshop on Microplasmas 2005 J. Phys. D: Appl. Phys. 38 1633-759 [29] Special issue: 3rd International Workshop on Microplasmas 2007 Control. Plasma Phys. 47 3-128 [30] Cluster issue on Microplasmas: 4th International Workshop on Microplasmas 2008 J. Phys. D: Appl. Phys. 41 1904001 [31] Microplasmas: scientific challenges and technological opportunities 2010 Eur. Phys. J. D 60 437-608 [32] Becker K H, Schoenbach K H and Eden J G 2006 J. Phys. D: Appl. Phys. 39 R55 [33] Iza F, Kim G J, Lee S M, Lee J K, Walsh J L, Zhang Y T and Kong M G 2008 Plasma Process. Polym. 5 322-44 [34] Tachibana K 2006 Trans. Electr. Electron. Eng. 1 145-55 [35] Samukawa S et al 2012 J. Phys. D: Appl. Phys. 45 253001

  5. Comment on “The two dimensional motion of a particle in an inverse square potential: Classical and quantum aspects” [J. Math. Phys. 54, 053509 (2013)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bietenholz, Wolfgang, E-mail: wolbi@nucleares.unam.mx; Chryssomalakos, Chryssomalis, E-mail: chryss@nucleares.unam.mx; Salgado, Marcelo, E-mail: marcelo@nucleares.unam.mx

    We comment on a fatal flaw in the analysis contained in the work of Martínez-y-Romero et al., [J. Math. Phys. 54, 053509 (2013)], which concerns the motion of a point particle in an inverse square potential, and show that most conclusions reached there are wrong. In particular, the manifestly senseless claim that, in the attractive potential case, no bounded orbits exist for negative energies, is traced to a sign error. Several more mistakes, both in the classical and the quantum cases, are pointed out.

  6. JEWEL 2.0.0: directions for use

    NASA Astrophysics Data System (ADS)

    Zapp, Korinna

    2014-02-01

    In this publication the first official release of the Jewel 2.0.0 code [The first version Jewel 1 (Zapp et al. in Eur Phys J C 60:617, 2009) could only treat elastic scattering explicitly and the code was never published, The code can be downloaded from the official Jewel homepage http://jewel.hepforge.org] is presented. Jewel is a Monte Carlo event generator simulating QCD jet evolution in heavy-ion collisions. It treats the interplay of QCD radiation and re-scattering in a medium with fully microscopic dynamics in a consistent perturbative framework with minimal assumptions. After a qualitative introduction into the physics of Jewel detailed information about the practical aspects of using the code is given. The code is available from the official Jewel homepage http://jewel.hepforge.org.

  7. The electron-phonon interaction with forward scattering peak is dominant in high T c superconductors of FeSe films on {{\\rm{SrTiO}}}_{3} (TiO2)

    NASA Astrophysics Data System (ADS)

    Kulić, M. L.; Dolgov, O. V.

    2017-01-01

    The theory of the electron-phonon interaction (EPI) with strong forward scattering peak (FSP) in an extreme delta-peak limit (Kulić and Zeyher 1994 Phys. Rev. B 49 4395; Kulić 2000 Phys. Rep. 38 1-264 Kulić and Dolgov 2005 Phys. Status Solidi b 242 151; Danylenko et al 1999 Eur. Phys. J. B 9 201) is recently applied in (Lee et al 2014 Nature 515 245; Rademaker et al 2016 New J. Phys. 18 022001; Wang et al 2016 Supercond. Sci. Technol. 29 054009) for the explanation of high {T}{{c}}(˜ 100 {{K}}) in a monolayer FeSe grown on {{{SrTiO}}}3 (Lee et al 2014 Nature 515 245) and TiO2 (Rebec et al 2016 arXiv:1606.09358v1) substrates. The EPI is due to a long-range dipolar electric field created by high-energy oxygen vibrations ({{Ω }}˜ 90 meV) at the interface (Lee et al 2014 Nature 515 245; Rademaker et al 2016 New J. Phys. 18 022001; Wang et al 2016 Supercond. Sci. Technol. 29 054009). In leading order (with respect to {T}{{c}0}/{{Ω }}) the mean-field critical temperature {T}{{c}0}={< {V}{{epi}}(q)> }q/4) ˜ {({{aq}}{{c}})}2{V}{{epi}}(0) and the gap {{{Δ }}}0=2{T}{{c}0\\text{}} are due to an interplay between the maximal EPI pairing potential {V}{{epi}}(0) and the FSP-width q c. For {T}{{c}0}˜ 100 K one has {{{Δ }}}0˜ 16 meV in a satisfactory agreement with ARPES experiments. In leading order T c0 is mass-independent and a very small oxygen isotope effect is expected in next to leading order. In clean systems T c0 for s-wave and d-wave pairing is degenerate but both are affected by non-magnetic impurities, which are pair-weakening in the s-channel and pair-breaking in the d-channel. The self-energy and replica bands at T = 0 and at the Fermi surface are calculated and compared with experimental results at T> 0 ( Rademaker et al 2016 New J. Phys. 18 022001; Wang et al 2016 Supercond. Sci. Technol. 29 054009). The EPI coupling constant {λ }{{m}}={< {V}{{epi}}(q)> }q/2{{Ω }} is mass-dependent ({M}1/2) and at ω (\\ll {{Ω }}) makes the slope of the self

  8. Electromagnetic Force on a Moving Dipole

    ERIC Educational Resources Information Center

    Kholmetskii, Alexander L.; Missevitch, Oleg V.; Yarman, T.

    2011-01-01

    We analyse the force acting on a moving dipole due to an external electromagnetic field and show that the expression derived in Vekstein (1997 "Eur. J. Phys." 18 113) is erroneous and suggest the correct equation for the description of this force. We also discuss the physical meaning of the relativistic transformation of current for a closed…

  9. Light Reflection from Water Surfaces Perturbed by Falling Rain Droplets

    ERIC Educational Resources Information Center

    Molesini, Giuseppe; Vannoni, Maurizio

    2009-01-01

    An account of peculiar light patterns produced by reflection in a pool under falling rain droplets was recently reported by Molesini and Vannoni (2008 Eur. J. Phys. 29 403-11). The mathematical approach, however, only covered the case of a symmetrical location of a light source and the observer's eyes with respect to the vertical of the falling…

  10. Comment on ‘A note on heat reservoirs and the like’

    NASA Astrophysics Data System (ADS)

    Anacleto, Joaquim; Ferreira, J. M.

    2017-07-01

    This comment addresses some points in the paper by de los Santos and López-Lacomba (2013 Eur. J. Phys. 34 659). More specifically, we clarify the use of the Clausius relation and argue that the proposed new definition of reversibility is flawed. Our motivation is the pedagogical need to clarify issues which, despite being subtle, are perfectly tractable.

  11. Chalcogen doping at anionic site: A scheme towards more dispersive valence band in CuAlO2

    NASA Astrophysics Data System (ADS)

    Mazumder, Nilesh; Sen, Dipayan; Chattopadhyay, Kalyan Kumar

    2013-02-01

    Using first-principles calculations, we propose to enhance the dispersion of the top of valence band at high-symmetry points by selective introduction of chalcogen (Ch) impurities at oxygen site. As ab-plane hole mobility of CuAlO2 is large enough to support a band-conduction model over a polaronic one at room temperature [M. S. Lee et al. Appl. Phys. Lett. 79, 2029, (2001); J. Tate et al. Phys. Rev. B 80, 165206, (2009)], we examine its electronic and optical properties normal to c-axis. Intrinsic indirectness of energy-gap at Γ-point can be effectively removed along with substantial increase in density of states near Fermi level (EF) upon Ch addition. This can be attributed to S 2p-Cu 3d interaction just at or below EF, which should result in significantly improved carrier mobility and conductivity profile for this important p-type TCO.

  12. Comment on “Stationary self-focusing of Gaussian laser beam in relativistic thermal quantum plasma” [Phys. Plasmas 20, 072703 (2013)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Habibi, M., E-mail: habibi.physics@gmail.com; Ghamari, F.

    2014-06-15

    Patil and Takale in their recent article [Phys. Plasmas 20, 072703 (2013)], by evaluating the quantum dielectric response in thermal quantum plasma, have modeled the relativistic self-focusing of Gaussian laser beam in a plasma. We have found that there are some important shortcomings and fundamental mistakes in Patil and Takale [Phys. Plasmas 20, 072703 (2013)] that we give a brief description about them and refer readers to important misconception about the use of the Fermi temperature in quantum plasmas, appearing in Patil and Takale [Phys. Plasmas 20, 072703 (2013)].

  13. Limits on the Majorana Neutrino Mass in the 0.1 eV Range

    NASA Astrophysics Data System (ADS)

    Baudis, L.; Dietz, A.; Heusser, G.; Klapdor-Kleingrothaus, H. V.; Krivosheina, I. V.; Kolb, St.; Majorovits, B.; Melnikov, V. F.; Päs, H.; Schwamm, F.; Strecker, H.; Alexeev, V.; Balysh, A.; Bakalyarov, A.; Belyaev, S. T.; Lebedev, V. I.; Zhukov, S.

    1999-07-01

    The Heidelberg-Moscow experiment gives the most stringent limit on the Majorana neutrino mass. After 24 kg yr of data with pulse shape measurements, we set a lower limit on the half-life of the 0νββ decay in 76Ge of T0ν1/2>=5.7×1025 yr at 90% C.L. (after PDG98 [C. Caso et al., Eur. Phys. J. C3, 1 (1998]), the sensitivity of the experiment being T0ν1/2>=1.6×1025 yr at 90% C.L. We thus exclude an effective Majorana neutrino mass greater than 0.2 eV (0.39 eV sensitivity), using the matrix elements of A. Staudt, K. Muto, and H. V. Klapdor-Kleingrothaus, Europhys. Lett. 13, 31 (1990). This limit sets strong constraints on degenerate neutrino mass models.

  14. Belief Propagation Algorithm for Portfolio Optimization Problems

    PubMed Central

    2015-01-01

    The typical behavior of optimal solutions to portfolio optimization problems with absolute deviation and expected shortfall models using replica analysis was pioneeringly estimated by S. Ciliberti et al. [Eur. Phys. B. 57, 175 (2007)]; however, they have not yet developed an approximate derivation method for finding the optimal portfolio with respect to a given return set. In this study, an approximation algorithm based on belief propagation for the portfolio optimization problem is presented using the Bethe free energy formalism, and the consistency of the numerical experimental results of the proposed algorithm with those of replica analysis is confirmed. Furthermore, the conjecture of H. Konno and H. Yamazaki, that the optimal solutions with the absolute deviation model and with the mean-variance model have the same typical behavior, is verified using replica analysis and the belief propagation algorithm. PMID:26305462

  15. Belief Propagation Algorithm for Portfolio Optimization Problems.

    PubMed

    Shinzato, Takashi; Yasuda, Muneki

    2015-01-01

    The typical behavior of optimal solutions to portfolio optimization problems with absolute deviation and expected shortfall models using replica analysis was pioneeringly estimated by S. Ciliberti et al. [Eur. Phys. B. 57, 175 (2007)]; however, they have not yet developed an approximate derivation method for finding the optimal portfolio with respect to a given return set. In this study, an approximation algorithm based on belief propagation for the portfolio optimization problem is presented using the Bethe free energy formalism, and the consistency of the numerical experimental results of the proposed algorithm with those of replica analysis is confirmed. Furthermore, the conjecture of H. Konno and H. Yamazaki, that the optimal solutions with the absolute deviation model and with the mean-variance model have the same typical behavior, is verified using replica analysis and the belief propagation algorithm.

  16. Improving Science Teacher Preparation through the APS PhysTEC and NSF Noyce Programs

    NASA Astrophysics Data System (ADS)

    Williams, Tasha; Tyler, Micheal; van Duzor, Andrea; Sabella, Mel

    2013-03-01

    Central to the recruitment of students into science teaching at a school like CSU, is a focus on the professional nature of teaching. The purpose of this focus is twofold: it serves to change student perceptions about teaching and it prepares students to become teachers who value continued professional development and value the science education research literature. The Noyce and PhysTEC programs at CSU place the professional nature of teaching front and center by involving students in education research projects, paid internships, attendance at conferences, and participation in a new Teacher Immersion Institute and a Science Education Journal Reading Class. This poster will focus on specific components of our teacher preparation program that were developed through these two programs. In addition we will describe how these new components provide students with diverse experiences in the teaching of science to students in the urban school district. Supported by the NSF Noyce Program (0833251) and the APS PhysTEC Program.

  17. The Potential Energy Density in Transverse String Waves Depends Critically on Longitudinal Motion

    ERIC Educational Resources Information Center

    Rowland, David R.

    2011-01-01

    The question of the correct formula for the potential energy density in transverse waves on a taut string continues to attract attention (e.g. Burko 2010 "Eur. J. Phys." 31 L71), and at least three different formulae can be found in the literature, with the classic text by Morse and Feshbach ("Methods of Theoretical Physics" pp 126-127) stating…

  18. On the Stable Limit Cycle of a Weight-Driven Pendulum Clock

    ERIC Educational Resources Information Center

    Llibre, J; Teixeira, M. A.

    2010-01-01

    In a recent paper (Denny 2002 Eur. J. Phys. 23 449-58), entitled "The pendulum clock: a venerable dynamical system", Denny showed that in a first approximation the steady-state motion of a weight-driven pendulum clock is shown to be a stable limit cycle. He placed the problem in a historical context and obtained an approximate solution using the…

  19. Rolling Reloaded

    ERIC Educational Resources Information Center

    Jones, Simon A.; Nieminen, John M.

    2008-01-01

    Not so long ago a new observation about rolling motion was described: for a rolling wheel, there is a set of points with instantaneous velocities directed at or away from the centre of the wheel; these points form a circle whose diameter connects the centre of the wheel to the wheel's point of contact with the ground (Sharma 1996 "Eur. J. Phys."…

  20. Electrodynamics of Moving Conductors in Magnetic Fields: Off the Beaten Track with Paul Lorrain

    ERIC Educational Resources Information Center

    Bringuier, E.

    2012-01-01

    The paper is about the appearance of space charge in an ohmic conductor moving in a magnetic field, as pointed out in this journal by Lorrain (1990 "Eur. J. Phys." 11 94-8) and earlier by van Bladel (1973 "Proc. IEEE" 61 260-8). The phenomenon is reinvestigated here in the light of energy balance considerations, in the particular case of a…

  1. Why do Scale-Free Networks Emerge in Nature? From Gradient Networks to Transport Efficiency

    NASA Astrophysics Data System (ADS)

    Toroczkai, Zoltan

    2004-03-01

    It has recently been recognized [1,2,3] that a large number of complex networks are scale-free (having a power-law degree distribution). Examples include citation networks [4], the internet [5], the world-wide-web [6], cellular metabolic networks [7], protein interaction networks [8], the sex-web [9] and alliance networks in the U.S. biotechnology industry [10]. The existence of scale-free networks in such diverse systems suggests that there is a simple underlying common reason for their development. Here, we propose that scale-free networks emerge because they ensure efficient transport of some entity. We show that for flows generated by gradients of a scalar "potential'' distributed on a network, non scale-free networks, e.g., random graphs [11], will become maximally congested, while scale-free networks will ensure efficient transport in the large network size limit. [1] R. Albert and A.-L. Barabási, Rev.Mod.Phys. 74, 47 (2002). [2] M.E.J. Newman, SIAM Rev. 45, 167 (2003). [3] S.N. Dorogovtsev and J.F.F. Mendes, Evolution of Networks: From Biological Nets to the Internet and WWW, Oxford Univ. Press, Oxford, 2003. [4] S. Redner, Eur.Phys.J. B, 4, 131 (1998). [5] M. Faloutsos, P. Faloutsos and C. Faloutsos Comp.Comm.Rev. 29, 251 (1999). [6] R. Albert, H. Jeong, and A.L. Barabási, Nature 401, 130 (1999). [7] H. Jeong et.al. Nature 407, 651 (2000). [8] H. Jeong, S. Mason, A.-L. Barabási and Z. N. Oltvai, Nature 411, 41 (2001). [9] F. Liljeros et. al. Nature 411 907 (2000). [10] W. W. Powell, D. R. White, K. W. Koput and J. Owen-Smith Am.J.Soc. in press. [11] B. Bollobás, Random Graphs, Second Edition, Cambridge University Press (2001).

  2. BrainPhys® increases neurofilament levels in CNS cultures, and facilitates investigation of axonal damage after a mechanical stretch-injury in vitro.

    PubMed

    Jackson, Travis C; Kotermanski, Shawn E; Jackson, Edwin K; Kochanek, Patrick M

    2018-02-01

    Neurobasal®/B27 is a gold standard culture media used to study primary neurons in vitro. An alternative media (BrainPhys®/SM1) was recently developed which robustly enhances neuronal activity vs. Neurobasal® or DMEM. To the best of our knowledge BrainPhys® has not been explored in the setting of neuronal injury. Here we characterized the utility of BrainPhys® in a model of in vitro mechanical-stretch injury. Primary rat cortical neurons were maintained in classic Neurobasal®, or sequentially maintained in Neurocult® followed by BrainPhys® (hereafter simply referred to as "BrainPhys® maintained neurons"). The levels of axonal markers and proteins involved in neurotransmission were compared on day in vitro 10 (DIV10). BrainPhys® maintained neurons had higher levels of GluN2B, GluR1, Neurofilament light/heavy chain (NF-L & NF-H), and protein phosphatase 2 A (PP2A) vs. neurons in Neurobasal®. Mechanical stretch-injury (50ms/54% biaxial stretch) to BrainPhys® maintained neurons modestly (albeit significantly) increased 24h lactate dehydrogenase (LDH) levels but markedly decreased axonal NF-L levels post-injury vs. uninjured controls or neurons given a milder 38% stretch-injury. Furthermore, two 54% stretch-injuries (in tandem) exacerbated 24h LDH release, increased α-spectrin breakdown products (SBDPs), and decreased Tau levels. Also, BrainPhys® maintained cultures had decreased markers of cell damage 24h after a single 54% stretch-injury vs. neurons in Neurobasal®. Finally, we tested the hypothesis that lentivirus mediated overexpression of the pro-death protein RBM5 exacerbates neuronal and/or axonal injury in primary CNS cultures. RBM5 overexpression vs. empty-vector controls increased 24h LDH release, and SBDP levels, after a single 54% stretch-injury but did not affect NF-L levels or Tau. BrainPhys® is a promising new reagent which facilities the investigation of molecular targets involved in axonal and/or neuronal injury in vitro. Copyright © 2017

  3. Reynolds number effects on the single-mode Richtmyer-Meshkov instability.

    PubMed

    Walchli, B; Thornber, B

    2017-01-01

    The Reynolds number effects on the nonlinear growth rates of the Richtmyer-Meshkov instability are investigated using two-dimensional numerical simulations. A decrease in Reynolds number gives an increased time to reach nonlinear saturation, with Reynolds number effects only significant in the range Re<256. Within this range there is a sharp change in instability properties. The bubble and spike amplitudes move towards equal size at lower Reynolds numbers and the bubble velocities decay faster than predicted by Sohn's model [S.-I. Sohn, Phys. Rev. E 80, 055302 (2009)PLEEE81539-375510.1103/PhysRevE.80.055302]. Predicted amplitudes show reasonable agreement with the existing theory of Carles and Popinet [P. Carles and S. Popinet, Phys. Fluids Lett. 13, 1833 (2001)10.1063/1.1377863; Eur. J. Mech. B 21, 511 (2002)EJBFEV0997-754610.1016/S0997-7546(02)01199-8] and Mikaelian [K. O. Mikaelian, Phys. Rev. E 47, 375 (1993)1063-651X10.1103/PhysRevE.47.375; K. O. Mikaelian, Phys. Rev. E 87, 031003 (2013)PLEEE81539-375510.1103/PhysRevE.87.031003], with the former being the closest match to the current computations.

  4. Reynolds number effects on the single-mode Richtmyer-Meshkov instability

    NASA Astrophysics Data System (ADS)

    Walchli, B.; Thornber, B.

    2017-01-01

    The Reynolds number effects on the nonlinear growth rates of the Richtmyer-Meshkov instability are investigated using two-dimensional numerical simulations. A decrease in Reynolds number gives an increased time to reach nonlinear saturation, with Reynolds number effects only significant in the range Re<256 . Within this range there is a sharp change in instability properties. The bubble and spike amplitudes move towards equal size at lower Reynolds numbers and the bubble velocities decay faster than predicted by Sohn's model [S.-I. Sohn, Phys. Rev. E 80, 055302 (2009), 10.1103/PhysRevE.80.055302]. Predicted amplitudes show reasonable agreement with the existing theory of Carles and Popinet [P. Carles and S. Popinet, Phys. Fluids Lett. 13, 1833 (2001), 10.1063/1.1377863; Eur. J. Mech. B 21, 511 (2002), 10.1016/S0997-7546(02)01199-8] and Mikaelian [K. O. Mikaelian, Phys. Rev. E 47, 375 (1993), 10.1103/PhysRevE.47.375; K. O. Mikaelian, Phys. Rev. E 87, 031003 (2013), 10.1103/PhysRevE.87.031003], with the former being the closest match to the current computations.

  5. Inverse statistics in the foreign exchange market

    NASA Astrophysics Data System (ADS)

    Jensen, M. H.; Johansen, A.; Petroni, F.; Simonsen, I.

    2004-09-01

    We investigate intra-day foreign exchange (FX) time series using the inverse statistic analysis developed by Simonsen et al. (Eur. Phys. J. 27 (2002) 583) and Jensen et al. (Physica A 324 (2003) 338). Specifically, we study the time-averaged distributions of waiting times needed to obtain a certain increase (decrease) ρ in the price of an investment. The analysis is performed for the Deutsch Mark (DM) against the US for the full year of 1998, but similar results are obtained for the Japanese Yen against the US. With high statistical significance, the presence of “resonance peaks” in the waiting time distributions is established. Such peaks are a consequence of the trading habits of the market participants as they are not present in the corresponding tick (business) waiting time distributions. Furthermore, a new stylized fact, is observed for the (normalized) waiting time distribution in the form of a power law Pdf. This result is achieved by rescaling of the physical waiting time by the corresponding tick time thereby partially removing scale-dependent features of the market activity.

  6. Inhomogeneous Heisenberg spin chain and quantum vortex filament as non-holonomically deformed NLS systems

    NASA Astrophysics Data System (ADS)

    Abhinav, Kumar; Guha, Partha

    2018-03-01

    Through the Hasimoto map, various dynamical systems can be mapped to different integrodifferential generalizations of Nonlinear Schrödinger (NLS) family of equations some of which are known to be integrable. Two such continuum limits, corresponding to the inhomogeneous XXX Heisenberg spin chain [J. Phys. C 15, L1305 (1982)] and that of a thin vortex filament moving in a superfluid with drag [Eur. Phys. J. B 86, 275 (2013) 86; Phys. Rev. E 91, 053201 (2015)], are shown to be particular non-holonomic deformations (NHDs) of the standard NLS system involving generalized parameterizations. Crucially, such NHDs of the NLS system are restricted to specific spectral orders that exactly complements NHDs of the original physical systems. The specific non-holonomic constraints associated with these integrodifferential generalizations additionally posses distinct semi-classical signature.

  7. Molecular-dynamics simulations of thin films with a free surface

    NASA Astrophysics Data System (ADS)

    Peter, Simone; Meyer, Hendrik; Baschnagel, Joerg

    2007-03-01

    We present results [1,2] from molecular-dynamics simulations for a model of non-entangled short polymer chains in a free standing and a supported film geometry. We investigate the influence of confinement on static and dynamic properties of the melt. We find that the relaxation at the surfaces is faster in comparison to the bulk. We perform a layer-resolved analysis of the dynamics and show that it is possible to associate a gradient in critical temperatures Tc(y) with the gradient in the relaxation dynamics. This finding is in qualitative agreement with experimental results on supported polystyrene (PS) films [Ellison et al, Nat. Mater. 2, 695 (2003)]. Furthermore we show that the y-dependence of Tc(y) can be expressed in terms of the depression of Tc(h), the global Tc for a film of thickness h, if we assume that Tc(h) is the arithmetic mean of Tc(y) and parameterize the depression of Tc(h) by Tc(h)=Tc/(1+h0/h), a formula suggested by Herminghaus et al [Eur. Phys. J E 5, 531 (2001)] for the reduction of the glass transition temperature in supported PS films. We demonstrate the validity of this formula by comparing our simulation results to results from other simulations and experiments. [1] S. Peter, H. Meyer and J. Baschnagel, J. Polym. Sci. B, 44, 2951 (2006) [2] S. Peter, H. Meyer, J. Baschnagel and R, Seemann, J. Phys: Condens. Matter (2007)

  8. The analysis of senior high school students' physics HOTS in Bantul District measured using PhysReMChoTHOTS

    NASA Astrophysics Data System (ADS)

    Istiyono, Edi

    2017-08-01

    The purpose of this research is to describe the results of higher order thinking skills in physics (PhysHOTS) measurement including: (1) percentage of PhysHOTS level and (2) percentage of the domination of response in the category of students in each analyzing, evaluating, and creating skill. There were 404 10th grade students in Bantul District as the respondents of this research. The instrument used for measurement was PhysReMChoTHOTS. It was divided into two sets consisting of 44 items and including 8 anchor items stated valid by a Physicist, Physics Education Expert, and Physics Education Measurement Expert. The instrument was fit to PCM. The reliability coefficient of this test is 0.71, while the difficulty index of the items ranges from -0.61 to 0.51. The results of the measurement show that: (1) The percentage of each category of PhysHOTS for the 10th grade students in Bantul District for the very low, low, medium, high, and very high category is 4.75 %, 40.30 %, 33.45 %, 19.50 %, and 2.00 %, respectively; and (2) The order in analyzing skills, starts from the weakest, is attributing, differentiating and organizing. The order in evaluating skills, starts from the weakest, is critiquing and checking. Meanwhile, the order in creating skills, starts from the weakest, is producing, planning, and generating.

  9. Shock compression response of cold-rolled Ni/Al multilayer composites

    NASA Astrophysics Data System (ADS)

    Specht, Paul E.; Weihs, Timothy P.; Thadhani, Naresh N.

    2017-01-01

    Uniaxial strain, plate-on-plate impact experiments were performed on cold-rolled Ni/Al multilayer composites and the resulting Hugoniot was determined through time-resolved measurements combined with impedance matching. The experimental Hugoniot agreed with that previously predicted by two dimensional (2D) meso-scale calculations [Specht et al., J. Appl. Phys. 111, 073527 (2012)]. Additional 2D meso-scale simulations were performed using the same computational method as the prior study to reproduce the experimentally measured free surface velocities and stress profiles. These simulations accurately replicated the experimental profiles, providing additional validation for the previous computational work.

  10. CORRIGENDUM: Editorial note

    NASA Astrophysics Data System (ADS)

    Rae, A. I. M.

    2002-07-01

    The first sentence of this comment should read as follows: It has been drawn to our attention that a comment published in our January issue [1] contains the statement that `the functions {1, sin2 α, cos 2α}...are clearly linearly independent...'. References [1]Figueroa-Navarro C 2002 A comment on Gluskin's note on J D Jackson's Classical Electrodynamics Eur. J. Phys. 23 L1-3

  11. Collaborative study for the establishment of the Ph. Eur. Hepatitis E virus RNA for NAT testing biological reference preparation batch 1.

    PubMed

    Baylis, S A; Terao, E; Blümel, J; Hanschmann, K-M O

    2017-01-01

    A new European Pharmacopoeia (Ph. Eur.) biological reference preparation (BRP) had to be established further to the decision to include nucleic acid testing (NAT) for the detection of hepatitis E virus (HEV) RNA in the monograph Human plasma (pooled and treated for virus inactivation) (1646). To this purpose, an international collaborative study was launched in the framework of the Biological Standardisation Programme (BSP) of the European Directorate for the Quality of Medicines & HealthCare (EDQM) and the Commission of the European Union (EU). The study was run in conjunction with the establishment of the 1 st World Health Organization (WHO) international reference panel (IRP) for hepatitis E virus RNA genotypes (8578/13). Twenty-three laboratories used in-house developed and commercially available assays to calibrate a lyophilised candidate BRP prepared from a HEV 3f strain positive human plasma against the 1 st WHO International Standard (IS) for HEV RNA (6329/10). Results from quantitative and qualitative assays were in good agreement and were combined to calculate an assigned potency. Real-time stability studies indicated that the candidate BRP is very stable at lower temperatures and is thus suitable for long-term use. Based on these results, in February 2016, the Ph. Eur. Commission adopted the candidate material as the hepatitis E virus RNA for NAT testing BRP batch 1, with an assigned unitage of 2.1 × 10 4 IU/vial (4.32 log 10 IU/vial).

  12. Pre-Town Meeting on spin physics at an Electron-Ion Collider

    NASA Astrophysics Data System (ADS)

    Aschenauer, Elke-Caroline; Balitsky, Ian; Bland, Leslie; Brodsky, Stanley J.; Burkardt, Matthias; Burkert, Volker; Chen, Jian-Ping; Deshpande, Abhay; Diehl, Markus; Gamberg, Leonard; Grosse Perdekamp, Matthias; Huang, Jin; Hyde, Charles; Ji, Xiangdong; Jiang, Xiaodong; Kang, Zhong-Bo; Kubarovsky, Valery; Lajoie, John; Liu, Keh-Fei; Liu, Ming; Liuti, Simonetta; Melnitchouk, Wally; Mulders, Piet; Prokudin, Alexei; Tarasov, Andrey; Qiu, Jian-Wei; Radyushkin, Anatoly; Richards, David; Sichtermann, Ernst; Stratmann, Marco; Vogelsang, Werner; Yuan, Feng

    2017-04-01

    A polarized ep/ eA collider (Electron-Ion Collider, or EIC), with polarized proton and light-ion beams and unpolarized heavy-ion beams with a variable center-of-mass energy √{s} ˜ 20 to ˜ 100 GeV (upgradable to ˜ 150 GeV) and a luminosity up to ˜ 10^{34} cm-2s-1, would be uniquely suited to address several outstanding questions of Quantum Chromodynamics, and thereby lead to new qualitative and quantitative information on the microscopic structure of hadrons and nuclei. During this meeting at Jefferson Lab we addressed recent theoretical and experimental developments in the spin and the three-dimensional structure of the nucleon (sea quark and gluon spatial distributions, orbital motion, polarization, and their correlations). This mini-review contains a short update on progress in these areas since the EIC White paper (A. Accardi et al., Eur. Phys. J. A 52, 268 (2016)).

  13. A New Method to Retrieve the Orbital Parameters of the Galilean Satellites Using Small Telescopes: A Teaching Experiment

    NASA Astrophysics Data System (ADS)

    Sanchez-Lavega, Agustin; Ordoñez-Etxebarria, Iñaki; del Rio-Gaztelurrutia, Teresa

    2014-11-01

    We show in this communication how it is possible to deduce the radius of the orbits of Galilean satellites around Jupiter using a small number of well-planned observations. This allows the instructor to propose a complete student activity that involves planning an observation, the observation itself, processing and analyzing the images and deduction of relevant magnitudes [1]. This work was performed in the Aula EspaZio Gela under the Master in Space Science and Technology [2].References[1] I. Ordoñez-Etxebarria, T. del Río Gaztelurrutia and A. Sánchez Lavega, European Journal of Physics, Eur. J. Phys., 35, 045020 (14pp), (2014)[2] A. Sánchez-Lavega et al., European Journal of Engineering Education, doi:10.1080/03043797.2013.788611 (2013)AcknowledgementsThis work was supported by a grant from Diputaciõn Foral de Bizkaia — Bizkaiko Foru Aldundia to the Aula Espazio Gela.

  14. Scheme for implementing perfect quantum teleportation with four-qubit entangled states in cavity quantum electrodynamics

    NASA Astrophysics Data System (ADS)

    Tang, Jing-Wu; Zhao, Guan-Xiang; He, Xiong-Hui

    2011-05-01

    Recently, Peng et al. [2010 Eur. Phys. J. D 58 403] proposed to teleport an arbitrary two-qubit state with a family of four-qubit entangled states, which simultaneously include the tensor product of two Bell states, linear cluster state and Dicke-class state. This paper proposes to implement their scheme in cavity quantum electrodynamics and then presents a new family of four-qubit entangled state |Ω4>1234. It simultaneously includes all the well-known four-qubit entangled states which can be used to teleport an arbitrary two-qubit state. The distinct advantage of the scheme is that it only needs a single setup to prepare the whole family of four-qubit entangled states, which will be very convenient for experimental realization. After discussing the experimental condition in detail, we show the scheme may be feasible based on present technology in cavity quantum electrodynamics.

  15. Comment on "Electron spin resonance studies in β-FeSi2 crystals" [J. Appl. Phys. 80, 1678 (1996)

    NASA Astrophysics Data System (ADS)

    Irmscher, K.; Gehlhoff, W.; Lange, H.

    1997-06-01

    In a recent article [J. Appl. Phys. 80, 1678 (1996)] Aksenov et al. reported on electron paramagnetic resonance (EPR) studies in β-FeSi2 crystals grown by chemical vapor transport. They did not perform a rigorous measurement of the angular variation of the EPR line positions. Consequently, there has been a drastic loss of information and most of their conclusions turn out to be erroneous. It is shown that the anisotropic signals (Ai,Bi) do not arise from spin triplet states but from centers with S=1/2 and their origins are not Ni2+ ions but Ni+ (Ai) and Cr- (Bi) ions substituting for Fe on one of its two inequivalent lattice sites. The analysis of the line structure of the isotropic signal (C) is incorrect and hence, the structure cannot be attributed to a ligand hyperfine interaction with four iron atoms. Finally, the determination of an acceptor activation energy from the temperature dependence of the C signal is not justified since no correction for the EPR intensity dependence due to the thermal population difference of the Zeeman levels was included.

  16. Interactions of Ultracold Impurity Particles with Bose-Einstein Condensates

    DTIC Science & Technology

    2015-06-23

    Lukin et al ., Phys. Rev. Lett. 87, 037901 (2001). [2] D. Jaksch et al ., Phys. Rev. Lett. 85, 2208 (2000). [3] L. Isenhower et al ., Phys. Rev. Lett...104, 010503 (2010). [4] T. Wilk et al ., Phys. Rev. Lett. 104, 010502 (2010). [5] I. Mourachko et al ., Phys. Rev. Lett. 80, 253 (1998). [6] W. R...Phys. 12, 103044 (2010). [12] R. M. W. van Bijnen et al ., J. Phys. B 44, 184008 (2011). [13] I. Lesanovsky, Phys. Rev. Lett. 106, 025301 (2011). [14] E

  17. Entropy Production of Entirely Diffusional Laplacian Transfer and the Possible Role of Fragmentation of the Boundaries

    NASA Astrophysics Data System (ADS)

    Karamanos, K.; Mistakidis, S. I.; Massart, T. J.; Mistakidis, I. S.

    2015-06-01

    The entropy production and the variational functional of a Laplacian diffusional field around the first four fractal iterations of a linear self-similar tree (von Koch curve) is studied analytically and detailed predictions are stated. In a next stage, these predictions are confronted with results from numerical resolution of the Laplace equation by means of Finite Elements computations. After a brief review of the existing results, the range of distances near the geometric irregularity, the so-called "Near Field", a situation never studied in the past, is treated exhaustively. We notice here that in the Near Field, the usual notion of the active zone approximation introduced by Sapoval et al. [M. Filoche and B. Sapoval, Transfer across random versus deterministic fractal interfaces, Phys. Rev. Lett. 84(25) (2000) 5776;1 B. Sapoval, M. Filoche, K. Karamanos and R. Brizzi, Can one hear the shape of an electrode? I. Numerical study of the active zone in Laplacian transfer, Eur. Phys. J. B. Condens. Matter Complex Syst. 9(4) (1999) 739-753.]2 is strictly inapplicable. The basic new result is that the validity of the active-zone approximation based on irreversible thermodynamics is confirmed in this limit, and this implies a new interpretation of this notion for Laplacian diffusional fields.

  18. Physics of the spin gap in the S=1/2 Heisenberg antiferromagnet on kagome

    NASA Astrophysics Data System (ADS)

    Tchernyshyov, Oleg

    2009-03-01

    A combination of low spin and strong frustration makes the S=1/2 Heisenberg antiferromagnet on kagome a likely candidate for an unusual ground state and elementary excitations. Exact-diagonalization studies [1] on finite clusters point to a lack of magnetic order in the ground state and to an energy gap of order J/20 for S=1 excitations. The exact nature of the ground state and elementary excitations remains a subject of vigorous debate. Among the proposed ground states are chiral [2] and non-chiral [3] spin liquids and a valence-bond crystal (VBC) [4-5]; spin excitations range from deconfined spinons with a Bose [6] or Fermi statistics [2-3] to magnons [7]. We show that the system behaves as a collection of spinons, quasiparticles with S=1/2 and Fermi statistics, whose motion disturbs valence-bond order. Attraction between spinons, mediated by exchange, binds them into small, massive pairs of S=0 with a binding energy of 0.06 J [8]. The pair formation strongly suppresses the motion of individual spinons and makes the survival of the Singh-Huse VBC plausible. A spin excitation amounts to breaking up a pair into two (nearly) free spinons with S=1. The survival of the VBC is expected to lead to spinon confinement; however, small energy differences between various valence-bond configurations would make the confinement length large. [4pt] [1] Ch. Waldtmann et al., Eur. Phys. J. B 2, 510 (1998).[0pt] [2] J. B. Marston and C. Zeng, J. Appl. Phys. 69, 5962 (1991).[0pt] [3] M. B. Hastings, Phys. Rev. B 63, 014413 (2000).[0pt] [4] P. Nikolic and T. Senthil, Phys. Rev. B 68, 214415 (2003).[0pt] [5] R. R. P. Singh and D. A. Huse, Phys. Rev. B 76, 180407 (2007).[0pt] [6] S. Sachdev, Phys. Rev. B 45, 12377 (1992).[0pt] [7] R. R. P. Singh and D. A. Huse, arXiv:0801.2735. [0pt] [8] Z. Hao and O. Tchernyshyov, the subsequent talk.

  19. Beyond detection: biological physics informing progression and treatment of cancer Beyond detection: biological physics informing progression and treatment of cancer

    NASA Astrophysics Data System (ADS)

    Newman, T. J.; Thompson, A. M.

    2012-12-01

    The full text of the Preface is given in the PDF file. References [1] Kaur P et al 2012 Phys. Biol. 9 065001 [2] Lobikin M et al 2012 Phys. Biol. 9 065002 [3] Tanner K 2012 Phys. Biol. 9 065003 [4] Liu S V et al 2012 Phys. Biol. 9 065004 [5] Liao D et al 2012 Phys. Biol. 9 065005 [6] Liao D et al 2012 Phys. Biol. 9 065006 [7] Orlando P A et al 2012 Phys. Biol. 9 065007

  20. Structure of V2AlC studied by theory and experiment

    NASA Astrophysics Data System (ADS)

    Schneider, Jochen M.; Mertens, Raphael; Music, Denis

    2006-01-01

    We have studied V2AlC (space group P63/mmc, prototype Cr2AlC) by ab initio calculations. The density of states (DOS) of V2AlC for antiferromagnetic, ferromagnetic, and paramagnetic configurations have been discussed. According to the analysis of DOS and cohesive energy, no significant stability differences between spin-polarized and non-spin-polarized configurations were found. Based on the partial DOS analysis, V2AlC can be classified as a strongly coupled nanolaminate according to our previous work [Z. Sun, D. Music, R. Ahuja, S. Li, and J. M. Schneider, Phys. Rev. B 70, 092102 (2004)]. Furthermore, this phase has been synthesized in the form of thin films by magnetron sputtering. The equilibrium volume, determined by x-ray diffraction, is in good agreement with the theoretical data, implying that ab initio calculations provide an accurate description of V2AlC.

  1. Using the PhysX engine for physics-based virtual surgery with force feedback.

    PubMed

    Maciel, Anderson; Halic, Tansel; Lu, Zhonghua; Nedel, Luciana P; De, Suvranu

    2009-09-01

    The development of modern surgical simulators is highly challenging, as they must support complex simulation environments. The demand for higher realism in such simulators has driven researchers to adopt physics-based models, which are computationally very demanding. This poses a major problem, since real-time interactions must permit graphical updates of 30 Hz and a much higher rate of 1 kHz for force feedback (haptics). Recently several physics engines have been developed which offer multi-physics simulation capabilities, including rigid and deformable bodies, cloth and fluids. While such physics engines provide unique opportunities for the development of surgical simulators, their higher latencies, compared to what is necessary for real-time graphics and haptics, offer significant barriers to their use in interactive simulation environments. In this work, we propose solutions to this problem and demonstrate how a multimodal surgical simulation environment may be developed based on NVIDIA's PhysX physics library. Hence, models that are undergoing relatively low-frequency updates in PhysX can exist in an environment that demands much higher frequency updates for haptics. We use a collision handling layer to interface between the physical response provided by PhysX and the haptic rendering device to provide both real-time tissue response and force feedback. Our simulator integrates a bimanual haptic interface for force feedback and per-pixel shaders for graphics realism in real time. To demonstrate the effectiveness of our approach, we present the simulation of the laparoscopic adjustable gastric banding (LAGB) procedure as a case study. To develop complex and realistic surgical trainers with realistic organ geometries and tissue properties demands stable physics-based deformation methods, which are not always compatible with the interaction level required for such trainers. We have shown that combining different modelling strategies for behaviour, collision and

  2. Ab initio 27Al NMR chemical shifts and quadrupolar parameters for Al2O3 phases and their precursors

    NASA Astrophysics Data System (ADS)

    Ferreira, Ary R.; Küçükbenli, Emine; Leitão, Alexandre A.; de Gironcoli, Stefano

    2011-12-01

    The gauge-including projector augmented wave (GIPAW) method, within the density functional theory (DFT) generalized gradient approximation (GGA) framework, is applied to compute solid state NMR parameters for 27Al in the α, θ, and κ aluminium oxide phases and their gibbsite and boehmite precursors. The results for well established crystalline phases compare very well with available experimental data and provide confidence in the accuracy of the method. For γ-alumina, four structural models proposed in the literature are discussed in terms of their ability to reproduce the experimental spectra also reported in the literature. Among the considered models, the Fd3¯m structure proposed by Paglia [Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.71.224115 71, 224115 (2005)] shows the best agreement. We attempt to link the theoretical NMR parameters to the local geometry. Chemical shifts depend on coordination number but no further correlation is found with geometrical parameters. Instead, our calculations reveal that, within a given coordination number, a linear correlation exists between chemical shifts and Born effective charges.

  3. Hydrogen adsorption strength and sites in the metal organic framework MOF5: Comparing experiment and model calculations

    NASA Astrophysics Data System (ADS)

    Mulder, F. M.; Dingemans, T. J.; Schimmel, H. G.; Ramirez-Cuesta, A. J.; Kearley, G. J.

    2008-07-01

    Hydrogen adsorption in porous, high surface area, and stable metal organic frameworks (MOF's) appears a novel route towards hydrogen storage materials [N.L. Rosi, J. Eckert, M. Eddaoudi, D.T. Vodak, J. Kim, M. O'Keeffe, O.M. Yaghi, Science 300 (2003) 1127; J.L.C. Rowsell, A.R. Millward, K. Sung Park, O.M. Yaghi, J. Am. Chem. Soc. 126 (2004) 5666; G. Ferey, M. Latroche, C. Serre, F. Millange, T. Loiseau, A. Percheron-Guegan, Chem. Commun. (2003) 2976; T. Loiseau, C. Serre, C. Huguenard, G. Fink, F. Taulelle, M. Henry, T. Bataille, G. Férey, Chem. Eur. J. 10 (2004) 1373]. A prerequisite for such materials is sufficient adsorption interaction strength for hydrogen adsorbed on the adsorption sites of the material because this facilitates successful operation under moderate temperature and pressure conditions. Here we report detailed information on the geometry of the hydrogen adsorption sites, based on the analysis of inelastic neutron spectroscopy (INS). The adsorption energies for the metal organic framework MOF5 equal about 800 K for part of the different sites, which is significantly higher than for nanoporous carbon materials (˜550 K) [H.G. Schimmel, G.J. Kearley, M.G. Nijkamp, C.T. Visser, K.P. de Jong, F.M. Mulder, Chem. Eur. J. 9 (2003) 4764], and is in agreement with what is found in first principles calculations [T. Sagara, J. Klassen, E. Ganz, J. Chem. Phys. 121 (2004) 12543; F.M. Mulder, T.J. Dingemans, M. Wagemaker, G.J. Kearley, Chem. Phys. 317 (2005) 113]. Assignments of the INS spectra is realized using comparison with independently published model calculations [F.M. Mulder, T.J. Dingemans, M. Wagemaker, G.J. Kearley, Chem. Phys. 317 (2005) 113] and structural data [T. Yildirim, M.R. Hartman, Phys. Rev. Lett. 95 (2005) 215504].

  4. Toward quantum superposition of living organisms

    NASA Astrophysics Data System (ADS)

    Romero-Isart, Oriol; Juan, Mathieu L.; Quidant, Romain; Cirac, J. Ignacio

    2010-03-01

    The most striking feature of quantum mechanics is the existence of superposition states, where an object appears to be in different situations at the same time. The existence of such states has been previously tested with small objects, such as atoms, ions, electrons and photons (Zoller et al 2005 Eur. Phys. J. D 36 203-28), and even with molecules (Arndt et al 1999 Nature 401 680-2). More recently, it has been shown that it is possible to create superpositions of collections of photons (Deléglise et al 2008 Nature 455 510-14), atoms (Hammerer et al 2008 arXiv:0807.3358) or Cooper pairs (Friedman et al 2000 Nature 406 43-6). Very recent progress in optomechanical systems may soon allow us to create superpositions of even larger objects, such as micro-sized mirrors or cantilevers (Marshall et al 2003 Phys. Rev. Lett. 91 130401; Kippenberg and Vahala 2008 Science 321 1172-6 Marquardt and Girvin 2009 Physics 2 40; Favero and Karrai 2009 Nature Photon. 3 201-5), and thus to test quantum mechanical phenomena at larger scales. Here we propose a method to cool down and create quantum superpositions of the motion of sub-wavelength, arbitrarily shaped dielectric objects trapped inside a high-finesse cavity at a very low pressure. Our method is ideally suited for the smallest living organisms, such as viruses, which survive under low-vacuum pressures (Rothschild and Mancinelli 2001 Nature 406 1092-101) and optically behave as dielectric objects (Ashkin and Dziedzic 1987 Science 235 1517-20). This opens up the possibility of testing the quantum nature of living organisms by creating quantum superposition states in very much the same spirit as the original Schrödinger's cat 'gedanken' paradigm (Schrödinger 1935 Naturwissenschaften 23 807-12, 823-8, 844-9). We anticipate that our paper will be a starting point for experimentally addressing fundamental questions, such as the role of life and consciousness in quantum mechanics.

  5. iNR-PhysChem: A Sequence-Based Predictor for Identifying Nuclear Receptors and Their Subfamilies via Physical-Chemical Property Matrix

    PubMed Central

    Xiao, Xuan; Wang, Pu; Chou, Kuo-Chen

    2012-01-01

    Nuclear receptors (NRs) form a family of ligand-activated transcription factors that regulate a wide variety of biological processes, such as homeostasis, reproduction, development, and metabolism. Human genome contains 48 genes encoding NRs. These receptors have become one of the most important targets for therapeutic drug development. According to their different action mechanisms or functions, NRs have been classified into seven subfamilies. With the avalanche of protein sequences generated in the postgenomic age, we are facing the following challenging problems. Given an uncharacterized protein sequence, how can we identify whether it is a nuclear receptor? If it is, what subfamily it belongs to? To address these problems, we developed a predictor called iNR-PhysChem in which the protein samples were expressed by a novel mode of pseudo amino acid composition (PseAAC) whose components were derived from a physical-chemical matrix via a series of auto-covariance and cross-covariance transformations. It was observed that the overall success rate achieved by iNR-PhysChem was over 98% in identifying NRs or non-NRs, and over 92% in identifying NRs among the following seven subfamilies: NR1thyroid hormone like, NR2HNF4-like, NR3estrogen like, NR4nerve growth factor IB-like, NR5fushi tarazu-F1 like, NR6germ cell nuclear factor like, and NR0knirps like. These rates were derived by the jackknife tests on a stringent benchmark dataset in which none of protein sequences included has pairwise sequence identity to any other in a same subset. As a user-friendly web-server, iNR-PhysChem is freely accessible to the public at either http://www.jci-bioinfo.cn/iNR-PhysChem or http://icpr.jci.edu.cn/bioinfo/iNR-PhysChem. Also a step-by-step guide is provided on how to use the web-server to get the desired results without the need to follow the complicated mathematics involved in developing the predictor. It is anticipated that iNR-PhysChem may become a useful high throughput tool

  6. Response to ''Comment on 'Terahertz wave generation by upper hybrid wave''' [Phys. Plasmas 18, 074701 (2011)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Singh, Monika; Kumar, Sanjay; Sharma, R. P.

    2011-07-15

    The comment by Stenflo and Brodin mentions two points in our recently published paper [M. Singh, S. Kumar, and R. P. Sharma, Phys. Plasmas 18, 022304 (2011)]. We have given the appropriate reply for the same here.

  7. Phys21:Preparing Physics Students for 21st Century Careers

    NASA Astrophysics Data System (ADS)

    McCormack, Elizabeth

    2017-04-01

    The Phys21: Preparing Physics Students for 21st Century Careersreport was commissioned by the APS and the AAPT and prepared by the Joint Task Force on Undergraduate Physics Programs (J-TUPP). It addresses the question: What skills and knowledge should the next generation of undergraduate physics majors possess to be well prepared for a diverse set of careers? J-TUPP members were particularly interested to understand better the needs of students who do not plan to pursue academic research careers. The major findings of the report and a summary of the guidelines that were developed for revising the undergraduate curriculum, addressing the needs of an increasingly diverse population of students, providing professional skills development, and enhancing student engagement through high impact teaching practices will be presented.

  8. Preface: phys. stat. sol. (b) 241/9

    NASA Astrophysics Data System (ADS)

    Morawetz, Klaus

    2004-07-01

    Modelling and Simulation in Molecular Systems, Mesoscopic Structures, and Material Science was the title of a workshop held at the University of Technology in Chemnitz from 21 to 23 April 2004. This workshop coincided with the 50th birthday of Michael Schreiber. Therefore, the idea to publish a special issue is supported by two good reasons. First, a topical collection is appropriate for giving an overview about a field and to initiate further studies. This is one intention of the present issue. Second, the birthday is a suitable occasion for reflecting on the status of the different fields where Michael Schreiber has been active himself. Motivated by the characteristic name of the workshop (MS4), which expresses the broad range of his activities, the contributions are grouped into three main chapters: Disorder and Interaction, Phase Transitions and Criticality, and Transport Properties.The first part starts with the currently intensively discussed topic of composite Fermions in the paper by B. Kramer et al. This method of rewriting correlations as new quasiparticles has amongst other things the merit of explaining such exciting phenomena as the fractional quantum Hall effect. The methodological questions of Ward identities, causality, and conservation laws are the focus of the systematic investiga-tion in the second article by V. Janis et al. which concentrates on the problem of disorder and configura-tional averaging. The interplay between disorder and correlation is treated in the third contribution by C. Schuster et al., where different theoretical methods are tested on the problem of Friedel oscillations within the one-dimensional Heisenberg and Hubbard model. In the next contribution, M. Berciu et al. focus on localization as one consequence of disorder. The localized and extended electronic states are treated, together with the magnetic degrees of freedom, like spin waves. One of the astonishing consequence of localiza-tion is the observation of resonant

  9. Infrared

    NASA Astrophysics Data System (ADS)

    Vollmer, M.

    2013-11-01

    techniques such as attenuated total reflectance [6]. The two final papers deal with what seem to be wholly different scientific fields [7, 8]. One paper describes SOFIA, an aeroplane-based astronomical observatory covering the whole IR range [7], while the other represents a small review of the quite new topic of terahertz physics at the upper end of the IR spectral range, from around 30 µm to 3 mm wavelength, and its many applications in science and industry [8]. Although artificially separated, all these fields use similar kinds of detectors, similar kinds of IR sources and similar technologies, while the instruments use the same physical principles. We are convinced that the field of infrared physics will develop over the next decade in the same dynamic way as during the last, and this special issue may serve as starting point for regular submissions on the topic. At any rate, it shines a light on this fascinating and many-faceted subject, which started more than 200 years ago. References [1] Mangold K, Shaw J A and Vollmer M 2013 The physics of near-infrared photography Eur. J. Phys. 34 S51-71 [2] Vollmer M and Möllmann K-P 2013 Characterization of IR cameras in student labs Eur. J. Phys. 34 S73-90 [3] Ibarra-Castanedo C, Tarpani J R and Maldague X P V 2013 Nondestructive testing with thermography Eur. J. Phys. 34 S91-109 [4] Shaw J A and Nugent P W 2013 Physics principles in radiometric infrared imaging of clouds in the atmosphere Eur. J. Phys. 34 S111-21 [5] Möllmann K-P and Vollmer M 2013 Fourier transform infrared spectroscopy in physics laboratory courses Eur. J. Phys. 34 S123-37 [6] Heise H M, Fritzsche J, Tkatsch H, Waag F, Karch K, Henze K, Delbeck S and Budde J 2013 Recent advances in mid- and near-infrared spectroscopy with applications for research and teaching, focusing on petrochemistry and biotechnology relevant products Eur. J. Phys. 34 S139-59 [7] Krabbe A, Mehlert D, Röser H-P and Scorza C 2013 SOFIA, an airborne observatory for infrared astronomy

  10. Integrated Model of Multiple Kernel Learning and Differential Evolution for EUR/USD Trading

    PubMed Central

    Deng, Shangkun; Sakurai, Akito

    2014-01-01

    Currency trading is an important area for individual investors, government policy decisions, and organization investments. In this study, we propose a hybrid approach referred to as MKL-DE, which combines multiple kernel learning (MKL) with differential evolution (DE) for trading a currency pair. MKL is used to learn a model that predicts changes in the target currency pair, whereas DE is used to generate the buy and sell signals for the target currency pair based on the relative strength index (RSI), while it is also combined with MKL as a trading signal. The new hybrid implementation is applied to EUR/USD trading, which is the most traded foreign exchange (FX) currency pair. MKL is essential for utilizing information from multiple information sources and DE is essential for formulating a trading rule based on a mixture of discrete structures and continuous parameters. Initially, the prediction model optimized by MKL predicts the returns based on a technical indicator called the moving average convergence and divergence. Next, a combined trading signal is optimized by DE using the inputs from the prediction model and technical indicator RSI obtained from multiple timeframes. The experimental results showed that trading using the prediction learned by MKL yielded consistent profits. PMID:25097891

  11. Integrated model of multiple kernel learning and differential evolution for EUR/USD trading.

    PubMed

    Deng, Shangkun; Sakurai, Akito

    2014-01-01

    Currency trading is an important area for individual investors, government policy decisions, and organization investments. In this study, we propose a hybrid approach referred to as MKL-DE, which combines multiple kernel learning (MKL) with differential evolution (DE) for trading a currency pair. MKL is used to learn a model that predicts changes in the target currency pair, whereas DE is used to generate the buy and sell signals for the target currency pair based on the relative strength index (RSI), while it is also combined with MKL as a trading signal. The new hybrid implementation is applied to EUR/USD trading, which is the most traded foreign exchange (FX) currency pair. MKL is essential for utilizing information from multiple information sources and DE is essential for formulating a trading rule based on a mixture of discrete structures and continuous parameters. Initially, the prediction model optimized by MKL predicts the returns based on a technical indicator called the moving average convergence and divergence. Next, a combined trading signal is optimized by DE using the inputs from the prediction model and technical indicator RSI obtained from multiple timeframes. The experimental results showed that trading using the prediction learned by MKL yielded consistent profits.

  12. Precision measurement of ^23Al beta-decay

    NASA Astrophysics Data System (ADS)

    Zhai, Yongjun; Iacob, V. E.; Hardy, J. C.; Al-Abdullah, T.; Banu, A.; Fu, C.; Golovko, V. V.; McCleskey, M.; Nica, N.; Park, H. I.; Tabacaru, G.; Tribble, R. E.; Trache, L.

    2007-10-01

    The beta-decay of ^23Al (See [1]) was re-measured with higher statistics and better accuracy at Texas A&M University. Using MARS we produced and separated pure ^23Al at 4000 pps, with a 48 MeV/u ^24Mg beam via the ^24Mg (p, 2n)^ 23Al reaction on a H2 cryogenic target. New β and β-γ coincidence measurements were made with a scintillator, an HPGe detector with BGO shielding and the fast tape transport system. The BGO Compton shield very much improved the quality of the γ spectra around the transition from the IAS state at 7803 keV. From the measured β singles and β-γ coincidence decay spectra we obtained an improved β-decay scheme and a more precise lifetime: t=447(4) ms. We use the method of detailed balance to obtain absolute β-branching ratios and absolute logft values for transitions to final states in ^23Mg. For this method, precise efficiency calibration of the HPGe detector up to about 8 MeV is needed. We extended our previous efficiency calibration to the range Eγ=3.5-8 MeV using the β-decay of ^24Al. [1] V.E. Iacob, Y. Zhai et al., Phys. Rev. C 74, 045810 (2006).

  13. Ionization of Atoms by Slow Heavy Particles, Including Dark Matter.

    PubMed

    Roberts, B M; Flambaum, V V; Gribakin, G F

    2016-01-15

    Atoms and molecules can become ionized during the scattering of a slow, heavy particle off a bound electron. Such an interaction involving leptophilic weakly interacting massive particles (WIMPs) is a promising possible explanation for the anomalous 9σ annual modulation in the DAMA dark matter direct detection experiment [R. Bernabei et al., Eur. Phys. J. C 73, 2648 (2013)]. We demonstrate the applicability of the Born approximation for such an interaction by showing its equivalence to the semiclassical adiabatic treatment of atomic ionization by slow-moving WIMPs. Conventional wisdom has it that the ionization probability for such a process should be exponentially small. We show, however, that due to nonanalytic, cusplike behavior of Coulomb functions close to the nucleus this suppression is removed, leading to an effective atomic structure enhancement. We also show that electron relativistic effects actually give the dominant contribution to such a process, enhancing the differential cross section by up to 1000 times.

  14. Pre-Town Meeting on spin physics at an Electron-Ion Collider

    DOE PAGES

    Aschenauer, Elke-Caroline; Balitsky, Ian; Bland, Leslie; ...

    2017-04-14

    A polarized ep/eA collider (Electron-Ion Collider, or EIC), with polarized proton and light-ion beams and unpolarized heavy-ion beams with a variable center-of-mass energy √s ~ 20 to ~ 100 GeV (upgradable to ~ 150 GeV) and a luminosity up to ~10 34 cm -2s -1, would be uniquely suited to address several outstanding questions of Quantum Chromodynamics, and thereby lead to new qualitative and quantitative information on the microscopic structure of hadrons and nuclei. During this meeting at Jefferson Lab we addressed recent theoretical and experimental developments in the spin and the three-dimensional structure of the nucleon (sea quark andmore » gluon spatial distributions, orbital motion, polarization, and their correlations). Finally, this mini-paper contains a short update on progress in these areas since the EIC White paper (A. Accardi et al., Eur. Phys. J. A 52, 268 (2016)).« less

  15. Structure of V{sub 2}AlC studied by theory and experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schneider, Jochen M.; Mertens, Raphael; Music, Denis

    2006-01-01

    We have studied V{sub 2}AlC (space group P6{sub 3}/mmc, prototype Cr{sub 2}AlC) by ab initio calculations. The density of states (DOS) of V{sub 2}AlC for antiferromagnetic, ferromagnetic, and paramagnetic configurations have been discussed. According to the analysis of DOS and cohesive energy, no significant stability differences between spin-polarized and non-spin-polarized configurations were found. Based on the partial DOS analysis, V{sub 2}AlC can be classified as a strongly coupled nanolaminate according to our previous work [Z. Sun, D. Music, R. Ahuja, S. Li, and J. M. Schneider, Phys. Rev. B 70, 092102 (2004)]. Furthermore, this phase has been synthesized in themore » form of thin films by magnetron sputtering. The equilibrium volume, determined by x-ray diffraction, is in good agreement with the theoretical data, implying that ab initio calculations provide an accurate description of V{sub 2}AlC.« less

  16. Current Collapse Induced in AlGaN/GaN High-Electron-Mobility Transistors by Bias Stress

    DTIC Science & Technology

    2003-08-25

    structure where the traps causing current collapse can be passivated by forming H-defect complexes. Hierro et al.7 have shown, for example, that deep...Lett. 75, 4016 ~1999!. 7 A. Hierro , S. A. Ringel, M. Hansen, J. S. Speck, U. K. Mishra, and S. P. DenBaars, Appl. Phys. Lett. 77, 1499 ~2000!. 8 S. J

  17. Comment on 'General nonlocality in quantum fields'[J. Math. Phys. 49, 033513 (2008)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang Haijun

    2010-05-15

    In a recent paper [H.-J. Wang, J. Math. Phys. 49, 033513 (2008)] a complex-geometry model was proposed to interpret the interaction of electromagnetism and the interaction between quarks while the nonlocal effects are involved. In that theoretical frame, from the metric matrix one can obtain a determinant-form condition to describe qualitatively the typical characteristics for the aforementioned interactions. In this comment we attempt to extend this kind of qualitative description to weak interaction by finding out an appropriate metric tensor for it.

  18. NMR parameters in column 13 metal fluoride compounds (AlF₃, GaF₃, InF₃ and TlF) from first principle calculations.

    PubMed

    Sadoc, Aymeric; Biswal, Mamata; Body, Monique; Legein, Christophe; Boucher, Florent; Massiot, Dominique; Fayon, Franck

    2014-01-01

    The relationship between the experimental (19)F isotropic chemical shift and the (19)F isotropic shielding calculated using the gauge including projector augmented-wave (GIPAW) method with PBE functional is investigated in the case of GaF3, InF3, TlF and several AlF3 polymorphs. It is shown that the linear correlation between experimental and DFT-PBE calculated values previously established on alkali, alkaline earth and rare earth of column 3 basic fluorides (Sadoc et al., Phys. Chem. Chem. Phys. 13 (2011) 18539-18550) remains valid in the case of column 13 metal fluorides, indicating that it allows predicting (19)F solid state NMR spectra of a broad range of crystalline fluorides with a relatively good accuracy. For the isostructural α-AlF3, GaF3 and InF3 phases, PBE-DFT geometry optimization leads to noticeably overbended M-F-M bond angles and underestimated (27)Al, (71)Ga and (115)In calculated quadrupolar coupling constants. For the studied compounds, whose structures are built of corner shared MF6 octahedra, it is shown that the electric field gradient (EFG) tensor at the cationic sites is not related to distortions of the octahedral units, in contrast to what previously observed for isolated AlF6 octahedra in fluoroaluminates. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Components of a standardised olive leaf dry extract (Ph. Eur.) promote hypothiocyanite production by lactoperoxidase.

    PubMed

    Flemmig, Jörg; Rusch, Dorothea; Czerwińska, Monika Ewa; Rauwald, Hans-Wilhelm; Arnhold, Jürgen

    2014-05-01

    We investigated in vitro the ability of a standardised olive leaf dry extract (Ph. Eur.) (OLE) as well as of its single components to circumvent the hydrogen peroxide-induced inhibition of the hypothiocyanite-producing activity of lactoperoxidase (LPO). The rate of hypothiocyanite (⁻OSCN) formation by LPO was quantified by spectrophotometric detection of the oxidation of 5-thio-2-nitrobenzoic acid (TNB). By using excess hydrogen peroxide, we forced the accumulation of inactive enzymatic intermediates which are unable to promote the two-electronic oxidation of thiocyanate. Both OLE and certain extract components showed a strong LPO-reactivating effect. Thereby an o-hydroxyphenolic moiety emerged to be essential for a good reactivity with the inactive LPO redox states. This basic moiety is found in the main OLE components oleuropein, oleacein, hydroxytyrosol, caffeic acid as well as in different other constituents including the OLE flavone luteolin. As LPO is a key player in the humoral immune response, these results propose a new mode of action regarding the well-known bacteriostatic and anti-inflammatory properties of the leaf extract of Olea europaea L. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Corrigendum to ;Wounded quarks and diquarks in heavy ion collisions; [Phys. Lett. B 649 (2007) 263

    NASA Astrophysics Data System (ADS)

    Bialas, A.; Bzdak, A.

    2017-10-01

    Numerical result in Eq. (15), σqq /σNN = 1.147 - 1.148, as given in [Phys. Lett. B 649 (2007) 263] should be corrected to σqq /σNN = 0.147 - 0.148. The conclusions of the original paper remain unchanged. We thank Partha Pratim Bhaduri for pointing out this typo.

  1. Addendum: New approach to the resummation of logarithms in Higgs-boson decays to a vector quarkonium plus a photon [Phys. Rev. D 95, 054018 (2017)

    DOE PAGES

    Bodwin, Geoffrey T.; Chung, Hee Sok; Ee, June-Haak; ...

    2017-12-20

    In this addendum to Phys. Rev. D 95, 054018 (2017) we recompute the rates for the decays of the Higgs boson to a vector quarkonium plus a photon, where the vector quarkonium is J/psi, Upsilon(1S) Upsilon(2S). We correct an error in the Abel-Pad'e summation formula that was used to carry out the evolution of the quarkonium light-cone distribution amplitude in Phys. Rev. D 95, 054018 (2017). We also correct an error in the scale of quarkonium wave function at the origin in Phys. Rev. D 95, 054018 (2017) and introduce several additional refinements in the calculation.

  2. Addendum: New approach to the resummation of logarithms in Higgs-boson decays to a vector quarkonium plus a photon [Phys. Rev. D 95, 054018 (2017)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bodwin, Geoffrey T.; Chung, Hee Sok; Ee, June-Haak

    In this addendum to Phys. Rev. D 95, 054018 (2017) we recompute the rates for the decays of the Higgs boson to a vector quarkonium plus a photon, where the vector quarkonium is J/psi, Upsilon(1S) Upsilon(2S). We correct an error in the Abel-Pad'e summation formula that was used to carry out the evolution of the quarkonium light-cone distribution amplitude in Phys. Rev. D 95, 054018 (2017). We also correct an error in the scale of quarkonium wave function at the origin in Phys. Rev. D 95, 054018 (2017) and introduce several additional refinements in the calculation.

  3. Internal quantum efficiency in yellow-amber light emitting AlGaN-InGaN-GaN heterostructures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ngo, Thi Huong; Gil, Bernard; Valvin, Pierre

    2015-09-21

    We determine the internal quantum efficiency of strain-balanced AlGaN-InGaN-GaN hetero-structures designed for yellow-amber light emission, by using a recent model based on the kinetics of the photoluminescence decay initiated by Iwata et al. [J. Appl. Phys. 117, 075701 (2015)]. Our results indicate that low temperature internal quantum efficiencies sit in the 50% range and we measure that adding an AlGaN layer increases the internal quantum efficiency from 50% up to 57% with respect to the GaN-InGaN case. More dramatic, it almost doubles from 2.5% up to 4.3% at room temperature.

  4. Three-electron spin qubits

    NASA Astrophysics Data System (ADS)

    Russ, Maximilian; Burkard, Guido

    2017-10-01

    The goal of this article is to review the progress of three-electron spin qubits from their inception to the state of the art. We direct the main focus towards the exchange-only qubit (Bacon et al 2000 Phys. Rev. Lett. 85 1758-61, DiVincenzo et al 2000 Nature 408 339) and its derived versions, e.g. the resonant exchange (RX) qubit, but we also discuss other qubit implementations using three electron spins. For each three-spin qubit we describe the qubit model, the envisioned physical realization, the implementations of single-qubit operations, as well as the read-out and initialization schemes. Two-qubit gates and decoherence properties are discussed for the RX qubit and the exchange-only qubit, thereby completing the list of requirements for quantum computation for a viable candidate qubit implementation. We start by describing the full system of three electrons in a triple quantum dot, then discuss the charge-stability diagram, restricting ourselves to the relevant subsystem, introduce the qubit states, and discuss important transitions to other charge states (Russ et al 2016 Phys. Rev. B 94 165411). Introducing the various qubit implementations, we begin with the exchange-only qubit (DiVincenzo et al 2000 Nature 408 339, Laird et al 2010 Phys. Rev. B 82 075403), followed by the RX qubit (Medford et al 2013 Phys. Rev. Lett. 111 050501, Taylor et al 2013 Phys. Rev. Lett. 111 050502), the spin-charge qubit (Kyriakidis and Burkard 2007 Phys. Rev. B 75 115324), and the hybrid qubit (Shi et al 2012 Phys. Rev. Lett. 108 140503, Koh et al 2012 Phys. Rev. Lett. 109 250503, Cao et al 2016 Phys. Rev. Lett. 116 086801, Thorgrimsson et al 2016 arXiv:1611.04945). The main focus will be on the exchange-only qubit and its modification, the RX qubit, whose single-qubit operations are realized by driving the qubit at its resonant frequency in the microwave range similar to electron spin resonance. Two different types of two-qubit operations are presented for the exchange

  5. What the multiline signal (MLS) simulation data with average of weighted computations reveal about the Mn hyperfine interactions and oxidation states of the manganese cluster in OEC?

    NASA Astrophysics Data System (ADS)

    Baituti, Bernard

    2017-11-01

    Understanding the structure of oxygen evolving complex (OEC) fully still remains a challenge. Lately computational chemistry with the data from more detailed X-ray diffraction (XRD) OEC structure, has been used extensively in exploring the mechanisms of water oxidation in the OEC (Gatt et al., J. Photochem. Photobiol. B 104(1-2), 80-93 2011). Knowledge of the oxidation states is very crucial for understanding the core principles of catalysis by photosystem II (PSII) and catalytic mechanism of OEC. The present study involves simulation studies of the X-band continuous wave electron-magnetic resonance (CW-EPR) generated S 2 state signals, to investigate whether the data is in agreement with the four manganese ions in the OEC, being organised as a `3 + 1' (trimer plus one) model (Gatt et al., Angew. Chem. Int. Ed. 51, 12025-12028 2012; Petrie et al., Chem. A Eur. J. 21, 6780-6792 2015; Terrett et al., Chem. Commun. (Camb.) 50, 8-11 2014) or `dimer of dimers' model (Terrett et al. 2016). The question that still remains is how much does each Mn ion contribute to the " g2multiline" signal through its hyperfine interactions in OEC also to differentiate between the `high oxidation state (HOS)' and `low oxidation state (LOS)' paradigms? This is revealed in part by the structure of multiline (ML) signal studied in this project. Two possibilities have been proposed for the redox levels of the Mn ions within the catalytic cluster, the so called `HOS' and `LOS' paradigms (Gatt et al., J. Photochem. Photobiol. B 104(1-2), 80-93 2011). The method of data analysis involves numerical simulations of the experimental spectra on relevant models of the OEC cluster. The simulations of the X-band CW-EPR multiline spectra, revealed three manganese ions having hyperfine couplings with large anisotropy. These are most likely Mn III centres and these clearly support the `LOS' OEC paradigm model, with a mean oxidation of 3.25 in the S2 state. This is consistent with the earlier data by Jin et

  6. Erratum: Binary neutron stars with arbitrary spins in numerical relativity [Phys. Rev. D 92, 124012 (2015)

    NASA Astrophysics Data System (ADS)

    Tacik, Nick; Foucart, Francois; Pfeiffer, Harald P.; Haas, Roland; Ossokine, Serguei; Kaplan, Jeff; Muhlberger, Curran; Duez, Matt D.; Kidder, Lawrence E.; Scheel, Mark A.; Szilágyi, Béla

    2016-08-01

    The code used in [Phys. Rev. D 92, 124012 (2015)] erroneously computed the enthalpy at the center of the neutron stars. Upon correcting this error, density oscillations in evolutions of rotating neutron stars are significantly reduced (from ˜20 % to ˜0.5 % ). Furthermore, it is possible to construct neutron stars with faster rotation rates.

  7. Determination of {pi}{sup {+-}} meson polarizabilities from the {gamma}{gamma}{yields}{pi}{sup +}{pi}{sup -} process

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fil'kov, L.V.; Kashevarov, V.L.

    2006-03-15

    A fit of the experimental data to the total cross section of the process {gamma}{gamma}{yields}{pi}{sup +}{pi}{sup -} in the energy region from threshold to 2500 MeV has been carried out using dispersion relations with subtractions for the invariant amplitudes, where the dipole and the quadrupole polarizabilities of the charged pion are free parameters. As a result, the sum and the difference of the electric and magnetic dipole and quadrupole polarizabilities of the charged pion have been found: ({alpha}{sub 1}+{beta}{sub 1}){sub {pi}{sup {+-}}}=(0.18{sub -0.02}{sup +0.11})x10{sup -4} fm{sup 3},({alpha}{sub 1}-{beta}{sub 1}){sub {pi}{sup {+-}}}=(13.0{sub -1.9}{sup +2.6})x10{sup -4} fm{sup 3},({alpha}{sub 2}+{beta}{sub 2}){sub {pi}{sup {+-}}}=(0.133{+-}0.015)x10{supmore » -4} fm{sup 5},({alpha}{sub 2}-{beta}{sub 2}){sub {pi}{sup {+-}}}=(25.0{sub -0.3}{sup +0.8})x10{sup -4} fm{sup 5}. These values agree with the dispersion sum rule predictions. The value found for the difference of the dipole polarizabilities is consistent with the results obtained from scattering of high energy {pi}{sup -} mesons off the Coulomb field of heavy nuclei [Yu. M. Antipov et al., Phys. Lett. B121, 445 (1983)] and from radiative {pi}{sup +} photoproduction from the proton at MAMI [J. Ahrens et al., Eur. Phys. J. A 23, 113 (2005)], whereas it is at variance with the recent calculations in the framework of chiral perturbation theory.« less

  8. Frictional Torque on a Rotating Disc

    DTIC Science & Technology

    2012-01-01

    Tracker Eur. J. Phys. 33 615–22 [2] Alam J, Hassan H, Shamim S , Mahmood W and Anwar M S 2011 Precise measurement of velocity dependent friction in...on a rotating disc 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT...NUMBER 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) US Naval Academy,Physics Department,Annapolis,MD,21402-1363 8. PERFORMING ORGANIZATION

  9. EurOOHnet-the European research network for out-of-hours primary health care.

    PubMed

    Huibers, Linda; Philips, Hilde; Giesen, Paul; Remmen, Roy; Christensen, Morten Bondo; Bondevik, Gunnar Tschudi

    2014-09-01

    European countries face similar challenges in the provision of health care. Demographic factors like ageing, population growth, changing patient behaviour, and lack of work force lead to increasing demands, costs, and overcrowding of out-of-hours (OOH) care (i.e. primary care services, emergency departments (EDs), and ambulance services). These developments strain services and imply safety risks. In the last few decades, countries have been re-organizing their OOH primary health care services. AIM AND SCOPE OF THE NETWORK: We established a European research network for out-of-hours primary health care (EurOOHnet), which aims to transfer knowledge, share experiences, and conduct research. Combining research competencies and integrating results can generate a profound information flow to European researchers and decision makers in health policy, contributing towards feasible and high-quality OOH care. It also contributes to a more comparable performance level within European regions. CONDUCTED RESEARCH PROJECTS: The European research network aims to conduct mutual research projects. At present, three projects have been accomplished, among others concerning the diagnostic scope in OOH primary care services and guideline adherence for diagnosis and treatment of cystitis in OOH primary care. Future areas of research will be organizational models for OOH care; appropriate use of the OOH services; quality of telephone triage; quality of medical care; patient safety issues; use of auxiliary personnel; collaboration with EDs and ambulance care; and the role of GPs in OOH care.

  10. Evidence from x-ray and neutron powder diffraction patterns that the so-called icosahedral and decagonal quasicrystals of MnAl(6) and other alloys are twinned cubic crystals.

    PubMed

    Pauling, L

    1987-06-01

    It is shown that the x-ray powder diffraction patterns of rapidly quenched MnAl(6) and Mg(32)(Al,Zn)(49) and the neutron powder diffraction pattern of MnAl(6) are compatible with the proposed 820-atom primitive cubic structure [Pauling, L. (1987) Phys. Rev. Lett. 58, 365-368]. The values found for the edge of the unit cube are 23.365 A (x-ray) and 23.416 A (neutron) for MnAl(6) and 24.313 A (x-ray) for Mg(32)(Al,Zn)(49).

  11. Evidence from x-ray and neutron powder diffraction patterns that the so-called icosahedral and decagonal quasicrystals of MnAl6 and other alloys are twinned cubic crystals

    PubMed Central

    Pauling, Linus

    1987-01-01

    It is shown that the x-ray powder diffraction patterns of rapidly quenched MnAl6 and Mg32(Al,Zn)49 and the neutron powder diffraction pattern of MnAl6 are compatible with the proposed 820-atom primitive cubic structure [Pauling, L. (1987) Phys. Rev. Lett. 58, 365-368]. The values found for the edge of the unit cube are 23.365 Å (x-ray) and 23.416 Å (neutron) for MnAl6 and 24.313 Å (x-ray) for Mg32(Al,Zn)49. PMID:16593841

  12. Excitonic recombination dynamics in non-polar GaN/AlGaN quantum wells

    NASA Astrophysics Data System (ADS)

    Rosales, D.; Gil, B.; Bretagnon, T.; Guizal, B.; Zhang, F.; Okur, S.; Monavarian, M.; Izyumskaya, N.; Avrutin, V.; Özgür, Ü.; Morkoç, H.; Leach, J. H.

    2014-02-01

    The optical properties of GaN/Al0.15Ga0.85N multiple quantum wells are examined in 8 K-300 K temperature range. Both polarized CW and time resolved temperature-dependent photoluminescence experiment are performed so that we can deduce the relative contributions of the non-radiative and radiative recombination processes. From the calculation of the proportion of the excitonic population having wave vector in the light cone, we can deduce the variation of the radiative decay time with temperature. We find part of the excitonic population to be localized in concert with the report of Corfdir et al. (Jpn. J. Appl. Phys., Part 2 52, 08JC01 (2013)) in case of a-plane quantum wells.

  13. Comment on ``On the Crooks fluctuation theorem and the Jarzynski equality'' [J. Chem. Phys. 129, 091101 (2008)

    NASA Astrophysics Data System (ADS)

    Adib, Artur B.

    2009-06-01

    It has recently been argued that a self-consistency condition involving the Jarzynski equality (JE) and the Crooks fluctuation theorem (CFT) is violated for a simple Brownian process [L. Y. Chen, J. Chem. Phys.129, 091101 (2008)]. This note adopts the definitions in the original formulation of the JE and CFT and demonstrates the contrary.

  14. Global two-fluid turbulence simulations of L-H transitions and edge localized mode dynamics in the COMPASS-D tokamak

    NASA Astrophysics Data System (ADS)

    Thyagaraja, A.; Valovič, M.; Knight, P. J.

    2010-04-01

    It is shown that the transition from L-mode to H-mode regimes in tokamaks can be reproduced using a two-fluid, fully electromagnetic, plasma model when a suitable particle sink is added at the edge. Such a model is implemented in the CUTIE code [A. Thyagaraja et al., Eur. J. Mech. B/Fluids 23, 475 (2004)] and is illustrated on plasma parameters that mimic those in the COMPASS-D tokamak with electron cyclotron resonance heating [Fielding et al., Plasma Phys. Contr. Fusion 42, A191 (2000)]. In particular, it is shown that holding the heating power, current, and magnetic field constant and increasing the fuelling rate to raise the plasma density leads spontaneously to the formation of an edge transport barrier (ETB) which occurs going from low to higher density experimentally. In the following quiescent period in which the stored energy of the plasma rises linearly with time, a dynamical transition occurs in the simulation with the appearance of features resembling strong edge localized modes. The simulation qualitatively reproduces many features observed in the experiment. Its relative robustness suggests that some, at least of the observed characteristics of ETBs and L-H transitions, can be captured in the global electromagnetic turbulence model.

  15. Comment on 'Power loss in open cavity diodes and a modified Child-Langmuir law' [Phys. Plasmas 12, 093102 (2005)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Swanekamp, S. B.; Ottinger, P. F.

    In this Comment, it is shown that no modification of the Child-Langmuir law [Phys. Rev.32, 492 (1911); Phys. Rev. 2, 450 (1913)] is necessary to treat the space-charge-limited flow from a diode with an open boundary as reported in Phys. Plasmas 12, 093102 (2005). The open boundary condition in their simulations can be represented by a voltage source and a resistor whose value is the vacuum-wave impedance of the opening. The diode can be represented as a variable resistor whose value depends on the voltage drop across the diode (as measured by the line integral of E across the diodemore » gap). This is a simple voltage-divider circuit whose analysis shows that the real diode voltage drops as the vacuum-wave impedance increases. Furthermore, it is shown that in equilibrium, the voltage drop between the anode and cathode is independent of the path chosen for the line integral of the electric field so that E=-{nabla}{phi} is valid. In this case, the equations of electrostatics are applicable. This clearly demonstrates that the electric field is electrostatic and static fields DO NOT RADIATE. It is shown that the diode voltage drops as the vacuum wave impedance increases and the current drops according to the Child-Langmuir law. Therefore, the observed drop in circuit current can be explained by a real drop in voltage across the diode and not an effective drop as claimed by the authors.« less

  16. Microeconomics of the ideal gas like market models

    NASA Astrophysics Data System (ADS)

    Chakrabarti, Anindya S.; Chakrabarti, Bikas K.

    2009-10-01

    We develop a framework based on microeconomic theory from which the ideal gas like market models can be addressed. A kinetic exchange model based on that framework is proposed and its distributional features have been studied by considering its moments. Next, we derive the moments of the CC model (Eur. Phys. J. B 17 (2000) 167) as well. Some precise solutions are obtained which conform with the solutions obtained earlier. Finally, an output market is introduced with global price determination in the model with some necessary modifications.

  17. Collision of a Ball with a Barbell and Related Impulse Problems

    DTIC Science & Technology

    2007-04-24

    dynamics Many introductory physics books discuss the problem of a ball striking a barbell (or more generally a stick with some specified mass distribution...904 [9] Serway R A and Jewett J W 2008 Physics for Scientists and Engineers 7th edn (Belmont, CA: Thomson) at press Example 11.9 [10] Doménech A and...IOP PUBLISHING EUROPEAN JOURNAL OF PHYSICS Eur. J. Phys. 28 (2007) 563–568 doi:10.1088/0143-0807/28/3/018 Collision of a ball with a barbell and

  18. Epitaxial Growths of m-Plane AlGaN/GaN and AlInN/GaN Heterostructures Applicable for Normally-Off Mode High Power Field Effect Transistors on Freestanding GaN Substrates

    DTIC Science & Technology

    2011-08-17

    cathodoluminescence (CL), and Hall effect measurement. We will disclose how structural and point defects affect the internal quantum efficiency. We have a complete...18. S. F. Chichibu, A. Uedono, T. Onuma, S. P. DenBaars, U. K. Mishra, J. S. Speck, and S. Nakamura, “Impact of Point Defects on the Luminescence...A. Uedono, “Major impacts of point defects and impurities on the carrier recombination dynamics in AlN,” Appl. Phys. Lett. 97(20), 201904 (2010

  19. High-Precision Differential Predictions for Top-Quark Pairs at the LHC

    NASA Astrophysics Data System (ADS)

    Czakon, Michal; Heymes, David; Mitov, Alexander

    2016-02-01

    We present the first complete next-to-next-to-leading order (NNLO) QCD predictions for differential distributions in the top-quark pair production process at the LHC. Our results are derived from a fully differential partonic Monte Carlo calculation with stable top quarks which involves no approximations beyond the fixed-order truncation of the perturbation series. The NNLO corrections improve the agreement between existing LHC measurements [V. Khachatryan et al. (CMS Collaboration), Eur. Phys. J. C 75, 542 (2015)] and standard model predictions for the top-quark transverse momentum distribution, thus helping alleviate one long-standing discrepancy. The shape of the top-quark pair invariant mass distribution turns out to be stable with respect to radiative corrections beyond NLO which increases the value of this observable as a place to search for physics beyond the standard model. The results presented here provide essential input for parton distribution function fits, implementation of higher-order effects in Monte Carlo generators, as well as top-quark mass and strong coupling determination.

  20. High-Precision Differential Predictions for Top-Quark Pairs at the LHC.

    PubMed

    Czakon, Michal; Heymes, David; Mitov, Alexander

    2016-02-26

    We present the first complete next-to-next-to-leading order (NNLO) QCD predictions for differential distributions in the top-quark pair production process at the LHC. Our results are derived from a fully differential partonic Monte Carlo calculation with stable top quarks which involves no approximations beyond the fixed-order truncation of the perturbation series. The NNLO corrections improve the agreement between existing LHC measurements [V. Khachatryan et al. (CMS Collaboration), Eur. Phys. J. C 75, 542 (2015)] and standard model predictions for the top-quark transverse momentum distribution, thus helping alleviate one long-standing discrepancy. The shape of the top-quark pair invariant mass distribution turns out to be stable with respect to radiative corrections beyond NLO which increases the value of this observable as a place to search for physics beyond the standard model. The results presented here provide essential input for parton distribution function fits, implementation of higher-order effects in Monte Carlo generators, as well as top-quark mass and strong coupling determination.

  1. On the emergence of an ‘intention field’ for socially cohesive agents

    NASA Astrophysics Data System (ADS)

    Bouchaud, Jean-Philippe; Borghesi, Christian; Jensen, Pablo

    2014-03-01

    We argue that when a social convergence mechanism exists and is strong enough, one should expect the emergence of a well-defined ‘field’, i.e. a slowly evolving, local quantity around which individual attributes fluctuate in a finite range. This condensation phenomenon is well illustrated by the Deffuant-Weisbuch opinion model for which we provide a natural extension to allow for spatial heterogeneities. We show analytically and numerically that the resulting dynamics of the emergent field is a noisy diffusion equation that has a slow dynamics. This random diffusion equation reproduces the long-ranged, logarithmic decrease of the correlation of spatial voting patterns empirically found in Borghesi and Bouchaud (2010 Eur. Phys. J. B 75 395) and Borghesi et al (2012 PLoS One 7 e36289). Interestingly enough, we find that when the social cohesion mechanism becomes too weak, cultural cohesion breaks down completely, in the sense that the distribution of intentions/opinions becomes infinitely broad. No emerging field exists in this case. All these analytical findings are confirmed by numerical simulations of an agent-based model.

  2. Top-forms of leading singularities in nonplanar multi-loop amplitudes

    NASA Astrophysics Data System (ADS)

    Chen, Baoyi; Chen, Gang; Cheung, Yeuk-Kwan E.; Xie, Ruofei; Xin, Yuan

    2018-02-01

    The on-shell diagram is a very important tool in studying scattering amplitudes. In this paper we discuss the on-shell diagrams without external BCFW bridges. We introduce an extra step of adding an auxiliary external momentum line. Then we can decompose the on-shell diagrams by removing external BCFW bridges to a planar diagram whose top-form is well known now. The top-form of the on-shell diagram with the auxiliary line can be obtained by adding the BCFW bridges in an inverse order as discussed in our former paper (Chen et al. in Eur Phys J C 77(2):80 2017). To get the top-form of the original diagram, the soft limit of the auxiliary line is needed. We obtain the evolution rule for the Grassmannian integral and the geometry constraint in the soft limit. This completes the top-form description of leading singularities in nonplanar scattering amplitudes of N=4 Super Yang-Mills (SYM), which is valid for arbitrary higher-loops and beyond the Maximally-Helicity-Violation (MHV) amplitudes.

  3. Why ghosts don’t touch: a tale of two adventurers falling one after another into a black hole

    NASA Astrophysics Data System (ADS)

    Kassner, Klaus

    2017-01-01

    The case for the utility of Kruskal-Szekeres coordinates in the classroom made by Augousti et al in this journal (2012 Eur. J. Phys. 33 1-11) is strengthened by extending their discussion beyond the event horizon of the black hole. Observations made by two adventurers following one another into a Schwarzschild black hole are examined in terms of these nonsingular coordinates. Two scenarios are considered, the first corresponding to one observer following the other closely, the second to a significant distance between the two of them, precluding the existence of a common inertial system. In particular, the concepts of distance and temporal separation near the horizon and the redshift of the first infaller's image as seen by the second are investigated. The results show that the notion of ‘touching ghosts’ does not correspond to the local physics of two observers falling into a black hole. The story line is interesting enough and the mathematical details are sufficiently simple to use the example in a general relativity course, even at the undergraduate level.

  4. A study of the Boltzmann and Gibbs entropies in the context of a stochastic toy model

    NASA Astrophysics Data System (ADS)

    Malgieri, Massimiliano; Onorato, Pasquale; De Ambrosis, Anna

    2018-05-01

    In this article we reconsider a stochastic toy model of thermal contact, first introduced in Onorato et al (2017 Eur. J. Phys. 38 045102), showing its educational potential for clarifying some current issues in the foundations of thermodynamics. The toy model can be realized in practice using dice and coins, and can be seen as representing thermal coupling of two subsystems with energy bounded from above. The system is used as a playground for studying the different behaviours of the Boltzmann and Gibbs temperatures and entropies in the approach to steady state. The process that models thermal contact between the two subsystems can be proved to be an ergodic, reversible Markov chain; thus the dynamics produces an equilibrium distribution in which the weight of each state is proportional to its multiplicity in terms of microstates. Each one of the two subsystems, taken separately, is formally equivalent to an Ising spin system in the non-interacting limit. The model is intended for educational purposes, and the level of readership of the article is aimed at advanced undergraduates.

  5. A charged anisotropic well-behaved Adler-Finch-Skea solution satisfying Karmarkar condition

    NASA Astrophysics Data System (ADS)

    Bhar, Piyali; Singh, Ksh. Newton; Rahaman, Farook; Pant, Neeraj; Banerjee, Sumita

    In the present paper, we discover a new well-behaved charged anisotropic solution of Einstein-Maxwell’s field equations. We ansatz the metric potential g00 of the form given by Maurya et al. (Eur. Phys. J. C 76(12) (2016) 693) with n = 2. In their paper, it is mentioned that for n = 2, the solution is not well-behaved for neutral configuration as the speed of sound is nondecreasing radially outward. However, the solution can represent a physically possible configuration with the inclusion of some net electric charge, i.e. the solution can become a well-behaved solution with decreasing sound speed radially outward for a charged configuration. Due to the inclusion of electric charge, the solution leads to a very stiff equation-of-state (EoS) with the velocity of sound at the center vr02 = 0.819, vt02 = 0.923 and the compactness parameter u = 0.823 is close to the Buchdahl limit 0.889. This stiff EoS support a compact star configuration of mass 5.418M⊙ and radius of 10.1km.

  6. PREFACE: International Symposium "Nanoscience and Quantum Physics 2011" (nanoPHYS'11)

    NASA Astrophysics Data System (ADS)

    Saito, Susumu; Tanaka, Hidekazu; Nakamura, Takashi; Nakamura, Masaaki

    2011-07-01

    Quantum physics has developed modern views of nature for more than a century. In addition to this traditional role, quantum physics has acquired new significance in the 21st century as the field responsible for driving and supporting nanoscience research, which will have even greater importance in the future because nanoscience will be the academic foundation for new technologies. The Department of Physics, Tokyo Institute of Technology, are now conducting a "Nanoscience and Quantum Physics" project (Physics G-COE project) supported by the Global Center of Excellence Program of the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT) in order to promote research and education in these important academic fields. The International Symposium on Nanoscience and Quantum Physics, held in Tokyo, Japan, 26-28 January 2011 (nanoPHYS'11) was organized by the Physics G-COE project of the Tokyo Institute of Technology to provide an international forum for the open exchange of topical information and for stimulating discussion on novel concepts and future prospects of nanoscience and quantum physics. There were a total of 118 papers including 34 invited papers. This nanoPHYS'11 is the fourth symposium of this kind organized by the Tokyo Institute of Technology. Topics focused on in the symposium included: Category 1: Novel nanostructure (Nanowires, Nanotubes, Spin-related structure, etc) Category 2: Novel transport and electronic properties (Graphene, Topological insulators, Coherent control, etc) Category 3: Electronic and optical properties of nanostructure Category 4: Fundamental physics and new concept in quantum physics Category 5: Quantum Physics - Quantum information Category 6: Quantum Physics - Nuclear and Hadron Physics Category 7: Quantum Physics - Astrophysics, etc All the papers submitted to this issue have been reviewed under a stringent refereeing process, according to the normal rules of this Journal. The editors are grateful to all the

  7. Comment on ``A proposal for in vitro/GFR molecular erythema action spectrum'' [J. Appl. Phys. 104, 034701 (2008)

    NASA Astrophysics Data System (ADS)

    Björn, Lars Olof; de Gruijl, Frank R.; Diffey, Brian; Norval, Mary

    2009-06-01

    The recent article by de Souza, Lorenzini and Rizzatti [J. A. V. de Souza, F. Lorenzini, and M. R. Rizatti, J. Appl. Phys. 104, 034701 (2008)] in this journal needs corrections and clarifications on several points. The model used by them is not suitable for the study of erythema.

  8. Behavioral Analysis and Rescue of a Novel Cerebellar Mouse Model of Tuberous Sclerosis Complex

    DTIC Science & Technology

    2012-05-01

    and Silva; Lee et al.; Marui et al., 2004). Therefore, dysregulation of mTORC1 appears to be an important pathway leading to the autistic-phenotype...for understanding the role of cerebellar pathology in autism. Eur J Neurosci. 31, 544-55. Marui , T., et al., 2004. Association between the

  9. Response to “Comment on ‘Propagation of surface waves on a semi-bounded quantum magnetized collisional plasma’” [Phys. Plasmas 23, 044701 (2016)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Niknam, A. R., E-mail: a-niknam@sbu.ac.ir; Taheri Boroujeni, S.; Khorashadizadeh, S. M., E-mail: smkhorashadi@birjand.ac.ir

    2016-04-15

    We reply to the Comment of Moradi [Phys. Plasmas 23, 044701 (2016)] on our paper [Phys. Plasmas 20, 122106 (2013)]. It is shown that TM surface waves can propagate on the surface of a semi-bounded quantum magnetized collisional plasma in the Faraday configuration in the electrostatic limit. In addition, in the Faraday configuration, one can neglect the coupling of TM and TE modes in the two limiting cases of weak magnetic field (low cyclotron frequency) and strong magnetic field (high cyclotron frequency).

  10. Ab initio study of the temperature-dependent structural properties of Al(110)

    NASA Astrophysics Data System (ADS)

    Scharoch, Pawel

    2009-09-01

    Temperature-dependent structural properties of Al(110) surface have been studied ab initio employing the concepts of the potential-energy surface (PES) and the free-energy surface (FES), with the latter based on the harmonic approximation for lattice dynamics. Three effects have been identified as contributing to the temperature-dependent multilayer relaxation: the bulk-substrate thermal expansion, the effect of asymmetry of PESs, and the entropy-driven shift of the minima of FESs. Thanks to the proper choice of constraints for PESs and FESs, it was possible to find relative contribution of the three effects to variation with temperature of the first three interlayer distances. A very satisfactory agreement of the calculation results with experimental data has been obtained. Also, a reference of the theoretical data to the experimentally observed anisotropic surface melting has been noticed. A softening phonon mode has been identified which is responsible for both: the entropy-driven spectacular expansion of the second interlayer distance and the loss of the surface stability. The latter can be associated with the anisotropic surface melting. The methodology applied has been found to be complementary to previous theoretical works [N. Marzari, D. Vanderbilt, A. De Vita, and M. C. Payne, Phys. Rev. Lett. 82, 3296 (1999); S. Narasimhan, Phys. Rev. B 64, 125409 (2001)], by offering another point of view and additional insight into the relative contribution of different physical effects to the temperature-dependent structural phenomena in Al(110) surface.

  11. Systematization of α-decaying nuclei based on shell structures: The case of odd-even and odd-odd nuclei

    NASA Astrophysics Data System (ADS)

    Yarman, Tolga; Zaim, Nimet; Yarman, Ozan; Kholmetskii, Alexander; Arık, Metin

    In previous studies, we provided a novel systematization of α-decaying even-even and even-odd nuclei starting with the classically adopted mechanism [T. Yarman et al., Eur. Phys. J. A 52 (2016) 140; Eur. Phys. J. A 53 (2017) 4]. Knowing beforehand the measured decay half-life, we had taken as a parameter the probability of the α-particle as being first born in a unit period of time, within the parent nucleus before it is emitted out. We thence developed a scaffold based on shell properties of families composed of “alike nuclei”. Along the same line, we now present a systematization of odd-even (OE) as well as odd-odd (OO) nuclei. We apply our approach further to the investigation of the effect of pairing (e.g., the effect when the number of nucleons is increased by one neutron), and that of unpairing (e.g., the effect when the number of nucleons is decreased by one neutron); thus it becomes an even number for the case of odd-even nuclei (Case OE), and an odd number in the case of odd-odd nuclei (Case OO). For the first case (OE), we pick the exemplar set 161Re, 217Fr, 243Bk, 263Db; where we delineate by, respectively, Re, Fr, Bk, and Db all of the odd-even or odd-odd isotopes that neighbor the four mentioned odd-even isotopes on the proposed scaffold. We proceed in the same way for the second case (OO). Thus, we choose the exemplar set of odd-odd nuclei 172Ir, 218Ac, 244Es. We then gather all of the Ir, Ac, and Es odd-odd and odd-even isotopes that neighbor the three mentioned odd-odd isotopes on the proposed scaffold. We show that, in the former case, pairing, as expected, generally increases stability of the given nucleus; and in the latter case, unpairing works in just the opposite direction — i.e., it generally increases instability. We disclose “stability peaks” versus Z for both sets of nuclei, we tackle here. Furthermore, we present a study to highlight an outlook of “odd-A nuclei” at hand. Contrary to the general expectation, we unveil no

  12. Precision measurements with atom interferometry

    NASA Astrophysics Data System (ADS)

    Schubert, Christian; Abend, Sven; Schlippert, Dennis; Ertmer, Wolfgang; Rasel, Ernst M.

    2017-04-01

    Interferometry with matter waves enables precise measurements of rotations, accelerations, and differential accelerations [1-5]. This is exploited for determining fundamental constants [2], in fundamental science as e.g. testing the universality of free fall [3], and is applied for gravimetry [4], and gravity gradiometry [2,5]. At the Institut für Quantenoptik in Hannover, different approaches are pursued. A large scale device is designed and currently being set up to investigate the gain in precision for gravimetry, gradiometry, and fundamental tests on large baselines [6]. For field applications, a compact and transportable device is being developed. Its key feature is an atom chip source providing a collimated high flux of atoms which is expected to mitigate systematic uncertainties [7,8]. The atom chip technology and miniaturization benefits from microgravity experiments in the drop tower in Bremen and sounding rocket experiments [8,9] which act as pathfinders for space borne operation [10]. This contribution will report about our recent results. The presented work is supported by the CRC 1227 DQ-mat, the CRC 1128 geo-Q, the RTG 1729, the QUEST-LFS, and by the German Space Agency (DLR) with funds provided by the Federal Ministry of Economic Affairs and Energy (BMWi) due to an enactment of the German Bundestag under Grant No. DLR 50WM1552-1557. [1] P. Berg et al., Phys. Rev. Lett., 114, 063002, 2015; I. Dutta et al., Phys. Rev. Lett., 116, 183003, 2016. [2] J. B. Fixler et al., Science 315, 74 (2007); G. Rosi et al., Nature 510, 518, 2014. [3] D. Schlippert et al., Phys. Rev. Lett., 112, 203002, 2014. [4] A. Peters et al., Nature 400, 849, 1999; A. Louchet-Chauvet et al., New J. Phys. 13, 065026, 2011; C. Freier et al., J. of Phys.: Conf. Series 723, 012050, 2016. [5] J. M. McGuirk et al., Phys. Rev. A 65, 033608, 2002; P. Asenbaum et al., arXiv:1610.03832. [6] J. Hartwig et al., New J. Phys. 17, 035011, 2015. [7] H. Ahlers et al., Phys. Rev. Lett. 116, 173601

  13. Comment on "Density functional theory analysis of structural and electronic properties of orthorhombic perovskite CH3NH3PbI3" by Y. Wang et al., Phys. Chem. Chem. Phys., 2014, 16, 1424-1429.

    PubMed

    Even, J; Pedesseau, L; Katan, C

    2014-05-14

    Yun Wang et al. used density functional theory (DFT) to investigate the orthorhombic phase of CH3NH3PbI3, which has recently shown outstanding properties for photovoltaic applications. Whereas their analysis of ground state properties may represent a valuable contribution to understanding this class of materials, effects of spin-orbit coupling (SOC) cannot be overlooked as was shown in earlier studies. Moreover, their discussion on optical properties may be misleading for non-DFT-experts, and the nice agreement between experimental and calculated band gap is fortuitous, stemming from error cancellations between SOC and many-body effects. Lastly, Bader charges suggest potential problems during crystal structure optimization.

  14. Comments on "Adaptive resolution simulation in equilibrium and beyond" by H. Wang and A. Agarwal

    NASA Astrophysics Data System (ADS)

    Klein, R.

    2015-09-01

    Wang and Agarwal (Eur. Phys. J. Special Topics, this issue, 2015, doi: 10.1140/epjst/e2015-02411-2) discuss variants of Adaptive Resolution Molecular Dynamics Simulations (AdResS), and their applications. Here we comment on their report, addressing scaling properties of the method, artificial forcings implemented to ensure constant density across the full simulation despite changing thermodynamic properties of the simulated media, the possible relation between an AdResS system on the one hand and a phase transition phenomenon on the other, and peculiarities of the SPC/E water model.

  15. Ab initio calculation of atomic interactions on Al(110): implications for epitaxial growth

    NASA Astrophysics Data System (ADS)

    Fichthorn, Kristen; Tiwary, Yogesh

    2007-03-01

    Using first-principles calculations based on density-functional theory, we resolved atomic interactions between adsorbed Al atoms on Al(110). Relevant pair and trio interactions were quantified. We find that pair interactions extend to the third in-channel and second cross-channel neighbor on the anisotropic (110) surface. Beyond these distances, pair interactions are negligible. The nearest-neighbor interaction in the in-channel direction is attractive, but nearest-neighbor cross-channel interaction is repulsive. While nearest-neighbor, cross-channel repulsion does not support the experimental observation of 3D hut formation in Al/Al(110) homoepitaxial growth [1], we find that trio interactions can be significant and attractive and they support cross-channel bonding. The pair and trio interactions have direct and indirect components. We have quantified the electronic and elastic components of the indirect, substrate-mediated interactions. We also probe the influence of these interactions on the energy barriers for adatom hopping. [1] F. Buatier de Mongeot, W. Zhu, A. Molle, R. Buzio, C. Boragno, U. Valbusa, E. Wang, and Z. Zhang, Phys. Rev. Lett. 91, 016102 (2003).

  16. First principles study of hydrogen bond symmetrization in δ-AlOOH

    NASA Astrophysics Data System (ADS)

    Pillai, Sharad Babu; Jha, Prafulla K.; Padmalal, Akash; Maurya, D. M.; Chamyal, L. S.

    2018-03-01

    The high pressure behaviour of the hydrous mineral δ-AlOOH has been investigated by many experimental and theoretical studies, but the discrepancy in predicting the value of hydrogen symmetrization pressure was not resolved. Here, we investigated the high pressure behaviour of δ-AlOOH using first principles calculations and found that with proper optimization using pressure routine control, local density approximation (LDA) predicts the hydrogen symmetrization pressure as 15 GPa which is in good agreement with the experimentally predicted value which resolves the existing discrepancy and hence proving the validity of LDA in predicting the hydrogen symmetrization pressure. We further studied the compressibility behaviour of δ-AlOOH at low pressures and confirmed the P21nm to Pnnm transition of δ-AlOOH shown by the experimental work [Kuribayashi et al., Phys. Chem. Miner. 41, 303-312 (2014)]. We have also analysed the dependence of elastic constants, elastic moduli, sound velocities, and Raman spectrum of δ-AlOOH with pressure and found that a subtle change in the position of the hydrogen atom at hydrogen symmetrization pressure results into drastic changes in elastic and vibrational properties. Further, this study has been used to discuss the seismic anomalies observed in the upper mantle beneath the Deccan Volcanic Province in India and the Java subduction zone in the eastern flank of the Indian Ocean.

  17. Magnetic and structural X-ray dichroïsms of metallic multilayers

    NASA Astrophysics Data System (ADS)

    Pizzini, Stefania; Fontaine, A.; Baudelet, F.; Minr, S.; Giorgetti, C.; Dartyge, E.; Bobo, J. F.; Piecuch, M.

    1995-05-01

    Fe/Cu and Co/Cu multilayers are intensively studied because of their exceptional magnetic properties, i.e., their giant magnetoresistance and the oscillations of the magnetic coupling between magnetic layers as a function of the thickness of the copper spacer [S.S. Parkin et al., Phys. Rev. Lett. 66 (1991) 2152; F. Petroff et al., Phys. Rev. B 44 (1991) 5355]. Spectroscopic approaches to the understanding of the coupling of ferromagnetic layers through a noble metal layer have been recently introduced, in particular spin-resolved photoemission [N.B. Brookes et al., Phys. Rev. Lett. 67 (1991) 354; C. Carbone et al., PRL 71 (1993) 2805] inverse photoemission [J.E. Ortega et al., Phys. Rev. Lett. 69 (1992) 844; Phys. Rev. B 47 (1993) 1540] and magnetic circular dichroism [S. Pizzini et al., MRS Symp. Proc., vol. 313 (1993); M.G. Samant et al. Phys. Rev. Lett. 72 (1994) 2152; S. Pizzini et al., Phys. Rev. Lett. 74 (1995) 1470]. X-ray absorption spectroscopy appears to be effective both for determination of the local structure, specific to the bidimensionality of the system but also for the electron symmetry-dependent evaluation of the spin polarisation of the noble metal as well as the magnetic element.

  18. Band Alignment for Rectification and Tunneling Effects in Al2O3 Atomic-Layer-Deposited on Back Contact for CdTe Solar Cell.

    PubMed

    Su, Yantao; Xin, Chao; Feng, Yancong; Lin, Qinxian; Wang, Xinwei; Liang, Jun; Zheng, Jiaxin; Lin, Yuan; Pan, Feng

    2016-10-11

    The present work intends to explain why ultrathin Al 2 O 3 atomic-layer-deposited (ALD) on the back contact with rectification and tunneling effects can significantly improve the performance of CdTe solar cells in our previous work [ Liang , J. ; et al. Appl. Phys. Lett. 2015 , 107 , 013907 ]. Herein, we further study the mechanism through establishing the interfacial energy band diagram configuration of the ALD Al 2 O 3 /Cu x Te by experiment of X-ray photoelectron spectroscopy and first-principles calculations and conclude to find the band alignment with optimized layer thickness (about 1 nm ALD Al 2 O 3 ) as the key factor for rectification and tunneling effects.

  19. Dirac cones in artificial structures of 3d transitional-metals doped Mg-Al spinels

    NASA Astrophysics Data System (ADS)

    Lu, Yuan; Feng, Min; Shao, Bin; Zuo, Xu

    2014-05-01

    Motivated by recent theoretical predications for Dirac cone in two-dimensional (2D) triangular lattice [H. Ishizuka, Phys. Rev. Lett. 109, 237207 (2012)], first-principles studies are performed to predict Dirac cones in artificial structures of 3d transitional-metals (TM = Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) doped Mg-Al spinels. In investigated artificial structures, TM dopants substitute specific positions of the B sub-lattice in Mg-Al spinel, and form a quasi-2D triangular lattice in the a-b plane. Calculated results illustrate the existence of the spin-polarized Dirac cones formed in d-wave bands at (around) the K-point in the momentum space. The study provides a promising route for engineering Dirac physics in condensed matters.

  20. Comment on “On the Crooks fluctuation theorem and the Jarzynski equality” [J. Chem. Phys. 129, 091101 (2008)

    PubMed Central

    Adib, Artur B.

    2009-01-01

    It has recently been argued that a self-consistency condition involving the Jarzynski equality (JE) and the Crooks fluctuation theorem (CFT) is violated for a simple Brownian process [L. Y. Chen, J. Chem. Phys.129, 091101 (2008)]. This note adopts the definitions in the original formulation of the JE and CFT and demonstrates the contrary. PMID:19566186

  1. Shock-wave ion acceleration by an ultra-relativistic short laser pulse

    NASA Astrophysics Data System (ADS)

    Zhidkov, A.; Batishchev, O.; Uesaka, M.

    2002-11-01

    Research on ion acceleration by intense short laser pulses grows in the last few years [1-9] because of various applications. However, the study is mainly focused on the forward ion acceleration. We study ion inward acceleration, which in contrast to other mechanisms has density of ions per unit energy not decreased with the laser intensity [8]. Magnetic field generated due to a finite size of laser spot can affect electron distribution. In the present work we study the effect of magnetic field on the shock wave formation and ion acceleration in a solid target via 2D PIC and Vlasov simulation. Though the PIC simulation can provide detailed information, in relativistic plasmas it may not calculate B correctly: (i) too many particles are needed to make B disappeared in thermal plasmas, (ii) local scheme [10] does not satisfy curl(Epl)=0. Therefore, two approaches are used in the present study. [1] S. P. Hatchett et al., Phys. Plas. 7, 2076 (2000); [2] A. Maksimchuk et al., Phys. Rev. Lett. 84, 4108 (2000); [3] E.L. Clark et al., Phys. Rev. Lett. 85, 1654 (2000); [4] A. Zhidkov et al., Phys. Rev. E60, 3273 (1999); E61, R2224 (2000); [5] Y. Murakami et al, Phys. Plasmas 8,4138 (2001); [6] T.Zh. Esirkepov et al, JETP Lett. 70, 82 (1999); [7] A. Pukhov, Phys. Rev. Lett. 86, 3562(2001); [8] A.A. Andreev et al., Plasma Phys. Contr. Fusion (2002); [9] O.V. Batishchev et al., Plasma Phys. Rep. 20, 587 (1994); [10] J. Villasenor et al., Comp. Phys. Comm. 69, 306 (1992).

  2. Comment on `A novel experimental method: Electrochemical detection of phase transition in ferroelectric single crystals', Chem. Phys. Lett. 384 (2004) 262 by K. Gatner and R. Jakubas

    NASA Astrophysics Data System (ADS)

    Ćwikiel, K.; Matlak, M.

    2006-03-01

    We comment the Letter 'A novel experimental method: electrochemical detection of phase transition in ferroelectric single crystals', Chem. Phys. Lett. 384 (2004) 262 by K. Gatner and R. Jakubas. We indicate that the method used in this Letter is not 'A novel method' but the application of the method described in Refs. [M. Matlak, M. Pietruszka, E. Rówiński, Phys. Rev. B 63 (2001) 52101; M. Matlak, M. Pietruszka, E. Rówiński, Phys. Stat. Sol. A 184 (2001) 335; W. Gaweł, E. Zaleska, Z. Sztuba, Met. Sci. Eng. A 324 (2002) 255], well known to Gatner, but not cited in the commented Letter. Additionally Gatner, cooperating with us, has used our TGS samples and published the results in the commented Letter without our knowledge and permission.

  3. Quantum-Critical Dynamics of the Skyrmion Lattice.

    NASA Astrophysics Data System (ADS)

    Green, Andrew G.

    2002-03-01

    Slightly away from exact filling of the lowest Landau level, the quantum Hall ferromagnet contains a finite density of magnetic vortices or Skyrmions[1,2]. These Skyrmions are expected to form a square lattice[3], the low energy excitations of which (translation/phonon modes and rotation/breathing modes) lead to dramatically enhanced nuclear relaxation[4,5]. Upon changing the filling fraction, the rotational modes undergo a quantum phase transition where zero-point fluctuations destroy the orientational order of the Skyrmions[4,6]. I will discuss the effect of this quantum critical point upon nuclear spin relaxation[7]. [1]S. L. Sondhi et al., Phys. Rev. B47, 16419 (1993). [2]S. E. Barrett et al., Phys. Rev. Lett. 74, 5112 (1995), A. Schmeller et al., Phys. Rev. Lett. 75, 4290 (1995). [3]L. Brey et al, Phys. Rev. Lett. 75, 2562 (1995). [4]R. Côté et al., Phys. Rev. Lett. 78, 4825 (1997). [5]R. Tycko et al., Science 268, 1460 (1995). [6]Yu V. Nazarov and A. V. Khaetskii, Phys. Rev. Lett. 80, 576 (1998). [7]A. G. Green, Phys. Rev. B61, R16 299 (2000).

  4. Cubic and orthorhombic structures of aluminum hydride Al H3 predicted by a first-principles study

    NASA Astrophysics Data System (ADS)

    Ke, Xuezhi; Kuwabara, Akihide; Tanaka, Isao

    2005-05-01

    The most stable structure of aluminum hydride AlH3 is believed to be a hexagonal symmetry. However, using the density functional theory, we have identified two more stable structures for the AlH3 with the cubic and orthorhombic symmetries. Based on the quasiharmonic approximation, the cubic and orthorhombic AlH3 are almost degenerate when the zero-point energies are included. The geometric and electronic structures, the phonon, and the thermodynamic properties for the hexagonal, cubic, and orthorhombic AlH3 have been studied by means of density functional theory and direct ab initio force constant approach. The calculated electronic structures, phonon density of states, and thermodynamic functions [including S(T) and H(T)-H(0) ] for the three hydrides are similar. The results show that these three hydrides have negative enthalpies of formation, but positive free energies of formation. This conclusion is the same as that made by Wolverton for the hexagonal AlH3 [Phys. Rev. B 69, 144109 (2004)]. The thermodynamic properties indicate that the orthorhombic and cubic AlH3 should be more difficult to dissociate than the hexagonal AlH3 .

  5. Ultra-High Precision Half-Life Measurement for the Superallowed &+circ; Emitter ^26Al^m

    NASA Astrophysics Data System (ADS)

    Finlay, P.; Demand, G.; Garrett, P. E.; Leach, K. G.; Phillips, A. A.; Sumithrarachchi, C. S.; Svensson, C. E.; Triambak, S.; Grinyer, G. F.; Leslie, J. R.; Andreoiu, C.; Cross, D.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Djongolov, M.; Ettenauer, S.; Hackman, G.; Pearson, C. J.; Williams, S. J.

    2009-10-01

    The calculated nuclear structure dependent correction for ^26Al^m (δC-δNS= 0.305(27)% [1]) is smaller by nearly a factor of two than the other twelve precision superallowed cases, making it an ideal case to pursue a reduction in the experimental errors contributing to the Ft value. An ultra-high precision half-life measurement for the superallowed &+circ; emitter ^26Al^m has been made at the Isotope Separator and Accelerator (ISAC) facility at TRIUMF in Vancouver, Canada. A beam of ˜10^5 ^26Al^m/s was delivered in October 2007 and its decay was observed using a 4π continuous gas flow proportional counter as part of an ongoing experimental program in superallowed Fermi β decay studies. With a statistical precision of ˜0.008%, the present work represents the single most precise measurement of any superallowed half-life to date. [4pt] [1] I.S. Towner and J.C. Hardy, Phys. Rev. C 79, 055502 (2009).

  6. Ultra-High Precision Half-Life Measurement for the Superallowed &+circ; Emitter ^26Al^m

    NASA Astrophysics Data System (ADS)

    Finlay, P.; Demand, G.; Garrett, P. E.; Leach, K. G.; Phillips, A. A.; Sumithrarachchi, C. S.; Svensson, C. E.; Triambak, S.; Ball, G. C.; Bandyopadhyay, D.; Djongolov, M.; Ettenauer, S.; Hackman, G.; Pearson, C. J.; Williams, S. J.; Andreoiu, C.; Cross, D.; Austin, R. A. E.; Grinyer, G. F.; Leslie, J. R.

    2008-10-01

    The calculated nuclear structure dependent correction for ^26Al^m (δC-δNS= 0.305(27)% [1]) is smaller by nearly a factor of two than the other twelve precision superallowed cases, making it an ideal case to pursue a reduction in the experimental errors contributing to the Ft value. An ultra-high precision half-life measurement for the superallowed &+circ; emitter ^26Al^m has been made using a 4π continuous gas flow proportional counter as part of an ongoing experimental program in superallowed Fermi β decay studies at the Isotope Separator and Accelerator (ISAC) facility at TRIUMF in Vancouver, Canada, which delivered a beam of ˜10^5 ^26Al^m/s in October 2007. With a statistical precision of ˜0.008%, the present work represents the single most precise measurement of any superallowed half-life to date. [1] I.S. Towner and J.C. Hardy, Phys. Rev. C 77, 025501 (2008).

  7. Validation of a [Al18F]PSMA-11 preparation for clinical applications.

    PubMed

    Al-Momani, Ehab; Israel, Ina; Samnick, Samuel

    2017-12-01

    Imaging prostate-specific membrane antigen (PSMA) using positron emission tomography (PET) has been presented so far as the most sensitive and specific with regard to prostate cancer detection, in particular in high-risk prostate cancer patients. Currently, it mainly features Gallium-68 ( 68 Ga) labeled PSMA ligands, notably [ 68 Ga]Glu-urea-Lys(Ahx)-HBED-CC ([ 68 Ga]-PSMA-11) and [ 68 Ga]DOTAGA-FFK (Sub-KuE termed ([ 68 Ga]PSMA-I&T). However, 68 Ga has several shortcomings as radionuclide including a short half-life and non-ideal energies. This has motivated consideration of 18 F-labeled analogues for PET imaging of prostate cancer. Here, we describe a simple synthesis and validation of a fluorine-18 labeled Glu-urea-Lys(Ahx)-HBED-CC ([Al 18 F]PSMA-11) for nuclear medicine applications. An efficient method for preparation of [Al 18 F]PSMA-11 was developed and validated (according to Pharm Eur) for routinely clinical applications. [Al 18 F]PSMA-11 was reproducibly obtained in radiochemical yields of 84 ± 6% (n = 15) and > 98% radiochemical purity using an improved one-step radiofluorination in aqueous solution. The total (production/preparation) time, including purification, pharmacological formulation of the isolated product and the quality control of the injectable solution was less than 60min. The [Al 18 F]PSMA-11 was stable over 4h in 1% EtOH/saline selected as injection solution. The solution was sterile, non-pyrogenic and ready for clinical applications after sterile filtration through a 0.22µm membrane filter under sterile conditions. In addition, [Al 18 F]PSMA-11 exhibited higher uptake and retention in PMSA-expressing LNCap prostate cells as compared to its clinically established 68 Ga-labeled analogues [ 68 Ga]PSMA-11 and [ 68 Ga]PSMA-I&T as well as to [ 68 Ga]NOTA-Bn-PSMA. The simple and fast preparation of [Al 18 F]PSMA-11 combined with its favorable pharmacological properties warrant its translation to a clinical setting. The facile and high

  8. Exponentially damped Lévy flights, multiscaling, and exchange rates

    NASA Astrophysics Data System (ADS)

    Matsushita, Raul; Gleria, Iram; Figueiredo, Annibal; Rathie, Pushpa; Da Silva, Sergio

    2004-02-01

    We employ our previously suggested exponentially damped Lévy flight (Physica A 326 (2003) 544) to study the multiscaling properties of 30 daily exchange rates against the US dollar together with a fictitious euro-dollar rate (Physica A 286 (2000) 353). Though multiscaling is not theoretically seen in either stable Lévy processes or abruptly truncated Lévy flights, it is even characteristic of smoothly truncated Lévy flights (Phys. Lett. A 266 (2000) 282; Eur. Phys. J. B 4 (1998) 143). We have already defined a class of “quasi-stable” processes in connection with the finding that single scaling is pervasive among the dollar price of foreign currencies (Physica A 323 (2003) 601). Here we show that the same goes as far as multiscaling is concerned. Our novel findings incidentally reinforce the case for real-world relevance of the Lévy flights for modeling financial prices.

  9. Generalized statistical complexity measures: Geometrical and analytical properties

    NASA Astrophysics Data System (ADS)

    Martin, M. T.; Plastino, A.; Rosso, O. A.

    2006-09-01

    We discuss bounds on the values adopted by the generalized statistical complexity measures [M.T. Martin et al., Phys. Lett. A 311 (2003) 126; P.W. Lamberti et al., Physica A 334 (2004) 119] introduced by López Ruiz et al. [Phys. Lett. A 209 (1995) 321] and Shiner et al. [Phys. Rev. E 59 (1999) 1459]. Several new theorems are proved and illustrated with reference to the celebrated logistic map.

  10. PREFACE: Prospects in Neutrino Physics 2013 - NuPhys2013

    NASA Astrophysics Data System (ADS)

    2015-04-01

    The first "Prospects in Neutrino Physics 2013 - NuPhys2013" conference was held at the Institute of Physics, IoP, London, 19-20 December 2013 and was attended by about 130 delegates from institutions worldwide. Lunch and coffee breaks allowed discussions among delegates and speakers to take place in an informal setting. This conference is unique in discussing the worldwide strategy to address unresolved issues in neutrino physics, and shape the future directions of particle physics. We discussed the current status and focussed especially on the prospects of future experiments, their performance and physics reach. It is particularly timely due to the recent measurements in neutrino physics and planned worldwide experiments. The following topics were addressed: • Theory and Phenomenology Perspectives • Future Long and Short Baseline Neutrino Oscillation Experiments • Reactor neutrino and flux • Neutrinoless double beta decays • Solar, atmospheric, supernova neutrinos • Neutrino cosmology in which both the phenomenological and experimental aspects were equally addressed. World-leading experts in the different neutrino areas were invited to give review talks. To encourage and facilitate the participation of early-career researchers and PhD students, a poster session formed a key aspect of this meeting. The conference was organized by Francesca Di Lodovico and Silvia Pascoli. It was sponsored by the IoP through their Topic Research Meeting Grant, and also supported by Durham IPPP, ERC-207282, FP7 invisibles project, Queen Mary University of London.

  11. Probing of the pseudogap via thermoelectric properties in the Au-Al-Gd quasicrystal approximant

    NASA Astrophysics Data System (ADS)

    Ishikawa, Asuka; Takagiwa, Yoshiki; Kimura, Kaoru; Tamura, Ryuji

    2017-03-01

    The pseudogap of the recently discovered Au-Al-Gd quasicrystal approximant crystal (AC) is investigated over a wide electron-per-atom (e /a ) ratio of ˜0.5 using thermoelectric properties as an experimental probe. This Au-Al-Gd AC provides an ideal platform for fine probing of the pseudogap among a number of known ACs because the Au-Al-Gd AC possesses an extraordinarily wide single-phase region with respect to the variation in the electron concentration [A. Ishikawa, T. Hiroto, K. Tokiwa, T. Fujii, and R. Tamura, Phys. Rev. B 93, 024416 (2016), 10.1103/PhysRevB.93.024416], in striking contrast to, for instance, binary stoichiometric C d6R ACs. As a result, a salient peak structure is observed in the Seebeck coefficient, S , with the composition as well as that of the power factor S2σ , in addition to a gradual variation in the conductivity, σ , and S . These two features are directly associated with rapid and slow variations, respectively, of spectral conductivity σ (E ) , and hence the fine structure inside the pseudogap, in the vicinity of the Fermi level EF. Based on the observed continuous variation of the Fermi wave vector reported in the previous experimental work, fine tuning of EF toward an optimal position was attempted, which led to the successful observation of a sharp peak in S2σ with a value of ˜270 μ W /m .K2 at 873 K. This is the highest value ever reported among both Tsai-type and Bergman-type compounds. The dimensionless figure of merit was determined as 0.026 at 873 K, which is also the highest reported among both Tsai-type and Bergman-type compounds.

  12. EDITORIAL: Annual prizes for best papers

    NASA Astrophysics Data System (ADS)

    2006-09-01

    2005 Roberts Prize The publishers of Physics in Medicine and Biology (PMB) in association with the Institute of Physics and Engineering in Medicine (IPEM) jointly award an annual prize for an article published in PMB during the previous year. The following 14 articles, listed below in chronological order, were rated the best of 2005 based on the (two or three) referees' assessments: P Kundrát et al 2005 Probabilistic two-stage model of cell inactivation by ionizing particles Phys. Med. Biol. 50 1433-47 D Arora et al 2005 Direct thermal dose control of constrained focused ultrasound treatments: phantom and in vivo evaluation Phys. Med. Biol. 50 1919-35 J S Dysart et al 2005 Characterization of Photofrin photobleaching for singlet oxygen dose estimation during photodynamic therapy of MLL cells in vitro Phys. Med. Biol. 50 2597-616 M Defrise et al 2005 Fourier rebinning of time-of-flight PET data Phys. Med. Biol. 50 2749-63 Z Su et al 2005 Systematic investigation of the signal properties of polycrystalline HgI2 detectors under mammographic, radiographic, fluoroscopic and radiotherapy irradiation conditions Phys. Med. Biol. 50 2907-28 E Bräuer-Krisch et al 2005 New irradiation geometry for microbeam radiation therapy Phys. Med. Biol. 50 3103-11 H C Pyo et al 2005 Identification of current density distribution in electrically conducting subject with anisotropic conductivity distribution Phys. Med. Biol. 50 3183-96 R P Findlay et al 2005 Effects of posture on FDTD calculations of specific absorption rate in a voxel model of the human body Phys. Med. Biol. 50 3825-35 G Alexandrakis et al 2005 Tomographic bioluminescence imaging by use of a combined optical-PET (OPET) system: a computer simulation feasibility study Phys. Med. Biol. 50 4225-41 J Keshvari et al 2005 Comparison of radio frequency energy absorption in ear and eye region of children and adults at 900, 1800 and 2450 MHz Phys. Med. Biol. 50 4355-69 J Laufer et al 2005 In vitro measurements of absolute blood

  13. A comment on "The interaction of X2 (X = F, Cl, and Br) with active sites of graphite" [Xu et al., Chem. Phys. Lett., 418, 413 (2006)

    NASA Astrophysics Data System (ADS)

    Lechner, Christoph; Baranek, Philippe; Vach, Holger

    2018-04-01

    In their article, Xu et al. (2006) present the adsorption energies for the chemisorption of the three halogens F2 , Cl2 , and Br2 on the active sites of graphite. The three investigated systems are the three most stable surfaces, (0 0 1), (1 0 0), and (1 1 0); the latter two are also called zigzag and armchair surface, respectively. Due to some inconsistencies in their article, we re-evaluated the results of Xu et al. in order to investigate the impact on the adsorption energies of the halogens. For the (0 0 1) surface, our results agree with Xu et al. However, for the other two surfaces we find major differences. Contrary to Xu et al., we find that the halogens adsorb the strongest on the zigzag surface. The second strongest adsorption is found on the armchair surface for the symmetric configurations, the third strongest for the asymmetric configurations. Several reasons are given which explain this discrepancy. The most striking source of error in the work of Xu et al. is due to the fact that they did not choose the correct spin multiplicities for the model systems which means that they performed the calculations in excited states. This leads to errors between 50 and 600% for the zigzag surface and 3-42% for the armchair surface.

  14. Addition of NH{sub 3} to Al{sub 3}O{sub 3}{sup -}

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wyrwas, Richard B.; Jarrold, Caroline Chick; Das, Ujjal

    2006-05-28

    Recent computational studies on the addition of ammonia (NH{sub 3}) to the Al{sub 3}O{sub 3}{sup -} cluster anion [A. Guevara-Garcia, A. Martinez, and J. V. Ortiz, J. Chem. Phys. 122, 214309 (2005)] have motivated experimental and additional computational studies, reported here. Al{sub 3}O{sub 3}{sup -} is observed to react with a single NH{sub 3} molecule to form the Al{sub 3}O{sub 3}NH{sub 3}{sup -} ion in mass spectrometric studies. This is in contrast to similarly performed studies with water, in which the Al{sub 3}O{sub 5}H{sub 4}{sup -} product was highly favored. However, the anion PE spectrum of the ammoniated species ismore » very similar to that of Al{sub 3}O{sub 4}H{sub 2}{sup -}. The adiabatic electron affinity of Al{sub 3}O{sub 3}NH{sub 3} is determined to be 2.35(5) eV. Based on comparison between the spectra and calculated electron affinities, it appears that NH{sub 3} adds dissociatively to Al{sub 3}O{sub 3}{sup -}, suggesting that the time for the Al{sub 3}O{sub 3}{sup -}{center_dot}NH{sub 3} complex to either overcome or tunnel through the barrier to proton transfer (which is higher for NH{sub 3} than for water) is short relative to the time for collisional cooling in the experiment.« less

  15. Preliminary Results of T and F Asymmetries for KLambda Photoproduction from the Proton

    NASA Astrophysics Data System (ADS)

    Walford, Natalie; Klein, Franz

    2013-04-01

    The search for undiscovered excited states of the nucleon continues to be a focus of experiments at Jefferson Lab. A large effort has been launched using the CLAS detector to provide the database, which will allow nearly model-independent partial wave analyses to be carried out in the search for such states. Polarization observables play a crucial role in this effort, as they are essential in disentangling overlapping resonant and non-resonant amplitudes. Recent coupled-channel analyses [1] have found strong sensitivity of the K-Lambda channel to several higher mass nucleon resonances. In 2010, double-polarization data were taken at JLab using circularly polarized photons incident on a transversely polarized frozen spin target (FROST) [2] comprising butanol, operated at the low temperature of 30mK. The reaction products were detected in CLAS using tagged photons. We will present preliminary data of the T and F asymmetries of the K-Lambda final state with comparisons to predictions of recent multipole analyses. There are very few published measurements of the T asymmetry and none of the F asymmetry for the K-Lambda channel. This work is the first of its kind and will significantly broaden the world database for this reaction.[4pt] [1] A.V. Anisovich et al., Eur. Phys. J. A48 (2012) 15.2] C.D. Keith et al., Nucl. Instr. Meth. A694 (2012) 27.

  16. Controlling the optical bistability in a multi-level atomic system via similar parameters of quantum well nanostructure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jafarzadeh, H., E-mail: h-jafarzadeh56@yahoo.com

    2015-04-28

    The spontaneously generated coherence (SGC) effects on optical bistability (OB) are investigated in a five-level K-type system. It is found that SGC makes the system phase dependent. Thus, the OB and the absorption behavior of the system can be controlled by the relation phase of applied fields. In addition, the pump field intensity effect on the OB behavior is discussed. The experimental viability of the model in semiconductor quantum well system is also discussed [A. V. Germanenko et al., J. Phys.: Conf. Ser. 376, 012024 (2012); D. S. Chemla et al., IEEE J. Quantum Electron. 20(3), 265 (1984); L. V.more » Butov et al., J. Exp. Theor. Phys. 88(5), 1036 (1999); J. F. Dynes et al., Phys. Rev. Lett. 94, 157403 (2005); S. Schmitt-Rinka et al., Adv. Phys. 38(2), 89 (1989); and H. W. Liu et al., Appl. Phys. Lett. 54, 2082 (1989)].« less

  17. Noether symmetry approach in f(G,T) gravity

    NASA Astrophysics Data System (ADS)

    Shamir, M. Farasat; Ahmad, Mushtaq

    2017-01-01

    We explore the recently introduced modified Gauss-Bonnet gravity (Sharif and Ikram in Eur Phys J C 76:640, 2016), f(G,T) pragmatic with G, the Gauss-Bonnet term, and T, the trace of the energy-momentum tensor. Noether symmetry approach has been used to develop some cosmologically viable f(G,T) gravity models. The Noether equations of modified gravity are reported for flat FRW universe. Two specific models have been studied to determine the conserved quantities and exact solutions. In particular, the well known deSitter solution is reconstructed for some specific choice of f(G,T) gravity model.

  18. Reply to ‘Comment on “On the Clausius equality and inequality”’

    NASA Astrophysics Data System (ADS)

    Anacleto, Joaquim; Pereira, Mário G.; Ferreira, J. M.

    2013-01-01

    We address Bizarro's comment on a paper by Anacleto (2011 Eur. J. Phys. 32 279). Bizarro claims that (i) Anacleto's approach is either incomplete or incorrect; (ii) one problem is the definition of dissipative work; and (iii) additional ambiguities and misconceptions may stem from his explanations. We contend that (i) both authors present exactly the same definition of dissipative work; and (ii) it is possible to obtain a more general expression to evaluate the entropy change that comprises the expressions developed by both authors—indicating that Anacleto's approach is correct and coherent, and that the criticism of the paper is therefore unfounded.

  19. LETTERS AND COMMENTS: Comment on 'The effects of students' reasoning abilities on conceptual understanding and problem-solving skills in introductory mechanics'

    NASA Astrophysics Data System (ADS)

    Coletta, Vincent P.; Phillips, Jeffrey A.; Savinainen, Antti; Steinert, Jeffrey J.

    2008-09-01

    In a recent article, Ates and Cataloglu (2007 Eur. J. Phys. 28 1161-71), in analysing results for a course in introductory mechanics for prospective science teachers, found no statistically significant correlation between students' pre-instruction scores on the Lawson classroom test of scientific reasoning ability (CTSR) and post-instruction scores on the force concept inventory (FCI). As a possible explanation, the authors suggest that the FCI does not probe for skills required to determine reasoning abilities. Our previously published research directly contradicts the authors' finding. We summarize our research and present a likely explanation for their observation of no correlation.

  20. α-cluster states in 46,54Cr from double-folding potentials

    NASA Astrophysics Data System (ADS)

    Mohr, Peter

    2017-10-01

    α-cluster states in 46Cr and 54Cr are investigated in the double-folding model. This study complements a recent similar work by Souza and Miyake, Eur. Phys. J. A 53, 146 (2017), which was based on a specially shaped potential. Excitation energies, reduced widths, intercluster separations, and intra-band transition strengths are calculated and compared to experimental values for the ground state bands in 46Cr and 54Cr . The α-cluster potential is also applied to elastic scattering at low and intermediate energies. Here, as a byproduct, a larger radial extent of the neutron density in 50Ti is found.

  1. [Adaptation of the (18)FDG module for the preparation of a sodium fluoride [(18)F] injection solution in agreement with the United States (USP 32) and European Pharmacopeia (PhEur 6)].

    PubMed

    Martínez, T; Cordero, B; Medín, S; Sánchez Salmón, A

    2011-01-01

    To establish an automated procedure for the preparation of sodium fluoride (18)F injection using the resources available in our laboratory for the preparation of (18)FDG and to analyze the repercussion of the conditioning column of the fluoride ion entrapment on the characteristics of the final product. The sequence of an (18)FDG synthesis module prepared so that it traps the fluoride ion from the cyclotron in ion-exchange resin diluted with 0.9% sodium chloride. The final solution was dosified and sterilized in a final vial in an automatized dispensing module. Three different column conditioning protocols within the process were tested. Quality controls were run according to USP 32 and EurPh 6, adding control of ethanol levels of residual solvent and quality controls of the solution at 8 h post-preparation. Activation of the resin cartridges with ethanol and water was the chosen procedure, with fluoride ion trapping > 95% and pH around 7. Ethanol levels were < 5.000 ppm. Quality controls at 8 h indicated that the solution was in compliance with the USP 32 and EurPh 6 specifications. This is an easy, low-cost, reliable automated method for sodium fluoride preparation in PET facilities with existing equipment for (18)FDG synthesis and quality control. Copyright © 2010 Elsevier España, S.L. y SEMNIM. All rights reserved.

  2. Note: Derivation of two-photon circular dichroism—Addendum to “Two-photon circular dichroism” [J. Chem. Phys. 62, 1006 (1975)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Friese, Daniel H., E-mail: daniel.h.friese@uit.no

    2015-09-07

    This addendum shows the detailed derivation of the fundamental equations for two-photon circular dichroism which are given in a very condensed form in the original publication [I. Tinoco, J. Chem. Phys. 62, 1006 (1975)]. In addition, some minor errors are corrected and some of the derivations in the original publication are commented.

  3. Comment on “On the quantum theory of molecules” [J. Chem. Phys. 137, 22A544 (2012)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sutcliffe, Brian T., E-mail: bsutclif@ulb.ac.be; Woolley, R. Guy

    2014-01-21

    In our previous paper [B. T. Sutcliffe and R. G. Woolley, J. Chem. Phys. 137, 22A544 (2012)] we argued that the Born-Oppenheimer approximation could not be based on an exact transformation of the molecular Schrödinger equation. In this Comment we suggest that the fundamental reason for the approximate nature of the Born-Oppenheimer model is the lack of a complete set of functions for the electronic space, and the need to describe the continuous spectrum using spectral projection.

  4. Nanotwins in Nanocrystalline Mg-Al Alloys: An Insight from High-Resolution TEM and Molecular Dynamics Simulation

    DTIC Science & Technology

    2013-09-25

    Mathaudhu, C.Y.A. Tsao and E.J. Lavernia, Mater. Sci. Eng. A528 (2011) p. 2180. [21] S . Plimpton , J. Comput. Phys. 117 (1995) p. 1. [22] X.-Y. Liu, J.B...grained Mg are identi ? ed and supported with atomistic The views, opinions and/or findings contained in this report are those of the author( s ) and should...MONITORING AGENCY NAME( S ) AND ADDRESS (ES) U.S. Army Research Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 nanocrystalline Mg – Al alloys

  5. Investigation of the High, Finite n Ballooning Mode Limit for Compact Quasi-Axially Symmetric Stellarators

    NASA Astrophysics Data System (ADS)

    Redi, Martha; Canik, John; Fredrickson, E.; Fu, G.; Nuehrenberg, C.; Boozer, A. H.

    2000-10-01

    The standard ballooning-mode beta limit comes from an infinite-n, radially local, ideal magnetohydrodynamic (MHD) calculation. Finite-n ballooning modes have been observed in tokamak plasmas [1]. Investigations of optimized quasiaxially symmetric stellarators with three dimensional, global, ideal MHD codes have recently shown good stability for the external kink, ``vertical" and infinite-n ballooning modes [2,3]. However, infinite-n ballooning stability may be too restrictive, due to its sensitivity to features in the local shear and curvature. The CAS3D [4] code is being used to compare the stability of the high-n ballooning modes to the infinite-n calculations from TERPSICHORE [5]. [1] E. Fredrickson, et al. Phys. Plas. 3 (1996) 2620. [2] G. Fu, Phys. Plas. 7 (2000)1079; Phys. Plas. 7 (2000) 1809. M. Redi, et al. Phys. Plas 7 (2000)1911. [3] A. Reiman, et al., Plas. Phys. Cont. Fus. 41 (1999) B273. [4] C. Nuehrenberg, Phys. Plas. 6 (1999) 275. C. Nuehrenberg, Phys. Plas. 3 (1996) 2401. C. Schwab, Phys. Fluids B5 (1993) 3195. [5] W. A. Cooper, Phys. Plas. 3 (1996) 275.

  6. Fully- and weakly-nonlinear biperiodic traveling waves in shallow water

    NASA Astrophysics Data System (ADS)

    Hirakawa, Tomoaki; Okamura, Makoto

    2018-04-01

    We directly calculate fully nonlinear traveling waves that are periodic in two independent horizontal directions (biperiodic) in shallow water. Based on the Riemann theta function, we also calculate exact periodic solutions to the Kadomtsev-Petviashvili (KP) equation, which can be obtained by assuming weakly-nonlinear, weakly-dispersive, weakly-two-dimensional waves. To clarify how the accuracy of the biperiodic KP solution is affected when some of the KP approximations are not satisfied, we compare the fully- and weakly-nonlinear periodic traveling waves of various wave amplitudes, wave depths, and interaction angles. As the interaction angle θ decreases, the wave frequency and the maximum wave height of the biperiodic KP solution both increase, and the central peak sharpens and grows beyond the height of the corresponding direct numerical solutions, indicating that the biperiodic KP solution cannot qualitatively model direct numerical solutions for θ ≲ 45^\\circ . To remedy the weak two-dimensionality approximation, we apply the correction of Yeh et al (2010 Eur. Phys. J. Spec. Top. 185 97-111) to the biperiodic KP solution, which substantially improves the solution accuracy and results in wave profiles that are indistinguishable from most other cases.

  7. Investigation of the cylindrical vacuum hohlraum energy in the first implosion experiment at the SGIII laser facility

    NASA Astrophysics Data System (ADS)

    Zhang, Huasen; Jiang, Wei; Ge, Fengjun; Song, Peng; Zou, Shiyang; Huang, Tianxuan; Li, Sanwei; Yang, Dong; Li, Zhichao; Hou, Lifei; Guo, Liang; Che, Xingsen; Du, Huabing; Xie, Xufei; He, Xiaoan; Li, Chaoguang; Zha, Weiyi; Xu, Tao; Liu, Yonggang; Wei, Huiyue; Liu, Xiangming; Chen, Zhongjing; Zhang, Xing; Yan, Ji; Pu, Yudong; Peng, Xiaoshi; Li, Yulong; Gu, Peijun; Zheng, Wudi; Liu, Jie; Ding, Yongkun; Zhu, Shaoping

    2018-02-01

    The cylindrical vacuum hohlraum energy at the SGIII laser facility [X. T. He and W. Y. Zhang, Eur. Phys. J. D 44, 227 (2007) and W. Zheng et al., High Power Laser Sci. Eng. 4, e21 (2016)] is investigated for the first time. The hohlraum size and the laser energy are intermediate between the Nova and NIF typical hohlraum experiments. It is found that the SGIII hohlraum exhibits an x-ray conversion efficiency of about 85%, which is more close to that of the NIF hohlraum. The LARED simulations of the SGIII hohlraum underestimate about 15% of the radiation flux measured from the laser entrance hole, while the capsule radiation drive inferred from the x-ray bangtime is roughly consistent with the experiments. The underestimation of the SGIII hohlraum radiation flux is mainly caused by the more enclosed laser entrance hole in the LARED simulation. The comparison between the SGIII and NIF hohlraum simulations by LARED indicates that the LARED generally underestimates the measured radiation flux by 15% for the high x-ray conversion efficiency hohlraums, while it can roughly predict the capsule radiation drive inside the hohlraum.

  8. Analysis of the structure of complex networks at different resolution levels

    NASA Astrophysics Data System (ADS)

    Arenas, A.; Fernández, A.; Gómez, S.

    2008-05-01

    Modular structure is ubiquitous in real-world complex networks, and its detection is important because it gives insights into the structure-functionality relationship. The standard approach is based on the optimization of a quality function, modularity, which is a relative quality measure for the partition of a network into modules. Recently, some authors (Fortunato and Barthélemy 2007 Proc. Natl Acad. Sci. USA 104 36 and Kumpula et al 2007 Eur. Phys. J. B 56 41) have pointed out that the optimization of modularity has a fundamental drawback: the existence of a resolution limit beyond which no modular structure can be detected even though these modules might have their own entity. The reason is that several topological descriptions of the network coexist at different scales, which is, in general, a fingerprint of complex systems. Here, we propose a method that allows for multiple resolution screening of the modular structure. The method has been validated using synthetic networks, discovering the predefined structures at all scales. Its application to two real social networks allows us to find the exact splits reported in the literature, as well as the substructure beyond the actual split.

  9. Corrigendum to ;Lotka-Volterra systems satisfying a strong Painlevé property; [Phys. Lett. A 380 (47) (2016) 3977-3982

    NASA Astrophysics Data System (ADS)

    Bountis, Tassos; Vanhaecke, Pol

    2017-12-01

    The comment made after the proof of Proposition 3.3, in our paper [T. Bountis, P. Vanhaecke, Lotka-Volterra systems satisfying a strong Pailevé property, Phys. Lett. A 380 (47) (2016) 3977-3982], saying that the proposition can be generalized when linear terms are added to the Lotka-Volterra systems considered in the paper, is wrong. In general such deformed systems are not even Hamiltonian.

  10. Response to 'Comment on 'Three-dimensional numerical investigation of electron transport with rotating spoke in a cylindrical anode layer Hall plasma accelerator''[Phys. Plasmas 20, 014701 (2013)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tang, D. L.; Qiu, X. M.; Geng, S. F.

    The numerical simulation described in our paper [D. L. Tang et al., Phys. Plasmas 19, 073519 (2012)] shows a rotating dense plasma structure, which is the critical characteristic of the rotating spoke. The simulated rotating spoke has a frequency of 12.5 MHz with a rotational speed of {approx}1.0 Multiplication-Sign 10{sup 6} m/s on the surface of the anode. Accompanied by the almost uniform azimuthal ion distribution, the non-axisymmetric electron distribution introduces two azimuthal electric fields with opposite directions. The azimuthal electric fields have the same rotational frequency and speed together with the rotating spoke. The azimuthal electric fields excite themore » axial electron drift upstream and downstream due to the additional E{sub {theta}} x B field and then the axial shear flow is generated. The axial local charge separation induced by the axial shear electron flow may be compensated by the azimuthal electron transport, finally resulting in the azimuthal electric field rotation and electron transport with the rotating spoke.« less

  11. A Curvilinear Version of a Quasi-3D Nearshore Circulation Model

    DTIC Science & Technology

    2002-01-01

    Warsi, 1998), in comparison to the Cartesian component method (see, for example, Häuser et al., 1985, 1986; Raghunath et al., 1987; Borthwick and Barber...1999. Three-dimensional dispersion of momentum in wave-induced nearshore currents. Eur. J. Mech., 83–101. Raghunath , R., Sengupta, S., Häuser, J., 1987

  12. Response to ``Comment on `Scalings for radiation from plasma bubbles' '' [Phys. Plasmas 18, 034701 (2011)

    NASA Astrophysics Data System (ADS)

    Thomas, A. G. R.

    2011-03-01

    In the preceding Comment, Corde, Stordeur, and Malka claim that the trapping threshold derived in my recent paper is incorrect. Their principal argument is that the elliptical orbits I used are not exact solutions of the equation of motion in the fields of the bubble. The original paper never claimed this—rather I claimed that the use of elliptical orbits was a reasonable approximation, which I based on observations from particle-in-cell simulations. Integration of the equation of motion for analytical expressions for idealized bubble fields (either analytically [I. Kostyukov, E. Nerush, A. Pukhov, and V. Seredov, Phys. Rev. Lett. 103, 175003 (2009)] or numerically [S. Corde, A. Stordeur, and V. Malka, "Comment on `Scalings for radiation from plasma bubbles,' " Phys. Plasmas 18, 034701 (2011)]) produces a trapping threshold wholly inconsistent with experiments and full particle-in-cell (PIC) simulations (e.g., requiring an estimated laser intensity of a0˜30 for ne˜1019 cm-3). The inconsistency in the particle trajectories between PIC and the numeric model used by the comment authors arises due to the fact that the analytical fields are only approximately true for "real" plasma bubbles, and lack certain key features of the field structure. Two possible methods of resolution to this inconsistency are either to find ever more complicated but accurate models for the bubble fields or to find approximate solutions to the equations of motion that capture the essential features of the self-consistent electron trajectories. The latter, heuristic approach used in my recent paper produced a threshold that is better matched to experimental observations. In this reply, I will also revisit the problem and examine the relationship between bubble radius and electron momentum at the point of trapping without reference to a particular trajectory.

  13. Fully relativistic B-spline R-matrix calculations for electron collisions with xenon

    NASA Astrophysics Data System (ADS)

    Bartschat, Klaus; Zatsarinny, Oleg

    2009-05-01

    We have applied our recently developed fully relativistic Dirac B-spline R-matrix (DBSR) code [1] to calculate electron scattering from xenon atoms. Results from a 31-state close-coupling model for the excitation function of the metastable (5p^5 6s) J=0,2 states show excellent agreement with experiment [2], thereby presenting a significant improvement over the most sophisticated previous Breit-Pauli calculations [3,4]. This allows for a detailed and reliable analysis of the resonance structure. The same model is currently being used to calculate electron-impact excitation from the metastable J=2 state. The results will be compared with recent experimental data [5] and predictions from other theoretical models [6,7]. [1] O. Zatsarinny and K. Bartschat, Phys. Rev. A 77 (2008) 062701. [2] S. J. Buckman et al., J. Phys. B 16 (1983) 4219. [3] A. N. Grum-Grzhimailo and K. Bartschat, J. Phys. B 35 (2002) 3479. [4] M. Allan et al., Phys. Rev. A 74 (2006) 030701(R). [5] R. O. Jung et al., Phys. Rev. A 72 (2005) 022723. [6] R. Srivastava et al., Phys. Rev. A 74 (2006) 012715. [7] J. Jiang et al., J. Phys. B 41 (2008) 245204.

  14. Origins of low resistivity in Al ion-implanted ZnO bulk single crystals

    NASA Astrophysics Data System (ADS)

    Oga, T.; Izawa, Y.; Kuriyama, K.; Kushida, K.; Kinomura, A.

    2011-06-01

    The origins of low resistivity in Al ion-implanted ZnO bulk single crystals are studied by combining Rutherford backscattering spectroscopy (RBS), nuclear reaction analysis (NRA), photoluminescence (PL), and Van der Pauw methods. The Al-ion implantation (peak concentration: 2.6 × 1020cm-3) into ZnO is performed using a multiple-step energy. The resistivity decreases from ˜104 Ω cm for un-implanted ZnO to 1.4 × 10-1 Ω cm for as-implanted, and reaches 6.0 × 10-4 Ω cm for samples annealed at 1000 °C. RBS and NRA measurements for as-implanted ZnO suggest the existence of the lattice displacement of Zn (Zni) and O (Oi), respectively. After annealing at 1000 °C, the Zni related defects remain and the Oi related defects disappear. The origin of the low resistivity in the as-implanted sample is attributed to the Zni (˜30 meV [Look et al., Phys. Rev. Lett. 82, 2552 (1999)]). In contrast, the origin of the low resistivity in the sample annealed at 1000 °C is assigned to both of the Zni related defects and the electrically activated Al donor. A new PL emission appears at around 3.32 eV after annealing at 1000 °C, suggesting electrically activated Al donors.

  15. Erratum: Measurement of σ(e+e-→ψ(3770)→hadrons) at Ec.m.=3773MeV [Phys. Rev. Lett. 96, 092002 (2006)

    NASA Astrophysics Data System (ADS)

    Besson, D.; Pedlar, T. K.; Cronin-Hennessy, D.; Gao, K. Y.; Gong, D. T.; Hietala, J.; Kubota, Y.; Klein, T.; Lang, B. W.; Poling, R.; Scott, A. W.; Smith, A.; Dobbs, S.; Metreveli, Z.; Seth, K. K.; Tomaradze, A.; Zweber, P.; Ernst, J.; Arms, K.; Severini, H.; Dytman, S. A.; Love, W.; Mehrabyan, S.; Mueller, J. A.; Savinov, V.; Li, Z.; Lopez, A.; Mendez, H.; Ramirez, J.; Huang, G. S.; Miller, D. H.; Pavlunin, V.; Sanghi, B.; Shipsey, I. P. J.; Adams, G. S.; Anderson, M.; Cummings, J. P.; Danko, I.; Napolitano, J.; He, Q.; Muramatsu, H.; Park, C. S.; Thorndike, E. H.; Coan, T. E.; Gao, Y. S.; Liu, F.; Artuso, M.; Boulahouache, C.; Blusk, S.; Butt, J.; Li, J.; Menaa, N.; Mountain, R.; Nisar, S.; Randrianarivony, K.; Redjimi, R.; Sia, R.; Skwarnicki, T.; Stone, S.; Wang, J. C.; Zhang, K.; Csorna, S. E.; Bonvicini, G.; Cinabro, D.; Dubrovin, M.; Lincoln, A.; Briere, R. A.; Chen, G. P.; Chen, J.; Ferguson, T.; Tatishvili, G.; Vogel, H.; Watkins, M. E.; Rosner, J. L.; Adam, N. E.; Alexander, J. P.; Berkelman, K.; Cassel, D. G.; Duboscq, J. E.; Ecklund, K. M.; Ehrlich, R.; Fields, L.; Gibbons, L.; Gray, R.; Gray, S. W.; Hartill, D. L.; Heltsley, B. K.; Hertz, D.; Jones, C. D.; Kandaswamy, J.; Kreinick, D. L.; Kuznetsov, V. E.; Mahlke-Krüger, H.; Meyer, T. O.; Onyisi, P. U. E.; Patterson, J. R.; Peterson, D.; Phillips, E. A.; Pivarski, J.; Riley, D.; Ryd, A.; Sadoff, A. J.; Schwarthoff, H.; Shi, X.; Stroiney, S.; Sun, W. M.; Wilksen, T.; Weinberger, M.; Athar, S. B.; Avery, P.; Breva-Newell, L.; Patel, R.; Potlia, V.; Stoeck, H.; Yelton, J.; Rubin, P.; Cawlfield, C.; Eisenstein, B. I.; Karliner, I.; Kim, D.; Lowrey, N.; Naik, P.; Sedlack, C.; Selen, M.; White, E. J.; Wiss, J.; Shepherd, M. R.; Asner, D. M.; Edwards, K. W.

    2010-04-01

    We have updated our measurement of the cross section for e^+e^- -> psi(3770) -> hadrons, our publication "Measurement of sigma(e^+e^- -> psi(3770) -> hadrons) at E_{c.m.} = 3773 MeV", arXiv:hep-ex/0512038, Phys.Rev.Lett.96, 092002 (2006). Simultaneous with this arXiv update, we have published an erratum in Phys.Rev.Lett.104, 159901 (2010). There, and in this update, we have corrected a mistake in the computation of the error on the difference of the cross sections for e^+e^- -> psi(3770) -> hadrons and e^+e^- -> psi(3770) -> DDbar. We have also used a more recent CLEO measurement of cross section for e^+e^- -> psi(3770) -> DDbar. From this, we obtain an upper limit on the branching fraction for psi(3770) -> non-DDbar of 9% at 90% confidence level.

  16. h -AlN-Mg(OH)2 van der Waals bilayer heterostructure: Tuning the excitonic characteristics

    NASA Astrophysics Data System (ADS)

    Bacaksiz, C.; Dominguez, A.; Rubio, A.; Senger, R. T.; Sahin, H.

    2017-02-01

    Motivated by recent studies that reported the successful synthesis of monolayer Mg (OH) 2 [Suslu et al., Sci. Rep. 6, 20525 (2016), 10.1038/srep20525] and hexagonal (h -)AlN [Tsipas et al., Appl. Phys. Lett. 103, 251605 (2013), 10.1063/1.4851239], we investigate structural, electronic, and optical properties of vertically stacked h -AlN and Mg (OH) 2 , through ab initio density-functional theory (DFT), many-body quasiparticle calculations within the GW approximation and the Bethe-Salpeter equation (BSE). It is obtained that the bilayer heterostructure prefers the A B' stacking having direct band gap at the Γ with Type-II band alignment in which the valance band maximum and conduction band minimum originate from different layer. Regarding the optical properties, the imaginary part of the dielectric function of the individual layers and heterobilayer are investigated. The heterobilayer possesses excitonic peaks, which appear only after the construction of the heterobilayer. The lowest three exciton peaks are analyzed in detail by means of band decomposed charge density and the oscillator strength. Furthermore, the wave function calculation shows that the first peak of the heterobilayer originates from spatially indirect exciton where the electron and hole localized at h -AlN and Mg (OH) 2 , respectively, which is important for the light harvesting applications.

  17. Ir-192 HDR transit dose and radial dose function determination using alanine/EPR dosimetry

    NASA Astrophysics Data System (ADS)

    Guzmán Calcina, Carmen S.; de Almeida, Adelaide; Oliveira Rocha, José R.; Abrego, Felipe Chen; Baffa, Oswaldo

    2005-03-01

    Source positioning close to the tumour in high dose rate (HDR) brachytherapy is not instantaneous. An increment of dose will be delivered during the movement of the source in the trajectory to its static position. This increment is the transit dose, often not taken into account in brachytherapeutic treatment planning. The transit dose depends on the prescribed dose, number of treatment fractions, velocity and activity of the source. Combining all these factors, the transit dose can be 5% higher than the prescribed absorbed dose value (Sang-Hyun and Muller-Runkel, 1994 Phys. Med. Biol. 39 1181 8, Nath et al 1995 Med. Phys. 22 209 34). However, it cannot exceed this percentage (Nath et al 1995). In this work, we use the alanine-EPR (electron paramagnetic resonance) dosimetric system using analysis of the first derivative of the signal. The transit dose was evaluated for an HDR system and is consistent with that already presented for TLD dosimeters (Bastin et al 1993 Int. J. Radiat. Oncol. Biol. Phys. 26 695 702). Also using the same dosimetric system, the radial dose function, used to evaluate the geometric dose degradation around the source, was determined and its behaviour agrees better with those obtained by Monte Carlo simulations (Nath et al 1995, Williamson and Nath 1991 Med. Phys. 18 434 48, Ballester et al 1997 Med. Phys. 24 1221 8, Ballester et al 2001 Phys. Med. Biol. 46 N79 90) than with TLD measurements (Nath et al 1990 Med. Phys. 17 1032 40).

  18. Ir-192 HDR transit dose and radial dose function determination using alanine/EPR dosimetry.

    PubMed

    Calcina, Carmen S Guzmán; de Almeida, Adelaide; Rocha, José R Oliveira; Abrego, Felipe Chen; Baffa, Oswaldo

    2005-03-21

    Source positioning close to the tumour in high dose rate (HDR) brachytherapy is not instantaneous. An increment of dose will be delivered during the movement of the source in the trajectory to its static position. This increment is the transit dose, often not taken into account in brachytherapeutic treatment planning. The transit dose depends on the prescribed dose, number of treatment fractions, velocity and activity of the source. Combining all these factors, the transit dose can be 5% higher than the prescribed absorbed dose value (Sang-Hyun and Muller-Runkel, 1994 Phys. Med. Biol. 39 1181-8, Nath et al 1995 Med. Phys. 22 209-34). However, it cannot exceed this percentage (Nath et al 1995). In this work, we use the alanine-EPR (electron paramagnetic resonance) dosimetric system using analysis of the first derivative of the signal. The transit dose was evaluated for an HDR system and is consistent with that already presented for TLD dosimeters (Bastin et al 1993 Int. J. Radiat. Oncol. Biol. Phys. 26 695-702). Also using the same dosimetric system, the radial dose function, used to evaluate the geometric dose degradation around the source, was determined and its behaviour agrees better with those obtained by Monte Carlo simulations (Nath et al 1995, Williamson and Nath 1991 Med. Phys. 18 434-48, Ballester et al 1997 Med. Phys. 24 1221-8, Ballester et al 2001 Phys. Med. Biol. 46 N79-90) than with TLD measurements (Nath et al 1990 Med. Phys. 17 1032-40).

  19. Comment on "Not all counterclockwise thermodynamic cycles are refrigerators" [Am. J. Phys. 84, 413-418 (2016)

    NASA Astrophysics Data System (ADS)

    Bizarro, João P. S.

    2017-11-01

    Contrary to what Dickerson and Mottmann [Am. J. Phys. 84, 413-418 (2016)] state, the temperatures at which a refrigerator's working fluid absorbs heat need not always lie below those at which it expels heat; nor must a refrigerator's thermodynamic cycle have two adiabats. Moreover, what Dickerson and Mottmann call a "comparison Carnot cycle" cannot always be defined. These conclusions are illustrated here using a counter-clockwise Stirling cycle without regeneration. A refrigerator's cold reservoir can absorb some heat and its hot reservoir can expel some heat, so long as the net heat flow is still out of the cold reservoir and into the hot reservoir.

  20. Sound velocity of 23 Å phase (a new Al-bearing hydrous Mg-silicate) to 14 GPa

    NASA Astrophysics Data System (ADS)

    Cai, N.; Chen, T.; Qi, X.; Inoue, T.; Li, B.

    2016-12-01

    Dense hydrous phases are believed to play an important role in transporting water back into the deep interior of the Earth. Recently, a new Al-bearing hydrous Mg-silicate named 23 Å phase (ideal composition Mg11Al2Si4O16(OH)12) was reported (Cai et al., 2015), which could be a very important hydrous phase in subducting slab. Here for the first time we measured the compressional and shear wave velocities of this new hydrous phase under mantle pressures. The sample was synthesized at 10 GPa and 1000 ºC using the chemical mixture of stoichiometric as starting materials. The recovered sample was then crushed into fine powder and hot pressed at 10 GPa and 900 ºC for 3 hours. X-ray diffraction, density measurement, and SEM characterization indicated that the specimen is nearly a pure phase, 20 µm in grain size, with a bulk density of 3.004 g/cm3. The acoustic measurements were conducted in a 1000-ton uniaxial split-cylinder multi-anvil apparatus using ultrasonic interferometry techniques (Li et al., 1996) up to 14 GPa at room temperature. The pressures were determined in situ by using alumina buffer rod as a pressure marker (Wang et al., 2015). A dual-mode piezoelectric transducer enables us to measure P and S wave travel times simultaneously, which in turn allows for a precise determination of the sound velocities and elastic bulk and shear moduli at high pressures. Preliminary results suggest that the velocities, (especially for S wave) of this 23 Å phase are slower than that of phase A and most of the mantle minerals. These results may have important implications for understanding some localized low velocity zones in subduction zones. Cai, N., T. Inoue, K. Fujino, H. Ohfuji and H. Yurimoto (2015) A Possible New Al-bearing Hydrous Mg-silicate (23 Å phase) in the Deep Upper Mantle. Am Mineral. 100: 2330-2335. Li, B., I. Jackson, T. Gasparik, and R. C. Liebermann (1996), Elastic wave velocity measurement in multianvil apparatus to 10 GPa using ultrasonic

  1. Strengthening of NiAl Matrix Composites

    DTIC Science & Technology

    1991-10-01

    taille des sous-grains. Les donn&s obtenues pour une serie d’exp&iences indiquent que hit densitc de dislocations croit lorsque Ia fraction volumique de...electrical discharge 8. H. Fujita. T. Tabata , K. Yoshida. N. Summida and S. Katagiri, Japan J. appl. Phys. II, 1522 (1972).machining, dimpling and ion...milling does not intro- 9. H. Fujita and T. Tabata , Japan J. appl. Phys. 12, 471 duce dislocations into the matrix. (1973). * In order to obtain realistic

  2. Spin-Torque Diode Effect in Magnetic Tunnel Junctions

    NASA Astrophysics Data System (ADS)

    Suzuki, Yoshishige

    2007-03-01

    Spin-injection magnetization switching (SIMS) technique [1] made it possible to control magnetization by a direct current. A discovery of spontaneous rf oscillation from CPP-GMR nano-pillars and a real time observation of the switching process have revealed essential amplification function of a precession in the magnetic nano-pillars under a direct current [2]. Beside of those progresses, developments of giant tunneling magneto-resistive (GTMR) effect using an MgO barrier [3] made it possible to utilize a very large resistance change according to the magnetization switching. In this talk, several attempts to utilize interplay between spin-torque and giant-TMR effect will be presented referring to a ``spin-torque diode effect'' [4] and other properties such like rf noise control and possible signal amplification using magnetic tunnel junctions (MTJs). [1] J. C. Slonczewski, J. Magn. Magn. Mater. 159, L1 (1996) , L. Berger, Phys. Rev. B 54, 9353 (1996), and E. B. Myers, et al., Science 285, 867 (1999). [2] S. I. Kiselev et al., Nature 425, 380 (2003), I. N. Krivorotov et al., Science, 307, 228 (2005). [3] W. Wulfhekel, et al. Appl. Phys. Lett. 78, 509--511 (2001), M. Bowen, et al. Appl. Phys. Lett. 79, 1655--1657 (2001), J. Faure-Vincent, et al. Appl. Phys. Lett. 82, 4507--4509 (2003), S. Yuasa, et al., Jpn. J. Appl. Phys. Part 2, 43, L588 (2004), S. Yuasa, et al., Nature Mat. 3, 868 (2004), S. S. P. Parkin et al., Nature Mat. 3, 862 (2004), and D. D. Djayaprawira et al., Appl. Phys. Lett. 86, 092502 (2005). [4] A. A. Tulapurkar, et al., Nature, 438, 339 (2005).

  3. High Tc: The Discovery of RBCO

    NASA Astrophysics Data System (ADS)

    Chu, C. W.

    2007-03-01

    It was said by Emerson that ``there is no history; there is only biography.'' This is especially true when the events are recounted by a person who, himself, has been heavily involved and the line between history and autobiography can become blurred. However, it is reasonable to say that discovery itself is not a series of accidents but an inevitable product of each development stage of scientific knowledge as was also pointed out by Holden et al. (1) The discovery of RBCO (2,3) with R = Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu is no exception. In this presentation, I will briefly recount several events that were crucial to the discovery of RBCO: those before 1986 (4) that sowed the seeds in our group important to our later high temperature superconductivity effort; those in 1986 (5) that were critical to our discovery of the 93 K RBCO soon after the discovery of the 35 K high temperature superconductor by M"uller and Bednorz (6); and those in 1987 when the barrier of the liquid nitrogen boiling temperature of 77 K was finally conquered. 1. G. J. Holton et al., American Scientist 84, 364 (1996). 2. M. K. Wu et al., Phys. Rev. Lett. 58, 908 (1987). 3. P. H. Hor et al., Phys. Rev. Lett. 58, 1891 (1987). 4. C. W. Chu et al., S. S. Comm. 18, 977 (1976); C. W. Chu and V. Diatchenko, Phys. Rev. Lett. 41, 572 (1978); T. H. Lin et al., Phys. Rev. B(RC) 29, 1493 (1984); J. H. Lin et al., J. Low Temp. Phys. 58, 363 (1985). 5. C. W. Chu et al., Phys. Rev. Lett. 58, 405 (1987); C. W. Chu et al., Science 235, 567 (1987). 6. J. G. Bednorz and K. A. M"uller, Z. Phys. B64, 189 (1986).

  4. A review of astrophysics experiments on intense lasers

    NASA Astrophysics Data System (ADS)

    Remington, B. A.

    1999-11-01

    Modern, high power laser facilities open new possibilities for simulating astrophysical systems in the laboratory.(S.J. Rose, Laser & Part. Beams 9, 869 (1991); B.H. Ripin et al., Laser & Part. Beams 8, 183 (1990); B.A. Remington et al., Science 284, 1488 (1999); H. Takabe et al., Plasma Phys. Contr. Fusion 41, A75 (1999); R.P. Drake, J. Geophys. Res. 104, 14505 (1999).) Scaled investigations of the hydrodynamics.(J. Kane et al., Phys. Plasmas 6, 2065 (1999); R.P. Drake et al., Ap. J. 500, L157 (1998); D. Ryutov et al., Ap. J. 518, 821 (1999).) and radiative transfer.(J. Wark et al., Phys. Plasmas 4, 2004 (1997); P.K. Patel et al., JQSRT 58, 835 (1997).) relevant to supernovae, and opacities relevant to stellar interiors.(F.J. Rogers and C.A. Iglesias, Science 263, 50 (1994); H. Merdji et al., JSQRT 58, 783 (1997).) are now possible with laser experiments. Equations of state relevant to the interiors of giant planets and brown dwarfs are also being experimentally accessed.(G.W. Collins et al., Science 281, 1178 (1998); A. Benuzzi et al., Phys. Rev. E 54, 2162 (1996).) With the construction of the NIF laser in the U.S., and the LIL and LMJ lasers in France, controlled investigations of thermonuclear burn physics will become possible in the next decade. And with existing and future ultra-high intensity short pulse lasers, investigations of relativistic astrophysical plasmas are becoming possible.(M.H. Key et al., Phys. Plasmas 5, 1966 (1998); F. Pegoraro et al., Plasma Phys. Contr. Fus. 39, B261 (1997).) A review of laboratory astrophysics experiments using intense lasers will be presented, and the potential for the future will be discussed.

  5. Accurate atomic data for xenon: energy levels, oscillator strengths, and electron collision cross sections

    NASA Astrophysics Data System (ADS)

    Bartschat, Klaus; Zatsarinny, Oleg

    2009-10-01

    We have applied our recently developed fully relativistic Dirac B-spline R-matrix (DBSR) code [1] to calculate the atomic structure (energy levels and oscillator strengths) as well as electron scattering from xenon atoms. Results from a 31-state close-coupling model for the excitation function of the metastable (5p^5 6s) J=0,2 states show excellent agreement with experiment [2], thereby presenting a significant improvement over the most sophisticated previous Breit-Pauli calculations [3,4]. The same model is currently being used to calculate electron-impact excitation from the metastable J=2 state. The results will be compared with recent experimental data [5] and predictions from other theoretical models [6,7]. Our dataset is an excellent basis for modeling plasma discharges containing xenon.[0pt] [1] O. Zatsarinny and K. Bartschat, Phys. Rev. A 77 (2008) 062701.[0pt] [2] S. J. Buckman et al., J. Phys. B 16 (1983) 4219.[0pt] [3] A. N. Grum-Grzhimailo and K. Bartschat, J. Phys. B 35 (2002) 3479.[0pt] [4] M. Allan et al., Phys. Rev. A 74 (2006) 030701(R).[0pt] [5] R. O. Jung et al., Phys. Rev. A 72 (2005) 022723.[0pt] [6] R. Srivastava et al., Phys. Rev. A 74 (2006) 012715.[0pt] [7] J. Jiang et al., J. Phys. B 41 (2008) 245204.

  6. Annual Gaseous Electronics Conference (44TH) Held in Albuquerque, New Mexico on 22-25 October 1991

    DTIC Science & Technology

    1992-05-01

    Phys. Rev. A 38, 2471 (1988); J. E. Lawler et al., Phys. Rev. A 43, 4427 1991). T. J. Sommerer et al., Phys. Rev. A39, 6356 (1989). EA-2 Diagnostics and...Charged Ions with a Metal Surface.* F.W. MEYER, S.H. OVERBURY, CC. HAVENER, PA. ZEULMANS VAN EMMICHOVEN, and D.M. ZEHNER, ORNL -- Projectile K-Auger

  7. Density profile and breathing mode of strongly correlated spherical Yukawa plasmas

    NASA Astrophysics Data System (ADS)

    Henning, Christian; Fujioka, Kenji; Ludwig, Patrick; Bonitz, Michael

    2007-11-01

    The structure of ``Yukawa balls,'' i.e. spherical 3D dust crystals, which recently have been produced [1], is well explained by computer simulations of charged Yukawa interacting particles within an external parabolic confinement [2]. Dynamical properties (e.g. breathing mode) of these systems were investigated by experiment, simulations as well as theoretically by using the ansatz of a uniform ground state density [3]. Here we show analytically that screening has a dramatic effect on the density profile which decreases away from the center [4,5] and which is in excellent agreement with MD simulations of Yukawa balls. This result is used to improve former calculations of the breathing mode [6].References[1] O. Arp et al. Phys. Rev. Lett. 93, 165004 (2004)[2] M. Bonitz et al., Phys. Rev. Lett. 96, 075001 (2006)[3] T. E. Sheridan, Phys. Plasmas 13, 022106 (2006)[4] C. Henning et al., Phys. Rev. E 74, 056403 (2006)[5] C. Henning at al., Phys. Rev. E (2007)[6] C. Henning at al., submitted for publication

  8. Optical second harmonic spectroscopy of silicon-adsorbate surfaces and silicon nanocrystals

    NASA Astrophysics Data System (ADS)

    Downer, Michael

    2002-03-01

    Second harmonic generation (SHG) provides a surface-specific, noninvasive probe of adsorbates. However, microscopic first-principles theory of adsorbate-specific spectroscopic SHG responses has proven elusive. Here we present experimental SHG spectra for six well-characterized, technologically important Si(001) surfaces in ultrahigh vacuum (UHV): clean Si(001)-2x1 and Si(001) terminated with hydrogen (H), [1] germanium (Ge), Ge and H, [2] boron (B) and B and H. [3] Each adsorbate (combination) alters SHG uniquely. Our microscopic theories based on ab initio pseudopotential or semi-empirical tight-binding (SETB) methods then explain observed trends, and predict new features in unexplored spectral regions. [3,4] Charge transfer among surface bonds is found to govern SHG spectroscopy of surface-adsorbate systems strongly. New results on SHG from Si nanocrystals embedded in SiO2 will also be presented. [5] SHG is sensitive to Si/SiO2 interface states, electrostatic charge on the nanocrystals, and macroscopic particle density gradients. Finally, a new frequency-domain interferometric second-harmonic (FDISH) spectroscopic technique to measure simultaneously the intensity and phase of SH radiation over a broad spectral range without laser tuning will be described. [6] 1. J. Dadap et al., Phys. Rev. B 56, 13367 (1997). 2. P. Parkinson et al., Appl. Phys. B 68, 641 (1999). 3. D. Lim et al., Phys. Rev. Lett. 84, 3406 (2000); Appl. Phys. Lett. 77, 181 (2000). 4. V. Gavrilenko et al., Phys. Rev. B 63, 1653 (2001); M. C. Downer et al., Surf. Interface Anal. 31, 966 (2001); M. C. Downer et al., phys. stat. sol. (a), in press (2001). 5. Y. Jiang et al., Appl. Phys. Lett. 78, 766 (2001). 6. P. T. Wilson et al., Opt. Lett. 24, 496 (1999).

  9. Two-order-parameter description of liquid Al under five different pressures

    NASA Astrophysics Data System (ADS)

    Li, Y. D.; Hao, Qing-Hai; Cao, Qi-Long; Liu, C. S.

    2008-11-01

    In the present work, using the glue potential, the constant pressure molecular-dynamics simulations of liquid Al under five various pressures and a systematic analysis of the local atomic structures have been performed in order to test the two-order-parameter model proposed by Tanaka [Phys. Rev. Lett. 80, 5750 (1998)] originally for explaining the unusual behaviors of liquid water. The temperature dependence of the bond order parameter Q6 in liquid Al under five different pressures can be well fitted by the functional expression (Q6)/(1-Q6)=Q60exp((ΔE-PΔV)/(kBT)) which produces the energy gain ΔE and the volume change upon the formation of a locally favored structure: ΔE=0.025eV and ΔV=-0.27(Å)3 . ΔE is nearly equal to the difference between the average bond energy of the other type I bonds and the average bond energy of 1551 bonds (characterizing the icosahedronlike local structure); ΔV could be explained as the average volume occupied by one atom in icosahedra minus that occupied by one atom in other structures. With the obtained ΔE and ΔV , it is satisfactorily explained that the density of liquid Al displays a much weaker nonlinear dependence on temperature under lower pressures. So it is demonstrated that the behavior of liquid Al can be well described by the two-order-parameter model.

  10. Rotational Spectroscopy of Monofluoroethanol Aggregates with Itself and with Water

    NASA Astrophysics Data System (ADS)

    Thomas, Javix; Huang, Wenyuan; Liu, Xunchen; Jäger, Wolfgang; Xu, Yunjie

    2015-06-01

    Fluoroalcohols are used as common cosolvents for studies of the secondary and tertiary substructures of polypeptides and proteins in aqueous solution. It has been proposed that small fluoroalcohol aggregates are crucial for the protein structural altering process.[1] A rotational spectroscopic study of the monofluoroethanol (MFE) dimer was reported by our group before.[2] In this presentation, we report our recent results on the MFE trimer and MFE-water clusters. We analyze the competitive formation of intra- and intermolecular hydrogen bonds, processes that may be crucial for the changes in protein structure that occur in fluoroalcohol-water solution. We show that the MFE trimer takes on a much different binding topology from the recently reported phenol trimer.[3] The results will also be compared to the closely related 2,2,2-trifluoroethanol systems. [1] H. Reiersen, A. R. Rees, Protein Eng. 2000, 13, 739 - 743. [2] X. Liu, N. Borho, Y. Xu, Chem. Eur. J. 2009, 15, 270 - 277. [3] a) N. A. Seifert, A. L. Steber, J. L. Neill, C. Pérez, D. P. Zaleski, B. H. Pate, A. Lesarri, Phys. Chem. Chem. Phys., 2013, 15, 11468; b) T. Ebata, T. Watanabe, N. Mikami, J. Phys. Chem., 1995, 99, 5761.

  11. Response to ``Comment on `Excitations in photoactive molecules from quantum Monte Carlo' '' [J. Chem. Phys. 122, 087101 (2005)

    NASA Astrophysics Data System (ADS)

    Filippi, Claudia; Buda, Francesco

    2005-02-01

    We find that regions of the excited state potential energy surface of formaldimine, which are accessible from the Franck-Condon configuration, are incorrectly described by the restricted open-shell Kohn-Sham (ROKS) approach. In these regions, the deviations of the ROKS energies from the time-dependent density functional theory results are not a simple shift. Contrary to what is argued in the Comment by Doltsinis and Fink [J. Chem. Phys.XX, XXX (2004)], these differences can play a role in the excited state molecular dynamics of formaldimine at finite temperature.

  12. Derivation of the dipole map

    NASA Astrophysics Data System (ADS)

    Ali, Halima; Punjabi, Alkesh; Boozer, Allen

    2004-09-01

    In our method of maps [Punjabi et al., Phy. Rev. Lett. 69, 3322 (1992), and Punjabi et al., J. Plasma Phys. 52, 91 (1994)], symplectic maps are used to calculate the trajectories of magnetic field lines in divertor tokamaks. Effects of the magnetic perturbations are calculated using the low MN map [Ali et al., Phys. Plasmas 11, 1908 (2004)] and the dipole map [Punjabi et al., Phys. Plasmas 10, 3992 (2003)]. The dipole map is used to calculate the effects of externally located current carrying coils on the trajectories of the field lines, the stochastic layer, the magnetic footprint, and the heat load distribution on the collector plates in divertor tokamaks [Punjabi et al., Phys. Plasmas 10, 3992 (2003)]. Symplectic maps are general, efficient, and preserve and respect the Hamiltonian nature of the dynamics. In this brief communication, a rigorous mathematical derivation of the dipole map is given.

  13. Comment on "Properties of (26)Mg and (26)Si in the sd shell model and the determination of the (25)Al(p,gamma) (26) Si reaction rate"

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chipps, K.; Bardayan, Daniel W; Liang, J Felix

    2011-01-01

    A recent discussion of theoretical work on the {sup 25}Al(p,{gamma}){sup 26}Si astrophysical reaction rate [W.A. Richter, B. Alex Brown, A. Signoracci and M. Wiescher Phys. Rev. C 83 065803 (2011)] omits some current and relevant experimental information in forming its scientific conclusions. Accounting for this new information has the potential to significantly alter the reaction rate derived in the paper.

  14. Temperature-dependent stability of stacking faults in Al, Cu and Ni: first-principles analysis.

    PubMed

    Bhogra, Meha; Ramamurty, U; Waghmare, Umesh V

    2014-09-24

    We present comparative analysis of microscopic mechanisms relevant to plastic deformation of the face-centered cubic (FCC) metals Al, Cu, and Ni, through determination of the temperature-dependent free energies of intrinsic and unstable stacking faults along [1 1̄ 0] and [1 2̄ 1] on the (1 1 1) plane using first-principles density-functional-theory-based calculations. We show that vibrational contribution results in significant decrease in the free energy of barriers and intrinsic stacking faults (ISFs) of Al, Cu, and Ni with temperature, confirming an important role of thermal fluctuations in the stability of stacking faults (SFs) and deformation at elevated temperatures. In contrast to Al and Ni, the vibrational spectrum of the unstable stacking fault (USF[1 2̄ 1]) in Cu reveals structural instabilities, indicating that the energy barrier (γusf) along the (1 1 1)[1 2̄ 1] slip system in Cu, determined by typical first-principles calculations, is an overestimate, and its commonly used interpretation as the energy release rate needed for dislocation nucleation, as proposed by Rice (1992 J. Mech. Phys. Solids 40 239), should be taken with caution.

  15. Three-dimensional Numerical Investigation of Electron Transport with Rotating Spoke in a Cylindrical Anode Layer Hall Plasma Accelerator

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ellison, C. Leland; Matyash, K.; Parker, J. B.

    The oscillation behavior described in [Tang et. al, Phys. Plasmas 19, 073519 (2012)] di ers too greatly from previous experimental and numerical studies to claim observation of the same phenomenon. Most signi cantly, the rotation velocity in [Tang et. al, Phys. Plasmas 19, 073519 (2012)] is three orders of magnitude larger than that of typical \\rotating spoke" phenomena. Several physical and numerical considerations are presented to more accurately understand the numerical results of [Tang et. al, Phys. Plasmas 19, 073519 (2012)] in light of previous studies.

  16. Response to "Comment on 'Stationary self-focusing of Gaussian laser beam in relativistic thermal quantum plasma'" [Phys. Plasmas 21, 064701 (2014)

    NASA Astrophysics Data System (ADS)

    Patil, S. D.; Takale, M. V.

    2014-06-01

    Habibi and Ghamari have presented a Comment on our paper [Phys. Plasmas 20, 072703 (2013)] by examining quantum dielectric response in thermal quantum plasma. They have modeled the relativistic self-focusing of Gaussian laser beam in cold and warm quantum plasmas and reported that self-focusing length does not change in both situations. In this response, we have reached the following important conclusions about the comment itself.

  17. Parameterization of fission barrier heights of medium, heavy and super heavy nuclei

    NASA Astrophysics Data System (ADS)

    Manjunatha, H. C.

    2017-12-01

    A new semi empirical formula is proposed for fission barrier heights of medium, heavy and super heavy nuclei in the atomic number region 50 ≤ Z ≤ 130. The fitting parameters for the proposed formula are obtained by making a polynomial fit to the available theoretical and experimental data. The calculated fission barrier heights are compared with that of experiments and other theoretical models such as SHF(SLy6) (Burvenich et al. in Phys Rev C 69:014307, 2004), SHFB(SkM) (Baran et al. in Nucl Phys A 944:442, 2015), FRLDM (Möller et al. in Phys Rev C 79:064304, 2009), ETFSI (SkSC4) with Skyrme SkSC4 force (Mamdouh et al. in Nucl Phys A 679:337, 2001), WS (Kowal et al. in Phys Rev C 82:014303, 2010) and CDFT(DD-ME2) (Abusara et al. in Phys Rev C 85:024314, 2012). The standard deviation for fission barrier heights produced by present formula is evaluated. The good agreement of present formula with the experiments and other models suggests that the present formula could be used to evaluate the fission barrier heights of medium, heavy and super heavy nuclei in the region 50 ≤ Z ≤ 130. This formula is a first of its kind that produces fission barrier heights of 2858 nuclei with the only simple inputs of only neutron number (N), proton number (Z) and mass number (A).

  18. Parameterization of fission barrier heights of medium, heavy and super heavy nuclei

    NASA Astrophysics Data System (ADS)

    Manjunatha, H. C.

    2018-04-01

    A new semi empirical formula is proposed for fission barrier heights of medium, heavy and super heavy nuclei in the atomic number region 50 ≤ Z ≤ 130. The fitting parameters for the proposed formula are obtained by making a polynomial fit to the available theoretical and experimental data. The calculated fission barrier heights are compared with that of experiments and other theoretical models such as SHF(SLy6) (Burvenich et al. in Phys Rev C 69:014307, 2004), SHFB(SkM) (Baran et al. in Nucl Phys A 944:442, 2015), FRLDM (Möller et al. in Phys Rev C 79:064304, 2009), ETFSI (SkSC4) with Skyrme SkSC4 force (Mamdouh et al. in Nucl Phys A 679:337, 2001), WS (Kowal et al. in Phys Rev C 82:014303, 2010) and CDFT(DD-ME2) (Abusara et al. in Phys Rev C 85:024314, 2012). The standard deviation for fission barrier heights produced by present formula is evaluated. The good agreement of present formula with the experiments and other models suggests that the present formula could be used to evaluate the fission barrier heights of medium, heavy and super heavy nuclei in the region 50 ≤ Z ≤ 130. This formula is a first of its kind that produces fission barrier heights of 2858 nuclei with the only simple inputs of only neutron number (N), proton number (Z) and mass number (A).

  19. Corrigendum to ;Numerical dissipation control in high order shock-capturing schemes for LES of low speed flows; [J. Comput. Phys. 307 (2016) 189-202

    NASA Astrophysics Data System (ADS)

    Kotov, D. V.; Yee, H. C.; Wray, A. A.; Sjögreen, Björn; Kritsuk, A. G.

    2018-01-01

    The authors regret for the typographic errors that were made in equation (4) and missing phrase after equation (4) in the article "Numerical dissipation control in high order shock-capturing schemes for LES of low speed flows" [J. Comput. Phys. 307 (2016) 189-202].

  20. Surface phonons in the topological insulators Bi2Se3 and Bi2Te3

    NASA Astrophysics Data System (ADS)

    Boulares, Ibrahim; Shi, Guangsha; Kioupakis, Emmanouil; Lošťák, Petr; Uher, Ctirad; Merlin, Roberto

    2018-03-01

    Raman scattering [K. M. F. Shahil et al., Appl. Phys. Lett. 96, 153103 (2010), V. Gnezdilov et al., Phys. Rev. B 84, 195118 (2011) and H. -H. Kung et al., Phys. Rev. B 95, 245406 (2017)], inelastic helium scattering [X. Zhu et al., Phys. Rev. Lett. 107, 186102 (2011)] and photoemission experiments [J. A. Sobota et al., Phys. Rev. Lett. 113, 157401 (2014)] on the topological insulators Bi2Se3 and Bi2Te3 show features in the range ∼ 50-160 cm-1, which have been assigned alternatively to Raman-forbidden, bulk infrared modes arising from symmetry breaking at the surface or to surface phonons, which couple to the topologically protected electronic states. Here, we present temperature- and wavelength- dependent Raman studies showing additional modes we ascribe to surface phonons in both Bi2Se3 and Bi2Te3. Our assignment is supported by density functional theory calculations revealing surface phonons at frequencies close to those of the extra peaks in the Raman data. The theoretical results also indicate that these modes are not a consequence of spin-orbit coupling and, thus, that their occurrence is unrelated to the topological properties of these materials.

  1. A Note on ;New Hierarchies of Integrable Lattice Equations and Associated Properties: Darboux Transformation Conservation Laws and Integrable Coupling; [Rep. Math. Phys. 67 (2011), 259

    NASA Astrophysics Data System (ADS)

    Xu, Xi-Xiang

    2016-12-01

    We prove that two new hierarchies of integrable lattice equations in [Rep. Math. Phys.67 (2011), 259] can be respectively changed into the famous relativistic Toda lattice hierarchies in the polynomial and the rational forms by means of a simple transformation.

  2. Dispersion and Reinforcement of Nanotubes in High Temperature Polymers for Ultrahigh Strength and Thermally Conductive Nanocomposites

    DTIC Science & Technology

    2007-10-03

    system lies in the contact resistance which would be discussed later. Figure 49. The surface resistivity of...Shouping Li et al. [62] ZhiMin Dang et al., Appl. Phys. Lett. 2004, 85, 1. [63] B.K. Zhu et al. Composites Science and Technology 2006, 66, 548. [64...Hiroki Ago et al., Phys. Rev. B 2000, 61, 3. [65] Yonglai Yang et al. Nanotechnology 2004, 15, 1545. [66] Xiaofeng Lu, Jiani Zheng, Danming Chao

  3. Intraday return inefficiency and long memory in the volatilities of forex markets and the role of trading volume

    NASA Astrophysics Data System (ADS)

    Shahzad, Syed Jawad Hussain; Hernandez, Jose Areola; Hanif, Waqas; Kayani, Ghulam Mujtaba

    2018-09-01

    We investigate the dynamics of efficiency and long memory, and the impact of trading volume on the efficiency of returns and volatilities of four major traded currencies, namely, the EUR, GBP, CHF and JPY. We do so by implementing full sample and rolling window multifractal detrended fluctuation analysis (MF-DFA) and a quantile-on-quantile (QQ) approach. This paper sheds new light by employing high frequency (5-min interval) data spanning from Jan 1, 2007 to Dec 31, 2016. Realized volatilities are estimated using Andersen et al.'s (2001) measure, while the QQ method employed is drawn from Sim and Zhou (2015). We find evidence of higher efficiency levels in the JPY and CHF currency markets. The impact of trading volume on efficiency is only significant for the JPY and CHF currencies. The GBP currency appears to be the least efficient, followed by the EUR. Implications of the results are discussed.

  4. Permeability of a bubble assembly: From the very dry to the wet limit

    NASA Astrophysics Data System (ADS)

    Rouyer, Florence; Pitois, Olivier; Lorenceau, Elise; Louvet, Nicolas

    2010-04-01

    Bubble assemblies offer the remarkable property of adjusting their packing fraction over three orders of magnitude, thus providing an interesting system for the study of liquid flows through granular matter. Although significant work has been done in several fields of research, e.g., foams, porous media, and suspensions, a complete set of data over such a wide range of porosity ɛ is still lacking. In this paper, we measure the permeability of a bubbly system in the range 0.1<ɛ<0.8 and we connect these new data with a recently published set obtained for foams corresponding to ɛ <0.2 [E. Lorenceau et al., Eur. Phys. J. E 28, 293 (2009)]. Moreover, measurements performed with two different surfactants, the so-called "mobile" and "nonmobile" interfaces, allow us to determine the influence of the bubbles' surface mobility, which is proved to be a significant parameter up to ɛ ≈0.6, thus well above the bubbles packing fraction. Above ɛ ≈0.6, surface elasticity is fully mobilized over the bubbles' surface and the behavior of rigid spheres is observed for both solutions. We show that all the permeability values obtained for the bubble assembly with "nonmobile" interfaces are properly described with the Carman-Kozeny model.

  5. Snake instability of dark solitons across the BEC-BCS crossover: An effective-field-theory perspective

    NASA Astrophysics Data System (ADS)

    Lombardi, G.; Van Alphen, W.; Klimin, S. N.; Tempere, J.

    2017-09-01

    In the present article the snake instability mechanism for dark solitons in superfluid Fermi gases is studied in the context of a recently developed effective field theory [S. N. Klimin et al., Eur. Phys. J. B 88, 122 (2015), 10.1140/epjb/e2015-60213-4]. This theoretical treatment has proven to be suitable to study stable dark solitons in quasi-one-dimensional setups across the BEC-BCS crossover. In this paper the nodal plane of the stable soliton solution is perturbed by adding a transverse modulation. The numerical solution of the system of coupled nonlinear differential equations describing the amplitude of the perturbation leads to an estimate of the growth rate and characteristic length scale of the instability, which are calculated for a wide range of interaction regimes and compared to other theoretical predictions. The behavior of the maximum transverse size that the atomic cloud can have in order to preserve the stability is described across the BEC-BCS crossover. The analysis of the effects of spin imbalance on this critical length reveals a stabilization of the soliton with increasing imbalance and therefore provides the experimental community with a method to achieve the realization of stable solitons in real three-dimensional configurations, without reducing the system dimensionality.

  6. Spin-lattice-coupling-mediated magnetoferroelectric phase transition induced by uniaxial pressure in multiferroic CuFe1 -xMxO2 (M =Ga , Al)

    NASA Astrophysics Data System (ADS)

    Tamatsukuri, Hiromu; Mitsuda, Setsuo; Nakamura, Tenfu; Takata, Kouhei; Nakajima, Taro; Prokes, Karel; Yokaichiya, Fabiano; Kiefer, Klaus

    2017-05-01

    We have investigated magnetic and ferroelectric (dielectric) properties of multiferroic CuFe0.982Ga0.018O2 , CuFe0.965Ga0.035O2 , and CuFe0.95Al0.05O2 under applied uniaxial pressure p up to 600 MPa. Unlike the results of the almost same experiments on CuFeO2 [Tamatsukuri et al., Phys. Rev. B 94, 174402 (2016), 10.1103/PhysRevB.94.174402], we have found that the application of p induces a new ferroelectric phase, which is different from the well-studied spin-driven ferroelectric phase with helical magnetic ordering, in all the doped samples investigated here. We have also constructed the temperature versus p magnetoelectric phase diagrams of the three samples. The ferroelectric polarization in the p -induced ferroelectric phase lies along the [110] direction as in the helical magnetoferroelectric phase, and its value is comparable with or larger than that in the helical magnetoferroelectric phase. The magnetic structure in the p -induced ferroelectric phase seems to be of a collinear sinusoidal type. Although this magnetic structure itself does not break the inversion symmetry, it is considered to play an important role in the origin of ferroelectricity in the p -induced ferroelectric phase through the spin-lattice coupling in this system.

  7. Corrigendum to "Onset of η-nuclear binding in a pionless EFT approach" [Phys. Lett. B 771 (2017) 297-302

    NASA Astrophysics Data System (ADS)

    Barnea, N.; Bazak, B.; Friedman, E.; Gal, A.

    2017-12-01

    A three-body force acting between the η-meson and two nucleons was overlooked inadvertently in the model description and discussion in the published version of our paper "Onset of η-nuclear binding in a pionless EFT approach" [Phys. Lett. B 771 (2017) 297-302] while present in the actual numerical calculations. The stated conclusion that a stabilizing ηNN contact term was not needed is therefore incorrect. Such a three-body force, associated with a new low energy constant dηNNΛ, must be introduced at leading order to stabilize η-nucleus systems.

  8. Scaling analyses of the spectral dimension in 3-dimensional causal dynamical triangulations

    NASA Astrophysics Data System (ADS)

    Cooperman, Joshua H.

    2018-05-01

    The spectral dimension measures the dimensionality of a space as witnessed by a diffusing random walker. Within the causal dynamical triangulations approach to the quantization of gravity (Ambjørn et al 2000 Phys. Rev. Lett. 85 347, 2001 Nucl. Phys. B 610 347, 1998 Nucl. Phys. B 536 407), the spectral dimension exhibits novel scale-dependent dynamics: reducing towards a value near 2 on sufficiently small scales, matching closely the topological dimension on intermediate scales, and decaying in the presence of positive curvature on sufficiently large scales (Ambjørn et al 2005 Phys. Rev. Lett. 95 171301, Ambjørn et al 2005 Phys. Rev. D 72 064014, Benedetti and Henson 2009 Phys. Rev. D 80 124036, Cooperman 2014 Phys. Rev. D 90 124053, Cooperman et al 2017 Class. Quantum Grav. 34 115008, Coumbe and Jurkiewicz 2015 J. High Energy Phys. JHEP03(2015)151, Kommu 2012 Class. Quantum Grav. 29 105003). I report the first comprehensive scaling analysis of the small-to-intermediate scale spectral dimension for the test case of the causal dynamical triangulations of 3-dimensional Einstein gravity. I find that the spectral dimension scales trivially with the diffusion constant. I find that the spectral dimension is completely finite in the infinite volume limit, and I argue that its maximal value is exactly consistent with the topological dimension of 3 in this limit. I find that the spectral dimension reduces further towards a value near 2 as this case’s bare coupling approaches its phase transition, and I present evidence against the conjecture that the bare coupling simply sets the overall scale of the quantum geometry (Ambjørn et al 2001 Phys. Rev. D 64 044011). On the basis of these findings, I advance a tentative physical explanation for the dynamical reduction of the spectral dimension observed within causal dynamical triangulations: branched polymeric quantum geometry on sufficiently small scales. My analyses should facilitate attempts to employ the spectral

  9. Microstructure and magnetic microstructure of the Pr 60Al 10Ni 10Cu 20-xFe x ( x=0, 4, 10, 15, 18) alloys observed by magnetic force microscopy

    NASA Astrophysics Data System (ADS)

    Pang, Z. Y.; Han, S. H.; Wang, Y. T.; Wang, W. H.; Han, B. S.

    2005-03-01

    The microstructure and magnetic microstructure of the Pr 60Al 10Ni 10Cu 20-xFe x ( x=0, 4, 10, 15, 18) alloys have been achieved simultaneously by employing a magnetic force microscope directly on the as-cast cylinder rod surface for the first time. By varying the content of Fe, the microstructure of the Pr-based alloy changes progressively from a full glassy state to a composite state with nanocrystalline particles embedded in the glassy matrix, and finally into a nanostructured state. The accompanying magnetic property gradually changes from paramagnetic to hard. The experiment directly evidences the existence of exchange coupling between the crystallites and the variety of the grain-size-dependent magnetic properties can be well explained by Löffler et al.'s new random-anisotropy model (Löffler, et al., Phys. Rev. Lett. 85 (9) (2000) 1990).

  10. Dynamic metastability in the two-dimensional Potts ferromagnet

    NASA Astrophysics Data System (ADS)

    Ibáñez Berganza, Miguel; Petri, Alberto; Coletti, Pietro

    2014-05-01

    We investigate the nonequilibrium dynamics of the two-dimensional (2D) Potts model on the square lattice after a quench below the discontinuous transition point. By means of numerical simulations of systems with q =12, 24, and 48, we observe the onset of a stationary regime below the temperature-driven transition, in a temperature interval decreasing with the system size and increasing with q. These results obtained dynamically agree with those obtained from the analytical continuation of the free energy [J. L. Meunier and A. Morel, Eur. Phys. J. B 13, 341 (2000), 10.1007/s100510050040], from which metastability in the 2D Potts model results to be a finite-size effect.

  11. A life in statistical mechanics. Part 1: From Chedar in Taceva to Yeshiva University in New York

    NASA Astrophysics Data System (ADS)

    Lebowitz, Joel L.; Bonolis, Luisa

    2017-02-01

    This is the first part of an oral history interview on the lifelong involvement of Joel Lebowitz in the development of statistical mechanics. Here the covered topics include the formative years, which overlapped the tragic period of Nazi power and World War II in Europe, the emigration to the United States in 1946 and the schooling there. It also includes the beginnings and early scientific works with Peter Bergmann, Oliver Penrose and many others. The second part will appear in a forthcoming issue of Eur. Phys. J. H. The text presented here has been revised by the authors based on the original oral history interview conducted by Luisa Bonolis and recorded in Paris, France, 11-16 October 2014.

  12. Electrically induced microflows probed by fluorescence correlation spectroscopy.

    PubMed

    Ybert, C; Nadal, F; Salomé, R; Argoul, F; Bourdieu, L

    2005-03-01

    We report on the experimental characterisation of electrically induced flows at the micrometer scale through Fluorescence Correlation Spectroscopy (FCS) measurements. We stress the potential of FCS as a useful characterisation technique in microfluidics devices for transport properties cartography. The experimental results obtained in a model situation are in agreement with previous calculations (F. Nadal, F. Argoul, P. Kestener, B. Pouligny, C. Ybert, A. Ajdari, Eur. Phys. J. E 9, 387 (2002)) predicting the structure and electric-field dependency of the induced flow. Additionally, the present study evidences a complex behaviour of the probe nanobeads under electric field whose precise understanding might prove relevant for situations where nano-objects interact with an external electric field.

  13. Galilean symmetry in a noncommutative gravitational quantum well

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Saha, Anirban

    2010-06-15

    A thorough analysis of Galilean symmetries for the gravitational well problem on a noncommutative plane is presented. A complete closure of the one-parameter centrally extended Galilean algebra is realized for the model. This implies that the field theoretic model constructed to describe noncommutative gravitational quantum well in [A. Saha, Eur. Phys. J. C 51, 199 (2007).] is indeed independent of the coordinate choice. Hence the energy spectrum predicted by the model can be associated with the experimental results to establish the upper bound on a time-space noncommutative parameter. Interestingly, noncommutativity is shown to increase the gravitational pull on the neutronmore » trapped in the gravitational well.« less

  14. The surprising rolling spool: librational motion and failure of the pure rolling condition

    NASA Astrophysics Data System (ADS)

    Onorato, P.; Malgieri, M.; Mascheretti, P.; De Ambrosis, A.

    2015-05-01

    In a previous work (Onorato P, Malgieri M, Mascheretti P and De Ambrosis A 2014 The surprising rolling spool: experiments and theory from mechanics to phase transitions Eur. J. Phys. 35 055011) an asymmetric rolling spool (ARS) was investigated as a simple model for a second-order phase transition. Here, we deepen the study of this system to address critical aspects related both to the characteristic of the oscillatory anharmonic motion and to the role of friction forces in determining it. The experimental data show that for largely asymmetric bodies the rolling condition is not reliably fulfilled because the intensity of the friction force goes below the needed value to ensure rolling without slipping.

  15. Effects of Ion-ion Collisions and Inhomogeneity in Two-dimensional Simulations of Stimulated Brillouin Backscattering*

    NASA Astrophysics Data System (ADS)

    Cohen, B. I.

    2005-10-01

    Two-dimensional simulations of stimulated Brillouin backscattering (SBBS) with the BZOHAR^1 code have been extended to include ion-ion collisions and spatial nonuniformity in the mean ion flow. BZOHAR hybrid simulations (particle-in-cell kinetic ions and Boltzmann fluid electrons) have shown^2 that SBBS saturation is dominated by ion trapping effects and secondary instability of the primary ion wave (decay into subharmonic ion waves and ion quasi-modes). Here we address the effects of ion collisions^3 on SBBS saturation and employ the efficient Langevin ion collision algorithm of Ref. 4 and the Fokker-Planck collision operator of Ref. 5. We also report simulations of SBBS with a linear gradient in the mean ion drift, which in conjunction with the nonlinear frequency shift due to ion trapping can introduce auto-resonance effects that may enhance reflectivities.^6 For SBBS in a high-gain limit with ion collisions or inhomogeneity, we find that ion trapping and secondary ion wave instabilities are robust saturation mechanisms. *Work performed for US DOE by UC LLNL under Contr. W-7405-ENG-48. ^1B.I. Cohen, et al., Phys. Plasmas 4, 956 (1997). ^2B.I. Cohen, et al., Phys. Plasmas, 12, 052703 (2005),. ^ 3P.W. Rambo, et al., Phys. Rev. Lett. 79, 83 (1997). ^ 4M.E. Jones, et al., J. Comp. Phys. 123, 169, (1996). ^ 5W. M. Manheimer, et al., J. Comp. Phys. 138, 563 (1997). ^ 6E.A. Williams, et al., Phys. Plasmas 11, 231 (2004).

  16. Hypertension-Induced Vascular Remodeling Contributes to Reduced Cerebral Perfusion and the Development of Spontaneous Stroke in Aged SHRSP Rats

    DTIC Science & Technology

    2010-01-01

    recanalization and reperfusion occurs in up to 50% of cases within 24 h of stroke onset ( Kassem -Moussa and Graffagnino, 2002; Merino et al, 2008...stroke-prone spontaneously hypertensive rat. Eur I Pharmacol574:158-71 Kassem -Moussa H, Graffagnino C (2002) Nonocclusion and spontaneous

  17. EDITORIAL: Annual prizes for best papers

    NASA Astrophysics Data System (ADS)

    2007-07-01

    2006 Roberts Prize The publishers of Physics in Medicine and Biology (PMB) in association with the Institute of Physics and Engineering in Medicine (IPEM) jointly award an annual prize for an article published in PMB during the previous year. The following ten articles, listed below in chronological order, were rated the best of 2006 based on the (two or three) referees' assessments: D W Mundy et al 2006 Radiation binary targeted therapy for HER-2 positive breast cancers: assumptions, theoretical assessment and future directions Phys. Med. Biol. 51 1377-91 Y Yang et al 2006 Investigation of optical coherence tomography as an imaging modality in tissue engineering Phys. Med. Biol. 51 1649-59 M Krämer and M Scholz 2006 Rapid calculation of biological effects in ion radiotherapy Phys. Med. Biol. 51 1959-70 P Crespo et al 2006 On the detector arrangement for in-beam PET for hadron therapy monitoring Phys. Med. Biol. 51 2143-63 R J Senden et al 2006 Polymer gel dosimeters with reduced toxicity: a preliminary investigation of the NMR and optical dose-response using different monomers Phys. Med. Biol. 51 3301-14 J Wang et al 2006 FDTD calculation of whole-body average SAR in adult and child models for frequencies from 30 MHz to 3 GHz Phys. Med. Biol. 51 4119-27 C A T Van den Berg et al 2006 The use of MR B+1 imaging for validation of FDTD electromagnetic simulations of human anatomies Phys. Med. Biol. 51 4735-46 S Qin and K W Ferrara 2006 Acoustic response of compliable microvessels containing ultrasound contrast agents Phys. Med. Biol. 51 5065-88 R Kramer et al 2006 Skeletal dosimetry in the MAX06 and the FAX06 phantoms for external exposure to photons based on vertebral 3D-microCT images Phys. Med. Biol. 51 6265-89 R Leiderman et al 2006 Coupling between elastic strain and interstitial fluid flow: ramifications for poroelastic imaging Phys. Med. Biol. 51 6291-313 An IPEM college of jurors then assessed and rated these papers in order to choose a winner. We have much

  18. Questioning the application of risk of bias tools in appraising evidence from natural experimental studies: critical reflections on Benton et al., IJBNPA 2016.

    PubMed

    Humphreys, David K; Panter, Jenna; Ogilvie, David

    2017-04-19

    We recently read the article by Benton et al. which reviewed risk of bias in natural experimental studies investigating the impact of the built environment on physical activity (Benton et al., 2016; Int J Behav Nutr Phys Act 13:107). As a technical exercise in assessing risk of bias to understand study quality, we found the results of this study both interesting and potentially useful. However, it prompted a number of concerns with the use of risk of bias tools for assessing the quality of evidence from studies exploiting natural experiments. As we discuss in this commentary, the rigid application of such tools could have adverse effects on the uptake and use of natural experiments in population health research and practice.

  19. Computational Fluid Dynamics Simulation of Hydrodynamics and Stresses in the PhEur/USP Disintegration Tester Under Fed and Fasted Fluid Characteristics.

    PubMed

    Kindgen, Sarah; Wachtel, Herbert; Abrahamsson, Bertil; Langguth, Peter

    2015-09-01

    Disintegration of oral solid dosage forms is a prerequisite for drug dissolution and absorption and is to a large extent dependent on the pressures and hydrodynamic conditions in the solution that the dosage form is exposed to. In this work, the hydrodynamics in the PhEur/USP disintegration tester were investigated using computational fluid dynamics (CFD). Particle image velocimetry was used to validate the CFD predictions. The CFD simulations were performed with different Newtonian and non-Newtonian fluids, representing fasted and fed states. The results indicate that the current design and operating conditions of the disintegration test device, given by the pharmacopoeias, are not reproducing the in vivo situation. This holds true for the hydrodynamics in the disintegration tester that generates Reynolds numbers dissimilar to the reported in vivo situation. Also, when using homogenized US FDA meal, representing the fed state, too high viscosities and relative pressures are generated. The forces acting on the dosage form are too small for all fluids compared to the in vivo situation. The lack of peristaltic contractions, which generate hydrodynamics and shear stress in vivo, might be the major drawback of the compendial device resulting in the observed differences between predicted and in vivo measured hydrodynamics. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  20. ep→epπ0 reaction studied in the Δ(1232) mass region using polarization asymmetries

    NASA Astrophysics Data System (ADS)

    Biselli, A.; Adams, G. S.; Amaryan, M. J.; Anciant, E.; Anghinolfi, M.; Asavapibhop, B.; Asryan, G.; Audit, G.; Auger, T.; Avakian, H.; Barrow, S.; Battaglieri, M.; Beard, K.; Bektasoglu, M.; Bertozzi, W.; Bianchi, N.; Boiarinov, S.; Bonner, B. E.; Bosted, P.; Bouchigny, S.; Bradford, R.; Branford, D.; Brooks, W. K.; Bueltmann, S.; Burkert, V. D.; Calarco, J. R.; Carman, D. S.; Carnahan, B.; Cetina, C.; Ciciani, L.; Cole, P. L.; Coleman, A.; Connelly, J.; Cords, D.; Corvisiero, P.; Crabb, D.; Crannell, H.; Cummings, J.; de Sanctis, E.; de Vita, R.; Degtyarenko, P. V.; Demirchyan, R. A.; Denizli, H.; Dennis, L. C.; Dharmawardane, K. V.; Dhuga, K. S.; Djalali, C.; Dodge, G. E.; Domingo, J.; Doughty, D.; Dragovitsch, P.; Dugger, M.; Dytman, S.; Eckhause, M.; Efremenko, Y. V.; Egiyan, H.; Egiyan, K. S.; Elouadrhiri, L.; Empl, A.; Eugenio, P.; Farhi, L.; Fatemi, R.; Feuerbach, R. J.; Ficenec, J.; Fissum, K.; Forest, T. A.; Freyberger, A.; Frolov, V.; Funsten, H.; Gaff, S. J.; Gai, M.; Gavalian, G.; Gavrilov, V. B.; Gilad, S.; Gilfoyle, G. P.; Giovanetti, K. L.; Girard, P.; Golovatch, E.; Griffioen, K. A.; Guidal, M.; Guillo, M.; Guo, L.; Gyurjyan, V.; Hanock, D.; Hardie, J.; Heddle, D.; Hersman, F. W.; Hicks, K.; Hicks, R. S.; Holtrop, M.; Hu, J.; Hyde-Wright, C. E.; Ito, M. M.; Jenkins, D.; Joo, K.; Kelley, J. H.; Khandaker, M.; Kim, K. Y.; Kim, K.; Kim, W.; Klein, A.; Klein, F. J.; Klimenko, A. V.; Klusman, M.; Kossov, M.; Kramer, L. H.; Kuang, Y.; Kuhn, J.; Kuhn, S. E.; Lachniet, J.; Laget, J. M.; Lawrence, D.; Leksin, G. A.; Longhi, A.; Loukachine, K.; Major, R. W.; Manak, J. J.; Marchand, C.; Matthews, S. K.; McAleer, S.; McNabb, J. W.; McCarthy, J.; Mecking, B. A.; Mestayer, M. D.; Meyer, C. A.; Minehart, R.; Mirazita, M.; Miskimen, R.; Mokeev, V.; Muccifora, V.; Mueller, J.; Murphy, L. Y.; Mutchler, G. S.; Napolitano, J.; Nelson, S. O.; Niculescu, G.; Niczyporuk, B.; Niyazov, R. A.; Nozar, M.; O'Brien, J. T.; O'Rielly, G. V.; Ohandjanyan, M. S.; Osipenko, M.; Park, K.; Patois, Y.; Peterson, G. A.; Philips, S.; Pivnyuk, N.; Pocanic, D.; Pogorelko, O.; Polli, E.; Preedom, B. M.; Price, J. W.; Qin, L. M.; Raue, B. A.; Riccardi, G.; Ricco, G.; Ripani, M.; Ritchie, B. G.; Rock, S.; Ronchetti, F.; Rossi, P.; Rowntree, D.; Rubin, P. D.; Sabourov, K.; Salgado, C. W.; Sapunenko, V.; Sargsyan, M.; Schumacher, R. A.; Serov, V. S.; Sharabian, Y. G.; Shaw, J.; Shuvalov, S. M.; Simionatto, S.; Skabelin, A.; Smith, E. S.; Smith, L. C.; Smith, T.; Sober, D. I.; Sorrell, L.; Spraker, M.; Stepanyan, S.; Stoler, P.; Strakovsky, I. I.; Taiuti, M.; Taylor, S.; Tedeschi, D.; Thoma, U.; Thompson, R.; Todor, L.; Tung, T. Y.; Tur, C.; Ungaro, M.; Vineyard, M. F.; Vlassov, A.; Wang, K.; Weinstein, L. B.; Weller, H.; Welsh, R.; Weygand, D. P.; Whisnant, S.; Witkowski, M.; Wolin, E.; Yegneswaran, A.; Yun, J.; Zhang, B.; Zhao, J.; Zhou, Z.

    2003-09-01

    Measurements of the angular distributions of target and double-spin asymmetries for the Δ+(1232) in the exclusive channel p→(e→,e'p)π0 obtained at the Jefferson Lab in the Q2 range from 0.5 to 1.5 GeV2/c2 are presented. Results of the asymmetries are compared with the unitary isobar model [D. Drechsel et al., Nucl. Phys. A645, 145 (1999)], dynamical models [T. Sato and T. S. Lee, Phys. Rev. C 54, 2660 (1996); S. S. Kamalov et al., Phys. Lett. B 27, 522 (2001)], and the effective Lagrangian theory [R. M. Davidson et al., Phys. Rev. D 43, 71 (1991)]. Sensitivity to the different models was observed, particularly in relation to the description of background terms on which the target asymmetry depends significantly.

  1. Theoretical approach to the ground state of spherically confined Yukawa plasmas

    NASA Astrophysics Data System (ADS)

    Henning, Christian; Bonitz, Michael; Piel, Alexander; Ludwig, Patrick; Baumgartner, Henning

    2007-11-01

    Recently spherical 3D dust crystals (aka Yukawa balls) were discovered [1], which allow direct observation of strong correlation phenomena and the structure of which is well explained by computer simulations of charged Yukawa interacting particles within an external parabolic confinement [2]. Here we present an analytical approach to the ground state of these systems using the minimization of the system's energy. Applying the non-local mean-field approximation we show that screening has a dramatic effect on the density profile, which can be derived explicitly [3]. In addition the local density approximation allows for the inclusion of correlations, which further improves the results in the regime of large screening [4]. Comparisons with MD simulations of Yukawa balls show excellent agreement.[1] O. Arp et al. Phys. Rev. Lett. 93, 165004 (2004)[2] M. Bonitz et al., Phys. Rev. Lett. 96, 075001 (2006)[3] C. Henning et al., Phys. Rev. E 74, 056403 (2006)[4] C. Henning at al., Phys. Rev. E (2007)

  2. X-ray continuum as a measure of pressure and fuel–shell mix in compressed isobaric hydrogen implosion cores

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Epstein, R.; Goncharov, V. N.; Marshall, F. J.

    Pressure, by definition, characterizes the conditions within an isobaric implosion core at peak compression [Gus'kov et al., Nucl. Fusion 16, 957 (1976); Betti et al., Phys. Plasmas 8, 5257 (2001)] and is a key parameter in quantifying its near-ignition performance [Lawson, Proc. Phys. Soc. London, B 70, 6 (1957); Betti et al., Phys. Plasmas 17, 058102 (2010); Goncharov et al., Phys. Plasmas 21, 056315 (2014); and Glenzer et al., Phys. Plasmas 19, 056318 (2012)]. At high spectral energy, where the x-ray emission from an imploded hydrogen core is optically thin, the emissivity profile can be inferred from the spatially resolvedmore » core emission. This emissivity, which can be modeled accurately under hot-core conditions, is dependent almost entirely on the pressure when measured within a restricted spectral range matched to the temperature range anticipated for the emitting volume. In this way, the hot core pressure at the time of peak emission can be inferred from the measured free-free emissivity profile. The pressure and temperature dependences of the x-ray emissivity and the neutron-production rate explain a simple scaling of the total filtered x-ray emission as a constant power of the total neutron yield for implosions of targets of similar design over a broad range of shell implosion isentropes. This scaling behavior has been seen in implosion simulations and is confirmed by measurements of high-isentrope implosions [Sangster et al., Phys. Plasmas 20, 056317 (2013)] on the OMEGA laser system [Boehly et al., Opt. Commun. 133, 495 (1997)]. Attributing the excess emission from less-stable, low-isentrope implosions, above the level expected from this neutron-yield scaling, to the higher emissivity of shell carbon mixed into the implosion's central hot spot, the hot-spot “fuel–shell” mix mass can be inferred.« less

  3. X-ray continuum as a measure of pressure and fuel–shell mix in compressed isobaric hydrogen implosion cores

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Epstein, R.; Goncharov, V. N.; Marshall, F. J.

    Pressure, by definition, characterizes the conditions within an isobaric implosion core at peak compression [Gus’kov et al., Nucl. Fusion 16, 957 (1976); Betti et al., Phys. Plasmas 8, 5257 (2001)] and is a key parameter in quantifying its near-ignition performance [Lawson, Proc. Phys. Soc. London, B 70, 6 (1957); Betti et al., Phys. Plasmas 17, 058102 (2010); Goncharov et al., Phys. Plasmas 21, 056315 (2014); and Glenzer et al., Phys. Plasmas 19, 056318 (2012)]. At high spectral energy, where the x-ray emission from an imploded hydrogen core is optically thin, the emissivity profile can be inferred from the spatially resolvedmore » core emission. This emissivity, which can be modeled accurately under hot-core conditions, is dependent almost entirely on the pressure when measured within a restricted spectral range matched to the temperature range anticipated for the emitting volume. In this way, the hot core pressure at the time of peak emission can be inferred from the measured free-free emissivity profile. The pressure and temperature dependences of the x-ray emissivity and the neutron-production rate explain a simple scaling of the total filtered x-ray emission as a constant power of the total neutron yield for implosions of targets of similar design over a broad range of shell implosion isentropes. This scaling behavior has been seen in implosion simulations and is confirmed by measurements of high-isentrope implosions [Sangster et al., Phys. Plasmas 20, 056317 (2013)] on the OMEGA laser system [Boehly et al., Opt. Commun. 133, 495 (1997)]. Attributing the excess emission from less-stable, low-isentrope implosions, above the level expected from this neutron-yield scaling, to the higher emissivity of shell carbon mixed into the implosion’s central hot spot, the hot-spot “fuel–shell” mix mass can be inferred.« less

  4. Vibrational Surface Electron-Energy-Loss Spectroscopy Probes Confined Surface-Phonon Modes

    NASA Astrophysics Data System (ADS)

    Lourenço-Martins, Hugo; Kociak, Mathieu

    2017-10-01

    Recently, two reports [Krivanek et al. Nature (London) 514, 209 (2014), 10.1038/nature13870, Lagos et al. Nature (London) 543, 529 (2017), 10.1038/nature21699] have demonstrated the amazing possibility to probe vibrational excitations from nanoparticles with a spatial resolution much smaller than the corresponding free-space phonon wavelength using electron-energy-loss spectroscopy (EELS). While Lagos et al. evidenced a strong spatial and spectral modulation of the EELS signal over a nanoparticle, Krivanek et al. did not. Here, we show that discrepancies among different EELS experiments as well as their relation to optical near- and far-field optical experiments [Dai et al. Science 343, 1125 (2014), 10.1126/science.1246833] can be understood by introducing the concept of confined bright and dark surface phonon modes, whose density of states is probed by EELS. Such a concise formalism is the vibrational counterpart of the broadly used formalism for localized surface plasmons [Ouyang and Isaacson Philos. Mag. B 60, 481 (1989), 10.1080/13642818908205921, García de Abajo and Aizpurua Phys. Rev. B 56, 15873 (1997), 10.1103/PhysRevB.56.15873, García de Abajo and Kociak Phys. Rev. Lett. 100, 106804 (2008), 10.1103/PhysRevLett.100.106804, Boudarham and Kociak Phys. Rev. B 85, 245447 (2012), 10.1103/PhysRevB.85.245447]; it makes it straightforward to predict or interpret phenomena already known for localized surface plasmons such as environment-related energy shifts or the possibility of 3D mapping of the related surface charge densities [Collins et al. ACS Photonics 2, 1628 (2015), 10.1021/acsphotonics.5b00421].

  5. Phys FilmMakers: teaching science students how to make YouTube-style videos

    NASA Astrophysics Data System (ADS)

    Coates, Rebecca L.; Kuhai, Alvina; Turlej, Laurence Z. J.; Rivlin, Tom; McKemmish, Laura K.

    2018-01-01

    Phys FilmMakers (PFM) is a new type of course in which a science expert and science communicator partner teach physics students how to make YouTube-style videos on cutting-edge scientific research within the university department. Here, we describe this new course, outline its key components and provide recommendations for others considering implementing a similar FilmMakers-style course using feedback from course tutors and students. We discuss successful and less successful teaching techniques as well as use our experience to identify areas that science students in particular often have difficulties: finding an interesting ‘hook’ for the video, imagining creative B-roll and making a succinct video by removing extraneous (though usually correct and often interesting) material. The course has two major components: workshop sessions in which students learn the key elements of film-making and independent video production where PFM students partner with senior PhD or post-doc researchers to produce a video on their research. This partnership with the department means that the videos produced serve not only as interesting ‘edutainment’ to encourage teenagers and young adults into Science, Technology, Engineering and Maths subjects, but also provide valuable outreach for the academic department.

  6. Cryptanalysis and Improvement of the Semi-quantum Secret Sharing Protocol

    NASA Astrophysics Data System (ADS)

    Gao, Xiang; Zhang, Shibin; Chang, Yan

    2017-08-01

    Recently, Xie et al. Int. J. Theor. Phys. 54, 3819-3824, (2015) proposed a Semi-quantum secret sharing protocol (SQSS). Yin et al. Int. J. Theor. Phys. 55: 4027-4035, (2016) pointed out that this protocol suffers from the intercept-resend attack. Yin et al. also proposed an improved protocol. However, we find out that Yin et al.'s paper has some problems, we analyze Yin et al.'s paper, then proposed the improved semi-quantum secret sharing protocol. Our protocol is more secure and efficient, most importantly, our protocol satisfies the condition of semi-quantum.

  7. Greens Function-Based Defect Identification in InAs-InA1-xSbx Strained Layer Superlattices (Postprint)

    DTIC Science & Technology

    2017-06-15

    the GaSb valance band edge, in agreement with values deduced recently from lifetime measurements and analysis [Aytac et al . Phys. Rev. Appl., 5...meV below the GaSb valance band edge, in agreement with values deduced recently from lifetime mea- surements and analysis [Aytac et al . Phys. Rev

  8. Exploratory study of fission product yields of neutron-induced fission of 235U , 238U , and 239Pu at 8.9 MeV

    NASA Astrophysics Data System (ADS)

    Bhatia, C.; Fallin, B. F.; Gooden, M. E.; Howell, C. R.; Kelley, J. H.; Tornow, W.; Arnold, C. W.; Bond, E.; Bredeweg, T. A.; Fowler, M. M.; Moody, W.; Rundberg, R. S.; Rusev, G. Y.; Vieira, D. J.; Wilhelmy, J. B.; Becker, J. A.; Macri, R.; Ryan, C.; Sheets, S. A.; Stoyer, M. A.; Tonchev, A. P.

    2015-06-01

    Using dual-fission chambers each loaded with a thick (200 -400 -mg /c m2) actinide target of 235 ,238U or 239Pu and two thin (˜10 -100 -μ g /c m2) reference foils of the same actinide, the cumulative yields of fission products ranging from 92Sr to 147Nd have been measured at En= 8.9 MeV . The 2H(d ,n ) 3He reaction provided the quasimonoenergetic neutron beam. The experimental setup and methods used to determine the fission product yield (FPY) are described, and results for typically eight high-yield fission products are presented. Our FPYs for 235U(n ,f ) , 238U(n ,f ) , and 239Pu(n ,f ) at 8.9 MeV are compared with the existing data below 8 MeV from Glendenin et al. [Phys. Rev. C 24, 2600 (1981), 10.1103/PhysRevC.24.2600], Nagy et al. [Phys. Rev. C 17, 163 (1978), 10.1103/PhysRevC.17.163], Gindler et al. [Phys. Rev. C 27, 2058 (1983), 10.1103/PhysRevC.27.2058], and those of Mac Innes et al. [Nucl. Data Sheets 112, 3135 (2011), 10.1016/j.nds.2011.11.009] and Laurec et al. [Nucl. Data Sheets 111, 2965 (2010), 10.1016/j.nds.2010.11.004] at 14.5 and 14.7 MeV, respectively. This comparison indicates a negative slope for the energy dependence of most fission product yields obtained from 235U and 239Pu , whereas for 238U the slope issue remains unsettled.

  9. Influence of the parallel nonlinearity on zonal flows and heat transport in global gyrokinetic particle-in-cell simulations

    NASA Astrophysics Data System (ADS)

    Jolliet, S.; McMillan, B. F.; Vernay, T.; Villard, L.; Hatzky, R.; Bottino, A.; Angelino, P.

    2009-07-01

    In this paper, the influence of the parallel nonlinearity on zonal flows and heat transport in global particle-in-cell ion-temperature-gradient simulations is studied. Although this term is in theory orders of magnitude smaller than the others, several authors [L. Villard, P. Angelino, A. Bottino et al., Plasma Phys. Contr. Fusion 46, B51 (2004); L. Villard, S. J. Allfrey, A. Bottino et al., Nucl. Fusion 44, 172 (2004); J. C. Kniep, J. N. G. Leboeuf, and V. C. Decyck, Comput. Phys. Commun. 164, 98 (2004); J. Candy, R. E. Waltz, S. E. Parker et al., Phys. Plasmas 13, 074501 (2006)] found different results on its role. The study is performed using the global gyrokinetic particle-in-cell codes TORB (theta-pinch) [R. Hatzky, T. M. Tran, A. Könies et al., Phys. Plasmas 9, 898 (2002)] and ORB5 (tokamak geometry) [S. Jolliet, A. Bottino, P. Angelino et al., Comput. Phys. Commun. 177, 409 (2007)]. In particular, it is demonstrated that the parallel nonlinearity, while important for energy conservation, affects the zonal electric field only if the simulation is noise dominated. When a proper convergence is reached, the influence of parallel nonlinearity on the zonal electric field, if any, is shown to be small for both the cases of decaying and driven turbulence.

  10. Comment on "Many-body localization in Ising models with random long-range interactions"

    NASA Astrophysics Data System (ADS)

    Maksymov, Andrii O.; Rahman, Noah; Kapit, Eliot; Burin, Alexander L.

    2017-11-01

    This Comment is dedicated to the investigation of many-body localization in a quantum Ising model with long-range power-law interactions r-α, relevant for a variety of systems ranging from electrons in Anderson insulators to spin excitations in chains of cold atoms. It has earlier been argued [arXiv:cond-mat/0611387 (2005); Phys. Rev. B 91, 094202 (2015), 10.1103/PhysRevB.91.094202] that this model obeys the dimensional constraint suggesting the delocalization of all finite-temperature states in the thermodynamic limit for α ≤2 d in a d -dimensional system. This expectation conflicts with the recent numerical studies of the specific interacting spin model of Li et al. [Phys. Rev. A 94, 063625 (2016), 10.1103/PhysRevA.94.063625]. To resolve this controversy we reexamine the model of Li et al. [Phys. Rev. A 94, 063625 (2016), 10.1103/PhysRevA.94.063625] and demonstrate that the infinite-temperature states there obey the dimensional constraint. The earlier developed scaling theory for the critical system size required for delocalization is extended to small exponents 0 ≤α ≤d . The disagreements between the two works are explained by the nonstandard selection of investigated states in the ordered phase in the work of Li et al. [Phys. Rev. A 94, 063625 (2016)10.1103/PhysRevA.94.063625].

  11. Ethical violations and discriminatory behavior in the MedPhys Match.

    PubMed

    Hendrickson, Kristi R G; Juang, Titania; Rodrigues, Anna; Burmeister, Jay W

    2017-09-01

    The purpose of this survey study is to investigate behaviors in conflict with the ethical standards of the Medical Physics Residency (MedPhys) Match (MPM) process as stated in the MPM rules (a) and with the nondiscrimination regulations of the Equal Employment Opportunity Commission (EEOC) (b), in addition to other behaviors that may in other ways erode the fairness of the system. A survey was sent to all applicants and program directors registered for the 2015 and 2016 MPM. Survey questions asked about application, interview, and postinterview experiences, match results, and overall satisfaction with the process. Thirteen percent of 2015 respondents and 20% of 2016 respondents were asked by at least one program how highly they planned to rank them or which program they would rank first. Thirty-seven percent of 2015 and 40% of 2016 program directors indicated that candidates communicated to the program their rank intent, with 22.0% in 2015 and 12.5% in 2016 being told that their program would be ranked first. Twenty-three percent of 2015 respondents indicated being asked by at least one program during the interview about children or plans to have children; including 19% of males and 33% of females. In 2016, these values were 28% overall, 22% male, and 36% female. Fifty-seven percent of 2015 respondents who were asked this question indicated being uncomfortable or very uncomfortable answering, including 27.3% of males and 88.9% of females. In 2016, 42.9% of all respondents indicated being uncomfortable or very uncomfortable answering, including 10.0% of males and 80.0% of females. In the first two years of the MPM, there were widespread instances of ethical violations and discriminatory questioning during the interview process. Educating both interviewers and candidates on the MPM rules and general EEOC guidelines should decrease these instances and increase the fairness of the residency selection process. © 2017 The Authors. Journal of Applied Clinical Medical

  12. Wireless Telemetry of In-Flight Collision Avoidance Neural Signals in Insects

    DTIC Science & Technology

    2010-09-01

    with a high LQ product, along with vertical npn transistors (Q1 and Q2) providing a high gm/I ratio with relatively low parasitic capacitance allows...species (pigeon: Sun and Frost, 1998; frog: Kang and Nakagawa, 2006; fish : Preuss et al., 2006; fruit fly: Fotowat et al., 2009). In locusts, this...Eur. J. Neurosci. 7, 981-992. Houweling, A. R. and Brecht, M. (2008). Behavioural report of single neuron stimulation in somatosensory cortex

  13. Compact Magnetic Antennas for Directional Excitation of Surface Plasmons

    DTIC Science & Technology

    2012-07-01

    Steininger, G.; Koch, M.; von Plessen, G.; Feldmann, J. Launching surface plasmons into nanoholes in metal films. Appl. Phys. Lett. 2000, 76, 140−142...plasmons at single nanoholes in Au films. Appl. Phys. Lett. 2004, 85, 467−469. (14) Baudrion, A.-L.; et al. Coupling efficiency of light to surface

  14. Relativistic corrections to the ground state of H2 calculated without using the Born-Oppenheimer approximation

    NASA Astrophysics Data System (ADS)

    Wang, L. M.; Yan, Z.-C.

    2018-06-01

    The Schrödinger equation for the ground state of the hydrogen molecule H2 is solved by applying the Rayleigh-Ritz variational method in Hylleraas coordinates without using the Born-Oppenheimer approximation. The nonrelativistic energy eigenvalue is converged to -1.164 025 030 880 (7 ) atomic units. The leading-order relativistic corrections, including the mass-velocity, Darwin, orbit-orbit, spin-spin, and relativistic recoil terms, are evaluated perturbatively. Together with the higher-order relativistic and quantum electrodynamic corrections obtained by Puchalski et al. [Phys. Rev. Lett. 117, 263002 (2016), 10.1103/PhysRevLett.117.263002], we determine the dissociation energy of the hydrogen molecule, D0=36 118.069 71 (33 ) cm-1 , which agrees with the two recent experimental results of Liu et al. [J. Chem. Phys. 130, 174306 (2009), 10.1063/1.3120443], 36 118.069 62 (37 ) cm-1 , and Altmann et al. [Phys. Rev. Lett. 120, 043204 (2018), 10.1103/PhysRevLett.120.043204], 36 118.069 45 (31 ) cm-1 .

  15. Luminescence and luminescence quenching in Gd3(Ga,Al)5O12 scintillators doped with Ce3+.

    PubMed

    Ogiegło, Joanna M; Katelnikovas, Arturas; Zych, Aleksander; Jüstel, Thomas; Meijerink, Andries; Ronda, Cees R

    2013-03-28

    The optical properties of gadolinium gallium aluminum garnet, Gd3(Ga,Al)5O12, doped with Ce(3+) are investigated as a function of the Ga/Al ratio, aimed at an improved understanding of the energy flow and luminescence quenching in these materials. A decrease of both the crystal field strength and band gap with increasing content of Ga(3+) is observed and explained by the geometrical influence of Ga(3+) on the crystal field splitting of the 5d level in line with theoretical work of Muñoz-García et al. ( uñoz-García, A. B.; Seijo, L. Phys. Rev. B 2010, 82, 184118 ). Thermal quenching results in shorter decay times as well as reduced emission intensities for all samples in the temperature range from 100 to 500 K. An activation energy for emission quenching is calculated from the data. The band gap of the host is measured upon Ga substitution and the decrease in band gap is related to Ga(3+) substitution into tetrahedral sites after all octahedral sites are occupied in the garnet material. Based on the change in band gap and crystal field splitting, band diagrams can be constructed explaining the low thermal quenching temperatures in the samples with high Ga content. The highest luminescence intensity is found for Gd3(Ga,Al)5O12 with 40% of Al(3+) replaced by Ga(3+).

  16. Relativistically induced transparency acceleration of light ions by an ultrashort laser pulse interacting with a heavy-ion-plasma density gradient.

    PubMed

    Sahai, Aakash A; Tsung, Frank S; Tableman, Adam R; Mori, Warren B; Katsouleas, Thomas C

    2013-10-01

    The relativistically induced transparency acceleration (RITA) scheme of proton and ion acceleration using laser-plasma interactions is introduced, modeled, and compared to the existing schemes. Protons are accelerated with femtosecond relativistic pulses to produce quasimonoenergetic bunches with controllable peak energy. The RITA scheme works by a relativistic laser inducing transparency [Akhiezer and Polovin, Zh. Eksp. Teor. Fiz 30, 915 (1956); Kaw and Dawson, Phys. Fluids 13, 472 (1970); Max and Perkins, Phys. Rev. Lett. 27, 1342 (1971)] to densities higher than the cold-electron critical density, while the background heavy ions are stationary. The rising laser pulse creates a traveling acceleration structure at the relativistic critical density by ponderomotively [Lindl and Kaw, Phys. Fluids 14, 371 (1971); Silva et al., Phys. Rev. E 59, 2273 (1999)] driving a local electron density inflation, creating an electron snowplow and a co-propagating electrostatic potential. The snowplow advances with a velocity determined by the rate of the rise of the laser's intensity envelope and the heavy-ion-plasma density gradient scale length. The rising laser is incrementally rendered transparent to higher densities such that the relativistic-electron plasma frequency is resonant with the laser frequency. In the snowplow frame, trace density protons reflect off the electrostatic potential and get snowplowed, while the heavier background ions are relatively unperturbed. Quasimonoenergetic bunches of velocity equal to twice the snowplow velocity can be obtained and tuned by controlling the snowplow velocity using laser-plasma parameters. An analytical model for the proton energy as a function of laser intensity, rise time, and plasma density gradient is developed and compared to 1D and 2D PIC OSIRIS [Fonseca et al., Lect. Note Comput. Sci. 2331, 342 (2002)] simulations. We model the acceleration of protons to GeV energies with tens-of-femtoseconds laser pulses of a few

  17. Quasi-additive estimates on the Hamiltonian for the one-dimensional long range Ising model

    NASA Astrophysics Data System (ADS)

    Littin, Jorge; Picco, Pierre

    2017-07-01

    In this work, we study the problem of getting quasi-additive bounds for the Hamiltonian of the long range Ising model, when the two-body interaction term decays proportionally to 1/d2 -α , α ∈(0,1 ) . We revisit the paper by Cassandro et al. [J. Math. Phys. 46, 053305 (2005)] where they extend to the case α ∈[0 ,ln3/ln2 -1 ) the result of the existence of a phase transition by using a Peierls argument given by Fröhlich and Spencer [Commun. Math. Phys. 84, 87-101 (1982)] for α =0 . The main arguments of Cassandro et al. [J. Math. Phys. 46, 053305 (2005)] are based in a quasi-additive decomposition of the Hamiltonian in terms of hierarchical structures called triangles and contours, which are related to the original definition of contours introduced by Fröhlich and Spencer [Commun. Math. Phys. 84, 87-101 (1982)]. In this work, we study the existence of a quasi-additive decomposition of the Hamiltonian in terms of the contours defined in the work of Cassandro et al. [J. Math. Phys. 46, 053305 (2005)]. The most relevant result obtained is Theorem 4.3 where we show that there is a quasi-additive decomposition for the Hamiltonian in terms of contours when α ∈[0,1 ) but not in terms of triangles. The fact that it cannot be a quasi-additive bound in terms of triangles lead to a very interesting maximization problem whose maximizer is related to a discrete Cantor set. As a consequence of the quasi-additive bounds, we prove that we can generalise the [Cassandro et al., J. Math. Phys. 46, 053305 (2005)] result, that is, a Peierls argument, to the whole interval α ∈[0,1 ) . We also state here the result of Cassandro et al. [Commun. Math. Phys. 327, 951-991 (2014)] about cluster expansions which implies that Theorem 2.4 that concerns interfaces and Theorem 2.5 that concerns n point truncated correlation functions in Cassandro et al. [Commun. Math. Phys. 327, 951-991 (2014)] are valid for all α ∈[0,1 ) instead of only α ∈[0 ,ln3/ln2 -1 ) .

  18. Doping effect on charge ordering in the spinel compound AlV_2-xCr_xO_4

    NASA Astrophysics Data System (ADS)

    Horibe, Yoichi; Kurushima, Kosuke; Mori, Shigeo; Shingu, Masao; Katsufuji, Takuro

    2004-03-01

    It is reported that AlV_2O4 with the spinel-type structure shows the charge-ordering (CO) behavior below 700K.[1] Because the average valence of V is V^2.5+ in this compound, the CO structure is characterized by the unique CO pattern with V^2+:V^4+=3:1. In this talk, we will report doping effect on the CO structure in AlV_2O_4. In particular, we will focus on changes of microstructure related to the CO structure by Cr doping by transmission electron microscopy. Firstly we confirmed that AlV_2O4 has a long-ranged CO structure characterized by a single wave vector q=(1/2)[111]. On the other hand, we found the presence of diffuse scatterings at the (1/2)[111] and (1/2)[1-11]-type positions in AlV_1.875Cr_0.125O4 at room temperature. This means that the CO structure in AlV_1.875Cr_0.125O4 has two wave vectors of q=(1/2)[111] and q=the (1/2)[1-11]. Furthermore, the long-ranged CO structure in AlV_2O4 changes into the short-ranged one by substituting Cr ions into the V ones. The correlation length of CO in x=0.125 can be estimated to be about 5 nm. Our results suggest that the Cr doping destroyed the CO correlation effectively. It is revealed that by substituting Cr ions to V ones, the CO state is suppressed drastically and disappeared with x > 0.125. [1] K. Matsuno et al., J. Phys. Soc. Jpn 70, 1456 (2001)

  19. The Physics of the B Factories

    NASA Astrophysics Data System (ADS)

    Bevan, A. J.; Golob, B.; Mannel, Th.; Prell, S.; Yabsley, B. D.; Aihara, H.; Anulli, F.; Arnaud, N.; Aushev, T.; Beneke, M.; Beringer, J.; Bianchi, F.; Bigi, I. I.; Bona, M.; Brambilla, N.; Brodzicka, J.; Chang, P.; Charles, M. J.; Cheng, C. H.; Cheng, H.-Y.; Chistov, R.; Colangelo, P.; Coleman, J. P.; Drutskoy, A.; Druzhinin, V. P.; Eidelman, S.; Eigen, G.; Eisner, A. M.; Faccini, R.; Flood, K. T.; Gambino, P.; Gaz, A.; Gradl, W.; Hayashii, H.; Higuchi, T.; Hulsbergen, W. D.; Hurth, T.; Iijima, T.; Itoh, R.; Jackson, P. D.; Kass, R.; Kolomensky, Yu. G.; Kou, E.; Križan, P.; Kronfeld, A.; Kumano, S.; Kwon, Y. J.; Latham, T. E.; Leith, D. W. G. S.; Lüth, V.; Martinez-Vidal, F.; Meadows, B. T.; Mussa, R.; Nakao, M.; Nishida, S.; Ocariz, J.; Olsen, S. L.; Pakhlov, P.; Pakhlova, G.; Palano, A.; Pich, A.; Playfer, S.; Poluektov, A.; Porter, F. C.; Robertson, S. H.; Roney, J. M.; Roodman, A.; Sakai, Y.; Schwanda, C.; Schwartz, A. J.; Seidl, R.; Sekula, S. J.; Steinhauser, M.; Sumisawa, K.; Swanson, E. S.; Tackmann, F.; Trabelsi, K.; Uehara, S.; Uno, S.; van de Water, R.; Vasseur, G.; Verkerke, W.; Waldi, R.; Wang, M. Z.; Wilson, F. F.; Zupan, J.; Zupanc, A.; Adachi, I.; Albert, J.; Banerjee, Sw.; Bellis, M.; Ben-Haim, E.; Biassoni, P.; Cahn, R. N.; Cartaro, C.; Chauveau, J.; Chen, C.; Chiang, C. C.; Cowan, R.; Dalseno, J.; Davier, M.; Davies, C.; Dingfelder, J. C.; Echenard, B.; Epifanov, D.; Fulsom, B. G.; Gabareen, A. M.; Gary, J. W.; Godang, R.; Graham, M. T.; Hafner, A.; Hamilton, B.; Hartmann, T.; Hayasaka, K.; Hearty, C.; Iwasaki, Y.; Khodjamirian, A.; Kusaka, A.; Kuzmin, A.; Lafferty, G. D.; Lazzaro, A.; Li, J.; Lindemann, D.; Long, O.; Lusiani, A.; Marchiori, G.; Martinelli, M.; Miyabayashi, K.; Mizuk, R.; Mohanty, G. B.; Muller, D. R.; Nakazawa, H.; Ongmongkolkul, P.; Pacetti, S.; Palombo, F.; Pedlar, T. K.; Piilonen, L. E.; Pilloni, A.; Poireau, V.; Prothmann, K.; Pulliam, T.; Rama, M.; Ratcliff, B. N.; Roudeau, P.; Schrenk, S.; Schroeder, T.; Schubert, K. R.; Shen, C. P.; Shwartz, B.; Soffer, A.; Solodov, E. P.; Somov, A.; Starič, M.; Stracka, S.; Telnov, A. V.; Todyshev, K. Yu.; Tsuboyama, T.; Uglov, T.; Vinokurova, A.; Walsh, J. J.; Watanabe, Y.; Won, E.; Wormser, G.; Wright, D. H.; Ye, S.; Zhang, C. C.; Abachi, S.; Abashian, A.; Abe, K.; Abe, N.; Abe, R.; Abe, T.; Abrams, G. S.; Adam, I.; Adamczyk, K.; Adametz, A.; Adye, T.; Agarwal, A.; Ahmed, H.; Ahmed, M.; Ahmed, S.; Ahn, B. S.; Ahn, H. S.; Aitchison, I. J. R.; Akai, K.; Akar, S.; Akatsu, M.; Akemoto, M.; Akhmetshin, R.; Akre, R.; Alam, M. S.; Albert, J. N.; Aleksan, R.; Alexander, J. P.; Alimonti, G.; Allen, M. T.; Allison, J.; Allmendinger, T.; Alsmiller, J. R. G.; Altenburg, D.; Alwyn, K. E.; An, Q.; Anderson, J.; Andreassen, R.; Andreotti, D.; Andreotti, M.; Andress, J. C.; Angelini, C.; Anipko, D.; Anjomshoaa, A.; Anthony, P. L.; Antillon, E. A.; Antonioli, E.; Aoki, K.; Arguin, J. F.; Arinstein, K.; Arisaka, K.; Asai, K.; Asai, M.; Asano, Y.; Asgeirsson, D. J.; Asner, D. M.; Aso, T.; Aspinwall, M. L.; Aston, D.; Atmacan, H.; Aubert, B.; Aulchenko, V.; Ayad, R.; Azemoon, T.; Aziz, T.; Azzolini, V.; Azzopardi, D. E.; Baak, M. A.; Back, J. J.; Bagnasco, S.; Bahinipati, S.; Bailey, D. S.; Bailey, S.; Bailly, P.; van Bakel, N.; Bakich, A. M.; Bala, A.; Balagura, V.; Baldini-Ferroli, R.; Ban, Y.; Banas, E.; Band, H. R.; Banerjee, S.; Baracchini, E.; Barate, R.; Barberio, E.; Barbero, M.; Bard, D. J.; Barillari, T.; Barlow, N. R.; Barlow, R. J.; Barrett, M.; Bartel, W.; Bartelt, J.; Bartoldus, R.; Batignani, G.; Battaglia, M.; Bauer, J. M.; Bay, A.; Beaulieu, M.; Bechtle, P.; Beck, T. W.; Becker, J.; Becla, J.; Bedny, I.; Behari, S.; Behera, P. K.; Behn, E.; Behr, L.; Beigbeder, C.; Beiline, D.; Bell, R.; Bellini, F.; Bellodi, G.; Belous, K.; Benayoun, M.; Benelli, G.; Benitez, J. F.; Benkebil, M.; Berger, N.; Bernabeu, J.; Bernard, D.; Bernet, R.; Bernlochner, F. U.; Berryhill, J. W.; Bertsche, K.; Besson, P.; Best, D. S.; Bettarini, S.; Bettoni, D.; Bhardwaj, V.; Bhimji, W.; Bhuyan, B.; Biagini, M. E.; Biasini, M.; van Bibber, K.; Biesiada, J.; Bingham, I.; Bionta, R. M.; Bischofberger, M.; Bitenc, U.; Bizjak, I.; Blanc, F.; Blaylock, G.; Blinov, V. E.; Bloom, E.; Bloom, P. C.; Blount, N. L.; Blouw, J.; Bly, M.; Blyth, S.; Boeheim, C. T.; Bomben, M.; Bondar, A.; Bondioli, M.; Bonneaud, G. R.; Bonvicini, G.; Booke, M.; Booth, J.; Borean, C.; Borgland, A. W.; Borsato, E.; Bosi, F.; Bosisio, L.; Botov, A. A.; Bougher, J.; Bouldin, K.; Bourgeois, P.; Boutigny, D.; Bowerman, D. A.; Boyarski, A. M.; Boyce, R. F.; Boyd, J. T.; Bozek, A.; Bozzi, C.; Bračko, M.; Brandenburg, G.; Brandt, T.; Brau, B.; Brau, J.; Breon, A. B.; Breton, D.; Brew, C.; Briand, H.; Bright-Thomas, P. G.; Brigljević, V.; Britton, D. I.; Brochard, F.; Broomer, B.; Brose, J.; Browder, T. E.; Brown, C. L.; Brown, C. M.; Brown, D. N.; Browne, M.; Bruinsma, M.; Brunet, S.; Bucci, F.; Buchanan, C.; Buchmueller, O. L.; Bünger, C.; Bugg, W.; Bukin, A. D.; Bula, R.; Bulten, H.; Burchat, P. R.; Burgess, W.; Burke, J. P.; Button-Shafer, J.; Buzykaev, A. R.; Buzzo, A.; Cai, Y.; Calabrese, R.; Calcaterra, A.; Calderini, G.; Camanzi, B.; Campagna, E.; Campagnari, C.; Capra, R.; Carassiti, V.; Carpinelli, M.; Carroll, M.; Casarosa, G.; Casey, B. C. K.; Cason, N. M.; Castelli, G.; Cavallo, N.; Cavoto, G.; Cecchi, A.; Cenci, R.; Cerizza, G.; Cervelli, A.; Ceseracciu, A.; Chai, X.; Chaisanguanthum, K. S.; Chang, M. C.; Chang, Y. H.; Chang, Y. W.; Chao, D. S.; Chao, M.; Chao, Y.; Charles, E.; Chavez, C. A.; Cheaib, R.; Chekelian, V.; Chen, A.; Chen, E.; Chen, G. P.; Chen, H. F.; Chen, J.-H.; Chen, J. C.; Chen, K. F.; Chen, P.; Chen, S.; Chen, W. T.; Chen, X.; Chen, X. R.; Chen, Y. Q.; Cheng, B.; Cheon, B. G.; Chevalier, N.; Chia, Y. M.; Chidzik, S.; Chilikin, K.; Chistiakova, M. V.; Cizeron, R.; Cho, I. S.; Cho, K.; Chobanova, V.; Choi, H. H. F.; Choi, K. S.; Choi, S. K.; Choi, Y.; Choi, Y. K.; Christ, S.; Chu, P. H.; Chun, S.; Chuvikov, A.; Cibinetto, G.; Cinabro, D.; Clark, A. R.; Clark, P. J.; Clarke, C. K.; Claus, R.; Claxton, B.; Clifton, Z. C.; Cochran, J.; Cohen-Tanugi, J.; Cohn, H.; Colberg, T.; Cole, S.; Colecchia, F.; Condurache, C.; Contri, R.; Convert, P.; Convery, M. R.; Cooke, P.; Copty, N.; Cormack, C. M.; Dal Corso, F.; Corwin, L. A.; Cossutti, F.; Cote, D.; Cotta Ramusino, A.; Cottingham, W. N.; Couderc, F.; Coupal, D. P.; Covarelli, R.; Cowan, G.; Craddock, W. W.; Crane, G.; Crawley, H. B.; Cremaldi, L.; Crescente, A.; Cristinziani, M.; Crnkovic, J.; Crosetti, G.; Cuhadar-Donszelmann, T.; Cunha, A.; Curry, S.; D'Orazio, A.; Dû, S.; Dahlinger, G.; Dahmes, B.; Dallapiccola, C.; Danielson, N.; Danilov, M.; Das, A.; Dash, M.; Dasu, S.; Datta, M.; Daudo, F.; Dauncey, P. D.; David, P.; Davis, C. L.; Day, C. T.; De Mori, F.; De Domenico, G.; De Groot, N.; De la Vaissière, C.; de la Vaissière, Ch.; de Lesquen, A.; De Nardo, G.; de Sangro, R.; De Silva, A.; DeBarger, S.; Decker, F. J.; del Amo Sanchez, P.; Del Buono, L.; Del Gamba, V.; del Re, D.; Della Ricca, G.; Denig, A. G.; Derkach, D.; Derrington, I. M.; DeStaebler, H.; Destree, J.; Devmal, S.; Dey, B.; Di Girolamo, B.; Marco, E. Di; Dickopp, M.; Dima, M. O.; Dittrich, S.; Dittongo, S.; Dixon, P.; Dneprovsky, L.; Dohou, F.; Doi, Y.; Doležal, Z.; Doll, D. A.; Donald, M.; Dong, L.; Dong, L. Y.; Dorfan, J.; Dorigo, A.; Dorsten, M. P.; Dowd, R.; Dowdell, J.; Drásal, Z.; Dragic, J.; Drummond, B. W.; Dubitzky, R. S.; Dubois-Felsmann, G. P.; Dubrovin, M. S.; Duh, Y. C.; Duh, Y. T.; Dujmic, D.; Dungel, W.; Dunwoodie, W.; Dutta, D.; Dvoretskii, A.; Dyce, N.; Ebert, M.; Eckhart, E. A.; Ecklund, S.; Eckmann, R.; Eckstein, P.; Edgar, C. L.; Edwards, A. J.; Egede, U.; Eichenbaum, A. M.; Elmer, P.; Emery, S.; Enari, Y.; Enomoto, R.; Erdos, E.; Erickson, R.; Ernst, J. A.; Erwin, R. J.; Escalier, M.; Eschenburg, V.; Eschrich, I.; Esen, S.; Esteve, L.; Evangelisti, F.; Everton, C. W.; Eyges, V.; Fabby, C.; Fabozzi, F.; Fahey, S.; Falbo, M.; Fan, S.; Fang, F.; Fanin, C.; Farbin, A.; Farhat, H.; Fast, J. E.; Feindt, M.; Fella, A.; Feltresi, E.; Ferber, T.; Fernholz, R. E.; Ferrag, S.; Ferrarotto, F.; Ferroni, F.; Field, R. C.; Filippi, A.; Finocchiaro, G.; Fioravanti, E.; Firmino da Costa, J.; Fischer, P.-A.; Fisher, A. S.; Fisher, P. H.; Flacco, C. J.; Flack, R. L.; Flaecher, H. U.; Flanagan, J.; Flanigan, J. M.; Ford, K. E.; Ford, W. T.; Forster, I. J.; Forti, A. C.; Forti, F.; Fortin, D.; Foster, B.; Foulkes, S. D.; Fouque, G.; Fox, J.; Franchini, P.; Franco Sevilla, M.; Franek, B.; Frank, E. D.; Fransham, K. B.; Fratina, S.; Fratini, K.; Frey, A.; Frey, R.; Friedl, M.; Fritsch, M.; Fry, J. R.; Fujii, H.; Fujikawa, M.; Fujita, Y.; Fujiyama, Y.; Fukunaga, C.; Fukushima, M.; Fullwood, J.; Funahashi, Y.; Funakoshi, Y.; Furano, F.; Furman, M.; Furukawa, K.; Futterschneider, H.; Gabathuler, E.; Gabriel, T. A.; Gabyshev, N.; Gaede, F.; Gagliardi, N.; Gaidot, A.; Gaillard, J.-M.; Gaillard, J. R.; Galagedera, S.; Galeazzi, F.; Gallo, F.; Gamba, D.; Gamet, R.; Gan, K. K.; Gandini, P.; Ganguly, S.; Ganzhur, S. F.; Gao, Y. Y.; Gaponenko, I.; Garmash, A.; Garra Tico, J.; Garzia, I.; Gaspero, M.; Gastaldi, F.; Gatto, C.; Gaur, V.; Geddes, N. I.; Geld, T. L.; Genat, J.-F.; George, K. A.; George, M.; George, S.; Georgette, Z.; Gershon, T. J.; Gill, M. S.; Gillard, R.; Gilman, J. D.; Giordano, F.; Giorgi, M. A.; Giraud, P.-F.; Gladney, L.; Glanzman, T.; Glattauer, R.; Go, A.; Goetzen, K.; Goh, Y. M.; Gokhroo, G.; Goldenzweig, P.; Golubev, V. B.; Gopal, G. P.; Gordon, A.; Gorišek, A.; Goriletsky, V. I.; Gorodeisky, R.; Gosset, L.; Gotow, K.; Gowdy, S. J.; Graffin, P.; Grancagnolo, S.; Grauges, E.; Graziani, G.; Green, M. G.; Greene, M. G.; Grenier, G. J.; Grenier, P.; Griessinger, K.; Grillo, A. A.; Grinyov, B. V.; Gritsan, A. V.; Grosdidier, G.; Grosse Perdekamp, M.; Grosso, P.; Grothe, M.; Groysman, Y.; Grünberg, O.; Guido, E.; Guler, H.; Gunawardane, N. J. W.; Guo, Q. H.; Guo, R. S.; Guo, Z. J.; Guttman, N.; Ha, H.; Ha, H. C.; Haas, T.; Haba, J.; Hachtel, J.; Hadavand, H. K.; Hadig, T.; Hagner, C.; Haire, M.; Haitani, F.; Haji, T.; Haller, G.; Halyo, V.; Hamano, K.; Hamasaki, H.; Hamel de Monchenault, G.; Hamilton, J.; Hamilton, R.; Hamon, O.; Han, B. Y.; Han, Y. L.; Hanada, H.; Hanagaki, K.; Handa, F.; Hanson, J. E.; Hanushevsky, A.; Hara, K.; Hara, T.; Harada, Y.; Harrison, P. F.; Harrison, T. J.; Harrop, B.; Hart, A. J.; Hart, P. A.; Hartfiel, B. L.; Harton, J. L.; Haruyama, T.; Hasan, A.; Hasegawa, Y.; Hast, C.; Hastings, N. C.; Hasuko, K.; Hauke, A.; Hawkes, C. M.; Hayashi, K.; Hazumi, M.; Hee, C.; Heenan, E. M.; Heffernan, D.; Held, T.; Henderson, R.; Henderson, S. W.; Hertzbach, S. S.; Hervé, S.; Heß, M.; Heusch, C. A.; Hicheur, A.; Higashi, Y.; Higasino, Y.; Higuchi, I.; Hikita, S.; Hill, E. J.; Himel, T.; Hinz, L.; Hirai, T.; Hirano, H.; Hirschauer, J. F.; Hitlin, D. G.; Hitomi, N.; Hodgkinson, M. C.; Höcker, A.; Hoi, C. T.; Hojo, T.; Hokuue, T.; Hollar, J. J.; Hong, T. M.; Honscheid, K.; Hooberman, B.; Hopkins, D. A.; Horii, Y.; Hoshi, Y.; Hoshina, K.; Hou, S.; Hou, W. S.; Hryn'ova, T.; Hsiung, Y. B.; Hsu, C. L.; Hsu, S. C.; Hu, H.; Hu, T.; Huang, H. C.; Huang, T. J.; Huang, Y. C.; Huard, Z.; Huffer, M. E.; Hufnagel, D.; Hung, T.; Hutchcroft, D. E.; Hyun, H. J.; Ichizawa, S.; Igaki, T.; Igarashi, A.; Igarashi, S.; Igarashi, Y.; Igonkina, O.; Ikado, K.; Ikeda, H.; Ikeda, H.; Ikeda, K.; Ilic, J.; Inami, K.; Innes, W. R.; Inoue, Y.; Ishikawa, A.; Ishino, H.; Itagaki, K.; Itami, S.; Itoh, K.; Ivanchenko, V. N.; Iverson, R.; Iwabuchi, M.; Iwai, G.; Iwai, M.; Iwaida, S.; Iwamoto, M.; Iwasaki, H.; Iwasaki, M.; Iwashita, T.; Izen, J. M.; Jackson, D. J.; Jackson, F.; Jackson, G.; Jackson, P. S.; Jacobsen, R. G.; Jacoby, C.; Jaegle, I.; Jain, V.; Jalocha, P.; Jang, H. K.; Jasper, H.; Jawahery, A.; Jayatilleke, S.; Jen, C. M.; Jensen, F.; Jessop, C. P.; Ji, X. B.; John, M. J. J.; Johnson, D. R.; Johnson, J. R.; Jolly, S.; Jones, M.; Joo, K. K.; Joshi, N.; Joshi, N. J.; Judd, D.; Julius, T.; Kadel, R. W.; Kadyk, J. A.; Kagan, H.; Kagan, R.; Kah, D. H.; Kaiser, S.; Kaji, H.; Kajiwara, S.; Kakuno, H.; Kameshima, T.; Kaminski, J.; Kamitani, T.; Kaneko, J.; Kang, J. H.; Kang, J. S.; Kani, T.; Kapusta, P.; Karbach, T. M.; Karolak, M.; Karyotakis, Y.; Kasami, K.; Katano, G.; Kataoka, S. U.; Katayama, N.; Kato, E.; Kato, Y.; Kawai, H.; Kawai, M.; Kawamura, N.; Kawasaki, T.; Kay, J.; Kay, M.; Kelly, M. P.; Kelsey, M. H.; Kent, N.; Kerth, L. T.; Khan, A.; Khan, H. R.; Kharakh, D.; Kibayashi, A.; Kichimi, H.; Kiesling, C.; Kikuchi, M.; Kikutani, E.; Kim, B. H.; Kim, C. H.; Kim, D. W.; Kim, H.; Kim, H. J.; Kim, H. O.; Kim, H. W.; Kim, J. B.; Kim, J. H.; Kim, K. T.; Kim, M. J.; Kim, P.; Kim, S. K.; Kim, S. M.; Kim, T. H.; Kim, Y. I.; Kim, Y. J.; King, G. J.; Kinoshita, K.; Kirk, A.; Kirkby, D.; Kitayama, I.; Klemetti, M.; Klose, V.; Klucar, J.; Knecht, N. S.; Knoepfel, K. J.; Knowles, D. J.; Ko, B. R.; Kobayashi, N.; Kobayashi, S.; Kobayashi, T.; Kobel, M. J.; Koblitz, S.; Koch, H.; Kocian, M. L.; Kodyš, P.; Koeneke, K.; Kofler, R.; Koike, S.; Koishi, S.; Koiso, H.; Kolb, J. A.; Kolya, S. D.; Kondo, Y.; Konishi, H.; Koppenburg, P.; Koptchev, V. B.; Kordich, T. M. B.; Korol, A. A.; Korotushenko, K.; Korpar, S.; Kouzes, R. T.; Kovalskyi, D.; Kowalewski, R.; Kozakai, Y.; Kozanecki, W.; Kral, J. F.; Krasnykh, A.; Krause, R.; Kravchenko, E. A.; Krebs, J.; Kreisel, A.; Kreps, M.; Krishnamurthy, M.; Kroeger, R.; Kroeger, W.; Krokovny, P.; Kronenbitter, B.; Kroseberg, J.; Kubo, T.; Kuhr, T.; Kukartsev, G.; Kulasiri, R.; Kulikov, A.; Kumar, R.; Kumar, S.; Kumita, T.; Kuniya, T.; Kunze, M.; Kuo, C. C.; Kuo, T.-L.; Kurashiro, H.; Kurihara, E.; Kurita, N.; Kuroki, Y.; Kurup, A.; Kutter, P. E.; Kuznetsova, N.; Kvasnička, P.; Kyberd, P.; Kyeong, S. H.; Lacker, H. M.; Lae, C. K.; Lamanna, E.; Lamsa, J.; Lanceri, L.; Landi, L.; Lang, M. I.; Lange, D. J.; Lange, J. S.; Langenegger, U.; Langer, M.; Lankford, A. J.; Lanni, F.; Laplace, S.; Latour, E.; Lau, Y. P.; Lavin, D. R.; Layter, J.; Lebbolo, H.; LeClerc, C.; Leddig, T.; Leder, G.; Le Diberder, F.; Lee, C. L.; Lee, J.; Lee, J. S.; Lee, M. C.; Lee, M. H.; Lee, M. J.; Lee, S.-J.; Lee, S. E.; Lee, S. H.; Lee, Y. J.; Lees, J. P.; Legendre, M.; Leitgab, M.; Leitner, R.; Leonardi, E.; Leonidopoulos, C.; Lepeltier, V.; Leruste, Ph.; Lesiak, T.; Levi, M. E.; Levy, S. L.; Lewandowski, B.; Lewczuk, M. J.; Lewis, P.; Li, H.; Li, H. B.; Li, S.; Li, X.; Li, Y.; Gioi, L. Li; Libby, J.; Lidbury, J.; Lillard, V.; Lim, C. L.; Limosani, A.; Lin, C. S.; Lin, J. Y.; Lin, S. W.; Lin, Y. S.; Lindquist, B.; Lindsay, C.; Lista, L.; Liu, C.; Liu, F.; Liu, H.; Liu, H. M.; Liu, J.; Liu, R.; Liu, T.; Liu, Y.; Liu, Z. Q.; Liventsev, D.; Lo Vetere, M.; Locke, C. B.; Lockman, W. S.; Di Lodovico, F.; Lombardo, V.; London, G. W.; Lopes Pegna, D.; Lopez, L.; Lopez-March, N.; Lory, J.; LoSecco, J. M.; Lou, X. C.; Louvot, R.; Lu, A.; Lu, C.; Lu, M.; Lu, R. S.; Lueck, T.; Luitz, S.; Lukin, P.; Lund, P.; Luppi, E.; Lutz, A. M.; Lutz, O.; Lynch, G.; Lynch, H. L.; Lyon, A. J.; Lyubinsky, V. R.; MacFarlane, D. B.; Mackay, C.; MacNaughton, J.; Macri, M. M.; Madani, S.; Mader, W. F.; Majewski, S. A.; Majumder, G.; Makida, Y.; Malaescu, B.; Malaguti, R.; Malclés, J.; Mallik, U.; Maly, E.; Mamada, H.; Manabe, A.; Mancinelli, G.; Mandelkern, M.; Mandl, F.; Manfredi, P. F.; Mangeol, D. J. J.; Manoni, E.; Mao, Z. P.; Margoni, M.; Marker, C. E.; Markey, G.; Marks, J.; Marlow, D.; Marques, V.; Marsiske, H.; Martellotti, S.; Martin, E. C.; Martin, J. P.; Martin, L.; Martinez, A. J.; Marzolla, M.; Mass, A.; Masuzawa, M.; Mathieu, A.; Matricon, P.; Matsubara, T.; Matsuda, T.; Matsuda, T.; Matsumoto, H.; Matsumoto, S.; Matsumoto, T.; Matsuo, H.; Mattison, T. S.; Matvienko, D.; Matyja, A.; Mayer, B.; Mazur, M. A.; Mazzoni, M. A.; McCulloch, M.; McDonald, J.; McFall, J. D.; McGrath, P.; McKemey, A. K.; McKenna, J. A.; Mclachlin, S. E.; McMahon, S.; McMahon, T. R.; McOnie, S.; Medvedeva, T.; Melen, R.; Mellado, B.; Menges, W.; Menke, S.; Merchant, A. M.; Merkel, J.; Messner, R.; Metcalfe, S.; Metzler, S.; Meyer, N. T.; Meyer, T. I.; Meyer, W. T.; Michael, A. K.; Michelon, G.; Michizono, S.; Micout, P.; Miftakov, V.; Mihalyi, A.; Mikami, Y.; Milanes, D. A.; Milek, M.; Mimashi, T.; Minamora, J. S.; Mindas, C.; Minutoli, S.; Mir, L. M.; Mishra, K.; Mitaroff, W.; Miyake, H.; Miyashita, T. S.; Miyata, H.; Miyazaki, Y.; Moffitt, L. C.; Mohanty, G. B.; Mohapatra, A.; Mohapatra, A. K.; Mohapatra, D.; Moll, A.; Moloney, G. R.; Mols, J. P.; Mommsen, R. K.; Monge, M. R.; Monorchio, D.; Moore, T. B.; Moorhead, G. F.; Mora de Freitas, P.; Morandin, M.; Morgan, N.; Morgan, S. E.; Morganti, M.; Morganti, S.; Mori, S.; Mori, T.; Morii, M.; Morris, J. P.; Morsani, F.; Morton, G. W.; Moss, L. J.; Mouly, J. P.; Mount, R.; Mueller, J.; Müller-Pfefferkorn, R.; Mugge, M.; Muheim, F.; Muir, A.; Mullin, E.; Munerato, M.; Murakami, A.; Murakami, T.; Muramatsu, N.; Musico, P.; Nagai, I.; Nagamine, T.; Nagasaka, Y.; Nagashima, Y.; Nagayama, S.; Nagel, M.; Naisbit, M. T.; Nakadaira, T.; Nakahama, Y.; Nakajima, M.; Nakajima, T.; Nakamura, I.; Nakamura, T.; Nakamura, T. T.; Nakano, E.; Nakayama, H.; Nam, J. W.; Narita, S.; Narsky, I.; Nash, J. A.; Natkaniec, Z.; Nauenberg, U.; Nayak, M.; Neal, H.; Nedelkovska, E.; Negrini, M.; Neichi, K.; Nelson, D.; Nelson, S.; Neri, N.; Nesom, G.; Neubauer, S.; Newman-Coburn, D.; Ng, C.; Nguyen, X.; Nicholson, H.; Niebuhr, C.; Nief, J. Y.; Niiyama, M.; Nikolich, M. B.; Nisar, N. K.; Nishimura, K.; Nishio, Y.; Nitoh, O.; Nogowski, R.; Noguchi, S.; Nomura, T.; Nordby, M.; Nosochkov, Y.; Novokhatski, A.; Nozaki, S.; Nozaki, T.; Nugent, I. M.; O'Grady, C. P.; O'Neale, S. W.; O'Neill, F. G.; Oberhof, B.; Oddone, P. J.; Ofte, I.; Ogawa, A.; Ogawa, K.; Ogawa, S.; Ogawa, Y.; Ohkubo, R.; Ohmi, K.; Ohnishi, Y.; Ohno, F.; Ohshima, T.; Ohshima, Y.; Ohuchi, N.; Oide, K.; Oishi, N.; Okabe, T.; Okazaki, N.; Okazaki, T.; Okuno, S.; Olaiya, E. O.; Olivas, A.; Olley, P.; Olsen, J.; Ono, S.; Onorato, G.; Onuchin, A. P.; Onuki, Y.; Ooba, T.; Orimoto, T. J.; Oshima, T.; Osipenkov, I. L.; Ostrowicz, W.; Oswald, C.; Otto, S.; Oyang, J.; Oyanguren, A.; Ozaki, H.; Ozcan, V. E.; Paar, H. P.; Padoan, C.; Paick, K.; Palka, H.; Pan, B.; Pan, Y.; Panduro Vazquez, W.; Panetta, J.; Panova, A. I.; Panvini, R. S.; Panzenböck, E.; Paoloni, E.; Paolucci, P.; Pappagallo, M.; Paramesvaran, S.; Park, C. S.; Park, C. W.; Park, H.; Park, H. K.; Park, K. S.; Park, W.; Parry, R. J.; Parslow, N.; Passaggio, S.; Pastore, F. C.; Patel, P. M.; Patrignani, C.; Patteri, P.; Pavel, T.; Pavlovich, J.; Payne, D. J.; Peak, L. S.; Peimer, D. R.; Pelizaeus, M.; Pellegrini, R.; Pelliccioni, M.; Peng, C. C.; Peng, J. C.; Peng, K. C.; Peng, T.; Penichot, Y.; Pennazzi, S.; Pennington, M. R.; Penny, R. C.; Penzkofer, A.; Perazzo, A.; Perez, A.; Perl, M.; Pernicka, M.; Perroud, J.-P.; Peruzzi, I. M.; Pestotnik, R.; Peters, K.; Peters, M.; Petersen, B. A.; Petersen, T. C.; Petigura, E.; Petrak, S.; Petrella, A.; Petrič, M.; Petzold, A.; Pia, M. G.; Piatenko, T.; Piccolo, D.; Piccolo, M.; Piemontese, L.; Piemontese, M.; Pierini, M.; Pierson, S.; Pioppi, M.; Piredda, G.; Pivk, M.; Plaszczynski, S.; Polci, F.; Pompili, A.; Poropat, P.; Posocco, M.; Potter, C. T.; Potter, R. J. L.; Prasad, V.; Prebys, E.; Prencipe, E.; Prendki, J.; Prepost, R.; Prest, M.; Prim, M.; Pripstein, M.; Prudent, X.; Pruvot, S.; Puccio, E. M. T.; Purohit, M. V.; Qi, N. D.; Quinn, H.; Raaf, J.; Rabberman, R.; Raffaelli, F.; Ragghianti, G.; Rahatlou, S.; Rahimi, A. M.; Rahmat, R.; Rakitin, A. Y.; Randle-Conde, A.; Rankin, P.; Rashevskaya, I.; Ratkovsky, S.; Raven, G.; Re, V.; Reep, M.; Regensburger, J. J.; Reidy, J.; Reif, R.; Reisert, B.; Renard, C.; Renga, F.; Ricciardi, S.; Richman, J. D.; Ritchie, J. L.; Ritter, M.; Rivetta, C.; Rizzo, G.; Roat, C.; Robbe, P.; Roberts, D. A.; Robertson, A. I.; Robutti, E.; Rodier, S.; Rodriguez, D. M.; Rodriguez, J. L.; Rodriguez, R.; Roe, N. A.; Röhrken, M.; Roethel, W.; Rolquin, J.; Romanov, L.; Romosan, A.; Ronan, M. T.; Rong, G.; Ronga, F. J.; Roos, L.; Root, N.; Rosen, M.; Rosenberg, E. I.; Rossi, A.; Rostomyan, A.; Rotondo, M.; Roussot, E.; Roy, J.; Rozanska, M.; Rozen, Y.; Rozen, Y.; Rubin, A. E.; Ruddick, W. O.; Ruland, A. M.; Rybicki, K.; Ryd, A.; Ryu, S.; Ryuko, J.; Sabik, S.; Sacco, R.; Saeed, M. A.; Safai Tehrani, F.; Sagawa, H.; Sahoo, H.; Sahu, S.; Saigo, M.; Saito, T.; Saitoh, S.; Sakai, K.; Sakamoto, H.; Sakaue, H.; Saleem, M.; Salnikov, A. A.; Salvati, E.; Salvatore, F.; Samuel, A.; Sanders, D. A.; Sanders, P.; Sandilya, S.; Sandrelli, F.; Sands, W.; Sands, W. R.; Sanpei, M.; Santel, D.; Santelj, L.; Santoro, V.; Santroni, A.; Sanuki, T.; Sarangi, T. R.; Saremi, S.; Sarti, A.; Sasaki, T.; Sasao, N.; Satapathy, M.; Sato, Nobuhiko; Sato, Noriaki; Sato, Y.; Satoyama, N.; Satpathy, A.; Savinov, V.; Savvas, N.; Saxton, O. H.; Sayeed, K.; Schaffner, S. F.; Schalk, T.; Schenk, S.; Schieck, J. R.; Schietinger, T.; Schilling, C. J.; Schindler, R. H.; Schmid, S.; Schmitz, R. E.; Schmuecker, H.; Schneider, O.; Schnell, G.; Schönmeier, P.; Schofield, K. C.; Schott, G.; Schröder, H.; Schram, M.; Schubert, J.; Schümann, J.; Schultz, J.; Schumm, B. A.; Schune, M. H.; Schwanke, U.; Schwarz, H.; Schwiening, J.; Schwierz, R.; Schwitters, R. F.; Sciacca, C.; Sciolla, G.; Scott, I. J.; Seeman, J.; Seiden, A.; Seitz, R.; Seki, T.; Sekiya, A. I.; Semenov, S.; Semmler, D.; Sen, S.; Senyo, K.; Seon, O.; Serbo, V. V.; Serednyakov, S. I.; Serfass, B.; Serra, M.; Serrano, J.; Settai, Y.; Seuster, R.; Sevior, M. E.; Shakhova, K. V.; Shang, L.; Shapkin, M.; Sharma, V.; Shebalin, V.; Shelkov, V. G.; Shen, B. C.; Shen, D. Z.; Shen, Y. T.; Sherwood, D. J.; Shibata, T.; Shibata, T. A.; Shibuya, H.; Shidara, T.; Shimada, K.; Shimoyama, M.; Shinomiya, S.; Shiu, J. G.; Shorthouse, H. W.; Shpilinskaya, L. I.; Sibidanov, A.; Sicard, E.; Sidorov, A.; Sidorov, V.; Siegle, V.; Sigamani, M.; Simani, M. C.; Simard, M.; Simi, G.; Simon, F.; Simonetto, F.; Sinev, N. B.; Singh, H.; Singh, J. B.; Sinha, R.; Sitt, S.; Skovpen, Yu. I.; Sloane, R. J.; Smerkol, P.; Smith, A. J. S.; Smith, D.; Smith, D. S.; Smith, J. G.; Smol, A.; Snoek, H. L.; Snyder, A.; So, R. Y.; Sobie, R. J.; Soderstrom, E.; Soha, A.; Sohn, Y. S.; Sokoloff, M. D.; Sokolov, A.; Solagna, P.; Solovieva, E.; Soni, N.; Sonnek, P.; Sordini, V.; Spaan, B.; Spanier, S. M.; Spencer, E.; Speziali, V.; Spitznagel, M.; Spradlin, P.; Staengle, H.; Stamen, R.; Stanek, M.; Stanič, S.; Stark, J.; Steder, M.; Steininger, H.; Steinke, M.; Stelzer, J.; Stevanato, E.; Stocchi, A.; Stock, R.; Stoeck, H.; Stoker, D. P.; Stroili, R.; Strom, D.; Strother, P.; Strube, J.; Stugu, B.; Stypula, J.; Su, D.; Suda, R.; Sugahara, R.; Sugi, A.; Sugimura, T.; Sugiyama, A.; Suitoh, S.; Sullivan, M. K.; Sumihama, M.; Sumiyoshi, T.; Summers, D. J.; Sun, L.; Sun, S.; Sundermann, J. E.; Sung, H. F.; Susaki, Y.; Sutcliffe, P.; Suzuki, A.; Suzuki, J.; Suzuki, J. I.; Suzuki, K.; Suzuki, S.; Suzuki, S. Y.; Swain, J. E.; Swain, S. K.; T'Jampens, S.; Tabata, M.; Tackmann, K.; Tajima, H.; Tajima, O.; Takahashi, K.; Takahashi, S.; Takahashi, T.; Takasaki, F.; Takayama, T.; Takita, M.; Tamai, K.; Tamponi, U.; Tamura, N.; Tan, N.; Tan, P.; Tanabe, K.; Tanabe, T.; Tanaka, H. A.; Tanaka, J.; Tanaka, M.; Tanaka, S.; Tanaka, Y.; Tanida, K.; Taniguchi, N.; Taras, P.; Tasneem, N.; Tatishvili, G.; Tatomi, T.; Tawada, M.; Taylor, F.; Taylor, G. N.; Taylor, G. P.; Telnov, V. I.; Teodorescu, L.; Ter-Antonyan, R.; Teramoto, Y.; Teytelman, D.; Thérin, G.; Thiebaux, Ch.; Thiessen, D.; Thomas, E. W.; Thompson, J. M.; Thorne, F.; Tian, X. C.; Tibbetts, M.; Tikhomirov, I.; Tinslay, J. S.; Tiozzo, G.; Tisserand, V.; Tocut, V.; Toki, W. H.; Tomassini, E. W.; Tomoto, M.; Tomura, T.; Torassa, E.; Torrence, E.; Tosi, S.; Touramanis, C.; Toussaint, J. C.; Tovey, S. N.; Trapani, P. P.; Treadwell, E.; Triggiani, G.; Trincaz-Duvoid, S.; Trischuk, W.; Troost, D.; Trunov, A.; Tsai, K. L.; Tsai, Y. T.; Tsujita, Y.; Tsukada, K.; Tsukamoto, T.; Tuggle, J. M.; Tumanov, A.; Tung, Y. W.; Turnbull, L.; Turner, J.; Turri, M.; Uchida, K.; Uchida, M.; Uchida, Y.; Ueki, M.; Ueno, K.; Ujiie, N.; Ulmer, K. A.; Unno, Y.; Urquijo, P.; Ushiroda, Y.; Usov, Y.; Usseglio, M.; Usuki, Y.; Uwer, U.; Va'vra, J.; Vahsen, S. E.; Vaitsas, G.; Valassi, A.; Vallazza, E.; Vallereau, A.; Vanhoefer, P.; van Hoek, W. C.; Van Hulse, C.; van Winkle, D.; Varner, G.; Varnes, E. W.; Varvell, K. E.; Vasileiadis, G.; Velikzhanin, Y. S.; Verderi, M.; Versillé, S.; Vervink, K.; Viaud, B.; Vidal, P. B.; Villa, S.; Villanueva-Perez, P.; Vinograd, E. L.; Vitale, L.; Vitug, G. M.; Voß, C.; Voci, C.; Voena, C.; Volk, A.; von Wimmersperg-Toeller, J. H.; Vorobyev, V.; Vossen, A.; Vuagnin, G.; Vuosalo, C. O.; Wacker, K.; Wagner, A. P.; Wagner, D. L.; Wagner, G.; Wagner, M. N.; Wagner, S. R.; Wagoner, D. E.; Walker, D.; Walkowiak, W.; Wallom, D.; Wang, C. C.; Wang, C. H.; Wang, J.; Wang, J. G.; Wang, K.; Wang, L.; Wang, L. L.; Wang, P.; Wang, T. J.; Wang, W. F.; Wang, X. L.; Wang, Y. F.; Wappler, F. R.; Watanabe, M.; Watson, A. T.; Watson, J. E.; Watson, N. K.; Watt, M.; Weatherall, J. H.; Weaver, M.; Weber, T.; Wedd, R.; Wei, J. T.; Weidemann, A. W.; Weinstein, A. J. R.; Wenzel, W. A.; West, C. A.; West, C. G.; West, T. J.; White, E.; White, R. M.; Wicht, J.; Widhalm, L.; Wiechczynski, J.; Wienands, U.; Wilden, L.; Wilder, M.; Williams, D. C.; Williams, G.; Williams, J. C.; Williams, K. M.; Williams, M. I.; Willocq, S. Y.; Wilson, J. R.; Wilson, M. G.; Wilson, R. J.; Winklmeier, F.; Winstrom, L. O.; Winter, M. A.; Wisniewski, W. J.; Wittgen, M.; Wittlin, J.; Wittmer, W.; Wixted, R.; Woch, A.; Wogsland, B. J.; Won, E.; Wong, Q. K.; Wray, B. C.; Wren, A. C.; Wright, D. M.; Wu, C. H.; Wu, J.; Wu, S. L.; Wulsin, H. W.; Xella, S. M.; Xie, Q. L.; Xie, Y.; Xu, Z. Z.; Yéche, Ch.; Yamada, Y.; Yamaga, M.; Yamaguchi, A.; Yamaguchi, H.; Yamaki, T.; Yamamoto, H.; Yamamoto, N.; Yamamoto, R. K.; Yamamoto, S.; Yamanaka, T.; Yamaoka, H.; Yamaoka, J.; Yamaoka, Y.; Yamashita, Y.; Yamauchi, M.; Yan, D. S.; Yan, Y.; Yanai, H.; Yanaka, S.; Yang, H.; Yang, R.; Yang, S.; Yarritu, A. K.; Yashchenko, S.; Yashima, J.; Yasin, Z.; Yasu, Y.; Ye, S. W.; Yeh, P.; Yi, J. I.; Yi, K.; Yi, M.; Yin, Z. W.; Ying, J.; Yocky, G.; Yokoyama, K.; Yokoyama, M.; Yokoyama, T.; Yoshida, K.; Yoshida, M.; Yoshimura, Y.; Young, C. C.; Yu, C. X.; Yu, Z.; Yuan, C. Z.; Yuan, Y.; Yumiceva, F. X.; Yusa, Y.; Yushkov, A. N.; Yuta, H.; Zacek, V.; Zain, S. B.; Zallo, A.; Zambito, S.; Zander, D.; Zang, S. L.; Zanin, D.; Zaslavsky, B. G.; Zeng, Q. L.; Zghiche, A.; Zhang, B.; Zhang, J.; Zhang, J.; Zhang, L.; Zhang, L. M.; Zhang, S. Q.; Zhang, Z. P.; Zhao, H. W.; Zhao, M.; Zhao, Z. G.; Zheng, Y.; Zheng, Y. H.; Zheng, Z. P.; Zhilich, V.; Zhou, P.; Zhu, R. Y.; Zhu, Y. S.; Zhu, Z. M.; Zhulanov, V.; Ziegler, T.; Ziegler, V.; Zioulas, G.; Zisman, M.; Zito, M.; Zürcher, D.; Zwahlen, N.; Zyukova, O.; Živko, T.; Žontar, D.

    2014-11-01

    This work is on the Physics of the B Factories. Part A of this book contains a brief description of the SLAC and KEK B Factories as well as their detectors, BaBar and Belle, and data taking related issues. Part B discusses tools and methods used by the experiments in order to obtain results. The results themselves can be found in Part C. Please note that version 3 on the archive is the auxiliary version of the Physics of the B Factories book. This uses the notation alpha, beta, gamma for the angles of the Unitarity Triangle. The nominal version uses the notation phi_1, phi_2 and phi_3. Please cite this work as Eur. Phys. J. C74 (2014) 3026.

  20. Improvements to laser wakefield accelerated electron beam stability, divergence, and energy spread using three-dimensional printed two-stage gas cell targets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vargas, M.; Schumaker, W.; He, Z.-H.

    2014-04-28

    High intensity, short pulse lasers can be used to accelerate electrons to ultra-relativistic energies via laser wakefield acceleration (LWFA) [T. Tajima and J. M. Dawson, Phys. Rev. Lett. 43, 267 (1979)]. Recently, it was shown that separating the injection and acceleration processes into two distinct stages could prove beneficial in obtaining stable, high energy electron beams [Gonsalves et al., Nat. Phys. 7, 862 (2011); Liu et al., Phys. Rev. Lett. 107, 035001 (2011); Pollock et al., Phys. Rev. Lett. 107, 045001 (2011)]. Here, we use a stereolithography based 3D printer to produce two-stage gas targets for LWFA experiments on themore » HERCULES laser system at the University of Michigan. We demonstrate substantial improvements to the divergence, pointing stability, and energy spread of a laser wakefield accelerated electron beam compared with a single-stage gas cell or gas jet target.« less

  1. Sensitivity of Double-Shell Ignition Capsules to Asymmetric Drive

    NASA Astrophysics Data System (ADS)

    Tregillis, I. L.; Magelssen, G. R.; Delamater, N. D.; Gunderson, M. A.; Hoffman, N. M.

    2007-11-01

    Double-shell (DS) targets [1] present an alternative approach to ignition via the cryogenic single-shell point design [2]. Although these targets present unique fabrication challenges, they embody many attractive features, including non-cryogenic fielding and low threshold temperatures (˜4 keV) for volume ignition [3-4]. We have used 2D radiation-hydrodynamic modeling to survey the behavior of DS targets under asymmetric temperature drive in rugby vacuum hohlraums. The yield is robust against deviations from symmetric illumination, varying smoothly as a function of the imposed P2 and P4 amplitudes. Ignition occurs even when 10% or more of the drive is contained in Legendre P2 or P4 components, with yield reductions on the order of 50% for the most extreme cases investigated here. [1] P. Amendt et al., Phys. of Plasmas 9, 2221 (2002) [2] D. A. Callahan et al., Phys. of Plasmas 13, 56307 (2005) [3] P. Amendt et al., Phys. Rev. Lett. 94, 65004 (2005) [4] W. S. Varnum et al., Phys. Rev. Lett. 84, 5153 (2000)

  2. Response to “Comment on ‘Stationary self-focusing of Gaussian laser beam in relativistic thermal quantum plasma’” [Phys. Plasmas 21, 064701 (2014)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patil, S. D., E-mail: sdpatil-phy@rediffmail.com; Takale, M. V.

    2014-06-15

    Habibi and Ghamari have presented a Comment on our paper [Phys. Plasmas 20, 072703 (2013)] by examining quantum dielectric response in thermal quantum plasma. They have modeled the relativistic self-focusing of Gaussian laser beam in cold and warm quantum plasmas and reported that self-focusing length does not change in both situations. In this response, we have reached the following important conclusions about the comment itself.

  3. In-plane electrical transport in n-type selectively doped GaSb/AlGaSb multiquantum wells

    NASA Astrophysics Data System (ADS)

    Ghezzi, C.; Cioce, B.; Magnanini, R.; Parisini, A.

    2001-11-01

    Results are reported regarding in-plane electrical transport in n-type selectively doped GaSb/AlGaSb multiquantum wells. In the samples, which were grown by molecular beam epitaxy, only the central regions of the Al0.40Ga0.60Sb barriers were Te doped. Low-field, low-temperature Hall measurements in the dark demonstrated the presence in the GaSb wells of a degenerate electron gas with nonzero occupancy only for the lowest miniband. A positive persistent photoconductivity effect, related to the DX character of the Te impurity, was also observed. This behavior enabled the μ electron mobility to be measured at T=10 K as a function of the nS sheet carrier density. Since the experimental data were consistent with a dominant role of the interface roughness scattering in the limiting of μ, the height, Δ, and the lateral size, Λ, of the interface roughness were determined from the analysis of the μ=μ(nS) dependence. Acceptable values of Δ were obtained, consistent with results of structural investigations in single quantum well samples of GaSb/Al0.40Ga0.60Sb [E. Kh. Mukhamedzhanov, C. Bocchi, S. Franchi, A. Baraldi, R. Magnanini, and L. Nasi, J. Appl. Phys. 87, 4234 (2000)].

  4. Reply to “Comment on ‘Molybdenum sound velocity and shear modulus softening under shock compression’”

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nguyen, Jeffrey H.; Akin, Minta C.; Chau, Ricky

    2015-07-01

    Here, we respond to the Comment by Errandonea et al. [Phys. Rev. B 92, 026101 (2015)] on their reinterpretation of our published data [Nguyen et al., Phys. Rev. B 89, 174109 (2014)]. In the original paper, we argued that there is no solid-solid phase transition along the Hugoniot at 2.1 Mbars. There is, however, a softening of the shear modulus starting at 2.6 Mbars. Errandonea et al. [Phys. Rev. B 92, 026101 (2015)] reinterpreted our data and concluded that there is a structural change near 2.3 Mbars on the Hugoniot. Finally, we will explore the differences and agreements in themore » two interpretations of our data.« less

  5. Comment on "Critical wind speed at which trees break"

    NASA Astrophysics Data System (ADS)

    Albrecht, Axel; Badel, Eric; Bonnesoeur, Vivien; Brunet, Yves; Constant, Thiéry; Défossez, Pauline; de Langre, Emmanuel; Dupont, Sylvain; Fournier, Meriem; Gardiner, Barry; Mitchell, Stephen J.; Moore, John R.; Moulia, Bruno; Nicoll, Bruce C.; Niklas, Karl J.; Schelhaas, Mart-Jan; Spatz, Hans-Christof; Telewski, Frank W.

    2016-12-01

    Virot et al. [E. Virot et al., Phys. Rev. E 93, 023001 (2016), 10.1103/PhysRevE.93.023001] assert that the critical wind speed at which ⩾50% of all trees in a population break is ≈42 m/s, regardless of tree characteristics. We show that empirical data do not support this assertion, and that the assumptions underlying the theory used by Virot et al. are inconsistent with the biomechanics of trees.

  6. ERRATUM: High-resolution electron spectroscopy of the 1s23lnl' Be-like series in oxygen and neon. Test of theoretical data: I. Experimental method and theoretical background

    NASA Astrophysics Data System (ADS)

    Bordenave-Montesquieu, A.; Moretto-Capelle, P.; Bordenave-Montesquieu, D.

    2003-02-01

    The J. Phys. B publishing team would like to apologize to the authors of the above paper. In this paper, references [42] and [43] were printed incorrectly. The correct references are: [42] Bordenave-Montesquieu A, Gleizes A and Benoit-Cattin P 1982 Phys. Rev. A 25 245-67 [43] Bordenave-Montesquieu A et al 1987 J. Phys. B: At. Mol. Phys. 20 L695-703.

  7. Effect of particle size on phase transition among metastable alumina nanoparticles: A view from high resolution 2D solid-state 27Al NMR study

    NASA Astrophysics Data System (ADS)

    Kim, H.; Lee, S.

    2012-12-01

    The detailed knowledge of atomic structures of diverse metastable/stable polymorphs in alumina nanoparticles is essential to understand their macroscopic properties. Alumina undergoes successive phase transitions from metastable γ-, δ-, and θ-alumina to stable α-alumina depending on types of precursors, annealing duration, and temperature. As large surface area of nanoparticles plays an important role in controlling their phase transitions, it is also necessary to explore the effect of particle size on nature of phase transition. Solid-state ^{27}Al NMR allows us to determine the atomic structure of Al sites in diverse amorphous/disordered silicates including alumina. However, generally, the crystallographically distinct Al sites among alumina polymorphs were not fully resolved in ^{27}Al magic angle spinning (MAS) NMR spectrum without performing a simulation of overlapped peaks for Al sites of metastable alumina in the spectra. Unfortunately, the simulation of 27Al MAS NMR spectra for alumina nanoparticles cannot be achieved well due to unconfirmed NMR parameters for Al sites of γ- and δ-alumina. The recent progress in triple-quantum (3Q) MAS can provide the much higher resolution for crystallographically distinct Al sites in amorphous alumina (Lee et al., 2009, Phys. Rev. Lett., 103, 095501; Lee et al., 2010, J. Phys. Chem. C, 114, 13890-13894) and aluminosilicate glasses (Lee, 2011, Proc. Natl. Acad. Sci., 108, 6847-6852) as well as crystalline layer silicates (Lee and Weiss, 2008, Am. Mineral. 93, 1066-1071). In this study, we report the ^{27}Al 2D 3QMAS and 1D MAS NMR spectra for alumina nanoparticles with varying particle size (e.g., 15, 19, and 27 nm) and temperature with an aim to explore the atomic structure of alumina polymorphs and nature of their phase transition sequence. The ^{27}Al 2D 3QMAS spectra show the resolved crystallographically distinct ^{[6]}Al and ^{[4]}Al sites in (γ, δ)-, θ-, and α-alumina in nanoparticles consisting of random

  8. Comment on 'Direct observation of the {sup 2}D{sub 3/2}-{sup 2}D{sub 5/2} ground-state splitting in Xe{sup 9+}''

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Biedermann, C.; Radtke, R.

    2007-06-15

    We have found that xenon in different charge states, namely, Xe{sup 9+} and Xe{sup 31+}, can contribute to the radiation in the 598 nm spectral range. Our observation resolves the discrepancy of line identification given by Takacs et al. [Phys. Rev. A 73, 052505 (2006)] and Crespo et al. [Can. J. Phys. 80, 1687 (2002)].

  9. Induced magnetic structure in exchange-coupled ferro-/antiferromagnet thin films

    NASA Astrophysics Data System (ADS)

    Morales, Rafael

    2007-03-01

    The most prominent feature observed in exchange-coupled ferromagnetic/ antiferromagnetic (FM/AF) bilayers is the so-called exchange bias field (HEB), i.e. the shift of the hysteresis loop along the magnetic field axis. However the exchange bias phenomenon can induce other interesting effects on the FM. In this talk we show two methods to establish a bi-domain state in the FM, due to the coexistence of domains with opposite sign of HEB [1-3]. Magneto-optical, polarized neutron and soft X-ray measurements show that this lateral structure becomes more complex for low magnetocrystalline anisotropy materials where a spin depth profile is created in the FM due to the exchange coupling with the AF [4-6]. The internal magnetic structure in the AF and its role on exchange bias has also been investigated using FM/AF/FM trilayers. These studies demonstrate that the bulk spin configuration in the AF plays a crucial role in the pinning of uncompensated spins at the interface thus determining the HEB . Supported by the US-DOE, European Marie-Curie-OIF and the Alfred P. Sloan Foundation. [1] O. Petracic et al. Appl. Phys. Lett. 87, 222509 (2005) [2] I. V. Roshchin et al. Europhys. Lett. 71, 297 (2005) [3] J. Olamit et al. Phys. Rev. B 72, 012408 (2005) [4] R. Morales et al. Appl. Phys. Lett. 89, 072504 (2006) [5] S. Roy et al. Phys. Rev. Lett. 95, 047201 (2005) [6] Z-P. Li et al. Phys. Rev. Lett. 96, 217205 (2006)

  10. The new insight into dynamic crossover in glass forming liquids from the apparent enthalpy analysis

    NASA Astrophysics Data System (ADS)

    Martinez-Garcia, Julio Cesar; Martinez-Garcia, Jorge; Rzoska, Sylwester J.; Hulliger, Jürg

    2012-08-01

    One of the most intriguing phenomena in glass forming systems is the dynamic crossover (TB), occurring well above the glass temperature (Tg). So far, it was estimated mainly from the linearized derivative analysis of the primary relaxation time τ(T) or viscosity η(T) experimental data, originally proposed by Stickel et al. [J. Chem. Phys. 104, 2043 (1996), 10.1063/1.470961; Stickel et al. J. Chem. Phys. 107, 1086 (1997)], 10.1063/1.474456. However, this formal procedure is based on the general validity of the Vogel-Fulcher-Tammann equation, which has been strongly questioned recently [T. Hecksher et al. Nature Phys. 4, 737 (2008), 10.1038/nphys1033; P. Lunkenheimer et al. Phys. Rev. E 81, 051504 (2010), 10.1103/PhysRevE.81.051504; J. C. Martinez-Garcia et al. J. Chem. Phys. 134, 024512 (2011)], 10.1063/1.3514589. We present a qualitatively new way to identify the dynamic crossover based on the apparent enthalpy space (H_a^' = {{dln τ }/{d({1/T})}}) analysis via a new plot ln H_a^' vs. 1/T supported by the Savitzky-Golay filtering procedure for getting an insight into the noise-distorted high order derivatives. It is shown that depending on the ratio between the "virtual" fragility in the high temperature dynamic domain (mhigh) and the "real" fragility at Tg (the low temperature dynamic domain, m = mlow) glass formers can be splitted into two groups related to f < 1 and f > 1, (f = mhigh/mlow). The link of this phenomenon to the ratio between the apparent enthalpy and activation energy as well as the behavior of the configurational entropy is indicated.

  11. Quantum Criticality and Superconductivity in β-YbAlB4

    NASA Astrophysics Data System (ADS)

    Nakatsuji, Satoru

    2009-03-01

    Heavy fermion systems have provided a number of prototypical compounds to study unconventional superconductivity and non-Fermi-liquid (NFL) states. A long standing issue in the research of heavy fermion superconductivity in 4f intermetallics is the dramatically different behavior between the electron like Ce (4f^1) and hole like Yb (4f^13) compounds. While superconductivity has been found in a number of Ce based heavy fermion compounds, no superconductivity has been reported for the corresponding Yb systems. In this talk, I present our recent finding of the superconductivity in the new heavy fermion system β-YbAlB4 [1-3]. The superconducting transition temperature is 80 mK, and above it, the system exhibits pronounced NFL behavior in the transport and thermodynamic properties [2,3]. Furthermore, the magnetic field dependence of the NFL behavior indicates that the system is a rare example of a pure metal that displays quantum criticality at ambient pressure and under zero magnetic field. Using our latest results, we discuss the detailed properties of superconductivity and quantum criticality. This is the work performed in collaboration with K. Kuga, Y. Matsumoto, T. Tomita, Y. Machida, T. Tayama, T. Sakakibara, Y. Karaki, H. Ishimoto, S. Yonezawa, Y. Maeno, E. Pearson, G. G. Lonzarich, L.Balicas, H. Lee, and Z. Fisk. [4pt] [1] Robin T. Macaluso, Satoru Nakatsuji, Kentaro Kuga, Evan Lyle Thomas, Yo Machida, Yoshiteru Maeno, Zachary Fisk, and Julia Y. Chan, Chem. Mater. 19 1918 (2007). [0pt] [2] S. Nakatsuji, K.Kuga, Y. Machida, T. Tayama, T. Sakakibara, Y. Karaki, H. Ishimoto, S. Yonezawa, Y. Maeno, E. Pearson, G. G. Lonzarich, L.Balicas, H. Lee, and Z. Fisk, Nature Phys 4, 603-607 (2008). [0pt] [3] K. Kuga, Y. Karaki, Y. Matsumoto, Y. Machida, and S. Nakatsuji, Phys. Rev. Lett. 101, 137004 (2008).

  12. Unravelling the Conformational Landscape of Nicotinoids: the Structure of Cotinine by Broadband Rotational Spectroscopy

    NASA Astrophysics Data System (ADS)

    Uriarte, Iciar; Ecija, Patricia; Cocinero, Emilio J.; Perez, Cristobal; Caballero-Mancebo, Elena; Lesarri, Alberto

    2015-06-01

    Alkaloids such as nicotine, cotinine or anabasine share a common floppy structural motif consisting of a two-ring assembly with a 3-pyridil methylamine skeleton. In order to investigate the structure-activity relationship of these biomolecules, structural studies with rotational resolution have been carried out for nicotine and anabasine in the gas phase, where these molecules can be probed in an "interaction-free" environment (no solvent or crystal-packing interactions). We hereby present a structural investigation of cotinine in a jet expansion using the chirped-pulse Fourier-transform microwave (CP-FTMW) spectrometer recently built at the University of the Basque Country (UPV-EHU). The rotational spectrum (6-18 GHz) reveals the presence of two different conformations. The conformational preferences of cotinine originate from the internal rotation of the two ring moieties, the detected species differing in a near 180° rotation of pyridine. The final structure is modulated by steric effects. J.-U. Grabow, S. Mata, J. L. Alonso, I. Peña, S. Blanco, J. C. López, C. Cabezas, Phys. Chem. Chem. Phys. 2011, 13, 21063. A. Lesarri, E. J. Cocinero, L. Evangelisti, R. D. Suenram, W. Caminati, J.-U. Grabow, Chem. Eur. J. 2010, 16, 10214.

  13. Effect of interfacial slip on the thin film drainage time for two equal-sized, surfactant-free drops undergoing a head-on collision: A scaling analysis

    NASA Astrophysics Data System (ADS)

    Ramachandran, A.; Leal, L. G.

    2016-10-01

    Using a scaling analysis, we assess the impact of interfacial slip on the time required for the thin liquid film between two drops undergoing a head-on collision to drain to the critical thickness for rupture by van der Waals forces. Interfacial slip is included in our continuum development using a Navier slip boundary condition, with the slip coefficient modeled using previous theories [Helfand and Tagami, J. Chem. Phys. 57, 1812 (1972), 10.1063/1.1678491; Goveas and Fredrickson, Eur. Phys. J. B 2, 79 (1998), 10.1007/s100510050228]. Slip decreases hydrodynamic resistance and speeds up film drainage. It renders the dependence of the drainage time on capillary number stronger in the spherical-film regime, but, interestingly, this dependence is altered only weakly in the dimpled-film regime. A subtle effect of slip is that it increases the range of capillary numbers in which the film remains predominantly spherical in shape during drainage (as opposed to being dimpled), leading to significantly faster drainage for these capillary numbers. Slip also leads to an increase in the critical capillary number beyond which coalescence is not possible in a head-collision.

  14. The bimodal distribution spin Seebeck effect enhancement in epitaxial Ni0.65Zn0.35Al0.8Fe1.2O4 thin film

    NASA Astrophysics Data System (ADS)

    Wang, Hua; Hou, Dazhi; Kikkawa, Takashi; Ramos, Rafael; Shen, Ka; Qiu, Zhiyong; Chen, Yao; Umeda, Maki; Shiomi, Yuki; Jin, Xiaofeng; Saitoh, Eiji

    2018-04-01

    The temperature dependence of the spin Seebeck effect (SSE) in epitaxial Ni0.65Zn0.35Al0.8Fe1.2O4 (NZA ferrite) thin film has been investigated systematically. The SSE at high fields shows a bimodal distribution enhancement from 3 K to 300 K and is well fitted with a double-peak Lorentzian function. We speculate the symmetric SSE enhancement in Pt/NZA ferrite bilayer, which is different from the magnon polarons induced asymmetric spikes in the SSE of Pt/YIG [T. Kikkawa et al. Phys. Rev. Lett. 117, 207203 (2016)], may result from the magnon-phonon interactions occurring at the intersections of the quantized magnon and phonon dispersions. The SSE results are helpful for the investigation of the magnon-phonon interaction in the magnetic ultrathin films.

  15. Blood Volume: Importance and Adaptations to Exercise Training, Environmental Stresses and Trauma Sickness

    DTIC Science & Technology

    2000-02-01

    M. A. Selland, R. G. McCullough, et al. Beta-adrenergic blockade does not prevent polycythemia or decrease in plasma volume in men at 4300 m altitude...72:1887–1894, 1992. 65. GROVER, R. F., M. A. SELLAND, R. G. MCCULLOUGH, et al. Beta-adrenergic blockade does not prevent polycythemia or decrease in...tolerance following artificially induced polycythemia . Eur. J. Appl. Physiol. 71:416–423, 1995. 118. PEARCY, M., S. ROBINSON, D. I. MILLER, J. T. THOMAS

  16. Response to “Comment on ‘General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation’” [Phys. Fluids 26, 119101 (2014)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Van Gorder, Robert A., E-mail: rav@knights.ucf.edu

    2014-11-15

    In R. A. Van Gorder, “General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation,” Phys. Fluids 26, 065105 (2014) I discussed properties of generalized vortex filaments exhibiting purely rotational motion under the low-temperature Svistunov model of the local induction approximation. Such solutions are stationary in terms of translational motion. In the Comment [N. Hietala, “Comment on ‘General rotating quantum vortex filaments in the low-temperature Svistunov model of the local induction approximation’ [Phys. Fluids 26, 065105 (2014)],” Phys. Fluids 26, 119101 (2014)], the author criticizes my paper for not including translational motion (although it wasmore » clearly stated that the filament motion was assumed rotational). As it turns out, if one is interested in studying the geometric structure of solutions (which was the point of my paper), one obtains the needed qualitative results on the structure of such solutions by studying the purely rotational case. Nevertheless, in this Response I shall discuss the vortex filaments that have both rotational and translational motions. I then briefly discuss why one might want to study such generalized rotating filament solutions, in contrast to simple the standard helical or planar examples (which are really special cases). I also discuss how one can study the time evolution of filaments which exhibit more complicated dynamics than pure translation and rotation. Doing this, one can study non-stationary solutions which initially appear purely rotational and gradually display other dynamics as the filaments evolve.« less

  17. An exploration of advanced X-divertor scenarios on ITER

    NASA Astrophysics Data System (ADS)

    Covele, B.; Valanju, P.; Kotschenreuther, M.; Mahajan, S.

    2014-07-01

    It is found that the X-divertor (XD) configuration (Kotschenreuther et al 2004 Proc. 20th Int. Conf. on Fusion Energy (Vilamoura, Portugal, 2004) (Vienna: IAEA) CD-ROM file [IC/P6-43] www-naweb.iaea.org/napc/physics/fec/fec2004/datasets/index.html, Kotschenreuther et al 2006 Proc. 21st Int. Conf. on Fusion Energy 2006 (Chengdu, China, 2006) (Vienna: IAEA), CD-ROM file [IC/P7-12] www-naweb.iaea.org/napc/physics/FEC/FEC2006/html/index.htm, Kotschenreuther et al 2007 Phys. Plasmas 14 072502) can be made with the conventional poloidal field (PF) coil set on ITER (Tomabechi et al and Team 1991 Nucl. Fusion 31 1135), where all PF coils are outside the TF coils. Starting from the standard divertor, a sequence of desirable XD configurations are possible where the PF currents are below the present maximum design limits on ITER, and where the baseline divertor cassette is used. This opens the possibility that the XD could be tested and used to assist in high-power operation on ITER, but some further issues need examination. Note that the increased major radius of the super-X-divertor (Kotschenreuther et al 2007 Bull. Am. Phys. Soc. 53 11, Valanju et al 2009 Phys. Plasmas 16 5, Kotschenreuther et al 2010 Nucl. Fusion 50 035003, Valanju et al 2010 Fusion Eng. Des. 85 46) is not a feature of the XD geometry. In addition, we present an XD configuration for K-DEMO (Kim et al 2013 Fusion Eng. Des. 88 123) to demonstrate that it is also possible to attain the XD configuration in advanced tokamak reactors with all PF coils outside the TF coils. The results given here for the XD are far more encouraging than recent calculations by Lackner and Zohm (2012 Fusion Sci. Technol. 63 43) for the Snowflake (Ryutov 2007 Phys. Plasmas 14 064502, Ryutov et al 2008 Phys. Plasmas 15 092501), where the required high PF currents represent a major technological challenge. The magnetic field structure in the outboard divertor SOL (Kotschenreuther 2013 Phys. Plasmas 20 102507) in the recently created

  18. Mapping Nanoscale Absorption of Femtosecond Laser Pulses Using Plasma Explosion Imaging

    DTIC Science & Technology

    2014-08-06

    Libby, S. B.; et al. Observation and Control of Shock Waves in Indivi- dual Nanoplasmas . Phys. Rev. Lett. 2014, 112, 115004. 17. Zhang, X.; Smith, K. a...Laser Light. Phys. Plasmas 2005, 12, 056703. 24. Lezius, M.; Dobosz, S. Hot Nanoplasmas from Intense Laser Irradiation of Argon Clusters. J. Phys. B

  19. Toroidal Alfven Waves in Advanced Tokamaks

    NASA Astrophysics Data System (ADS)

    Berk, Herbert L.

    2003-10-01

    In burning plasma experiments, alpha particles have speeds that readily resonate with shear Alfven waves. It is essential to understand this Alfven wave spectrum for toroidal plasma confinement. Most interest has focused on the Toroidal Alfven Eigenmode (TAE), and a method of analysis has been developed to understand the structure of this mode at a flux surface with a given magnetic shear. However, this model fails when the shear is too low or reversed. In this case a new method of analysis is required, which must incorporate novel fluid-like effects from the energetic particles [1] and also include effects that are second order in the inverse toroidal aspect ratio. With this new method [2] we can obtain spectral features that agree with experimental results. In particular, this theory gives an explanation for the so-called Cascade modes that have been observed in JT-60 [3], JET [4], and TFTR [5]. For these Cascade modes, slow upward frequency sweeping is observed, beginning from frequencies below the TAE range but then often blending into the TAE range of frequencies. The theoretical understanding of the Cascades modes has evolved to the point where these modes can be used as a diagnostic "signature" [6] to experimentally optimize the formation of thermal barriers in reversed-shear operation when the minimum q value is an integer. [1] H. L. Berk et al., Phys. Rev. Lett. 87, 185 (2002). [2] B. N. Breizman et al., submitted to Phys. Plasmas (2003). [3] H. Kimura et al., Nucl. Fusion 38, 1303 (1998). [4] S. Sharapov et al., Phys. Lett. A 289, 127 (2001); S. Sharapov, Phys. Plasmas 9, 2027 (2002). [5] R. Nazikian, H. L. Berk, et al., Bull. Am. Phys. Soc. 47, 327 (2002). [6] E. Joffrin et al., Plasma Phys. Contr. Fusion 44, 1739 (2002); E. Joffrin et al., in Proc. 2002 IAEA Fusion Energy Conference, submitted to Nucl. Fusion.

  20. Soliton solutions of the quantum Zakharov-Kuznetsov equation which arises in quantum magneto-plasmas

    NASA Astrophysics Data System (ADS)

    Sindi, Cevat Teymuri; Manafian, Jalil

    2017-02-01

    In this paper, we extended the improved tan(φ/2)-expansion method (ITEM) and the generalized G'/G-expansion method (GGEM) proposed by Manafian and Fazli (Opt. Quantum Electron. 48, 413 (2016)) to construct new types of soliton wave solutions of nonlinear partial differential equations (NPDEs). Moreover, we use of the improvement of the Exp-function method (IEFM) proposed by Jahani and Manafian (Eur. Phys. J. Plus 131, 54 (2016)) for obtaining solutions of NPDEs. The merit of the presented three methods is they can find further solutions to the considered problems, including soliton, periodic, kink, kink-singular wave solutions. This paper studies the quantum Zakharov-Kuznetsov (QZK) equation by the aid of the improved tan(φ/2)-expansion method, the generalized G'/G-expansion method and the improvement of the Exp-function method. Moreover, the 1-soliton solution of the modified QZK equation with power law nonlinearity is obtained by the aid of traveling wave hypothesis with the necessary constraints in place for the existence of the soliton. Comparing our new results with Ebadi et al. results (Astrophys. Space Sci. 341, 507 (2012)), namely, G'/G-expansion method, exp-function method, modified F-expansion method, shows that our results give further solutions. Finally, these solutions might play an important role in engineering, physics and applied mathematics fields.

  1. Non-unique monopole oscillations of harmonically confined Yukawa systems

    NASA Astrophysics Data System (ADS)

    Ducatman, Samuel; Henning, Christian; Kaehlert, Hanno; Bonitz, Michael

    2008-11-01

    Recently it was shown that the Breathing Mode (BM), the mode of uniform radial expansion and contraction, which is well known from harmonically confined Coulomb systems [1], does not exist in general for other systems [2]. As a consequence the monopole oscillation (MO), the radial collective excitation, is not unique, but there are several MO with different frequencies. Within this work we show simulation results of those monopole oscillations of 2-dimensional harmonically confined Yukawa systems, which are known from, e.g., dusty plasma crystals [3,4]. We present the corresponding spectrum of the particle motion, including analysis of the frequencies found, and compare with theoretical investigations.[1] D.H.E. Dubin and J.P. Schiffer, Phys. Rev. E 53, 5249 (1996)[2] C. Henning at al., accepted for publication in Phys. Rev. Lett. (2008)[3] A. Melzer et al., Phys. Rev. Lett. 87, 115002 (2001)[4] M. Bonitz et al., Phys. Rev. Lett. 96, 075001 (2006)

  2. Recovering information of tunneling spectrum from weakly isolated horizon

    NASA Astrophysics Data System (ADS)

    Chen, Ge-Rui; Huang, Yong-Chang

    2015-02-01

    In this paper we investigate the properties of tunneling spectrum from weakly isolated horizon (WIH)—a locally defined black hole. We find that there exist correlations among Hawking radiations from a WIH, information can be carried out by such correlations, and the radiation is an entropy conservation process. Through revisiting the calculation of the tunneling spectrum from a WIH, we find that Zhang et al.'s (Ann Phys 326:350, 2011) requirement that radiated particles have the same angular momenta of a unit mass as that of the black hole is unnecessary, and the energy and angular momenta of the emitted particles are very arbitrary, restricted only by keeping the cosmic censorship hypothesis of black holes. So we resolve the information loss paradox based on the method of Zhang et al. (Phys Lett B 675:98, 2009; Ann Phys 326:350, 2011; Int J Mod Phys D 22:1341014, 2013) in a general case.

  3. An Ensemble of Atomic Fountains

    DTIC Science & Technology

    2012-05-01

    1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 ph as e (n s) 56000559005580055700 MJD 8 10-16 2 4 6 8 10-15 2 4 ov er la pp in g Al la n de vi at io n 104... Metrologia 49, 49-56 (2012). [3] N. Ashby et al., Phys. Rev. Lett. 98, 070802 (2007). [4] S. J. Ferrell, et al., Phys. Rev. A 76, 062104 (2007). [5] T. M

  4. Correction: Assembly and relaxation behaviours of phosphatidylethanolamine monolayers investigated by polarization and frequency resolved SFG-VS.

    PubMed

    Wei, Feng; Xiong, Wei; Li, Wenhui; Lu, Wangting; Allen, Heather C; Zheng, Wanquan

    2016-06-14

    Correction for 'Assembly and relaxation behaviours of phosphatidylethanolamine monolayers investigated by polarization and frequency resolved SFG-VS' by Feng Wei et al., Phys. Chem. Chem. Phys., 2015, 17, 25114-25122.

  5. Reply to "Comment on `Particle path through a nested Mach-Zehnder interferometer' "

    NASA Astrophysics Data System (ADS)

    Griffiths, Robert B.

    2018-02-01

    While much of the technical analysis in the preceding Comment is correct, in the end it confirms the conclusion reached in my previous work [Phys. Rev. A 94, 032115 (2016), 10.1103/PhysRevA.94.032115]: A consistent histories analysis provides no support for the claim of counterfactual quantum communication put forward by Salih et al. [Phys. Rev. Lett. 110, 170502 (2013), 10.1103/PhysRevLett.110.170502].

  6. Al 1s-2p Absorption Spectroscopy of Shock-Wave Heating and Compression in Laser-Driven Planar Foil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sawada, H.; Regan, S.P.; Radha, P.B.

    Time-resolved Al 1s-2p absorption spectroscopy is used to diagnose direct-drive, shock-wave heating and compression of planar targets having nearly Fermi-degenerate plasma conditions (Te ~ 10–40 eV, rho ~ 3–11 g/cm^3) on the OMEGA Laser System [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)]. A planar plastic foil with a buried Al tracer layer was irradiated with peak intensities of 10^14–10^15 W/cm^2 and probed with the pseudocontinuum M-band emission from a point-source Sm backlighter in the range of 1.4–1.7 keV. The laser ablation process launches 10–70 Mbar shock waves into the CH/Al/CH target. The Al 1s-2p absorption spectra weremore » analyzed using the atomic physic code PRISMSPECT to infer Te and rho in the Al layer, assuming uniform plasma conditions during shock-wave heating, and to determine when the heat front penetrated the Al layer. The drive foils were simulated with the one-dimensional hydrodynamics code LILAC using a flux-limited (f =0.06 and f =0.1) and nonlocal thermal-transport model [V. N. Goncharov et al., Phys. Plasmas 13, 012702 (2006)]. The predictions of simulated shock-wave heating and the timing of heat-front penetration are compared to the observations. The experimental results for a wide variety of laser-drive conditions and buried depths have shown that the LILAC predictions using f = 0.06 and the nonlocal model accurately model the shock-wave heating and timing of the heat-front penetration while the shock is transiting the target. The observed discrepancy between the measured and simulated shock-wave heating at late times of the drive can be explained by the reduced radiative heating due to lateral heat flow in the corona.« less

  7. Randomized Controlled Trial of the Focus Parent Training for Toddlers with Autism: 1-Year Outcome

    ERIC Educational Resources Information Center

    Oosterling, Iris; Visser, Janne; Swinkels, Sophie; Rommelse, Nanda; Donders, Rogier; Woudenberg, Tim; Roos, Sascha; van der Gaag, Rutger Jan; Buitelaar, Jan

    2010-01-01

    This randomized controlled trial compared results obtained after 12 months of nonintensive parent training plus care-as-usual and care-as-usual alone. The training focused on stimulating joint attention and language skills and was based on the intervention described by Drew et al. (Eur Child Adolesc Psychiatr 11:266-272, 2002). Seventy-five…

  8. Reliability-Limiting Defects in GaN/AlGaN High Electron Mobility Transistors

    DTIC Science & Technology

    2011-12-01

    GaN grown by plasma-assisted molecular beam epitaxy”, Appl. Phys. Lett., vol. 77, no. 18, pp. 2885- 2887, 2000. [24] A. Hierro , A. R. Arehart, B...defects and impurities: Applications to III-nitrides”, J. Appl. Phys., vol. 95, pp.3851-3879, 2004. [43] A. Hierro , S. A. Ringel, M. Hansen, J. S

  9. A comparison of three radiation models for the calculation of nozzle arcs

    NASA Astrophysics Data System (ADS)

    Dixon, C. M.; Yan, J. D.; Fang, M. T. C.

    2004-12-01

    Three radiation models, the semi-empirical model based on net emission coefficients (Zhang et al 1987 J. Phys. D: Appl. Phys. 20 386-79), the five-band P1 model (Eby et al 1998 J. Phys. D: Appl. Phys. 31 1578-88), and the method of partial characteristics (Aubrecht and Lowke 1994 J. Phys. D: Appl.Phys. 27 2066-73, Sevast'yanenko 1979 J. Eng. Phys. 36 138-48), are used to calculate the radiation transfer in an SF6 nozzle arc. The temperature distributions computed by the three models are compared with the measurements of Leseberg and Pietsch (1981 Proc. 4th Int. Symp. on Switching Arc Phenomena (Lodz, Poland) pp 236-40) and Leseberg (1982 PhD Thesis RWTH Aachen, Germany). It has been found that all three models give similar distributions of radiation loss per unit time and volume. For arcs burning in axially dominated flow, such as arcs in nozzle flow, the semi-empirical model and the P1 model give accurate predictions when compared with experimental results. The prediction by the method of partial characteristics is poorest. The computational cost is the lowest for the semi-empirical model.

  10. Fabrication and electrical characterization of Al/diazo compound containing polyoxy chain/p-Si device structure

    NASA Astrophysics Data System (ADS)

    Birel, Ozgul; Kavasoglu, Nese; Kavasoglu, A. Sertap; Dincalp, Haluk; Metin, Bengul

    2013-03-01

    Diazo-compounds are important class of chemical compounds in terms of optical and electronic properties which make them potentially attractive for device applications. Diazo compound containing polyoxy chain has been deposited on p-Si. Current-voltage characteristics of Al/diazo compound containing polyoxy chain/p-Si structure present rectifying behaviour. The Schottky barrier height (SBH), diode factor (n), reverse saturation current (Io), interface state density (Nss) of Al/diazo compound containing polyoxy chain/p-Si structure have been calculated from experimental forward bias current-voltage data measured in the temperature range 100-320 K and capacitance-voltage data measured at room temperature and 1 MHz. The calculated values of SBH have ranged from 0.041 and 0.151 eV for the high and low temperature regions. Diode factor values fluctuate between the values 14 and 18 with temperature. Such a high diode factors stem from disordered interface layer in a junction structure as stated by Brötzmann et al. [M. Brötzmann, U. Vetter, H. Hofsäss, J. Appl. Phys. 106 (2009) 063704]. The calculated values of saturation current have ranged from 3×10-11 A to 2.79×10-7 A and interface state density have ranged from 5×1011 eV-1 cm-2 and 4×1013 eV-1 cm-2 as temperature increases. Results show that Al/diazo compound containing polyoxy chain/p-Si structure is a valuable candidate for device applications in terms of low reverse saturation current and low interface state density.

  11. Correction: Influence of particle size and dielectric environment on the dispersion behaviour and surface plasmon in nickel nanoparticles.

    PubMed

    Sharma, Vikash; Chotia, Chanderbhan; Tarachand; Ganesan, Vedachalaiyer; Okram, Gunadhor S

    2017-07-21

    Correction for 'Influence of particle size and dielectric environment on the dispersion behaviour and surface plasmon in nickel nanoparticles' by Vikash Sharma et al., Phys. Chem. Chem. Phys., 2017, 19, 14096-14106.

  12. Multichannel-quantum-defect-theory treatment of preionized and predissociated triplet gerade levels of H2

    NASA Astrophysics Data System (ADS)

    Matzkin, A.; Jungen, Ch.; Ross, S. C.

    2000-12-01

    Multichannel quantum defect theory (MQDT) is used to calculate highly excited predissociated and preionized triplet gerade states of H2. The treatment is ab initio and is based on the clamped-nuclei quantum-defect matrices and dipole transition moments derived from quantum-chemical potential energy curves by Ross et al. [Can. J. Phys. (to be published)]. Level positions, predissociation or preionization widths and relative intensities are found to be in good agreement with those observed by Lembo et al. [Phys. Rev. A 38, 3447 (1988); J. Chem. Phys. 92, 2219 (1990)] by an optical-optical double resonance photoionization or depletion technique.

  13. 0.27 GW Soft X-Ray Pulse Using a Plasma-Based Amplification Chain

    NASA Astrophysics Data System (ADS)

    Oliva, E.; Fajardo, M.; Velarde, P.; Ros, D.; Sebban, S.; Zeitoun, P.

    Seeding plasma-based soft-x-ray lasers (PBSXRL) with high order harmonics (HOH) has been demonstrated in plasmas created from gas targets (Zeitoun et al. in Nature 431:426, 2004 and solid targets (Wang et al. in Nat. Photonics 2:94, 2008), obtaining 1 μJ, 1 ps pulses. Reaching multi-microJoule, hundreds of fs regime is the ultimate goal. Recent papers (Oliva et al. in Opt. Lett. 34(17):2640-2642, 2009; Phys. Rev. E 82(5):056408, 2010) showed that increasing the width (up to 1 mm) of the plasma increases the amplification surface and improves the gain zone properties. Up to 20 μJ could be extracted when seeding but the temporal duration and profile was not studied. Simulations show that the HOH is weakly amplified whereas most of the energy is within a long (several picoseconds) wake induced by the HOH (Al'miev et al. in Phys. Rev. Lett. 99(12):123902, 2007; Kim et al. in Phys. Rev. Lett. 104:053901, 2010). Amplified Spontaneous Emission (ASE) is also present in the output beam. Using the 1D Maxwell-Bloch code DeepOne (Oliva et al. in Phys. Rev. A 84(1):013811, 2011) we will show that fully coherent, wake and ASE-suppressed, 21.6 μJ, 80 fs pulse can be obtained when optimizing at the same time both the seed and the plasma conditions.

  14. Sensitivity Studies in Gyro-fluid Simulation

    NASA Astrophysics Data System (ADS)

    Ross, D. W.; Dorland, W.; Beer, M. A.; Hammett, G. W.

    1998-11-01

    Transport models [1] derived from gyrofluid simulation [2] have been successful in predicting general confinement scalings. Specific fluxes and turbulent spectra, however, can depend sensitively on the plasma configuration and profiles, particularly in experiments with transients. Here, we step back from initial studies on Alcator C-Mod [3] and DIII-D [4] to investigate the sensitivity of simulations to variations in density, temperature (and their gradients) of each plasma species. We discuss the role of electric field shear, and the construction of local transport models for experimental comparison. In accompanying papers [5] we investigate comparisons with the experiments. *Supported by USDOE Grants DE-FG03-95ER54296, and DE-AC02-76CHO3073. [1] M. Kotschenreuther et al., Phys. Plasmas 2, 2381 (1995). [2] M. A. Beer et al, Phys. Plasmas 2, 2687 (1995). [3] D. W. Ross et al., Transport Task Force, Atlanta, 1998. [4] R. V. Bravenec et al., in Proc. 25th EPS Conf. on Contr. Fusion and Plasma Phys., Prague (1998). [5] R. V. Bravenec et al. and W. L. Rowan et al., these proceedings.

  15. Elastic fields, dipole tensors, and interaction between self-interstitial atom defects in bcc transition metals

    NASA Astrophysics Data System (ADS)

    Dudarev, S. L.; Ma, Pui-Wai

    2018-03-01

    Density functional theory (DFT) calculations show that self-interstitial atom (SIA) defects in nonmagnetic body-centered-cubic (bcc) metals adopt strongly anisotropic configurations, elongated in the <111 > direction [S. Han et al., Phys. Rev. B 66, 220101 (2002), 10.1103/PhysRevB.66.220101; D. Nguyen-Manh et al., Phys. Rev. B 73, 020101 (2006), 10.1103/PhysRevB.73.020101; P. M. Derlet et al., Phys. Rev. B 76, 054107 (2007), 10.1103/PhysRevB.76.054107; S. L. Dudarev, Annu. Rev. Mater. Res. 43, 35 (2013), 10.1146/annurev-matsci-071312-121626]. Elastic distortions, associated with such anisotropic atomic structures, appear similar to distortions around small prismatic dislocation loops, although the extent of this similarity has never been quantified. We derive analytical formulas for the dipole tensors of SIA defects, which show that, in addition to the prismatic dislocation looplike character, the elastic field of a SIA defect also has a significant isotropic dilatation component. Using empirical potentials and DFT calculations, we parametrize dipole tensors of <111 > defects for all the nonmagnetic bcc transition metals. This enables a quantitative evaluation of the energy of elastic interaction between the defects, which also shows that in a periodic three-dimensional simple cubic arrangement of crowdions, long-range elastic interactions between a defect and all its images favor a <111 > orientation of the defect.

  16. Studies of giant magnetoresistance and interfacial structure in Cu/Co and Co/Re multilayers

    NASA Astrophysics Data System (ADS)

    Setty, Arun; Fernando, G.; Cooper, B. R.

    2003-03-01

    A study of giant magnetoresistance (GMR) in the Cu/Co [1]and Co/Re multilayer [2,3] systems is presented. The role of interface structure in such systems is significant, and is being investigated using an ab-initio based approach [4]. The role of intermixing [5], impurities and growth textures have been considered. Structural relaxation is taken into account using Hellman-Feynman and symmetry-based approaches. We find lattice spacings in agreement with experiment, energetically establish the favored growth textures and find results motivating the existence of the observed wavy interface in the Cu/Co system [6]. The transport properties of these multilayer systems will be studied using a theoretical model [7] incorporating material parameters obtained from the multiscale modeling approach we envisage. [1] S.S.P. Parkin, Z.G. Li, and D. J. Smith, Appl. Phys. Lett., 58, 2710-2712 (1991). [2] T. Charlton et al, Phys. Rev. B 63, 094404 (2001) [3] T. Charlton et al, Phys. Rev. B 59, 11897-11908 (1999) [4] C. Villagonzalo, A.K. Setty and B.R. Cooper, submitted to Phys. Rev. [5] J. Fassbender, R. Allenspach, and U. Durig. Surf. Sci., 383, L742-L748, (1997). [6] D.J. Larson et al, Appl. Phys. Lett., 73:1125-1127, (1998). [7] J. C. Slonczewski, Phys. Rev. B 39, 6995 (1989).

  17. Absolute Charge Exchange Cross Sections for ^3He^2+ Collisions with ^4He and H_2

    NASA Astrophysics Data System (ADS)

    Mawhorter, R. J.; Greenwood, J.; Smith, S. J.; Chutjian, A.

    2002-05-01

    The JPL charge exchange beam-line(J.B. Greenwood, et al., Phys. Rev A 63), 062707 (2001) was modified to increase the forward acceptance angle and enable the measurement of total charge-exchange cross sections for slow, light, highly-charged ion collisions with neutral targets(R. E. Olson and M. Kimura, J. Phys. B 15), 4231 (1982). Data are presented for single charge exchange cross sections for ^3He^2+ nuclei scattered by ^4He and H2 in the energy range 0.33-4.67 keV/amu. For both targets there is good agreement with Kusakabe, et al.(T. Kusakabe, et al., J. Phys. Soc. Japan 59), 1218 (1990). Angular collection is studied by a comparison with differential measurements(D. Bordenave-Montesquieu and R. Dagnac, J. Phys. B 27), 543 (1994), as well as with earlier JPL results(J.B. Greenwood, et al., Ap. J. 533), L175 (2000), ibid. 529, 605 (2000) using heavier projectiles and targets. This work was carried out at JPL/Caltech, and was supported through contract with NASA. RJM thanks the NRC for a Senior Associateship at JPL.

  18. EDITORIAL: Cluster issue on Heusler compounds and devices Cluster issue on Heusler compounds and devices

    NASA Astrophysics Data System (ADS)

    Felser, Claudia; Hillebrands, Burkard

    2009-04-01

    of the spin-Hall effect, spin-torque investigations and CPP GMR (current perpendicular plane giant magnetoresistance). Schneider et al have studied the Hall effect of laser ablated Co2(MnFe)Si thin films. Recently Inomata's group has reported on a high CPP GMR effect based on CFSA [19]. In this issue a theoretical study by Dai et al reports on the interfaces between CCFA and very thin chromium layers. Here the interface stays half-metallic which is a promising result regarding the realization of potential GMR devices. For spin-torque applications special requirements concerning the materials are necessary. Low damping constants, low magnetic moments and a perpendicular anisotropy are favourable properties. Ferrimagnetic Heusler compounds are candidates for low magnetic moments despite a high spin polarization and a high Curie temperature [20, 21]. Mn3Ga shows additionally a tetragonal distortion, which is favourable for perpendicular anisotropy [21]. The stability of Heusler compounds versus structural distortion is a well known phenomenon in shape memory alloys [22]. We hope this cluster of papers will inspire many researchers in the field of spintronics and motivate some of them to use these advanced materials for new devices. References [1] Heusler F 1903 Verh. Dtsch. Phys. Ges. 12 219 [2] de Groot R A, Müller F M, van Engen P G and Buschow K H J 1983 Phys. Rev. Lett. 50 2024 [3] Kübler J, Williams A R, Sommers C B 1983 Phys. Rev. B 28 1745 [4] Block T, Felser C and Jakob G 2003 J. Solid State Chem. 176 646 [5] Galanakis I, Mavropoulos Ph and Dederichs P H 2006 J. Phys. D: Appl. Phys. 39 765 [6] Kandpal H C, Fecher G H and Felser C 2007 J. Phys. D: Appl. Phys. 40 1507 [7] Wurmehl S, Fecher G H, Kandpal H C, Ksenofontov V, Felser C and Lin H J 2006 Appl. Phys. Lett. 86 032503 [8] Kämmerer S, Thomas A, Hütten A and Reiss G 2004 Appl. Phys. Lett. 85 79 [9] Yamato M, Marukame T, Ishikawa T, Matsuda K, Uemura T and Arita M 2006 J. Phys. D: Appl. Phys. 39 824 [10

  19. Correction: Spectroscopic characteristics of the OSIRIS near-backscattering crystal analyser spectrometer on the ISIS pulsed neutron source.

    PubMed

    Telling, Mark T F; Campbell, Stuart I; Engberg, Dennis; Martín Y Marero, David; Andersen, Ken H

    2016-03-21

    Correction for 'Spectroscopic characteristics of the OSIRIS near-backscattering crystal analyser spectrometer on the ISIS pulsed neutron source' by Mark T. F. Telling et al., Phys. Chem. Chem. Phys., 2005, 7, 1255-1261.

  20. Cheating in a Dental Practical Exam

    ERIC Educational Resources Information Center

    Currie, Wendy; Dracopoulos, Susie; Hendry, Graham

    2017-01-01

    There is increasing attention given to academic integrity across university education and dental schools are not immune to this problem (Andrews et al. J Dent Educ 71; 1027-1039, 2007; Ford & Hughes Eur J Dent Educ 16(1):e180-e186, 2012). While there has been an increasing concern about academic dishonesty in written exams and assignments,…

  1. Families of quantum fingerprinting protocols

    NASA Astrophysics Data System (ADS)

    Lovitz, Benjamin; Lütkenhaus, Norbert

    2018-03-01

    We introduce several families of quantum fingerprinting protocols to evaluate the equality function on two n -bit strings in the simultaneous message passing model. The original quantum fingerprinting protocol uses a tensor product of a small number of O (logn ) -qubit high-dimensional signals [H. Buhrman et al., Phys. Rev. Lett. 87, 167902 (2001), 10.1103/PhysRevLett.87.167902], whereas a recently proposed optical protocol uses a tensor product of O (n ) single-qubit signals, while maintaining the O (logn ) information leakage of the original protocol [J. M. Arazola and N. Lütkenhaus, Phys. Rev. A 89, 062305 (2014), 10.1103/PhysRevA.89.062305]. We find a family of protocols which interpolate between the original and optical protocols while maintaining the O (logn ) information leakage, thus demonstrating a tradeoff between the number of signals sent and the dimension of each signal. There has been interest in experimental realization of the recently proposed optical protocol using coherent states [F. Xu et al., Nat. Commun. 6, 8735 (2015), 10.1038/ncomms9735; J.-Y. Guan et al., Phys. Rev. Lett. 116, 240502 (2016), 10.1103/PhysRevLett.116.240502], but as the required number of laser pulses grows linearly with the input size n , eventual challenges for the long-time stability of experimental setups arise. We find a coherent state protocol which reduces the number of signals by a factor 1/2 while also reducing the information leakage. Our reduction makes use of a simple modulation scheme in optical phase space, and we find that more complex modulation schemes are not advantageous. Using a similar technique, we improve a recently proposed coherent state protocol for evaluating the Euclidean distance between two real unit vectors [N. Kumar et al., Phys. Rev. A 95, 032337 (2017), 10.1103/PhysRevA.95.032337] by reducing the number of signals by a factor 1/2 and also reducing the information leakage.

  2. Series of (2+1)-dimensional stable self-dual interacting conformal field theories

    NASA Astrophysics Data System (ADS)

    Cheng, Meng; Xu, Cenke

    2016-12-01

    Using the duality between seemingly different (2+1)-dimensional [(2 +1 )d ] conformal field theories (CFT) proposed recently [D. T. Son, Phys. Rev. X 5, 031027 (2015), 10.1103/PhysRevX.5.031027; M. A. Metlitski and A. Vishwanath, Phys. Rev. B 93, 245151 (2016), 10.1103/PhysRevB.93.245151; C. Wang and T. Senthil, Phys. Rev. X 6, 011034 (2015), 10.1103/PhysRevX.6.011034; C. Wang and T. Senthil, Phys. Rev. X 5, 041031 (2015), 10.1103/PhysRevX.5.041031; C. Wang and T. Senthil, Phys. Rev. B 93, 085110 (2016), 10.1103/PhysRevB.93.085110; C. Xu and Y.-Z. You, Phys. Rev. B 92, 220416 (2015), 10.1103/PhysRevB.92.220416; D. F. Mross et al., Phys. Rev. Lett. 117, 016802 (2016), 10.1103/PhysRevLett.117.016802; A. Karch and D. Tong, arXiv:1606.01893; N. Seiberg et al., arXiv:1606.01989; P.-S. Hsin and N. Seiberg, arXiv:1607.07457], we study a series of (2 +1 )d stable self-dual interacting CFTs. These CFTs can be realized (for instance) on the boundary of the 3 d bosonic topological insulator protected by U(1) and time-reversal symmetry (T ), and they remain stable as long as these symmetries are preserved. When realized as a boundary system, these CFTs can be driven into anomalous fractional quantum Hall states once T is broken. We demonstrate that the newly proposed dualities allow us to study these CFTs quantitatively through a controlled calculation, without relying on a large flavor number of matter fields. We also propose a numerical test for our results, which would provide strong evidence for the originally proposed duality between Dirac fermion and QED.

  3. Scaled experimental investigation of the moderation of auroral cyclotron emissions by background plasma

    NASA Astrophysics Data System (ADS)

    McConville, S. L.; Speirs, D. C.; Gillespie, K. M.; Phelps, A. D. R.; Cross, A. W.; Koepke, M. E.; Whyte, C. G.; Matheson, K.; Robertson, C. W.; Cairns, R. A.; Vorgul, I.; Bingham, R.; Kellett, B. J.; Ronald, K.

    2012-04-01

    generated was lower than with no plasma present. Plasma diagnostics established the plasma frequency on the order of 150-300MHz and electron density ranging from ~1014-1015m-3, whilst the cyclotron frequency of the electrons within the Penning trap was 5.87GHz giving fce/fpe ~19-40, comparable to the auroral density cavity. Numerical simulations coinciding with this part of the experimental research program are currently being carried out using the VORPAL code. Details of these simulations will be presented in a separate paper [Speirs et al] at this meeting. McConville SL et al 2008, Plasma Phys. Control. Fusion, 50, 074010 Ronald et al 2011, Plasma Phys. Control. Fusion, 53, 074015 Bingham R and Cairns RA, 2002, Phys. Scr., T98, 160-162 Ergun RE et al, 1998, Geophys. Res. Lett., 25, 2061 Gurnett DA et al, 1974, J. Geophys. Res., 79, 4227-4238 Cairns RA et al, 2011, Phys. Plasmas, 18, 022902 Gillespie KM et al, 2008, Plasma Phys. Control. Fusion, 50, 124038 Speirs et al 2010, Phys. Plasmas, 17, 056501 Vorgul et al 2011, Phys. Plasmas, 18, 056501 McConville SL et al 2011, Plasma Phys. Control. Fusion, 53, 124020

  4. Transforming Research and Clinical Knowledge in Traumatic Brain Injury

    DTIC Science & Technology

    2016-12-01

    Szuflita, N., Orman, J., and Schwab, K. (2010). Advancing integrated research in psychological health and traumatic brain injury: common data ele- ments...Szuflita N, Orman J, et al. Advancing Integrated Research in Psychological Health and Traumatic Brain Injury: Common Data Elements. Arch Phys Med Rehabil...R, Gleason T, et al. Advancing integrated research in psychological health and traumatic brain injury: common data elements. Arch Phys Med Rehabil

  5. Correction: The effect of recombination under short-circuit conditions on the determination of charge transport properties in nanostructured photoelectrodes.

    PubMed

    Villanueva-Cab, J; Anta, J A; Oskam, G

    2016-05-28

    Correction for 'The effect of recombination under short-circuit conditions on the determination of charge transport properties in nanostructured photoelectrodes' by J. Villanueva-Cab et al., Phys. Chem. Chem. Phys., 2016, 18, 2303-2308.

  6. High harmonic generation in a gas-filled hollow-core photonic crystal fiber

    NASA Astrophysics Data System (ADS)

    Heckl, O. H.; Baer, C. R. E.; Kränkel, C.; Marchese, S. V.; Schapper, F.; Holler, M.; Südmeyer, T.; Robinson, J. S.; Tisch, J. W. G.; Couny, F.; Light, P.; Benabid, F.; Keller, U.

    2009-10-01

    High harmonic generation (HHG) of intense infrared laser radiation (Ferray et al., J. Phys. B: At. Mol. Opt. Phys. 21:L31, 1988; McPherson et al., J. Opt. Soc. Am. B 4:595, 1987) enables coherent vacuum-UV (VUV) to soft-X-ray sources. In the usual setup, energetic femtosecond laser pulses are strongly focused into a gas jet, restricting the interaction length to the Rayleigh range of the focus. The average photon flux is limited by the low conversion efficiency and the low average power of the complex laser amplifier systems (Keller, Nature 424:831, 2003; Südmeyer et al., Nat. Photonics 2:599, 2008; Röser et al., Opt. Lett. 30:2754, 2005; Eidam et al., IEEE J. Sel. Top. Quantum Electron. 15:187, 2009) which typically operate at kilohertz repetition rates. This represents a severe limitation for many experiments using the harmonic radiation in fields such as metrology or high-resolution imaging. Driving HHG with novel high-power diode-pumped multi-megahertz laser systems has the potential to significantly increase the average photon flux. However, the higher average power comes at the expense of lower pulse energies because the repetition rate is increased by more than a thousand times, and efficient HHG is not possible in the usual geometry. So far, two promising techniques for HHG at lower pulse energies were developed: external build-up cavities (Gohle et al., Nature 436:234, 2005; Jones et al., Phys. Rev. Lett. 94:193, 2005) and resonant field enhancement in nanostructured targets (Kim et al., Nature 453:757, 2008). Here we present a third technique, which has advantages in terms of ease of HHG light extraction, transverse beam quality, and the possibility to substantially increase conversion efficiency by phase-matching (Paul et al., Nature 421:51, 2003; Ren et al., Opt. Express 16:17052, 2008; Serebryannikov et al., Phys. Rev. E (Stat. Nonlinear Soft Matter Phys.) 70:66611, 2004; Serebryannikov et al., Opt. Lett. 33:977, 2008; Zhang et al., Nat. Phys. 3

  7. Reply to "Comment on `Acoustical observation of bubble oscillations induced by bubble popping' "

    NASA Astrophysics Data System (ADS)

    Ding, Junqi

    2015-03-01

    We reported on the sound pressure generated by aqueous foam bursts in our paper [Ding et al., Phys. Rev. E 75, 041601 (2007), 10.1103/PhysRevE.75.041601]. Blanc et al., [Phys. Rev. E 91, 036401 (2015), 10.1103/PhysRevE.91.036401] found that sound from one of three mechanisms of bubble burst (the prepopping) actually results from an acausal artifact of the signal processing performed by their acquisition system which lies outside of its prescribed working frequency range. We examined the same hardware used in our paper and found that the frequency range is not the cause of the artifact. The prepopping sound was a result from a built-in finite impulse response filter of analog-to-digital converters in the Brüel & Kjær data acquisition system.

  8. Edge instability in incompressible planar active fluids

    NASA Astrophysics Data System (ADS)

    Nesbitt, David; Pruessner, Gunnar; Lee, Chiu Fan

    2017-12-01

    Interfacial instability is highly relevant to many important biological processes. A key example arises in wound healing experiments, which observe that an epithelial layer with an initially straight edge does not heal uniformly. We consider the phenomenon in the context of active fluids. Improving upon the approximation used by Zimmermann, Basan, and Levine [Eur. Phys. J.: Spec. Top. 223, 1259 (2014), 10.1140/epjst/e2014-02189-7], we perform a linear stability analysis on a two-dimensional incompressible hydrodynamic model of an active fluid with an open interface. We categorize the stability of the model and find that for experimentally relevant parameters, fingering instability is always absent in this minimal model. Our results point to the crucial role of density variation in the fingering instability in tissue regeneration.

  9. Comment on ‘Poynting flux in the neighbourhood of a point charge in arbitrary motion and radiative power losses’

    NASA Astrophysics Data System (ADS)

    Rowland, David R.

    2018-01-01

    Based on a calculation of the Poynting vector flux in the neighbourhood of an accelerating point charge, Singal (2016 Eur. J. Phys. 37 045210) has claimed that the instantaneous rate of energy radiated by the charge differs from the Larmor formula. It is argued in this comment that Singal’s proposed formula for the radiated power is physically untenable because it predicts a negative rate of energy loss in physically realisable situations. The cause of Singal’s erroneous conclusion is identified as being a failure to realise that the bound electromagnetic field energy of an accelerating charge differs by the Schott energy from the bound field energy of a charge moving at a constant velocity equal to the current velocity of the accelerating charge. References to the salient literature are provided.

  10. Hermann Hankel's "On the general theory of motion of fluids". An essay including an English translation of the complete Preisschrift from 1861

    NASA Astrophysics Data System (ADS)

    Villone, Barbara; Rampf, Cornelius

    2017-12-01

    The present is a companion paper to "A contemporary look at Hermann Hankel's 1861 pioneering work on Lagrangian fluid dynamics" by Frisch, Grimberg and Villone [Eur. Phys. J. H 42, 537-556 (2017)]. Here we present the English translation of the 1861 prize manuscript from Göttingen University "Zur allgemeinen Theorie der Bewegung der Flüssigkeiten" (On the general theory of the motion of the fluids) of Hermann Hankel (1839-1873), which was originally submitted in Latin and then translated into German by the Author for publication. We also provide the English translation of two important reports on the manuscript, one written by Bernhard Riemann and the other by Wilhelm Eduard Weber during the assessment process for the prize. Finally, we give a short biography of Hermann Hankel with his complete bibliography.

  11. On the calculation of line strengths, oscillator strengths and lifetimes for very large principal quantum numbers in hydrogenic atoms and ions by the McLean-Watson formula

    NASA Astrophysics Data System (ADS)

    Hey, J. D.

    2014-08-01

    As a sequel to an earlier study (Hey 2009 J. Phys. B: At. Mol. Opt. Phys. 42 125701), we consider further the application of the line strength formula derived by Watson (2006 J. Phys. B: At. Mol. Opt. Phys. 39 L291) to transitions arising from states of very high principal quantum number in hydrogenic atoms and ions (Rydberg-Rydberg transitions, n > 1000). It is shown how apparent difficulties associated with the use of recurrence relations, derived (Hey 2006 J. Phys. B: At. Mol. Opt. Phys. 39 2641) by the ladder operator technique of Infeld and Hull (1951 Rev. Mod. Phys. 23 21), may be eliminated by a very simple numerical device, whereby this method may readily be applied up to n ≈ 10 000. Beyond this range, programming of the method may entail greater care and complexity. The use of the numerically efficient McLean-Watson formula for such cases is again illustrated by the determination of radiative lifetimes and comparison of present results with those from an asymptotic formula. The question of the influence on the results of the omission or inclusion of fine structure is considered by comparison with calculations based on the standard Condon-Shortley line strength formula. Interest in this work on the radial matrix elements for large n and n‧ is related to measurements of radio recombination lines from tenuous space plasmas, e.g. Stepkin et al (2007 Mon. Not. R. Astron. Soc. 374 852), Bell et al (2011 Astrophys. Space Sci. 333 377), to the calculation of electron impact broadening parameters for such spectra (Watson 2006 J. Phys. B: At. Mol. Opt. Phys. 39 1889) and comparison with other theoretical methods (Peach 2014 Adv. Space Res. in press), to the modelling of physical processes in H II regions (Roshi et al 2012 Astrophys. J. 749 49), and the evaluation bound-bound transitions from states of high n during primordial cosmological recombination (Grin and Hirata 2010 Phys. Rev. D 81 083005, Ali-Haïmoud and Hirata 2010 Phys. Rev. D 82 063521, Ali

  12. Correction: Conceptual design of tetraazaporphyrin- and subtetraazaporphyrin-based functional nanocarbon materials: electronic structures, topologies, optical properties, and methane storage capacities.

    PubMed

    Belosludov, Rodion V; Rhoda, Hannah M; Zhdanov, Ravil K; Belosludov, Vladimir R; Kawazoe, Yoshiyuki; Nemykin, Victor N

    2017-08-02

    Correction for 'Conceptual design of tetraazaporphyrin- and subtetraazaporphyrin-based functional nanocarbon materials: electronic structures, topologies, optical properties, and methane storage capacities' by Rodion V. Belosludov et al., Phys. Chem. Chem. Phys., 2016, 18, 13503-13518.

  13. Giant Dipole Resonance in light and heavy nuclei beyond selfconsistent mean field theory

    NASA Astrophysics Data System (ADS)

    Krewald, Siegfried; Lyutorovich, Nikolay; Tselyaev, Victor; Speth, Josef; Gruemmer, Frank; Reinhard, Paul-Gerhard

    2012-10-01

    While bulk properties of stable nuclei are successfully reproduced by mean-field theories employing effective interactions, the dependence of the centroid energy of the electric giant dipole resonance on the nucleon number A is not. This problem is cured by considering many-particle correlations beyond mean-field theory, which we do within a selfconsistent generalization of the Quasiparticle Time Blocking Approximation [1,2]. The electric giant dipole resonances in ^16O, ^40Ca, and ^208Pb are calculated using two new Skyrme interactions. Perspectives for an extension to effective field theories[3] are discussed.[4pt] [1] V. Tselyaev et al., Phys.Rev.C75, 014315(2007).[0pt] [2] N. Lyutorovich et al., submitted to Phys.Rev.Lett.[0pt] [3] S. Krewald et al., Prog.Part.Nucl.Phys.67, 322(2012).

  14. Reply to "Comment on `Troublesome aspects of the Renyi-MaxEnt treatment' "

    NASA Astrophysics Data System (ADS)

    Plastino, A.; Rocca, M. C.; Pennini, F.

    2017-11-01

    This Reply is intended as a refutation of the preceding Comment [Oikonomou and Bagci, Phys. Rev. E 96, 056101 (2017), 10.1103/PhysRevE.96.056101] on our paper [Plastino et al., Phys. Rev. E 94, 012145 (2016)., 10.1103/PhysRevE.94.012145]. We show that the Tsallis probability distribution of our paper does not coincide with the Tsallis distribution studied by Oikonomou and Bagci. Consequently, their findings do not apply to our paper.

  15. Reply to "Comment on 'Troublesome aspects of the Renyi-MaxEnt treatment' ".

    PubMed

    Plastino, A; Rocca, M C; Pennini, F

    2017-11-01

    This Reply is intended as a refutation of the preceding Comment [Oikonomou and Bagci, Phys. Rev. E 96, 056101 (2017)10.1103/PhysRevE.96.056101] on our paper [Plastino et al., Phys. Rev. E 94, 012145 (2016).1539-375510.1103/PhysRevE.94.012145]. We show that the Tsallis probability distribution of our paper does not coincide with the Tsallis distribution studied by Oikonomou and Bagci. Consequently, their findings do not apply to our paper.

  16. Low-energy positron scattering by pyrimidine

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barbosa, Alessandra Souza; Pastega, Diego F.; Bettega, Márcio H. F., E-mail: bettega@fisica.ufpr.br

    2015-12-28

    This work reports elastic integral and differential cross sections for positron collisions with pyrimidine, for energies up to 20 eV. The cross sections were computed with the Schwinger multichannel method in the static plus polarization approximation. We also employed the Born closure procedure to account for the long range potential due to the permanent dipole moment of the molecule. Our results are compared with the experimental total cross section of Zecca et al. [J. Phys. B 43, 215204 (2010)], the experimental grand-total, quasi-elastic integral and differential cross section of Palihawadana et al. [Phys. Rev. A 88, 12717 (2013)]. We alsomore » compare our results with theoretical integral and differential cross sections obtained by Sanz et al. [Phys. Rev. A 88, 62704 (2013)] with the R-matrix and the independent atom model with screening-corrected additivity rule methods, and with the results computed by Franz and Gianturco [Phys. Rev. A 88, 042711 (2013)] using model correlation-polarization potentials. The agreement between the theory and the experiment is encouraging.« less

  17. Finite Forward Acceptance Angles for Single Electron Capture by ^3He^2+ Ions in He and H_2

    NASA Astrophysics Data System (ADS)

    Mawhorter, Rj; Greenwood, J.; Smith; Chutjian, A.

    2004-05-01

    Perhaps surprisingly, electron capture scattering angles of a few degrees or more are observed for slow ions impacting light targets. Gas cells must be designed with this in mind. Indeed the difference between small acceptance angle results(W.L. Nutt, et al., J. Phys. B 8), 1457 (1978) and the larger acceptance-angle studies of both Kusakabe, et al.(T. Kusakabe, et al., J. Phys. Soc. Japan 59), 1218 (1990) and our group at JPL (presented here; energy range 0.33-4.67 keV/amu) for ^3He^2+ in H2 can be ascribed to this effect. Olson and Kimura(R. E. Olson and M. Kimura, J. Phys. B 15), 4231 (1982) have modeled the problem theoretically. We use existing differential cross section data(D. Bordenave-Montesquieu and R. Dagnac, J. Phys. B 27), 543 1994) for both H_2/ D2 and ^4He targets to calculate realistic acceptance angles. The resulting small total cross section corrections provide reliable absolute results for these benchmark systems. This work was carried out at JPL/Caltech, and was supported through agreement with NASA.

  18. Study of methods to increase cluster/dislocation loop densities in electrodes

    NASA Astrophysics Data System (ADS)

    Yang, Xiaoling; Miley, George H.

    2009-03-01

    Recent research has developed a technique for imbedding ultra-high density deuterium ``clusters'' (50 to 100 atoms per cluster) in various metals such as Palladium (Pd), Beryllium (Be) and Lithium (Li). It was found the thermally dehydrogenated PdHx retained the clusters and exhibited up to 12 percent lower resistance compared to the virginal Pd samplesootnotetextA. G. Lipson, et al. Phys. Solid State. 39 (1997) 1891. SQUID measurements showed that in Pd these condensed matter clusters approach metallic conditions, exhibiting superconducting propertiesootnotetextA. Lipson, et al. Phys. Rev. B 72, 212507 (2005ootnotetextA. G. Lipson, et al. Phys. Lett. A 339, (2005) 414-423. If the fabrication methods under study are successful, a large packing fraction of nuclear reactive clusters can be developed in the electrodes by electrolyte or high pressure gas loading. This will provide a much higher low-energy-nuclear- reaction (LENR) rate than achieved with earlier electrodeootnotetextCastano, C.H., et al. Proc. ICCF-9, Beijing, China 19-24 May, 2002..

  19. Adaptive clustering procedure for continuous gravitational wave searches

    NASA Astrophysics Data System (ADS)

    Singh, Avneet; Papa, Maria Alessandra; Eggenstein, Heinz-Bernd; Walsh, Sinéad

    2017-10-01

    In hierarchical searches for continuous gravitational waves, clustering of candidates is an important post-processing step because it reduces the number of noise candidates that are followed up at successive stages [J. Aasi et al., Phys. Rev. Lett. 88, 102002 (2013), 10.1103/PhysRevD.88.102002; B. Behnke, M. A. Papa, and R. Prix, Phys. Rev. D 91, 064007 (2015), 10.1103/PhysRevD.91.064007; M. A. Papa et al., Phys. Rev. D 94, 122006 (2016), 10.1103/PhysRevD.94.122006]. Previous clustering procedures bundled together nearby candidates ascribing them to the same root cause (be it a signal or a disturbance), based on a predefined cluster volume. In this paper, we present a procedure that adapts the cluster volume to the data itself and checks for consistency of such volume with what is expected from a signal. This significantly improves the noise rejection capabilities at fixed detection threshold, and at fixed computing resources for the follow-up stages, this results in an overall more sensitive search. This new procedure was employed in the first Einstein@Home search on data from the first science run of the advanced LIGO detectors (O1) [LIGO Scientific Collaboration and Virgo Collaboration, arXiv:1707.02669 [Phys. Rev. D (to be published)

  20. Strike point splitting in the heat and particle flux profiles compared with the edge magnetic topology in a n = 2 resonant magnetic perturbation field at JET

    NASA Astrophysics Data System (ADS)

    Harting, D. M.; Liang, Y.; Jachmich, S.; Koslowski, R.; Arnoux, G.; Devaux, S.; Eich, T.; Nardon, E.; Reiter, D.; Thomsen, H.; EFDA contributors, JET

    2012-05-01

    At JET the error field correction coils can be used to generate an n = 1 or n = 2 magnetic perturbation field (Liang et al 2007 Plasma Phys. Control. Fusion 49 B581). Various experiments at JET have already been carried out to investigate the mitigation of ELMs by resonant magnetic perturbations (RMPs) (Liang et al 2010 Nucl. Fusion 50 025013, Liang et al 2011 Nucl. Fusion 51 073001). However, the typical formation of a secondary strike point (strike point splitting) by RMPs observed in other machines (Jakubowski et al 2010 Contrib. Plasma Phys. 50 701-7, Jakubowski et al 2004 Nucl. Fusion 44 S1-11, Nardon et al 2011 J. Nucl. Mater. 415 S914-7, Eich et al 2003 Phys. Rev. Lett. 91 195003, Evans et al 2007 J. Nucl. Mater. 363-365 570-4, Evans et al 2005 J. Phys.: Conf. Ser. 7 174-90, Watkins et al 2009 J. Nucl. Mater. 390-391 839-42) has never been observed at JET before. In this work we will present discharges where for the first time a strike point splitting by RMPs at JET has been observed. We will show that in these particular cases the strike point splitting matches the vacuum edge magnetic field topology. This is done by comparing heat and particle flux profiles on the outer divertor plate with the magnetic footprint pattern obtained by field line tracing. Further the evolution of the strike point splitting during the ramp up phase of the perturbation field and during a q95-scan is investigated, and it will be shown that the spontaneous appearance of the strike point splitting is only related to some geometrical effects of the toroidal asymmetric magnetic topology.

  1. Travelling-wave amplitudes as solutions of the phase-field crystal equation

    NASA Astrophysics Data System (ADS)

    Nizovtseva, I. G.; Galenko, P. K.

    2018-01-01

    The dynamics of the diffuse interface between liquid and solid states is analysed. The diffuse interface is considered as an envelope of atomic density amplitudes as predicted by the phase-field crystal model (Elder et al. 2004 Phys. Rev. E 70, 051605 (doi:10.1103/PhysRevE.70.051605); Elder et al. 2007 Phys. Rev. B 75, 064107 (doi:10.1103/PhysRevB.75.064107)). The propagation of crystalline amplitudes into metastable liquid is described by the hyperbolic equation of an extended Allen-Cahn type (Galenko & Jou 2005 Phys. Rev. E 71, 046125 (doi:10.1103/PhysRevE.71.046125)) for which the complete set of analytical travelling-wave solutions is obtained by the method (Malfliet & Hereman 1996 Phys. Scr. 15, 563-568 (doi:10.1088/0031-8949/54/6/003); Wazwaz 2004 Appl. Math. Comput. 154, 713-723 (doi:10.1016/S0096-3003(03)00745-8)). The general solution of travelling waves is based on the function of hyperbolic tangent. Together with its set of particular solutions, the general solution is analysed within an example of specific task about the crystal front invading metastable liquid (Galenko et al. 2015 Phys. D 308, 1-10 (doi:10.1016/j.physd.2015.06.002)). The influence of the driving force on the phase-field profile, amplitude velocity and correlation length is investigated for various relaxation times of the gradient flow. This article is part of the theme issue `From atomistic interfaces to dendritic patterns'.

  2. JPRS Report, Science & Technology, Japan, Powder Metallurgy Technology

    DTIC Science & Technology

    1988-12-13

    100 mO« 132 Hz i i i i -K H JL x’ c-p’an« (film) ! f • j 0 60 70 M TOO 90 1C Figure 3. Real and...necessary to develop a new manufacturing process focusing on the control of grain orientation. References 1. M . Okada, et al., Jpn. J. Appl. Phys. 27...Tc drops as the amount of Sr added is increased. References 1. M . Oda, et al., Jpn. J. Phys., 26, L804, 1987. 2. Z. Qi-rui, et al., Solid State

  3. Preface: phys. stat. sol. (a) 202/7

    NASA Astrophysics Data System (ADS)

    Pollak, Fred H.; Misiewicz, Jan; Sitarek, Piotr

    2005-05-01

    We have recently observed a growing interest in using the powerful technique of optical modulation spectroscopy. These applications are related mostly to the characterization of low dimensional semiconductor structures and devices based on them.The International Workshop on Modulation Spectroscopy of Semiconductor Structures (MS3) at the beginning of July 2004 gathered in Wrocaw (in the southwest part of Poland) almost 40 participants, half of them from abroad. The 8 invited and 16 contributed talks were presented by the leaders of research teams from the USA, Japan, Taiwan, Canada, Germany, France, the Netherlands, Sweden, Ireland, Russia, Lithuania and Poland. Part of the MS3 workshop was held at the Laboratory of Advanced Optical Spectroscopy, Institute of Physics, Wrocaw University of Technology, where discussions on technical matter of the modulation spectroscopy were carried out in a relaxing atmosphere over a cup of coffee.The topics of the MS3 workshop included: advantages of photoreflectance, electroreflectance, contactless electroreflectance, thermoreflectance, differential reflectance and wavelength-modulated surface photovoltage spectroscopy. The applications of the above methods to investigate transistor, diode and laser structures including VCSELs, low dimensional structures of both wings of the spectrum, i.e. wide band gap materials like GaN, AlGaN, ZnO and low band gap materials such as GaInN(Sb)As, InAs, InSb, and FeSi2 were demonstrated.It is our great pleasure to publish the most interesting of the MS3 workshop presentations in this issue of physica status solidi (a).The organizers acknowledge Wrocaw University of Technology, the Center of Exellence CEPHONA from the Institute of Electron Technology in Warsaw and the Polish Committee for Scientific Research for financial support of the workshop.

  4. Thermal solitons as revealed by the static structure factor

    NASA Astrophysics Data System (ADS)

    Gawryluk, Krzysztof; Brewczyk, Mirosław; Rzążewski, Kazimierz

    2017-04-01

    We study, within a framework of the classical fields approximation, the static structure factor of a weakly interacting Bose gas at thermal equilibrium. As in a recent experiment [R. Schley et al., Phys. Rev. Lett. 111, 055301 (2013), 10.1103/PhysRevLett.111.055301], we find that the thermal distribution of phonons in a three-dimensional Bose gas follows the Planck distribution. On the other hand we find a disagreement between the Planck and phonon (calculated just as for the bulk gas) distributions in the case of elongated quasi-one-dimensional systems. We attribute this discrepancy to the existence of spontaneous dark solitons [i.e., thermal solitons as reported in T. Karpiuk et al., Phys. Rev. Lett. 109, 205302 (2012), 10.1103/PhysRevLett.109.205302] in an elongated Bose gas at thermal equilibrium.

  5. Theoretical description of the mixed-field orientation of asymmetric-top molecules: A time-dependent study

    NASA Astrophysics Data System (ADS)

    Omiste, Juan J.; González-Férez, Rosario

    2016-12-01

    We present a theoretical study of the mixed-field-orientation of asymmetric-top molecules in tilted static electric field and nonresonant linearly polarized laser pulse by solving the time-dependent Schrödinger equation. Within this framework, we compute the mixed-field orientation of a state-selected molecular beam of benzonitrile (C7H5N ) and compare with the experimental observations [J. L. Hansen et al., Phys. Rev. A 83, 023406 (2011), 10.1103/PhysRevA.83.023406] and with our previous time-independent descriptions [J. J. Omiste et al., Phys. Chem. Chem. Phys. 13, 18815 (2011), 10.1039/c1cp21195a]. For an excited rotational state, we investigate the field-dressed dynamics for several field configurations as those used in the mixed-field experiments. The nonadiabatic phenomena and their consequences on the rotational dynamics are analyzed in detail.

  6. Ignition and pusher adiabat

    NASA Astrophysics Data System (ADS)

    Cheng, B.; Kwan, T. J. T.; Wang, Y. M.; Yi, S. A.; Batha, S. H.; Wysocki, F.

    2018-07-01

    In the last five years, large amounts of high quality data on inertial confinement fusion (ICF) experiments were produced at the National Ignition Facility (NIF). From this data we have significantly advanced our scientific understanding of the physics of thermonuclear (TN) ignition and identified critical issues that must be addressed to achieve a burning hotspot, such as implosion energetics, pusher adiabat, tamping effects, and confinement time. In this paper we present a review of recently developed TN ignition and implosion scaling theory (Cheng et al 2013 Phys. Rev. E 88 041101; Cheng et al 2014 Phys. Plasmas 21 10270) that characterizes the thermodynamic properties of the hotspot and the ignition criteria for ICF. We compare our theoretical predictions with NIF data and find good agreement between theory and experiments. We demonstrate the fundamental effects of the pusher adiabat on the energy partition between the cold shell and the hot deuterium–tritium (DT) gas, and thus on the integrated performance of ICF capsules. Theoretical analysis of NIF experiments (Cheng et al 2015 Phys. Plasmas 22 082704; Melvin et al 2015 Phys. Plasmas 22 022708; Cheng et al 2016 Phys. Plasmas 23 120702) and physical explanations of the discrepancies between theory, data, and simulations are presented. It is shown that the true experimental adiabat of the cold DT fuel can be inferred from neutron image data of a capsule implosion. We show that the ablator mix and preheat in the cold fuel can be estimated from the experimentally inferred hotspot mix. Finally, possible paths forward to reach higher yields at NIF implied by the theory are discussed.

  7. Full-potential KKR calculations for vacancies in Al : Screening effect and many-body interactions

    NASA Astrophysics Data System (ADS)

    Hoshino, T.; Asato, M.; Zeller, R.; Dederichs, P. H.

    2004-09-01

    We give ab initio calculations for vacancies in Al . The calculations are based on the generalized-gradient approximation in the density-functional theory and employ the all-electron full-potential Korringa-Kohn-Rostoker Green’s function method for point defects, which guarantees the correct embedding of the cluster of point defects in an otherwise perfect crystal. First, we confirm the recent calculated results of Carling [Phys. Rev. Lett. 85, 3862 (2000)], i.e., repulsion of the first-nearest-neighbor (1NN) divacancy in Al , and elucidate quantitatively the micromechanism of repulsion. Using the calculated results for vacancy formation energies and divacancy binding energies in Na , Mg , Al , and Si of face-centered-cubic, we show that the single vacancy in nearly free-electron systems becomes very stable with increasing free-electron density, due to the screening effect, and that the formation of divacancy destroys the stable electron distribution around the single vacancy, resulting in a repulsion of two vacancies on 1NN sites, so that the 1NN divacancy is unstable. Second, we show that the cluster expansion converges rapidly for the binding energies of vacancy agglomerates in Al . The binding energy of 13 vacancies consisting of a central vacancy and its 12 nearest neighbors, is reproduced within the error of 0.002eV per vacancy, if many-body interaction energies up to the four-body terms are taken into account in the cluster expansion, being compared with the average error (>0.1eV) of the glue models which are very often used to provide interatomic potentials for computer simulations. For the cluster expansion of the binding energies of impurities, we get the same convergence as that obtained for vacancies. Thus, the present cluster-expansion approach for the binding energies of agglomerates of vacancies and impurities in Al may provide accurate data to construct the interaction-parameter model for computer simulations which are strongly requested to study

  8. Comparison of Theoretically Predicted Electromagnetic Heavy Ion Cross Sections with CERN SPS and RHIC Data

    NASA Astrophysics Data System (ADS)

    Baltz, Anthony J.

    2002-10-01

    Theoretical predictions for a number of electromagnetically induced reactions have been compared with available ultrarelativistic heavy ion data. Calculations for three atomic process have been confronted with CERN SPS data. Theoretically predicted rates are in good agreement with data[1] for bound-electron positron pairs and ionization of single electron heavy ions. Furthermore, the exact solution of the semi-classical Dirac equation in the ultrarelativistic limit reproduces the perturbative scaling result seen in data[2] for continuum pairs (i.e. cross sections go as Z_1^2 Z_2^2). In the area of electromagnetically induced nuclear and hadronic physics, mutual Coulomb dissociation predictions are in good agreement with RHIC Zero Degree Calorimeter measurements[3], and calculations of coherent vector meson production accompanied by mutual Coulomb dissociation[4] are in good agreement with RHIC STAR data[5]. [1] H. F. Krause et al., Phys. Rev. Lett., 80, 1190 (1998). [2] C. R. Vane et al., Phys. Rev. A 56, 3682 (1997). [3] Mickey Chiu et al., Phys. Rev. Lett. 89, 012302 (2002). [4] Anthony J. Baltz, Spencer R. Klein, and Joakim Nystrand, Phys. Rev. Lett. 89, 012301 (2002). [5] C. Adler et al., STAR Collaboration, arXiv:nucl-ex/206004.

  9. X-ray computed microtomography of sea ice - comment on "A review of air-ice chemical and physical interactions (AICI): liquids, quasi-liquids, and solids in snow" by Bartels-Rausch et al. (2014)

    NASA Astrophysics Data System (ADS)

    Obbard, R. W.

    2015-07-01

    This comment addresses a statement made in "A review of air-ice chemical and physical interactions (AICI): liquids, quasi-liquids, and solids in snow" by Bartels-Rausch et al. (Atmos. Chem. Phys., 14, 1587-1633, doi:10.5194/acp-14-1587-2014, 2014). Here we rebut the assertion that X-ray computed microtomography of sea ice fails to reveal liquid brine inclusions by discussing the phases present at the analysis temperature.

  10. EDITORIAL: Special section on signal transduction Special section on signal transduction

    NASA Astrophysics Data System (ADS)

    Shvartsman, Stanislav

    2012-08-01

    , where a single molecule can participate in multiple types of interactions. Mathematical analysis of these models is discussed in the papers by Del Vecchio [8], Seaton and Krishnan [9], and Hatzimanikatis and colleagues [10]. Finally, all signaling systems are information processing devices. While this point is broadly accepted, there have been only a few attempts to apply information theory to experimental signaling systems. A review by Andre Levchenko and colleagues [11] provides a very clear introduction to information theory and its potential applications to signal transduction in cellular systems. References [1] Félix M-A 2012 Phys. Biol. 9 045001 [2] Oron E and Ivanova N 2012 Phys. Biol. 9 045002 [3] MacNamara A et al 2012 Phys. Biol. 9 045003 [4] Jensen K J and Janes K A 2012 Phys. Biol. 9 045004 [5] Zarnitsyna V and Zhu C 2012 Phys. Biol. 9 045005 [6] Rubinstein B et al 2012 Phys. Biol. 9 045006 [7] Frank T D et al 2012 Phys. Biol. 9 045007 [8] Del Vecchio D et al 2012 Phys. Biol. 9 045008 [9] Seaton D D and Krishnan J 2012 Phys. Biol. 9 045009 [10] Radivojevic A et al 2012 Phys. Biol. 9 045010 [11] Rhee A et al 2012 Phys. Biol. 9 045011

  11. Comment on "Propagation of a TE surface mode in a relativistic electron beam-quantum plasma system" [Phys. Lett. A 376 (2012) 169

    NASA Astrophysics Data System (ADS)

    Moradi, Afshin

    2016-07-01

    In a recent paper Abdel Aziz [Phys. Lett. A 376 (2012) 169] obtained the dispersion properties of TE surface modes propagating at the interface between a magnetized quantum plasma and vacuum in the Faraday configuration, where these TE surface waves are excited during the interaction of relativistic electron beam with magnetized quantum plasma. The present Comment points out that in the Faraday configuration the surface waves acquire both TM and TE components due to the cyclotron motion of electrons. Therefore, the TE surface waves cannot propagate on surface of the present system and the general dispersion relations for surface waves, derived by Abdel Aziz are incorrect.

  12. Direct longitudinal laser acceleration of electrons in free space

    NASA Astrophysics Data System (ADS)

    Carbajo, Sergio; Nanni, Emilio A.; Wong, Liang Jie; Moriena, Gustavo; Keathley, Phillip D.; Laurent, Guillaume; Miller, R. J. Dwayne; Kärtner, Franz X.

    2016-02-01

    Compact laser-driven accelerators are pursued heavily worldwide because they make novel methods and tools invented at national laboratories widely accessible in science, health, security, and technology [V. Malka et al., Principles and applications of compact laser-plasma accelerators, Nat. Phys. 4, 447 (2008)]. Current leading laser-based accelerator technologies [S. P. D. Mangles et al., Monoenergetic beams of relativistic electrons from intense laser-plasma interactions, Nature (London) 431, 535 (2004); T. Toncian et al., Ultrafast laser-driven microlens to focus and energy-select mega-electron volt protons, Science 312, 410 (2006); S. Tokita et al. Single-shot ultrafast electron diffraction with a laser-accelerated sub-MeV electron pulse, Appl. Phys. Lett. 95, 111911 (2009)] rely on a medium to assist the light to particle energy transfer. The medium imposes material limitations or may introduce inhomogeneous fields [J. R. Dwyer et al., Femtosecond electron diffraction: "Making the molecular movie,", Phil. Trans. R. Soc. A 364, 741 (2006)]. The advent of few cycle ultraintense radially polarized lasers [S. Carbajo et al., Efficient generation of ultraintense few-cycle radially polarized laser pulses, Opt. Lett. 39, 2487 (2014)] has ushered in a novel accelerator concept [L. J. Wong and F. X. Kärtner, Direct acceleration of an electron in infinite vacuum by a pulsed radially polarized laser beam, Opt. Express 18, 25035 (2010); F. Pierre-Louis et al. Direct-field electron acceleration with ultrafast radially polarized laser beams: Scaling laws and optimization, J. Phys. B 43, 025401 (2010); Y. I. Salamin, Electron acceleration from rest in vacuum by an axicon Gaussian laser beam, Phys. Rev. A 73, 043402 (2006); C. Varin and M. Piché, Relativistic attosecond electron pulses from a free-space laser-acceleration scheme, Phys. Rev. E 74, 045602 (2006); A. Sell and F. X. Kärtner, Attosecond electron bunches accelerated and compressed by radially polarized laser

  13. Al 1s-2p absorption spectroscopy of shock-wave heating and compression in laser-driven planar foil

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sawada, H.; Regan, S. P.; Radha, P. B.

    Time-resolved Al 1s-2p absorption spectroscopy is used to diagnose direct-drive, shock-wave heating and compression of planar targets having nearly Fermi-degenerate plasma conditions (T{sub e}{approx}10-40 eV, {rho}{approx}3-11 g/cm{sup 3}) on the OMEGA Laser System [T. R. Boehly et al., Opt. Commun. 133, 495 (1997)]. A planar plastic foil with a buried Al tracer layer was irradiated with peak intensities of 10{sup 14}-10{sup 15} W/cm{sup 2} and probed with the pseudocontinuum M-band emission from a point-source Sm backlighter in the range of 1.4-1.7 keV. The laser ablation process launches 10-70 Mbar shock waves into the CH/Al/CH target. The Al 1s-2p absorption spectramore » were analyzed using the atomic physic code PRISMSPECT to infer T{sub e} and {rho} in the Al layer, assuming uniform plasma conditions during shock-wave heating, and to determine when the heat front penetrated the Al layer. The drive foils were simulated with the one-dimensional hydrodynamics code LILAC using a flux-limited (f=0.06 and f=0.1) and nonlocal thermal-transport model [V. N. Goncharov et al., Phys. Plasmas 13, 012702 (2006)]. The predictions of simulated shock-wave heating and the timing of heat-front penetration are compared to the observations. The experimental results for a wide variety of laser-drive conditions and buried depths have shown that the LILAC predictions using f=0.06 and the nonlocal model accurately model the shock-wave heating and timing of the heat-front penetration while the shock is transiting the target. The observed discrepancy between the measured and simulated shock-wave heating at late times of the drive can be explained by the reduced radiative heating due to lateral heat flow in the corona.« less

  14. Zeeman relaxation of cold atomic iron and nickel in collisions with He3

    NASA Astrophysics Data System (ADS)

    Johnson, Cort; Newman, Bonna; Brahms, Nathan; Doyle, John M.; Kleppner, Daniel; Greytak, Thomas J.

    2010-06-01

    We have measured the ratio γ of the diffusion cross section to the angular momentum reorientation cross section in the colliding Fe-He3 and Ni-He3 systems. Nickel (Ni) and iron (Fe) atoms are introduced via laser ablation into a cryogenically cooled experimental cell containing cold (<1 K) He3 buffer gas. Elastic collisions rapidly cool the translational temperature of the ablated atoms to the He3 temperature. γ is extracted by measuring the decays of the atomic Zeeman sublevels. For our experimental conditions, thermal energy is comparable to the Zeeman splitting. As a result, thermal excitations between Zeeman sublevels significantly impact the observed decay. To determine γ accurately, we introduce a model of Zeeman-state dynamics that includes thermal excitations. We find γNi-3He=5×103 and γFe-3He⩽3×103 at 0.75 K in a 0.8-T magnetic field. These measurements are interpreted in the context of submerged shell suppression of spin relaxation, as studied previously in transition metals and rare-earth-metal atoms [C. I. Hancox, S. C. Doret, M. T. Hummon, R. V. Krems, and J. M. Doyle, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.94.013201 94, 013201 (2005); C. I. Hancox, S. C. Doret, M. T. Hummon, L. Luo, and J. M. Doyle, Nature (London)NATUAS0028-083610.1038/nature02938 431, 281 (2004); A. Buchachenko, G. Chaasiski, and M. Szczniak, Eur. Phys. J. DEPJDF61434-606010.1140/epjd/e2006-00263-3 45, 147 (2007)].

  15. Angular dependant micro-ESR characterization of a locally doped Gd3+:Al2O3 hybrid system for quantum applications

    NASA Astrophysics Data System (ADS)

    Wisby, I. S.; de Graaf, S. E.; Gwilliam, R.; Adamyan, A.; Kubatkin, S. E.; Meeson, P. J.; Tzalenchuk, A. Ya.; Lindstrom, T.

    Rare-earth doped crystals interfaced with superconducting quantum circuitry are an attractive platform for quantum memory and transducer applications. Here we present a detailed characterization of a locally implanted Gd3+ in Al2O3 system coupled to a superconducting micro-resonator, by performing angular dependent micro-electron-spin-resonance (micro-ESR) measurements at mK temperatures. The device is fabricated using a hard Si3N4 mask to facilitate a local ion-implantation technique for precision control of the dopant location. The technique is found not to degrade the internal quality factor of the resonators which remains above 105 (1). We find the measured angular dependence of the micro-ESR spectra to be in excellent agreement with the modelled Hamiltonian, supporting the conclusion that the dopant ions are successfully integrated into their relevant lattice sites whilst maintaining crystalline symmetries. Furthermore, we observe clear contributions from individual microwave field components of our micro-resonator, emphasising the need for controllable local implantation. 1 Wisby et al. Appl. Phys. Lett. 105, 102601 (2014)

  16. Do cosmological data rule out f (R ) with w ≠-1 ?

    NASA Astrophysics Data System (ADS)

    Battye, Richard A.; Bolliet, Boris; Pace, Francesco

    2018-05-01

    We review the equation of state (EoS) approach to dark sector perturbations and apply it to f (R ) gravity models of dark energy. We show that the EoS approach is numerically stable and use it to set observational constraints on designer models. Within the EoS approach we build an analytical understanding of the dynamics of cosmological perturbations for the designer class of f (R ) gravity models, characterized by the parameter B0 and the background equation of state of dark energy w . When we use the Planck cosmic microwave background temperature anisotropy, polarization, and lensing data as well as the baryonic acoustic oscillation data from SDSS and WiggleZ, we find B0<0.006 (95% C.L.) for the designer models with w =-1 . Furthermore, we find B0<0.0045 and |w +1 |<0.002 (95% C.L.) for the designer models with w ≠-1 . Previous analyses found similar results for designer and Hu-Sawicki f (R ) gravity models using the effective field theory approach [Raveri et al., Phys. Rev. D 90, 043513 (2014), 10.1103/PhysRevD.90.043513; Hu et al., Mon. Not. R. Astron. Soc. 459, 3880 (2016), 10.1093/mnras/stw775]; therefore this hints for the fact that generic f (R ) models with w ≠-1 can be tightly constrained by current cosmological data, complementary to solar system tests [Brax et al., Phys. Rev. D 78, 104021 (2008), 10.1103/PhysRevD.78.104021; Faulkner et al., Phys. Rev. D 76, 063505 (2007), 10.1103/PhysRevD.76.063505]. When compared to a w CDM fluid with the same sound speed, we find that the equation of state for f (R ) models is better constrained to be close to -1 by about an order of magnitude, due to the strong dependence of the perturbations on w .

  17. Tomography of atomic number and density of materials using dual-energy imaging and the Alvarez and Macovski attenuation model

    NASA Astrophysics Data System (ADS)

    Paziresh, M.; Kingston, A. M.; Latham, S. J.; Fullagar, W. K.; Myers, G. M.

    2016-06-01

    Dual-energy computed tomography and the Alvarez and Macovski [Phys. Med. Biol. 21, 733 (1976)] transmitted intensity (AMTI) model were used in this study to estimate the maps of density (ρ) and atomic number (Z) of mineralogical samples. In this method, the attenuation coefficients are represented [Alvarez and Macovski, Phys. Med. Biol. 21, 733 (1976)] in the form of the two most important interactions of X-rays with atoms that is, photoelectric absorption (PE) and Compton scattering (CS). This enables material discrimination as PE and CS are, respectively, dependent on the atomic number (Z) and density (ρ) of materials [Alvarez and Macovski, Phys. Med. Biol. 21, 733 (1976)]. Dual-energy imaging is able to identify sample materials even if the materials have similar attenuation coefficients at single-energy spectrum. We use the full model rather than applying one of several applied simplified forms [Alvarez and Macovski, Phys. Med. Biol. 21, 733 (1976); Siddiqui et al., SPE Annual Technical Conference and Exhibition (Society of Petroleum Engineers, 2004); Derzhi, U.S. patent application 13/527,660 (2012); Heismann et al., J. Appl. Phys. 94, 2073-2079 (2003); Park and Kim, J. Korean Phys. Soc. 59, 2709 (2011); Abudurexiti et al., Radiol. Phys. Technol. 3, 127-135 (2010); and Kaewkhao et al., J. Quant. Spectrosc. Radiat. Transfer 109, 1260-1265 (2008)]. This paper describes the tomographic reconstruction of ρ and Z maps of mineralogical samples using the AMTI model. The full model requires precise knowledge of the X-ray energy spectra and calibration of PE and CS constants and exponents of atomic number and energy that were estimated based on fits to simulations and calibration measurements. The estimated ρ and Z images of the samples used in this paper yield average relative errors of 2.62% and 1.19% and maximum relative errors of 2.64% and 7.85%, respectively. Furthermore, we demonstrate that the method accounts for the beam hardening effect in density (ρ) and

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Paziresh, M.; Kingston, A. M., E-mail: andrew.kingston@anu.edu.au; Latham, S. J.

    Dual-energy computed tomography and the Alvarez and Macovski [Phys. Med. Biol. 21, 733 (1976)] transmitted intensity (AMTI) model were used in this study to estimate the maps of density (ρ) and atomic number (Z) of mineralogical samples. In this method, the attenuation coefficients are represented [Alvarez and Macovski, Phys. Med. Biol. 21, 733 (1976)] in the form of the two most important interactions of X-rays with atoms that is, photoelectric absorption (PE) and Compton scattering (CS). This enables material discrimination as PE and CS are, respectively, dependent on the atomic number (Z) and density (ρ) of materials [Alvarez and Macovski,more » Phys. Med. Biol. 21, 733 (1976)]. Dual-energy imaging is able to identify sample materials even if the materials have similar attenuation coefficients at single-energy spectrum. We use the full model rather than applying one of several applied simplified forms [Alvarez and Macovski, Phys. Med. Biol. 21, 733 (1976); Siddiqui et al., SPE Annual Technical Conference and Exhibition (Society of Petroleum Engineers, 2004); Derzhi, U.S. patent application 13/527,660 (2012); Heismann et al., J. Appl. Phys. 94, 2073–2079 (2003); Park and Kim, J. Korean Phys. Soc. 59, 2709 (2011); Abudurexiti et al., Radiol. Phys. Technol. 3, 127–135 (2010); and Kaewkhao et al., J. Quant. Spectrosc. Radiat. Transfer 109, 1260–1265 (2008)]. This paper describes the tomographic reconstruction of ρ and Z maps of mineralogical samples using the AMTI model. The full model requires precise knowledge of the X-ray energy spectra and calibration of PE and CS constants and exponents of atomic number and energy that were estimated based on fits to simulations and calibration measurements. The estimated ρ and Z images of the samples used in this paper yield average relative errors of 2.62% and 1.19% and maximum relative errors of 2.64% and 7.85%, respectively. Furthermore, we demonstrate that the method accounts for the beam hardening effect in

  19. Antihydrogen Trapped in the ALPHA Experiment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bowe, Paul David

    2011-02-25

    In 2010 the ALPHA collaboration succeeded in trapping antihydrogen atoms for the first time.[i] Stored antihydrogen promises to be a unique tool for making high precision measurements of the structure of this first anti-atom. Achieving this milestone presented several substantial experimental challenges and this talk will describe how they were overcome. The unique design features of the ALPHA apparatus will be explained. These allow a high intensity positron source and an antiproton imaging detector similar to the one used in the ATHENA[iii] experiment to be combined with an innovative magnet design of the anti-atom trap. This seeks to minimise themore » perturbations to trapped charged particles which may cause particle loss and heating[iv]. The diagnostic techniques used to measure the diameter, number, density, and temperatures of both plasmas will be presented as will the methods developed to actively compress and cool of both plasma species to sizes and temperatures [v],[vi], [vii] where trapping attempts with a reasonable chance of success can be tried. The results of the successful trapping experiments will be outlined as well as some subsequent experiments to improve the trapping rate and storage time. [i] 'Trapped antihydrogen' G.B. Andresen et al., Nature 468, 673 (2010) [ii]'A Magnetic Trap for Antihydrogen Confinement' W. Bertsche et al., Nucl. Instr. Meth. Phys. Res. A566, 746 (2006) [iii] Production and detection of cold antihydrogen atoms M.Amoretti et al., Nature 419, 456 (2002). [iv]' Antihydrogen formation dynamics in a multipolar neutral anti-atom trap' G.B. Andresen et al., Phys. Lett. B 685, 141 (2010) [v]' Evaporative Cooling of Antiprotons to Cryogenic Temperatures', G.B. Andresen et al. Phys. Rev. Lett 105, 013003 (2010) [vi]'Compression of Antiproton Clouds for Antihydrogen Trapping' G. B. Andresen et al. Phys. Rev. Lett 100, 203401 (2008) [vii] 'Autoresonant Excitation of Antiproton Plasmas' G.B. Andresen et al., Phys. Rev. Lett. 106

  20. Antihydrogen Trapped in the ALPHA Experiment

    ScienceCinema

    Bowe, Paul David

    2017-12-18

    In 2010 the ALPHA collaboration succeeded in trapping antihydrogen atoms for the first time.[i] Stored antihydrogen promises to be a unique tool for making high precision measurements of the structure of this first anti-atom. Achieving this milestone presented several substantial experimental challenges and this talk will describe how they were overcome. The unique design features of the ALPHA apparatus will be explained. These allow a high intensity positron source and an antiproton imaging detector similar to the one used in the ATHENA[iii] experiment to be combined with an innovative magnet design of the anti-atom trap. This seeks to minimise the perturbations to trapped charged particles which may cause particle loss and heating[iv]. The diagnostic techniques used to measure the diameter, number, density, and temperatures of both plasmas will be presented as will the methods developed to actively compress and cool of both plasma species to sizes and temperatures [v],[vi], [vii] where trapping attempts with a reasonable chance of success can be tried. The results of the successful trapping experiments will be outlined as well as some subsequent experiments to improve the trapping rate and storage time. [i] 'Trapped antihydrogen' G.B. Andresen et al., Nature 468, 673 (2010) [ii]'A Magnetic Trap for Antihydrogen Confinement' W. Bertsche et al., Nucl. Instr. Meth. Phys. Res. A566, 746 (2006) [iii] Production and detection of cold antihydrogen atoms M.Amoretti et al., Nature 419, 456 (2002). [iv]' Antihydrogen formation dynamics in a multipolar neutral anti-atom trap' G.B. Andresen et al., Phys. Lett. B 685, 141 (2010) [v]' Evaporative Cooling of Antiprotons to Cryogenic Temperatures', G.B. Andresen et al. Phys. Rev. Lett 105, 013003 (2010) [vi]'Compression of Antiproton Clouds for Antihydrogen Trapping' G. B. Andresen et al. Phys. Rev. Lett 100, 203401 (2008) [vii] 'Autoresonant Excitation of Antiproton Plasmas' G.B. Andresen et al., Phys. Rev. Lett. 106, 025002

  1. Demystifying liver iron concentration measurements with MRI.

    PubMed

    Henninger, B

    2018-06-01

    This Editorial comment refers to the article: Non-invasive measurement of liver iron concentration using 3-Tesla magnetic resonance imaging: validation against biopsy. D'Assignies G, et al. Eur Radiol Nov 2017. • MRI is a widely accepted reliable tool to determine liver iron concentration. • MRI cannot measure iron directly, it needs calibration. • Calibration curves for 3.0T are rare in the literature. • The study by d'Assignies et al. provides valuable information on this topic. • Evaluation of liver iron overload should no longer be restricted to experts.

  2. New Particle Formation Events During 2013 in Hada Al Sham, Saudi-Arabia

    NASA Astrophysics Data System (ADS)

    Neitola, K.; Hyvärinen, A.; Lihavainen, H.; Alghamdi, M.; Hussein, T.; Khodeir, M.; Shehata, A.; Laaksonen, A. J.; Kulmala, M. T.

    2014-12-01

    clear growth, S is clear shrinkage, G + S is both growth and shrinkage and unclear is not clear in either way.ReferencesM. Dal Maso, et al. (2005). Bor. Env. Res., 10, 323-336.M. Kulmala, et al. (2006). Atmos. Chem. Phys., 6, 787-793. M. Kulmala, et al. (2013). Science, 336, 943-946.

  3. A plasma amplifier to combine multiple beams at NIF

    NASA Astrophysics Data System (ADS)

    Kirkwood, R. K.; Turnbull, D. P.; Chapman, T.; Wilks, S. C.; Rosen, M. D.; London, R. A.; Pickworth, L. A.; Colaitis, A.; Dunlop, W. H.; Poole, P.; Moody, J. D.; Strozzi, D. J.; Michel, P. A.; Divol, L.; Landen, O. L.; MacGowan, B. J.; Van Wonterghem, B. M.; Fournier, K. B.; Blue, B. E.

    2018-05-01

    Combining laser beams in a plasma is enabled by seeded stimulated Brillouin scattering which allows cross-beam energy transfer (CBET) to occur and re-distributes the energy between beams that cross with different incident angles and small differences in wavelength [Kirkwood et al. Phys. Plasmas 4, 1800 (1997)]. Indirect-drive implosions at the National Ignition Facility (NIF) [Haynam et al. Appl. Opt. 46, 3276-3303 (2007)] have controlled drive symmetry by using plasma amplifiers to transfer energy between beams [Kirkwood et al., Plasma Phys. Controlled Fusion 55, 103001 (2013); Lindl et al., Phys. Plasmas 21, 020501 (2014); and Hurricane et al. Nature 506, 343-348 (2014)]. In this work, we show that the existing models are well enough validated by experiments to allow a design of a plasma beam combiner that, once optimized, is expected to produce a pulse of light in a single beam with the energy greatly enhanced over existing sources. The scheme combines up to 61 NIF beams with 120 kJ of available energy into a single f/20 beam with a 1 ns pulse duration and a 351 nm wavelength by both resonant and off-resonance CBET. Initial experiments are also described that have already succeeded in producing a 4 kJ, 1 ns pulse in a single beam by combination of up to eight incident pump beams containing <1.1 kJ/beam, which are maintained near resonance for CBET in a plasma that is formed by 60 pre-heating beams [Kirkwood et al., Nat. Phys. 14, 80 (2018)].

  4. Nonlocality distillation and postquantum theories with trivial communication complexity.

    PubMed

    Brunner, Nicolas; Skrzypczyk, Paul

    2009-04-24

    We first present a protocol for deterministically distilling nonlocality, building upon a recent result of Forster et al. [Phys. Rev. Lett. 102, 120401 (2009)10.1103/PhysRevLett.102.120401]. Our protocol, which is optimal for two-copy distillation, works efficiently for a specific class of postquantum nonlocal boxes, which we term correlated nonlocal boxes. In the asymptotic limit, all correlated nonlocal boxes are distilled to the maximally nonlocal box of Popescu and Rohrlich. Then, taking advantage of a result of Brassard et al. [Phys. Rev. Lett. 96, 250401 (2006)10.1103/PhysRevLett.96.250401] we show that all correlated nonlocal boxes make communication complexity trivial, and therefore appear very unlikely to exist in nature. Astonishingly, some of these nonlocal boxes are arbitrarily close to the set of classical correlations. This result therefore gives new insight to the problem of why quantum nonlocality is limited.

  5. Estimation of shear viscosity based on transverse momentum correlations

    NASA Astrophysics Data System (ADS)

    STAR Collaboration; Sharma, Monika; STAR Collaboration

    2009-11-01

    Event anisotropy measurements at RHIC suggest the strongly interacting matter created in heavy ion collisions flows with very little shear viscosity. Precise determination of “shear viscosity-to-entropy” ratio is currently a subject of extensive study [S. Gavin and M. Abdel-Aziz, Phys. Rev. Lett. 97 (2006) 162302]. We present preliminary results of measurements of the evolution of transverse momentum correlation function with collision centrality of Au+Au interactions at s=200 GeV. We compare two differential correlation functions, namely inclusive [J. Adams et al. (STAR Collaboration), Phys. Rev. C 72 (2005) 044902] and a differential version of the correlation measure C˜ introduced by Gavin et al. [S. Gavin and M. Abdel-Aziz, Phys. Rev. Lett. 97 (2006) 162302; M. Sharma and C. A. Pruneau, Phys. Rev. C 79 (2009) 024905.]. These observables can be used for the experimental study of the shear viscosity per unit entropy.

  6. Brownian motion and entropic torque driven motion of domain walls in antiferromagnets

    NASA Astrophysics Data System (ADS)

    Yan, Zhengren; Chen, Zhiyuan; Qin, Minghui; Lu, Xubing; Gao, Xingsen; Liu, Junming

    2018-02-01

    We study the spin dynamics in antiferromagnetic nanowire under an applied temperature gradient using micromagnetic simulations on a classical spin model with a uniaxial anisotropy. The entropic torque driven domain-wall motion and the Brownian motion are discussed in detail, and their competition determines the antiferromagnetic wall motion towards the hotter or colder region. Furthermore, the spin dynamics in an antiferromagnet can be well tuned by the anisotropy and the temperature gradient. Thus, this paper not only strengthens the main conclusions obtained in earlier works [Kim et al., Phys. Rev. B 92, 020402(R) (2015), 10.1103/PhysRevB.92.020402; Selzer et al., Phys. Rev. Lett. 117, 107201 (2016), 10.1103/PhysRevLett.117.107201], but more importantly gives the concrete conditions under which these conclusions apply, respectively. Our results may provide useful information on the antiferromagnetic spintronics for future experiments and storage device design.

  7. The validation and preference among different EAM potentials to describe the solid-liquid transition of aluminum

    NASA Astrophysics Data System (ADS)

    Jiang, Yewei; Luo, Jie; Wu, Yongquan

    2017-06-01

    Empirical potential is vital to the classic atomic simulation, especially for the study of phase transitions, as well as the solid-interface. In this paper, we attempt to set up a uniform procedure for the validation among different potentials before the formal simulation study of phase transitions of metals. Two main steps are involved: (1) the prediction of the structures of both solid and liquid phases and their mutual transitions, i.e. melting and crystallization; (2) the prediction of vital thermodynamic (the equilibrium melting point at ambient pressure) and dynamic properties (the degrees of superheating and undercooling). We applied this procedure to the testing of seven published embedded-atom potentials (MKBA (Mendelev et al 2008 Philos. Mag. 88 1723), MFMP (Mishin et al 1999 Phys. Rev. B 59 3393), MDSL (Sturgeon and Laird 2000 Phys. Rev. B 62 14720), ZM (Zope and Mishin 2003 Phys. Rev. B 68 024102), LEA (Liu et al 2004 Model. Simul. Mater. Sci. Eng. 12 665), WKG (Winey et al 2009 Model. Simul. Mater. Sci. Eng. 17 055004) and ZJW (Zhou et al 2004 Phys. Rev. B 69 144113)) for the description of the solid-liquid transition of Al. All the predictions of structure, melting point and superheating/undercooling degrees were compared with the experiments or theoretical calculations. Then, two of them, MKBA and MDSL, were proven suitable for the study of the solid-liquid transition of Al while the residuals were unqualified. However, potential MKBA is more accurate to predict the structures of solid and liquid, while MDSL works a little better in the thermodynamic and dynamic predictions of solid-liquid transitions.

  8. Electron-impact excitation of Rydberg and valence electronic states of nitric oxide: II. Integral cross sections

    NASA Astrophysics Data System (ADS)

    Brunger, M. J.; Campbell, L.; Cartwright, D. C.; Middleton, A. G.; Mojarrabi, B.; Teubner, P. J. O.

    2000-02-01

    Integral cross sections (ICSs) for the excitation of 18 excited electronic states, and four composite excited electronic states, in nitric oxide (NO) have been determined for incident electron energies of 15, 20, 30, 40 and 50 eV. These ICSs were derived by extrapolating the respective measured differential cross sections (M J Brunger et al 2000 J. Phys. B: At. Mol. Opt. Phys. 33 783) to 0° and 180° and by performing the appropriate integration. Comparison of the present ICSs with the results of those determined in earlier optical emission measurements, and from theoretical calculations is made. At each incident energy considered, the current ICSs are also summed along with the corresponding elastic and rovibrational excitation ICSs from B Mojarrabi et al (1995 J. Phys. B: At. Mol. Opt. Phys. 28 487) and the ionization cross sections from Rapp and Englander-Golden (1965 J. Chem. Phys. 43 1464), to derive an estimate of the grand total cross sections (GTSs) for e- + NO scattering. The GTSs derived in this manner are compared with the results from independent linear transmission experiments and are found to be entirely consistent with them. The present excited electronic state ICS, and those for elastic and rovibrational excitation from Mojarrabi et al , appear to represent the first set of self-consistent cross sections for electron impact scattering from NO.

  9. Revised and Extended Analysis of the Odd Parity Configurations of Five-Times Ionized Xenon: Xe VI

    NASA Astrophysics Data System (ADS)

    Churilov, S. S.; Joshi, Y. N.

    Xenon spectra were recorded in the 300-1240 Å region on a 3 m and a 10.7 normal incidence spectrograph using a modified triggered spark source. The spectrum of five-times ionized xenon (Xe VI) was investigated. The previous analysis of the 5s25p,5s5p2, 5s25d and 5s26s configurations [V. Kaufman and J. Sugar, J. Opt. soc. Am. B4, 1924 (1987), A. Tauheed et al, J. Phys. B: At. Mol. Opt. Phys. 25, L561 (1992)] was confirmed. Three of the five levels of the 5p3 configurations [A. Tauheed et al. Div. At. Mol. Opt. Phys. (APS) & DAMP(CAP) joint meeting, Toronto, May 1995] and all the 5p3, 5s5p5d and 5s5p6s configurations levels [R. Sarmiento et al., J. Phys. B: At. Mol. Opt. Phys. 32, 2853 (1999)] have been found to be erroneous. 53 new lines have been classified in the Xe VI spectrum. Twenty nine additional levels belonging to the 5p3, 5f, 6p and 5s5p5d odd configurations have been established. Hartree-Fock calculations with relativistic corrections (HFR) and least-square-fitted calculations (LSF) were carried out to interpret the spectrum.

  10. The properties of borderlines in discontinuous conservative systems

    NASA Astrophysics Data System (ADS)

    Wang, X.-M.; Fang, Z.-J.

    2006-02-01

    The properties of the set of borderline images in discontinuous conservative systems are commonly investigated. The invertible system in which a stochastic web was found in 1999 is re-discussed here. The result shows that the set of images of the borderline actually forms the same stochastic web. The web has two typical local fine structures. Firstly, in some parts of the web the borderline crosses the manifold of hyperbolic points so that the chaotic diffusion is damped greatly; secondly, in other parts of phase space many holes and elliptic islands appear in the stochastic layer. This local structure shows infinite self-similarity. The noninvertible system in which the so-called chaotic quasi-attractor was found in [X.-M. Wang et al., Eur. Phys. J. D 19, 119 (2002)] is also studied here. The numerical investigation shows that such a chaotic quasi-attractor is confined by the preceding lower order images of the borderline. The mechanism of this confinement is revealed: a forbidden zone exists that any orbit can not visit, which is the sub-phase space of one side of the first image of the borderline. Each order of the images of the forbidden zone can be qualitatively divided into two sub-phase regions: one is the so-called escaping region that provides the orbit with an escaping channel, the other is the so-called dissipative region where the contraction of phase space occurs.

  11. Systematization of α-decaying nuclei based on shell structures: The case of even-odd nuclei

    NASA Astrophysics Data System (ADS)

    Yarman, Tolga; Zaim, Nimet; Yarman, O.; Kholmetskii, Alexander; Arık, Metin

    2017-01-01

    Previously, we provided a novel systematization of α-decaying even-even nuclei starting with the classically adopted mechanism (Yarman et al., Eur. Phys. J. A 52, 140 (2016)). The decay half-life of an α-decaying nucleus was framed so that i) the α-particle is taken at the outset to be born inside the parent nucleus with a given probability, ii) where it then keeps on bouncing off of the barrier of the parent nucleus till iii) it finally tunnels through the barrier. Knowing beforehand the measured decay half-life, we have taken into consideration, as a parameter, the probability of the α-particle being first born within the parent before it is emitted. We thence developed a scaffold based on shell properties of families composed of alike even-even nuclei. Nevertheless, our model allows us to incorporate any α-decaying nuclei, and along this line, we present a follow-up systematization of even-odd nuclei, with cases of odd-even and odd-odd α-decaying nuclei pending to be considered in a separate contribution. Notwithstanding, we make an effort herein to expand our approach to investigate the effect of "pairing" ( e.g., when a number of nucleons in the given nucleus becomes an even number, instead of the initial odd number, due to the addition of at least one neutron). Our results show that "pairing", as expected, definitely increases the stability of the given nucleus.

  12. Modeling of waiting times and price changes in currency exchange data

    NASA Astrophysics Data System (ADS)

    Repetowicz, Przemysław; Richmond, Peter

    2004-11-01

    A theory which describes the share price evolution at financial markets as a continuous-time random walk (Physica A 287 (2000) 468, Physica A 314 (2002) 749, Eur. Phys. J. B 27 (2002) 273, Physica A 376 (2000) 284) has been generalized in order to take into account the dependence of waiting times t on price returns x. A joint probability density function (pdf) φ(x,t) which uses the concept of a Lévy stable distribution is worked out. The theory is fitted to high-frequency US $/Japanese Yen exchange rate and low-frequency 19th century Irish stock data. The theory has been fitted both to price return and to waiting time data and the adherence to data, in terms of the χ2 test statistic, has been improved when compared to the old theory.

  13. Agent-based model for the h-index - exact solution

    NASA Astrophysics Data System (ADS)

    Żogała-Siudem, Barbara; Siudem, Grzegorz; Cena, Anna; Gagolewski, Marek

    2016-01-01

    Hirsch's h-index is perhaps the most popular citation-based measure of scientific excellence. In 2013, Ionescu and Chopard proposed an agent-based model describing a process for generating publications and citations in an abstract scientific community [G. Ionescu, B. Chopard, Eur. Phys. J. B 86, 426 (2013)]. Within such a framework, one may simulate a scientist's activity, and - by extension - investigate the whole community of researchers. Even though the Ionescu and Chopard model predicts the h-index quite well, the authors provided a solution based solely on simulations. In this paper, we complete their results with exact, analytic formulas. What is more, by considering a simplified version of the Ionescu-Chopard model, we obtained a compact, easy to compute formula for the h-index. The derived approximate and exact solutions are investigated on a simulated and real-world data sets.

  14. Study of Various Types of Resonances within the Phonon Damping Model

    NASA Astrophysics Data System (ADS)

    Dang, Nguyen Dinh

    2001-10-01

    The main successes of the Phonon Damping Model (PDM)(N. Dinh Dang and A. Arima, Phys. Rev. Lett. 80), 4145 (1998); Nucl. Phys. A 636, 427 (1998); N. Dinh Dang, K. Tanabe, and A. Arima, Phys. Rev. C 58, 3374 (1998). are presented in the description of: 1) the giant dipole resonance (GDR) in highly excited nuclei, 2) the double giant dipole resonance (DGDR) and multiple phonon resonances, 3) the Gamow-Teller resonance (GTR), and 4) the damping of pygmy dipole resonance (PDR) in neutron-rich nuclei. The analyses of results of numerical calculations are discussed in comparison with the experimental systematics on i) the width and the shape of the GDR at finite temperature ^1,(N. Dinh Dang et al., Phys. Rev. C 61), 027302 (2000). and angular momentum(N. Dinh Dang, Nucl. Phys. A 687), 261c (2001). for tin isotopes , ii) the electromagnetic cross sections of DGDR for ^136Xe and ^208Pb on a lead target at relativistic energies(N. Dinh Dang, V. Kim Au, and A. Arima, Phys. Rev. Lett. 85), 1827 (2000)., iii) the strength function of GTR(N. Dinh Dang, T. Suzuki, and A. Arima, Preprint RIKEN-AF-NF 377 (2000), submitted.), and iv) the PDR in oxygen and calcium isotopes(N. Dinh Dang et al., Phys. Rev. C 63), 044302 (2001)..

  15. Upper bound on three-tangles of reduced states of four-qubit pure states

    NASA Astrophysics Data System (ADS)

    Sharma, S. Shelly; Sharma, N. K.

    2017-06-01

    Closed formulas for upper bounds on three-tangles of three-qubit reduced states in terms of three-qubit-invariant polynomials of pure four-qubit states are obtained. Our results offer tighter constraints on total three-way entanglement of a given qubit with the rest of the system than those used by Regula et al. [Phys. Rev. Lett. 113, 110501 (2014), 10.1103/PhysRevLett.113.110501 and Phys. Rev. Lett. 116, 049902(E) (2016)], 10.1103/PhysRevLett.116.049902 to verify monogamy of four-qubit quantum entanglement.

  16. High-density carbon ablator ignition path with low-density gas-filled rugby hohlraum

    NASA Astrophysics Data System (ADS)

    Amendt, Peter; Ho, Darwin D.; Jones, Ogden S.

    2015-04-01

    A recent low gas-fill density (0.6 mg/cc 4He) cylindrical hohlraum experiment on the National Ignition Facility has shown high laser-coupling efficiency (>96%), reduced phenomenological laser drive corrections, and improved high-density carbon capsule implosion symmetry [Jones et al., Bull. Am. Phys. Soc. 59(15), 66 (2014)]. In this Letter, an ignition design using a large rugby-shaped hohlraum [Amendt et al., Phys. Plasmas 21, 112703 (2014)] for high energetics efficiency and symmetry control with the same low gas-fill density (0.6 mg/cc 4He) is developed as a potentially robust platform for demonstrating thermonuclear burn. The companion high-density carbon capsule for this hohlraum design is driven by an adiabat-shaped [Betti et al., Phys. Plasmas 9, 2277 (2002)] 4-shock drive profile for robust high gain (>10) 1-D ignition performance and large margin to 2-D perturbation growth.

  17. Influence of the Renner-Teller Coupling in CO+H Collision Dynamics

    NASA Astrophysics Data System (ADS)

    Ndengue, Steve Alexandre; Dawes, Richard

    2017-06-01

    Carbon monoxide is after molecular hydrogen the second most abundant molecule in the universe and an important molecule for processes occurring in the atmosphere, hydrocarbon combustion and the interstellar medium. The rate coefficients of CO in collision with dominant species like H, H_2, He, etc are necessary to understand the CO emission spectrum or to model combustion chemistry processes. The inelastic scattering of CO with H has been intensively studied theoretically in the past decades,^1 mostly using the so-called WKS PES^6 developed by Werner et al. or recently a modified version by Song et al.^2 Though the spectroscopic agreement of the WKS surface with experiment is quite good, so far the studies of scattering dynamics have neglected coupling to an electronic excited state. We present new results on a set of HCO surfaces of the ground and the excited Renner-Teller coupled electronic states^3 with the principal objective of studying the influence of the Renner-Teller coupling on the inelastic scattering of CO+H. Our calculations done using the MCTDH^4 algorithm in the 0-2 eV energy range allow evaluation of the contribution of the Renner-Teller coupling on the rovibrationally inelastic scattering and discuss the relevance and reliability of the calculations. References:} 1. N. Balakrishnan, M. Yan and A. Dalgarno, Astrophys. J. 568, 443 (2002); B.C. Shepler et al, Astron. & Astroph. 475, L15 (2007); L. Song et al, J. Chem. Phys. 142, 204303 (2015); K.M. Walker et al, Astroph. J. 811, 27 (2015). 2. L. Song et al, Astrophys. J. 813, 96 (2015). 3. H.-M. Keller et al, J. Chem. Phys. 105, 4983 (1996). 4. S. Ndengue, R. Dawes and H. Guo, J. Chem. Phys. 144, 244301 (2016). 5. M.H. Beck et al., Phys. Rep. 324, 1 (2000).

  18. Communication: The absolute shielding scales of oxygen and sulfur revisited

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Komorovsky, Stanislav; Repisky, Michal; Malkin, Elena

    2015-03-07

    We present an updated semi-experimental absolute shielding scale for the {sup 17}O and {sup 33}S nuclei. These new shielding scales are based on accurate rotational microwave data for the spin–rotation constants of H{sub 2}{sup 17}O [Puzzarini et al., J. Chem. Phys. 131, 234304 (2009)], C{sup 17}O [Cazzoli et al., Phys. Chem. Chem. Phys. 4, 3575 (2002)], and H{sub 2}{sup 33}S [Helgaker et al., J. Chem. Phys. 139, 244308 (2013)] corrected both for vibrational and temperature effects estimated at the CCSD(T) level of theory as well as for the relativistic corrections to the relation between the spin–rotation constant and the absolutemore » shielding constant. Our best estimate for the oxygen shielding constants of H{sub 2}{sup 17}O is 328.4(3) ppm and for C{sup 17}O −59.05(59) ppm. The relativistic correction for the sulfur shielding of H{sub 2}{sup 33}S amounts to 3.3%, and the new sulfur shielding constant for this molecule is 742.9(4.6) ppm.« less

  19. Surface Layering Near Room Temperature in a Nonmetallic Liquid

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, Sudeshna; Stripe, Benjamin; Shively, Patrick; Evmenenko, Geunnadi; Dutta, Pulak; Ehrlich, Steven; Mo, Haiding

    2009-03-01

    Oscillatory density profiles (layers) have been observed at the free surfaces of many liquid metals at and above room temperature [1]. A surface-layered state has been previously reported only in one dielectric liquid, tetrakis(2-ethylhexoxy)silane (TEHOS), and only at lower temperatures [2]. We have used x-ray reflectivity to study a molecular liquid, pentaphenyl trimethyl trisiloxane. Below T˜ 267K (well above the freezing point for this liquid), density oscillations appear at the surface. This liquid has a higher Tc (˜1200K) than TEHOS (˜950K), so that layers appear at T/Tc 0.2 in both cases. Our results indicate that surface order is a universal phenomenon in both metallic and dielectric liquids, and that the underlying physics is likely to be the same since layers always appear at T<˜0.2Tc as theoretically predicted [3] [3pt] REFERENCES: [0pt] [1]. e.g. O. M. Magnussen et al., Phys. Rev. Lett. 74, 4444 (1995) [0pt] [2]. H. Mo et al. Phys. Rev. Lett. 96, 096107 (2006); Phys. Rev. B 76, 024206 (2007) [0pt] [3]. e.g. E. Chac'on et al., Phys. Rev. Lett. 87, 166101 (2001)

  20. OSB as substrate for engineered wood flooring

    Treesearch

    Costel Barbuta; Pierre Blanchet; Alain Cloutier; Vikram Yadama; Eini Lowell

    2012-01-01

    Oriented strand board (OSB) is a commodity product subject to market fluctuation. Development of a specialty OSB could lead to a better, and more stable, market segment for OSB. It was demonstrated in a previous study (Barbuta et al. in Eur. 1. Wood Prod. 2010), that OSB may be designed to obtain a high bending modulus of elasticity in the parallel direction, close to...

  1. Shear Bond Strength of Metal Brackets to Zirconia Conditioned with Various Primer-Adhesive Systems

    DTIC Science & Technology

    2016-07-01

    Reynolds, 1979 ). Bonding orthodontic brackets to ceramic restorative materials poses a unique challenge. Abu et al. measured the strength between...forth by Reynolds and 34 others (Reynolds, 1979 ). The pertinent question is the following: should brackets be chemically bonded to zirconia...conditioned with a new silane coupling agent. Eur J Orthod. 2013 Feb;35(1):103-9. 40 Giannini M, Soares CJ, de Carvalho RM. Ultimate tensile

  2. Synthesizing (ZrAl3 + AlN)/Mg-Al composites by a 'matrix exchange' method

    NASA Astrophysics Data System (ADS)

    Gao, Tong; Li, Zengqiang; Hu, Kaiqi; Han, Mengxia; Liu, Xiangfa

    2018-06-01

    A method named 'matrix exchange' to synthesize ZrAl3 and AlN reinforced Mg-Al composite was developed in this paper. By inserting Al-10ZrN master alloy into Mg matrix and reheating the cooled ingot to 550 °C, Al and Mg atoms diffuse to the opposite side. As a result, liquid melt occurs once the interface areas reach to proper compositions. Then dissolved Al atoms react with ZrN, leading to the in-situ formation of ZrAl3 and AlN particles, while the Al matrix is finally replaced by Mg. This study provides a new insight for preparing Mg composites.

  3. EPR study of chromium-doped forsterite crystals: Cr3+( M1) with associated trivalent ions Al3+ and Sc3+

    NASA Astrophysics Data System (ADS)

    Ryabov, I. D.

    2012-10-01

    Electron paramagnetic resonance (EPR) study of single crystals of forsterite co-doped with chromium and scandium has revealed, apart from the known paramagnetic centers Cr3+( M1) and Cr3+( M1)- V_{{{{Mg}}^{2 + } }} ( M2) (Ryabov in Phys Chem Miner 38:177-184, 2011), a new center Cr3+( M1)- V_{{{{Mg}}^{2 + } }} ( M2)-Sc3+ formed by a Cr3+ ion substituting for Mg2+ at the M1 structural position with a nearest-neighbor Mg2+ vacancy at the M2 position and a Sc3+ ion presumably at the nearest-neighbor M1 position. For this center, the conventional zero-field splitting parameters D and E and the principal g values have been determined as follows: D = 33,172(29) MHz, E = 8,482(13) MHz, g = [1.9808(2), 1.9778(2), 1.9739(2)]. The center has been compared with the known ion pair Cr3+( M1)-Al3+ (Bershov et al. in Phys Chem Miner 9:95-101, 1983), for which the refined EPR data have been obtained. Based on these data, the known sharp M1″ line at 13,967 cm-1 (with the splitting of 1.8 cm-1), observed in low-temperature luminescence spectra of chromium-doped forsterite crystals (Glynn et al. in J Lumin 48, 49:541-544, 1991), has been ascribed to the Cr3+( M1)-Al3+ center. It has been found that the concentration of the new center increases from 0 up to 4.4 × 1015 mg-1, whereas that of the Cr3+( M1) and Cr3+( M1)- V_{{{{Mg}}^{2 + } }} ( M2) centers quickly decreases from 7.4 × 1015 mg-1 down to 3 × 1015 mg-1 and from 2.7 × 1015 mg-1 down to 0.5 × 1015 mg-1, i.e., by a factor of 2.5 and 5.4, respectively, with an increase of the Sc content from 0 up to 0.22 wt % (at the same Cr content 0.25 wt %) in the melt. When the Sc content exceeds that of Cr, the concentration of the new center decreases most likely due to the formation of the Sc3+( M1)- V_{{{{Mg}}^{2 + } }} ( M2)-Sc3+ complex instead of the Cr3+( M1)- V_{{{{Mg}}^{2 + } }} ( M2)-Sc3+ center. The formation of such ordered neutral complex is in agreement with the experimental results, concerning the incorporation of Sc

  4. PREFACE: Graphene Graphene

    NASA Astrophysics Data System (ADS)

    Singleton, John; Ferry, David K.

    2009-08-01

    , recent studies have shown that a high K dielectric solvent screens the impurities for room temperature transport in graphene, giving what is probably the intrinsic, phonon limited mobility at room temperature; this discovery and an analysis of the data form part of the article by Shishir and Ferry [7]. Continuing in the same vein, elsewhere Boukhvalov and Katsnelson [8] discuss chemical functionalization of graphene and Mucha-Kruczyński et al [9] covers the influence of the substrate. Finally, graphene has been referred to (somewhat optimistically!) as the 'mother of all carbon-based systems' [1]; graphite is a stack of graphene layers, whilst buckyballs and carbon nanotubes are wrapped-up and rolled-up graphene, respectively. Consequently, and following the discovery of graphene, there has been something of an experimental push to show that related physics may occur in graphite [10] and in organic conductors and other materials where the layers are very weakly coupled [11]; such phenomena had been expected by theoreticians for some years [11]. With this in mind, the article by Yaguchi and Singleton [12] reviews some of the field-induced states in graphite, in the hope that further cross-fertilization between graphene and its bulk relatives [10, 11] can occur. We hope that readers will enjoy these additions to the body of work that represents our understanding of graphene. References [1] Castro Neto A H et al 2006 Phys. World (November) p33 [2] Castro Neto A H et al 2009 Rev. Mod. Phys. 81 109 [3] Shishir R S and Ferry D K 2009 J. Phys.: Condens. Matter 21 344201 [4] Peres N M R et al 2009 J. Phys.: Condens. Matter 21 344202 [5] Huang L et al 2009 J. Phys.: Condens. Matter 21 344203 [6] Sun Q-f and Xie X C 2009 J. Phys.: Condens. Matter 21 344204 [7] Shishir R S and Ferry D K 2009 J. Phys.: Condens. Matter 21 232204 [8] Boukhvalov D W and Katsnelson M I 2009 J. Phys.: Condens. Matter 21 344205 [9] Mucha-Kruczyński M et al 2009 J. Phys.: Condens. Matter 21 344206 [10

  5. A non-linear 4-wave resonant model for non-perturbative fast ion interactions with Alfv'enic modes in burning plasmas

    NASA Astrophysics Data System (ADS)

    Zonca, Fulvio; Chen, Liu

    2007-11-01

    We adopt the 4-wave modulation interaction model, introduced by Chen et al [1] for analyzing modulational instabilities of the radial envelope of Ion Temperature Gradient driven modes in toroidal geometry, extending it to the modulations on the fast particle distribution function due to nonlinear Alfv'enic mode dynamics, as proposed in Ref. [2]. In the case where the wave-particle interactions are non-perturbative and strongly influence the mode evolution, as in the case of Energetic Particle Modes (EPM) [3], radial distortions (redistributions) of the fast ion source dominate the mode nonlinear dynamics. In this work, we show that the resonant particle motion is secular with a time-scale inversely proportional to the mode amplitude [4] and that the time evolution of the EPM radial envelope can be cast into the form of a nonlinear Schr"odinger equation a la Ginzburg-Landau [5]. [1] L. Chen et al, Phys. Plasmas 7 3129 (2000) [2] F. Zonca et al, Theory of Fusion Plasmas (Bologna: SIF) 17 (2000) [3] L. Chen, Phys. Plasmas 1, 1519 (1994).[4] F. Zonca et al, Nucl. Fusion 45 477 (2005) [5] F. Zonca et al, Plasma Phys. Contr. Fusion 48 B15 (2006)

  6. Interaction of Fast Ions with Global Plasma Modes in the C-2 Field Reversed Configuration Experiment

    NASA Astrophysics Data System (ADS)

    Smirnov, Artem; Dettrick, Sean; Clary, Ryan; Korepanov, Sergey; Thompson, Matthew; Trask, Erik; Tuszewski, Michel

    2012-10-01

    A high-confinement operating regime [1] with plasma lifetimes significantly exceeding past empirical scaling laws was recently obtained by combining plasma gun edge biasing and tangential Neutral Beam Injection (NBI) in the C-2 field-reversed configuration (FRC) experiment [2, 3]. We present experimental and computational results on the interaction of fast ions with the n=2 rotational and n=1 wobble modes in the C-2 FRC. It is found that the n=2 mode is similar to quadrupole magnetic fields in its detrimental effect on the fast ion transport due to symmetry breaking. The plasma gun generates an inward radial electric field, thus stabilizing the n=2 rotational instability without applying the quadrupole magnetic fields. The resultant FRCs are nearly axisymmetric, which enables fast ion confinement. The NBI further suppresses the n=2 mode, improves the plasma confinement characteristics, and increases the plasma configuration lifetime [4]. The n=1 wobble mode has relatively little effect on the fast ion transport, likely due to the approximate axisymmetry about the displaced plasma column. [4pt] [1] M. Tuszewski et al., Phys. Rev. Lett. 108, 255008 (2012).[0pt] [2] M. Binderbauer et al., Phys. Rev. Lett. 105, 045003 (2010).[0pt] [3] H.Y. Guo et al., Phys. Plasmas 18, 056110 (2011).[0pt] [4] M. Tuszewski et al., Phys. Plasmas 19, 056108 (2012)

  7. Preface: phys. stat. sol. (a) 202/12

    NASA Astrophysics Data System (ADS)

    Neumann, Wolfgang; Stutzmann, Martin; Hildebrandt, Stefan

    2005-09-01

    The present special issue contains a collection of Original Papers dedicated to Professor Johannes Heydenreich on the occasion of his 75th birthday.Johannes Heydenreich, born on 20 June 1930 in Plauen/Vogtland near Dresden, studied physics at the Pädagogische Hochschule Potsdam, where he obtained his first academic degree Dipl. Phys. in 1958. He received his doctoral degree at the Martin Luther University in Halle in 1961 and the Habilitation degree in 1969. Already during his studies in Potsdam, he showed an interest in electron microscopy due to the influence of his teacher and supervisor Prof. Picht, one of the pioneers in electron optics. His interests were strengthened when Johannes Heydenreich did the experimental work for his Diploma degree at the Institute for Experimental Physics of the University of Halle, where he met Prof. Heinz Bethge for the first time. This was the beginning of a fruitful and longstanding collaboration. In 1962 Johannes Heydenreich joined the team of the later Institute for Solid State Physics and Electron Microscopy of the Academy of Sciences of the GDR, in Halle, for which the basis was laid by Prof. Bethge in 1960.Heydenreich has been working as Assistant Director for many years and played a decisive role in introducing and organising the various techniques of electron microscopy in the institute.The research activities of Prof. Heydenreich covered a broad spectrum over the years. At the beginning of his career he made significant contributions in the field of electron mirror microscopy. After that, his main interests were focused on transmission electron microscopy, ranging from diffraction contrast analysis of crystal defects to high-resolution electron microscopy and image processing. His favourite field was studies of defect-induced phenomena in advanced materials. The so-called Bethge-Heydenreich, the book Electron Microscopy in Solid State Physics, published at first in a German edition in 1982 and later in a revised

  8. Comparative study for highly Al and Mg doped ZnO thin films elaborated by sol gel method for photovoltaic application

    NASA Astrophysics Data System (ADS)

    El Hallani, G.; Nasih, S.; Fazouan, N.; Liba, A.; Khuili, M.; Sajieddine, M.; Mabrouki, M.; Laanab, L.; Atmani, E. H.

    2017-04-01

    Transparent conducting oxides such as ZnO doped with Al or Mg are commonly used in solar cells, light emitting diodes, photodetectors, and ultraviolet laser diodes. In our work, we focus on a comparative study of the structural, optical, and electrical properties of ZnO films highly doped with Al (AZO) and Mg (MZO). These films are deposited on glass substrates by the sol-gel spin coating method. The doping concentrations for Al and Mg are fixed to 5%-30%. The XRD spectra indicate that all the samples are polycrystalline with hexagonal wurtzite structures, exhibiting a preferred orientation along the (002) plane. Low degradation in crystallinity was observed for MZO even at a Mg concentration of 30%. The MgO phase started to appear compared to Al-doped layers where smaller grains are formed inducing a deterioration in the films just after doping but no new phase appeared. This result is in agreement with other experimental results [J. K. Rath, Sol. Energy Mater. Sol. Cells 76, 431-487 (2003); Morris et al., J. Appl. Phys. 67, 1079-1087 (1990)]. By AFM analysis, the results indicate a significantly rough surface for MZO compared to AZO films. For equal Al and Mg dopant concentrations, we observe that the transmittance spectra of MZO thin films are wider than those of AZO, indicating a shift toward shorter wavelengths with an optical gap energy equal to 3.67 eV. The electrical measurements of AZO and MZO thin films were made using the I-V characteristic obtained by the four probe method. All the films present an ohmic behavior. The conductivity and the mobility of AZO films were found to be better than those of MZO.

  9. Dirac Magnons in Honeycomb Ferromagnets

    NASA Astrophysics Data System (ADS)

    Pershoguba, Sergey S.; Banerjee, Saikat; Lashley, J. C.; Park, Jihwey; Ågren, Hans; Aeppli, Gabriel; Balatsky, Alexander V.

    2018-01-01

    The discovery of the Dirac electron dispersion in graphene [A. H. Castro Neto, et al., The Electronic Properties of Graphene, Rev. Mod. Phys. 81, 109 (2009), 10.1103/RevModPhys.81.109] led to the question of the Dirac cone stability with respect to interactions. Coulomb interactions between electrons were shown to induce a logarithmic renormalization of the Dirac dispersion. With a rapid expansion of the list of compounds and quasiparticle bands with linear band touching [T. O. Wehling, et al., Dirac Materials, Adv. Phys. 63, 1 (2014), 10.1080/00018732.2014.927109], the concept of bosonic Dirac materials has emerged. We consider a specific case of ferromagnets consisting of van der Waals-bonded stacks of honeycomb layers, e.g., chromium trihalides CrX3 (X =F , Cl, Br and I), that display two spin wave modes with energy dispersion similar to that for the electrons in graphene. At the single-particle level, these materials resemble their fermionic counterparts. However, how different particle statistics and interactions affect the stability of Dirac cones has yet to be determined. To address the role of interacting Dirac magnons, we expand the theory of ferromagnets beyond the standard Dyson theory [F. J. Dyson, General Theory of Spin-Wave Interactions, Phys. Rev. 102, 1217 (1956), 10.1103/PhysRev.102.1217, F. J. Dyson, Thermodynamic Behavior of an Ideal Ferromagnet, Phys. Rev. 102, 1230 (1956), 10.1103/PhysRev.102.1230] to the case of non-Bravais honeycomb layers. We demonstrate that magnon-magnon interactions lead to a significant momentum-dependent renormalization of the bare band structure in addition to strongly momentum-dependent magnon lifetimes. We show that our theory qualitatively accounts for hitherto unexplained anomalies in nearly half-century-old magnetic neutron-scattering data for CrBr3 [W. B. Yelon and R. Silberglitt, Renormalization of Large-Wave-Vector Magnons in Ferromagnetic CrBr3 Studied by Inelastic Neutron Scattering: Spin-Wave Correlation

  10. Atom-chip-based quantum gravimetry for the precise determination of absolute gravity

    NASA Astrophysics Data System (ADS)

    Abend, Sven; Schubert, Christian; Ertmer, Wolfgang; Rasel, Ernst

    2017-04-01

    CRC 1128 geo-Q, the RTG 1729, the QUEST-LFS, by the German Space Agency (DLR) with funds provided by the Federal Ministry of Economic Affairs and Energy (BMWi) due to an enactment of the German Bundestag under Grant No. DLR 50WM1552-1557. [1] A. Peters et al., Nature 400, 849, 1999; A. Louchet-Chauvet et al., New J. Phys. 13, 065026, 2011; C. Freier et al., J. of Phys.: Conf. Series 723, 012050, 2016; V. Schkolnik et al., Appl. Phys. B 120, 311-316 (2015). [2] K. B. Davis et al., Phys. Rev. Lett. 74, 5202, 1995; M. H. Anderson et al., Science 269, 198, 1995; C. C. Bradley et al., Phys. Rev. Lett. 75, 1687, 1995. [3] S. Abend et al., Phys. Rev. Lett. 117, 203003, 2016. [4] J. Rudolph et al., New J. Phys. 17, 065001, 2015.

  11. Experimental noise-resistant Bell-inequality violations for polarization-entangled photons

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bovino, Fabio A.; Castagnoli, Giuseppe; Cabello, Adan

    2006-06-15

    We experimentally demonstrate that violations of Bell's inequalities for two-photon polarization-entangled states with colored noise are extremely robust, whereas this is not the case for states with white noise. Controlling the amount of noise by using the timing compensation scheme introduced by Kim et al. [Phys. Rev. A 67, 010301(R) (2003)], we have observed violations even for states with very high noise, in excellent agrement with the predictions of Cabello et al. [Phys. Rev. A 72, 052112 (2005)].

  12. Evidence for negative thermal expansion in the superconducting precursor phase SmFeAsO

    NASA Astrophysics Data System (ADS)

    Zhou, H. D.; Sarte, P. M.; Conner, B. S.; Balicas, L.; Wiebe, C. R.; Chen, X. H.; Wu, T.; Wu, G.; Liu, R. H.; Chen, H.; Fang, D. F.

    2018-03-01

    The fluorine-doped rare-earth iron oxypnictide series SmFeAsO1-x F x (0 ≤slant x ≤slant 0.10) was investigated with high resolution powder x-ray scattering. In agreement with previous studies (Margadonna et al 2009 Phys. Rev. B. 79 014503), the parent compound SmFeAsO exhibits a tetragonal-to-orthorhombic structural distortion at T{S}   =  130 K which is rapidly suppressed by x ≃ 0.10 deep within the superconducting dome. The change in unit cell symmetry is followed by a previously unreported magnetoelastic distortion at 120 K. The temperature dependence of the thermal expansion coefficient αV reveals a rich phase diagram for SmFeAsO: (i) a global minimum at 125 K corresponds to the opening of a spin-density wave instability as measured by pump-probe femtosecond spectroscopy (Mertelj et al 2010 Phys. Rev. B 81 224504) whilst (ii) a global maximum at 110 K corresponds to magnetic ordering of the Sm and Fe sublattices as measured by magnetic x-ray scattering (Nandi et al 2011 Phys. Rev. B 84 055419). At much lower temperatures than T{N} , SmFeAsO exhibits a significant negative thermal expansion on the order of  -40 ppm · K-1 in contrast to the behaviour of other rare-earth oxypnictides such as PrFeAsO (Kimber et al 2008 Phys. Rev. B 78 140503) and the actinide oxypnictide NpFeAsO (Klimczuk et al 2012 Phys. Rev. B 85 174506) where the onset of αV < 0 only appears in the vicinity of magnetic ordering. Correlating this feature with the temperature and doping dependence of the resistivity and the unit cell parameters, we interpret the negative thermal expansion as being indicative of the possible condensation of itinerant electrons accompanying the opening of a SDW gap, consistent with transport measurements (Tropeano et al 2009 Supercond. Sci. Technol. 22 034004).

  13. Helical flow in RFX-mod tokamak plasmas

    NASA Astrophysics Data System (ADS)

    Piron, L.; Zaniol, B.; Bonfiglio, D.; Carraro, L.; Kirk, A.; Marrelli, L.; Martin, R.; Piron, C.; Piovesan, P.; Zuin, M.

    2017-05-01

    This work presents the first evidence of helical flow in RFX-mod q(a)  <  2 tokamak plasmas. The flow pattern is characterized by the presence of convective cells with m  =  1 and n  =  1 periodicity in the poloidal and toroidal directions, respectively. A similar helical flow deformation has been observed in the same device when operated as a reversed field pinch (RFP). In RFP plasmas, the flow dynamic is tailored by the innermost resonant m  =  1, n  =  7 tearing mode, which sustains the magnetic field configuration through the dynamo mechanism (Bonomo et al 2011 Nucl. Fusion 51 123007). By contrast, in the tokamak experiments presented here, it is strongly correlated with the m  =  1, n  =  1 MHD activity. A helical deformation of the flow pattern, associated with the deformation of the magnetic flux surfaces, is predicted by several codes, such as Specyl (Bonfiglio et al 2005 Phys. Rev. Lett. 94 145001), PIXIE3D (Chacón et al 2008 Phys. Plasmas 15 056103), NIMROD (King et al 2012 Phys. Plasmas 19 055905) and M3D-C1 (Jardin et al 2015 Phys. Rev. Lett. 115 215001). Among them, the 3D fully non-linear PIXIE3D has been used to calculate synthetic flow measurements, using a 2D flow modelling code. Inputs to the code are the PIXIE3D flow maps, the ion emission profiles as calculated by a 1D collisional radiative impurity transport code (Carraro et al 2000 Plasma Phys. Control. Fusion 42 731) and a synthetic diagnostic with the same geometry installed in RFX-mod. Good agreement between the synthetic and the experimental flow behaviour has been obtained, confirming that the flow oscillations observed with the associated convective cells are a signature of helical flow.

  14. Theory of the inverse spin galvanic effect in quantum wells

    NASA Astrophysics Data System (ADS)

    Maleki Sheikhabadi, Amin; Miatka, Iryna; Sherman, E. Ya.; Raimondi, Roberto

    2018-06-01

    The understanding of the fundamentals of spin and charge densities and currents interconversion by spin-orbit coupling can enable efficient applications beyond the possibilities offered by conventional electronics. For this purpose we consider various forms of the frequency-dependent inverse spin galvanic effect in semiconductor quantum wells and epilayers taking into account the cubic in the electron momentum spin-orbit coupling in the Rashba and Dresselhaus forms, concentrating on the current-induced spin polarization (CISP). We find that including the cubic terms qualitatively explains recent findings of the CISP in InGaAs epilayers being the strongest if the internal spin-orbit coupling field is the smallest and vice versa [Norman et al., Phys. Rev. Lett. 112, 056601 (2014), 10.1103/PhysRevLett.112.056601; Luengo-Kovac et al., Phys. Rev. B 96, 195206 (2017), 10.1103/PhysRevB.96.195206], in contrast to the common understanding. Our results provide a promising framework for the control of spin transport in future spintronics devices.

  15. Precision theoretical analysis of neutron radiative beta decay to order O (α2/π2)

    NASA Astrophysics Data System (ADS)

    Ivanov, A. N.; Höllwieser, R.; Troitskaya, N. I.; Wellenzohn, M.; Berdnikov, Ya. A.

    2017-06-01

    In the Standard Model (SM) we calculate the decay rate of the neutron radiative β- decay to order O (α2/π2˜10-5), where α is the fine-structure constant, and radiative corrections to order O (α /π ˜10-3). The obtained results together with the recent analysis of the neutron radiative β- decay to next-to-leading order in the large proton-mass expansion, performed by Ivanov et al. [Phys. Rev. D 95, 033007 (2017), 10.1103/PhysRevD.95.033007], describe recent experimental data by the RDK II Collaboration [Bales et al., Phys. Rev. Lett. 116, 242501 (2016), 10.1103/PhysRevLett.116.242501] within 1.5 standard deviations. We argue a substantial influence of strong low-energy interactions of hadrons coupled to photons on the properties of the amplitude of the neutron radiative β- decay under gauge transformations of real and virtual photons.

  16. Light ion induced L X-ray production cross-sections in Au and Pb

    NASA Astrophysics Data System (ADS)

    Ouziane, S.; Amokrane, A.; Toumert, I.

    2008-04-01

    Experimental proton-induced Lα, Lβ, Lγ, Lℓ and Ltot absolute X-ray production cross-sections for Au and Pb in the incident proton energy range between 1 and 2.5 MeV are presented. The experimental results for X-ray production cross-sections are compared to available data given in Sokhi and Crumpton [R.S. Sokhi, D. Crumpton, At. Data Nucl. Data Tables 30 (1984) 49], Jesus et al. [A.P. Jesus, J.S. Lopes, J.P. Ribeiro, J. Phys. B: At. Mol. Phys. 18 (1985) 2456; A.P. Jesus, T.M. Pinheiro, I.A. Nisa, J.P. Ribeiro, J.S. Lopes, Nucl. Instrum. Methods B15 (1986) 95] and Goudarzi et al. [M. Goudarzi, F. Shokouhi, M. Lamehi-Rachti, P.Olialiy, Nucl. Instrum. Methods Phys. Res. B247 (2006) 218]. The given data are also compared with the predictions of ECPSSR model [W. Brandt, G. Lapicki, Phys. Rev. A23 (1981) 1717].

  17. Scanning Gate Microscopy on a Quantum Hall Interferometer

    NASA Astrophysics Data System (ADS)

    Martins, Frederico; Hackens, Benoit; Dutu, Augustin; Bayot, Vincent; Sellier, Hermann; Huant, Serge; Desplanque, Ludovic; Wallart, Xavier; Pala, Marco

    2010-03-01

    We perform scanning gate microscopy (SGM) experiments [1] at very low temperature (down to 100 mK) in the Quantum Hall regime on a mesoscopic quantum ring (QR) patterned in an InGaAs/InAlAs heterostructure. Close to integer filling factors ν=6, 8 and 10,the magnetoresistance of the QR is decorated with fast periodic oscillations, with a magnetic field period close to AB/ν, where AB is the Aharonov-Bohm period. We analyze the data in terms of electron tunneling between edge states trapped inside the QR and those transmitted through the QR openings [2]. SGM images reveal that the tip-induced perturbation of the electron confining potential gives rise to a rich pattern of narrow and wide concentric conductance fringes in the vicinity of the QR. [1] F. Martins et al. Phys. Rev. Lett. 99 136807 (2007); B. Hackens et al. Nat. Phys. 2 826 (2006). [2] B. Rosenow and B. I. Halperin, Phys. Rev. Lett. 98, 106801 (2007).

  18. Isolation of Coherent Synchrotron Emission During Relativistic Laser Plasma Interactions

    NASA Astrophysics Data System (ADS)

    Dromey, B.; Rykovanov, S. G.; Lewis, C. L. S.; Zepf, M.

    Coherent Synchrotron Emission (CSE) from relativistic laser plasmas (Pukhov et al., Plas Phys Control Fusion 52:124039, 2010; Dromey et al., Nat Phys 8:804-808, 2012; Dromey et al., New J Phys 15:015025, 2013) has recently been identified as a unique platform for the generation of coherent extreme ultraviolet (XUV) and X-Ray radiation with clear potential for bright attosecond pulse production. Exploiting this potential requires careful selection of interaction geometry, spectral wavelength range and target characteristics to allow the generation of high fidelity single attosecond pulses. In the laboratory the first step on this road is to study the individual mechanisms driving the emission of coherent extreme ultraviolet and X-Ray radiation during laser solid interactions in isolation. Here we show how interactions can be tailored to permit the unambiguous observation of coherent synchrotron emission (CSE) and the implications of this geometry for the resulting harmonic spectrum over the duration of the interaction.

  19. Nanobridge SQUIDs as calorimetric inductive particle detectors

    NASA Astrophysics Data System (ADS)

    Gallop, John; Cox, David; Hao, Ling

    2015-08-01

    Superconducting transition edge sensors (TESs) have made dramatic progress since their invention some 65 years ago (Andrews et al 1949 Phys. Rev. 76 154-155 Irwin and Hilton 2005 Topics Appl. Phys. 99 63-149) until now there are major imaging arrays of TESs with as many as 7588 separate sensors. These are extensively used by astronomers for some ground-breaking observations (Hattori et al 2013 Nucl. Instrum. Methods Phys. Res. A 732 299-302). The great success of TES systems has tended to overshadow other superconducting sensor developments. However there are other types (Sobolewski et al 2003 IEEE Trans. Appl. Supercond. 13 1151-7 Hadfield 2009 Nat. Photonics 3 696-705) which are discussed in papers within this special edition of the journal. Here we describe a quite different type of detector, also applicable to single photon detection but possessing possible advantages (higher sensitivity, higher operating temperature) over the conventional TES, at least for single detectors.

  20. Scaling of Guide-Field Magnetic Reconnection using Anisotropic Fluid Closure

    NASA Astrophysics Data System (ADS)

    Ohia, O.; Egedal, J.; Lukin, V. S.; Daughton, W.; Le, A.

    2012-10-01

    Collisionless magnetic reconnection, a process linked to solar flares, coronal mass ejections, and magnetic substorms, has been widely studied through fluid models and fully kinetic simulations. While fluid models often reproduce the fast reconnection rate of fully kinetic simulations, significant differences are observed in the structure of the reconnection regions [1]. However, guide-field fluid simulations implementing new equations of state that accurately account for the anisotropic electron pressure [2] reproduce the detailed reconnection region observed in kinetic simulations [3]. Implementing this two-fluid simulation using the HiFi framework [4], we study the force balance of the electron layers in guide-field reconnection and derive scaling laws for their characteristics.[1ex] [1] Daughton W et al., Phys. Plasmas 13, 072101 (2006).[0ex] [2] Le A et al., Phys. Rev. Lett. 102, 085001 (2009). [0ex] [3] Ohia O, et al., Phys. Rev. Lett. In Press (2012).[0ex] [4] Lukin VS, Linton MG, Nonlinear Proc. Geoph. 18, 871 (2011)

  1. Highly Regioregular Polythiophenes for Magneto-Optical Applications

    DTIC Science & Technology

    2010-07-01

    Macromolecules, 2007, 40, 8142-8150 Lieven De Cremer et.al., Macromolecules, 2008, 41, 568-578 Lieven De Cremer et.al., Macromolecules, 2008, 41, 591-598 Marnix...Vangheluwe et.al., Macromolecules, 2008, 41, 1041-1044 David Cornelis et.al., Chem. Mater. 2008, 20, 2133-2143 Palash Gangopadhyay et.al., J. Phys

  2. Response to Kruse-Plass et al. (2017) regarding the risk to non-target lepidopteran larvae exposed to pollen from one or more of three Bt maize events (MON810, Bt11 and 1507).

    PubMed

    Perry, Joe N; Barberi, Paolo; Bartsch, Detlef; Birch, A N E; Gathmann, Achim; Kiss, Jozsef; Manachini, Barbara; Nuti, Marco; Rauschen, Stefan; Schiemann, Joachim; Schuppener, Mechthild; Sweet, Jeremy; Tebbe, Christoph C; Veronesi, Fabio

    2017-01-01

    We respond to the paper of Kruse-Plass et al. (Environ Sci Eur 29:12, 2017), published in this journal, regarding the risk to non-target lepidopteran larvae exposed to pollen from one or more of three Bt maize events (MON810, Bt11 and 1507). We emphasise that what is important for environmental risk assessment is not the number of pollen grains per se, but the degree of exposure of a NT lepidopteran larva to Bt protein contained in maize pollen. The main text of this response deals with general issues which Kruse-Plass et al. have failed to understand; more detailed refutations of each of their claims are given in Additional file 1. Valid environmental risk assessment requires direct measurement of pollen on leaves at varying distances outside a source field(s); such measurements reflect the potential exposure experienced by an individual larva on a host plant. There are no new data in the Kruse-Plass et al. paper, or indeed any data directly quantifying pollen on actual host-plant leaves outside a maize field; only data gathered within or at the edge of maize crops were reported. Values quoted by Kruse-Plass et al. for deposition on host plants outside the field were estimates only. We reiterate the severe methodological criticisms made by EFSA [Relevance of a new scientific publication (Hofmann et al. 2016) for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of Bt-maize events MON810, Bt11 and 1507. EFSA Supp Publ; EN-1070, 2016], which render this estimation procedure unreliable. Furthermore, criticisms of EFSA (EFSA J 2015(13):4127, 2015) and of EFSA [Relevance of a new scientific publication (Hofmann et al. 2016) for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of Bt-maize events MON810, Bt11 and 1507. EFSA Supp Publ; EN-1070, 2016] made by Kruse-Plass et al. are shown in Additional file 1 to be without foundation. We therefore consider that

  3. Pseudogap in normal underdoped phase of Bi2212: LDA + DMFT + Σk

    NASA Astrophysics Data System (ADS)

    Nekrasov, I. A.; Kuchinskii, E. Z.; Pchelkina, Z. V.; Sadovskii, M. V.

    2007-09-01

    Pseudogap phenomena are observed for normal underdoped phase of different high- Tc cuprates. Among others Bi 2Sr 2CaCu 2O 8- δ (Bi2212) compound is one of the most studied experimentally [A. Damascelli, Z. Hussain, Z.-X. Shen, Rev. Mod. Phys. 75 (2003) 473; J.C. Campuzano, M.R. Norman, M. Randeria, in: K.H. Bennemann, J.B. Ketterson (Eds.), Physics of Superconductors, vol. 2, Springer, Berlin, 2004, p. 167; J. Fink et al., cond-mat/0512307; X.J. Zhou et al., cond-mat/0604284]. To describe pseudogap regime in Bi2212, we employ novel generalized DMFT + Σk approach [E.Z. Kuchinskii, I.A. Nekrasov, M.V. Sadovskii, JETP Lett. 82 (2005) 198; M.V. Sadovskii et al., Phys. Rev. B 72 (2005) 155105, and these proceedings, doi:10.1016/j.physc.2007.03.367]. This approach gives possibility to preserve conventional dynamical mean-field theory (DMFT) equations [A. Georges et al., Rev. Mod. Phys. 68 (1996) 13] and include an additional (momentum dependent) self-energy Σk. In the present case, Σk describes non-local dynamical correlations induced by short-ranged collective Heisenberg-like antiferromagnetic spin fluctuations [M.V. Sadovskii, Physics-Uspekhi 44 (2001) 515, cond-mat/0408489]. The effective single impurity problem in the DMFT + Σk is solved by numerical renormalization group (NRG) [R. Bulla, A.C. Hewson, Th. Pruschke, J. Phys. Cond. Mat. 10 (1998) 8365; R. Bulla, Phys. Rev. Lett. 83 (1999) 136]. To take into account material specific properties of two neighboring CuO 2 layers of Bi2212 we employ local density approximation (LDA) to calculate necessary model parameters, e.g. the values of intra- and interlayer hopping integrals between Cu-sites. Onsite Coulomb interaction U for x2- y2 orbital was calculated in constrained LDA method [O. Gunnarsson et al., Phys. Rev. B 39 (1989) 1708]. The value of pseudogap potential Δ was obtained within DMFT(NRG) [E.Z. Kuchinskii, I.A. Nekrasov, M.V. Sadovskii, JETP Lett. 82 (2005) 198; M.V. Sadovskii et al., Phys. Rev. B 72

  4. Differential diagnostic perspectives provided by en face microscopic examination of articular surface defects.

    PubMed

    Rothschild, Bruce M

    2018-03-01

    Surface defects have a central position in diagnosis of articular pathology. Recognizing the limitations of standard radiologic techniques and those imposed by positioning and averaging artifacts on CT evaluation, direct visualization of surface defects was pursued to identify disease characteristics that would facilitate interpretation of radiologic findings. Epi-illumination surface microscopy was utilized to examine macroscopically recognized articular surface defects in individuals in the Hamann-Todd, Terry, and Huntington human skeletal collections with previously verified diagnoses of rheumatoid arthritis, spondyloarthropathy, juvenile inflammatory arthritis (JIA), calcium pyrophosphate deposition disease (CPPD), gout, metastatic cancer, multiple myeloma, septic arthritis, tuberculosis, fungal arthritis, histiocytosis and sickle cell anemia (Rothschild and Rothschild Clin Infect Dis 20(5):1402-1408, 1995; Rothschild et al. Amer J Phys Anthropol 82(4):441-449, 1990; Rothschild and Rothschild Amer J Phys Anthropol 96(4):357-563, 1995; Rothschild and Woods Clin Exp Rheumatol 10(2):117-122, 1992; Barrett and Keat Radiographics 24(6):1679-1691, 2004; Rothschild and Heathcote Amer J Phys Anthropol 98(4):519-525, 1995; Rothschild and Woods Am J Phys Anthropol 85:25-34, 1991; Hershkovitz et al. Amer J Phys Anthropol 106(1):47-60, 1998; Winland et al. Amer J Phys Anthropol 24:S243, 1997; Rothschild et al. Clin Exp Rheumatol 10(6):557-564, 1992; Rothschild and Martin , 2006; Rothschild et al. Amer J Phys Anthropol 102(2):249-264, 1997). Observed alterations were compared with standard radiographs. Fronts of resorption distinguished inflammatory arthritis from those caused by the other disorders studied. Multiple myeloma, fungal disease, and gout are expansile character; the latter accompanied by reactive new bone formation more prominent than that noted with spondyloarthropathy and JIA. Those were clearly distinguished from the crumbling alterations found with CPPD

  5. Cascade Model of Ionization Multiplication of Electrons in Glow Discharge Plasma

    NASA Astrophysics Data System (ADS)

    Romanenko, V. A.; Solodky, S. A.; Kudryavtsev, A. A.; Suleymanov, I. A.

    1996-10-01

    For determination of EDF in non-uniform fields a Monte-Carlo simulation(Tran Ngoc An et al., J.Phys.D: Appl. Phys. 10, 2317 (1977))^,(J.P. Boeuf et al., Phys.D: Appl.Phys. 15, 2169 (1982)) is applied. As alternative multi-beam cascade model(H.B. Valentini, Contrib.Plasma Phys. 27, 331 (1987)) is offered. Our model eliminates defects of that model and enables to determine EDF of low pressure plasma in non-uniform fields. A cascade model (with EDF dividing in monoenergetic electron groups) for arbitrary electric potential profile was used. Modeling was carried out for electron forward scattering only, constant electron mean free path; ionization was considered only. The equation system was solved for the region with kinetic energies more than ionization energy. The boundary conditions (on ionization energy curve) take into account electron transitions from higher-lying level in the less than ionization energy region and secondary electron production. The problem solution in analytical functions was obtained. The insertion of additional processes does not make significant difficulties. EDF and electrokinetical parameters in helium from numerical calculations are well agreed with above-mentioned authors. Work was carried out under RFFI (project N 96-02-18417) support.

  6. Universal formulation of excitonic linear absorption spectra in all semiconductor microstructures

    NASA Astrophysics Data System (ADS)

    Lefebvre, Pierre; Christol, Philippe; Mathieu, Henry

    1995-01-01

    We present a generalization of the well-known exciton absorption calculations of Elliott [Phys. Rev. 108, 1384 (1957)], in the 3-dimensional case, and of Shinada and Sugano [J. Phys. Soc. Japan 21, 1936 (1966)], for 2-dimensional media: We calculate the optical absorption spectra of bound and unbound exciton states, by using a metric space with a noninteger dimension α (1 < α), obtaining almost exactly the same theoretical lineshapes as those resulting from accurate but costly numerical approaches [Chuang et al. Phys. Rev. B, 43, 1500 (1991); Benner and Haug, Phys. Rev. B 47, 15750 (1993)].

  7. Progress Towards a High-Precision Infrared Spectroscopic Survey of the H_3^+ Ion

    NASA Astrophysics Data System (ADS)

    Perry, Adam J.; Hodges, James N.; Markus, Charles R.; Kocheril, G. Stephen; Jenkins, Paul A., II; McCall, Benjamin J.

    2015-06-01

    The trihydrogen cation, H_3^+, represents one of the most important and fundamental molecular systems. Having only two electrons and three nuclei, H_3^+ is the simplest polyatomic system and is a key testing ground for the development of new techniques for calculating potential energy surfaces and predicting molecular spectra. Corrections that go beyond the Born-Oppenheimer approximation, including adiabatic, non-adiabatic, relativistic, and quantum electrodynamic corrections are becoming more feasible to calculate. As a result, experimental measurements performed on the H_3^+ ion serve as important benchmarks which are used to test the predictive power of new computational methods. By measuring many infrared transitions with precision at the sub-MHz level it is possible to construct a list of the most highly precise experimental rovibrational energy levels for this molecule. Until recently, only a select handful of infrared transitions of this molecule have been measured with high precision (˜ 1 MHz). Using the technique of Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy, we are aiming to produce the largest high-precision spectroscopic dataset for this molecule to date. Presented here are the current results from our survey along with a discussion of the combination differences analysis used to extract the experimentally determined rovibrational energy levels. O. Polyansky, et al., Phil. Trans. R. Soc. A (2012), 370, 5014. M. Pavanello, et al., J. Chem. Phys. (2012), 136, 184303. L. Diniz, et al., Phys. Rev. A (2013), 88, 032506. L. Lodi, et al., Phys. Rev. A (2014), 89, 032505. J. Hodges, et al., J. Chem. Phys (2013), 139, 164201.

  8. Effects of polarization direction on laser-assisted free-free scattering

    NASA Astrophysics Data System (ADS)

    deHarak, B. A.; Kim, B. N.; Weaver, C. M.; Martin, N. L. S.; Siavashpouri, Mahsa; Nosarzewski, Benjamin

    2016-06-01

    This work will detail the effects of laser polarization direction (relative to the momentum transfer direction) on laser-assisted free-free scattering. Such processes play a role in the gas breakdown that occurs in electric discharges as well as providing a method for the laser heating of a plasma (Musa et al 2010 J. Phys. B: At. Mol. Opt. Phys. 43 175201, Mason 1993 Rep. Prog. Phys. 56 1275). Experimental results will be presented for electron-helium scattering in the presence of an Nd:YAG laser field (hν =1.17 eV) where the polarization direction was varied in a plane that is perpendicular to the scattering plane. To date, all of our experimental results are well described by the Kroll-Watson approximation (KWA) (Kroll and Watson 1973 Phys. Rev. A 8 804). The good agreement between our experiments and calculations using the KWA includes the case where the polarization is perpendicular to the momentum transfer direction, for which the KWA predicts vanishing cross section; other workers have found that the KWA tends to be inaccurate for cases where it predicts small cross sections (e.g. Musa et al 2010 J. Phys. B: At. Mol. Opt. Phys. 43 175201). We also present simulations of the effects that multiple scattering might have on experimental measurements. In particular, we examine conditions that are expected to be similar to those of the experiments reported by Wallbank and Holmes (Wallbank and Holmes 1993 Phys. Rev. A 48 R2515).

  9. Does atomic polarizability play a role in hydrogen radio recombination spectra from Galactic H II regions?

    NASA Astrophysics Data System (ADS)

    Hey, J. D.

    2013-09-01

    Since highly excited atoms, which contribute to the radio recombination spectra from Galactic H II regions, possess large polarizabilities, their lifetimes are influenced by ion (proton)-induced dipole collisions. It is shown that, while these ion-radiator collisional processes, if acting alone, would effectively limit the upper principal quantum number attainable for given plasma parameters, their influence is small relative to that of electron impacts within the framework of line broadening theory. The present work suggests that ion-permanent dipole interactions (Hey et al 2004 J. Phys. B: At. Mol. Opt. Phys. 37 2543) would also be of minor importance in limiting the occupation of highly excited states. On the other hand, the ion-induced dipole collisions are essential for ensuring equipartition of energy between atomic and electron kinetic distributions (Hey et al 1999 J. Phys. B: At. Mol. Opt. Phys. 32 3555; 2005 J. Phys. B: At. Mol. Opt. Phys. 38 3517), without which Voigt profile analysis to extract impact broadening widths would not be possible. Electron densities deduced from electron impact broadening of individual lines (Griem 1967 Astrophys. J. 148 547; Watson 2006 J. Phys. B: At. Mol. Opt. Phys. 39 1889) may be used to check the significance of the constraints arising from the present analysis. The spectra of Bell et al (2000 Publ. Astron. Soc. Pac. 112 1236; 2011 Astrophys. Space Sci. 333 377; 2011 Astrophys. Space Sci. 335 451) for Orion A and W51 in the vicinity of 6.0 and 17.6 GHz are examined in this context, and also in terms of a possible role of the background ion microfield in reducing the near-elastic contributions to the electron impact broadening below the predictions of theory (Hey 2012 J. Phys. B: At. Mol. Opt. Phys. 45 065701). These spectra are analysed, subject to the constraint that calculated relative intensities of lines, arising from upper states in collisional-radiative equilibrium, should be consistent with those obtained from

  10. Induction of Interleukin-6 During Human Immunodeficiency Virus Infection

    DTIC Science & Technology

    1990-12-01

    possibility is supported by the observation proportion of patients with rheumatoid arthritis .2 ’ In this that individuals infected with HIV capable of...synovial effusions of patients with rheumatoid 2310 BIRX ET AL arthritis and other arthritides: Identification of several isoforms and Chermann J-C...mononuclear phagocytes in HTLV-III/ rheumatoid arthritis . Eur J Immunol 18:1797, 1988 LAV infection. Science 233:215, 1986 24. Houssiau FA, Devogelaer

  11. Genetic Radiotherapy of Prostate Cancer

    DTIC Science & Technology

    2004-12-01

    notherapy to increase efficacy and apoptosis in breast cancer receptor subtype specificity and in vivo binding of a novel xenografts . Cancer Res 62:4263...et al: Enhanced peutic use. Eur J Nucl Med 27:273-282, 2000 in vivo gene delivery to human ovarian cancer xenografts 75. Schally AV: Oncological...inherently less sensitive to 5-FU-mediated radiosensitization than human colon xenografts based solely upon their relatively slow growth in vivo

  12. Electronic Structure in Thin Film Organic Semiconductors

    DTIC Science & Technology

    2009-06-27

    Peltekis, C. McGuinness, and A. Matsuura, J. Chem. Phys. 129, 224705, (2008) c) "The Local Electronic Structure of Tin Phthalocyanine studied by...interfaces in a Cu(100)-benzenethiolate- pentacene heterostructure", Phys. Rev. Lett. 100, 027601 (2008). 21. O.V. Molodtsova, M. Grobosch, M. Knupfer...1999). 37. N.J. Watkins, S. Zorba, and Y. Gao, "Interface formation of pentacene on Al2O3", J. Appl. Phys. 96, 425 (2004). 38. K.V. Chauhan, I

  13. Magnetism of Al-substituted magnetite reduced from Al-hematite

    NASA Astrophysics Data System (ADS)

    Jiang, Zhaoxia; Liu, Qingsong; Zhao, Xiang; Roberts, Andrew P.; Heslop, David; Barrón, Vidal; Torrent, José

    2016-06-01

    Aluminum-substituted magnetite (Al-magnetite) reduced from Al-substituted hematite or goethite (Al-hematite or Al-goethite) is an environmentally important constituent of magnetically enhanced soils. In order to characterize the magnetic properties of Al-magnetite, two series of Al-magnetite samples were synthesized through reduction of Al-hematite by a mixed gas (80% CO2 and 20% CO) at 395°C for 72 h in a quartz tube furnace. Al-magnetite samples inherited the morphology of their parent Al-hematite samples, but only those transformed from Al-hematite synthesized at low temperature possessed surficial micropores, which originated from the release of structural water during heating. Surface micropores could thus serve as a practical fingerprint of fire or other high-temperature mineralogical alteration processes in natural environments, e.g., shear friction in seismic zones. In addition, Al substitution greatly affects the magnetic properties of Al-magnetite. For example, coercivity (Bc) increases with increasing Al content and then decreases slightly, while the saturation magnetization (Ms), Curie temperature (Tc), and Verwey transition temperature (Tv) all decrease with increasing Al content due to crystal defect formation and dilution of magnetic ions caused by Al incorporation. Moreover, different trends in the correlation between Tc and Bc can be used to discriminate titanomagnetite from Al-magnetite, which is likely to be important in environmental and paleomagnetic studies, particularly in soil.

  14. Superconducting Resonators with Parasitic Electromagnetic Environments

    NASA Astrophysics Data System (ADS)

    Hornibrook, John; Mitchell, Emma; Reilly, David

    2012-02-01

    Microwave losses in niobium superconducting resonators are investigated at milli-Kelvin temperatures and with low drive power. In addition to the well-known suppression of Q-factor that arises from coupling between the resonator and two-level defects in the dielectric substrate [1-4], we report strong dependence of the loaded Q-factor and resonance line-shape on the electromagnetic environment. Methods to suppress parasitic coupling between the resonator and its environment are demonstrated.[4pt] [1] Day, P.K. et al., Nature 425, 817-821 (2003).[0pt] [2] Wallraff, A. et. al., Nature 451, 162-167 (2004).[0pt] [3] Macha, P. et. al., Appl. Phys. Lett., 96, 062503 (2010).[0pt] [4] O'Connell, A.D. et. al., Appl. Phys. Lett., 92, 112903 (2008).

  15. 1 D analysis of Radiative Shock damping by lateral radiative losses

    NASA Astrophysics Data System (ADS)

    Busquet, Michel; Audit, Edouard

    2008-11-01

    We have demonstrated the effect of the lateral radiative losses in radiative shocks propagative in layered quasi-planar atmospheres.[1,2] The damping of the precursor is sensitive to the fraction of self-emitted radiation reflected by the walls (called albedo) We have given recently an experimental determination of the wall albedo.[2] For parametric analysis of this effect, we implement lateral losses in the 1D hydro-rad code MULTI [3] and compared results with 2D simulations. [1] S.Leygnac, et al., Phys. Plasmas 13, 113301 (2006) [2] M.Busquet, et al, High Energy Density Plasmas 3, 8-11 (2007); M.Gonzalez, et al, Laser Part. Beams 24, 1-6 (2006) [3] Ramis et al, Comp. Phys. Comm., 49, 475 (1988)

  16. Kinetic theory of turbulence for parallel propagation revisited: Formal results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yoon, Peter H., E-mail: yoonp@umd.edu

    2015-08-15

    In a recent paper, Gaelzer et al. [Phys. Plasmas 22, 032310 (2015)] revisited the second-order nonlinear kinetic theory for turbulence propagating in directions parallel/anti-parallel to the ambient magnetic field. The original work was according to Yoon and Fang [Phys. Plasmas 15, 122312 (2008)], but Gaelzer et al. noted that the terms pertaining to discrete-particle effects in Yoon and Fang's theory did not enjoy proper dimensionality. The purpose of Gaelzer et al. was to restore the dimensional consistency associated with such terms. However, Gaelzer et al. was concerned only with linear wave-particle interaction terms. The present paper completes the analysis bymore » considering the dimensional correction to nonlinear wave-particle interaction terms in the wave kinetic equation.« less

  17. A Systematic Evaluation of the Extent of Photochemical Processing in Different Types of Secondary Organic Aerosols in the Aqueous Phase

    NASA Astrophysics Data System (ADS)

    Romonosky, D.; Lee, H.; Epstein, S. A.; Nizkorodov, S.; Laskin, J.; Laskin, A.

    2013-12-01

    al. Photolytic processing of secondary organic aerosols dissolved in cloud droplets. Phys. Chem. Chem. Phys. 2011, 13, 12199. Nguyen et al. Direct aqueous photochemistry of isoprene high-NOx secondary organic aerosol. Phys. Chem. Chem. Phys. 2012, 14, 9702. Walser et al. Photochemical aging of secondary organic aerosol particles generated from the oxidation of d-limonene. J. Phys. Chem. A 2007, 111, 1907.

  18. Familial ALS

    PubMed Central

    Boylan, Kevin

    2015-01-01

    Synopsis Genes linked to ALS susceptibility are being identified at an increasing rate owing to advances in molecular genetic technology. Genetic mechanisms in ALS pathogenesis appear to exert major effects in ~10% of patients, but genetic factors at some level may be important components of disease risk in most ALS patients. Identification of gene variants associated with ALS has informed concepts of the pathogenesis of ALS, aided the identification of therapeutic targets, facilitated research to develop new ALS biomarkers, and supported the establishment of clinical diagnostic tests for ALS-linked genes. Translation of this knowledge to ALS therapy development is ongoing. PMID:26515623

  19. Ab initio modeling of zincblende AlN layer in Al-AlN-TiN multilayers

    DOE PAGES

    Yadav, S. K.; Wang, J.; Liu, X. -Y.

    2016-06-13

    An unusual growth mechanism of metastable zincblende AlN thin film by diffusion of nitrogen atoms into Al lattice is established. Using first-principles density functional theory, we studied the possibility of thermodynamic stability of AlN as a zincblende phase due to epitaxial strains and interface effect, which fails to explain the formation of zincblende AlN. We then compared the formation energetics of rocksalt and zincblende AlN in fcc Al through direct diffusion of nitrogen atoms to Al octahedral and tetrahedral interstitials. Furthermore, the formation of a zincblende AlN thin film is determined to be a kinetically driven process, not a thermodynamicallymore » driven process.« less

  20. Interfacial characterization of Al-Al thermocompression bonds

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Malik, N., E-mail: nishantmalik1987@gmail.com; SINTEF ICT, Department of Microsystems and Nanotechnology, P.O. Box 124 Blindern, N-0314 Oslo; Carvalho, P. A.

    2016-05-28

    Interfaces formed by Al-Al thermocompression bonding were studied by the transmission electron microscopy. Si wafer pairs having patterned bonding frames were bonded using Al films deposited on Si or SiO{sub 2} as intermediate bonding media. A bond force of 36 or 60 kN at bonding temperatures ranging from 400–550 °C was applied for a duration of 60 min. Differences in the bonded interfaces of 200 μm wide sealing frames were investigated. It was observed that the interface had voids for bonding with 36 kN at 400 °C for Al deposited both on Si and on SiO{sub 2}. However, the dicing yield was 33% for Al onmore » Si and 98% for Al on SiO{sub 2}, attesting for the higher quality of the latter bonds. Both a bond force of 60 kN applied at 400 °C and a bond force of 36 kN applied at 550 °C resulted in completely bonded frames with dicing yields of, respectively, 100% and 96%. A high density of long dislocations in the Al grains was observed for the 60 kN case, while the higher temperature resulted in grain boundary rotation away from the original Al-Al interface towards more stable configurations. Possible bonding mechanisms and reasons for the large difference in bonding quality of the Al films deposited on Si or SiO{sub 2} are discussed.« less

  1. Correction: Towards the rationalization of catalytic activity values by means of local hyper-softness on the catalytic site: a criticism about the use of net electric charges.

    PubMed

    Martínez-Araya, Jorge Ignacio; Grand, André; Glossman-Mitnik, Daniel

    2016-01-28

    Correction for 'Towards the rationalization of catalytic activity values by means of local hyper-softness on the catalytic site: a criticism about the use of net electric charges' by Jorge Ignacio Martínez-Araya et al., Phys. Chem. Chem. Phys., 2015, DOI: 10.1039/c5cp03822g.

  2. Progress towards a loophole-free test of nonlocality

    NASA Astrophysics Data System (ADS)

    McCusker, Kevin; Christensen, Bradley; Kwiat, Paul; Altepeter, Joseph

    2012-02-01

    We report on our progress towards a loophole-free test of nonlocality using spontaneous parametric down-conversion (SPDC). While the timing loophole can be easily closed in such a system by moving the detectors far apart [1], closing the detector loophole is significantly more difficult. In the standard Bell entangled states with the maximal violation of the CHSH inequality [2], an overall efficiency of 83% is required. This limit can be lowered to 67% by using non-maximally entangled states (although sensitivity to noise is greatly increased) [3]. We are carefully engineering our source to achieve maximal heralding efficiency, by optimizing both the spatial and spectral filtering, while keeping noise low using high-extinction-ratio polarizing beamsplitters. Combined with high-efficiency detectors, either optimized visible-light photon counters [4] or transition-edge sensors [5], closure of the detection loophole is within reach. [4pt] [1] G. Weihs et al., Phys. Rev. Lett. 81, 5039 (1998).[2] J. F. Clauser et al., Phys. Rev. Lett. 23, 880 (1969).[3] P.H. Eberhard, Phys. Rev. A 47, R747 (1993).[4] S. Takeuchi et al., Appl. Phys. Lett. 74, 1063 (1999).[5] A. E. Lita, A. J. Miller, and S. Nam, Opt. Exp. 16, 3032 (2008).

  3. Atom chip gravimeter

    NASA Astrophysics Data System (ADS)

    Schubert, Christian; Abend, Sven; Gebbe, Martina; Gersemann, Matthias; Ahlers, Holger; Müntinga, Hauke; Matthias, Jonas; Sahelgozin, Maral; Herr, Waldemar; Lämmerzahl, Claus; Ertmer, Wolfgang; Rasel, Ernst

    2016-04-01

    1552-1557 (QUANTUS-IV-Fallturm) and by the Deutsche Forschungsgemeinschaft in the framework of the SFB 1128 geo-Q. [1] P. Berg et al., Composite-Light-Pulse Technique for High-Precision Atom Interferometry, Phys. Rev. Lett., 114, 063002, 2015. [2] A. Peters et al., Measurement of gravitational acceleration by dropping atoms, Nature 400, 849, 1999. [3] D. Schlippert et al., Quantum Test of the Universality of Free Fall, Phys. Rev. Lett., 112, 203002, 2014. [4] A. Louchet-Chauvet et al., The influence of transverse motion within an atomic gravimeter, New J. Phys. 13, 065026, 2011. [5] Q. Bodart et al., A cold atom pyramidal gravimeter with a single laser beam, Appl. Phys. Lett. 96, 134101, 2010. [6] H. Müntinga et al., Interferometry with Bose-Einstein Condensates in Microgravity, Phys. Rev. Lett., 110, 093602, 2013. [7] T. Kovachy et al., Matter Wave Lensing to Picokelvin Temperatures, Phys. Rev. Lett. 114, 143004, 2015. [8] J. Rudolph et al., A high-flux BEC source for mobile atom interferometers, New J. Phys. 17, 065001, 2015.

  4. Systematic study of the isotopic dependence of fusion dynamics for neutron- and proton-rich nuclei using a proximity formalism

    NASA Astrophysics Data System (ADS)

    Ghodsi, O. N.; Gharaei, R.; Lari, F.

    2012-08-01

    The behaviors of barrier characteristics and fusion cross sections are analyzed by changing neutrons over a wide range of colliding systems. For this purpose, we have extended our previous study [Ghodsi and Gharaei, Eur. Phys. J. AEPJAFV1434-600110.1140/epja/i2012-12021-x 48, 21 (2012), it is devoted to the colliding systems with neutron-rich nuclei] to 125 isotopic systems with the condition of 0.5⩽N/Z⩽1.6 for their compound nuclei. The AW 95, Bass 80, Denisov DP, and Prox. 2010 potentials are used to calculate the nuclear part of the interacting potential. The obtained results show that the trend of barrier heights VB and positions RB as well as nuclear VN and Coulomb VC potentials (at R=RB) as a function of (N/Z-1) quantity are nonlinear (second order) whereas the fusion cross sections follow a linear dependence.

  5. Segmental front line dynamics of randomly pinned ferroelastic domain walls

    NASA Astrophysics Data System (ADS)

    Puchberger, S.; Soprunyuk, V.; Schranz, W.; Carpenter, M. A.

    2018-01-01

    Dynamic mechanical analysis (DMA) measurements as a function of temperature, frequency, and dynamic force amplitude are used to perform a detailed study of the domain wall motion in LaAlO3. In previous DMA measurements Harrison et al. [Phys. Rev. B 69, 144101 (2004), 10.1103/PhysRevB.69.144101] found evidence for dynamic phase transitions of ferroelastic domain walls in LaAlO3. In the present work we focus on the creep-to-relaxation region of domain wall motion using two complementary methods. We determine, in addition to dynamic susceptibility data, waiting time distributions of strain jerks during slowly increasing stress. These strain jerks, which result from self-similar avalanches close to the depinning threshold, follow a power-law behavior with an energy exponent ɛ =1.7 ±0.1 . Also, the distribution of waiting times between events follows a power law N (tw) ∝tw-(n +1 ) with an exponent n =0.9 , which transforms to a power law of susceptibility S (ω ) ∝ω-n . The present dynamic susceptibility data can be well fitted with a power law, with the same exponent (n =0.9 ) up to a characteristic frequency ω ≈ω* , where a crossover from stochastic DW motion to the pinned regime is well described using the scaling function of Fedorenko et al. [Phys. Rev. B 70, 224104 (2004), 10.1103/PhysRevB.70.224104].

  6. Improved Analysis of GW150914 Using a Fully Spin-Precessing Waveform Model

    NASA Technical Reports Server (NTRS)

    Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Camp, J. B.; hide

    2016-01-01

    This paper presents updated estimates of source parameters for GW150914, a binary black-hole coalescence event detected by the Laser Interferometer Gravitational-wave Observatory (LIGO) in 2015 [Abbott et al. Phys. Rev. Lett. 116, 061102 (2016).]. Abbott et al. [Phys. Rev. Lett. 116, 241102 (2016).] presented parameter estimation of the source using a 13-dimensional, phenomenological precessing-spin model (precessing IMRPhenom) and an 11-dimensional nonprecessing effective-one-body (EOB) model calibrated to numerical-relativity simulations, which forces spin alignment (nonprecessing EOBNR). Here, we present new results that include a 15-dimensional precessing-spin waveform model (precessing EOBNR) developed within the EOB formalism. We find good agreement with the parameters estimated previously [Abbott et al. Phys. Rev. Lett. 116, 241102 (2016).], and we quote updated component masses of 35(+5)(-3) solar M; and 30(+3)(-4) solar M; (where errors correspond to 90 symmetric credible intervals). We also present slightly tighter constraints on the dimensionless spin magnitudes of the two black holes, with a primary spin estimate is less than 0.65 and a secondary spin estimate is less than 0.75 at 90% probability. Abbott et al. [Phys. Rev. Lett. 116, 241102 (2016).] estimated the systematic parameter-extraction errors due to waveform-model uncertainty by combining the posterior probability densities of precessing IMRPhenom and nonprecessing EOBNR. Here, we find that the two precessing-spin models are in closer agreement, suggesting that these systematic errors are smaller than previously quoted.

  7. Elucidating the Complex Lineshapes Resulting from the Highly Sensitive, Ion Selective, Technique Nice-Ohvms

    NASA Astrophysics Data System (ADS)

    Hodges, James N.; Siller, Brian; McCall, Benjamin J.

    2015-06-01

    The technique Noise Immune Cavity Enhanced Optical Heterodyne Velocity Modulation Spectroscopy, or NICE-OHVMS, has been used to great effect to precisely and accurately measure a variety of molecular ion transitions from species such as H_3^+, CH_5^+, HeH^+, and HCO^+, achieving MHz or in some cases sub-MHz uncertainty. It is a powerful technique, but a complete theoretical understanding of the complex NICE-OHVMS lineshape is needed to fully unlock its potential. NICE-OHVMS is the direct result of the combination of the highly sensitive spectroscopic technique Noise Immune Cavity Enhanced Optical Heterodyne Molecular Spectroscopy(NICE-OHMS) with Velocity Modulation Spectroscopy(VMS), applying the most sensitive optical detection method with ion species selectivity. The theoretical underpinnings of NICE-OHMS lineshapes are well established, as are those of VMS. This presentation is the logical extension of those two preceding bodies of work. Simulations of NICE-OHVMS lineshapes under a variety of conditions and fits of experimental data to the model are presented. The significance and accuracy of the various inferred parameters, along with the prospect of using them to extract additional information from observed transitions, are discussed. J.~N. Hodges, et al. J. Chem. Phys. (2013), 139, 164201. A.~J. Perry, et al. J. Chem. Phys. (2014), 141, 101101. K.~N. Crabtree, et al. Chem. Phys. Lett. (2012), 551, 1-6. F.~M. Schmidt, et al. J. Opt. Soc. Amer. A (2008), 24, 1392--1405. J.~W. Farley, J. Chem. Phys. (1991), 95, 5590--5602.

  8. Linear and nonlinear regimes of the 2-D Kelvin-Helmholtz/Tearing instability in Hall MHD.

    NASA Astrophysics Data System (ADS)

    Chacon, L.; Knoll, D. A.; Finn, J. M.

    2002-11-01

    The study to date of the magnetic field effects on the Kelvin-Helmholtz instability (KHI) within the framework of Hall MHD has been limited to configurations with uniform magnetic fields and/or with the magnetic field perpendicular to the sheared ion flow (( B_0⊥ v0 )).(E. N. Opp et al., Phys. Fluids B), 3, 885 (1990)^,(M. Fujimoto et al., J. Geophys. Res.), 96, 15725 (1991)^,(J. D. Huba, Phys. Rev. Lett.), 72, 2033 (1994) Here, we are concerned with the effects of Hall physics in configurations in which (B_0allel v0 ) and both are sheared.(L. Chacon et al, Phys. Lett. A), submitted (2002) In resistive MHD, and for this configuration, either the tearing mode instability (TMI) or the KHI instability dominates depending upon their relative strength.( R. B. Dahlburg et al., Phys. Plasmas), 4, 1213 (1997) In Hall MHD, however, Hall physics decouples the ion and electron flows in a boundary layer of thickness (d_i=c/ω_pi) (ion skin depth), within which electrons are the only magnetized species. Hence, while KHI essentially remains an ion instability, TMI becomes an electron instability. As a result, both KHI and TMI can be unstable simultaneously and interact, creating a very rich linear and nonlinear behavior. This is confirmed by a linear study of the Hall MHD equations. Nonlinearly, both saturated regimes and highly dynamic regimes (with vortex and magnetic island merging) are observed.

  9. Improved Analysis of GW150914 Using a Fully Spin-Precessing Waveform Model

    NASA Astrophysics Data System (ADS)

    Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Adya, V. B.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Aggarwal, N.; Aguiar, O. D.; Aiello, L.; Ain, A.; Ajith, P.; Allen, B.; Allocca, A.; Altin, P. A.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C. C.; Areeda, J. S.; Arnaud, N.; Arun, K. G.; Ascenzi, S.; Ashton, G.; Ast, M.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Babak, S.; Bacon, P.; Bader, M. K. M.; Baker, P. T.; Baldaccini, F.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barclay, S. E.; Barish, B. C.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barta, D.; Bartlett, J.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Baune, C.; Bavigadda, V.; Bazzan, M.; Bejger, M.; Bell, A. S.; Berger, B. K.; Bergmann, G.; Berry, C. P. L.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Bhagwat, S.; Bhandare, R.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Birney, R.; Birnholtz, O.; Biscans, S.; Bisht, A.; Bitossi, M.; Biwer, C.; Bizouard, M. A.; Blackburn, J. K.; Blair, C. D.; Blair, D. G.; Blair, R. M.; Bloemen, S.; Bock, O.; Boer, M.; Bogaert, G.; Bogan, C.; Bohe, A.; Bond, C.; Bondu, F.; Bonnand, R.; Boom, B. A.; Bork, R.; Boschi, V.; Bose, S.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brockill, P.; Broida, J. E.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brown, N. M.; Brunett, S.; Buchanan, C. C.; Buikema, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cabero, M.; Cadonati, L.; Cagnoli, G.; Cahillane, C.; Calderón Bustillo, J.; Callister, T.; Calloni, E.; Camp, J. B.; Cannon, K. C.; Cao, J.; Capano, C. D.; Capocasa, E.; Carbognani, F.; Caride, S.; Casanueva Diaz, C.; Casentini, J.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C. B.; Cerboni Baiardi, L.; Cerretani, G.; Cesarini, E.; Chamberlin, S. J.; Chan, M.; Chao, S.; Charlton, P.; Chassande-Mottin, E.; Cheeseboro, B. D.; Chen, H. Y.; Chen, Y.; Cheng, C.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Cho, M.; Chow, J. H.; Christensen, N.; Chu, Q.; Chua, S.; Chung, S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Collette, C. G.; Cominsky, L.; Constancio, M.; Conte, A.; Conti, L.; Cook, D.; Corbitt, T. R.; Cornish, N.; Corsi, A.; Cortese, S.; Costa, C. A.; Coughlin, M. W.; Coughlin, S. B.; Coulon, J.-P.; Countryman, S. T.; Couvares, P.; Cowan, E. E.; Coward, D. M.; Cowart, M. J.; Coyne, D. C.; Coyne, R.; Craig, K.; Creighton, J. D. E.; Cripe, J.; Crowder, S. G.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dal Canton, T.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Darman, N. S.; Dasgupta, A.; Da Silva Costa, C. F.; Dattilo, V.; Dave, I.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; De, S.; DeBra, D.; Debreczeni, G.; Degallaix, J.; De Laurentis, M.; Deléglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dergachev, V.; De Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Devine, R. C.; Dhurandhar, S.; Díaz, M. C.; Di Fiore, L.; Di Giovanni, M.; Di Girolamo, T.; Di Lieto, A.; Di Pace, S.; Di Palma, I.; Di Virgilio, A.; Dolique, V.; Donovan, F.; Dooley, K. L.; Doravari, S.; Douglas, R.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Ducrot, M.; Dwyer, S. E.; Edo, T. B.; Edwards, M. C.; Effler, A.; Eggenstein, H.-B.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Engels, W.; Essick, R. C.; Etienne, Z.; Etzel, T.; Evans, M.; Evans, T. M.; Everett, R.; Factourovich, M.; Fafone, V.; Fair, H.; Fairhurst, S.; Fan, X.; Fang, Q.; Farinon, S.; Farr, B.; Farr, W. M.; Fauchon-Jones, E.; Favata, M.; Fays, M.; Fehrmann, H.; Fejer, M. M.; Fenyvesi, E.; Ferrante, I.; Ferreira, E. C.; Ferrini, F.; Fidecaro, F.; Fiori, I.; Fiorucci, D.; Fisher, R. P.; Flaminio, R.; Fletcher, M.; Fournier, J.-D.; Frasca, S.; Frasconi, F.; Frei, Z.; Freise, A.; Frey, R.; Frey, V.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gabbard, H. A. G.; Gaebel, S.; Gair, J. R.; Gammaitoni, L.; Gaonkar, S. G.; Garufi, F.; Gaur, G.; Gehrels, N.; Gemme, G.; Geng, P.; Genin, E.; Gennai, A.; George, J.; Gergely, L.; Germain, V.; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, K.; Glaefke, A.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gonzalez Castro, J. M.; Gopakumar, A.; Gordon, N. A.; Gorodetsky, M. L.; Gossan, S. E.; Gosselin, M.; Gouaty, R.; Grado, A.; Graef, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greco, G.; Green, A. C.; Groot, P.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guo, X.; Gupta, A.; Gupta, M. K.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hacker, J. J.; Hall, B. R.; Hall, E. D.; Hammond, G.; Haney, M.; Hanke, M. M.; Hanks, J.; Hanna, C.; Hannam, M. D.; Hanson, J.; Hardwick, T.; Harms, J.; Harry, G. M.; Harry, I. W.; Hart, M. J.; Hartman, M. T.; Haster, C.-J.; Haughian, K.; Healy, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Hennig, J.; Henry, J.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hoak, D.; Hofman, D.; Holt, K.; Holz, D. E.; Hopkins, P.; Hough, J.; Houston, E. A.; Howell, E. J.; Hu, Y. M.; Huang, S.; Huerta, E. A.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Indik, N.; Ingram, D. R.; Inta, R.; Isa, H. N.; Isac, J.-M.; Isi, M.; Isogai, T.; Iyer, B. R.; Izumi, K.; Jacqmin, T.; Jang, H.; Jani, K.; Jaranowski, P.; Jawahar, S.; Jian, L.; Jiménez-Forteza, F.; Johnson, W. W.; Johnson-McDaniel, N. K.; Jones, D. I.; Jones, R.; Jonker, R. J. G.; Ju, L.; K, Haris; Kalaghatgi, C. V.; Kalogera, V.; Kandhasamy, S.; Kang, G.; Kanner, J. B.; Kapadia, S. J.; Karki, S.; Karvinen, K. S.; Kasprzack, M.; Katsavounidis, E.; Katzman, W.; Kaufer, S.; Kaur, T.; Kawabe, K.; Kéfélian, F.; Kehl, M. S.; Keitel, D.; Kelley, D. B.; Kells, W.; Kennedy, R.; Key, J. S.; Khalili, F. Y.; Khan, I.; Khan, S.; Khan, Z.; Khazanov, E. A.; Kijbunchoo, N.; Kim, Chi-Woong; Kim, Chunglee; Kim, J.; Kim, K.; Kim, N.; Kim, W.; Kim, Y.-M.; Kimbrell, S. J.; King, E. J.; King, P. J.; Kissel, J. S.; Klein, B.; Kleybolte, L.; Klimenko, S.; Koehlenbeck, S. M.; Koley, S.; Kondrashov, V.; Kontos, A.; Korobko, M.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Kringel, V.; Królak, A.; Krueger, C.; Kuehn, G.; Kumar, P.; Kumar, R.; Kuo, L.; Kutynia, A.; Lackey, B. D.; Landry, M.; Lange, J.; Lantz, B.; Lasky, P. D.; Laxen, M.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lebigot, E. O.; Lee, C. H.; Lee, H. K.; Lee, H. M.; Lee, K.; Lenon, A.; Leonardi, M.; Leong, J. R.; Leroy, N.; Letendre, N.; Levin, Y.; Lewis, J. B.; Li, T. G. F.; Libson, A.; Littenberg, T. B.; Lockerbie, N. A.; Lombardi, A. L.; London, L. T.; Lord, J. E.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J. D.; Lousto, C. O.; Lovelace, G.; Lück, H.; Lundgren, A. P.; Lynch, R.; Ma, Y.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magaña-Sandoval, F.; Magaña Zertuche, L.; Magee, R. M.; Majorana, E.; Maksimovic, I.; Malvezzi, V.; Man, N.; Mandic, V.; Mangano, V.; Mansell, G. L.; Manske, M.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Markosyan, A. S.; Maros, E.; Martelli, F.; Martellini, L.; Martin, I. W.; Martynov, D. V.; Marx, J. N.; Mason, K.; Masserot, A.; Massinger, T. J.; Masso-Reid, M.; Mastrogiovanni, S.; Matichard, F.; Matone, L.; Mavalvala, N.; Mazumder, N.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McGuire, S. C.; McIntyre, G.; McIver, J.; McManus, D. J.; McRae, T.; McWilliams, S. T.; Meacher, D.; Meadors, G. D.; Meidam, J.; Melatos, A.; Mendell, G.; Mercer, R. A.; Merilh, E. L.; Merzougui, M.; Meshkov, S.; Messenger, C.; Messick, C.; Metzdorff, R.; Meyers, P. M.; Mezzani, F.; Miao, H.; Michel, C.; Middleton, H.; Mikhailov, E. E.; Milano, L.; Miller, A. L.; Miller, A.; Miller, B. B.; Miller, J.; Millhouse, M.; Minenkov, Y.; Ming, J.; Mirshekari, S.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moggi, A.; Mohan, M.; Mohapatra, S. R. P.; Montani, M.; Moore, B. C.; Moore, C. J.; Moraru, D.; Moreno, G.; Morriss, S. R.; Mossavi, K.; Mours, B.; Mow-Lowry, C. M.; Mueller, G.; Muir, A. W.; Mukherjee, Arunava; Mukherjee, D.; Mukherjee, S.; Mukund, N.; Mullavey, A.; Munch, J.; Murphy, D. J.; Murray, P. G.; Mytidis, A.; Nardecchia, I.; Naticchioni, L.; Nayak, R. K.; Nedkova, K.; Nelemans, G.; Nelson, T. J. N.; Neri, M.; Neunzert, A.; Newton, G.; Nguyen, T. T.; Nielsen, A. B.; Nissanke, S.; Nitz, A.; Nocera, F.; Nolting, D.; Normandin, M. E. N.; Nuttall, L. K.; Oberling, J.; Ochsner, E.; O'Dell, J.; Oelker, E.; Ogin, G. H.; Oh, J. J.; Oh, S. H.; Ohme, F.; Oliver, M.; Oppermann, P.; Oram, Richard J.; O'Reilly, B.; O'Shaughnessy, R.; Ottaway, D. J.; Overmier, H.; Owen, B. J.; Pai, A.; Pai, S. A.; Palamos, J. R.; Palashov, O.; Palomba, C.; Pal-Singh, A.; Pan, H.; Pankow, C.; Pannarale, F.; Pant, B. C.; Paoletti, F.; Paoli, A.; Papa, M. A.; Paris, H. R.; Parker, W.; Pascucci, D.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patricelli, B.; Patrick, Z.; Pearlstone, B. L.; Pedraza, M.; Pedurand, R.; Pekowsky, L.; Pele, A.; Penn, S.; Perreca, A.; Perri, L. M.; Pfeiffer, H. P.; Phelps, M.; Piccinni, O. J.; Pichot, M.; Piergiovanni, F.; Pierro, V.; Pillant, G.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Poe, M.; Poggiani, R.; Popolizio, P.; Post, A.; Powell, J.; Prasad, J.; Predoi, V.; Prestegard, T.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prix, R.; Prodi, G. A.; Prokhorov, L.; Puncken, O.; Punturo, M.; Puppo, P.; Pürrer, M.; Qi, H.; Qin, J.; Qiu, S.; Quetschke, V.; Quintero, E. A.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Radkins, H.; Raffai, P.; Raja, S.; Rajan, C.; Rakhmanov, M.; Rapagnani, P.; Raymond, V.; Razzano, M.; Re, V.; Read, J.; Reed, C. M.; Regimbau, T.; Rei, L.; Reid, S.; Reitze, D. H.; Rew, H.; Reyes, S. D.; Ricci, F.; Riles, K.; Rizzo, M.; Robertson, N. A.; Robie, R.; Robinet, F.; Rocchi, A.; Rolland, L.; Rollins, J. G.; Roma, V. J.; Romano, R.; Romanov, G.; Romie, J. H.; Rosińska, D.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.; Sachdev, S.; Sadecki, T.; Sadeghian, L.; Sakellariadou, M.; Salconi, L.; Saleem, M.; Salemi, F.; Samajdar, A.; Sammut, L.; Sanchez, E. J.; Sandberg, V.; Sandeen, B.; Sanders, J. R.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Sauter, O. E. S.; Savage, R. L.; Sawadsky, A.; Schale, P.; Schilling, R.; Schmidt, J.; Schmidt, P.; Schnabel, R.; Schofield, R. M. S.; Schönbeck, A.; Schreiber, E.; Schuette, D.; Schutz, B. F.; Scott, J.; Scott, S. M.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sequino, V.; Sergeev, A.; Setyawati, Y.; Shaddock, D. A.; Shaffer, T.; Shahriar, M. S.; Shaltev, M.; Shapiro, B.; Shawhan, P.; Sheperd, A.; Shoemaker, D. H.; Shoemaker, D. M.; Siellez, K.; Siemens, X.; Sieniawska, M.; Sigg, D.; Silva, A. D.; Singer, A.; Singer, L. P.; Singh, A.; Singh, R.; Singhal, A.; Sintes, A. M.; Slagmolen, B. J. J.; Smith, J. R.; Smith, N. D.; Smith, R. J. E.; Son, E. J.; Sorazu, B.; Sorrentino, F.; Souradeep, T.; Srivastava, A. K.; Staley, A.; Steinke, M.; Steinlechner, J.; Steinlechner, S.; Steinmeyer, D.; Stephens, B. C.; Stevenson, S. P.; Stone, R.; Strain, K. A.; Straniero, N.; Stratta, G.; Strauss, N. A.; Strigin, S.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sun, L.; Sunil, S.; Sutton, P. J.; Swinkels, B. L.; Szczepańczyk, M. J.; Tacca, M.; Talukder, D.; Tanner, D. B.; Tápai, M.; Tarabrin, S. P.; Taracchini, A.; Taylor, R.; Theeg, T.; Thirugnanasambandam, M. P.; Thomas, E. G.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Tiwari, S.; Tiwari, V.; Tokmakov, K. V.; Toland, K.; Tomlinson, C.; Tonelli, M.; Tornasi, Z.; Torres, C. V.; Torrie, C. I.; Töyrä, D.; Travasso, F.; Traylor, G.; Trifirò, D.; Tringali, M. C.; Trozzo, L.; Tse, M.; Turconi, M.; Tuyenbayev, D.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Usman, S. A.; Vahlbruch, H.; Vajente, G.; Valdes, G.; Vallisneri, M.; van Bakel, N.; van Beuzekom, M.; van den Brand, J. F. J.; Van Den Broeck, C.; Vander-Hyde, D. C.; van der Schaaf, L.; van der Sluys, M. V.; van Heijningen, J. V.; Vano-Vinuales, A.; van Veggel, A. A.; Vardaro, M.; Vass, S.; Vasúth, M.; Vaulin, R.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Venkateswara, K.; Verkindt, D.; Vetrano, F.; Viceré, A.; Vinciguerra, S.; Vine, D. J.; Vinet, J.-Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Voss, D. V.; Vousden, W. D.; Vyatchanin, S. P.; Wade, A. R.; Wade, L. E.; Wade, M.; Walker, M.; Wallace, L.; Walsh, S.; Wang, G.; Wang, H.; Wang, M.; Wang, X.; Wang, Y.; Ward, R. L.; Warner, J.; Was, M.; Weaver, B.; Wei, L.-W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.; Weßels, P.; Westphal, T.; Wette, K.; Whelan, J. T.; Whiting, B. F.; Williams, R. D.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M. H.; Winkler, W.; Wipf, C. C.; Wittel, H.; Woan, G.; Woehler, J.; Worden, J.; Wright, J. L.; Wu, D. S.; Wu, G.; Yablon, J.; Yam, W.; Yamamoto, H.; Yancey, C. C.; Yu, H.; Yvert, M.; ZadroŻny, A.; Zangrando, L.; Zanolin, M.; Zendri, J.-P.; Zevin, M.; Zhang, L.; Zhang, M.; Zhang, Y.; Zhao, C.; Zhou, M.; Zhou, Z.; Zhu, X. J.; Zucker, M. E.; Zuraw, S. E.; Zweizig, J.; Boyle, M.; Brügmann, B.; Campanelli, M.; Chu, T.; Clark, M.; Haas, R.; Hemberger, D.; Hinder, I.; Kidder, L. E.; Kinsey, M.; Laguna, P.; Ossokine, S.; Pan, Y.; Röver, C.; Scheel, M.; Szilagyi, B.; Teukolsky, S.; Zlochower, Y.; LIGO Scientific Collaboration; Virgo Collaboration

    2016-10-01

    This paper presents updated estimates of source parameters for GW150914, a binary black-hole coalescence event detected by the Laser Interferometer Gravitational-wave Observatory (LIGO) in 2015 [Abbott et al. Phys. Rev. Lett. 116, 061102 (2016).]. Abbott et al. [Phys. Rev. Lett. 116, 241102 (2016).] presented parameter estimation of the source using a 13-dimensional, phenomenological precessing-spin model (precessing IMRPhenom) and an 11-dimensional nonprecessing effective-one-body (EOB) model calibrated to numerical-relativity simulations, which forces spin alignment (nonprecessing EOBNR). Here, we present new results that include a 15-dimensional precessing-spin waveform model (precessing EOBNR) developed within the EOB formalism. We find good agreement with the parameters estimated previously [Abbott et al. Phys. Rev. Lett. 116, 241102 (2016).], and we quote updated component masses of 35-3+5 M⊙ and 3 0-4+3 M⊙ (where errors correspond to 90% symmetric credible intervals). We also present slightly tighter constraints on the dimensionless spin magnitudes of the two black holes, with a primary spin estimate <0.65 and a secondary spin estimate <0.75 at 90% probability. Abbott et al. [Phys. Rev. Lett. 116, 241102 (2016).] estimated the systematic parameter-extraction errors due to waveform-model uncertainty by combining the posterior probability densities of precessing IMRPhenom and nonprecessing EOBNR. Here, we find that the two precessing-spin models are in closer agreement, suggesting that these systematic errors are smaller than previously quoted.

  10. Review of high pressure phases of calcium by first-principles calculations

    NASA Astrophysics Data System (ADS)

    Ishikawa, T.; Nagara, H.; Suzuki, N.; Tsuchiya, J.; Tsuchiya, T.

    2010-03-01

    We review high pressure phases of calcium which have obtained by recent experimental and first-principles studies. In this study, we investigated the face-centered cubic (fcc) structure, the body-centered cubic (bcc) structure, the simple cubic (sc) structure, a tetragonal P43212 [Ishikawa T et al. 2008 Phys. Rev. B 77 020101(R)], an orthorhombic Cmca [Ishikawa T et al. 2008 Phys. Rev. B 77 020101(R)], an orthorhombic Cmcm [Teweldeberhan A M and Bonev S A 2008 Phys. Rev. B 78 140101(R)], an orthorhombic Pnma [Yao Y et al. 2008 Phys. Rev. B 78 054506] and a tetragonal I4/mcm(00) [Arapan S et al. 2008 Proc. Natl. Acad. Sci. USA 105 20627]. We compared the enthalpies among the structures up to 200 GPa and theoretically determined the phase diagram of calcium. The sequence of the structural transitions is fcc (0- 3.5 GPa) → bcc (3.5 - 35.7 GPa) → Cmcm (35.7- 52GPa) → P43212 (52-109 GPa) → Cmca (109-117.4GPa) → Pnma (117.4-134.6GPa) → I4/mcm(00) (134.6 GPa -). The sc phase is experimentally observed in the pressure range from 32 to 113 GPa but, in our calculation, there is no pressure region where the sc phase is the most stable. In addition, we found that the enthalpy of the hexagonal close-packed (hcp) structure is lower than that of I4/mcm(00) above 495 GPa.

  11. Avalanche boron fusion by laser picosecond block ignition with magnetic trapping for clean and economic reactor

    DOE PAGES

    Hora, H.; Korn, G.; Eliezer, S.; ...

    2016-10-11

    Measured highly elevated gains of proton–boron (HB11) fusion (Picciottoet al., Phys. Rev. X4, 031030 (2014)) confirmed the exceptional avalanche reaction process (Lalousiset al., Laser Part. Beams 32, 409 (2014); Horaet al., Laser Part. Beams33, 607 (2015)) for the combination of the non-thermal block ignition using ultrahigh intensity laser pulses of picoseconds duration. The ultrahigh accelerationabovemore » $$10^{20}~\\text{cm}~\\text{s}^{-2}$$ for plasma blocks was theoretically and numerically predicted since 1978 (Hora,Physics of Laser Driven Plasmas(Wiley, 1981), pp. 178 and 179) and measured (Sauerbrey, Phys. Plasmas3, 4712 (1996)) in exact agreement (Horaet al., Phys. Plasmas14, 072701 (2007)) when the dominating force was overcoming thermal processes. This is based on Maxwell’s stress tensor by the dielectric properties of plasma leading to the nonlinear (ponderomotive) force $$f_{\\text{NL}}$$ resulting in ultra-fast expanding plasma blocks by a dielectric explosion. Combining this with measured ultrahigh magnetic fields and the avalanche process opens an option for an environmentally absolute clean and economic boron fusion power reactor. Finally, this is supported also by other experiments with very high HB11 reactions under different conditions (Labauneet al., Nature Commun.4, 2506 (2013)).« less

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hora, H.; Korn, G.; Eliezer, S.

    Measured highly elevated gains of proton–boron (HB11) fusion (Picciottoet al., Phys. Rev. X4, 031030 (2014)) confirmed the exceptional avalanche reaction process (Lalousiset al., Laser Part. Beams 32, 409 (2014); Horaet al., Laser Part. Beams33, 607 (2015)) for the combination of the non-thermal block ignition using ultrahigh intensity laser pulses of picoseconds duration. The ultrahigh accelerationabovemore » $$10^{20}~\\text{cm}~\\text{s}^{-2}$$ for plasma blocks was theoretically and numerically predicted since 1978 (Hora,Physics of Laser Driven Plasmas(Wiley, 1981), pp. 178 and 179) and measured (Sauerbrey, Phys. Plasmas3, 4712 (1996)) in exact agreement (Horaet al., Phys. Plasmas14, 072701 (2007)) when the dominating force was overcoming thermal processes. This is based on Maxwell’s stress tensor by the dielectric properties of plasma leading to the nonlinear (ponderomotive) force $$f_{\\text{NL}}$$ resulting in ultra-fast expanding plasma blocks by a dielectric explosion. Combining this with measured ultrahigh magnetic fields and the avalanche process opens an option for an environmentally absolute clean and economic boron fusion power reactor. Finally, this is supported also by other experiments with very high HB11 reactions under different conditions (Labauneet al., Nature Commun.4, 2506 (2013)).« less

  13. Thermal Modeling of Al-Al and Al-Steel Friction Stir Spot Welding

    NASA Astrophysics Data System (ADS)

    Jedrasiak, P.; Shercliff, H. R.; Reilly, A.; McShane, G. J.; Chen, Y. C.; Wang, L.; Robson, J.; Prangnell, P.

    2016-09-01

    This paper presents a finite element thermal model for similar and dissimilar alloy friction stir spot welding (FSSW). The model is calibrated and validated using instrumented lap joints in Al-Al and Al-Fe automotive sheet alloys. The model successfully predicts the thermal histories for a range of process conditions. The resulting temperature histories are used to predict the growth of intermetallic phases at the interface in Al-Fe welds. Temperature predictions were used to study the evolution of hardness of a precipitation-hardened aluminum alloy during post-weld aging after FSSW.

  14. Bulk modulus of two-dimensional liquid dusty plasmas and its application

    NASA Astrophysics Data System (ADS)

    Li, Wei; Lin, Wei; Feng, Yan

    2017-04-01

    From the recently obtained equation of state [Feng et al., J. Phys. D: Appl. Phys. 49, 235203 (2016) and Feng et al., Phys. Plasmas 23, 093705 (2016); Erratum 23, 119904 (2016)], the bulk modulus of elasticity K of 2D liquid dusty plasmas is analytically derived as the expression of the temperature and the screening parameter. Exact values of the obtained bulk modulus of elasticity K are reported and also plotted in the 2D plane of the temperature and the screening parameter. As the temperature and the screening parameter change, the variation trend of K is reported and the corresponding interpretation is suggested. It has been demonstrated that the obtained bulk modulus of elasticity K can be used to predict the longitudinal sound speed, which agrees well with previous studies.

  15. Proton irradiation studies on Al and Al5083 alloy

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, P.; Gayathri, N.; Bhattacharya, M.; Gupta, A. Dutta; Sarkar, Apu; Dhar, S.; Mitra, M. K.; Mukherjee, P.

    2017-10-01

    The change in the microstructural parameters and microhardness values in 6.5 MeV proton irradiated pure Al and Al5083 alloy samples have been evaluated using different model based techniques of X-ray diffraction Line Profile Analysis (XRD) and microindendation techniques. The detailed line profile analysis of the XRD data showed that the domain size increases and saturates with irradiation dose both in the case of Al and Al5083 alloy. The corresponding microstrain values did not show any change with irradiation dose in the case of the pure Al but showed an increase at higher irradiation doses in the case of Al5083 alloy. The microindendation results showed that unirradiated Al5083 alloy has higher hardness value compared to that of unirradiated pure Al. The hardness increased marginally with irradiation dose in the case of Al5083, whereas for pure Al, there was no significant change with dose.

  16. Optical Spin Initialization and Nondestructive Measurement in a Quantum Dot Molecule

    DTIC Science & Technology

    2008-12-02

    in fre- quency domain [7], and coherent spin rotations in time domain [8,9]). We thank M. F. Doty and V. L. Korenev for illuminating discussions...035409 (2007). [29] V. L. Korenev , Phys. Rev. Lett. 99, 256405 (2007). [30] A. I. Tartakovskii et al., Phys. Rev. Lett. 98, 026806 (2007). [31] A

  17. Demonstration of Flying Mirror with Improved Efficiency

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pirozhkov, Alexander S.; Kando, Masaki; Fukuda, Yuji

    2009-07-25

    A strongly nonlinear wake wave driven by an intense laser pulse can act as a partially reflecting relativistic mirror (the flying mirror)[S. V. Bulanov, et al., Bulletin of the Lebedev Physics Institute, No. 6, 9 (1991); S. V. Bulanov, et al., Phys. Rev. Lett. 91, 085001 (2003)]. Upon reflection from such mirror, a counter-propagating optical-frequency laser pulse is directly converted into high-frequency radiation, with a frequency multiplication factor approx4gamma{sup 2}(the double Doppler effect). We present the results of recent experiment in which the photon number in the reflected radiation was at least several thousand times larger than in our proof-of-principlemore » experiment [M. Kando, et al., Phys. Rev. Lett. 99, 135001 (2007); A. S. Pirozhkov, et al., Phys. Plasmas 14, 123106 (2007)]. The flying mirror holds promise of generating intense coherent ultrashort XUV and x-ray pulses that inherit their temporal shape and polarization from the original optical-frequency (laser) pulses. Furthermore, the reflected radiation bears important information about the reflecting wake wave itself, which can be used for its diagnostics.« less

  18. Effect of anomalous transport on kinetic simulations of the H-mode pedestal

    NASA Astrophysics Data System (ADS)

    Bateman, G.; Pankin, A. Y.; Kritz, A. H.; Rafiq, T.; Park, G. Y.; Ku, S.; Chang, C. S.

    2009-11-01

    The MMM08 and MMM95 Multi-Mode transport models [1,2], are used to investigate the effect of anomalous transport in XGC0 gyrokinetic simulations [3] of tokamak H-mode pedestal growth. Transport models are implemented in XGC0 using the Framework for Modernization and Componentization of Fusion Modules (FMCFM). Anomalous transport is driven by steep temperature and density gradients and is suppressed by high values of flow shear in the pedestal. The radial electric field, used to calculate the flow shear rate, is computed self-consistently in the XGC0 code with the anomalous transport, Lagrangian charged particle dynamics and neutral particle effects. XGC0 simulations are used to provide insight into how thermal and particle transport, together with the sources of heat and charged particles, determine the shape and growth rate of the temperature and density profiles. [1] F.D. Halpern et al., Phys. Plasmas 15 (2008) 065033; J.Weiland et al., Nucl. Fusion 49 (2009) 965933; A.Kritz et al., EPS (2009) [2] G. Bateman, et al, Phys. Plasmas 5 (1998) 1793 [3] C.S. Chang, S. Ku, H. Weitzner, Phys. Plasmas 11 (2004) 2649

  19. Impact of a new wavelength-dependent representation of methane photolysis branching ratios on the modeling of Titan’s atmospheric photochemistry

    NASA Astrophysics Data System (ADS)

    Gans, B.; Peng, Z.; Carrasco, N.; Gauyacq, D.; Lebonnois, S.; Pernot, P.

    2013-03-01

    A new wavelength-dependent model for CH4 photolysis branching ratios is proposed, based on the values measured recently by Gans et al. (Gans, B. et al. [2011]. Phys. Chem. Chem. Phys. 13, 8140-8152). We quantify the impact of this representation on the predictions of a photochemical model of Titan’s atmosphere, on their precision, and compare to earlier representations. Although the observed effects on the mole fraction of the species are small (never larger than 50%), it is possible to draw some recommendations for further studies: (i) the Ly-α branching ratios of Wang et al. (Wang, J.H. et al. [2000]. J. Chem. Phys. 113, 4146-4152) used in recent models overestimate the CH2:CH3 ratio, a factor to which a lot of species are sensitive; (ii) the description of out-of-Ly-α branching ratios by the “100% CH3” scenario has to be avoided, as it can bias significantly the mole fractions of some important species (C3H8); and (iii) complementary experimental data in the 130-140 nm range would be useful to constrain the models in the Ly-α deprived 500-700 km altitude range.

  20. Higher velocity, high-foot implosions on the National Ignition Facility laser

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Callahan, D. A.; Hurricane, O. A.; Hinkel, D. E.

    By increasing the velocity in “high foot” implosions [Dittrich et al., Phys. Rev. Lett. 112, 055002 (2014); Park et al., Phys. Rev. Lett. 112, 055001 (2014); Hurricane et al., Nature 506, 343 (2014); Hurricane et al., Phys. Plasmas 21, 056314 (2014)] on the National Ignition Facility laser, we have nearly doubled the neutron yield and the hotspot pressure as compared to the implosions reported upon last year. The implosion velocity has been increased using a combination of the laser (higher power and energy), the hohlraum (depleted uranium wall material with higher opacity and lower specific heat than gold hohlraums), andmore » the capsule (thinner capsules with less mass). We find that the neutron yield from these experiments scales systematically with a velocity-like parameter of the square root of the laser energy divided by the ablator mass. By connecting this parameter with the inferred implosion velocity (v), we find that for shots with primary yield >1e15 neutrons, the total yield ~ v⁹˙⁴. This increase is considerably faster than the expected dependence for implosions without alpha heating ( ~v⁵˙⁹) and is additional evidence that these experiments have significant alpha heating.« less

  1. Higher velocity, high-foot implosions on the National Ignition Facility laser

    DOE PAGES

    Callahan, D. A.; Hurricane, O. A.; Hinkel, D. E.; ...

    2015-05-15

    By increasing the velocity in “high foot” implosions [Dittrich et al., Phys. Rev. Lett. 112, 055002 (2014); Park et al., Phys. Rev. Lett. 112, 055001 (2014); Hurricane et al., Nature 506, 343 (2014); Hurricane et al., Phys. Plasmas 21, 056314 (2014)] on the National Ignition Facility laser, we have nearly doubled the neutron yield and the hotspot pressure as compared to the implosions reported upon last year. The implosion velocity has been increased using a combination of the laser (higher power and energy), the hohlraum (depleted uranium wall material with higher opacity and lower specific heat than gold hohlraums), andmore » the capsule (thinner capsules with less mass). We find that the neutron yield from these experiments scales systematically with a velocity-like parameter of the square root of the laser energy divided by the ablator mass. By connecting this parameter with the inferred implosion velocity (v), we find that for shots with primary yield >1e15 neutrons, the total yield ~ v⁹˙⁴. This increase is considerably faster than the expected dependence for implosions without alpha heating ( ~v⁵˙⁹) and is additional evidence that these experiments have significant alpha heating.« less

  2. Determination of π± meson polarizabilities from the γγ→π+π- process

    NASA Astrophysics Data System (ADS)

    Fil'Kov, L. V.; Kashevarov, V. L.

    2006-03-01

    A fit of the experimental data to the total cross section of the process γγ→π+π- in the energy region from threshold to 2500 MeV has been carried out using dispersion relations with subtractions for the invariant amplitudes, where the dipole and the quadrupole polarizabilities of the charged pion are free parameters. As a result, the sum and the difference of the electric and magnetic dipole and quadrupole polarizabilities of the charged pion have been found: (α1+β1)π±=(0.18-0.02+0.11)×10-4fm3,(α1-β1)π±=(13.0-1.9+2.6)×10-4fm3,(α2+β2)π±=(0.133±0.015)×10-4fm5,(α2-β2)π±=(25.0-0.3+0.8)×10-4fm5. These values agree with the dispersion sum rule predictions. The value found for the difference of the dipole polarizabilities is consistent with the results obtained from scattering of high energy π- mesons off the Coulomb field of heavy nuclei [Yu. M. Antipov , Phys. Lett. B121, 445 (1983)] and from radiative π+ photoproduction from the proton at MAMI [J. Ahrens , Eur. Phys. J. A 23, 113 (2005)], whereas it is at variance with the recent calculations in the framework of chiral perturbation theory.

  3. Ionospheric Storm Effects at Subauroral Latitudes: A Case Study

    DTIC Science & Technology

    1991-02-01

    Island: Z70 m/s) are consistent with corresponding model predictions [e.g., Testud et al., 1975: Richmond and Marsushitl, 1975]. Note that while...Atmos. Terr. Phys., 44. 161-171. 1982. in the morning sector. There it is marked by an anomalously Alcayde. D.. J. Testud . G. Vasseur. and P. Wadteufel...34-pile up" F-region trough. J. Atmos. Terr. Phys.. 33. 647-656. 1973. in the F-region. J. Atmos. Terr. Phys., 36, 70 -706. 1974. Testud . J.. P. Amayenc

  4. Low Work Function Csl Coatings for Enhanced Field Emission Properties

    DTIC Science & Technology

    2011-04-01

    CsI is an insulator band gap=6.2 eV Ref. 6 that would be expected to impede, rather than to enhance, electron tunneling. Vlahos et al.7...minimal WF. Vlahos et al.10 later carried out ex situ experimental char- acterization of the surfaces of CsI-coated cathodes after use in a FE device...Jenkin, J. Liesegang, and R. C. G. Leckey, Phys. Rev. B 11, 5179 1975. 7V. Vlahos , J. H. Booske, and D. Morgan, Appl. Phys. Lett. 91, 144102 2007. 8A

  5. Compilation of NRL Publications on High Temperature Superconductivity.

    DTIC Science & Technology

    1987-01-01

    Fig. 2. The upper critical field as a function of .R. Beasley: Phys. Rev 11(1979) 4545. temperature for Ial.8Sro.2Cu04 (left) and 10) A. Junod , A...commuication 10) T.P. Orlando. E.J. McNiff. Jr.. S. Foner. and M.R. Beasley: Fhys. Rev 9(1979) 4545.-,, 11) A. Junod . A. Bezinge. T. Graf. J.L. Jorda. J...of MRS meeting (Anaheim, i Uchida et al. Jpn. J. of Apph Phys. 26, L443 (1987). -s 1987; in press). 12. H. Junod et al. (preprint

  6. The Production and Study of Cold Antiprotons and Antihydrogen

    DTIC Science & Technology

    2015-08-03

    Grafström, R. Hagel- berg, G. Kessler, and et al ., Phys. Lett. B 237, 303 (1990). [8] C. Zimmermann and T. Hänsch, Hyperfine Interact. 76, 47 (1993). [9...C. Parthey, A. Matveev, J. Alnis, B. Bernhardt, A. Beyer, R. Holzwarth, A. Maistrou, R. Pohl, K. Pre- dehl, T. Udem, T. Wilken, N. Kolachevsky, et al ...D. Lett, R. N. Watts, C. I. Westbrook, W. D. Phillips, P. L. Gould , and H. J. Metcalf, Phys. Rev. Lett. 61, 169 ( 1988 ). [15] J. Walz and T. Hänsch

  7. Relativistic quantum private database queries

    NASA Astrophysics Data System (ADS)

    Sun, Si-Jia; Yang, Yu-Guang; Zhang, Ming-Ou

    2015-04-01

    Recently, Jakobi et al. (Phys Rev A 83, 022301, 2011) suggested the first practical private database query protocol (J-protocol) based on the Scarani et al. (Phys Rev Lett 92, 057901, 2004) quantum key distribution protocol. Unfortunately, the J-protocol is just a cheat-sensitive private database query protocol. In this paper, we present an idealized relativistic quantum private database query protocol based on Minkowski causality and the properties of quantum information. Also, we prove that the protocol is secure in terms of the user security and the database security.

  8. Classification of Four-Qubit States by Means of a Stochastic Local Operation and the Classical Communication Invariant

    NASA Astrophysics Data System (ADS)

    Zha, Xin-Wei; Ma, Gang-Long

    2011-02-01

    It is a recent observation that entanglement classification for qubits is closely related to stochastic local operations and classical communication (SLOCC) invariants. Verstraete et al.[Phys. Rev. A 65 (2002) 052112] showed that for pure states of four qubits there are nine different degenerate SLOCC entanglement classes. Li et al.[Phys. Rev. A 76 (2007) 052311] showed that there are at feast 28 distinct true SLOCC entanglement classes for four qubits by means of the SLOCC invariant and semi-invariant. We give 16 different entanglement classes for four qubits by means of basic SLOCC invariants.

  9. Trapped-Particle Instability Leading to Bursting in Stimulated Raman Scattering Simulations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    S. Brunner; E. Valeo

    2001-11-08

    Nonlinear, kinetic simulations of Stimulated Raman Scattering (SRS) for laser-fusion-relevant conditions present a bursting behavior. Different explanations for this regime has been given in previous studies: Saturation of SRS by increased nonlinear Landau damping [K. Estabrook et al., Phys. Fluids B 1 (1989) 1282] and detuning due to the nonlinear frequency shift of the plasma wave [H.X. Vu et al., Phys. Rev. Lett. 86 (2001) 4306]. Another mechanism, also assigning a key role to the trapped electrons, is proposed here: The break-up of the plasma wave through the trapped-particle instability.

  10. Validity of Vegard’s rule for Al1-xInxN (0.08  <  x  <  0.28) thin films grown on GaN templates

    NASA Astrophysics Data System (ADS)

    Magalhães, S.; Franco, N.; Watson, I. M.; Martin, R. W.; O'Donnell, K. P.; Schenk, H. P. D.; Tang, F.; Sadler, T. C.; Kappers, M. J.; Oliver, R. A.; Monteiro, T.; Martin, T. L.; Bagot, P. A. J.; Moody, M. P.; Alves, E.; Lorenz, K.

    2017-05-01

    In this work, comparative x-ray diffraction (XRD) and Rutherford backscattering spectrometry (RBS) measurements allow a comprehensive characterization of Al1-xInxN thin films grown on GaN. Within the limits of experimental accuracy, and in the compositional range 0.08  <  x  <  0.28, the lattice parameters of the alloys generally obey Vegard’s rule, varying linearly with the InN fraction. Results are also consistent with the small deviation from linear behaviour suggested by Darakchieva et al (2008 Appl. Phys. Lett. 93 261908). However, unintentional incorporation of Ga, revealed by atom probe tomography (APT) at levels below the detection limit for RBS, may also affect the lattice parameters. Furthermore, in certain samples the compositions determined by XRD and RBS differ significantly. This fact, which was interpreted in earlier publications as an indication of a deviation from Vegard’s rule, may rather be ascribed to the influence of defects or impurities on the lattice parameters of the alloy. The wide-ranging set of Al1-xInxN films studied allowed furthermore a detailed investigation of the composition leading to lattice-matching of Al1-xInxN/GaN bilayers.

  11. A review of laser-plasma interaction physics of indirect-drive fusion

    NASA Astrophysics Data System (ADS)

    Kirkwood, R. K.; Moody, J. D.; Kline, J.; Dewald, E.; Glenzer, S.; Divol, L.; Michel, P.; Hinkel, D.; Berger, R.; Williams, E.; Milovich, J.; Yin, L.; Rose, H.; MacGowan, B.; Landen, O.; Rosen, M.; Lindl, J.

    2013-10-01

    The National Ignition Facility (NIF) has been designed, constructed and has recently begun operation to investigate the ignition of nuclear fusion with a laser with up to 1.8 MJ of energy per pulse. The concept for fusion ignition on the NIF, as first proposed in 1990, was based on an indirectly driven spherical capsule of fuel in a high-Z hohlraum cavity filled with low-Z gas (Lindl et al 2004 Phys. Plasmas 11 339). The incident laser energy is converted to x-rays with keV energy on the hohlraums interior wall. The x-rays then impinge on the surface of the capsule, imploding it and producing the fuel conditions needed for ignition. It was recognized at the inception that this approach would potentially be susceptible to scattering of the incident light by the plasma created in the gas and the ablated material in the hohlraum interior. Prior to initial NIF operations, expectations for laser-plasma interaction (LPI) in ignition-scale experiments were based on experimentally benchmarked simulations and models of the plasma effects that had been carried out as part of the original proposal for NIF and expanded during the 13-year design and construction period. The studies developed the understanding of the stimulated Brillouin scatter, stimulated Raman scatter and filamentation that can be driven by the intense beams. These processes produce scatter primarily in both the forward and backward direction, and by both individual beams and collective interaction of multiple beams. Processes such as hot electron production and plasma formation and transport were also studied. The understanding of the processes so developed was the basis for the design and planning of the recent experiments in the ignition campaign at NIF, and not only indicated that the plasma instabilities could be controlled to maximize coupling, but predicted that, for the first time, they would be beneficial in controlling drive symmetry. The understanding is also now a critical component in the

  12. Combustion synthesis of AlB2-Al2O3 composite powders with AlB2 nanowire structures

    NASA Astrophysics Data System (ADS)

    Yang, Pan; Xiao, Guoqing; Ding, Donghai; Ren, Yun; Yang, Shoulei; Lv, Lihua; Hou, Xing

    2018-05-01

    Using of Al and B2O3 powders as starting materials, and Mg-Al alloy as additives, AlB2-Al2O3 composite powders with AlB2 nanowire structures were successfully fabricated via combustion synthesis method in Ar atmosphere at a pressure of 1.5 MPa. The effect of different amount of Mg-Al alloy on the phase compositions and morphology of the combustion products was investigated. The results revealed that AlB2 and Al2O3 increased, whereas Al decreased with the content of Mg-Al alloy increasing. The impurities MgAl2O4 and AlB12 would exist in the sample with adding of 18 wt% Mg-Al alloy. Interestingly, FESEM/TEM/EDS results showed that AlB2 nanowires were observed in the products when the content of Mg-Al alloy is 6 wt% and 12 wt%. The more AlB2 nanowires can be found as the content of Mg-Al alloy increased. And the yield of AlB2 nanowires with the diameter of about 200 nanometers (nm) and the length up to several tens of micrometers (μm) in the combustion product is highest when the content of Mg-Al alloy is 12 wt%. The vapor, such as Mg-Al (g), B2O2 (g), AlO (g) and Al2O (g), produced during the process of combustion synthesis, reacted with each other to yield AlB2 nanowires by vapor-solid (VS) mechanism and the corresponding model was also proposed.

  13. New “Tau-Leap” Strategy for Accelerated Stochastic Simulation

    PubMed Central

    2015-01-01

    The “Tau-Leap” strategy for stochastic simulations of chemical reaction systems due to Gillespie and co-workers has had considerable impact on various applications. This strategy is reexamined with Chebyshev’s inequality for random variables as it provides a rigorous probabilistic basis for a measured τ-leap thus adding significantly to simulation efficiency. It is also shown that existing strategies for simulation times have no probabilistic assurance that they satisfy the τ-leap criterion while the use of Chebyshev’s inequality leads to a specified degree of certainty with which the τ-leap criterion is satisfied. This reduces the loss of sample paths which do not comply with the τ-leap criterion. The performance of the present algorithm is assessed, with respect to one discussed by Cao et al. (J. Chem. Phys.2006, 124, 044109), a second pertaining to binomial leap (Tian and Burrage J. Chem. Phys.2004, 121, 10356; Chatterjee et al. J. Chem. Phys.2005, 122, 024112; Peng et al. J. Chem. Phys.2007, 126, 224109), and a third regarding the midpoint Poisson leap (Peng et al., 2007; Gillespie J. Chem. Phys.2001, 115, 1716). The performance assessment is made by estimating the error in the histogram measured against that obtained with the so-called stochastic simulation algorithm. It is shown that the current algorithm displays notably less histogram error than its predecessor for a fixed computation time and, conversely, less computation time for a fixed accuracy. This computational advantage is an asset in repetitive calculations essential for modeling stochastic systems. The importance of stochastic simulations is derived from diverse areas of application in physical and biological sciences, process systems, and economics, etc. Computational improvements such as those reported herein are therefore of considerable significance. PMID:25620846

  14. New "Tau-Leap" Strategy for Accelerated Stochastic Simulation.

    PubMed

    Ramkrishna, Doraiswami; Shu, Che-Chi; Tran, Vu

    2014-12-10

    The "Tau-Leap" strategy for stochastic simulations of chemical reaction systems due to Gillespie and co-workers has had considerable impact on various applications. This strategy is reexamined with Chebyshev's inequality for random variables as it provides a rigorous probabilistic basis for a measured τ-leap thus adding significantly to simulation efficiency. It is also shown that existing strategies for simulation times have no probabilistic assurance that they satisfy the τ-leap criterion while the use of Chebyshev's inequality leads to a specified degree of certainty with which the τ-leap criterion is satisfied. This reduces the loss of sample paths which do not comply with the τ-leap criterion. The performance of the present algorithm is assessed, with respect to one discussed by Cao et al. ( J. Chem. Phys. 2006 , 124 , 044109), a second pertaining to binomial leap (Tian and Burrage J. Chem. Phys. 2004 , 121 , 10356; Chatterjee et al. J. Chem. Phys. 2005 , 122 , 024112; Peng et al. J. Chem. Phys. 2007 , 126 , 224109), and a third regarding the midpoint Poisson leap (Peng et al., 2007; Gillespie J. Chem. Phys. 2001 , 115 , 1716). The performance assessment is made by estimating the error in the histogram measured against that obtained with the so-called stochastic simulation algorithm. It is shown that the current algorithm displays notably less histogram error than its predecessor for a fixed computation time and, conversely, less computation time for a fixed accuracy. This computational advantage is an asset in repetitive calculations essential for modeling stochastic systems. The importance of stochastic simulations is derived from diverse areas of application in physical and biological sciences, process systems, and economics, etc. Computational improvements such as those reported herein are therefore of considerable significance.

  15. Totally Asymmetric Limit for Models of Heat Conduction

    NASA Astrophysics Data System (ADS)

    De Carlo, Leonardo; Gabrielli, Davide

    2017-08-01

    We consider one dimensional weakly asymmetric boundary driven models of heat conduction. In the cases of a constant diffusion coefficient and of a quadratic mobility we compute the quasi-potential that is a non local functional obtained by the solution of a variational problem. This is done using the dynamic variational approach of the macroscopic fluctuation theory (Bertini et al. in Rev Mod Phys 87:593, 2015). The case of a concave mobility corresponds essentially to the exclusion model that has been discussed in Bertini et al. (J Stat Mech L11001, 2010; Pure Appl Math 64(5):649-696, 2011; Commun Math Phys 289(1):311-334, 2009) and Enaud and Derrida (J Stat Phys 114:537-562, 2004). We consider here the convex case that includes for example the Kipnis-Marchioro-Presutti (KMP) model and its dual (KMPd) (Kipnis et al. in J Stat Phys 27:6574, 1982). This extends to the weakly asymmetric regime the computations in Bertini et al. (J Stat Phys 121(5/6):843-885, 2005). We consider then, both microscopically and macroscopically, the limit of large externalfields. Microscopically we discuss some possible totally asymmetric limits of the KMP model. In one case the totally asymmetric dynamics has a product invariant measure. Another possible limit dynamics has instead a non trivial invariant measure for which we give a duality representation. Macroscopically we show that the quasi-potentials of KMP and KMPd, which are non local for any value of the external field, become local in the limit. Moreover the dependence on one of the external reservoirs disappears. For models having strictly positive quadratic mobilities we obtain instead in the limit a non local functional having a structure similar to the one of the boundary driven asymmetric exclusion process.

  16. Interfacial Phenomena in Al/Al, Al/Cu, and Cu/Cu Joints Soldered Using an Al-Zn Alloy with Ag or Cu Additions

    NASA Astrophysics Data System (ADS)

    Pstruś, Janusz; Gancarz, Tomasz

    2014-05-01

    The studies of soldered joints were carried out in systems: Al/solder/Al, Al/solder/Cu, Cu/solder/Cu, where the solder was (Al-Zn)EUT, (Al-Zn)EUT with 0.5, 1.0, and 1.5 at.% of Ag and (Al-Zn)EUT with 0.5, 1.0, and 1.5 at.% of Cu addition. Brazing was performed at 500 °C for 3 min. The EDS analysis indicated that the composition of the layers starting from the Cu pad was CuZn, Cu5Zn8, and CuZn4, respectively. Wetting tests were performed at 500 °C for 3, 8, 15, and 30 min, respectively. Thickness of the layers and their kinetics of growth were measured based on the SEM micrographs. The formation of interlayers was not observed from the side of Al pads. On the contrary, dissolution of the Al substrate and migration of Al-rich particles into the bulk of the solder were observed.

  17. Self-excitation of single nanomechanical pillars

    NASA Astrophysics Data System (ADS)

    Kim, Hyun S.; Qin, Hua; Blick, Robert H.

    2010-03-01

    Self-excitation is a mechanism that is ubiquitous for electromechanical power devices such as electrical generators. This is conventionally achieved by making use of the magnetic field component in electrical generators (Nedic and Lipo 2000 IEEE/IAS Conf. Records (Rome, Italy) vol 1 pp 51-6), a good and widely visible example of which is the wind turbine farm (Muljadi et al 2005 J. Sol. Energy Eng. 127 581-7). In other words, a static force, such as the wind acting on rotor blades, can generate a resonant excitation at a certain mechanical frequency. For nanomechanical systems (Craighead 2000 Science 290 1532-5 Roukes 2001 Phys. World 14 25-31 Cleland 2003 Foundations of Nanomechanics (Berlin: Springer); Ayari et al 2007 Nano Lett. 7 2252-7 Koenig et al 2008 Nat. Nanotechnol. 3 482-4) such a self-excitation (SE) mechanism is also highly desirable, because it can generate mechanical oscillations at radio frequencies by simply applying a dc bias voltage. This is of great importance for low-power signal communication devices and detectors, as well as for mechanical computing elements. For a particular nanomechanical system—the single electron shuttle—this effect was predicted some time ago by Gorelik et al (Phys. Rev. Lett. 80 4526-9). Here, we use a nanoelectromechanical single electron transistor (NEMSET) to demonstrate self-excitation for both the soft and hard regimes, respectively. The ability to use self-excitation in nanomechanical systems may enable the detection of quantum mechanical backaction effects (Naik et al 2006 Nature 443 193-6) in direct tunneling, macroscopic quantum tunneling (Savelev et al 2006 New J. Phys. 8 105-15) and rectification (Pistolesi and Fazio 2005 Phys. Rev. Lett. 94 036806-4). All these effects have so far been overshadowed by the large driving voltages that had to be applied.

  18. Orientation relationship of eutectoid FeAl and FeAl2.

    PubMed

    Scherf, A; Kauffmann, A; Kauffmann-Weiss, S; Scherer, T; Li, X; Stein, F; Heilmaier, M

    2016-04-01

    Fe-Al alloys in the aluminium range of 55-65 at.% exhibit a lamellar microstructure of B2-ordered FeAl and triclinic FeAl 2 , which is caused by a eutectoid decomposition of the high-temperature Fe 5 Al 8 phase, the so-called ∊ phase. The orientation relationship of FeAl and FeAl 2 has previously been studied by Bastin et al. [ J. Cryst. Growth (1978 ▸), 43 , 745] and Hirata et al. [ Philos. Mag. Lett. (2008 ▸), 88 , 491]. Since both results are based on different crystallographic data regarding FeAl 2 , the data are re-evaluated with respect to a recent re-determination of the FeAl 2 phase provided by Chumak et al. [ Acta Cryst. (2010 ▸), C 66 , i87]. It is found that both orientation relationships match subsequent to a rotation operation of 180° about a 〈112〉 crystallographic axis of FeAl or by applying the inversion symmetry of the FeAl 2 crystal structure as suggested by the Chumak data set. Experimental evidence for the validity of the previously determined orientation relationships was found in as-cast fully lamellar material (random texture) as well as directionally solidified material (∼〈110〉 FeAl || solidification direction) by means of orientation imaging microscopy and global texture measurements. In addition, a preferential interface between FeAl and FeAl 2 was identified by means of trace analyses using cross sectioning with a focused ion beam. On the basis of these habit planes the orientation relationship between the two phases can be described by ([Formula: see text]01) FeAl || (114)[Formula: see text] and [111] FeAl || [1[Formula: see text]0][Formula: see text]. There is no evidence for twinning within FeAl lamellae or alternating orientations of FeAl lamellae. Based on the determined orientation and interface data, an atomistic model of the structure relationship of Fe 5 Al 8 , FeAl and FeAl 2 in the vicinity of the eutectoid decomposition is derived. This model is analysed with respect to the strain which has to be

  19. Improved Analytical Potentials for the a ^3Σu+ and X ^1Σg+ States of {Cs_2}

    NASA Astrophysics Data System (ADS)

    Baldwin, Jesse; Le Roy, Robert J.

    2012-06-01

    Recent studies of the collisional properties of ultracold Cs atoms have led to a renewed interest in the singlet and triplet ground-state potential energy functions of Cs_2. Coxon and Hajigeorgiou recently determined an analytic potential function for the X ^1Σ_g^+ state that accurately reproduces a large body of spectroscopic data that spanned 99.45% of the potential well. However, their potential explicitly incorporates only the three leading inverse-power terms in the long-range potential, and does not distinguish between the three asymptotes associated with the different Cs atom spin states. Similarly, Xie et al. have reported two versions of an analytic potential energy function for the a ^3Σ_u^+ state that they determined from direct potential fits to emission data that spanned 93 % of its potential energy well. However, the tail of their potential function model was not constrained to have the inverse-power-sum form required by theory. Moreover, a physically correct description of cold atom collision phenomena requires the long-range inverse-power tails of these two potentials to be identical, and they are not. Thus, these functions cannot be expected to describe cold atom collision properties correctly. The present paper describes our efforts to determine improved analytic potential energy functions for these states that have identical long-range tails, and fully represent all of the spectroscopic data used in the earlier worka,b,c as well as photoassociation data that was not considered there and experimental values of the collisional scattering lengths for the two states. J. A. Coxon and P. Hajigeorgiou, J. Chem. Phys. 132, 09105 (2010). F. Xie et al. J. Chem. Phys. 130 051102 (2009). F. Xie et al. J. Chem. Phys. 135, 024303 (2011) J. G. Danzl et al., Science, 321, 1062 (2008). C. Chin, et al., Phys. Rev. Lett. 85, 2717 (2000) P. J. Leo, C. J. Williams, and P. S. Julienne, Phys. Rev. Lett. 85, 2721 (2000)

  20. No rescue for the no boundary proposal: Pointers to the future of quantum cosmology

    NASA Astrophysics Data System (ADS)

    Feldbrugge, Job; Lehners, Jean-Luc; Turok, Neil

    2018-01-01

    In recent work [J. Feldbrugge et al. Phys. Rev. D 95, 103508 (2017)., 10.1103/PhysRevD.95.103508 and J. Feldbrugge et al. Phys. Rev. Lett. 119, 171301 (2017)., 10.1103/PhysRevLett.119.171301], we introduced Picard-Lefschetz theory as a tool for defining the Lorentzian path integral for quantum gravity in a systematic semiclassical expansion. This formulation avoids several pitfalls occurring in the Euclidean approach. Our method provides, in particular, a more precise formulation of the Hartle-Hawking no boundary proposal, as a sum over real Lorentzian four-geometries interpolating between an initial three-geometry of zero size, i.e., a point, and a final three-geometry. With this definition, we calculated the no boundary amplitude for a closed universe with a cosmological constant, assuming cosmological symmetry for the background and including linear perturbations. We found the opposite semiclassical exponent to that obtained by Hartle and Hawking for the creation of a de Sitter spacetime "from nothing." Furthermore, we found the linearized perturbations to be governed by an inverse Gaussian distribution, meaning they are unsuppressed and out of control. Recently, Diaz Dorronsoro et al. [Phys. Rev. D 96, 043505 (2017), 10.1103/PhysRevD.96.043505] followed our methods but attempted to rescue the no boundary proposal by integrating the lapse over a different, intrinsically complex contour. Here, we show that, in addition to the desired Hartle-Hawking saddle point contribution, their contour yields extra, nonperturbative corrections which again render the perturbations unsuppressed. We prove there is no choice of complex contour for the lapse which avoids this problem. We extend our discussion to include backreaction in the leading semiclassical approximation, fully nonlinearly for the lowest tensor harmonic and to second order for all higher modes. Implications for quantum de Sitter spacetime and for cosmic inflation are briefly discussed.

  1. X-radiography, XRD and Ultrasonic Data Transfer Function Technique - Simultaneous Measurements Under Simulated Mantle Conditions in a Multi-Anvil Device

    NASA Astrophysics Data System (ADS)

    Mueller, H. J.; Schilling, F. R.; Lathe, C.

    2004-05-01

    consider the characteristics of the specific transducer-glue-anvil combination (Mueller et al., 2003). To collect the data for the following calculation of Vp and Vs requires just few seconds. The excitation function, applied to the transducer by an arbitrary waveform generator, is the result of the summation of all sinusoidal waves inside the frequency range. The response of the system - transducer - anvil - buffer rod - sample - reflector - for each of the frequencies can be reproduced by convoluting the resulting transfer function with these monochromatic waves step by step. Some recent results on the non-quenchable high-P - low-P clinoenstatite transition and to the quartz-coesite transition will be given to discuss the different interferometric techniques, including the XRD-data and X-radiography results, necessary to detect the phase transitions under in situ conditions and to measure the sample deformation. Li, B.; Vaughan, M.T.; Kung, J.; Weidner, D.J., NSLS Activity Report 2001, 2-103-106, (2001). Li, B.; Chen, K.; Kung, J.; Liebermann, R.C.; Weidner, D.J., J. Phys.: Condens. Matter 14, 11337-11342, (2002). Mueller, H.J.; Schilling, F.R.; Lauterjung, J.; Lathe, C., Eur. J. Mineral., 15, 865-873, (2003). Mueller, H.J.; Wunder, B.; Lathe, C.; Schilling, F.R.; Eur. J. Mineral., submitted, (2004).

  2. Comment on "Troublesome aspects of the Renyi-MaxEnt treatment"

    NASA Astrophysics Data System (ADS)

    Oikonomou, Thomas; Bagci, G. Baris

    2017-11-01

    Plastino et al. [Plastino et al., Phys. Rev. E 94, 012145 (2016), 10.1103/PhysRevE.94.012145] recently stated that the Rényi entropy is not suitable for thermodynamics by using functional calculus, since it leads to anomalous results unlike the Tsallis entropy. We first show that the Tsallis entropy also leads to such anomalous behaviors if one adopts the same functional calculus approach. Second, we note that one of the Lagrange multipliers is set in an ad hoc manner in the functional calculus approach of Plastino et al. Finally, the explanation for these anomalous behaviors is provided by observing that the generalized distributions obtained by Plastino et al. do not yield the ordinary canonical partition function in the appropriate limit and therefore cannot be considered as genuine generalized distributions.

  3. Thinshell symmetry surrogates for the National Ignition Facility: A rocket equation analysis

    NASA Astrophysics Data System (ADS)

    Amendt, Peter; Shestakov, A. I.; Landen, O. L.; Bradley, D. K.; Pollaine, S. M.; Suter, L. J.; Turner, R. E.

    2001-06-01

    Several techniques for inferring the degree of flux symmetry in indirectly driven cylindrical hohlraums have been developed over the past several years for eventual application to the National Ignition Facility (NIF) [Paisner et al., Laser Focus World 30, 75 (1994)]. These methods use various ignition capsule surrogates, including non-cryogenic imploded capsules [Hauer et al., Phys. Plasmas 2, 2488 (1995)], backlit aerogel foamballs [Amendt et al., Rev. Sci. Instrum. 66, 785 (1995)], reemission balls [Delamater, Magelssen, and Hauer, Phys. Rev. E 53, 5240 (1996)], and backlit thinshells [Pollaine et al., Phys. Plasmas 8, 2357 (2001)]. Recent attention has focussed on the backlit thinshells as a promising means for detecting higher-order Legendre flux asymmetries, e.g., P6 and P8, which are predicted to be important sources of target performance degradation on the NIF for levels greater than 1% [Haan et al., Phys. Plasmas 2, 2490 (1995)]. A key property of backlit thinshells is the strong amplification of modal flux asymmetry imprinting with shell convergence. A simple single-parameter analytic description based on a rocket model is presented which explores the degree of linearity of the shell response to an imposed flux asymmetry. Convergence and mass ablation effects introduce a modest level of nonlinearity in the shell response. The effect of target fabrication irregularities on shell distortion is assessed with the rocket model and particular sensitivity to shell thickness variations is shown. The model can be used to relate an observed or simulated backlit implosion trajectory to an ablation pressure asymmetry history. Ascertaining this history is an important element for readily establishing the degree of surrogacy of a symmetry target for a NIF ignition capsule.

  4. Device-independent secret-key-rate analysis for quantum repeaters

    NASA Astrophysics Data System (ADS)

    Holz, Timo; Kampermann, Hermann; Bruß, Dagmar

    2018-01-01

    The device-independent approach to quantum key distribution (QKD) aims to establish a secret key between two or more parties with untrusted devices, potentially under full control of a quantum adversary. The performance of a QKD protocol can be quantified by the secret key rate, which can be lower bounded via the violation of an appropriate Bell inequality in a setup with untrusted devices. We study secret key rates in the device-independent scenario for different quantum repeater setups and compare them to their device-dependent analogon. The quantum repeater setups under consideration are the original protocol by Briegel et al. [Phys. Rev. Lett. 81, 5932 (1998), 10.1103/PhysRevLett.81.5932] and the hybrid quantum repeater protocol by van Loock et al. [Phys. Rev. Lett. 96, 240501 (2006), 10.1103/PhysRevLett.96.240501]. For a given repeater scheme and a given QKD protocol, the secret key rate depends on a variety of parameters, such as the gate quality or the detector efficiency. We systematically analyze the impact of these parameters and suggest optimized strategies.

  5. A verification of the gyrokinetic microstability codes GEM, GYRO, and GS2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bravenec, R. V.; Chen, Y.; Wan, W.

    2013-10-15

    A previous publication [R. V. Bravenec et al., Phys. Plasmas 18, 122505 (2011)] presented favorable comparisons of linear frequencies and nonlinear fluxes from the Eulerian gyrokinetic codes gyro[J. Candy and R. E. Waltz, J. Comput. Phys. 186, 545 (2003)] and gs2[W. Dorland et al., Phys. Rev. Lett. 85, 5579 (2000)]. The motivation was to verify the codes, i.e., demonstrate that they correctly solve the gyrokinetic-Maxwell equations. The premise was that it is highly unlikely for both codes to yield the same incorrect results. In this work, we add the Lagrangian particle-in-cell code gem[Y. Chen and S. Parker, J. Comput. Phys.more » 220, 839 (2007)] to the comparisons, not simply to add another code, but also to demonstrate that the codes' algorithms do not matter. We find good agreement of gem with gyro and gs2 for the plasma conditions considered earlier, thus establishing confidence that the codes are verified and that ongoing validation efforts for these plasma parameters are warranted.« less

  6. Partial entropic stabilization of lattice Boltzmann magnetohydrodynamics

    NASA Astrophysics Data System (ADS)

    Flint, Christopher; Vahala, George

    2018-01-01

    The entropic lattice Boltzmann algorithm of Karlin et al. [Phys. Rev. E 90, 031302 (2014), 10.1103/PhysRevE.90.031302] is partially extended to magnetohydrodynamics, based on the Dellar model of introducing a vector distribution for the magnetic field. This entropic ansatz is now applied only to the scalar particle distribution function so as to permit the many problems entailing magnetic field reversal. A 9-bit lattice is employed for both particle and magnetic distributions for our two-dimensional simulations. The entropic ansatz is benchmarked against our earlier multiple relaxation lattice-Boltzmann model for the Kelvin-Helmholtz instability in a magnetized jet. Other two-dimensional simulations are performed and compared to results determined by more standard direct algorithms: in particular the switch over between the Kelvin-Helmholtz or tearing mode instability of Chen et al. [J. Geophys. Res.: Space Phys. 102, 151 (1997), 10.1029/96JA03144], and the generalized Orszag-Tang vortex model of Biskamp-Welter [Phys. Fluids B 1, 1964 (1989), 10.1063/1.859060]. Very good results are achieved.

  7. Kβ/ Kα intensity ratios for X-ray production in 3d metals by gamma-rays and protons

    NASA Astrophysics Data System (ADS)

    Bhuinya, C. R.; Padhi, H. C.

    1994-04-01

    Systematic measurements of Kβ/ Kα intensity ratios for X-ray production in 3d metals have been carried out using γ-ray and fast proton ionization methods. The measured ratios from proton ionization experiments indicate production of multivacancies in the L shell giving rise to higher Kβ/ Kα ratios compared to the present γRF results and 2 MeV proton ionization results of Perujo et al. [Perujo A., Maxwell J. A., Teesdale W. J. and Cambell J. L. (1987) J. Phys. B: Atom. Molec. Phys.20, 4973]. This is consistent with the SCA model calculation which gives increased simultaneous K- and L-shell ionization at 4 MeV. The present results from γRF experiments are in close agreement with the 2 MeV proton ionization results of Perujo et al. (1987) and also with the theoretical calculation of jankowski and Polasik [Jankowski K. and Polasik M. (1989) J. Phys. B: Atom. Molec. Optic. Phys. 22, 2369] but the theoretical results of Scofield [Scofield J. H. (1974a) Atom. Data Nucl. Data Tables14, 12] are somewhat higher.

  8. Isotonic similarities in isotope shifts from Hg to Ra.

    NASA Astrophysics Data System (ADS)

    Stroke, H. H.

    2003-04-01

    Isotope shifts (IS) in atomic spectra of heavy elements reflect largely the variation in of the nuclear charge distribution. Our early systematic measurements of IS for an extended range of stable and radioactive isotopes and nuclear isomers in Tl and Hg^1 showed that by displaying the relative IS, normalized to a chosen pair of isotopes, there was a striking similarity for the IS of isotones. This essentially divides out the electronic factor in the IS and allows the comparison of Δ for neighboring Z as N is varied. Following our further studies on Pb and Bi^2 and those on Fr at ISOLDE by the Orsay spectroscopy group^3, we found that the isotonic similarity extended to these elements. Since then, many additional measurements were made, principally at ISOLDE^4, extending to Ra the elements studied. The isotonic shift similarities persist from Z=80 to 88. We noted that the relative isotope and isomer shifts can be used to investigate the polarization of the nucleus by the added neutrons, a model used in a calculation by Barrett.^5 . The new data may serve further in this direction. ^1W,J.Tomlinson, H.H. Stroke, Nucl.Phys. 60, 614 (1964). ^2M. Barboza-Flores et al., Z.Phys. A 321, 85 (1985), ^3S. Liberman et al., Phys .Rev. A 22, 2732 (1980). ^4E,g. M.R. Pearson et al., J.Phys. G 26, 1829 (2000). ^5R.C. Barrett, Nucl. Phys. 88, 128 (1966).

  9. Ohmic contacts to Al-rich AlGaN heterostructures

    DOE PAGES

    Douglas, E. A.; Reza, S.; Sanchez, C.; ...

    2017-06-06

    Due to the ultra-wide bandgap of Al-rich AlGaN, up to 5.8 eV for the structures in this study, obtaining low resistance ohmic contacts is inherently difficult to achieve. A comparative study of three different fabrication schemes is presented for obtaining ohmic contacts to an Al-rich AlGaN channel. Schottky-like behavior was observed for several different planar metallization stacks (and anneal temperatures), in addition to a dry-etch recess metallization contact scheme on Al 0.85Ga 0.15N/Al 0.66Ga 0.34N. However, a dry etch recess followed by n +-GaN regrowth fabrication process is reported as a means to obtain lower contact resistivity ohmic contacts onmore » a Al 0.85Ga 0.15N/Al 0.66Ga 0.34N heterostructure. In conclusion, specific contact resistivity of 5×10 -3 Ω cm 2 was achieved after annealing Ti/Al/Ni/Au metallization.« less

  10. Growth and stress-induced transformation of zinc blende AlN layers in Al-AlN-TiN multilayers

    DOE PAGES

    Li, Nan; Yadav, Satyesh K.; Wang, Jian; ...

    2015-12-18

    We report that AlN nanolayers in sputter deposited {111}Al/AlN/TiN multilayers exhibit the metastable zinc-blende-structure (z-AlN). Based on density function theory calculations, the growth of the z-AlN is ascribed to the kinetically and energetically favored nitridation of the deposited aluminium layer. In situ nanoindentation of the as-deposited {111}Al/AlN/TiN multilayers in a high-resolution transmission electron microscope revealed the z-AlN to wurzite AlN phase transformation through collective glide of Shockley partial dislocations on every two {111} planes of the z-AlN.

  11. Measurement of second order susceptibilities of GaN and AlGaN

    NASA Astrophysics Data System (ADS)

    Sanford, N. A.; Davydov, A. V.; Tsvetkov, D. V.; Dmitriev, A. V.; Keller, S.; Mishra, U. K.; DenBaars, S. P.; Park, S. S.; Han, J. Y.; Molnar, R. J.

    2005-03-01

    Rotational Maker fringes, scaled with respect to χ11(2) of crystalline quartz, were used to determine the second order susceptibilities χ31(2) and χ33(2) for samples of thin AlxGa1-xN films, a thicker GaN film, and a free-standing GaN platelets. The pump wavelength was 1064nm. The AlxGa1-xN samples, ranging in thickness from roughly 0.5to4.4μm, were grown by metalorganic chemical vapor deposition (MOCVD) and hydride vapor-phase epitaxy (HVPE) on (0001) sapphire substrates. The Al mole fractions x were 0, 0.419, 0.507, 0.618, 0.660, and 0.666, for the MOCVD-grown samples, and x =0, 0.279, 0.363, and 0.593 for the HVPE-grown samples. An additional HVPE-grown GaN sample ˜70μm thick was also examined. The free-standing bulk GaN platelets consisted of an HVPE grown film ˜226μm thick removed from its growth substrate, and a crystal ˜160μm thick grown by high-pressure techniques. For the AlxGa1-xN samples, the magnitudes of χ31(2) and χ33(2) decrease roughly linearly with increasing x and extrapolate to ˜0 for x =1. Furthermore, the constraint expected for a perfect wurtzite structure, namely χ33(2)=-2χ31(2), was seldom observed, and the samples with x =0.660 and x =0.666 showed χ31(2) and χ33(2) having the same sign. These results are consistent with the theoretical studies of nonlinear susceptibilities for AlN and GaN performed by Chen et al. [Appl. Phys. Lett. 66, 1129 (1995)]. The thicker bulk GaN samples displayed a complex superposition of high- and low-frequency Maker fringes due to the multiple-pass interference of the pump and second-harmonic generation beams, and the nonlinear coefficients were approximately consistent with those measured for the thin-film GaN sample.

  12. Ir Spectroscopic Studies on Microsolvation of HCl by Water

    NASA Astrophysics Data System (ADS)

    Mani, Devendra; Schwan, Raffael; Fischer, Theo; Dey, Arghya; Kaufmann, Matin; Redlich, Britta; van der Meer, Lex; Schwaab, Gerhard; Havenith, Martina

    2016-06-01

    Acid dissociation reactions are at the heart of chemistry. These reactions are well understood at the macroscopic level. However, a microscopic level understanding is still in the early stages of development. Questions such as 'how many H_2O molecules are needed to dissociate one HCl molecule?' have been posed and explored both theoretically and experimentally.1-5 Most of the theoretical calculations predict that four H_2O molecules are sufficient to dissociate one HCl molecule, resulting in the formation of a solvent separated H_3O+(H_2O)3Cl- cluster.1-3 IR spectroscopy in helium nanodroplets has earlier been used to study this dissociation process.3-5 However, these studies were carried out in the region of O-H and H-Cl stretch, which is dominated by the spectral features of undissociated (HCl)m-(H_2O)n clusters. This contributed to the ambiguity in assigning the spectral features arising from the dissociated cluster.4,5 Recent predictions from Bowman's group, suggest the presence of a broad spectral feature (1300-1360 wn) for the H_3O+(H_2O)3Cl- cluster, corresponding to the umbrella motion of H_3O+ moiety.6 This region is expected to be free from the spectral features due to the undissociated clusters. In conjunction with the FELIX laboratory, we have performed experiments on the (HCl)m(H_2O)n (m=1-2, n≥4) clusters, aggregated in helium nanodroplets, in the 900-1700 wn region. Mass selective measurements on these clusters revealed the presence of a weak-broad feature which spans between 1000-1450 wn and depends on both HCl as well as H_2O concentration. Measurements are in progress for the different deuterated species. The details will be presented in the talk. References: 1) C.T. Lee et al., J. Chem. Phys., 104, 7081 (1996). 2) H. Forbert et al., J. Am. Chem. Soc., 133, 4062 (2011). 3) A. Gutberlet et al., Science, 324, 1545 (2009). 4) S. D. Flynn et al., J. Phys. Chem. Lett., 1, 2233 (2010). 5) M. Letzner et al., J. Chem. Phys., 139, 154304 (2013). 6) J. M

  13. Inverse modelling of radionuclide release rates using gamma dose rate observations

    NASA Astrophysics Data System (ADS)

    Hamburger, Thomas; Evangeliou, Nikolaos; Stohl, Andreas; von Haustein, Christoph; Thummerer, Severin; Wallner, Christian

    2015-04-01

    inversion method uses a Bayesian formulation considering uncertainties for the a priori source term and the observations (Eckhardt et al., 2008, Stohl et al., 2012). The a priori information on the source term is a first guess. The gamma dose rate observations are used to improve the first guess and to retrieve a reliable source term. The details of this method will be presented at the conference. This work is funded by the Bundesamt für Strahlenschutz BfS, Forschungsvorhaben 3612S60026. References Davoine, X. and Bocquet, M., Atmos. Chem. Phys., 7, 1549-1564, 2007. Devell, L., et al., OCDE/GD(96)12, 1995. Eckhardt, S., et al., Atmos. Chem. Phys., 8, 3881-3897, 2008. Saunier, O., et al., Atmos. Chem. Phys., 13, 11403-11421, 2013. Stohl, A., et al., Atmos. Environ., 32, 4245-4264, 1998. Stohl, A., et al., Atmos. Chem. Phys., 5, 2461-2474, 2005. Stohl, A., et al., Atmos. Chem. Phys., 12, 2313-2343, 2012.

  14. Simulation of Ionization Effects for High-Density Positron Drivers in future Plasma Wakefield Experiments

    NASA Astrophysics Data System (ADS)

    Dimitrov, D. A.; Bruhwiler, D. L.; Busby, R.; Cary, J. R.; Esarey, E.; Leemans, W.

    2003-10-01

    Recent particle-in-cell simulations have shown [1] that the self-fields of an electron beam driver in a plasma wakefield accelerator can tunnel ionize neutral Li, leading to plasma wake dynamics differing significantly from that of a preionized plasma. It has also been shown, for the case of a preionized plasma, that the plasma wake of a positron driver differs strongly [2] from that of an electron driver. We will present particle- in-cell simulations, using the OOPIC [3] code, showing the effects of tunneling ionization on the plasma wake generated by high-density electron and positron drivers. The results will be compared to previous work on electron drivers with tunneling ionization and positron drivers without ionization. Parameters relevant to the E-164 and E-164x experiments at SLAC will be considered. [1] D.L. Bruhwiler et al., Phys. Plasmas 10 (2003), p. 2022. [2] S. Lee et al., Phys. Rev. E 64, 045501(R) (2001). [3] D.L. Bruhwiler et al., Phys. Rev. ST-AB 4, 101302 (2001).

  15. Influence of nuclear basic data on the calculation of production cross sections of superheavy nuclei

    NASA Astrophysics Data System (ADS)

    Bao, X. J.; Gao, Y.; Li, J. Q.; Zhang, H. F.

    2015-07-01

    The center of the predicted island of stability of superheavy nuclei (SHN) has not yet been observed experimentally. Many theories are being developed to understand the synthesizing mechanism of superheavy nuclei. However, all of them have to use some basic nuclear data. Three data tables, FRDM1995 [P. Möller et al., At. Data Nucl. Data Tables 59, 185 (1995), 10.1006/adnd.1995.1002], KTUY2005 [H. Koura et al., Prog. Theor. Phys. 113, 305 (2005), 10.1143/PTP.113.305], and WS2010 [Ning Wang et al., Phys. Rev. C 82, 044304 (2010), 10.1103/PhysRevC.82.044304], are used to investigate the SHN production. Based on the dinuclear system concept, the evaporation residue cross sections of SHN for Z =112-118 are calculated for the 48Ca -induced hot fusion reactions. It turns out that unlike the predictions made with the KTUY2005 and WS2010 data, the magic numbers Z =114 and N =184 predicted with the FRDM1995 data do not contradict the experimental data obtained so far.

  16. Breathing Mode in Complex Plasmas

    NASA Astrophysics Data System (ADS)

    Fujioka, K.; Henning, C.; Ludwig, P.; Bonitz, M.; Melzer, A.; Vitkalov, S.

    2007-11-01

    The breathing mode is a fundamental normal mode present in Coulomb systems, and may have utility in identifying particle charge and the Debye length of certain systems. The question remains whether this mode can be extended to strongly coupled Yukawa balls [1]. These systems are characterized by particles confined within a parabolic potential well and interacting through a shielded Coulomb potential [2,3]. The breathing modes for a variety of systems in 1, 2, and 3 dimensions are computed by solving the eigenvalue problem given by the dynamical (Hesse) matrix. These results are compared to theoretical investigations that assume a strict definition for a breathing mode within the system, and an analysis is made of the most fitting model to utilize in the study of particular systems of complex plasmas [1,4]. References [1] T.E. Sheridan, Phys. of Plasmas. 13, 022106 (2006)[2] C. Henning et al., Phys. Rev. E 74, 056403 (2006)[3] M. Bonitz et al., Phys. Rev. Lett. 96, 075001 (2006)[4] C. Henning et al., submitted for publication

  17. Reliability of III-V electronic devices -- the defects that cause the trouble

    NASA Astrophysics Data System (ADS)

    Pantelides, Sokrates T.

    2012-02-01

    Degradation of electronic devices by hot electrons is universally attributed to the generation of defects, but the mechanisms for defect generation and the specific nature of the pertinent defects are not known for most systems. Here we describe three recent case studies [1] in III-V high-electron-mobility transistors that illustrate the power of combining density functional calculations and experimental data to identify the pertinent defects and associated degradation mechanisms. In all cases, benign pre-existing defects are either depassivated (irreversible degradation) or transformed to a metastable state (reversible degradation). This work was done in collaboration with R.D. Schrimpf, D.M. Fleetwood, Y. Puzyrev, X. Shen, T. Roy, S. DasGupta, and B.R. Tuttle. Devices were provided by D.F. Brown, J. Speck and U. Mishra, and by J. Bergman and B. Brar. [4pt] [1] Y. S. Puzyrev et al., Appl. Phys. Lett. 96, 053505 (2010); T. Roy et al., Appl. Phys. Lett. 96, 133503 (2010); X. Shen et al., J. Appl. Phys. 108, 114505 (2010).

  18. Direct observation of bulk Fermi surface at higher Brillouin zones in a heavily hole-doped cuprate

    NASA Astrophysics Data System (ADS)

    Al-Sawai, W.; Sakurai, Y.; Itou, M.; Barbiellini, B.; Mijnarends, P. E.; Markiewicz, R. S.; Kaprzyk, S.; Gillet, J.-M.; Wakimoto, S.; Fujita, M.; Basak, S.; Lin, H.; Bansil, A.; Yamada, K.

    2010-03-01

    We have observed the bulk Fermi surface (FS) in an overdoped (x=0.3) single crystal of La2-xSrxCuO4 by using Compton scattering. A 2-D momentum density reconstruction [1] from measured Compton profiles, yields a clear FS signature in a higher Brillouin zone centered at p=(1.5,1.5) a.u. The quantitative agreement with density functional theory (DFT) calculations [2] and momentum density experiment suggests that Fermi-liquid physics is restored in the overdoped regime. We have also measured the 2-D angular correlation of positron annihilation radiation (2D-ACAR) [3] and noticed a similar quantitative agreement with the DFT simulations. However, 2D-ACAR does not give a clear signature of the FS in the extended momentum space in both theory and experiment. Work supported in part by the US DOE.[1] Y. Tanaka et al., Phys. Rev. B 63, 045120 (2001).[2] S. Sahrakorpi et al., Phys. Rev. Lett. 95, 157601 (2005).[3] L. C. Smedskjaer et al., J. Phys. Chem. Solids 52, 1541 (1991).

  19. Revealing electronic structure changes in Chevrel phase cathodes upon Mg insertion using X-ray absorption spectroscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wan, Liwen F.; Wright, Joshua; Perdue, Brian R.

    Following previous work predicting the electronic response of the Chevrel phase Mo6S8 upon Mg insertion (Thole et al., Phys. Chem. Chem. Phys., 2015, 17, 22548), we provide the experimental proof, evident in X-ray absorption spectroscopy, to illustrate the charge compensation mechanism of the Chevrel phase compound during Mg insertion and de-insertion processes.

  20. Properties of the State of the Art of Bulk III-V Nitride Substrates and Homoepitaxial Layers

    DTIC Science & Technology

    2010-01-01

    Bockowski M, Kamler G, Litwin -Staszewska E and Porowski S 2005 J. Cryst. Growth 281 38 [69] Grzegory I, Lucznik B, Bockowski M, Pastuszka B, Kamler G...and Han J Y 2002 Phys. Rev. B 66 233311 [106] Litwin -Staszewska E et al 1999 Phys. Status Solidi b 216 567 [107] Freitas J A Jr, Gowda M, Tischler J