Observation of isoscalar and isovector dipole excitations in neutron-rich 20O

NASA Astrophysics Data System (ADS)

Nakatsuka, N.; Baba, H.; Aumann, T.; Avigo, R.; Banerjee, S. R.; Bracco, A.; Caesar, C.; Camera, F.; Ceruti, S.; Chen, S.; Derya, V.; Doornenbal, P.; Giaz, A.; Horvat, A.; Ieki, K.; Inakura, T.; Imai, N.; Kawabata, T.; Kobayashi, N.; Kondo, Y.; Koyama, S.; Kurata-Nishimura, M.; Masuoka, S.; Matsushita, M.; Michimasa, S.; Million, B.; Motobayashi, T.; Murakami, T.; Nakamura, T.; Ohnishi, T.; Ong, H. J.; Ota, S.; Otsu, H.; Ozaki, T.; Saito, A.; Sakurai, H.; Scheit, H.; Schindler, F.; Schrock, P.; Shiga, Y.; Shikata, M.; Shimoura, S.; Steppenbeck, D.; Sumikama, T.; Syndikus, I.; Takeda, H.; Takeuchi, S.; Tamii, A.; Taniuchi, R.; Togano, Y.; Tscheuschner, J.; Tsubota, J.; Wang, H.; Wieland, O.; Wimmer, K.; Yamaguchi, Y.; Yoneda, K.; Zenihiro, J.

2017-05-01

The isospin characters of low-energy dipole excitations in neutron-rich unstable nucleus 20O were investigated, for the first time in unstable nuclei. Two spectra obtained from a dominant isovector probe (20O + Au) and a dominant isoscalar probe (20O + α) were compared and analyzed by the distorted-wave Born approximation to extract independently the isovector and isoscalar dipole strengths. Two known 1- states with large isovector dipole strengths at energies of 5.36(5) MeV (11-) and 6.84(7) MeV (12-) were also excited by the isoscalar probe. These two states were found to have different isoscalar dipole strengths, 2.70(32)% (11-) and 0.67(12)% (12-), respectively, in exhaustion of the isoscalar dipole-energy-weighted sum rule. The difference in isoscalar strength indicated that they have different underlying structures.

Breaking of axial symmetry in excited heavy nuclei as identified in giant dipole resonance data

DOE PAGES

Grosse, E.; Junghans, A. R.; Massarczyk, R.

2017-11-28

Here, a recent theoretical prediction of a breaking of axial symmetry in quasi all heavy nuclei is confronted to a new critical analysis of photon strength functions of nuclei in the valley of stability. For the photon strength in the isovector giant dipole resonance (IVGDR) regime a parameterization of GDR shapes by the sum of three Lorentzians (TLO) is extrapolated to energies below and above the IVGDR. The impact of non-GDR modes adding to the low energy slope of photon strength is discussed including recent data on photon scattering and other radiative processes. These are shown to be concentrated inmore » energy regions where various model calculations predict intermediate collective strength; thus they are obviously separate from the IVGDR tail. The triple Lorentzian (TLO) ansatz for giant dipole resonances is normalized in accordance to the dipole sum rule. The nuclear droplet model with surface dissipation accounts well for positions and widths without local, nuclide specific, parameters. Very few and only global parameters are needed when a breaking of axial symmetry already in the valley of stability is admitted and hence a reliable prediction for electric dipole strength functions also outside of it is expected.« less

Breaking of axial symmetry in excited heavy nuclei as identified in giant dipole resonance data

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

Grosse, E.; Junghans, A. R.; Massarczyk, R.

Here, a recent theoretical prediction of a breaking of axial symmetry in quasi all heavy nuclei is confronted to a new critical analysis of photon strength functions of nuclei in the valley of stability. For the photon strength in the isovector giant dipole resonance (IVGDR) regime a parameterization of GDR shapes by the sum of three Lorentzians (TLO) is extrapolated to energies below and above the IVGDR. The impact of non-GDR modes adding to the low energy slope of photon strength is discussed including recent data on photon scattering and other radiative processes. These are shown to be concentrated inmore » energy regions where various model calculations predict intermediate collective strength; thus they are obviously separate from the IVGDR tail. The triple Lorentzian (TLO) ansatz for giant dipole resonances is normalized in accordance to the dipole sum rule. The nuclear droplet model with surface dissipation accounts well for positions and widths without local, nuclide specific, parameters. Very few and only global parameters are needed when a breaking of axial symmetry already in the valley of stability is admitted and hence a reliable prediction for electric dipole strength functions also outside of it is expected.« less

Isovector and isoscalar dipole excitations in 9Be and 10Be studied with antisymmetrized molecular dynamics

NASA Astrophysics Data System (ADS)

Kanada-En'yo, Yoshiko

2016-02-01

Isovector and isoscalar dipole excitations in 9Be and 10Be are investigated in the framework of antisymmetrized molecular dynamics, in which angular-momentum and parity projections are performed. In the present method, 1p-1h excitation modes built on the ground state and a large amplitude α -cluster mode are taken into account. The isovector giant dipole resonance (GDR) in E >20 MeV shows the two-peak structure, which is understood from the dipole excitation in the 2 α core part with the prolate deformation. Because of valence neutron modes against the 2 α core, low-energy E 1 resonances appear in E <20 MeV, exhausting about 20 % of the Thomas-Reiche-Kuhn sum rule and 10 % of the calculated energy-weighted sum. The dipole resonance at E ˜15 MeV in 10Be can be interpreted as the parity partner of the ground state having a 6He+α structure and has remarkable E 1 strength because of the coherent contribution of two valence neutrons. The isoscalar dipole strength for some low-energy resonances is significantly enhanced by the coupling with the α -cluster mode. For the E 1 strength of 9Be, the calculation overestimates the energy-weighted sum (EWS) in the low-energy (E <20 MeV) and GDR (20

Dipole Excitation of Soft and Giant Resonances in 132Sn and neighboring unstable nuclei

NASA Astrophysics Data System (ADS)

Boretzky, Konstanze

2006-04-01

The evolution of dipole-strength distributions above the one-neutron threshold was investigated for exotic neutron-rich nuclei in a series of experiments using the electromagnetic projectile excitation at beam energies around 500 MeV/u. For halo nuclei, the large observed dipole strength (shown here for 11Be) is explained within the direct-breakup model to be of non-collective character. For neutron-rich oxygen isotopes, the origin of the observed low-lying strength is concluded to be due to single-particle transitions on theoretical grounds. The dipole strength spectra for 130,132Sn exhibit resonance-like structures observed at energies around 10 MeV exhausting a few percent of the Thomas-Reiche-Kuhn (TRK) sum rule, separated clearly from the dominant Giant Dipole Resonance (GDR). The data agree with predictions for a new dipole mode related to the oscillation of excess neutrons versus the core nucleons ("pygmy resonance").

Low-lying dipole modes in 26,28Ne in the quasiparticle relativistic random phase approximation

NASA Astrophysics Data System (ADS)

Cao, Li-Gang; Ma, Zhong-Yu

2005-03-01

The low-lying isovector dipole strengths in the neutron-rich nuclei 26Ne and 28Ne are investigated in the quasiparticle relativistic random phase approximation. Nuclear ground-state properties are calculated in an extended relativistic mean field theory plus Bardeen-Cooper-Schrieffer (BCS) method where the contribution of the resonant continuum to pairing correlations is properly treated. Numerical calculations are tested in the case of isovector dipole and isoscalar quadrupole modes in the neutron-rich nucleus 22O. It is found that in the present calculation, low-lying isovector dipole strengths at Ex<10MeV in nuclei 26Ne and 26Ne exhaust about 4.9% and 5.8% of the Thomas-Reiche-Kuhn dipole sum rule, respectively. The centroid energy of the low-lying dipole excitation is located at 8.3 MeV in 26Ne and 7.9 MeV in 28Ne.

Pygmy dipole mode in deformed neutron-rich Mg isotopes close to the drip line

NASA Astrophysics Data System (ADS)

Yoshida, Kenichi

2009-10-01

We investigate the microscopic structure of the low-lying isovector-dipole excitation mode in neutron-rich Mg36,38,40 close to the drip line by means of the deformed quasiparticle random-phase approximation employing the Skyrme and the local pairing energy-density functionals. It is found that the low-lying bump structure above the neutron emission-threshold energy develops when the drip line is approached, and that the isovector dipole strength at Ex<10 MeV exhausts about 6.0% of the classical Thomas-Reiche-Kuhn dipole sum rule in Mg40. We obtained the collective dipole modes at around 8-10 MeV in Mg isotopes, that consist of many two-quasiparticle excitations of the neutron. The transition density clearly shows an oscillation of the neutron skin against the isoscalar core. We found significant coupling effects between the dipole and octupole excitation modes due to the nuclear deformation. It is also found that the responses for the compressional dipole and isoscalar octupole excitations are much enhanced in the lower energy region.

The consequences of improperly describing oscillator strengths beyond the electric dipole approximation

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

Lestrange, Patrick J.; Egidi, Franco; Li, Xiaosong, E-mail: xsli@uw.edu

2015-12-21

The interaction between a quantum mechanical system and plane wave light is usually modeled within the electric dipole approximation. This assumes that the intensity of the incident field is constant over the length of the system and transition probabilities are described in terms of the electric dipole transition moment. For short wavelength spectroscopies, such as X-ray absorption, the electric dipole approximation often breaks down. Higher order multipoles are then included to describe transition probabilities. The square of the magnetic dipole and electric quadrupole are often included, but this results in an origin-dependent expression for the oscillator strength. The oscillator strengthmore » can be made origin-independent if all terms through the same order in the wave vector are retained. We will show the consequences and potential pitfalls of using either of these two expressions. It is shown that the origin-dependent expression may violate the Thomas-Reiche-Kuhn sum rule and the origin-independent expression can result in negative transition probabilities.« less

The consequences of improperly describing oscillator strengths beyond the electric dipole approximation.

PubMed

Lestrange, Patrick J; Egidi, Franco; Li, Xiaosong

2015-12-21

The interaction between a quantum mechanical system and plane wave light is usually modeled within the electric dipole approximation. This assumes that the intensity of the incident field is constant over the length of the system and transition probabilities are described in terms of the electric dipole transition moment. For short wavelength spectroscopies, such as X-ray absorption, the electric dipole approximation often breaks down. Higher order multipoles are then included to describe transition probabilities. The square of the magnetic dipole and electric quadrupole are often included, but this results in an origin-dependent expression for the oscillator strength. The oscillator strength can be made origin-independent if all terms through the same order in the wave vector are retained. We will show the consequences and potential pitfalls of using either of these two expressions. It is shown that the origin-dependent expression may violate the Thomas-Reiche-Kuhn sum rule and the origin-independent expression can result in negative transition probabilities.

The consequences of improperly describing oscillator strengths beyond the electric dipole approximation

NASA Astrophysics Data System (ADS)

Lestrange, Patrick J.; Egidi, Franco; Li, Xiaosong

2015-12-01

The interaction between a quantum mechanical system and plane wave light is usually modeled within the electric dipole approximation. This assumes that the intensity of the incident field is constant over the length of the system and transition probabilities are described in terms of the electric dipole transition moment. For short wavelength spectroscopies, such as X-ray absorption, the electric dipole approximation often breaks down. Higher order multipoles are then included to describe transition probabilities. The square of the magnetic dipole and electric quadrupole are often included, but this results in an origin-dependent expression for the oscillator strength. The oscillator strength can be made origin-independent if all terms through the same order in the wave vector are retained. We will show the consequences and potential pitfalls of using either of these two expressions. It is shown that the origin-dependent expression may violate the Thomas-Reiche-Kuhn sum rule and the origin-independent expression can result in negative transition probabilities.

Gigantic transverse x-ray magnetic circular dichroism in ultrathin Co in Au/Co/Au(001)

NASA Astrophysics Data System (ADS)

Koide, T.; Mamiya, K.; Asakura, D.; Osatune, Y.; Fujimori, A.; Suzuki, Y.; Katayama, T.; Yuasa, S.

2014-04-01

Transverse-geometry x-ray magnetic circular dichroism (TXMCD) measurements on Au/Co-staircase/Au(001) reveal the orbital origin of intrinsic in-plane magnetic anisotropy A gigantic TXMCD was successfully observed at the Co L3,2 edges for Co thickness (tC0) in the 2-monolayer regime. A TXMCD-sum-rule analysis shows a remarkable enhancement of an orbital-moment anisotropy (Δmorb) and of an in-plane magnetic dipole moment (m||T). Both Δmorb and m||T exhibit close similarity in tCo dependence, reflecting the in-plane magnetic anisotropy These observations evidence that extremely strong, intrinsic, in-plane magnetic anisotropy originates from the anisotropic orbital part of the wave function, dominating the dipole-dipole-interaction-derived, extrinsic, in-plane magnetic anisotropy.

Low-lying dipole resonance in neutron-rich Ne isotopes

NASA Astrophysics Data System (ADS)

Yoshida, Kenichi; van Giai, Nguyen

2008-07-01

Microscopic structure of the low-lying isovector dipole excitation mode in neutron-rich Ne26,28,30 is investigated by performing deformed quasiparticle-random-phase-approximation (QRPA) calculations. The particle-hole residual interaction is derived from a Skyrme force through a Landau-Migdal approximation. We obtain the low-lying resonance in Ne26 at around 8.6 MeV. It is found that the isovector dipole strength at Ex<10 MeV exhausts about 6.0% of the classical Thomas-Reiche-Kuhn dipole sum rule. This excitation mode is composed of several QRPA eigenmodes, one is generated by a ν(2s1/2-12p3/2) transition dominantly and the other mostly by a ν(2s1/2-12p1/2) transition. The neutron excitations take place outside of the nuclear surface reflecting the spatially extended structure of the 2s1/2 wave function. In Ne30, the deformation splitting of the giant resonance is large, and the low-lying resonance overlaps with the giant resonance.

Photoresponse of 60Ni below 10-MeV excitation energy: Evolution of dipole resonances in fp-shell nuclei near N=Z

NASA Astrophysics Data System (ADS)

Scheck, M.; Ponomarev, V. Yu.; Fritzsche, M.; Joubert, J.; Aumann, T.; Beller, J.; Isaak, J.; Kelley, J. H.; Kwan, E.; Pietralla, N.; Raut, R.; Romig, C.; Rusev, G.; Savran, D.; Schorrenberger, L.; Sonnabend, K.; Tonchev, A. P.; Tornow, W.; Weller, H. R.; Zilges, A.; Zweidinger, M.

2013-10-01

Background: Within the last decade, below the giant dipole resonance the existence of a concentration of additional electric dipole strength has been established. This accumulation of low-lying E1 strength is commonly referred to as pygmy dipole resonance (PDR).Purpose: The photoresponse of 60Ni has been investigated experimentally and theoretically to test the evolution of the PDR in a nucleus with only a small neutron excess. Furthermore, the isoscalar and isovector M1 resonances were investigated.Method: Spin-1 states were excited by exploiting the (γ,γ') nuclear resonance fluorescence technique with unpolarized continuous bremsstrahlung as well as with fully linearly polarized, quasimonochromatic, Compton-backscattered laser photons in the entrance channel of the reaction.Results: Up to 10 MeV a detailed picture of J=1 levels was obtained. For the preponderant number of the individual levels spin and parity were firmly assigned. Furthermore, branching ratios, transition widths, and reduced B(E1) or B(M1) excitation probability were calculated from the measured scattering cross sections. A comparison with theoretical results obtained within the quasiparticle phonon model allows an insight into the microscopic structure of the observed states.Conclusions: Below 10 MeV the directly observed E1 strength [∑B(E1)↑=(153.8±9.5) e2(fm)2] exhausts 0.5% of the Thomas-Reiche-Kuhn sum rule. This value increases to 0.8% of the sum rule [∑B(E1)↑=(250.9±31.1) e2(fm)2] when indirectly observed branches to lower-lying levels are considered. Two accumulations of M1 excited spin-1 states near 8 and 9 MeV excitation energy are identified as isoscalar and isovector M1 resonances dominated by proton and neutron f7/2→f5/2 spin-flip excitations. The B(M1)↑ strength of these structures accumulates to 3.94(27)μN2.

Correlations and sum rules in a half-space for a quantum two-dimensional one-component plasma

NASA Astrophysics Data System (ADS)

Jancovici, B.; Šamaj, L.

2007-05-01

This paper is the continuation of a previous one (Šamaj and Jancovici, 2007 J. Stat. Mech. P02002); for a nearly classical quantum fluid in a half-space bounded by a plain plane hard wall (no image forces), we had generalized the Wigner Kirkwood expansion of the equilibrium statistical quantities in powers of Planck's constant \\hbar . As a model system for a more detailed study, we consider the quantum two-dimensional one-component plasma: a system of charged particles of one species, interacting through the logarithmic Coulomb potential in two dimensions, in a uniformly charged background of opposite sign, such that the total charge vanishes. The corresponding classical system is exactly solvable in a variety of geometries, including the present one of a half-plane, when βe2 = 2, where β is the inverse temperature and e is the charge of a particle: all the classical n-body densities are known. In the present paper, we have calculated the expansions of the quantum density profile and truncated two-body density up to order \\hbar ^2 (instead of only to order \\hbar as in the previous paper). These expansions involve the classical n-body densities up to n = 4; thus we obtain exact expressions for these quantum expansions in this special case. For the quantum one-component plasma, two sum rules involving the truncated two-body density (and, for one of them, the density profile) have been derived, a long time ago, by using heuristic macroscopic arguments: one sum rule concerns the asymptotic form along the wall of the truncated two-body density; the other one concerns the dipole moment of the structure factor. In the two-dimensional case at βe2 = 2, we now have explicit expressions up to order \\hbar^2 for these two quantum densities; thus we can microscopically check the sum rules at this order. The checks are positive, reinforcing the idea that the sum rules are correct.

QRPA plus phonon coupling model and the photoabsorption cross section for 18,20,22O

NASA Astrophysics Data System (ADS)

Colò, G.; Bortignon, P. F.

2001-12-01

We have calculated the electric dipole strength distributions in the unstable neutron-rich oxygen isotopes 18,20,22O, in a model which include up to four quasiparticle-type configurations. The model is the extension, to include the effect of the pairing correlations, of a previous model very successful around closed shell nuclei, and it is based on the quasiparticle-phonon coupling. Low-lying dipole strength is found, which exhausts between 5 and 10% of the Thomas-Reiche-Kuhn (TRK) energy-weighted sum rule (EWSR) below 15 MeV excitation energy, in rather good agreement with recent experimental data. The role of the phonon coupling is shown to be crucial in order to obtain this result.

Halo-induced large enhancement of soft dipole excitation of 11Li observed via proton inelastic scattering

NASA Astrophysics Data System (ADS)

Tanaka, J.; Kanungo, R.; Alcorta, M.; Aoi, N.; Bidaman, H.; Burbadge, C.; Christian, G.; Cruz, S.; Davids, B.; Diaz Varela, A.; Even, J.; Hackman, G.; Harakeh, M. N.; Henderson, J.; Ishimoto, S.; Kaur, S.; Keefe, M.; Krücken, R.; Leach, K. G.; Lighthall, J.; Padilla Rodal, E.; Randhawa, J. S.; Ruotsalainen, P.; Sanetullaev, A.; Smith, J. K.; Workman, O.; Tanihata, I.

2017-11-01

Proton inelastic scattering off a neutron halo nucleus, 11Li, has been studied in inverse kinematics at the IRIS facility at TRIUMF. The aim was to establish a soft dipole resonance and to obtain its dipole strength. Using a high quality 66 MeV 11Li beam, a strongly populated excited state in 11Li was observed at Ex = 0.80 ± 0.02 MeV with a width of Γ = 1.15 ± 0.06 MeV. A DWBA (distorted-wave Born approximation) analysis of the measured differential cross section with isoscalar macroscopic form factors leads us to conclude that this observed state is excited in an electric dipole (E1) transition. Under the assumption of isoscalar E1 transitions, the strength is evaluated to be extremely large amounting to 30 ∼ 296 Weisskopf units, exhausting 2.2% ∼ 21% of the isoscalar E1 energy-weighted sum rule (EWSR) value. The large observed strength originates from the halo and is consistent with the simple di-neutron model of 11Li halo.

Alpha-like resonances in nuclei

NASA Astrophysics Data System (ADS)

Baran, V. V.; Delion, D. S.

2018-03-01

We investigate normal dipole oscillations in a system of protons, neutrons and α-particles within the Brink approach. We introduce an effective mass of α-clusters in terms of the spectroscopic factor. The Pauli exclusion principle is taken into account by using the Wildermuth rule. The ratio between alpha and giant resonance energy weighted sum rule (EWSR) is investigated for N = Z and N> Z systems. In both cases we notice an unexpected decrease of this ratio versus the increase of the spectroscopic factor. Due to this fact the possibility to experimentally detect α-like oscillations is enhanced in nuclei above 100Sn. The occurrence of the pygmy mode in N> Z systems decreases the EWSR for the α-like oscillations.

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.

Empirically constructed dynamic electric dipole polarizability function of magnesium and its applications

NASA Astrophysics Data System (ADS)

Babb, James F.

2015-08-01

The dynamic electric dipole polarizability function for the magnesium atom is formed by assembling the atomic electric dipole oscillator strength distribution from combinations of theoretical and experimental data for resonance oscillator strengths and for photoionization cross sections of valence and inner shell electrons. Consistency with the oscillator strength (Thomas-Reiche-Kuhn) sum rule requires the adopted principal resonance line oscillator strength to be several percent lower than the values given in two critical tabulations, though the value adopted is consistent with a number of theoretical determinations. The static polarizability is evaluated. Comparing the resulting dynamic polarizability as a function of the photon energy with more elaborate calculations reveals the contributions of inner shell electron excitations. The present results are applied to calculate the long-range interactions between two and three magnesium atoms and the interaction between a magnesium atom and a perfectly conducting metallic plate. Extensive comparisons of prior results for the principal resonance line oscillator strength, for the static polarizability, and for the van der Waals coefficient are given in the Appendix.

Theoretical evaluation of the radiative lifetimes of LiCs and NaCs in the A1Σ+ state

NASA Astrophysics Data System (ADS)

Mabrouk, N.; Berriche, H.

2017-08-01

Calculations of the adiabatic potential energy curves and the transition dipole moments between the ground (A1Σ+) and the first excited (A1Σ+) states have been determined for the LiCs and NaCs molecules. The calculations are performed using an ab initio approach based on non-empirical pseudopotentials for Cs+, Li+ and Na+ cores, parameterized l-dependent polarization potentials and full configuration interaction calculations. The potential energy curves and the transition dipole moment are used to estimate the radiative lifetimes of the vibrational levels of the A+Σ+ state using the Franck-Condon (FC) approximation and the approximate sum rule method. The radiative lifetimes associated with the A+Σ+ state are presented here for the first time. These data can help experimentalists to optimize photoassociative formation of ultracold molecules and their longevity in a trap or in an optical lattice.

Dipole response of neutron-rich Sn isotopes

NASA Astrophysics Data System (ADS)

Klimkiewicz, A.; Adrich, P.; Boretzky, K.; Fallot, M.; Aumann, T.; Cortina-Gil, D.; Datta Pramanik, U.; Elze, Th. W.; Emling, H.; Geissel, H.; Hellstroem, M.; Jones, K. L.; Kratz, J. V.; Kulessa, R.; Leifels, Y.; Nociforo, C.; Palit, R.; Simon, H.; Surowka, G.; Sümmerer, K.; Typel, S.; Walus, W.

2007-05-01

The neutron-rich isotopes 129-133Sn were studied in a Coulomb excitation experiment at about 500 AMeV using the FRS-LAND setup at GSI. From the exclusive measurement of all projectile-like particles following the excitation and decay of the projectile in a high-Z target, the energy differential cross section can be extracted. At these beam energies dipole transitions are dominating, and within the semi-classical approach the Coulomb excitation cross sections can be transformed into photoabsorption cross sections. In contrast to stable Sn nuclei, a substantial fraction of dipole strength is observed at energies below the giant dipole resonance (GDR). For 130Sn and 132Sn this strength is located in a peak-like structure around 10 MeV excitation energy and exhibits a few percent of the Thomas-Reiche Kuhn (TRK) sum-rule strength. Several calculations predict the appearance of dipole strength at low excitation energies in neutron-rich nuclei. This low-lying strength is often referred to as pygmy dipole resonance (PDR) and, in a macroscopic picture, is discussed in terms of a collective oscillation of excess neutrons versus the core nucleons. Moreover, a sharp rise is observed at the neutron separation threshold around 5 MeV for the odd isotopes. A possible contribution of 'threshold strength', which can be described within the direct-breakup model is discussed. The results for the neutron-rich Sn isotopes are confronted with results on stable nuclei investigated in experiments using real photons.

Separation of Pygmy Dipole and M1 Resonances in Zr90 by a High-Resolution Inelastic Proton Scattering Near 0°

NASA Astrophysics Data System (ADS)

Iwamoto, C.; Utsunomiya, H.; Tamii, A.; Akimune, H.; Nakada, H.; Shima, T.; Yamagata, T.; Kawabata, T.; Fujita, Y.; Matsubara, H.; Shimbara, Y.; Nagashima, M.; Suzuki, T.; Fujita, H.; Sakuda, M.; Mori, T.; Izumi, T.; Okamoto, A.; Kondo, T.; Bilgier, B.; Kozer, H. C.; Lui, Y.-W.; Hatanaka, K.

2012-06-01

A high-resolution measurement of inelastic proton scattering off Zr90 near 0° was performed at 295 MeV with a focus on a pronounced strength previously reported in the low-energy tail of giant dipole resonance. A forest of fine structure was observed in the excitation energy region 7-12 MeV. A multipole decomposition analysis of the angular distribution for the forest was carried out using the ECIS95 distorted-wave Born approximation code with the Hartree-Fock plus random-phase approximation model of E1 and M1 transition densities and inclusion of E1 Coulomb excitation. The analysis separated pygmy dipole and M1 resonances in the forest at EPDR=9.15±0.18MeV with ΓPDR=2.91±0.64MeV and at EM1=9.53±0.06MeV with ΓM1=2.70±0.17MeV in the Lorentzian function, respectively. The B(E1)↑ value for pygmy dipole resonance over 7-11 MeV is 0.75±0.08e2fm2, which corresponds to 2.1±0.2% of the Thomas-Reiche-Kuhn sum rule.

Thomas-Reiche-Khun populations in X-CH 3 and X-C 2H 5 series of molecules

NASA Astrophysics Data System (ADS)

Zitto, M. E.; Caputo, M. C.; Ferraro, M. B.; Lazzeretti, P.

2000-09-01

Calculations of nuclear electric shieldings, equivalent to dipole moment geometric derivatives, and related to atomic polar tensors, are presented for X-CH 3 and X-C 2H 5 molecules with X=NH 2, OH and F. The electric shielding tensors satisfy a constraint for the electrostatic equilibrium, i.e., the mixed length-acceleration Thomas-Reiche-Khun sum rule, which gives important indications on the reliability of theoretical predictions of IR intensities and leads to the definition of atomic populations. Numerical evidence was found for the additivity and transferability of atomic populations, within the X-substituted alkane series.

New QCD sum rules based on canonical commutation relations

NASA Astrophysics Data System (ADS)

Hayata, Tomoya

2012-04-01

New derivation of QCD sum rules by canonical commutators is developed. It is the simple and straightforward generalization of Thomas-Reiche-Kuhn sum rule on the basis of Kugo-Ojima operator formalism of a non-abelian gauge theory and a suitable subtraction of UV divergences. By applying the method to the vector and axial vector current in QCD, the exact Weinberg’s sum rules are examined. Vector current sum rules and new fractional power sum rules are also discussed.

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

Effect of broken axial symmetry on the electric dipole strength and the collective enhancement of level densities in heavy nuclei

NASA Astrophysics Data System (ADS)

Grosse, E.; Junghans, A. R.; Wilson, J. N.

2017-11-01

The basic parameters for calculations of radiative neutron capture, photon strength functions and nuclear level densities near the neutron separation energy are determined based on experimental data without an ad hoc assumption about axial symmetry—at variance to previous analysis. Surprisingly few global fit parameters are needed in addition to information on nuclear deformation, taken from Hartree Fock Bogolyubov calculations with the Gogny force, and the generator coordinator method assures properly defined angular momentum. For a large number of nuclei the GDR shapes and the photon strength are described by the sum of three Lorentzians, extrapolated to low energies and normalised in accordance to the dipole sum rule. Level densities are influenced strongly by the significant collective enhancement based on the breaking of shape symmetry. The replacement of axial symmetry by the less stringent requirement of invariance against rotation by 180° leads to a novel prediction for radiative neutron capture. It compares well to recent compilations of average radiative widths and Maxwellian average cross sections for neutron capture by even target nuclei. An extension to higher spin promises a reliable prediction for various compound nuclear reactions also outside the valley of stability. Such predictions are of high importance for future nuclear energy systems and waste transmutation as well as for the understanding of the cosmic synthesis of heavy elements.

A cluster version of the GGT sum rule

NASA Astrophysics Data System (ADS)

Hencken, Kai; Baur, Gerhard; Trautmann, Dirk

2004-03-01

We discuss the derivation of a "cluster sum rule" from the Gellmann-Goldberger-Thirring (GGT) sum rule as an alternative to the Thomas-Reiche-Kuhn (TRK) sum rule, which was used as the basis up to now. We compare differences in the assumptions and approximations. Some applications of the sum rule for halo nuclei, as well as, nuclei with a pronounced cluster structure are discussed.

Range of validity for perturbative treatments of relativistic sum rules

NASA Astrophysics Data System (ADS)

Cohen, Scott M.

2003-10-01

The range of validity of perturbative calculations of relativistic sum rules is investigated by calculating the second-order relativistic corrections to the Bethe sum rule and its small momentum limit, the Thomas-Reiche-Kuhn (TRK) sum rule. For the TRK sum rule and atomic systems, the second-order correction is found to be less than 0.5% up to about Z=70. The total relativistic corrections should then be accurate at least through this range of Z, and probably beyond this range if the second-order terms are included. For Rn (Z=86), however, the second-order corrections are nearly 1%. The total corrections to the Bethe sum rule are largest at small momentum, never being significantly larger than the corresponding corrections to the TRK sum rule. The first-order corrections to the Bethe sum rule also give better than 0.5% accuracy for Z<70, and inclusion of the second-order corrections should extend this range, as well.

Physical condition for elimination of ambiguity in conditionally convergent lattice sums

NASA Astrophysics Data System (ADS)

Young, K.

1987-02-01

The conditional convergence of the lattice sum defining the Madelung constant gives rise to an ambiguity in its value. It is shown that this ambiguity is related, through a simple and universal integral, to the average charge density on the crystal surface. The physically correct value is obtained by setting the charge density to zero. A simple and universally applicable formula for the Madelung constant is derived as a consequence. It consists of adding up dipole-dipole energies together with a nontrivial correction term.

Relativistic corrections to a generalized sum rule

NASA Astrophysics Data System (ADS)

Sinky, H.; Leung, P. T.

2006-09-01

Relativistic corrections to a previously established generalized sum rule are obtained using the Foldy-Wouthysen transformation. This sum rule derived previously by Wang [Phys. Rev. A 60, 262 (1999)] for a nonrelativistic system contains both the well-known Thomas-Reiche-Kuhn and Bethe sum rules, for which relativistic corrections have been obtained in the literature. Our results for the generalized formula will be applied to recover several results obtained previously in the literature, as well as to another sum rule whose relativistic corrections will be obtained.

Exact sum rules for inhomogeneous systems containing a zero mode

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

Amore, Paolo, E-mail: paolo.amore@gmail.com

2014-10-15

We show that the formulas for the sum rules for the eigenvalues of inhomogeneous systems that we have obtained in two recent papers are incomplete when the system contains a zero mode. We prove that there are finite contributions of the zero mode to the sum rules and we explicitly calculate the expressions for the sum rules of order one and two. The previous results for systems that do not contain a zero mode are unaffected. - Highlights: • We discuss the sum rules of the eigenvalues of inhomogeneous systems containing a zero mode. • We derive the explicit expressionsmore » for sum rules of order one and two. • We perform accurate numerical tests of these results for three examples.« less

Isoscalar compression modes within fluid dynamic approach

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

Kolomietz, V. M.; Cyclotron Institute, Texas A and M University, College Station, Texas 77843-3366; Shlomo, S.

2000-06-01

We study the nuclear isoscalar monopole and dipole compression modes in nuclei within the fluid dynamic approach (FDA) with and without the effect of relaxation. For a wide region of the medium and heavy nuclei, the FDA predicts that the isoscalar giant monopole resonance (ISGMR) and the isoscalar giant dipole resonance (ISGDR) exhaust about 90% of the corresponding model-independent sum rules. In the case of neglecting the effect of relaxation, the FDA, when adjusted to reproduce the centroid energy E0 of the ISGMR, results with centroid energy E1 of the ISGDR which is in agreement with the predictions of themore » self-consistent Hartree-Fock random-phase approximation calculations and the scaling model but significantly larger than the experimental value. We also show that the FDA leads to the correct hydrodynamic limit for the ratio (E1/E0){sub FDA}. We find that the ratio (E1/E0){sub FDA} depends on the relaxation time and approaches the preliminary experimental value (E1/E0){sub exp}=1.5{+-}0.1 in a short relaxation time limit. (c) 2000 The American Physical Society.« less

Computer simulations of equilibrium magnetization and microstructure in magnetic fluids

NASA Astrophysics Data System (ADS)

Rosa, A. P.; Abade, G. C.; Cunha, F. R.

2017-09-01

In this work, Monte Carlo and Brownian Dynamics simulations are developed to compute the equilibrium magnetization of a magnetic fluid under action of a homogeneous applied magnetic field. The particles are free of inertia and modeled as hard spheres with the same diameters. Two different periodic boundary conditions are implemented: the minimum image method and Ewald summation technique by replicating a finite number of particles throughout the suspension volume. A comparison of the equilibrium magnetization resulting from the minimum image approach and Ewald sums is performed by using Monte Carlo simulations. The Monte Carlo simulations with minimum image and lattice sums are used to investigate suspension microstructure by computing the important radial pair-distribution function go(r), which measures the probability density of finding a second particle at a distance r from a reference particle. This function provides relevant information on structure formation and its anisotropy through the suspension. The numerical results of go(r) are compared with theoretical predictions based on quite a different approach in the absence of the field and dipole-dipole interactions. A very good quantitative agreement is found for a particle volume fraction of 0.15, providing a validation of the present simulations. In general, the investigated suspensions are dominated by structures like dimmer and trimmer chains with trimmers having probability to form an order of magnitude lower than dimmers. Using Monte Carlo with lattice sums, the density distribution function g2(r) is also examined. Whenever this function is different from zero, it indicates structure-anisotropy in the suspension. The dependence of the equilibrium magnetization on the applied field, the magnetic particle volume fraction, and the magnitude of the dipole-dipole magnetic interactions for both boundary conditions are explored in this work. Results show that at dilute regimes and with moderate dipole-dipole interactions, the standard method of minimum image is both accurate and computationally efficient. Otherwise, lattice sums of magnetic particle interactions are required to accelerate convergence of the equilibrium magnetization. The accuracy of the numerical code is also quantitatively verified by comparing the magnetization obtained from numerical results with asymptotic predictions of high order in the particle volume fraction, in the presence of dipole-dipole interactions. In addition, Brownian Dynamics simulations are used in order to examine magnetization relaxation of a ferrofluid and to calculate the magnetic relaxation time as a function of the magnetic particle interaction strength for a given particle volume fraction and a non-dimensional applied field. The simulations of magnetization relaxation have shown the existence of a critical value of the dipole-dipole interaction parameter. For strength of the interactions below the critical value at a given particle volume fraction, the magnetic relaxation time is close to the Brownian relaxation time and the suspension has no appreciable memory. On the other hand, for strength of dipole interactions beyond its critical value, the relaxation time increases exponentially with the strength of dipole-dipole interaction. Although we have considered equilibrium conditions, the obtained results have far-reaching implications for the analysis of magnetic suspensions under external flow.

Energy-weighted sum rules connecting ΔZ = 2 nuclei within the SO(8) model

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

Štefánik, Dušan; Šimkovic, Fedor; Faessler, Amand

2013-12-30

Energy-weighted sum rules associated with ΔZ = 2 nuclei are obtained for the Fermi and the Gamow-Teller operators within the SO(8) model. It is found that there is a dominance of contribution of a single state of the intermediate nucleus to the sum rule. The results confirm founding obtained within the SO(5) model that the energy-weighted sum rules of ΔZ = 2 nuclei are governed by the residual interactions of nuclear Hamiltonian. A short discussion concerning some aspects of energy weighted sum rules in the case of realistic nuclei is included.

Direct surface magnetometry with photoemission magnetic x-ray dichroism

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

Tobin, J.G.; Goodman, K.W.; Schumann, F.O.

1997-04-01

Element specific surface magnetometry remains a central goal of synchrotron radiation based studies of nanomagnetic structures. One appealing possibility is the combination of x-ray absorption dichroism measurements and the theoretical framework provided by the {open_quotes}sum rules.{close_quotes} Unfortunately, sum rule analysis are hampered by several limitations including delocalization of the final state, multi-electronic phenomena and the presence of surface dipoles. An alternative experiment, Magnetic X-Ray Dichroism in Photoelectron Spectroscopy, holds out promise based upon its elemental specificity, surface sensitivity and high resolution. Computational simulations by Tamura et al. demonstrated the relationship between exchange and spin orbit splittings and experimental data ofmore » linear and circular dichroisms. Now the authors have developed an analytical framework which allows for the direct extraction of core level exchange splittings from circular and linear dichroic photoemission data. By extending a model initially proposed by Venus, it is possible to show a linear relation between normalized dichroism peaks in the experimental data and the underlying exchange splitting. Since it is reasonable to expect that exchange splittings and magnetic moments track together, this measurement thus becomes a powerful new tool for direct surface magnetometry, without recourse to time consuming and difficult spectral simulations. The theoretical derivation will be supported by high resolution linear and circular dichroism data collected at the Spectromicroscopy Facility of the Advanced Light Source.« less

Electron emission and recoil effects following the beta decay of He6

NASA Astrophysics Data System (ADS)

Schulhoff, Eva E.; Drake, G. W. F.

2015-11-01

Probabilities for atomic electron excitation (shake-up) and ionization (shake-off) are studied following the beta-decay process →Li+6He6+e-+ν¯e , and in particular, recoil-induced contributions to the shake-off probability are calculated within the nonrelativistic sudden approximation. A pseudostate expansion method together with Stieltjes imaging is used to represent the complete two-electron spectrum of final Li+6 ,Li26+, and Li36+ states. Results for the recoil correction show a 7 σ disagreement with the experiment of Carlson et al. [Phys. Rev. 129, 2220 (1963), 10.1103/PhysRev.129.2220]. A variety of sum rules, including a newly derived Thomas-Reich-Kuhn oscillator strength sum rule for dipole recoil terms, provides tight constraints on the accuracy of the results. Calculations are performed for the helium 1 s 2 s 3S metastable state, as well as for the 1 s21S ground state. Our results would reduce the recoil-induced correction to the measured electroneutrino coupling constant ae μ from the apparent 0.6% used in the experiments to 0.09%.

Exact sum rules for inhomogeneous strings

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

Amore, Paolo, E-mail: paolo.amore@gmail.com

2013-11-15

We derive explicit expressions for the sum rules of the eigenvalues of inhomogeneous strings with arbitrary density and with different boundary conditions. We show that the sum rule of order N may be obtained in terms of a diagrammatic expansion, with (N−1)!/2 independent diagrams. These sum rules are used to derive upper and lower bounds to the energy of the fundamental mode of an inhomogeneous string; we also show that it is possible to improve these approximations taking into account the asymptotic behavior of the spectrum and applying the Shanks transformation to the sequence of approximations obtained to the differentmore » orders. We discuss three applications of these results. -- Highlights: •We derive an explicit expression for the sum rules of an inhomogeneous string. •We obtain a diagrammatic representation for the sum rules of a given order. •We obtain precise bounds on the lowest eigenvalue of the string.« less

Compton scattering from nuclei and photo-absorption sum rules

NASA Astrophysics Data System (ADS)

Gorchtein, Mikhail; Hobbs, Timothy; Londergan, J. Timothy; Szczepaniak, Adam P.

2011-12-01

We revisit the photo-absorption sum rule for real Compton scattering from the proton and from nuclear targets. In analogy with the Thomas-Reiche-Kuhn sum rule appropriate at low energies, we propose a new “constituent quark model” sum rule that relates the integrated strength of hadronic resonances to the scattering amplitude on constituent quarks. We study the constituent quark model sum rule for several nuclear targets. In addition, we extract the α=0 pole contribution for both proton and nuclei. Using the modern high-energy proton data, we find that the α=0 pole contribution differs significantly from the Thomson term, in contrast with the original findings by Damashek and Gilman.

Accurate Predictions of Mean Geomagnetic Dipole Excursion and Reversal Frequencies, Mean Paleomagnetic Field Intensity, and the Radius of Earth's Core Using McLeod's Rule

NASA Technical Reports Server (NTRS)

Voorhies, Coerte V.; Conrad, Joy

1996-01-01

The geomagnetic spatial power spectrum R(sub n)(r) is the mean square magnetic induction represented by degree n spherical harmonic coefficients of the internal scalar potential averaged over the geocentric sphere of radius r. McLeod's Rule for the magnetic field generated by Earth's core geodynamo says that the expected core surface power spectrum (R(sub nc)(c)) is inversely proportional to (2n + 1) for 1 less than n less than or equal to N(sub E). McLeod's Rule is verified by locating Earth's core with main field models of Magsat data; the estimated core radius of 3485 kn is close to the seismologic value for c of 3480 km. McLeod's Rule and similar forms are then calibrated with the model values of R(sub n) for 3 less than or = n less than or = 12. Extrapolation to the degree 1 dipole predicts the expectation value of Earth's dipole moment to be about 5.89 x 10(exp 22) Am(exp 2)rms (74.5% of the 1980 value) and the expected geomagnetic intensity to be about 35.6 (mu)T rms at Earth's surface. Archeo- and paleomagnetic field intensity data show these and related predictions to be reasonably accurate. The probability distribution chi(exp 2) with 2n+1 degrees of freedom is assigned to (2n + 1)R(sub nc)/(R(sub nc). Extending this to the dipole implies that an exceptionally weak absolute dipole moment (less than or = 20% of the 1980 value) will exist during 2.5% of geologic time. The mean duration for such major geomagnetic dipole power excursions, one quarter of which feature durable axial dipole reversal, is estimated from the modern dipole power time-scale and the statistical model of excursions. The resulting mean excursion duration of 2767 years forces us to predict an average of 9.04 excursions per million years, 2.26 axial dipole reversals per million years, and a mean reversal duration of 5533 years. Paleomagnetic data show these predictions to be quite accurate. McLeod's Rule led to accurate predictions of Earth's core radius, mean paleomagnetic field intensity, and mean geomagnetic dipole power excursion and axial dipole reversal frequencies. We conclude that McLeod's Rule helps unify geo-paleomagnetism, correctly relates theoretically predictable statistical properties of the core geodynamo to magnetic observation, and provides a priori information required for stochastic inversion of paleo-, archeo-, and/or historical geomagnetic measurements.

Comparing T-odd and T-even spin sum rules

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

Teryaev, O.V.

2015-04-10

Sum rules for T-even and T-odd structure functions and parton distributions are considered. The case of spin-dependent distributions related to energy-momentum tensor (EMT) is specifically addressed. The Burkardt sum rule for T-odd Sivers functions may be related to EMT provided the imaginary prescription for gluonic pole correlator is incorporated. The momentum sum rule for deuteron tensor spin structure function allows one to probe indirectly the gravity couplings to quarks and gluons.

Compton Scattering and Photo-absorption Sum Rules on Nuclei

NASA Astrophysics Data System (ADS)

Gorshteyn, Mikhail; Hobbs, Timothy; Londergan, J. Timothy; Szczepaniak, Adam P.

2012-03-01

We revisit the photo-absorption sum rule for real Compton scattering from the proton and from nuclear targets. In analogy with the Thomas-Reiche-Kuhn sum rule appropriate at low energies, we propose a new ``constituent quark model'' sum rule that relates the integrated strength of hadronic resonances to the scattering amplitude on constituent quarks. We study the constituent quark model sum rule for several nuclear targets. In addition we extract the J=0 pole contribution for both proton and nuclei. Using the modern high energy proton data we find that the J=0 pole contribution differs significantly from the Thomson term, in contrast with the original findings by Damashek and Gilman. We discuss phenomenological implications of this new result.

Electromagnetic multipole moments of the P_c^+(4380) pentaquark in light-cone QCD

NASA Astrophysics Data System (ADS)

Özdem, U.; Azizi, K.

2018-05-01

We calculate the electromagnetic multipole moments of the P_c^+(4380) pentaquark by modeling it as the diquark-diquark-antiquark and {\\bar{D}}^*Σ _c molecular state with quantum numbers J^P = 3/2^-. In particular, the magnetic dipole, electric quadrupole and magnetic octupole moments of this particle are extracted in the framework of light-cone QCD sum rule. The values of the electromagnetic multipole moments obtained via two pictures differ substantially from each other, which can be used to pin down the underlying structure of P_c^+(4380). The comparison of any future experimental data on the electromagnetic multipole moments of the P_c^+(4380) pentaquark with the results of the present work can shed light on the nature and inner quark organization of this state.

Chiral corrections to the Adler-Weisberger sum rule

NASA Astrophysics Data System (ADS)

Beane, Silas R.; Klco, Natalie

2016-12-01

The Adler-Weisberger sum rule for the nucleon axial-vector charge, gA , offers a unique signature of chiral symmetry and its breaking in QCD. Its derivation relies on both algebraic aspects of chiral symmetry, which guarantee the convergence of the sum rule, and dynamical aspects of chiral symmetry breaking—as exploited using chiral perturbation theory—which allow the rigorous inclusion of explicit chiral symmetry breaking effects due to light-quark masses. The original derivations obtained the sum rule in the chiral limit and, without the benefit of chiral perturbation theory, made various attempts at extrapolating to nonvanishing pion masses. In this paper, the leading, universal, chiral corrections to the chiral-limit sum rule are obtained. Using PDG data, a recent parametrization of the pion-nucleon total cross sections in the resonance region given by the SAID group, as well as recent Roy-Steiner equation determinations of subthreshold amplitudes, threshold parameters, and correlated low-energy constants, the Adler-Weisberger sum rule is confronted with experimental data. With uncertainty estimates associated with the cross-section parametrization, the Goldberger-Treimann discrepancy, and the truncation of the sum rule at O (Mπ4) in the chiral expansion, this work finds gA=1.248 ±0.010 ±0.007 ±0.013 .

Level densities and γ-ray strength functions in Sn isotopes

NASA Astrophysics Data System (ADS)

Toft, H. K.; Larsen, A. C.; Agvaanluvsan, U.; Bürger, A.; Guttormsen, M.; Mitchell, G. E.; Nyhus, H. T.; Schiller, A.; Siem, S.; Syed, N. U. H.; Voinov, A.

2010-06-01

The nuclear level densities of Sn118,119 and the γ-ray strength functions of Sn116,118,119 below the neutron separation energy are extracted with the Oslo method using the (He3,αγ) and (He3,He3'γ) reactions. The level-density function of Sn119 displays steplike structures. The microcanonical entropies are deduced from the level densities, and the single neutron entropy of Sn119 is determined to be 1.7 ± 0.2 kB. Results from a combinatorial model support the interpretation that some of the low-energy steps in the level density function are caused by neutron pair breaking. An enhancement in all the γ-ray strength functions of Sn116-119, compared to standard models for radiative strength, is observed for the γ-ray energy region of ≃4-11 MeV. These small resonances all have a centroid energy of 8.0(1) MeV and an integrated strength corresponding to 1.7(9)% of the classical Thomas-Reiche-Kuhn sum rule. The Sn resonances may be due to electric dipole neutron skin oscillations or to an enhancement of the giant magnetic dipole resonance.

Forward Compton scattering with weak neutral current: Constraints from sum rules

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

Gorchtein, Mikhail; Zhang, Xilin

2015-06-09

We generalize forward real Compton amplitude to the case of the interference of the electromagnetic and weak neutral current, formulate a low-energy theorem, relate the new amplitudes to the interference structure functions and obtain a new set of sum rules. Furthermore, we address a possible new sum rule that relates the product of the axial charge and magnetic moment of the nucleon to the 0th moment of the structure function g5(ν, 0). For the dispersive γ Z-box correction to the proton’s weak charge, the application of the GDH sum rule allows us to reduce the uncertainty due to resonance contributionsmore » by a factor of two. Finally, the finite energy sum rule helps addressing the uncertainty in that calculation due to possible duality violations.« less

Sum Rules of Charm CP Asymmetries beyond the SU(3)_{F} Limit.

PubMed

Müller, Sarah; Nierste, Ulrich; Schacht, Stefan

2015-12-18

We find new sum rules between direct CP asymmetries in D meson decays with coefficients that can be determined from a global fit to branching ratio data. Our sum rules eliminate the penguin topologies P and PA, which cannot be determined from branching ratios. In this way, we can make predictions about direct CP asymmetries in the standard model without ad hoc assumptions on the sizes of penguin diagrams. We consistently include first-order SU(3)_{F} breaking in the topological amplitudes extracted from the branching ratios. By confronting our sum rules with future precise data from LHCb and Belle II, one will identify or constrain new-physics contributions to P or PA. The first sum rule correlates the CP asymmetries a_{CP}^{dir} in D^{0}→K^{+}K^{-}, D^{0}→π^{+}π^{-}, and D^{0}→π^{0}π^{0}. We study the region of the a_{CP}^{dir}(D^{0}→π^{+}π^{-})-a_{CP}^{dir}(D^{0}→π^{0}π^{0}) plane allowed by current data and find that our sum rule excludes more than half of the allowed region at 95% C.L. Our second sum rule correlates the direct CP asymmetries in D^{+}→K[over ¯]^{0}K^{+}, D_{s}^{+}→K^{0}π^{+}, and D_{s}^{+}→K^{+}π^{0}.

Experimental study of the electric dipole strength in the even Mo nuclei and its deformation dependence

NASA Astrophysics Data System (ADS)

Erhard, M.; Junghans, A. R.; Nair, C.; Schwengner, R.; Beyer, R.; Klug, J.; Kosev, K.; Wagner, A.; Grosse, E.

2010-03-01

Two methods based on bremsstrahlung were applied to the stable even Mo isotopes for the experimental determination of the photon strength function covering the high excitation energy range above 4 MeV with its increasing level density. Photon scattering was used up to the neutron separation energies Sn and data up to the maximum of the isovector giant resonance (GDR) were obtained by photoactivation. After a proper correction for multistep processes the observed quasicontinuous spectra of scattered photons show a remarkably good match to the photon strengths derived from nuclear photoeffect data obtained previously by neutron detection and corrected in absolute scale by using the new activation results. The combined data form an excellent basis to derive a shape dependence of the E1 strength in the even Mo isotopes with increasing deviation from the N=50 neutron shell (i.e., with the impact of quadrupole deformation and triaxiality). The wide energy coverage of the data allows for a stringent assessment of the dipole sum rule and a test of a novel parametrization developed previously which is based on it. This parametrization for the electric dipole strength function in nuclei with A>80 deviates significantly from prescriptions generally used previously. In astrophysical network calculations it may help to quantify the role the p-process plays in cosmic nucleosynthesis. It also has impact on the accurate analysis of neutron capture data of importance for future nuclear energy systems and waste transmutation.

Aspects of QCD current algebra on a null plane

NASA Astrophysics Data System (ADS)

Beane, S. R.; Hobbs, T. J.

2016-09-01

Consequences of QCD current algebra formulated on a light-like hyperplane are derived for the forward scattering of vector and axial-vector currents on an arbitrary hadronic target. It is shown that current algebra gives rise to a special class of sum rules that are direct consequences of the independent chiral symmetry that exists at every point on the two-dimensional transverse plane orthogonal to the lightlike direction. These sum rules are obtained by exploiting the closed, infinite-dimensional algebra satisfied by the transverse moments of null-plane axial-vector and vector charge distributions. In the special case of a nucleon target, this procedure leads to the Adler-Weisberger, Gerasimov-Drell-Hearn, Cabibbo-Radicati and Fubini-Furlan-Rossetti sum rules. Matching to the dispersion-theoretic language which is usually invoked in deriving these sum rules, the moment sum rules are shown to be equivalent to algebraic constraints on forward S-matrix elements in the Regge limit.

Force sum rules for stepped surfaces of jellium

NASA Astrophysics Data System (ADS)

Farjam, Mani

2007-03-01

The Budd-Vannimenus theorem for jellium surface is generalized for stepped surfaces of jellium. Our sum rules show that the average value of the electrostatic potential over the stepped jellium surface equals the value of the potential at the corresponding flat jellium surface. Several sum rules are tested with numerical results obtained within the Thomas-Fermi model of stepped surfaces.

Neyman-Pearson biometric score fusion as an extension of the sum rule

NASA Astrophysics Data System (ADS)

Hube, Jens Peter

2007-04-01

We define the biometric performance invariance under strictly monotonic functions on match scores as normalization symmetry. We use this symmetry to clarify the essential difference between the standard score-level fusion approaches of sum rule and Neyman-Pearson. We then express Neyman-Pearson fusion assuming match scores defined using false acceptance rates on a logarithmic scale. We show that by stating Neyman-Pearson in this form, it reduces to sum rule fusion for ROC curves with logarithmic slope. We also introduce a one parameter model of biometric performance and use it to express Neyman-Pearson fusion as a weighted sum rule.

Partial Photoneutron Cross Sections for 207,208Pb

NASA Astrophysics Data System (ADS)

Kondo, T.; Utsunomiya, H.; Goriely, S.; Iwamoto, C.; Akimune, H.; Yamagata, T.; Toyokawa, H.; Harada, H.; Kitatani, F.; Lui, Y.-W.; Hilaire, S.; Koning, A. J.

2014-05-01

Using linearly-polarized laser-Compton scattering γ-rays, partial E1 and M1 photoneutron cross sections along with total cross sections were determined for 207,208Pb at four energies near neutron threshold by measuring anisotropies in photoneutron emission. Separately, total photoneutron cross sections were measured for 207,208Pb with a high-efficiency 4π neutron detector. The partial cross section measurement provides direct evidence for the presence of pygmy dipole resonance (PDR) in 207,208Pb in the vicinity of neutron threshold. The strength of PDR amounts to 0.32%-0.42% of the Thomas-Reiche-Kuhn sum rule. Several μN2 units of B(M1)↑ strength were observed in 207,208Pb just above neutron threshold, which correspond to M1 cross sections less than 10% of the total photoneutron cross sections.

Probing cosmic anisotropy with gravitational waves as standard sirens

NASA Astrophysics Data System (ADS)

Cai, Rong-Gen; Liu, Tong-Bo; Liu, Xue-Wen; Wang, Shao-Jiang; Yang, Tao

2018-05-01

The gravitational wave (GW) as a standard siren directly determines the luminosity distance from the gravitational waveform without reference to the specific cosmological model, of which the redshift can be obtained separately by means of the electromagnetic counterpart like GW events from binary neutron stars and massive black hole binaries (MBHBs). To see to what extent the standard siren can reproduce the presumed dipole anisotropy written in the simulated data of standard siren events from typical configurations of GW detectors, we find that (1) for the Laser Interferometer Space Antenna with different MBHB models during five-year observations, the cosmic isotropy can be ruled out at 3 σ confidence level (C.L.) and the dipole direction can be constrained roughly around 20% at 2 σ C.L., as long as the dipole amplitude is larger than 0.04, 0.06 and 0.03 for MBHB models Q3d, pop III and Q3nod with increasing constraining ability, respectively; (2) for the Einstein telescope with no less than 200 standard siren events, the cosmic isotropy can be ruled out at 3 σ C.L. if the dipole amplitude is larger than 0.06, and the dipole direction can be constrained within 20% at 3 σ C.L. if the dipole amplitude is near 0.1; (3) for the Deci-Hertz Interferometer Gravitational wave Observatory with no less than 100 standard siren events, the cosmic isotropy can be ruled out at 3 σ C.L. for dipole amplitude larger than 0.03, and the dipole direction can even be constrained within 10% at 3 σ C.L. if the dipole amplitude is larger than 0.07. Our work manifests the promising perspective of the constraint ability on the cosmic anisotropy from the standard siren approach.

Isotropic C6, C8 and C10 interaction coefficients for CH 4, C 2H 6, C 3H 8, n-C 4H 10 and cyclo- C3H 6

NASA Astrophysics Data System (ADS)

Thomas, Gerald F.; Mulder, Fred; Meath, William J.

1980-12-01

The non-empirical generalized Kirkwood, Unsöld, and the single-Δ Unsöld methods (with double-zeta quality SCF wave-functions) are used to calculate isotropic dispersion (and induction) energy coefficients C2n, with n ⩽ 5, for interactions involving ground state CH 4, C 2H 6, C 3H 8, n-C 4H 10 and cyclo-C 3H 6. Results are also given for the related multipole polarizabilities α l, multipole sums S1/(0) and S1(-1) which are evaluated using sum rules, and the permanent multipole moments. for l = 1 (dipole) to l = 3 (octupole). Estimates of the reliability of the non-empirical methods, for the type of molecules considered, are obtained by a comparison with accurate literature values of α 1S1(-1) and C6. This, and the asymptotic properties of the multipolar expansion of the dispersion energy, the use to discuss recommended representation for the isotropic long range interaction energies through R-10 where R is the intermolecular separation.

Bjorken unpolarized and polarized sum rules: comparative analysis of large- NF expansions

NASA Astrophysics Data System (ADS)

Broadhurst, D. J.; Kataev, A. L.

2002-09-01

Analytical all-orders results are presented for the one-renormalon-chain contributions to the Bjorken unpolarized sum rule for the F1 structure function of νN deep-inelastic scattering in the large-NF limit. The feasibility of estimating higher order perturbative QCD corrections, by the process of naive nonabelianization (NNA), is studied, in anticipation of measurement of this sum rule at a Neutrino Factory. A comparison is made with similar estimates obtained for the Bjorken polarized sum rule. Application of the NNA procedure to correlators of quark vector and scalar currents, in the euclidean region, is compared with recent analytical results for the O(αs4NF2) terms.

Truncated Sum Rules and Their Use in Calculating Fundamental Limits of Nonlinear Susceptibilities

NASA Astrophysics Data System (ADS)

Kuzyk, Mark G.

Truncated sum rules have been used to calculate the fundamental limits of the nonlinear susceptibilities and the results have been consistent with all measured molecules. However, given that finite-state models appear to result in inconsistencies in the sum rules, it may seem unclear why the method works. In this paper, the assumptions inherent in the truncation process are discussed and arguments based on physical grounds are presented in support of using truncated sum rules in calculating fundamental limits. The clipped harmonic oscillator is used as an illustration of how the validity of truncation can be tested and several limiting cases are discussed as examples of the nuances inherent in the method.

Simple and accurate sum rules for highly relativistic systems

NASA Astrophysics Data System (ADS)

Cohen, Scott M.

2005-03-01

In this paper, I consider the Bethe and Thomas-Reiche-Kuhn sum rules, which together form the foundation of Bethe's theory of energy loss from fast charged particles to matter. For nonrelativistic target systems, the use of closure leads directly to simple expressions for these quantities. In the case of relativistic systems, on the other hand, the calculation of sum rules is fraught with difficulties. Various perturbative approaches have been used over the years to obtain relativistic corrections, but these methods fail badly when the system in question is very strongly bound. Here, I present an approach that leads to relatively simple expressions yielding accurate sums, even for highly relativistic many-electron systems. I also offer an explanation for the difference between relativistic and nonrelativistic sum rules in terms of the Zitterbewegung of the electrons.

Theoretical and observational analysis of spacecraft fields

NASA Technical Reports Server (NTRS)

Neubauer, F. M.; Schatten, K. H.

1972-01-01

In order to investigate the nondipolar contributions of spacecraft magnetic fields a simple magnetic field model is proposed. This model consists of randomly oriented dipoles in a given volume. Two sets of formulas are presented which give the rms-multipole field components, for isotropic orientations of the dipoles at given positions and for isotropic orientations of the dipoles distributed uniformly throughout a cube or sphere. The statistical results for an 8 cu m cube together with individual examples computed numerically show the following features: Beyond about 2 to 3 m distance from the center of the cube, the field is dominated by an equivalent dipole. The magnitude of the magnetic moment of the dipolar part is approximated by an expression for equal magnetic moments or generally by the Pythagorean sum of the dipole moments. The radial component is generally greater than either of the transverse components for the dipole portion as well as for the nondipolar field contributions.

Sum rules and other properties involving resonance projection operators. [for optical potential description of electron scattering from atoms and ions

NASA Technical Reports Server (NTRS)

Berk, A.; Temkin, A.

1985-01-01

A sum rule is derived for the auxiliary eigenvalues of an equation whose eigenspectrum pertains to projection operators which describe electron scattering from multielectron atoms and ions. The sum rule's right-hand side depends on an integral involving the target system eigenfunctions. The sum rule is checked for several approximations of the two-electron target. It is shown that target functions which have a unit eigenvalue in their auxiliary eigenspectrum do not give rise to well-defined projection operators except through a limiting process. For Hylleraas target approximations, the auxiliary equations are shown to contain an infinite spectrum. However, using a Rayleigh-Ritz variational principle, it is shown that a comparatively simple aproximation can exhaust the sum rule to better than five significant figures. The auxiliary Hylleraas equation is greatly simplified by conversion to a square root equation containing the same eigenfunction spectrum and from which the required eigenvalues are trivially recovered by squaring.

Neutrino mass sum-rule

NASA Astrophysics Data System (ADS)

Damanik, Asan

2018-03-01

Neutrino mass sum-rele is a very important research subject from theoretical side because neutrino oscillation experiment only gave us two squared-mass differences and three mixing angles. We review neutrino mass sum-rule in literature that have been reported by many authors and discuss its phenomenological implications.

Influence of complex configurations on properties of pygmy dipole resonances

NASA Astrophysics Data System (ADS)

Arsenyev, N. N.; Severyukhin, A. P.; Voronov, V. V.; Van Giai, Nguyen

2018-05-01

Starting from the quasiparticle random phase approximation based on the Skyrme interaction SLy5, we study the effects of phonon-phonon coupling (PPC) on the low-energy electric dipole responses in some spherical nuclei. The inclusion of the PPC results in the formation of low-energy 1‑ states. There is an impact of the PPC effect on low-energy E1 strength. The PPC effect on the electric dipole polarizability is discussed. We predict a strong increase of the summed E1 strength below 10 MeV, with increasing neutron number from 48Ca till 58Ca.

The spatiotemporal MEG covariance matrix modeled as a sum of Kronecker products.

PubMed

Bijma, Fetsje; de Munck, Jan C; Heethaar, Rob M

2005-08-15

The single Kronecker product (KP) model for the spatiotemporal covariance of MEG residuals is extended to a sum of Kronecker products. This sum of KP is estimated such that it approximates the spatiotemporal sample covariance best in matrix norm. Contrary to the single KP, this extension allows for describing multiple, independent phenomena in the ongoing background activity. Whereas the single KP model can be interpreted by assuming that background activity is generated by randomly distributed dipoles with certain spatial and temporal characteristics, the sum model can be physiologically interpreted by assuming a composite of such processes. Taking enough terms into account, the spatiotemporal sample covariance matrix can be described exactly by this extended model. In the estimation of the sum of KP model, it appears that the sum of the first 2 KP describes between 67% and 93%. Moreover, these first two terms describe two physiological processes in the background activity: focal, frequency-specific alpha activity, and more widespread non-frequency-specific activity. Furthermore, temporal nonstationarities due to trial-to-trial variations are not clearly visible in the first two terms, and, hence, play only a minor role in the sample covariance matrix in terms of matrix power. Considering the dipole localization, the single KP model appears to describe around 80% of the noise and seems therefore adequate. The emphasis of further improvement of localization accuracy should be on improving the source model rather than the covariance model.

Ground state of dipolar hard spheres confined in channels

NASA Astrophysics Data System (ADS)

Deißenbeck, Florian; Löwen, Hartmut; Oǧuz, Erdal C.

2018-05-01

We investigate the ground state of a classical two-dimensional system of hard-sphere dipoles confined between two hard walls. Using lattice sum minimization techniques we reveal that at fixed wall separations, a first-order transition from a vacuum to a straight one-dimensional chain of dipoles occurs upon increasing the density. Further increase in the density yields the stability of an undulated chain as well as nontrivial buckling structures. We explore the close-packed configurations of dipoles in detail, and we find that, in general, the densest packings of dipoles possess complex magnetizations along the principal axis of the slit. Our predictions serve as a guideline for experiments with granular dipolar and magnetic colloidal suspensions confined in slitlike channel geometry.

Trends in magnetism of free Rh clusters via relativistic ab-initio calculations.

PubMed

Šipr, O; Ebert, H; Minár, J

2015-02-11

A fully relativistic ab-initio study on free Rh clusters of 13-135 atoms is performed to identify general trends concerning their magnetism and to check whether concepts which proved to be useful in interpreting magnetism of 3d metals are applicable to magnetism of 4d systems. We found that there is no systematic relation between local magnetic moments and coordination numbers. On the other hand, the Stoner model appears well-suited both as a criterion for the onset of magnetism and as a guide for the dependence of local magnetic moments on the site-resolved density of states at the Fermi level. Large orbital magnetic moments antiparallel to spin magnetic moments were found for some sites. The intra-atomic magnetic dipole Tz term can be quite large at certain sites but as a whole it is unlikely to affect the interpretation of x-ray magnetic circular dichroism experiments based on the sum rules.

Signatures of the A2 term in ultrastrongly coupled oscillators

NASA Astrophysics Data System (ADS)

Tufarelli, Tommaso; McEnery, K. R.; Maier, S. A.; Kim, M. S.

2015-06-01

We study a bosonic matter excitation coupled to a single-mode cavity field via electric dipole. Counter-rotating and A2 terms are included in the interaction model, A being the vector potential of the cavity field. In the ultrastrong coupling regime the vacuum of the bare modes is no longer the ground state of the Hamiltonian and contains a nonzero population of polaritons, the true normal modes of the system. If the parameters of the model satisfy the Thomas-Reiche-Kuhn sum rule, we find that the two polaritons are always equally populated. We show how this prediction could be tested in a quenching experiment, by rapidly switching on the coupling and analyzing the radiation emitted by the cavity. A refinement of the model based on a microscopic minimal coupling Hamiltonian is also provided, and its consequences on our results are characterized analytically.

Total and partial photoneutron cross sections for Pb isotopes

NASA Astrophysics Data System (ADS)

Kondo, T.; Utsunomiya, H.; Goriely, S.; Daoutidis, I.; Iwamoto, C.; Akimune, H.; Okamoto, A.; Yamagata, T.; Kamata, M.; Itoh, O.; Toyokawa, H.; Lui, Y.-W.; Harada, H.; Kitatani, F.; Hilaire, S.; Koning, A. J.

2012-07-01

Using quasimonochromatic laser-Compton scattering γ rays, total photoneutron cross sections were measured for 206,207,208Pb near neutron threshold with a high-efficiency 4π neutron detector. Partial E1 and M1 photoneutron cross sections along with total cross sections were determined for 207,208Pb at four energies near threshold by measuring anisotropies in photoneutron emission with linearly polarized γ rays. The E1 strength dominates over the M1 strength in the neutron channel where E1 photoneutron cross sections show extra strength of the pygmy dipole resonance in 207,208Pb near the neutron threshold corresponding to 0.32%-0.42% of the Thomas-Reiche-Kuhn sum rule. Several μN2 units of B(M1)↑ strength were observed in 207,208Pb just above neutron threshold, which correspond to an M1 cross section less than 10% of the total photoneutron cross section.

Diagonalizing Tensor Covariants, Light-Cone Commutators, and Sum Rules

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

Lo, C. Y.

We derive fixed-mass sum rules for virtual Compton scattering the forward direction. We use the methods of both Dicus, Jackiw, and Teplitz (for the absorptive parts) and Heimann, Hey, and Mandula (for the real parts). We find a set of tensor covariansa such that the corresponding scalar amplitudes are proportional to simple t-channel parity-conserving helicity amplitudes. We give a relatively complete discussion of the convergence of the sum rules in a Regge model. (auth)

The complete O (αs2) non-singlet heavy flavor corrections to the structure functions g1,2ep (x ,Q2), F1,2,Lep (x ,Q2), F1,2,3ν (ν bar) (x ,Q2) and the associated sum rules

NASA Astrophysics Data System (ADS)

Blümlein, Johannes; Falcioni, Giulio; De Freitas, Abilio

2016-09-01

We calculate analytically the flavor non-singlet O (αs2) massive Wilson coefficients for the inclusive neutral current non-singlet structure functions F1,2,Lep (x ,Q2) and g1,2ep (x ,Q2) and charged current non-singlet structure functions F1,2,3ν (ν bar) p (x ,Q2), at general virtualities Q2 in the deep-inelastic region. Numerical results are presented. We illustrate the transition from low to large virtualities for these observables, which may be contrasted to basic assumptions made in the so-called variable flavor number scheme. We also derive the corresponding results for the Adler sum rule, the unpolarized and polarized Bjorken sum rules and the Gross-Llewellyn Smith sum rule. There are no logarithmic corrections at large scales Q2 and the effects of the power corrections due to the heavy quark mass are of the size of the known O (αs4) corrections in the case of the sum rules. The complete charm and bottom corrections are compared to the approach using asymptotic representations in the region Q2 ≫mc,b2. We also study the target mass corrections to the above sum rules.

A comprehensive revisit of the ρ meson with improved Monte-Carlo based QCD sum rules

NASA Astrophysics Data System (ADS)

Wang, Qi-Nan; Zhang, Zhu-Feng; Steele, T. G.; Jin, Hong-Ying; Huang, Zhuo-Ran

2017-07-01

We improve the Monte-Carlo based QCD sum rules by introducing the rigorous Hölder-inequality-determined sum rule window and a Breit-Wigner type parametrization for the phenomenological spectral function. In this improved sum rule analysis methodology, the sum rule analysis window can be determined without any assumptions on OPE convergence or the QCD continuum. Therefore, an unbiased prediction can be obtained for the phenomenological parameters (the hadronic mass and width etc.). We test the new approach in the ρ meson channel with re-examination and inclusion of α s corrections to dimension-4 condensates in the OPE. We obtain results highly consistent with experimental values. We also discuss the possible extension of this method to some other channels. Supported by NSFC (11175153, 11205093, 11347020), Open Foundation of the Most Important Subjects of Zhejiang Province, and K. C. Wong Magna Fund in Ningbo University, TGS is Supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), Z. F. Zhang and Z. R. Huang are Grateful to the University of Saskatchewan for its Warm Hospitality

Generalized Thomas-Reiche-Kuhn sum rule

NASA Astrophysics Data System (ADS)

Zhou, Bing-Lu; Zhu, Jiong-Ming; Yan, Zong-Chao

2006-01-01

The generalized Thomas-Reiche-Kuhn sum rule is established for any Coulombic system with arbitrary masses and charges of its constituent particles. Numerical examples are given for the hydrogen molecular ions.

QCD Sum Rules for Magnetically Induced Mixing between ηc and J/ψ

DOE PAGES

Cho, Sungtae; Hattori, Koichi; Lee, Su Houng; ...

2014-10-20

We investigate the properties of charmonia in strong magnetic fields by using QCD sum rules. We show how to implement the mixing effects between ηc and J/ψ on the basis of field-theoretical approaches, and then show that the sum rules are saturated by the mixing effects with phenomenologically determined parameters. Consequently, we find that the mixing effects are the dominant contribution to the mass shifts of the static charmonia in strong magnetic fields.

QCD Sum Rules and Models for Generalized Parton Distributions

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

Anatoly Radyushkin

2004-10-01

I use QCD sum rule ideas to construct models for generalized parton distributions. To this end, the perturbative parts of QCD sum rules for the pion and nucleon electromagnetic form factors are interpreted in terms of GPDs and two models are discussed. One of them takes the double Borel transform at adjusted value of the Borel parameter as a model for nonforward parton densities, and another is based on the local duality relation. Possible ways of improving these Ansaetze are briefly discussed.

Exact sum rules for inhomogeneous drums

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

Amore, Paolo, E-mail: paolo.amore@gmail.com

2013-09-15

We derive general expressions for the sum rules of the eigenvalues of drums of arbitrary shape and arbitrary density, obeying different boundary conditions. The formulas that we present are a generalization of the analogous formulas for one dimensional inhomogeneous systems that we have obtained in a previous paper. We also discuss the extension of these formulas to higher dimensions. We show that in the special case of a density depending only on one variable the sum rules of any integer order can be expressed in terms of a single series. As an application of our result we derive exact summore » rules for the homogeneous circular annulus with different boundary conditions, for a homogeneous circular sector and for a radially inhomogeneous circular annulus with Dirichlet boundary conditions. -- Highlights: •We derive an explicit expression for the sum rules of inhomogeneous drums. •We discuss the extension to higher dimensions. •We discuss the special case of an inhomogeneity only along one direction.« less

Modified Kramers-Kronig relations and sum rules for meromorphic total refractive index

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

Peiponen, Kai-Erik; Saarinen, Jarkko J.; Vartiainen, Erik M.

2003-08-01

Modified Kramers-Kronig relations and corresponding sum rules are shown to hold for the total refractive index that can be presented as a sum of complex linear and nonlinear refractive indices, respectively. It is suggested that a self-action process, involving the degenerate third-order nonlinear susceptibility, can yield a negative total refractive index at some spectral range.

Sum rule for rate and CP asymmetry in B+ →K+π0

NASA Astrophysics Data System (ADS)

Gronau, Michael; Rosner, Jonathan L.

2007-01-01

A sum rule relating the ratio Rc = 2 Γ (B+ →K+π0) / Γ (B+ →K0π+) and the CP asymmetry ACP (B+ →K+π0) is proved to first order in the ratio of tree to penguin amplitudes. The sum rule explains why it is possible to have Rc consistent with 1 together with a small CP asymmetry in B+ →K+π0. The measured ratio ACP (B+ →K+π0) /ACP (B0 →K+π-) rules out a small strong phase difference between a color-suppressed and a color-favored tree amplitude contributing to B+ →K+π0 as favored by QCD factorization.

Optical Thomas-Reiche-Kuhn sum rules.

PubMed

Barnett, Stephen M; Loudon, Rodney

2012-01-06

The Thomas-Reiche-Kuhn sum rule is a fundamental consequence of the position-momentum commutation relation for an atomic electron and it provides an important constraint on the transition matrix elements for an atom. Analogously, the commutation relations for the electromagnetic field operators in a magnetodielectric medium constrain the properties of the dispersion relations for the medium through four sum rules for the allowed phase and group velocities for polaritons propagating through the medium. These rules apply to all bulk media including the metamaterials designed to provide negative refractive indices. An immediate consequence of this is that it is not possible to construct a medium in which all the polariton modes for a given wavelength lie in the negative-index region.

Optical Thomas-Reiche-Kuhn Sum Rules

NASA Astrophysics Data System (ADS)

Barnett, Stephen M.; Loudon, Rodney

2012-01-01

The Thomas-Reiche-Kuhn sum rule is a fundamental consequence of the position-momentum commutation relation for an atomic electron and it provides an important constraint on the transition matrix elements for an atom. Analogously, the commutation relations for the electromagnetic field operators in a magnetodielectric medium constrain the properties of the dispersion relations for the medium through four sum rules for the allowed phase and group velocities for polaritons propagating through the medium. These rules apply to all bulk media including the metamaterials designed to provide negative refractive indices. An immediate consequence of this is that it is not possible to construct a medium in which all the polariton modes for a given wavelength lie in the negative-index region.

Finite amplitude method applied to the giant dipole resonance in heavy rare-earth nuclei

NASA Astrophysics Data System (ADS)

Oishi, Tomohiro; Kortelainen, Markus; Hinohara, Nobuo

2016-03-01

Background: The quasiparticle random phase approximation (QRPA), within the framework of nuclear density functional theory (DFT), has been a standard tool to access the collective excitations of atomic nuclei. Recently, the finite amplitude method (FAM) was developed in order to perform the QRPA calculations efficiently without any truncation on the two-quasiparticle model space. Purpose: We discuss the nuclear giant dipole resonance (GDR) in heavy rare-earth isotopes, for which the conventional matrix diagonalization of the QRPA is numerically demanding. A role of the Thomas-Reiche-Kuhn (TRK) sum rule enhancement factor, connected to the isovector effective mass, is also investigated. Methods: The electric dipole photoabsorption cross section was calculated within a parallelized FAM-QRPA scheme. We employed the Skyrme energy density functional self-consistently in the DFT calculation for the ground states and FAM-QRPA calculation for the excitations. Results: The mean GDR frequency and width are mostly reproduced with the FAM-QRPA, when compared to experimental data, although some deficiency is observed with isotopes heavier than erbium. A role of the TRK enhancement factor in actual GDR strength is clearly shown: its increment leads to a shift of the GDR strength to higher-energy region, without a significant change in the transition amplitudes. Conclusions: The newly developed FAM-QRPA scheme shows remarkable efficiency, which enables one to perform systematic analysis of GDR for heavy rare-earth nuclei. The theoretical deficiency of the photoabsorption cross section could not be improved by only adjusting the TRK enhancement factor, suggesting the necessity of an approach beyond self-consistent QRPA and/or a more systematic optimization of the energy density functional (EDF) parameters.

Study of photo-proton reactions driven by bremsstrahlung radiation of high-intensity laser generated electrons

NASA Astrophysics Data System (ADS)

Spohr, K. M.; Shaw, M.; Galster, W.; Ledingham, K. W. D.; Robson, L.; Yang, J. M.; McKenna, P.; McCanny, T.; Melone, J. J.; Amthor, K.-U.; Ewald, F.; Liesfeld, B.; Schwoerer, H.; Sauerbrey, R.

2008-04-01

Photo-nuclear reactions were investigated using a high power table-top laser. The laser system at the University of Jena (I ~ 3-5×1019 W cm-2) produced hard bremsstrahlung photons (kT~2.9 MeV) via a laser-gas interaction which served to induce (γ, p) and (γ, n) reactions in Mg, Ti, Zn and Mo isotopes. Several (γ, p) decay channels were identified using nuclear activation analysis to determine their integral reaction yields. As the laser-generated bremsstrahlung spectra stretches over the energy regime dominated by the giant dipole resonance (GDR), these yield measurements were used in conjunction with theoretical estimates of the resonance energies Eres and their widths Γres to derive the integral reaction cross-section σint(γ,p) for 25Mn, 48, 49Ti, 68Zn and 97, 98Mo isotopes for the first time. This study enabled the determination of the previously unknown \\frac{{\\sigma}^int(\\gamma,n)}{{\\sigma}^int(\\gamma,p)} cross-section ratios for these isotopes. The experiments were supported by extensive model calculations (Empire) and the results were compared to the Thomas-Reiche-Kuhn (TRK) dipole sum rule as well as to the experimental data in neighboring isotopes and good agreement was observed. The Coulomb barrier and the neutron excess strongly influence the \\frac{{\\sigma}^int(\\gamma,n)}{{\\sigma}^int(\\gamma,p)} ratios for increasing target proton and neutron numbers.

Sum rules for quasifree scattering of hadrons

NASA Astrophysics Data System (ADS)

Peterson, R. J.

2018-02-01

The areas d σ /d Ω of fitted quasifree scattering peaks from bound nucleons for continuum hadron-nucleus spectra measuring d2σ /d Ω d ω are converted to sum rules akin to the Coulomb sums familiar from continuum electron scattering spectra from nuclear charge. Hadronic spectra with or without charge exchange of the beam are considered. These sums are compared to the simple expectations of a nonrelativistic Fermi gas, including a Pauli blocking factor. For scattering without charge exchange, the hadronic sums are below this expectation, as also observed with Coulomb sums. For charge exchange spectra, the sums are near or above the simple expectation, with larger uncertainties. The strong role of hadron-nucleon in-medium total cross sections is noted from use of the Glauber model.

Nucleon QCD sum rules in the instanton medium

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

Ryskin, M. G.; Drukarev, E. G., E-mail: drukarev@pnpi.spb.ru; Sadovnikova, V. A.

2015-09-15

We try to find grounds for the standard nucleon QCD sum rules, based on a more detailed description of the QCD vacuum. We calculate the polarization operator of the nucleon current in the instanton medium. The medium (QCD vacuum) is assumed to be a composition of the small-size instantons and some long-wave gluon fluctuations. We solve the corresponding QCD sum rule equations and demonstrate that there is a solution with the value of the nucleon mass close to the physical one if the fraction of the small-size instantons contribution is w{sub s} ≈ 2/3.

Large-Nc masses of light mesons from QCD sum rules for nonlinear radial Regge trajectories

NASA Astrophysics Data System (ADS)

Afonin, S. S.; Solomko, T. D.

2018-04-01

The large-Nc masses of light vector, axial, scalar and pseudoscalar mesons are calculated from QCD spectral sum rules for a particular ansatz interpolating the radial Regge trajectories. The ansatz includes a linear part plus exponentially degreasing corrections to the meson masses and residues. The form of corrections was proposed some time ago for consistency with analytical structure of Operator Product Expansion of the two-point correlation functions. We revised that original analysis and found the second solution for the proposed sum rules. The given solution describes better the spectrum of vector and axial mesons.

Charmonium ground and excited states at finite temperature from complex Borel sum rules

NASA Astrophysics Data System (ADS)

Araki, Ken-Ji; Suzuki, Kei; Gubler, Philipp; Oka, Makoto

2018-05-01

Charmonium spectral functions in vector and pseudoscalar channels at finite temperature are investigated through the complex Borel sum rules and the maximum entropy method. Our approach enables us to extract the peaks corresponding to the excited charmonia, ψ‧ and ηc‧ , as well as those of the ground states, J / ψ and ηc, which has never been achieved in usual QCD sum rule analyses. We show the spectral functions in vacuum and their thermal modification around the critical temperature, which leads to the almost simultaneous melting (or peak disappearance) of the ground and excited states.

Can the oscillator strength of the quantum dot bandgap transition exceed unity?

NASA Astrophysics Data System (ADS)

Hens, Z.

2008-10-01

We discuss the apparent contradiction between the Thomas-Reiche-Kuhn sum rule for oscillator strengths and recent experimental data on the oscillator strength of the band gap transition of quantum dots. Starting from two simple single electron model systems, we show that the sum rule does not limit this oscillator strength to values below unity, or below the number of electrons in the highest occupied single electron state. The only upper limit the sum rule imposes on the oscillator strength of the quantum dot band gap transition is the total number of electrons in the quantum dot.

Counter-ions at single charged wall: Sum rules.

PubMed

Samaj, Ladislav

2013-09-01

For inhomogeneous classical Coulomb fluids in thermal equilibrium, like the jellium or the two-component Coulomb gas, there exists a variety of exact sum rules which relate the particle one-body and two-body densities. The necessary condition for these sum rules is that the Coulomb fluid possesses good screening properties, i.e. the particle correlation functions or the averaged charge inhomogeneity, say close to a wall, exhibit a short-range (usually exponential) decay. In this work, we study equilibrium statistical mechanics of an electric double layer with counter-ions only, i.e. a globally neutral system of equally charged point-like particles in the vicinity of a plain hard wall carrying a fixed uniform surface charge density of opposite sign. At large distances from the wall, the one-body and two-body counter-ion densities go to zero slowly according to the inverse-power law. In spite of the absence of screening, all known sum rules are shown to hold for two exactly solvable cases of the present system: in the weak-coupling Poisson-Boltzmann limit (in any spatial dimension larger than one) and at a special free-fermion coupling constant in two dimensions. This fact indicates an extended validity of the sum rules and provides a consistency check for reasonable theoretical approaches.

Complex-energy approach to sum rules within nuclear density functional theory

DOE PAGES

Hinohara, Nobuo; Kortelainen, Markus; Nazarewicz, Witold; ...

2015-04-27

The linear response of the nucleus to an external field contains unique information about the effective interaction, correlations governing the behavior of the many-body system, and properties of its excited states. To characterize the response, it is useful to use its energy-weighted moments, or sum rules. By comparing computed sum rules with experimental values, the information content of the response can be utilized in the optimization process of the nuclear Hamiltonian or nuclear energy density functional (EDF). But the additional information comes at a price: compared to the ground state, computation of excited states is more demanding. To establish anmore » efficient framework to compute energy-weighted sum rules of the response that is adaptable to the optimization of the nuclear EDF and large-scale surveys of collective strength, we have developed a new technique within the complex-energy finite-amplitude method (FAM) based on the quasiparticle random- phase approximation. The proposed sum-rule technique based on the complex-energy FAM is a tool of choice when optimizing effective interactions or energy functionals. The method is very efficient and well-adaptable to parallel computing. As a result, the FAM formulation is especially useful when standard theorems based on commutation relations involving the nuclear Hamiltonian and external field cannot be used.« less

Practical implementation of the double linear damage rule and damage curve approach for treating cumulative fatigue damage

NASA Technical Reports Server (NTRS)

Manson, S. S.; Halford, G. R.

1980-01-01

Simple procedures are presented for treating cumulative fatigue damage under complex loading history using either the damage curve concept or the double linear damage rule. A single equation is provided for use with the damage curve approach; each loading event providing a fraction of damage until failure is presumed to occur when the damage sum becomes unity. For the double linear damage rule, analytical expressions are provided for determining the two phases of life. The procedure involves two steps, each similar to the conventional application of the commonly used linear damage rule. When the sum of cycle ratios based on phase 1 lives reaches unity, phase 1 is presumed complete, and further loadings are summed as cycle ratios on phase 2 lives. When the phase 2 sum reaches unity, failure is presumed to occur. No other physical properties or material constants than those normally used in a conventional linear damage rule analysis are required for application of either of the two cumulative damage methods described. Illustrations and comparisons of both methods are discussed.

Practical implementation of the double linear damage rule and damage curve approach for treating cumulative fatigue damage

NASA Technical Reports Server (NTRS)

Manson, S. S.; Halford, G. R.

1981-01-01

Simple procedures are given for treating cumulative fatigue damage under complex loading history using either the damage curve concept or the double linear damage rule. A single equation is given for use with the damage curve approach; each loading event providing a fraction of damage until failure is presumed to occur when the damage sum becomes unity. For the double linear damage rule, analytical expressions are given for determining the two phases of life. The procedure comprises two steps, each similar to the conventional application of the commonly used linear damage rule. Once the sum of cycle ratios based on Phase I lives reaches unity, Phase I is presumed complete, and further loadings are summed as cycle ratios based on Phase II lives. When the Phase II sum attains unity, failure is presumed to occur. It is noted that no physical properties or material constants other than those normally used in a conventional linear damage rule analysis are required for application of either of the two cumulative damage methods described. Illustrations and comparisons are discussed for both methods.

Comparative study of multimodal biometric recognition by fusion of iris and fingerprint.

PubMed

Benaliouche, Houda; Touahria, Mohamed

2014-01-01

This research investigates the comparative performance from three different approaches for multimodal recognition of combined iris and fingerprints: classical sum rule, weighted sum rule, and fuzzy logic method. The scores from the different biometric traits of iris and fingerprint are fused at the matching score and the decision levels. The scores combination approach is used after normalization of both scores using the min-max rule. Our experimental results suggest that the fuzzy logic method for the matching scores combinations at the decision level is the best followed by the classical weighted sum rule and the classical sum rule in order. The performance evaluation of each method is reported in terms of matching time, error rates, and accuracy after doing exhaustive tests on the public CASIA-Iris databases V1 and V2 and the FVC 2004 fingerprint database. Experimental results prior to fusion and after fusion are presented followed by their comparison with related works in the current literature. The fusion by fuzzy logic decision mimics the human reasoning in a soft and simple way and gives enhanced results.

Comparative Study of Multimodal Biometric Recognition by Fusion of Iris and Fingerprint

PubMed Central

Benaliouche, Houda; Touahria, Mohamed

2014-01-01

This research investigates the comparative performance from three different approaches for multimodal recognition of combined iris and fingerprints: classical sum rule, weighted sum rule, and fuzzy logic method. The scores from the different biometric traits of iris and fingerprint are fused at the matching score and the decision levels. The scores combination approach is used after normalization of both scores using the min-max rule. Our experimental results suggest that the fuzzy logic method for the matching scores combinations at the decision level is the best followed by the classical weighted sum rule and the classical sum rule in order. The performance evaluation of each method is reported in terms of matching time, error rates, and accuracy after doing exhaustive tests on the public CASIA-Iris databases V1 and V2 and the FVC 2004 fingerprint database. Experimental results prior to fusion and after fusion are presented followed by their comparison with related works in the current literature. The fusion by fuzzy logic decision mimics the human reasoning in a soft and simple way and gives enhanced results. PMID:24605065

Stark effect and dipole moments of the ammonia dimer in different vibration-rotation-tunneling states

NASA Astrophysics Data System (ADS)

Cotti, Gina; Linnartz, Harold; Meerts, W. Leo; van der Avoird, Ad; Olthof, Edgar H. T.

1996-03-01

In this paper we present Stark measurements on the G:K=-1 vibration-rotation-tunneling (VRT) transition, band origin 747.2 GHz, of the ammonia dimer. The observed splitting pattern and selection rules can be explained by considering the G36 and G144 symmetries of the inversion states involved, and almost complete mixing of these states by the applied electric field. The absolute values of the electric dipole moments of the ground and excited state are determined to be 0.763(15) and 0.365(10) D, respectively. From the theoretical analysis and the observed selection rules it is possible to establish that the dipole moments of the two interchange states must have opposite sign. The theoretical calculations are in good agreement with the experimental results: The calculated dipole moments are -0.74 D for the lower and +0.35 D for the higher state. Our results, in combination with the earlier dipole measurements on the G:K=0 ground state and the G:K=1 transition with band origin 486.8 GHz, confirm that the ammonia dimer is highly nonrigid. Its relatively small and strongly K-dependent dipole moment, which changes sign upon far-infrared excitation, originates from the difference in dynamical behavior of ortho and para NH3.

Relativistic and Nuclear Medium Effects on the Coulomb Sum Rule.

PubMed

Cloët, Ian C; Bentz, Wolfgang; Thomas, Anthony W

2016-01-22

In light of the forthcoming high precision quasielastic electron scattering data from Jefferson Lab, it is timely for the various approaches to nuclear structure to make robust predictions for the associated response functions. With this in mind, we focus here on the longitudinal response function and the corresponding Coulomb sum rule for isospin-symmetric nuclear matter at various baryon densities. Using a quantum field-theoretic quark-level approach which preserves the symmetries of quantum chromodynamics, as well as exhibiting dynamical chiral symmetry breaking and quark confinement, we find a dramatic quenching of the Coulomb sum rule for momentum transfers |q|≳0.5  GeV. The main driver of this effect lies in changes to the proton Dirac form factor induced by the nuclear medium. Such a dramatic quenching of the Coulomb sum rule was not seen in a recent quantum Monte Carlo calculation for carbon, suggesting that the Jefferson Lab data may well shed new light on the explicit role of QCD in nuclei.

Spin structure of the neutron ({sup 3}He) and the Bjoerken sum rule

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

Meziani, Z.E.

1994-12-01

A first measurement of the longitudinal asymmetry of deep-inelastic scattering of polarized electrons from a polarized {sup 3}He target at energies ranging from 19 to 26 GeV has been performed at the Stanford Linear Accelerator Center (SLAC). The spin-structure function of the neutron g{sub 1}{sup n} has been extracted from the measured asymmetries. The Quark Parton Model (QPM) interpretation of the nucleon spin-structure function is examined in light of the new results. A test of the Ellis-Jaffe sum rule (E-J) on the neutron is performed at high momentum transfer and found to be satisfied. Furthermore, combining the proton results ofmore » the European Muon Collaboration (EMC) and the neutron results of E-142, the Bjoerken sum rule test is carried at high Q{sup 2} where higher order Perturbative Quantum Chromodynamics (PQCD) corrections and higher-twist corrections are smaller. The sum rule is saturated to within one standard deviation.« less

Spin-dependent sum rules connecting real and virtual Compton scattering verified

NASA Astrophysics Data System (ADS)

Lensky, Vadim; Pascalutsa, Vladimir; Vanderhaeghen, Marc; Kao, Chung Wen

2017-04-01

We present a detailed derivation of the two sum rules relating the spin polarizabilities measured in real, virtual, and doubly virtual Compton scattering. For example, the polarizability δL T , accessed in inclusive electron scattering, is related to the spin polarizability γE 1 E 1 and the slope of generalized polarizabilities P(M 1 ,M 1 )1-P(L 1 ,L 1 )1 , measured in, respectively, the real and the virtual Compton scattering. We verify these sum rules in different variants of chiral perturbation theory, discuss their empirical verification for the proton, and prospect their use in studies of the nucleon spin structure.

QCD sum rules study of meson-baryon sigma terms

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

Erkol, Gueray; Oka, Makoto; Turan, Guersevil

2008-11-01

The pion-baryon sigma terms and the strange-quark condensates of the octet and the decuplet baryons are calculated by employing the method of QCD sum rules. We evaluate the vacuum-to-vacuum transition matrix elements of two baryon interpolating fields in an external isoscalar-scalar field and use a Monte Carlo-based approach to systematically analyze the sum rules and the uncertainties in the results. We extract the ratios of the sigma terms, which have rather high accuracy and minimal dependence on QCD parameters. We discuss the sources of uncertainties and comment on possible strangeness content of the nucleon and the Delta.

Minimum principles in electromagnetic scattering by small aspherical particles

NASA Astrophysics Data System (ADS)

Kostinski, Alex B.; Mongkolsittisilp, Ajaree

2013-12-01

We consider the question of optimal shapes, e.g., those causing minimal extinction among all shapes of equal volume. Guided by the isoperimetric property of a sphere, relevant in the geometrical optics limit of scattering by large particles, we examine an analogous question in the low frequency approximation, seeking to disentangle electric and geometric contributions. To that end, we survey the literature on shape functionals and focus on ellipsoids, giving a simple discussion of spherical optimality for the coated ellipsoidal particle. Monotonic increase with asphericity in the low frequency regime for orientation-averaged induced dipole moments and scattering cross-sections is also shown. Additional physical insight is obtained from the Rayleigh-Gans (transparent) limit and eccentricity expansions. We propose connecting low and high frequency regimes in a single minimum principle valid for all size parameters, provided that reasonable size distributions of randomly oriented aspherical particles wash out the resonances for intermediate size parameters. This proposal is further supported by the sum rule for integrated extinction.

Decay Pattern of Pygmy States Observed in Neutron-Rich Ne26

NASA Astrophysics Data System (ADS)

Gibelin, J.; Beaumel, D.; Motobayashi, T.; Blumenfeld, Y.; Aoi, N.; Baba, H.; Elekes, Z.; Fortier, S.; Frascaria, N.; Fukuda, N.; Gomi, T.; Ishikawa, K.; Kondo, Y.; Kubo, T.; Lima, V.; Nakamura, T.; Saito, A.; Satou, Y.; Scarpaci, J.-A.; Takeshita, E.; Takeuchi, S.; Teranishi, T.; Togano, Y.; Vinodkumar, A. M.; Yanagisawa, Y.; Yoshida, K.

2008-11-01

Coulomb excitation of the exotic neutron-rich nucleus Ne26 on a Pb208 target was measured at 58MeV/u in order to search for low-lying E1 strength above the neutron emission threshold. This radioactive beam experiment was carried out at the RIKEN Accelerator Research Facility. Using the invariant mass method in the Ne25+n channel, we observe a sizable amount of E1 strength between 6 and 10 MeV excitation energy. By performing a multipole decomposition of the differential cross section, a reduced dipole transition probability of B(E1)=0.49±0.16e2fm2 is deduced, corresponding to 4.9±1.6% of the Thomas-Reiche-Kuhn sum rule. For the first time, the decay pattern of low-lying strength in a neutron-rich nucleus is measured. The extracted decay pattern is not consistent with several mean-field theory descriptions of the pygmy states.

On the generality of the mass sum rule

NASA Astrophysics Data System (ADS)

Polchinski, J.; Wise, Mark B.

1983-06-01

The sum rule, Σi(-1) 2 Ji(2 Ji+1) mi2=2 ΣaDaTr Qa, is studied to first order in supersymmetry breaking, treating the other interactions exactly. It is found to hold for spontaneous breaking and many types of explicit breaking.

An Exact Form of Lilley's Equation with a Velocity Quadrupole/Temperature Dipole Source Term

NASA Technical Reports Server (NTRS)

Goldstein, Marvin E.

2001-01-01

There have been several attempts to introduce approximations into the exact form of Lilley's equation in order to express the source term as the sum of a quadrupole whose strength is quadratic in the fluctuating velocities and a dipole whose strength is proportional to the temperature fluctuations. The purpose of this note is to show that it is possible to choose the dependent (i.e., the pressure) variable so that this type of result can be derived directly from the Euler equations without introducing any additional approximations.

Experimental evidence for an optical interference model for vibrational sum frequency generation on multilayer organic thin film systems. I. Electric dipole approximation.

PubMed

O'Brien, Daniel B; Massari, Aaron M

2015-01-14

In the field of vibrational sum frequency generation spectroscopy (VSFG) applied to organic thin film systems, a significant challenge to data analysis is in the accurate description of optical interference effects. Herein, we provide experimental evidence that a model recently developed in our lab provides an accurate description of this phenomenon. We studied the organic small molecule N,N'-dioctyl-3,4,9,10-perylenedicarboximide vapor deposited as a thickness gradient on silicon wafer substrates with two oxide thicknesses and two surface preps. VSFG data were obtained using the ssp and the sps polarization combinations in the imide carbonyl stretching region as a function of organic thickness. In this first of two reports, the data are modeled and interpreted within the ubiquitous electric dipole approximation for VSFG. The intrinsic sample responses are parameterized during the fitting routines while optical interference effects are simply calculated from the model using known refractive indices, thin film thicknesses, and beam angles. The results indicate that the thin film model provides a good description of optical interferences, indicating that interfacial terms are significant. Inconsistencies between the fitting results within the bounds of the electric dipole response motivate deliberation for additional effects to be considered in the second report.

Single-particle spectral density of the unitary Fermi gas: Novel approach based on the operator product expansion, sum rules and the maximum entropy method

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

Gubler, Philipp, E-mail: pgubler@riken.jp; RIKEN Nishina Center, Wako, Saitama 351-0198; Yamamoto, Naoki

2015-05-15

Making use of the operator product expansion, we derive a general class of sum rules for the imaginary part of the single-particle self-energy of the unitary Fermi gas. The sum rules are analyzed numerically with the help of the maximum entropy method, which allows us to extract the single-particle spectral density as a function of both energy and momentum. These spectral densities contain basic information on the properties of the unitary Fermi gas, such as the dispersion relation and the superfluid pairing gap, for which we obtain reasonable agreement with the available results based on quantum Monte-Carlo simulations.

Constraining the double gluon distribution by the single gluon distribution

DOE PAGES

Golec-Biernat, Krzysztof; Lewandowska, Emilia; Serino, Mirko; ...

2015-10-03

We show how to consistently construct initial conditions for the QCD evolution equations for double parton distribution functions in the pure gluon case. We use to momentum sum rule for this purpose and a specific form of the known single gluon distribution function in the MSTW parameterization. The resulting double gluon distribution satisfies exactly the momentum sum rule and is parameter free. Furthermore, we study numerically its evolution with a hard scale and show the approximate factorization into product of two single gluon distributions at small values of x, whereas at large values of x the factorization is always violatedmore » in agreement with the sum rule.« less

Radiation and ionization energy loss simulation for the GDH sum rule experiment in Hall-A at Jefferson Lab

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

Yan, Xin -Hu; Ye, Yun -Xiu; Chen, Jian -Ping

2015-07-17

The radiation and ionization energy loss are presented for single arm Monte Carlo simulation for the GDH sum rule experiment in Hall-A at Jefferson Lab. Radiation and ionization energy loss are discussed formore » $$^{12}C$$ elastic scattering simulation. The relative momentum ratio $$\\frac{\\Delta p}{p}$$ and $$^{12}C$$ elastic cross section are compared without and with radiation energy loss and a reasonable shape is obtained by the simulation. The total energy loss distribution is obtained, showing a Landau shape for $$^{12}C$$ elastic scattering. This simulation work will give good support for radiation correction analysis of the GDH sum rule experiment.« less

Sum rules for the uniform-background model of an atomic-sharp metal corner

NASA Astrophysics Data System (ADS)

Streitenberger, P.

1994-04-01

Analytical results are derived for the electrostatic potential of an atomic-sharp 90° metal corner in the uniform-background model. The electrostatic potential at a free jellium edge and the jellium corner, respectively, is determined exactly in terms of the energy per electron of the uniform electron gas integrated over the background density. The surface energy, the edge formation energy and the derivative of the corner formation energy with respect to the background density are given as integrals over the electrostatic potential. The present approach represents a novel approach to such sum rules, inclusive of the Budd-Vannimenus sum rules for a free jellium surface, based on general properties of linear response functions.

Photonuclear sum rules and the tetrahedral configuration of He4

NASA Astrophysics Data System (ADS)

Gazit, Doron; Barnea, Nir; Bacca, Sonia; Leidemann, Winfried; Orlandini, Giuseppina

2006-12-01

Three well-known photonuclear sum rules (SR), i.e., the Thomas-Reiche-Kuhn, the bremsstrahlungs and the polarizability SR are calculated for He4 with the realistic nucleon-nucleon potential Argonne V18 and the three-nucleon force Urbana IX. The relation between these sum rules and the corresponding energy weighted integrals of the cross section is discussed. Two additional equivalences for the bremsstrahlungs SR are given, which connect it to the proton-neutron and neutron-neutron distances. Using them, together with our result for the bremsstrahlungs SR, we find a deviation from the tetrahedral symmetry of the spatial configuration of He4. The possibility to access this deviation experimentally is discussed.

Optical oscillator strength distribution of amino acids from 3 to 250 eV and examination of the Thomas Reiche Kuhn sum rule

NASA Astrophysics Data System (ADS)

Kamohara, Masumi; Izumi, Yudai; Tanaka, Masafumi; Okamoto, Keiko; Tanaka, Masahito; Kaneko, Fusae; Kodama, Yoko; Koketsu, Toshiyuki; Nakagawa, Kazumichi

2008-10-01

Absorption spectra of thin films of glycine (Gly), alanine (Ala), valine (Val), serine (Ser), leucine (Leu), phenylalanine (Phe) and methinine (Met) were measured in absolute values of absorption cross section σ( E) for the photon energy E from 3 to 250 eV. We translated σ( E) into the optical oscillator strength distribution df/dE and we examined the Thomas-Reiche-Kuhn sum rule [Hirschfelder, J.O., Curtiss, C.F., Bird, R.B., 1954. Molecular Theory of Gases and Liquids. Wiley, New York, p. 890]. We concluded that T-R-K sum rule was correctly applicable for such relatively large size of biomolecules.

An alternative mechanism for spin-forbidden photo-ionization of diatomic molecules and its rotation-electronic selection rules

NASA Astrophysics Data System (ADS)

Chiu, Ying-Nan; Chiu, Lue-Yung Chow

1990-02-01

The spin-forbidden photo-ionization of diatomic molecules is proposed. Spin orbit interaction is invoked, resulting in the correction and mixing of the wave functions of different multiplicities. The rotation-electronic selection rules given by Dixit and McKoy (1986) for Hund's case a based on the conventional mechanism of electric dipole transition are rederived and expressed in a different format. This new format permits the generalization of the selection rules to other photoionization transitions caused by the magnetic dipole, the electric quadrupole, and the two- and three-photon operators. These selection rules, which are for transitions from one specific rotational level of a given Kronig reflection symmetry to another, will help understand rotational branching and the dynamics of interaction in the excited state. They will also help in the selective preparation of well-defined rovibronic states in resonant-enhanced multi-photon ionization processes.

Department Of Defense September 2002 Adult Poll Overview Report

DTIC Science & Technology

2003-04-01

American Poll C-17 20. Men of Honor 21. Pearl Harbor 22. Platoon 23. Rambo Series 24. Rules Of Engagement 25. Saving Private Ryan 26. Sum of...23. Rambo Series 24. Rules Of Engagement 25. Saving Private Ryan September 2002 Department of Defense Adult American Poll C-18 26. Sum of

A new approximate sum rule for bulk alloy properties

NASA Technical Reports Server (NTRS)

Bozzolo, Guillermo; Ferrante, John

1991-01-01

A new, approximate sum rule is introduced for determining bulk properties of multicomponent systems, in terms of the pure components properties. This expression is applied for the study of lattice parameters, cohesive energies, and bulk moduli of binary alloys. The correct experimental trends (i.e., departure from average values) are predicted in all cases.

On the origin independence of the Verdet tensor†

NASA Astrophysics Data System (ADS)

Caputo, M. C.; Coriani, S.; Pelloni, S.; Lazzeretti, P.

2013-07-01

The condition for invariance under a translation of the coordinate system of the Verdet tensor and the Verdet constant, calculated via quantum chemical methods using gaugeless basis sets, is expressed by a vanishing sum rule involving a third-rank polar tensor. The sum rule is, in principle, satisfied only in the ideal case of optimal variational electronic wavefunctions. In general, it is not fulfilled in non-variational calculations and variational calculations allowing for the algebraic approximation, but it can be satisfied for reasons of molecular symmetry. Group-theoretical procedures have been used to determine (i) the total number of non-vanishing components and (ii) the unique components of both the polar tensor appearing in the sum rule and the axial Verdet tensor, for a series of symmetry groups. Test calculations at the random-phase approximation level of accuracy for water, hydrogen peroxide and ammonia molecules, using basis sets of increasing quality, show a smooth convergence to zero of the sum rule. Verdet tensor components calculated for the same molecules converge to limit values, estimated via large basis sets of gaugeless Gaussian functions and London orbitals.

Renormalisation group corrections to neutrino mixing sum rules

NASA Astrophysics Data System (ADS)

Gehrlein, J.; Petcov, S. T.; Spinrath, M.; Titov, A. V.

2016-11-01

Neutrino mixing sum rules are common to a large class of models based on the (discrete) symmetry approach to lepton flavour. In this approach the neutrino mixing matrix U is assumed to have an underlying approximate symmetry form Ũν, which is dictated by, or associated with, the employed (discrete) symmetry. In such a setup the cosine of the Dirac CP-violating phase δ can be related to the three neutrino mixing angles in terms of a sum rule which depends on the symmetry form of Ũν. We consider five extensively discussed possible symmetry forms of Ũν: i) bimaximal (BM) and ii) tri-bimaximal (TBM) forms, the forms corresponding to iii) golden ratio type A (GRA) mixing, iv) golden ratio type B (GRB) mixing, and v) hexagonal (HG) mixing. For each of these forms we investigate the renormalisation group corrections to the sum rule predictions for δ in the cases of neutrino Majorana mass term generated by the Weinberg (dimension 5) operator added to i) the Standard Model, and ii) the minimal SUSY extension of the Standard Model.

Tables of Transition Probabilities and Branching Ratios for Electric Dipole Transitions Between Arbitrary Levels of Hydrogen-Like Atoms

NASA Technical Reports Server (NTRS)

Omidvar, K.

1980-01-01

Branching ratios in hydrogen-like atoms due to electric-dipole transitions are tabulated for the initial principal and angular momentum quantum number n, lambda, and final principal and angular momentum quantum numbers n, lambda. In table 1, transition probabilities are given for transitions n, lambda, yields n, where sums have been made with respect to lambda. In this table, 2 or = n' or = 10, o or = lambda' or = n'-1, and 1 or = n or = n'-1. In addition, averages with respect to lambda' and sums with respect to n, and lifetimes are given. In table 2, branching ratios are given for transitions n' lambda' yields ni, where sums have been made with respect to lambda. In these tables, 2 or = n' or = 10, 0 or = lambda', n'-1, and 1 or = n or = n'-1. Averages with respect to lambda' are also given. In table 3, branching ratios are given for transitions n' lambda' yields in lambda, where 1 or = n or = 5, 0 or = lambda or = n-1, n n' or = 15, and 0 or = lambda' or = n(s), where n(s), is the smaller of the two numbers n'-1 and 6. Averages with respect to lambda' are given.

Spontaneous light emission by atomic hydrogen: Fermi's golden rule without cheating

NASA Astrophysics Data System (ADS)

Debierre, V.; Durt, T.; Nicolet, A.; Zolla, F.

2015-10-01

Focusing on the 2 p- 1 s transition in atomic hydrogen, we investigate through first order perturbation theory the time evolution of the survival probability of an electron initially taken to be in the excited (2 p) state. We examine both the results yielded by the standard dipole approximation for the coupling between the atom and the electromagnetic field - for which we propose a cutoff-independent regularisation - and those yielded by the exact coupling function. In both cases, Fermi's golden rule is shown to be an excellent approximation for the system at hand: we found its maximal deviation from the exact behaviour of the system to be of order 10-8 /10-7. Our treatment also yields a rigorous prescription for the choice of the optimal cutoff frequency in the dipole approximation. With our cutoff, the predictions of the dipole approximation are almost indistinguishable at all times from the exact dynamics of the system.

Iso-vector form factors of the delta and nucleon in QCD sum rules

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

Ozpineci, A.

Form factors are important non-perturbative properties of hadrons. They give information about the internal structure of the hadrons. In this work, iso-vector axial-vector and iso-vector tensor form factors of the nucleon and the iso-vector axial-vector {Delta}{yields}N transition form factor calculations in QCD Sum Rules are presented.

Spectral sum rules for confining large-N theories

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

Cherman, Aleksey; McGady, David A.; Yamazaki, Masahito

2016-06-17

We consider asymptotically-free four-dimensional large-$N$ gauge theories with massive fermionic and bosonic adjoint matter fields, compactified on squashed three-spheres, and examine their regularized large-$N$ confined-phase spectral sums. The analysis is done in the limit of vanishing ’t Hooft coupling, which is justified by taking the size of the compactification manifold to be small compared to the inverse strong scale Λ ₋1. We find our results motivate us to conjecture some universal spectral sum rules for these large $N$ gauge theories.

D-Wave Heavy Baryons from QCD Sum Rules

NASA Astrophysics Data System (ADS)

Mao, Qiang; Chen, Hua-Xing; Hosaka, Atsushi; Liu, Xiang; Zhu, Shi-Lin

We study the D-wave heavy baryons using the method of QCD sum rules in the framework of heavy quark effective theory. Our results suggest that the Λc(2860), Λc(2880), Ξc(3055) and Ξc(3080) complete two D-wave SU(3) flavor 3¯F charmed baryon doublets of JP = 3/2+ and 5/2+.

Advances in QCD sum-rule calculations

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

Melikhov, Dmitri

2016-01-22

We review the recent progress in the applications of QCD sum rules to hadron properties with the emphasis on the following selected problems: (i) development of new algorithms for the extraction of ground-state parameters from two-point correlators; (ii) form factors at large momentum transfers from three-point vacuum correlation functions: (iii) properties of exotic tetraquark hadrons from correlation functions of four-quark currents.

Large-Nc sum rules for charmed baryons at subleading orders

NASA Astrophysics Data System (ADS)

Heo, Yonggoo; Lutz, Matthias F. M.

2018-05-01

Sum rules for the low-energy constants of the chiral SU(3) Lagrangian with charmed baryons of spin JP=1 /2+ and JP=3 /2+ baryons are derived from large-Nc QCD. We consider the large-Nc operator expansion at subleading orders for current-current correlation functions in the charmed baryon-ground states for two scalar and two axial-vector currents.

Beauty vector meson decay constants from QCD sum rules

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

Lucha, Wolfgang; Melikhov, Dmitri; D. V. Skobeltsyn Institute of Nuclear Physics, M. V. Lomonosov Moscow State University, 119991, Moscow

We present the outcomes of a very recent investigation of the decay constants of nonstrange and strange heavy-light beauty vector mesons, with special emphasis on the ratio of any such decay constant to the decay constant of the corresponding pseudoscalar meson, by means of Borel-transformed QCD sum rules. Our results suggest that both these ratios are below unity.

Inequalities for frequency-moment sum rules of electron liquids

NASA Technical Reports Server (NTRS)

Iwamoto, N.

1986-01-01

The relations between the various frequency-moment sum rules of electron liquids, which include even-power moments, are systematically examined by using the Cauchy-Schwarz and Hoelder inequalities. A relation involving the isothermal sound velocity and the kinetic and potential energies is obtained from one of the inequalities in the long-wavelength limit, and is generalized to arbitrary spatial dimensions.

Understanding the Interface Dipole of Copper Phthalocyanine (CuPc)/C60: Theory and Experiment.

PubMed

Sai, Na; Gearba, Raluca; Dolocan, Andrei; Tritsch, John R; Chan, Wai-Lun; Chelikowsky, James R; Leung, Kevin; Zhu, Xiaoyang

2012-08-16

Interface dipole determines the electronic energy alignment in donor/acceptor interfaces and plays an important role in organic photovoltaics. Here we present a study combining first principles density functional theory (DFT) with ultraviolet photoemission spectroscopy (UPS) and time-of-flight secondary ion mass spectrometry (TOF-SIMS) to investigate the interface dipole, energy level alignment, and structural properties at the interface between CuPc and C60. DFT finds a sizable interface dipole for the face-on orientation, in quantitative agreement with the UPS measurement, and rules out charge transfer as the origin of the interface dipole. Using TOF-SIMS, we show that the interfacial morphology for the bilayer CuPc/C60 film is characterized by molecular intermixing, containing both the face-on and the edge-on orientation. The complementary experimental and theoretical results provide both insight into the origin of the interface dipole and direct evidence for the effect of interfacial morphology on the interface dipole.

An exact sum-rule for the Hubbard model: an historical/pedagogical approach

NASA Astrophysics Data System (ADS)

Di Matteo, S.; Claveau, Y.

2017-07-01

The aim of the present article is to derive an exact integral equation for the Green function of the Hubbard model through an equation-of-motion procedure, like in the original Hubbard papers. Though our exact integral equation does not allow to solve the Hubbard model, it represents a strong constraint on its approximate solutions. An analogous sum rule has been already obtained in the literature, through the use of a spectral moment technique. We think however that our equation-of-motion procedure can be more easily related to the historical procedure of the original Hubbard papers. We also discuss examples of possible applications of the sum rule and propose and analyse a solution, fulfilling it, that can be used for a pedagogical introduction to the Mott-Hubbard metal-insulator transition.

Sum rules for zeros and intersections of Bessel functions from quantum mechanical perturbation theory

NASA Astrophysics Data System (ADS)

Pedersen, Thomas Garm

2018-07-01

Bessel functions play an important role for quantum states in spherical and cylindrical geometries. In cases of perfect confinement, the energy of Schrödinger and massless Dirac fermions is determined by the zeros and intersections of Bessel functions, respectively. In an external electric field, standard perturbation theory therefore expresses the polarizability as a sum over these zeros or intersections. Both non-relativistic and relativistic polarizabilities can be calculated analytically, however. Hence, by equating analytical expressions to perturbation expansions, several sum rules for the zeros and intersections of Bessel functions emerge.

Optimal Shape in Electromagnetic Scattering by Small Aspherical Particles

NASA Astrophysics Data System (ADS)

Kostinski, A. B.; Mongkolsittisilp, A.

2013-12-01

We consider the question of optimal shape for scattering by randomly oriented particles, e.g., shape causing minimal extinction among those of equal volume. Guided by the isoperimetric property of a sphere, relevant in the geometrical optics limit of scattering by large particles, we examine an analogous question in the low frequency (electrostatics) approximation, seeking to disentangle electric and geometric contributions. To that end, we survey the literature on shape functionals and focus on ellipsoids, giving a simple proof of spherical optimality for the coated ellipsoidal particle. Monotonic increase with asphericity in the low frequency regime for orientation-averaged induced dipole moments and scattering cross-sections is also established. Additional physical insight is obtained from the Rayleigh-Gans (transparent) limit and eccentricity expansions. We propose linking low and high frequency regime in a single minimum principle valid for all size parameters, provided that reasonable size distributions wash out the resonances for inter-mediate size parameters. This proposal is further supported by the sum rule for integrated extinction. Implications for spectro-polarimetric scattering are explicitly considered.

Evolution of the pygmy dipole resonance in Sn isotopes

NASA Astrophysics Data System (ADS)

Toft, H. K.; Larsen, A. C.; Bürger, A.; Guttormsen, M.; Görgen, A.; Nyhus, H. T.; Renstrøm, T.; Siem, S.; Tveten, G. M.; Voinov, A.

2011-04-01

Nuclear level density and γ-ray strength functions of Sn121,122 below the neutron separation energy are extracted with the Oslo method using the (He3,He3'γ) and (He3,αγ) reactions. The level densities of Sn121,122 display steplike structures, interpreted as signatures of neutron pair breaking. An enhancement in both strength functions, compared to standard models for radiative strength, is observed in our measurements for Eγ≳5.2 MeV. This enhancement is compatible with pygmy resonances centered at ≈8.4(1) and ≈8.6(2) MeV, respectively, and with integrated strengths corresponding to ≈1.8-5+1% of the classical Thomas-Reiche-Kuhn sum rule. Similar resonances were also seen in Sn116-119. Experimental neutron-capture cross reactions are well reproduced by our pygmy resonance predictions, while standard strength models are less successful. The evolution as a function of neutron number of the pygmy resonance in Sn116-122 is described as a clear increase of centroid energy from 8.0(1) to 8.6(2) MeV, but with no observable difference in integrated strengths.

Analysis of the unusual wavelength dependence of the first hyperpolarizability of porphyrin derivatives

NASA Astrophysics Data System (ADS)

De Mey, K.; Clays, K.; Therien, Michael J.; Beratan, David N.; Asselberghs, Inge

2010-08-01

Successfully predicting the frequency dispersion of electronic hyperpolarizabilities is an unresolved challenge in materials science and electronic structure theory. It has been shown1 that the generalized Thomas-Kuhn sum rules combined with linear absorption data and measured hyperpolarizabilities at one or two frequencies, may be used to predict the entire frequency-dependent electronic hyperpolarizability spectrum. This treatment includes two- and threelevel contributions that arise from the lowest two or three excited state manifolds, enabling us to describe the unusual observed frequency dispersion of the dynamic hyperpolarizability in high oscillator strength M-PZn chromophores, where (porphinato)zinc(II) (PZn) and metal(II)polypyridyl (M) units are connected via an ethyne unit that aligns the high oscillator strength transition dipoles of these components in a head-to-tail arrangement. Importantly, this approach provides a quantitative scheme to use linear optical absorption spectra and very few individual hyperpolarizability values to predict the entire frequency-dependent nonlinear optical response. In addition we provide here experimental dynamic hyperpolarizability values determined by hyper-Rayleigh scattering that underscore the validity of our approach.

Dependence of Coulomb Sum Rule on the Short Range Correlation by Using Av18 Potential

NASA Astrophysics Data System (ADS)

Modarres, M.; Moeini, H.; Moshfegh, H. R.

The Coulomb sum rule (CSR) and structure factor are calculated for inelastic electron scattering from nuclear matter at zero and finite temperature in the nonrelativistic limit. The effect of short-range correlation (SRC) is presented by using lowest order constrained variational (LOCV) method and the Argonne Av18 and Δ-Reid soft-core potentials. The effects of different potentials as well as temperature are investigated. It is found that the nonrelativistic version of Bjorken scaling approximately sets in at the momentum transfer of about 1.1 to 1.2 GeV/c and the increase of temperature makes it to decrease. While different potentials do not significantly change CSR, the SRC improves the Coulomb sum rule and we get reasonably close results to both experimental data and others theoretical predictions.

Adler Function, Bjorken Sum Rule, and the Crewther Relation to Order {alpha}{sub s}{sup 4} in a General Gauge Theory

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

Baikov, P. A.; Chetyrkin, K. G.; Kuehn, J. H.

2010-04-02

We compute, for the first time, the order {alpha}{sub s}{sup 4} contributions to the Bjorken sum rule for polarized electron-nucleon scattering and to the (nonsinglet) Adler function for the case of a generic color gauge group. We confirm at the same order a (generalized) Crewther relation which provides a strong test of the correctness of our previously obtained results: the QCD Adler function and the five-loop {beta} function in quenched QED. In particular, the appearance of an irrational contribution proportional to {zeta}{sub 3} in the latter quantity is confirmed. We obtain the commensurate scale equation relating the effective strong couplingmore » constants as inferred from the Bjorken sum rule and from the Adler function at order {alpha}{sub s}{sup 4}.« less

Predictions for the Dirac C P -violating phase from sum rules

NASA Astrophysics Data System (ADS)

Delgadillo, Luis A.; Everett, Lisa L.; Ramos, Raymundo; Stuart, Alexander J.

2018-05-01

We explore the implications of recent results relating the Dirac C P -violating phase to predicted and measured leptonic mixing angles within a standard set of theoretical scenarios in which charged lepton corrections are responsible for generating a nonzero value of the reactor mixing angle. We employ a full set of leptonic sum rules as required by the unitarity of the lepton mixing matrix, which can be reduced to predictions for the observable mixing angles and the Dirac C P -violating phase in terms of model parameters. These sum rules are investigated within a given set of theoretical scenarios for the neutrino sector diagonalization matrix for several known classes of charged lepton corrections. The results provide explicit maps of the allowed model parameter space within each given scenario and assumed form of charged lepton perturbations.

{lambda}{sub b}{yields}p, {lambda} transition form factors from QCD light-cone sum rules

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

Wang Yuming; Lue Caidian; Shen Yuelong

2009-10-01

Light-cone sum rules for the {lambda}{sub b}{yields}p, {lambda} transition form factors are derived from the correlation functions expanded by the twist of the distribution amplitudes of the {lambda}{sub b} baryon. In terms of the {lambda}{sub b} three-quark distribution amplitude models constrained by the QCD theory, we calculate the form factors at small momentum transfers and compare the results with those estimated in the conventional light-cone sum rules (LCSR) and perturbative QCD approaches. Our results indicate that the two different versions of sum rules can lead to the consistent numbers of form factors responsible for {lambda}{sub b}{yields}p transition. The {lambda}{sub b}{yields}{lambda}more » transition form factors from LCSR with the asymptotic {lambda} baryon distribution amplitudes are found to be almost 1 order larger than those obtained in the {lambda}{sub b}-baryon LCSR, implying that the preasymptotic corrections to the baryonic distribution amplitudes are of great importance. Moreover, the SU(3) symmetry breaking effects between the form factors f{sub 1}{sup {lambda}{sub b}}{sup {yields}}{sup p} and f{sub 1}{sup {lambda}{sub b}}{sup {yields}}{sup {lambda}} are computed as 28{sub -8}{sup +14}% in the framework of {lambda}{sub b}-baryon LCSR.« less

Nonlinear optical effects in a three-nanolayer metal sandwich assembly

NASA Astrophysics Data System (ADS)

Khmelinskii, Igor; Makarov, Vladimir I.

2018-04-01

We report spectral properties and frequency summing that induce superemission (SE) in sandwich structures built of Co nanolayers. We found that separate Co films with a layer thickness of 8.1, 9.2, and 11.3 nm have discrete absorption spectra, originating in transverse quantum confinement in such thin metal films. The surface plasmon resonance in this system should appear at energies over 50 000 cm-1, with its longer-wavelength tail easily observable. All of the nanolayers studied also presented discrete emission spectra, with the emission bands strongly overlapping due to large bandwidths (1500-2300 cm-1). The emission decay is described by a single-exponential function with the lifetime of 103±5 ns. Similarly, the sandwich assembly with three Co nanolayers separated by two BN nanolayers also has discrete lines in its absorption spectrum. The spectrum of the assembly is a superposition of the respective spectra of the individual Co layers. We report that the assembly can sum the pumping radiation photons, producing photons with a higher energy. This excitation summing/exciton joining effect, discovered in sandwich film systems, is reported for the first time. Exiting the two outside Co nanolayers at specific frequencies, the Co nanolayer in the middle produces the sum frequency. We identified this emission as SE, with a bandwidth of only 179±5 cm-1. This superemission band appeared with the rise time of 36±3 ns and disappeared with 73±5 ns decay time, with the estimated SE quantum yield of 0.063. We analyzed the energy transfer by the exchange mechanism in detail, although a contribution of the electric dipole-dipole mechanism could not be excluded.

Finite-width Laplace sum rules for 0-+ pseudoscalar glueball in the instanton vacuum model

NASA Astrophysics Data System (ADS)

Wang, Feng; Chen, Junlong; Liu, Jueping

2015-10-01

The correlation function of the 0-+ pseudoscalar glueball current is calculated based on the semiclassical expansion for quantum chromodynamics (QCD) in the instanton liquid background. Besides taking the pure classical contribution from instantons and the perturbative one into account, we calculate the contribution arising from the interaction (or the interference) between instantons and the quantum gluon fields, which is infrared free and more important than the pure perturbative one. Instead of the usual zero-width approximation for the resonances, the Breit-Wigner form with a correct threshold behavior for the spectral function of the finite-width resonance is adopted. The properties of the 0-+ pseudoscalar glueball are investigated via a family of the QCD Laplacian sum rules. A consistency between the subtracted and unsubtracted sum rules is very well justified. The values of the mass, decay width, and coupling constants for the 0-+ resonance in which the glueball fraction is dominant are obtained.

Renormalization group analysis of B →π form factors with B -meson light-cone sum rules

NASA Astrophysics Data System (ADS)

Shen, Yue-Long; Wei, Yan-Bing; Lü, Cai-Dian

2018-03-01

Within the framework of the B -meson light-cone sum rules, we review the calculation of radiative corrections to the three B →π transition form factors at leading power in Λ /mb. To resum large logarithmic terms, we perform the complete renormalization group evolution of the correlation function. We employ the integral transformation which diagonalizes evolution equations of the jet function and the B -meson light-cone distribution amplitude to solve these evolution equations and obtain renormalization group improved sum rules for the B →π form factors. Results of the form factors are extrapolated to the whole physical q2 region and are compared with that of other approaches. The effect of B -meson three-particle light-cone distribution amplitudes, which will contribute to the form factors at next-to-leading power in Λ /mb at tree level, is not considered in this paper.

Quantitative treatment of the solvent effects on the electronic absorption and fluorescence spectra of acridines and phenazines. The ground and first excited singlet-state dipole moments

NASA Astrophysics Data System (ADS)

Aaron, Jean Jacques; Maafi, Mounir; Párkányi, Cyril; Boniface, Christian

1995-04-01

Electronic absorption and fluorescence excitation and emission spectra of four acridines (acridine, Acridine Yellow, 9-aminoacridine and proflavine) and three phenazines (phenazine, neutral Red and safranine) are determined at room temperature (298 K) in several solvents of various polarities (dioxane, chloroform, ethyl ether, ethyl acetate, 1-butanol, 2-propanol, ethanol, methanol, dimethylformamide, acetonitrile and dimethyl sulfoxide). The effect of the solvent upon the spectral characteristics of the above compounds, is studied. In combination with the ground-state dipole moments of these compounds, the spectral data are used to evaluate their first excited singlet-state dipole moments by means of the solvatochromic shift method (Bakhshiev's and Kawski-Chamma-Viallet's correlations). The theoretical ground and excited singlet-state dipole moments for acridines and phenazines are also calculated as a vector sum of the π-component (obtained by the PPP method) and the σ-component (obtained from σ-bond moments). For most acridines and phenazines under study, the experimental excited singlet-state dipole moments are found to be higher than their ground state counterpart. The application of the Kamlet-Abboud-Taft solvatochromic parameters to the solvent effect on spectral properties of acridine and phenazine derivatives is discussed.

Multipolar and Composite Ordering in Two-Dimensional Semiclassical Geometrically Frustrated Magnets

NASA Astrophysics Data System (ADS)

Parker, Edward Temchin

Despite the success of QCD at high energies where the perturbation calculations can be carried out because of the asymptotic freedom, many fundamental questions, regarding the confinement of quarks and gluons, the nuclear forces, and the nucleon mass and structure, still remain in the non-perturbative regime. Dispersive sum rules, based on universal principles, provide a data-driven approach to study the nucleon structure without model-dependencies. Among those sum rules, the well known Gerasimov-Drell-Hearn (GDH) sum rule relates the anomalous magnetic moment to a weighted integral over the photo-absorption cross section. Its generalized form is extended for the virtual photon absorption at an arbitrary four momentum transfer square (Q2) and thus provides a unique relation to study the nucleon spin structure over an experimentally accessible range of Q2. The measured integrals can be compared with theoretical predictions for the spin dependent Compton amplitudes. Such experimental tests at intermediate and low Q 2 deepen our knowledge of the transition from the asymptotic freedom regime to the color confinement regime in QCD. Experiment E97-110 has been performed at the Thomas Jefferson National Accelerator Facility to precisely measure the generalized GDH sum rule and the moments of the neutron and 3He spin structure functions in the low energy region. During the experiment, a longitudinally-polarized electron beam with energies from 1.1 to 4.4 GeV was scattered from a 3He gas target which was polarized longitudinally or transversely at the Hall A center. Inclusive asymmetries and polarized cross-section differences, as well as the unpolarized cross sections, were measured in the quasielastic and resonance regions. In this work, the 3He spin dependent structure functions of g1(nu,Q 2) and g2(nu,Q 2) at Q2 = 0.032-0.230 GeV 2 have been extracted from the experimental data, and the generalized GDH sum rule of 3He is firstly obtained for Q 2 < 0.1 GeV2. The results exhibit a "turn-over" behavior at Q2 = 0.1 GeV2, which strongly indicates that the GDH sum rule for real photons will be recovered at Q2 → 0.

Some properties of the two-body effective interaction in the /sup 208/Pb region

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

Groleau, R.

The (/sup 3/He,d) and (/sup 4/He,t) single proton transfer reactions on /sup 208/Pb and /sup 209/Bi were studied using 30 and 40 MeV He beams from the Princeton Cyclotron Laboratory. The outgoing d and t were detected by a position sensitive proportional counter in the focal plane of a Q-3D spectrometer. The resolution varied between 10 and 14 keV (FWHM). Using the ratio of the cross-sections for the (/sup 3/He,d) and (/sup 4/He,t) reactions to determine the magnitude of the angular momentum transfers, the spectroscopic factors for the reaction on /sup 209/Bi have been measured relative to the transitions tomore » the single particle states in these reactions on /sup 208/Pb. Sum rules as developed by Bansal and French are used to study the configurations vertical bar h/sub 9/2 x h/sub 9/2/>, vertical bar h/sub 9/2/ x f/sub 7/2/>, vertical bar h/sub 9/2 x i/sub 13/2/>, vertical bar h/sub 9/2/ x f/sub 5/2/>and part of vertical bar h/sub 9/2/ x p/sub 3/2/> and vertical bar h/sub 9/2/ x p/sub 1/2>. Using the linear energy weighted sum rule, the diagonal matrix elements of the effective interaction between valence protons around the /sup 208/Pb core are deduced. The matrix elements obtained from a simple empirical interaction V/sub I//sup T=1/ of a pure Wigner type are compared to the extracted matrix elements. The interaction is characterized by an attractive short-range (0.82j and a repulsive long-range (8.2fm) potential: V/sub I//sup T = 1/ (MeV =-/96 e/sup - (r/0.82) /sup 2// + 0.51 e/sup -(r/8.2)/sup 2/. The core polarization is studied using the experimental static electric quadrupole and magnetic dipole moments of the nuclei in the /sup 208/Pb region. In general, the magnetic moments of multiple valence nucleon nuclei are well predicted by simple rules of Racah algebra. The three and four valence proton spectra (/sup 211/At and /sup 212/Rn) calculated with the experimental two particle matrix elements agree well with the experimental spectra.« less

Radiative lifetimes and cooling functions for astrophysically important molecules

NASA Astrophysics Data System (ADS)

Tennyson, Jonathan; Hulme, Kelsey; Naim, Omree K.; Yurchenko, Sergei N.

2016-02-01

Extensive line lists generated as part of the ExoMol project are used to compute lifetimes for individual rotational, rovibrational and rovibronic excited states, and temperature-dependent cooling functions by summing over all dipole-allowed transitions for the states concerned. Results are presented for SiO, CaH, AlO, ScH, H2O and methane. The results for CH4 are particularly unusual with four excited states with no dipole-allowed decay route and several others, where these decays lead to exceptionally long lifetimes. These lifetime data should be useful in models of masers and estimates of critical densities, and can provide a link with laboratory measurements. Cooling functions are important in stellar and planet formation.

78 FR 48522 - Self-Regulatory Organizations; New York Stock Exchange LLC; Notice of Filing of Proposed Rule...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-08

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L-edge sum rule analysis on 3d transition metal sites: from d10 to d0 and towards application to extremely dilute metallo-enzymes.

PubMed

Wang, Hongxin; Friedrich, Stephan; Li, Lei; Mao, Ziliang; Ge, Pinghua; Balasubramanian, Mahalingam; Patil, Daulat S

2018-03-28

According to L-edge sum rules, the number of 3d vacancies at a transition metal site is directly proportional to the integrated intensity of the L-edge X-ray absorption spectrum (XAS) for the corresponding metal complex. In this study, the numbers of 3d holes are characterized quantitatively or semi-quantitatively for a series of manganese (Mn) and nickel (Ni) complexes, including the electron configurations 3d 10 → 3d 0 . In addition, extremely dilute (<0.1% wt/wt) Ni enzymes were examined by two different approaches: (1) by using a high resolution superconducting tunnel junction X-ray detector to obtain XAS spectra with a very high signal-to-noise ratio, especially in the non-variant edge jump region; and (2) by adding an inert tracer to the sample that provides a prominent spectral feature to replace the weak edge jump for intensity normalization. In this publication, we present for the first time: (1) L-edge sum rule analysis for a series of Mn and Ni complexes that include electron configurations from an open shell 3d 0 to a closed shell 3d 10 ; (2) a systematic analysis on the uncertainties, especially on that from the edge jump, which was missing in all previous reports; (3) a clearly-resolved edge jump between pre-L 3 and post-L 2 regions from an extremely dilute sample; (4) an evaluation of an alternative normalization standard for L-edge sum rule analysis. XAS from two copper (Cu) proteins measured using a conventional semiconductor X-ray detector are also repeated as bridges between Ni complexes and dilute Ni enzymes. The differences between measuring 1% Cu enzymes and measuring <0.1% Ni enzymes are compared and discussed. This study extends L-edge sum rule analysis to virtually any 3d metal complex and any dilute biological samples that contain 3d metals.

78 FR 48513 - Self-Regulatory Organizations; NYSE MKT LLC; Notice of Filing of Proposed Rule Change To Adopt...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-08

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Higher-order electric multipole contributions to retarded non-additive three-body dispersion interaction energies between atoms: Equilateral triangle and collinear configurations

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

Salam, A., E-mail: salama@wfu.edu

2013-12-28

The theory of molecular quantum electrodynamics (QED) is used to calculate higher electric multipole contributions to the dispersion energy shift between three atoms or molecules arranged in a straight line or in an equilateral triangle configuration. As in two-body potentials, three-body dispersion interactions are viewed in the QED formalism to arise from exchange of virtual photons between coupled pairs of particles. By employing an interaction Hamiltonian that is quadratic in the electric displacement field means that third-order perturbation theory can be used to yield the energy shift for a particular combination of electric multipole polarizable species, with only six time-orderedmore » diagrams needing to be summed over. Specific potentials evaluated include dipole-dipole-quadrupole (DDQ), dipole-quadrupole-quadrupole (DQQ), and dipole-dipole-octupole (DDO) terms. For the geometries of interest, near-zone limiting forms are found to exhibit an R{sup −11} dependence on separation distance for the DDQ interaction, and an R{sup −13} behaviour for DQQ and DDO shifts, agreeing with an earlier semi-classical computation. Retardation weakens the potential in each case by R{sup −1} in the far-zone. It is found that by decomposing the octupole moment into its irreducible components of weights-1 and -3 that the former contribution to the DDO potential may be taken to be a higher-order correction to the leading triple dipole energy shift.« less

EM Transition Sum Rules Within the Framework of sdg Proton-Neutron Interacting Boson Model, Nuclear Pair Shell Model and Fermion Dynamical Symmetry Model

NASA Astrophysics Data System (ADS)

Zhao, Yumin

1997-07-01

By the techniques of the Wick theorem for coupled clusters, the no-energy-weighted electromagnetic sum-rule calculations are presented in the sdg neutron-proton interacting boson model, the nuclear pair shell model and the fermion-dynamical symmetry model. The project supported by Development Project Foundation of China, National Natural Science Foundation of China, Doctoral Education Fund of National Education Committee, Fundamental Research Fund of Southeast University

Finite-energy sum rules in eta photoproduction off a nucleon

DOE PAGES

Nys, Jannes; Mathieu, V.; Fernandez-Ramirez, Cesar; ...

2017-02-15

The reactionmore » $${\\gamma}N \\to {\\eta}N$$ is studied in the high-energy regime (with photon lab energies $$E_{\\gamma}^{\\textrm{lab}} > 4$$ GeV) using information from the resonance region through the use of finite-energy sum rules (FESR). We illustrate how analyticity allows one to map the t-dependence of the unknown Regge residue functions. As a result, we provide predictions for the energy dependence of the beam asymmetry at high energies.« less

On the loop approximation in nucleon QCD sum rules

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

Drukarev, E. G., E-mail: drukarev@thd.pnpi.spb.ru; Ryskin, M. G.; Sadovnikova, V. A.

There was a general belief that the nucleon QCD sum rules which include only the quark loops and thus contain only the condensates of dimension d = 3 and d = 4 have only a trivial solution. We demonstrate that there is also a nontrivial solution. We show that it can be treated as the lowest order approximation to the solution which includes the higher terms of the Operator Product Expansion. Inclusion of the radiative corrections improves the convergence of the series.

Aqueous solvation of polyalanine α-helices with specific water molecules and with the CPCM and SM5.2 aqueous continuum models using density functional theory.

PubMed

Marianski, Mateusz; Dannenberg, J J

2012-02-02

We present density functional theory (DFT) calculations at the X3LYP/D95(d,p) level on the solvation of polyalanine α-helices in water. The study includes the effects of discrete water molecules and the CPCM and AMSOL SM5.2 solvent continuum model both separately and in combination. We find that individual water molecules cooperatively hydrogen-bond to both the C- and N-termini of the helix, which results in increases in the dipole moment of the helix/water complex to more than the vector sum of their individual dipole moments. These waters are found to be more stable than in bulk solvent. On the other hand, individual water molecules that interact with the backbone lower the dipole moment of the helix/water complex to below that of the helix itself. Small clusters of waters at the termini increase the dipole moments of the helix/water aggregates, but the effect diminishes as more waters are added. We discuss the somewhat complex behavior of the helix with the discrete waters in the continuum models.

Aqueous Solvation of Polyalanine α-Helices with Specific Water Molecules and with the CPCM and SM5.2 Aqueous Continuum Models using Density Functional Theory

PubMed Central

Marianski, Mateusz

2012-01-01

We present density functional theory (DFT) calculations at the X3LYP/D95(d,p) level on the solvation of polyalanine α-helices in water. The study includes the effects of discrete water molecules and the CPCM and AMSOL SM5.2 solvent continuum model both separately and in combination. We find that individual water molecules cooperatively hydrogen-bond to both the C- and N-termini of the helix, which results in increases in the dipole moment of the helix/water complex to more than the vector sum of their individual dipole moments. These waters are found to be more stable than in bulk solvent. On the other hand, individual water that interact with the backbone lower the dipole moment of the helix/water complex to below that of the helix, itself. Small clusters of waters at the termini increase the dipole moments of the helix/water aggregates, but the effect diminishes as more waters are added. We discuss the somewhat complex behavior of the helix with the discrete waters in the continuum models. PMID:22201227

Effects of Dipole Perturbation on Last Good Surface of a Single Null Divertor Tokomak

NASA Astrophysics Data System (ADS)

Sharma, Yogesh; Ali, Halima; Punjabi, Alkesh

2003-10-01

Using area preserving maps developed by Punjabi and Boozer /1,2/, one is able to investigate destruction of the last good surface (LGS) under dipole perturbation. Using simple map equations: X_n+1=X_n-KYn (1-Y_n) and Y_n+1=Y_n+KX_n+1, where X_0=0, Y_0=0.99692931261 and K=0.6 for LGS. These equations with dipole perturbation equations Y_n+1=Y_n+δ s^3 fracc-X^2_n+1(X^2_n+1 + c)^2 and sum_i=0^5c_iX_n+1^i=0 are used to study the destruction of the LGS. The surface transitions from a clean, smooth curve through a stage of embedded islands of high and low density and finally to chaos. This work is supported by NASA and DOE Grant Number DE-FG02-02ER54673. This work was done under mentorship of Drs. H. Ali and A. Punjabi. 1. A. Punjabi et al Phys. Rev. Letter 69, 3322 (1992) 2. Dipole Map for Single-Null Divertor Tokamaks, A. Punjabi et al, To Appear in Phys. of Plasma (2003)

Minimal nuclear energy density functional

NASA Astrophysics Data System (ADS)

Bulgac, Aurel; Forbes, Michael McNeil; Jin, Shi; Perez, Rodrigo Navarro; Schunck, Nicolas

2018-04-01

We present a minimal nuclear energy density functional (NEDF) called "SeaLL1" that has the smallest number of possible phenomenological parameters to date. SeaLL1 is defined by seven significant phenomenological parameters, each related to a specific nuclear property. It describes the nuclear masses of even-even nuclei with a mean energy error of 0.97 MeV and a standard deviation of 1.46 MeV , two-neutron and two-proton separation energies with rms errors of 0.69 MeV and 0.59 MeV respectively, and the charge radii of 345 even-even nuclei with a mean error ɛr=0.022 fm and a standard deviation σr=0.025 fm . SeaLL1 incorporates constraints on the equation of state (EoS) of pure neutron matter from quantum Monte Carlo calculations with chiral effective field theory two-body (NN ) interactions at the next-to-next-to-next-to leading order (N3LO) level and three-body (NNN ) interactions at the next-to-next-to leading order (N2LO) level. Two of the seven parameters are related to the saturation density and the energy per particle of the homogeneous symmetric nuclear matter, one is related to the nuclear surface tension, two are related to the symmetry energy and its density dependence, one is related to the strength of the spin-orbit interaction, and one is the coupling constant of the pairing interaction. We identify additional phenomenological parameters that have little effect on ground-state properties but can be used to fine-tune features such as the Thomas-Reiche-Kuhn sum rule, the excitation energy of the giant dipole and Gamow-Teller resonances, the static dipole electric polarizability, and the neutron skin thickness.

Minimal nuclear energy density functional

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

Bulgac, Aurel; Forbes, Michael McNeil; Jin, Shi

Inmore » this paper, we present a minimal nuclear energy density functional (NEDF) called “SeaLL1” that has the smallest number of possible phenomenological parameters to date. SeaLL1 is defined by seven significant phenomenological parameters, each related to a specific nuclear property. It describes the nuclear masses of even-even nuclei with a mean energy error of 0.97 MeV and a standard deviation of 1.46 MeV , two-neutron and two-proton separation energies with rms errors of 0.69 MeV and 0.59 MeV respectively, and the charge radii of 345 even-even nuclei with a mean error ε r = 0.022 fm and a standard deviation σ r = 0.025 fm . SeaLL1 incorporates constraints on the equation of state (EoS) of pure neutron matter from quantum Monte Carlo calculations with chiral effective field theory two-body ( NN ) interactions at the next-to-next-to-next-to leading order (N3LO) level and three-body ( NNN ) interactions at the next-to-next-to leading order (N2LO) level. Two of the seven parameters are related to the saturation density and the energy per particle of the homogeneous symmetric nuclear matter, one is related to the nuclear surface tension, two are related to the symmetry energy and its density dependence, one is related to the strength of the spin-orbit interaction, and one is the coupling constant of the pairing interaction. Finally, we identify additional phenomenological parameters that have little effect on ground-state properties but can be used to fine-tune features such as the Thomas-Reiche-Kuhn sum rule, the excitation energy of the giant dipole and Gamow-Teller resonances, the static dipole electric polarizability, and the neutron skin thickness.« less

Minimal nuclear energy density functional

DOE PAGES

Bulgac, Aurel; Forbes, Michael McNeil; Jin, Shi; ...

2018-04-17

Inmore » this paper, we present a minimal nuclear energy density functional (NEDF) called “SeaLL1” that has the smallest number of possible phenomenological parameters to date. SeaLL1 is defined by seven significant phenomenological parameters, each related to a specific nuclear property. It describes the nuclear masses of even-even nuclei with a mean energy error of 0.97 MeV and a standard deviation of 1.46 MeV , two-neutron and two-proton separation energies with rms errors of 0.69 MeV and 0.59 MeV respectively, and the charge radii of 345 even-even nuclei with a mean error ε r = 0.022 fm and a standard deviation σ r = 0.025 fm . SeaLL1 incorporates constraints on the equation of state (EoS) of pure neutron matter from quantum Monte Carlo calculations with chiral effective field theory two-body ( NN ) interactions at the next-to-next-to-next-to leading order (N3LO) level and three-body ( NNN ) interactions at the next-to-next-to leading order (N2LO) level. Two of the seven parameters are related to the saturation density and the energy per particle of the homogeneous symmetric nuclear matter, one is related to the nuclear surface tension, two are related to the symmetry energy and its density dependence, one is related to the strength of the spin-orbit interaction, and one is the coupling constant of the pairing interaction. Finally, we identify additional phenomenological parameters that have little effect on ground-state properties but can be used to fine-tune features such as the Thomas-Reiche-Kuhn sum rule, the excitation energy of the giant dipole and Gamow-Teller resonances, the static dipole electric polarizability, and the neutron skin thickness.« less

Nuclear Deformation and Neutron Excess as Competing Effects for Dipole Strength in the Pygmy Region

NASA Astrophysics Data System (ADS)

Massarczyk, R.; Schwengner, R.; Dönau, F.; Frauendorf, S.; Anders, M.; Bemmerer, D.; Beyer, R.; Bhatia, C.; Birgersson, E.; Butterling, M.; Elekes, Z.; Ferrari, A.; Gooden, M. E.; Hannaske, R.; Junghans, A. R.; Kempe, M.; Kelley, J. H.; Kögler, T.; Matic, A.; Menzel, M. L.; Müller, S.; Reinhardt, T. P.; Röder, M.; Rusev, G.; Schilling, K. D.; Schmidt, K.; Schramm, G.; Tonchev, A. P.; Tornow, W.; Wagner, A.

2014-02-01

The electromagnetic dipole strength below the neutron-separation energy has been studied for the xenon isotopes with mass numbers A =124, 128, 132, and 134 in nuclear resonance fluorescence experiments using the γELBE bremsstrahlung facility at Helmholtz-Zentrum Dresden-Rossendorf and the HIγS facility at Triangle Universities Nuclear Laboratory Durham. The systematic study gained new information about the influence of the neutron excess as well as of nuclear deformation on the strength in the region of the pygmy dipole resonance. The results are compared with those obtained for the chain of molybdenum isotopes and with predictions of a random-phase approximation in a deformed basis. It turned out that the effect of nuclear deformation plays a minor role compared with the one caused by neutron excess. A global parametrization of the strength in terms of neutron and proton numbers allowed us to derive a formula capable of predicting the summed E1 strengths in the pygmy region for a wide mass range of nuclides.

Nuclear deformation and neutron excess as competing effects for dipole strength in the pygmy region.

PubMed

Massarczyk, R; Schwengner, R; Dönau, F; Frauendorf, S; Anders, M; Bemmerer, D; Beyer, R; Bhatia, C; Birgersson, E; Butterling, M; Elekes, Z; Ferrari, A; Gooden, M E; Hannaske, R; Junghans, A R; Kempe, M; Kelley, J H; Kögler, T; Matic, A; Menzel, M L; Müller, S; Reinhardt, T P; Röder, M; Rusev, G; Schilling, K D; Schmidt, K; Schramm, G; Tonchev, A P; Tornow, W; Wagner, A

2014-02-21

The electromagnetic dipole strength below the neutron-separation energy has been studied for the xenon isotopes with mass numbers A=124, 128, 132, and 134 in nuclear resonance fluorescence experiments using the γELBE bremsstrahlung facility at Helmholtz-Zentrum Dresden-Rossendorf and the HIγS facility at Triangle Universities Nuclear Laboratory Durham. The systematic study gained new information about the influence of the neutron excess as well as of nuclear deformation on the strength in the region of the pygmy dipole resonance. The results are compared with those obtained for the chain of molybdenum isotopes and with predictions of a random-phase approximation in a deformed basis. It turned out that the effect of nuclear deformation plays a minor role compared with the one caused by neutron excess. A global parametrization of the strength in terms of neutron and proton numbers allowed us to derive a formula capable of predicting the summed E1 strengths in the pygmy region for a wide mass range of nuclides.

OPE, charm-quark mass, and decay constants of D and Ds mesons from QCD sum rules

PubMed Central

Lucha, Wolfgang; Melikhov, Dmitri; Simula, Silvano

2011-01-01

We present a sum-rule extraction of the decay constants of the charmed mesons D and Ds from the two-point correlator of pseudoscalar currents. First, we compare the perturbative expansion for the correlator and the decay constant performed in terms of the pole and the running MS¯ masses of the charm quark. The perturbative expansion in terms of the pole mass shows no signs of convergence whereas reorganizing this very expansion in terms of the MS¯ mass leads to a distinct hierarchy of the perturbative expansion. Furthermore, the decay constants extracted from the pole-mass correlator turn out to be considerably smaller than those obtained by means of the MS¯-mass correlator. Second, making use of the OPE in terms of the MS¯ mass, we determine the decay constants of both D and Ds mesons with an emphasis on the uncertainties in these quantities related both to the input QCD parameters and to the limited accuracy of the method of sum rules. PMID:21949465

Radiative corrections to the solar lepton mixing sum rule

NASA Astrophysics Data System (ADS)

Zhang, Jue; Zhou, Shun

2016-08-01

The simple correlation among three lepton flavor mixing angles ( θ 12, θ 13, θ 23) and the leptonic Dirac CP-violating phase δ is conventionally called a sum rule of lepton flavor mixing, which may be derived from a class of neutrino mass models with flavor symmetries. In this paper, we consider the solar lepton mixing sum rule θ 12 ≈ θ 12 ν + θ 13 cos δ, where θ 12 ν stems from a constant mixing pattern in the neutrino sector and takes the value of θ 12 ν = 45 ° for the bi-maximal mixing (BM), {θ}_{12}^{ν } = { tan}^{-1}(1/√{2}) ≈ 35.3° for the tri-bimaximal mixing (TBM) or {θ}_{12}^{ν } = { tan}^{-1}(1/√{5+1}) ≈ 31.7° for the golden-ratio mixing (GR), and investigate the renormalization-group (RG) running effects on lepton flavor mixing parameters when this sum rule is assumed at a superhigh-energy scale. For illustration, we work within the framework of the minimal supersymmetric standard model (MSSM), and implement the Bayesian approach to explore the posterior distribution of δ at the low-energy scale, which becomes quite broad when the RG running effects are significant. Moreover, we also discuss the compatibility of the above three mixing scenarios with current neutrino oscillation data, and observe that radiative corrections can increase such a compatibility for the BM scenario, resulting in a weaker preference for the TBM and GR ones.

Influence of the photon orbital angular momentum on electric dipole transitions: negative experimental evidence.

PubMed

Giammanco, F; Perona, A; Marsili, P; Conti, F; Fidecaro, F; Gozzini, S; Lucchesini, A

2017-01-15

We describe an experiment of atomic spectroscopy devoted to ascertaining whether the orbital angular momentum (OAM) of photons has the same property of interacting with atoms or molecules as occurs for the spin angular momentum (SAM). In our experiment, rubidium vapors are excited by means of laser radiation with different combinations of OAM and SAM, particularly selected to inhibit or enhance the fluorescence according to the selection rules for the electric dipole transitions between the fundamental state and the first excited doublet. Our results clearly show that an electric-dipole-type transition is insensitive to the OAM value, and provide an original validation of a problem long debated in theoretical works.

First-Principles Framework to Compute Sum-Frequency Generation Vibrational Spectra of Semiconductors and Insulators.

PubMed

Wan, Quan; Galli, Giulia

2015-12-11

We present a first-principles framework to compute sum-frequency generation (SFG) vibrational spectra of semiconductors and insulators. The method is based on density functional theory and the use of maximally localized Wannier functions to compute the response to electric fields, and it includes the effect of electric field gradients at surfaces. In addition, it includes quadrupole contributions to SFG spectra, thus enabling the verification of the dipole approximation, whose validity determines the surface specificity of SFG spectroscopy. We compute the SFG spectra of ice I_{h} basal surfaces and identify which spectra components are affected by bulk contributions. Our results are in good agreement with experiments at low temperature.

Mrst '96: Current Ideas in Theoretical Physics - Proceedings of the Eighteenth Annual Montréal-Rochester-Syracuse-Toronto Meeting

NASA Astrophysics Data System (ADS)

O'Donnell, Patrick J.; Smith, Brian Hendee

1996-11-01

The Table of Contents for the full book PDF is as follows: * Preface * Roberto Mendel, An Appreciaton * The Infamous Coulomb Gauge * Renormalized Path Integral in Quantum Mechanics * New Analysis of the Divergence of Perturbation Theory * The Last of the Soluble Two Dimensional Field Theories? * Rb and Heavy Quark Mixing * Rb Problem: Loop Contributions and Supersymmetry * QCD Radiative Effects in Inclusive Hadronic B Decays * CP-Violating Dipole Moments of Quarks in the Kobayashi-Maskawa Model * Hints of Dynamical Symmetry Breaking? * Pi Pi Scattering in an Effective Chiral Lagrangian * Pion-Resonance Parameters from QCD Sum Rules * Higgs Theorem, Effective Action, and its Gauge Invariance * SUSY and the Decay H_2^0 to gg * Effective Higgs-to-Light Quark Coupling Induced by Heavy Quark Loops * Heavy Charged Lepton Production in Superstring Inspired E6 Models * The Elastic Properties of a Flat Crystalline Membrane * Gauge Dependence of Topological Observables in Chern-Simons Theory * Entanglement Entropy From Edge States * A Simple General Treatment of Flavor Oscillations * From Schrödinger to Maupertuis: Least Action Principles from Quantum Mechanics * The Matrix Method for Multi-Loop Feynman Integrals * Simplification in QCD and Electroweak Calculations * Programme * List of Participants

He3 Spin-Dependent Cross Sections and Sum Rules

NASA Astrophysics Data System (ADS)

Slifer, K.; Amarian, M.; Auerbach, L.; Averett, T.; Berthot, J.; Bertin, P.; Bertozzi, B.; Black, T.; Brash, E.; Brown, D.; Burtin, E.; Calarco, J.; Cates, G.; Chai, Z.; Chen, J.-P.; Choi, Seonho; Chudakov, E.; Ciofi Degli Atti, C.; Cisbani, E.; de Jager, C. W.; Deur, A.; Disalvo, R.; Dieterich, S.; Djawotho, P.; Finn, M.; Fissum, K.; Fonvieille, H.; Frullani, S.; Gao, H.; Gao, J.; Garibaldi, F.; Gasparian, A.; Gilad, S.; Gilman, R.; Glamazdin, A.; Glashausser, C.; Glöckle, W.; Golak, J.; Goldberg, E.; Gomez, J.; Gorbenko, V.; Hansen, J.-O.; Hersman, B.; Holmes, R.; Huber, G. M.; Hughes, E.; Humensky, B.; Incerti, S.; Iodice, M.; Jensen, S.; Jiang, X.; Jones, C.; Jones, G.; Jones, M.; Jutier, C.; Kamada, H.; Ketikyan, A.; Kominis, I.; Korsch, W.; Kramer, K.; Kumar, K.; Kumbartzki, G.; Kuss, M.; Lakuriqi, E.; Laveissiere, G.; Lerose, J. J.; Liang, M.; Liyanage, N.; Lolos, G.; Malov, S.; Marroncle, J.; McCormick, K.; McKeown, R. D.; Meziani, Z.-E.; Michaels, R.; Mitchell, J.; Nogga, A.; Pace, E.; Papandreou, Z.; Pavlin, T.; Petratos, G. G.; Pripstein, D.; Prout, D.; Ransome, R.; Roblin, Y.; Rowntree, D.; Rvachev, M.; Sabatié, F.; Saha, A.; Salmè, G.; Scopetta, S.; Skibiński, R.; Souder, P.; Saito, T.; Strauch, S.; Suleiman, R.; Takahashi, K.; Teijiro, S.; Todor, L.; Tsubota, H.; Ueno, H.; Urciuoli, G.; van der Meer, R.; Vernin, P.; Voskanian, H.; Witała, H.; Wojtsekhowski, B.; Xiong, F.; Xu, W.; Yang, J.-C.; Zhang, B.; Zolnierczuk, P.

2008-07-01

We present a measurement of the spin-dependent cross sections for the He→3(e→,e')X reaction in the quasielastic and resonance regions at a four-momentum transfer 0.1≤Q2≤0.9GeV2. The spin-structure functions have been extracted and used to evaluate the nuclear Burkhardt-Cottingham and extended Gerasimov-Drell-Hearn sum rules for the first time. The data are also compared to an impulse approximation calculation and an exact three-body Faddeev calculation in the quasielastic region.

The magnetic moment of the Z_c(3900) as an axialvector tetraquark state with QCD sum rules

NASA Astrophysics Data System (ADS)

Wang, Zhi-Gang

2018-04-01

In this article, we assign the Z_c^± (3900) to be the diquark-antidiquark type axialvector tetraquark state, study its magnetic moment with the QCD sum rules in the external weak electromagnetic field by carrying out the operator product expansion up to the vacuum condensates of dimension 8. We pay special attention to matching the hadron side with the QCD side of the correlation function to obtain solid duality, the routine can be applied to study other electromagnetic properties of the exotic particles.

Boundary qKZ equation and generalized Razumov Stroganov sum rules for open IRF models

NASA Astrophysics Data System (ADS)

Di Francesco, P.

2005-11-01

We find higher-rank generalizations of the Razumov-Stroganov sum rules at q = -ei π/(k+1) for Ak-1 models with open boundaries, by constructing polynomial solutions of level-1 boundary quantum Knizhnik-Zamolodchikov equations for U_q(\\frak {sl}(k)) . The result takes the form of a character of the symplectic group, that leads to a generalization of the number of vertically symmetric alternating sign matrices. We also investigate the other combinatorial point q = -1, presumably related to the geometry of nilpotent matrix varieties.

Monopole and dipole estimation for multi-frequency sky maps by linear regression

NASA Astrophysics Data System (ADS)

Wehus, I. K.; Fuskeland, U.; Eriksen, H. K.; Banday, A. J.; Dickinson, C.; Ghosh, T.; Górski, K. M.; Lawrence, C. R.; Leahy, J. P.; Maino, D.; Reich, P.; Reich, W.

2017-01-01

We describe a simple but efficient method for deriving a consistent set of monopole and dipole corrections for multi-frequency sky map data sets, allowing robust parametric component separation with the same data set. The computational core of this method is linear regression between pairs of frequency maps, often called T-T plots. Individual contributions from monopole and dipole terms are determined by performing the regression locally in patches on the sky, while the degeneracy between different frequencies is lifted whenever the dominant foreground component exhibits a significant spatial spectral index variation. Based on this method, we present two different, but each internally consistent, sets of monopole and dipole coefficients for the nine-year WMAP, Planck 2013, SFD 100 μm, Haslam 408 MHz and Reich & Reich 1420 MHz maps. The two sets have been derived with different analysis assumptions and data selection, and provide an estimate of residual systematic uncertainties. In general, our values are in good agreement with previously published results. Among the most notable results are a relative dipole between the WMAP and Planck experiments of 10-15μK (depending on frequency), an estimate of the 408 MHz map monopole of 8.9 ± 1.3 K, and a non-zero dipole in the 1420 MHz map of 0.15 ± 0.03 K pointing towards Galactic coordinates (l,b) = (308°,-36°) ± 14°. These values represent the sum of any instrumental and data processing offsets, as well as any Galactic or extra-Galactic component that is spectrally uniform over the full sky.

Applicability of the single equivalent point dipole model to represent a spatially distributed bio-electrical source

NASA Technical Reports Server (NTRS)

Armoundas, A. A.; Feldman, A. B.; Sherman, D. A.; Cohen, R. J.

2001-01-01

Although the single equivalent point dipole model has been used to represent well-localised bio-electrical sources, in realistic situations the source is distributed. Consequently, position estimates of point dipoles determined by inverse algorithms suffer from systematic error due to the non-exact applicability of the inverse model. In realistic situations, this systematic error cannot be avoided, a limitation that is independent of the complexity of the torso model used. This study quantitatively investigates the intrinsic limitations in the assignment of a location to the equivalent dipole due to distributed electrical source. To simulate arrhythmic activity in the heart, a model of a wave of depolarisation spreading from a focal source over the surface of a spherical shell is used. The activity is represented by a sequence of concentric belt sources (obtained by slicing the shell with a sequence of parallel plane pairs), with constant dipole moment per unit length (circumferentially) directed parallel to the propagation direction. The distributed source is represented by N dipoles at equal arc lengths along the belt. The sum of the dipole potentials is calculated at predefined electrode locations. The inverse problem involves finding a single equivalent point dipole that best reproduces the electrode potentials due to the distributed source. The inverse problem is implemented by minimising the chi2 per degree of freedom. It is found that the trajectory traced by the equivalent dipole is sensitive to the location of the spherical shell relative to the fixed electrodes. It is shown that this trajectory does not coincide with the sequence of geometrical centres of the consecutive belt sources. For distributed sources within a bounded spherical medium, displaced from the sphere's centre by 40% of the sphere's radius, it is found that the error in the equivalent dipole location varies from 3 to 20% for sources with size between 5 and 50% of the sphere's radius. Finally, a method is devised to obtain the size of the distributed source during the cardiac cycle.

L-edge sum rule analysis on 3d transition metal sites: from d 10 to d 0 and towards application to extremely dilute metallo-enzymes

DOE PAGES

Wang, Hongxin; Friedrich, Stephan; Li, Lei; ...

2018-02-13

According to L-edge sum rules, the number of 3d vacancies at a transition metal site is directly proportional to the integrated intensity of the L-edge X-ray absorption spectrum (XAS) for the corresponding metal complex. In this study, the numbers of 3d holes are characterized quantitatively or semi-quantitatively for a series of manganese (Mn) and nickel (Ni) complexes, including the electron configurations 3d 10 → 3d 0. In addition, extremely dilute (<0.1% wt/wt) Ni enzymes were examined by two different approaches: (1) by using a high resolution superconducting tunnel junction X-ray detector to obtain XAS spectra with a very high signal-to-noisemore » ratio, especially in the non-variant edge jump region; and (2) by adding an inert tracer to the sample that provides a prominent spectral feature to replace the weak edge jump for intensity normalization. In this publication, we present for the first time: (1) L-edge sum rule analysis for a series of Mn and Ni complexes that include electron configurations from an open shell 3d0 to a closed shell 3d 10; (2) a systematic analysis on the uncertainties, especially on that from the edge jump, which was missing in all previous reports; (3) a clearly-resolved edge jump between pre-L 3 and post-L 2 regions from an extremely dilute sample; (4) an evaluation of an alternative normalization standard for L-edge sum rule analysis. XAS from two copper (Cu) proteins measured using a conventional semiconductor X-ray detector are also repeated as bridges between Ni complexes and dilute Ni enzymes. The differences between measuring 1% Cu enzymes and measuring <0.1% Ni enzymes are compared and discussed. As a result, this study extends L-edge sum rule analysis to virtually any 3d metal complex and any dilute biological samples that contain 3d metals.« less

L-edge sum rule analysis on 3d transition metal sites: from d 10 to d 0 and towards application to extremely dilute metallo-enzymes

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

Wang, Hongxin; Friedrich, Stephan; Li, Lei

According to L-edge sum rules, the number of 3d vacancies at a transition metal site is directly proportional to the integrated intensity of the L-edge X-ray absorption spectrum (XAS) for the corresponding metal complex. In this study, the numbers of 3d holes are characterized quantitatively or semi-quantitatively for a series of manganese (Mn) and nickel (Ni) complexes, including the electron configurations 3d 10 → 3d 0. In addition, extremely dilute (<0.1% wt/wt) Ni enzymes were examined by two different approaches: (1) by using a high resolution superconducting tunnel junction X-ray detector to obtain XAS spectra with a very high signal-to-noisemore » ratio, especially in the non-variant edge jump region; and (2) by adding an inert tracer to the sample that provides a prominent spectral feature to replace the weak edge jump for intensity normalization. In this publication, we present for the first time: (1) L-edge sum rule analysis for a series of Mn and Ni complexes that include electron configurations from an open shell 3d0 to a closed shell 3d 10; (2) a systematic analysis on the uncertainties, especially on that from the edge jump, which was missing in all previous reports; (3) a clearly-resolved edge jump between pre-L 3 and post-L 2 regions from an extremely dilute sample; (4) an evaluation of an alternative normalization standard for L-edge sum rule analysis. XAS from two copper (Cu) proteins measured using a conventional semiconductor X-ray detector are also repeated as bridges between Ni complexes and dilute Ni enzymes. The differences between measuring 1% Cu enzymes and measuring <0.1% Ni enzymes are compared and discussed. As a result, this study extends L-edge sum rule analysis to virtually any 3d metal complex and any dilute biological samples that contain 3d metals.« less

Fusion of classifiers for REIS-based detection of suspicious breast lesions

NASA Astrophysics Data System (ADS)

Lederman, Dror; Wang, Xingwei; Zheng, Bin; Sumkin, Jules H.; Tublin, Mitchell; Gur, David

2011-03-01

After developing a multi-probe resonance-frequency electrical impedance spectroscopy (REIS) system aimed at detecting women with breast abnormalities that may indicate a developing breast cancer, we have been conducting a prospective clinical study to explore the feasibility of applying this REIS system to classify younger women (< 50 years old) into two groups of "higher-than-average risk" and "average risk" of having or developing breast cancer. The system comprises one central probe placed in contact with the nipple, and six additional probes uniformly distributed along an outside circle to be placed in contact with six points on the outer breast skin surface. In this preliminary study, we selected an initial set of 174 examinations on participants that have completed REIS examinations and have clinical status verification. Among these, 66 examinations were recommended for biopsy due to findings of a highly suspicious breast lesion ("positives"), and 108 were determined as negative during imaging based procedures ("negatives"). A set of REIS-based features, extracted using a mirror-matched approach, was computed and fed into five machine learning classifiers. A genetic algorithm was used to select an optimal subset of features for each of the five classifiers. Three fusion rules, namely sum rule, weighted sum rule and weighted median rule, were used to combine the results of the classifiers. Performance evaluation was performed using a leave-one-case-out cross-validation method. The results indicated that REIS may provide a new technology to identify younger women with higher than average risk of having or developing breast cancer. Furthermore, it was shown that fusion rule, such as a weighted median fusion rule and a weighted sum fusion rule may improve performance as compared with the highest performing single classifier.

Scissors Modes and Spin Excitations in Light Nuclei Including ΔN=2 Excitations: Behaviour of 8Be and 10Be

NASA Astrophysics Data System (ADS)

Fayache, M. S.; Sharma, S. Shelley; Zamick, L.

1996-10-01

Shell model calculations are performed for magnetic dipole excitations in8Be and10Be, first with a quadrupole-quadrupole interaction (Q·Q) and then with a realistic interaction. The calculations are performed both in a 0pspace and in a large space which includes all 2ℏωexcitations. In the 0pwithQ·Qwe have an analytic expression for the energies of all states. In this limit we find that in10Be theL=1S=0 scissors mode with isospinT=1 is degenerate with that ofT=2. By projection from an intrinsic state we can obtain simple expressions forB(M1) to the scissors modes in8Be and10Be. We plot cumulative sums for energy-weighted isovector orbital transitions fromJ=0+ground states to the 1+excited states. These have the structure of a low-energy plateau and a steep rise to a high-energy plateau. The relative magnitudes of these plateaux are discussed. By comparing8Be and10Be we find that contrary to the behaviour in heavy deformed nuclei,B(M1)orbitalis not proportional toB(E2). On the other hand, a sum rule which relatesB(M1) to the difference (B(E2)isoscalar-B(E2)isovector) succeeds in describing the difference in behaviours in the two nuclei. The results forQ·Qand the realistic interactions are compared, as are the results in the 0pspace and the large (0p+2ℏω) space. The Wigner supermultiplet scheme is a very useful guide in analyzing the shell model results.

New a1(1420 ) state: Structure, mass, and width

NASA Astrophysics Data System (ADS)

Sundu, H.; Agaev, S. S.; Azizi, K.

2018-03-01

The structure, spectroscopic parameters and width of the resonance with quantum numbers JP C=1++ discovered by the COMPASS Collaboration and classified as the a1(1420 ) meson are examined in the context of QCD sum rule method. In the calculations the axial-vector meson a1(1420 ) is treated as a four-quark state with the diquark-antidiquark structure. The mass and current coupling of a1(1420 ) are evaluated using QCD two-point sum rule approach. Its observed decay mode a1(1420 )→f0(980 )π , and kinematically allowed ones, namely a1→K*±K∓ , a1→K*0K¯ 0 and a1→K¯ *0K0 channels are studied employing QCD sum rules on the light-cone. Our prediction for the mass of the a1(1420 ) state ma1=1416-79+81 MeV is in excellent agreement with the experimental result. Width of this state Γ =145.52 ±20.79 MeV within theoretical and experimental errors is also in accord with the COMPASS data.

Lattice input on the inclusive flavor-breaking τ Vus puzzle

NASA Astrophysics Data System (ADS)

Maltman, Kim; Hudspith, Renwick; Lewis, Randy; Wolfe, Carl; Zanotti, James

2015-10-01

Recent versions of the standard approach to implementing the flavor-breaking finite-energy sum rule determination of Vus using spectral data obtained from hadronic tau decays produce values of Vus more than 3 sigma low relative to the expectations of 3-family unitarity. We revisit this problem, focusing on systematic issues in the treatment of OPE contributions, employing lattice data for the relevant flavor-breaking correlator combinination to help in understanding how to treat the slowly converging D = 2 series and investigate potential D > 4 non-perturbative contributions. The results, in combination with observations from additional flavor-breaking continuum sum rules, are shown to suggest an alternate implementation of the flavor-breaking sum rule approach. This alternate analysis approach is shown to produce significantly higher Vus than obtained using the assumptions of the conventional implementation, for reasons that will be explained in detail. We also show that, when this approach is implemented using new preliminary results for the tau K pi branching fractions, the Vus obtained is in excellent agreement with that obtained from recent analyses of Kell3 using lattice input for f+(0).

Exact Fundamental Limits of the First and Second Hyperpolarizabilities

NASA Astrophysics Data System (ADS)

Lytel, Rick; Mossman, Sean; Crowell, Ethan; Kuzyk, Mark G.

2017-08-01

Nonlinear optical interactions of light with materials originate in the microscopic response of the molecular constituents to excitation by an optical field, and are expressed by the first (β ) and second (γ ) hyperpolarizabilities. Upper bounds to these quantities were derived seventeen years ago using approximate, truncated state models that violated completeness and unitarity, and far exceed those achieved by potential optimization of analytical systems. This Letter determines the fundamental limits of the first and second hyperpolarizability tensors using Monte Carlo sampling of energy spectra and transition moments constrained by the diagonal Thomas-Reiche-Kuhn (TRK) sum rules and filtered by the off-diagonal TRK sum rules. The upper bounds of β and γ are determined from these quantities by applying error-refined extrapolation to perfect compliance with the sum rules. The method yields the largest diagonal component of the hyperpolarizabilities for an arbitrary number of interacting electrons in any number of dimensions. The new method provides design insight to the synthetic chemist and nanophysicist for approaching the limits. This analysis also reveals that the special cases which lead to divergent nonlinearities in the many-state catastrophe are not physically realizable.

Longitudinal and bulk viscosities of Lennard-Jones fluids

NASA Astrophysics Data System (ADS)

Tankeshwar, K.; Pathak, K. N.; Ranganathan, S.

1996-12-01

Expressions for the longitudinal and bulk viscosities have been derived using Green Kubo formulae involving the time integral of the longitudinal and bulk stress autocorrelation functions. The time evolution of stress autocorrelation functions are determined using the Mori formalism and a memory function which is obtained from the Mori equation of motion. The memory function is of hyperbolic secant form and involves two parameters which are related to the microscopic sum rules of the respective autocorrelation function. We have derived expressions for the zeroth-, second-and fourth- order sum rules of the longitudinal and bulk stress autocorrelation functions. These involve static correlation functions up to four particles. The final expressions for these have been put in a form suitable for numerical calculations using low- order decoupling approximations. The numerical results have been obtained for the sum rules of longitudinal and bulk stress autocorrelation functions. These have been used to calculate the longitudinal and bulk viscosities and time evolution of the longitudinal stress autocorrelation function of the Lennard-Jones fluids over wide ranges of densities and temperatures. We have compared our results with the available computer simulation data and found reasonable agreement.

MOLSIM: A modular molecular simulation software

PubMed Central

Jurij, Reščič

2015-01-01

The modular software MOLSIM for all‐atom molecular and coarse‐grained simulations is presented with focus on the underlying concepts used. The software possesses four unique features: (1) it is an integrated software for molecular dynamic, Monte Carlo, and Brownian dynamics simulations; (2) simulated objects are constructed in a hierarchical fashion representing atoms, rigid molecules and colloids, flexible chains, hierarchical polymers, and cross‐linked networks; (3) long‐range interactions involving charges, dipoles and/or anisotropic dipole polarizabilities are handled either with the standard Ewald sum, the smooth particle mesh Ewald sum, or the reaction‐field technique; (4) statistical uncertainties are provided for all calculated observables. In addition, MOLSIM supports various statistical ensembles, and several types of simulation cells and boundary conditions are available. Intermolecular interactions comprise tabulated pairwise potentials for speed and uniformity and many‐body interactions involve anisotropic polarizabilities. Intramolecular interactions include bond, angle, and crosslink potentials. A very large set of analyses of static and dynamic properties is provided. The capability of MOLSIM can be extended by user‐providing routines controlling, for example, start conditions, intermolecular potentials, and analyses. An extensive set of case studies in the field of soft matter is presented covering colloids, polymers, and crosslinked networks. © 2015 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc. PMID:25994597

Why do we need three levels to understand the molecular optical response?

NASA Astrophysics Data System (ADS)

Perez-Moreno, Javier; Clays, Koen; Kuzyk, Mark G.

2011-10-01

Traditionally, the nonlinear optical response at the molecular level has been modeled using the two-level approximation, under the assumption that the behavior of the exact sum-over-states (SOS) expressions for the molecular polarizabilities is well represented by the contribution of only two levels. We show how, a rigorous application of the Thomas-Kuhn sum-rules over the SOS expression for the diagonal component of the first-hyperpolarziability proves that the two-level approximation is unphysical. In addition, we indicate how the contributions of potentially infinite number of states to the SOS expressions for the first-hyperpolarizability are well represented by the contributions of a generic three-level system. This explains why the analysis of the three-level model in conjugation with the sum rules has lead to successful paradigms for the optimization of organic chromophores.

High-frequency sum rules for the quasi-one-dimensional quantum plasma dielectric tensor

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

Genga, R.O.

A high-frequency sum-rule expansion is derived for all elements of the spinless quasi-one-dimensional quantum plasma response tensor at T = 0 K. As in the magnetized classical plasmas, we find that Omega/sub 4//sup 13/ is the only coefficient of omega/sup -4/ that has no correlational term. Further, we find that the correlations either enhance or reduce the negative quantum dispersion, depending on the direction of propagation. It is also noted that the quantum effect does not exist for the ordinary and the extraordinary modes for perpendicular and parallel propagation, respectively.

Numerical evaluation of electromagnetic fields due to dipole antennas in the presence of stratified media

NASA Technical Reports Server (NTRS)

Tsang, L.; Brown, R.; Kong, J. A.; Simmons, G.

1974-01-01

Two numerical methods are used to evaluate the integrals that express the em fields due to dipole antennas radiating in the presence of a stratified medium. The first method is a direct integration by means of Simpson's rule. The second method is indirect and approximates the kernel of the integral by means of the fast Fourier transform. In contrast to previous analytical methods that applied only to two-layer cases the numerical methods can be used for any arbitrary number of layers with general properties.

76 FR 9939 - Garnishment of Accounts Containing Federal Benefit Payments

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-23

... rule establishes procedures that financial institutions must follow when they receive a garnishment.... The rule requires financial institutions that receive such a garnishment order to determine the sum of... organizations, legal services organizations, financial institutions and their trade associations, State...

Entanglement sum rules.

PubMed

Swingle, Brian

2013-09-06

We compute the entanglement entropy of a wide class of models that may be characterized as describing matter coupled to gauge fields. Our principle result is an entanglement sum rule that states that the entropy of the full system is the sum of the entropies of the two components. In the context of the models we consider, this result applies to the full entropy, but more generally it is a statement about the additivity of universal terms in the entropy. Our proof simultaneously extends and simplifies previous arguments, with extensions including new models at zero temperature as well as the ability to treat finite temperature crossovers. We emphasize that while the additivity is an exact statement, each term in the sum may still be difficult to compute. Our results apply to a wide variety of phases including Fermi liquids, spin liquids, and some non-Fermi liquid metals. For example, we prove that our model of an interacting Fermi liquid has exactly the log violation of the area law for entanglement entropy predicted by the Widom formula in agreement with earlier arguments.

LETTER TO THE EDITOR: The quantum Knizhnik Zamolodchikov equation, generalized Razumov Stroganov sum rules and extended Joseph polynomials

NASA Astrophysics Data System (ADS)

Di Francesco, P.; Zinn-Justin, P.

2005-12-01

We prove higher rank analogues of the Razumov Stroganov sum rule for the ground state of the O(1) loop model on a semi-infinite cylinder: we show that a weighted sum of components of the ground state of the Ak-1 IRF model yields integers that generalize the numbers of alternating sign matrices. This is done by constructing minimal polynomial solutions of the level 1 U_q(\\widehat{\\frak{sl}(k)}) quantum Knizhnik Zamolodchikov equations, which may also be interpreted as quantum incompressible q-deformations of quantum Hall effect wavefunctions at filling fraction ν = k. In addition to the generalized Razumov Stroganov point q = -eiπ/k+1, another combinatorially interesting point is reached in the rational limit q → -1, where we identify the solution with extended Joseph polynomials associated with the geometry of upper triangular matrices with vanishing kth power.

QCD as a Theory of Hadrons

NASA Astrophysics Data System (ADS)

Narison, Stephan

2004-05-01

About Stephan Narison; Outline of the book; Preface; Acknowledgements; Part I. General Introduction: 1. A short flash on particle physics; 2. The pre-QCD era; 3. The QCD story; 4. Field theory ingredients; Part II. QCD Gauge Theory: 5. Lagrangian and gauge invariance; 6. Quantization using path integral; 7. QCD and its global invariance; Part III. MS scheme for QCD and QED: Introduction; 8. Dimensional regularization; 9. The MS renormalization scheme; 10. Renormalization of operators using the background field method; 11. The renormalization group; 12. Other renormalization schemes; 13. MS scheme for QED; 14. High-precision low-energy QED tests; Part IV. Deep Inelastic Scattering at Hadron Colliders: 15. OPE for deep inelastic scattering; 16. Unpolarized lepton-hadron scattering; 17. The Altarelli-Parisi equation; 18. More on unpolarized deep inelastic scatterings; 19. Polarized deep-inelastic processes; 20. Drell-Yan process; 21. One 'prompt photon' inclusive production; Part V. Hard Processes in e+e- Collisions: Introduction; 22. One hadron inclusive production; 23. gg scatterings and the 'spin' of the photon; 24. QCD jets; 25. Total inclusive hadron productions; Part VI. Summary of QCD Tests and as Measurements; Part VII. Power Corrections in QCD: 26. Introduction; 27. The SVZ expansion; 28. Technologies for evaluating Wilson coefficients; 29. Renormalons; 30. Beyond the SVZ expansion; Part VIII. QCD Two-Point Functions: 31. References guide to original works; 32. (Pseudo)scalar correlators; 33. (Axial-)vector two-point functions; 34. Tensor-quark correlator; 35. Baryonic correlators; 36. Four-quark correlators; 37. Gluonia correlators; 38. Hybrid correlators; 39. Correlators in x-space; Part IX. QCD Non-Perturbative Methods: 40. Introduction; 41. Lattice gauge theory; 42. Chiral perturbation theory; 43. Models of the QCD effective action; 44. Heavy quark effective theory; 45. Potential approaches to quarkonia; 46. On monopole and confinement; Part X. QCD Spectral Sum Rules: 47. Introduction; 48. Theoretical foundations; 49. Survey of QCD spectral sum rules; 50. Weinberg and DMO sum rules; 51. The QCD coupling as; 52. The QCD condensates; 53. Light and heavy quark masses, etc.; 54. Hadron spectroscopy; 55. D, B and Bc exclusive weak decays; 56. B0(s)-B0(s) mixing, kaon CP violation; 57. Thermal behaviour of QCD; 58. More on spectral sum rules; Part XI. Appendix A: physical constants and unites; Appendix B: weight factors for SU(N)c; Appendix C: coordinates and momenta; Appendix D: Dirac equation and matrices; Appendix E: Feynman rules; Appendix F: Feynman integrals; Appendix G: useful formulae for the sum rules; Bibliography; Index.

QCD as a Theory of Hadrons

NASA Astrophysics Data System (ADS)

Narison, Stephan

2007-07-01

About Stephan Narison; Outline of the book; Preface; Acknowledgements; Part I. General Introduction: 1. A short flash on particle physics; 2. The pre-QCD era; 3. The QCD story; 4. Field theory ingredients; Part II. QCD Gauge Theory: 5. Lagrangian and gauge invariance; 6. Quantization using path integral; 7. QCD and its global invariance; Part III. MS scheme for QCD and QED: Introduction; 8. Dimensional regularization; 9. The MS renormalization scheme; 10. Renormalization of operators using the background field method; 11. The renormalization group; 12. Other renormalization schemes; 13. MS scheme for QED; 14. High-precision low-energy QED tests; Part IV. Deep Inelastic Scattering at Hadron Colliders: 15. OPE for deep inelastic scattering; 16. Unpolarized lepton-hadron scattering; 17. The Altarelli-Parisi equation; 18. More on unpolarized deep inelastic scatterings; 19. Polarized deep-inelastic processes; 20. Drell-Yan process; 21. One 'prompt photon' inclusive production; Part V. Hard Processes in e+e- Collisions: Introduction; 22. One hadron inclusive production; 23. gg scatterings and the 'spin' of the photon; 24. QCD jets; 25. Total inclusive hadron productions; Part VI. Summary of QCD Tests and as Measurements; Part VII. Power Corrections in QCD: 26. Introduction; 27. The SVZ expansion; 28. Technologies for evaluating Wilson coefficients; 29. Renormalons; 30. Beyond the SVZ expansion; Part VIII. QCD Two-Point Functions: 31. References guide to original works; 32. (Pseudo)scalar correlators; 33. (Axial-)vector two-point functions; 34. Tensor-quark correlator; 35. Baryonic correlators; 36. Four-quark correlators; 37. Gluonia correlators; 38. Hybrid correlators; 39. Correlators in x-space; Part IX. QCD Non-Perturbative Methods: 40. Introduction; 41. Lattice gauge theory; 42. Chiral perturbation theory; 43. Models of the QCD effective action; 44. Heavy quark effective theory; 45. Potential approaches to quarkonia; 46. On monopole and confinement; Part X. QCD Spectral Sum Rules: 47. Introduction; 48. Theoretical foundations; 49. Survey of QCD spectral sum rules; 50. Weinberg and DMO sum rules; 51. The QCD coupling as; 52. The QCD condensates; 53. Light and heavy quark masses, etc.; 54. Hadron spectroscopy; 55. D, B and Bc exclusive weak decays; 56. B0(s)-B0(s) mixing, kaon CP violation; 57. Thermal behaviour of QCD; 58. More on spectral sum rules; Part XI. Appendix A: physical constants and unites; Appendix B: weight factors for SU(N)c; Appendix C: coordinates and momenta; Appendix D: Dirac equation and matrices; Appendix E: Feynman rules; Appendix F: Feynman integrals; Appendix G: useful formulae for the sum rules; Bibliography; Index.

Improving detection of dementia in Asian patients with low education: combining the Mini-Mental State Examination and the Informant Questionnaire on Cognitive Decline in the Elderly.

PubMed

Narasimhalu, Kaavya; Lee, June; Auchus, Alexander P; Chen, Christopher P L H

2008-01-01

Previous work combining the Mini-Mental State Examination (MMSE) and Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) has been conducted in western populations. We ascertained, in an Asian population, (1) the best method of combining the tests, (2) the effects of educational level, and (3) the effect of different dementia etiologies. Data from 576 patients were analyzed (407 nondemented controls, 87 Alzheimer's disease and 82 vascular dementia patients). Sensitivity, specificity and AUC values were obtained using three methods, the 'And' rule, the 'Or' rule, and the 'weighted sum' method. The 'weighted sum' rule had statistically superior AUC and specificity results, while the 'Or' rule had the best sensitivity results. The IQCODE outperformed the MMSE in all analyses. Patients with no education benefited more from combined tests. There was no difference between Alzheimer's disease and vascular dementia populations in the predictive value of any of the combined methods. We recommend that the IQCODE be used to supplement the MMSE whenever available and that the 'weighted sum' method be used to combine the MMSE and the IQCODE, particularly in populations with low education. As the study population selected may not be representative of the general population, further studies are required before generalization to nonclinical samples. (c) 2007 S. Karger AG, Basel.

Justifying the naive partonic sum rule for proton spin

DOE PAGES

Ji, Xiangdong; Zhang, Jian-Hui; Zhao, Yong

2015-04-01

We provide a theoretical basis for understanding the spin structure of the proton in terms of the spin and orbital angular momenta of free quarks and gluons in Feynman’s parton picture. We show that each term in the Jaffe–Manohar spin sum rule can be related to the matrix element of a gauge-invariant, but frame-dependent operator through a matching formula in large-momentum effective field theory. We present all the matching conditions for the spin content at one-loop order in perturbation theory, which provide a basis to calculate parton orbital angular momentum in lattice QCD at leading logarithmic accuracy.

Flavor changing neutral current transition of B to a1 with light-cone sum rules

NASA Astrophysics Data System (ADS)

Momeni, S.; Khosravi, R.; Falahati, F.

2017-01-01

The B →a1ℓ+ℓ- decays occur by the electroweak penguin and box diagrams, which can be performed through the flavor changing neutral current (FCNC). We calculate the form factors of the FCNC B →a1 transitions in the light-cone sum rules approach, up to twist-4 distribution amplitudes of the axial vector meson a1. Forward-backward asymmetry, as well as branching ratios of B →a1ℓ+ℓ-, and B →a1γ decays are considered. A comparison is also made between our results and the predictions of other methods.

Origin of the violation of the Gottfried sum rule

NASA Astrophysics Data System (ADS)

Hwang, W.-Y. P.; Speth, J.

1992-08-01

Using generalized Sullivan processes to generate sea-quark distributions of a nucleon at Q2=4 GeV2, we find that the recent finding by the New Muon Collaboration on the violation of the Gottfried sum rule can be understood quantitatively, including the shape of Fp2(x)-Fn2(x) as a function of x. The agreement may be seen as a clear evidence toward the validity of a recent suggestion of Hwang, Speth, and Brown that the sea distributions of a hadron, at low and moderate Q2 (at least up to a few GeV2), may be attributed primarily to generalized Sullivan processes.

Giant quadrupole and monopole resonances in /sup 28/Si

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

Lui, Y.; Bronson, J.D.; Youngblood, D.H.

1985-05-01

Inelastic alpha scattering measurements have been performed for /sup 28/Si at small angles including zero degrees. A total of 66% of the E0 energy-weighted sum rule was identified (using a Satchler version 2 form factor) centered at E/sub x/ = 17.9 MeV having a width of 4.8 MeV and 34% of the E2 energy-weighted sum rule was identified above E/sub x/ = 15.3 MeV centered at 19.0 MeV with a width of 4.4 MeV. The dependence of the extracted E0 strength on form factor and optical potential was explored.

Longitudinal leading-twist distribution amplitude of the J /ψ meson within the background field theory

NASA Astrophysics Data System (ADS)

Fu, Hai-Bing; Zeng, Long; Cheng, Wei; Wu, Xing-Gang; Zhong, Tao

2018-04-01

We make a detailed study on the J /ψ meson longitudinal leading-twist distribution amplitude ϕ2;J /ψ ∥ by using the QCD sum rules within the background field theory. By keeping all the nonperturbative condensates up to dimension 6, we obtain accurate QCD sum rules for the moments ⟨ξn;J /ψ ∥⟩. The first three ones are ⟨ξ2;J /ψ ∥⟩=0.083 (12 ), ⟨ξ4;J /ψ ∥⟩=0.015 (5 ), and ⟨ξ6;J /ψ ∥⟩=0.003 (2 ), respectively. Those values indicate a single peaked behavior for ϕ2;J /ψ ∥. As an application, we adopt the QCD light-cone sum rules to calculate the Bc meson semileptonic decay Bc+→J /ψ ℓ+νℓ. We obtain Γ (Bc+→J /ψ ℓ+νℓ)=(89.67-19.06+24.76)×10-15 GeV and ℜ(J /ψ ℓ+νℓ)=0.21 7-0.057+0.069, which agree with both the extrapolated next-to-leading order pQCD prediction and the new CDF measurement within errors.

Relativistic interpretation of the nature of the nuclear tensor force

NASA Astrophysics Data System (ADS)

Zong, Yao-Yao; Sun, Bao-Yuan

2018-02-01

The spin-dependent nature of the nuclear tensor force is studied in detail within the relativistic Hartree-Fock approach. The relativistic formalism for the tensor force is supplemented with an additional Lorentz-invariant tensor formalism in the σ-scalar channel, so as to take into account almost fully the nature of the tensor force brought about by the Fock diagrams in realistic nuclei. Specifically, the tensor sum rules are tested for the spin and pseudo-spin partners with and without nodes, to further understand the nature of the tensor force within the relativistic model. It is shown that the interference between the two components of nucleon spinors causes distinct violations of the tensor sum rules in realistic nuclei, mainly due to the opposite signs on the κ quantities of the upper and lower components, as well as the nodal difference. However, the sum rules can be precisely reproduced if the same radial wave functions are taken for the spin/pseudo-spin partners in addition to neglecting the lower/upper components, revealing clearly the nature of the tensor force. Supported by National Natural Science Foundation of China (11375076, 11675065) and the Fundamental Research Funds for the Central Universities (lzujbky-2016-30)

Spectral sum rules and magneto-roton as emergent graviton in fractional quantum Hall effect

DOE PAGES

Golkar, Siavash; Nguyen, Dung X.; Son, Dam T.

2016-01-05

Here, we consider gapped fractional quantum Hall states on the lowest Landau level when the Coulomb energy is much smaller than the cyclotron energy. We introduce two spectral densities, ρ T(ω) andmore » $$\\bar{p}$$ T(ω), which are proportional to the probabilities of absorption of circularly polarized gravitons by the quantum Hall system. We prove three sum rules relating these spectral densities with the shift S, the q 4 coefficient of the static structure factor S 4, and the high-frequency shear modulus of the ground state μ ∞, which is precisely defined. We confirm an inequality, first suggested by Haldane, that S 4 is bounded from below by |S–1|/8. The Laughlin wavefunction saturates this bound, which we argue to imply that systems with ground state wavefunctions close to Laughlin’s absorb gravitons of predominantly one circular polarization. We consider a nonlinear model where the sum rules are saturated by a single magneto-roton mode. In this model, the magneto-roton arises from the mixing between oscillations of an internal metric and the hydrodynamic motion. Implications for experiments are briefly discussed.« less

Semiclassical approaches to nuclear dynamics

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

Magner, A. G., E-mail: magner@kinr.kiev.ua; Gorpinchenko, D. V.; Bartel, J.

The extended Gutzwiller trajectory approach is presented for the semiclassical description of nuclear collective dynamics, in line with the main topics of the fruitful activity of V.G. Solovjov. Within the Fermi-liquid droplet model, the leptodermous effective surface approximation was applied to calculations of energies, sum rules, and transition densities for the neutron–proton asymmetry of the isovector giant-dipole resonance and found to be in good agreement with the experimental data. By using the Strutinsky shell correction method, the semiclassical collective transport coefficients, such as nuclear inertia, friction, stiffness, and moments of inertia, can be derived beyond the quantum perturbation approximation ofmore » the response function theory and the cranking model. The averaged particle-number dependences of the low-lying collective vibrational states are described in good agreement with the basic experimental data, mainly due to the enhancement of the collective inertia as compared to its irrotational flow value. Shell components of the moment of inertia are derived in terms of the periodic-orbit free-energy shell corrections. A good agreement between the semiclassical extended Thomas–Fermi moments of inertia with shell corrections and the quantum results is obtained for different nuclear deformations and particle numbers. Shell effects are shown to be exponentially dampted out with increasing temperature in all the transport coefficients.« less

Study of Water Absorption Lines in the Near Infrared

DTIC Science & Technology

1975-02-17

the absorption coefficient is better approximated by the sum of Matcha -N«. oec short range contribution and W-BB dispersion contribution. The...and W. Byers Brown, Molecular Physics 2S, 1105 (1973). 5. R. L. Matcha and R. K. Nesbet, Phys. Rev. 1_6_0, 72 (1967). I H. B. Levine, Phys. Rev...reasurcrents of Ouren, ^eltqen Gaide, Helbing and Pauly. The dipole moment function is taken from ab initio 9 calculations of Matcha and Nesbet. With

Combining High Sensitivity Cardiac Troponin I and Cardiac Troponin T in the Early Diagnosis of Acute Myocardial Infarction.

PubMed

van der Linden, Noreen; Wildi, Karin; Twerenbold, Raphael; Pickering, John W; Than, Martin; Cullen, Louise; Greenslade, Jaimi; Parsonage, William; Nestelberger, Thomas; Boeddinghaus, Jasper; Badertscher, Patrick; Rubini Giménez, Maria; Klinkenberg, Lieke J J; Bekers, Otto; Schöni, Aline; Keller, Dagmar I; Sabti, Zaid; Puelacher, Christian; Cupa, Janosch; Schumacher, Lukas; Kozhuharov, Nikola; Grimm, Karin; Shrestha, Samyut; Flores, Dayana; Freese, Michael; Stelzig, Claudia; Strebel, Ivo; Miró, Òscar; Rentsch, Katharina; Morawiec, Beata; Kawecki, Damian; Kloos, Wanda; Lohrmann, Jens; Richards, A Mark; Troughton, Richard; Pemberton, Christopher; Osswald, Stefan; van Dieijen-Visser, Marja P; Mingels, Alma M; Reichlin, Tobias; Meex, Steven J R; Mueller, Christian

2018-04-24

Background -Combining two signals of cardiomyocyte injury, cardiac troponin I (cTnI) and T (cTnT), might overcome some individual pathophysiological and analytical limitations and thereby increase diagnostic accuracy for acute myocardial infarction (AMI) with a single blood draw. We aimed to evaluate the diagnostic performance of combinations of high sensitivity (hs) cTnI and hs-cTnT for the early diagnosis of AMI. Methods -The diagnostic performance of combining hs-cTnI (Architect, Abbott) and hs-cTnT (Elecsys, Roche) concentrations (sum, product, ratio and a combination algorithm) obtained at the time of presentation was evaluated in a large multicenter diagnostic study of patients with suspected AMI. The optimal rule out and rule in thresholds were externally validated in a second large multicenter diagnostic study. The proportion of patients eligible for early rule out was compared with the ESC 0/1 and 0/3 hour algorithms. Results -Combining hs-cTnI and hs-cTnT concentrations did not consistently increase overall diagnostic accuracy as compared with the individual isoforms. However, the combination improved the proportion of patients meeting criteria for very early rule-out. With the ESC 2015 guideline recommended algorithms and cut-offs, the proportion meeting rule out criteria after the baseline blood sampling was limited (6-24%) and assay dependent. Application of optimized cut-off values using the sum (9 ng/L) and product (18 ng2/L2) of hs-cTnI and hs-cTnT concentrations led to an increase in the proportion ruled-out after a single blood draw to 34-41% in the original (sum: negative predictive value (NPV) 100% (95%CI: 99.5-100%); product: NPV 100% (95%CI: 99.5-100%) and in the validation cohort (sum: NPV 99.6% (95%CI: 99.0-99.9%); product: NPV 99.4% (95%CI: 98.8-99.8%). The use of a combination algorithm (hs-cTnI <4 ng/L and hs-cTnT <9 ng/L) showed comparable results for rule out (40-43% ruled out; NPV original cohort 99.9% (95%CI: 99.2-100%); NPV validation cohort 99.5% (95%CI: 98.9-99.8%)) and rule-in (PPV original cohort 74.4% (95%Cl 69.6-78.8%); PPV validation cohort 84.0% (95%Cl 79.7-87.6%)). Conclusions -New strategies combining hs-cTnI and hs-cTnT concentrations may significantly increase the number of patients eligible for very early and safe rule-out, but do not seem helpful for the rule-in of AMI. Clinical Trial Registration -APACE URL: www.clinicaltrial.gov, Unique Identifier: NCT00470587; ADAPT URL: www.anzctr.org.au, Unique Identifier: ACTRN12611001069943.

76 FR 60565 - Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-29

... the same lien of securities of margin customers (a) with other customers without their written consent and (b) with the broker or dealer. The rule also prohibits the rehypothecation of customers' margin securities for a sum in excess of the customer's aggregate indebtedness. Pursuant to Rule 15c2-1, respondents...

Large-scale deformed quasiparticle random-phase approximation calculations of the γ -ray strength function using the Gogny force

NASA Astrophysics Data System (ADS)

Martini, M.; Péru, S.; Hilaire, S.; Goriely, S.; Lechaftois, F.

2016-07-01

Valuable theoretical predictions of nuclear dipole excitations in the whole chart are of great interest for different nuclear applications, including in particular nuclear astrophysics. Here we present large-scale calculations of the E 1 γ -ray strength function obtained in the framework of the axially symmetric deformed quasiparticle random-phase approximation based on the finite-range Gogny force. This approach is applied to even-even nuclei, the strength function for odd nuclei being derived by interpolation. The convergence with respect to the adopted number of harmonic oscillator shells and the cutoff energy introduced in the 2-quasiparticle (2 -q p ) excitation space is analyzed. The calculations performed with two different Gogny interactions, namely D1S and D1M, are compared. A systematic energy shift of the E 1 strength is found for D1M relative to D1S, leading to a lower energy centroid and a smaller energy-weighted sum rule for D1M. When comparing with experimental photoabsorption data, the Gogny-QRPA predictions are found to overestimate the giant dipole energy by typically ˜2 MeV. Despite the microscopic nature of our self-consistent Hartree-Fock-Bogoliubov plus QRPA calculation, some phenomenological corrections need to be included to take into account the effects beyond the standard 2 -q p QRPA excitations and the coupling between the single-particle and low-lying collective phonon degrees of freedom. For this purpose, three prescriptions of folding procedure are considered and adjusted to reproduce experimental photoabsorption data at best. All of them are shown to lead to somewhat similar predictions of the E 1 strength, both at low energies and for exotic neutron-rich nuclei. Predictions of γ -ray strength functions and Maxwellian-averaged neutron capture rates for the whole Sn isotopic chain are also discussed and compared with previous theoretical calculations.

Quantum phases for point-like charged particles and for electrically neutral dipoles in an electromagnetic field

NASA Astrophysics Data System (ADS)

Kholmetskii, A. L.; Missevitch, O. V.; Yarman, T.

2018-05-01

We point out that the known quantum phases for an electric/magnetic dipole moving in an electromagnetic (EM) field must be presented as the superposition of more fundamental quantum phases emerging for elementary charges. Using this idea, we find two new fundamental quantum phases for point-like charges, next to the known electric and magnetic Aharonov-Bohm (A-B) phases, named by us as the complementary electric and magnetic phases, correspondingly. We further demonstrate that these new phases can indeed be derived via the Schrödinger equation for a particle in an EM field, where however the operator of momentum is re-defined via the replacement of the canonical momentum of particle by the sum of its mechanical momentum and interactional field momentum for a system "charged particle and a macroscopic source of EM field". The implications of the obtained results are discussed.

Determining partial differential cross sections for low-energy electron photodetachment involving conical intersections using the solution of a Lippmann-Schwinger equation constructed with standard electronic structure techniques.

PubMed

Han, Seungsuk; Yarkony, David R

2011-05-07

A method for obtaining partial differential cross sections for low energy electron photodetachment in which the electronic states of the residual molecule are strongly coupled by conical intersections is reported. The method is based on the iterative solution to a Lippmann-Schwinger equation, using a zeroth order Hamiltonian consisting of the bound nonadiabatically coupled residual molecule and a free electron. The solution to the Lippmann-Schwinger equation involves only standard electronic structure techniques and a standard three-dimensional free particle Green's function quadrature for which fast techniques exist. The transition dipole moment for electron photodetachment, is a sum of matrix elements each involving one nonorthogonal orbital obtained from the solution to the Lippmann-Schwinger equation. An expression for the electron photodetachment transition dipole matrix element in terms of Dyson orbitals, which does not make the usual orthogonality assumptions, is derived.

Evaluation of atomic constants for optical radiation, volume 2

NASA Technical Reports Server (NTRS)

Kylstra, C. D.; Schneider, R. J.

1974-01-01

Various atomic constant for 23 elements from helium to mercury were computed and are presented in tables. The data given for each element start with the element name, its atomic number, its ionic state, and the designation and series limit for each parent configuration. This is followed by information on the energy level, parent configuration, and designation for each term available to the program. The matrix elements subtables are ordered by the sequence numbers, which represent the initial and final levels of the transitions. Each subtable gives the following: configuration of the core or parent, designation and energy level for the reference state, effective principal quantum number, energy of the series limit, value of the matrix element for the reference state interacting with itself, and sum of all of the dipole matrix elements listed in the subtable. Dipole and quadrupole interaction data are also given.

Low-Dimensional Nanostructures and a Semiclassical Approach for Teaching Feynman's Sum-over-Paths Quantum Theory

ERIC Educational Resources Information Center

Onorato, P.

2011-01-01

An introduction to quantum mechanics based on the sum-over-paths (SOP) method originated by Richard P. Feynman and developed by E. F. Taylor and coworkers is presented. The Einstein-Brillouin-Keller (EBK) semiclassical quantization rules are obtained following the SOP approach for bounded systems, and a general approach to the calculation of…

Drude Conductivity of Dirac Fermions in Graphene

DTIC Science & Technology

2010-01-01

interband transitions, as required by the sum rule. Our surprising observation indicates that many-body effects and Dirac fermion-impurity interactions...reduction of free electron oscillator strength is corroborated by corresponding changes in graphene interband transitions, as required by the sum...dimensions. Researchers have demonstrated in graphene exotic Dirac fermion phenomena ranging from anomalous quantum Hall effects 1,2 to Klein tunneling 3 in

Some effects of electron channeling on electron energy loss spectroscopy.

PubMed

Kirkland, Earl J

2005-02-01

As an electron beam (of order 100 keV) travels through a crystalline solid it can be channeled down a zone axis of the crystal to form a channeling peak centered on the atomic columns. The channeling peak can be similar in size to the outer atomic orbitals. Electron energy loss spectroscopy (EELS) measures the losses that the electron experiences as it passes through the solid yielding information about the unoccupied density of states in the solid. The interaction matrix element for this process typically produces dipole selection rules for small angle scattering. In this paper, a theoretical calculation of the EELS cross section in the presence of strong channeling is performed for the silicon L23 edge. The presence of channeling is found to alter both the intensity and selection rules for this EELS signal as a function of depth in the solid. At some depths in the specimen small but significant non-dipole transition components can be produced, which may influence measurements of the density of states in solids.

Scalar Hidden-Charm Tetraquark States with QCD Sum Rules

NASA Astrophysics Data System (ADS)

Di, Zun-Yan; Wang, Zhi-Gang; Zhang, Jun-Xia; Yu, Guo-Liang

2018-02-01

In this article, we study the masses and pole residues of the pseudoscalar-diquark-pseudoscalar-antidiquark type and vector-diquark-vector-antidiquark type scalar hidden-charm cu\\bar{c}\\bar{d} (cu\\bar{c}\\bar{s}) tetraquark states with QCD sum rules by taking into account the contributions of the vacuum condensates up to dimension-10 in the operator product expansion. The predicted masses can be confronted with the experimental data in the future. Possible decays of those tetraquark states are also discussed. Supported by the National Natural Science Foundation of China under Grant No. 11375063, the Fundamental Research Funds for the Central Universities under Grant Nos. 2016MS155 and 2016MS133

D mesons in a magnetic field

DOE PAGES

Gubler, Philipp; Hattori, Koichi; Lee, Su Houng; ...

2016-03-15

In this paper, we investigate the mass spectra of open heavy flavor mesons in an external constant magnetic field within QCD sum rules. Spectral Ansatze on the phenomenological side are proposed in order to properly take into account mixing effects between the pseudoscalar and vector channels, and the Landau levels of charged mesons. The operator product expansion is implemented up to dimension-5 operators. As a result, we find for neutral D mesons a significant positive mass shift that goes beyond simple mixing effects. In contrast, charged D mesons are further subject to Landau level effects, which together with the mixingmore » effects almost completely saturate the mass shifts obtained in our sum rule analysis.« less

Product-sum universality and Rushbrooke inequality in explosive percolation

NASA Astrophysics Data System (ADS)

Sabbir, M. M. H.; Hassan, M. K.

2018-05-01

We study explosive percolation (EP) on an Erdös-Rényi network for product rule (PR) and sum rule (SR). Initially, it was claimed that EP describes discontinuous phase transition; now it is well accepted as a probabilistic model for thermal continuous phase transition (CPT). However, no model for CPT is complete unless we know how to relate its observable quantities with those of thermal CPT. To this end, we define entropy and specific heat, redefine susceptibility, and show that they behave exactly like their thermal counterparts. We obtain the critical exponents ν ,α ,β , and γ numerically and find that both PR and SR belong to the same universality class and obey Rushbrooke inequality.

A fuzzy controller with nonlinear control rules is the sum of a global nonlinear controller and a local nonlinear PI-like controller

NASA Technical Reports Server (NTRS)

Ying, Hao

1993-01-01

The fuzzy controllers studied in this paper are the ones that employ N trapezoidal-shaped members for input fuzzy sets, Zadeh fuzzy logic and a centroid defuzzification algorithm for output fuzzy set. The author analytically proves that the structure of the fuzzy controllers is the sum of a global nonlinear controller and a local nonlinear proportional-integral-like controller. If N approaches infinity, the global controller becomes a nonlinear controller while the local controller disappears. If linear control rules are used, the global controller becomes a global two-dimensional multilevel relay which approaches a global linear proportional-integral (PI) controller as N approaches infinity.

The structure, mixing angle, mass and couplings of the light scalar f0(500) and f0(980) mesons

NASA Astrophysics Data System (ADS)

Agaev, S. S.; Azizi, K.; Sundu, H.

2018-06-01

The mixing angle, mass and couplings of the light scalar mesons f0 (500) and f0 (980) are calculated in the framework of QCD two-point sum rule approach by assuming that they are tetraquarks with diquark-antidiquark structures. The mesons are treated as mixtures of the heavy | H > = ([ su ] [ s bar u bar ] + [ sd ] [ s bar d bar ]) /√{ 2 } and light | L > = [ ud ] [ u bar d bar ] scalar diquark-antidiquark components. We extract from corresponding sum rules the mixing angles φH and φL of these states and evaluate the masses and couplings of the particles f0 (500) and f0 (980).

Channel branching ratios in CH2CN- photodetachment: Rotational structure and vibrational energy redistribution in autodetachment

NASA Astrophysics Data System (ADS)

Lyle, Justin; Wedig, Olivia; Gulania, Sahil; Krylov, Anna I.; Mabbs, Richard

2017-12-01

We report photoelectron spectra of CH2CN-, recorded at photon energies between 13 460 and 15 384 cm-1, which show rapid intensity variations in particular detachment channels. The branching ratios for various spectral features reveal rotational structure associated with autodetachment from an intermediate anion state. Calculations using equation-of-motion coupled-cluster method with single and double excitations reveal the presence of two dipole-bound excited anion states (a singlet and a triplet). The computed oscillator strength for the transition to the singlet dipole-bound state provides an estimate of the autodetachment channel contribution to the total photoelectron yield. Analysis of the different spectral features allows identification of the dipole-bound and neutral vibrational levels involved in the autodetachment processes. For the most part, the autodetachment channels are consistent with the vibrational propensity rule and normal mode expectation. However, examination of the rotational structure shows that autodetachment from the ν3 (v = 1 and v = 2) levels of the dipole-bound state displays behavior counter to the normal mode expectation with the final state vibrational level belonging to a different mode.

Correlation between structural change and electrical transport properties of Fe-doped chrysotile nanotubes under high pressure

NASA Astrophysics Data System (ADS)

Zhang, Junkai; Yang, Lili; Wu, Xiaoxin; Wei, Maobin; Liu, Yanqing; Gao, Chunxiao; Yang, Jinghai; Ma, Yanzhang

2018-04-01

Fe3+ doped chrysotile nanotubes (NTs) have been synthesized under controlled hydrothermal conditions, and have been characteristic of layered-walls and room-temperature ferromagnetism. High-pressure in situ impedance spectra and synchrotron XRD measurements are performed on Fe-doped chrysotile NTs to reveal the electrical transport and structural properties under compression. Sample resistance (R sum) was found to increase with the pressure elevation, accompanying the step decrease in the grain boundary relaxation frequency (f gb), which reflects the bandgap broadening and dipoles polarization weakening due to the application of pressure. Furthermore, it is found that both R sum and f gb change their pressure dependences at ~5.0 GPa, which is attributed to the nonlinear compressibility of c-axis and even the underlying lattice distortion of monoclinic structure obtained in the XRD observations.

Magnetoencephalography evidence for different brain subregions serving two musical cultures.

PubMed

Matsunaga, Rie; Yokosawa, Koichi; Abe, Jun-ichi

2012-12-01

Individuals who have been exposed to two different musical cultures (bimusicals) can be differentiated from those exposed to only one musical culture (monomusicals). Just as bilingual speakers handle the distinct language-syntactic rules of each of two languages, bimusical listeners handle two distinct musical-syntactic rules (e.g., tonal schemas) in each musical culture. This study sought to determine specific brain activities that contribute to differentiating two culture-specific tonal structures. We recorded magnetoencephalogram (MEG) responses of bimusical Japanese nonmusicians and amateur musicians as they monitored unfamiliar Western melodies and unfamiliar, but traditional, Japanese melodies, both of which contained tonal deviants (out-of-key tones). Previous studies with Western monomusicals have shown that tonal deviants elicit an early right anterior negativity (mERAN) originating in the inferior frontal cortex. In the present study, tonal deviants in both Western and Japanese melodies elicited mERANs with characteristics fitted by dipoles around the inferior frontal gyrus in the right hemisphere and the premotor cortex in the left hemisphere. Comparisons of the nature of mERAN activity to Western and Japanese melodies showed differences in the dipoles' locations but not in their peak latency or dipole strength. These results suggest that the differentiation between a tonal structure of one culture and that of another culture correlates with localization differences in brain subregions around the inferior frontal cortex and the premotor cortex. Copyright © 2012 Elsevier Ltd. All rights reserved.

Brightened spin-triplet interlayer excitons and optical selection rules in van der Waals heterobilayers

NASA Astrophysics Data System (ADS)

Yu, Hongyi; Liu, Gui-Bin; Yao, Wang

2018-07-01

We investigate the optical properties of spin-triplet interlayer excitons in heterobilayer transition metal dichalcogenides in comparison with the spin-singlet ones. Surprisingly, the optical transition dipole of the spin-triplet exciton is found to be in the same order of magnitude to that of the spin-singlet exciton, in sharp contrast to the monolayer excitons where the spin-triplet species is considered as dark compared to the singlet. Unlike the monolayer excitons whose spin-conserved (spin-flip) transition dipole can only couple to light of in-plane (out-of-plane) polarisation, such restriction is removed for the interlayer excitons due to the breaking of the out-of-plane mirror symmetry. We find that as the interlayer atomic registry changes, the optical transition dipole of interlayer exciton crosses between in-plane ones of opposite circular polarizations and the out-of-plane one for both the spin-triplet and spin-singlet species. As a result, excitons of both species have non-negligible coupling into photon modes of both in-plane and out-of-plane propagations, another sharp difference from the monolayers where the exciton couples predominantly into the out-of-plane propagation channel. At given atomic registry, the spin-triplet and spin-singlet excitons have distinct valley polarisation selection rules, allowing the selective optical addressing of both the valley configuration and the spin-singlet/triplet configuration of interlayer excitons.

Adler function and Bjorken polarized sum rule: Perturbation expansions in powers of the S U (Nc) conformal anomaly and studies of the conformal symmetry limit

NASA Astrophysics Data System (ADS)

Cvetič, Gorazd; Kataev, A. L.

2016-07-01

We consider a new form of analytical perturbation theory expansion in the massless S U (Nc) theory, for the nonsinglet part of the e+e--annihilation to hadrons Adler function Dn s and of the Bjorken sum rule of the polarized lepton-hadron deep-inelastic scattering Cns B j p, and demonstrate its validity at the O (αs4)-level at least. It is a two-fold series in powers of the conformal anomaly and of S U (Nc) coupling αs. Explicit expressions are obtained for the {β }-expanded perturbation coefficients at O (αs4) level in MS ¯ scheme, for both considered physical quantities. Comparisons of the terms in the {β }-expanded coefficients are made with the corresponding terms obtained by using extra gluino degrees of freedom, or skeleton-motivated expansion, or Rδ-scheme motivated expansion in the Principle of Maximal Conformality. Relations between terms of the {β }-expansion for the Dn s- and Cns B j p-functions, which follow from the conformal symmetry limit and its violation, are presented. The relevance to the possible new analyses of the experimental data for the Adler function and Bjorken sum rule is discussed.

26 CFR 1.848-2 - Determination of net premiums.

Code of Federal Regulations, 2010 CFR

2010-04-01

... contracts. With respect to any category of contracts, net premiums means— (i) The gross amount of premiums... subject to the rules of paragraph (h) of this section. (b) Gross amount of premiums and other consideration—(1) General rule. The term “gross amount of premiums and other consideration” means the sum of— (i...

Europa's induced magnetic field: How much of the signal is from the ocean?

NASA Astrophysics Data System (ADS)

Crary, F. J.; Dols, V. J.; Jia, X.; Paty, C. S.; Hale, J. M.

2017-12-01

The existence of a sub-surface ocean within Europa was demonstrated by the Galileo spacecraft's measurements of an induced dipole magnetic field. This field, produced by the time variable background magnetic field from Jupiter, is a result of currents flowing within an electrically conductive layer inside Europa, believed to be a liquid ocean. Unfortunately, interpretation of the Galileo results is complicated by the interaction between Jupiter's magnetosphere and Europa and its ionosphere. This interaction also produces magnetic field perturbations which add uncertainty and systematic errors to the determination of the induced field.Here, we estimate the contribution of the plasma interaction to the observed magnetic dipole, and discuss the implications for the properties of Europa's subsurface ocean. The Galileo data have primarily been analyzed by fitting a dipole to the observed magnetic field, without correcting for plasma effects. The data were fit to a dipole magnetic field, and the resulting magnetic moment is the sum of the induced moment from the ocean and a contribution from the plasma interaction. To estimate this contribution, we analyze the results of numerical simulations using exactly the same approach which has been used to analyze the real data. Since we know what ocean dipole was inserted in the models' boundary conditions, we therefore calculate the contribution from the plasma interaction. We have previously used this approach to estimate the sensitivity of the results to upstream plasma conditions. However, there is no assurance that one particular model is correct. In this work, we apply this approach to several different types of simulations, shedding light on the uncertainties in the ocean-induced signature.

Studies of singlet Rydberg series of LiH derived from Li(nl) + H(1s), with n ≤ 6 and l ≤ 4

NASA Astrophysics Data System (ADS)

Gim, Yeongrok; Lee, Chun-Woo

2014-10-01

The 50 singlet states of LiH composed of 49 Rydberg states and one non-Rydberg ionic state derivable from Li(nl) + H(1s), with n ≤ 6 and l ≤ 4, are studied using the multi-reference configuration interaction method combined with the Stuttgart/Köln group's effective core potential/core polarization potential method. Basis functions that can yield energy levels up to the 6g orbital of Li have been developed, and they are used with a huge number of universal Kaufmann basis functions for Rydberg states. The systematics and regularities of the physical properties such as potential energies, quantum defects, permanent dipole moments, transition dipole moments, and nonadiabatic coupling matrix elements of the Rydberg series are studied. The behaviors of potential energy curves and quantum defect curves are explained using the Fermi approximation. The permanent dipole moments of the Rydberg series reveal that they are determined by the sizes of the Rydberg orbitals, which are proportional to n2. Interesting mirror relationships of the dipole moments are observed between l-mixed Rydberg series, with the rule Δl = ±1, except for s-d mixing, which is also accompanied by n-mixing. The members of the l-mixed Rydberg series have dipole moments with opposite directions. The first derivatives of the dipole moment curves, which show the charge-transfer component, clearly show not only mirror relationships in terms of direction but also oscillations. The transition dipole moment matrix elements of the Rydberg series are determined by the small-r region, with two consequences. One is that the transition dipole moment matrix elements show n-3/2 dependence. The other is that the magnitudes of the transition dipole moment matrix elements decrease rapidly as l increases.

Selection rule engineering of forbidden transitions of a hydrogen atom near a nanogap

NASA Astrophysics Data System (ADS)

Kim, Hyunyoung Y.; Kim, Daisik S.

2018-01-01

We perform an analytical study on the allowance of forbidden transitions for a hydrogen atom placed near line dipole sources, mimicking light emanating from a one-dimensional metallic nanogap. It is shown that the rapid variation of the electric field vector, inevitable in the near zone, completely breaks the selection rule of Δl=±1. While the forbidden transitions between spherically symmetric S states, such as 2S to 1S or 3S to 1S (Δl=0), are rather robust against selection rule breakage, Δl=±2 transitions such as between 3D and 1S or 3D and 2S states are very vulnerable to the spatial variation of the perturbing electric field. Transitions between 2S and 3D states are enhanced by many orders of magnitude, aided by the quadratic nature of both the perturbing Hamiltonian and D wavefunctions. The forbidden dipole moment, which approaches one Bohr radius times the electric charge in the vicinity of the gap, can be written in a simple closed form owing to the one-dimensional nature of our gap. With large enough effective volume together with the symmetric nature of the excited state wavefunctions, our work paves way towards atomic physics application of infinitely long nanogaps.

Chimera distribution amplitudes for the pion and the longitudinally polarized ρ-meson

NASA Astrophysics Data System (ADS)

Stefanis, N. G.; Pimikov, A. V.

2016-01-01

Using QCD sum rules with nonlocal condensates, we show that the distribution amplitude of the longitudinally polarized ρ-meson may have a shorttailed platykurtic profile in close analogy to our recently proposed platykurtic distribution amplitude for the pion. Such a chimera distribution de facto amalgamates the broad unimodal profile of the distribution amplitude, obtained with a Dyson-Schwinger equations-based computational scheme, with the suppressed tails characterizing the bimodal distribution amplitudes derived from QCD sum rules with nonlocal condensates. We argue that pattern formation, emerging from the collective synchronization of coupled oscillators, can provide a single theoretical scaffolding to study unimodal and bimodal distribution amplitudes of light mesons without recourse to particular computational schemes and the reasons for them.

Asymptotic 3-loop heavy flavor corrections to the charged current structure functions FLW+-W-(x ,Q2) and F2W+-W-(x ,Q2)

NASA Astrophysics Data System (ADS)

Behring, A.; Blümlein, J.; Falcioni, G.; De Freitas, A.; von Manteuffel, A.; Schneider, C.

2016-12-01

We derive the massive Wilson coefficients for the heavy flavor contributions to the nonsinglet charged current deep-inelastic scattering structure functions FLW+(x ,Q2)-FLW-(x ,Q2) and F2W+(x ,Q2)-F2W-(x ,Q2) in the asymptotic region Q2≫m2 to 3-loop order in quantum chromodynamics at general values of the Mellin variable N and the momentum fraction x . Besides the heavy quark pair production, also the single heavy flavor excitation s →c contributes. Numerical results are presented for the charm quark contributions, and consequences on the unpolarized Bjorken sum rule and Adler sum rule are discussed.

Mining HIV protease cleavage data using genetic programming with a sum-product function.

PubMed

Yang, Zheng Rong; Dalby, Andrew R; Qiu, Jing

2004-12-12

In order to design effective HIV inhibitors, studying and understanding the mechanism of HIV protease cleavage specification is critical. Various methods have been developed to explore the specificity of HIV protease cleavage activity. However, success in both extracting discriminant rules and maintaining high prediction accuracy is still challenging. The earlier study had employed genetic programming with a min-max scoring function to extract discriminant rules with success. However, the decision will finally be degenerated to one residue making further improvement of the prediction accuracy difficult. The challenge of revising the min-max scoring function so as to improve the prediction accuracy motivated this study. This paper has designed a new scoring function called a sum-product function for extracting HIV protease cleavage discriminant rules using genetic programming methods. The experiments show that the new scoring function is superior to the min-max scoring function. The software package can be obtained by request to Dr Zheng Rong Yang.

A resolution of the inclusive flavor-breaking τ |Vus| puzzle

NASA Astrophysics Data System (ADS)

Hudspith, Renwick J.; Lewis, Randy; Maltman, Kim; Zanotti, James

2018-06-01

We revisit the puzzle of |Vus | values obtained from the conventional implementation of hadronic-τ- decay-based flavor-breaking finite-energy sum rules lying > 3 σ below the expectations of three-family unitarity. Significant unphysical dependences of |Vus | on the choice of weight, w, and upper limit, s0, of the experimental spectral integrals entering the analysis are confirmed, and a breakdown of assumptions made in estimating higher dimension, D > 4, OPE contributions identified as the main source of these problems. A combination of continuum and lattice results is shown to suggest a new implementation of the flavor-breaking sum rule approach in which not only |Vus |, but also D > 4 effective condensates, are fit to data. Lattice results are also used to clarify how to reliably treat the slowly converging D = 2 OPE series. The new sum rule implementation is shown to cure the problems of the unphysical w- and s0-dependence of |Vus | and to produce results ∼0.0020 higher than those of the conventional implementation employing the same data. With B-factory input, and using, in addition, dispersively constrained results for the Kπ branching fractions, we find |Vus | = 0.2231(27)exp(4)th, in excellent agreement with the result from Kℓ3, and compatible within errors with the expectations of three-family unitarity, thus resolving the long-standing inclusive τ |Vus | puzzle.

Modeling and analysis of CSAMT field source effect and its characteristics

NASA Astrophysics Data System (ADS)

Da, Lei; Xiaoping, Wu; Qingyun, Di; Gang, Wang; Xiangrong, Lv; Ruo, Wang; Jun, Yang; Mingxin, Yue

2016-02-01

Controlled-source audio-frequency magnetotellurics (CSAMT) has been a highly successful geophysical tool used in a variety of geological exploration studies for many years. However, due to the artificial source used in the CSAMT technique, two important factors are considered during interpretation: non-plane-wave or geometric effects and source overprint effects. Hence, in this paper we simulate the source overprint effects and analyzed the rule and characteristics of its influence on CSAMT applications. Two-dimensional modeling was carried out using an adaptive unstructured finite element method to simulate several typical models. Also, we summarized the characteristics and rule of the source overprint effects and analyzed its influence on the data taken over several mining areas. The results obtained from the study shows that the occurrence and strength of the source overprint effect is dependent on the location of the source dipole, in relation to the receiver and the subsurface geology. In order to avoid source overprint effects, three principle were suggested to determine the best location for the grounded dipole source in the field.

Studies of singlet Rydberg series of LiH derived from Li(nl) + H(1s), with n ≤ 6 and l ≤ 4

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

Gim, Yeongrok; Department of Chemistry, Ajou University, Suwon 443-749; Lee, Chun-Woo, E-mail: clee@ajou.ac.kr

2014-10-14

The 50 singlet states of LiH composed of 49 Rydberg states and one non-Rydberg ionic state derivable from Li(nl) + H(1s), with n ≤ 6 and l ≤ 4, are studied using the multi-reference configuration interaction method combined with the Stuttgart/Köln group's effective core potential/core polarization potential method. Basis functions that can yield energy levels up to the 6g orbital of Li have been developed, and they are used with a huge number of universal Kaufmann basis functions for Rydberg states. The systematics and regularities of the physical properties such as potential energies, quantum defects, permanent dipole moments, transition dipolemore » moments, and nonadiabatic coupling matrix elements of the Rydberg series are studied. The behaviors of potential energy curves and quantum defect curves are explained using the Fermi approximation. The permanent dipole moments of the Rydberg series reveal that they are determined by the sizes of the Rydberg orbitals, which are proportional to n{sup 2}. Interesting mirror relationships of the dipole moments are observed between l-mixed Rydberg series, with the rule Δl = ±1, except for s–d mixing, which is also accompanied by n-mixing. The members of the l-mixed Rydberg series have dipole moments with opposite directions. The first derivatives of the dipole moment curves, which show the charge-transfer component, clearly show not only mirror relationships in terms of direction but also oscillations. The transition dipole moment matrix elements of the Rydberg series are determined by the small-r region, with two consequences. One is that the transition dipole moment matrix elements show n{sup −3/2} dependence. The other is that the magnitudes of the transition dipole moment matrix elements decrease rapidly as l increases.« less

Sum-rule corrections: a route to error cancellations in correlation matrix renormalisation theory

NASA Astrophysics Data System (ADS)

Liu, C.; Liu, J.; Yao, Y. X.; Wang, C. Z.; Ho, K. M.

2017-03-01

We recently proposed the correlation matrix renormalisation (CMR) theory to efficiently and accurately calculate ground state total energy of molecular systems, based on the Gutzwiller variational wavefunction (GWF) to treat the electronic correlation effects. To help reduce numerical complications and better adapt the CMR to infinite lattice systems, we need to further refine the way to minimise the error originated from the approximations in the theory. This conference proceeding reports our recent progress on this key issue, namely, we obtained a simple analytical functional form for the one-electron renormalisation factors, and introduced a novel sum-rule correction for a more accurate description of the intersite electron correlations. Benchmark calculations are performed on a set of molecules to show the reasonable accuracy of the method.

High-frequency sum rules for classical one-component plasma in a magnetic field

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

Genga, R.O.

A high-frequency sum-rule expansion is derived for all elements of a classical plasma dielectric tensor in the presence of an external magnetic field. Omega/sub 4//sup 13/ is found to be the only coefficient of omega/sup -4/ that has no correlational and finite-radiation-temperature contributions. The finite-radiation-temperature effect results in an upward renormalization of the frequencies of the modes; it also leads to either reduction of the negative correlational effect on the positive thermal dispersion or, together with correlation, enhancement of the positive thermal dispersion for finite k, depending on the direction of propagation. Further, for the extraordinary mode, the finite-radiation-temperature effectmore » increases the positive refractive dispersion for finite k.« less

Masses of Open-Flavour Heavy-Light Hybrids from QCD Sum Rules

NASA Astrophysics Data System (ADS)

Ho, Jason; Harnett, Derek; Steele, Tom

2017-01-01

Our current understanding of the strong interaction (QCD) permits the construction of colour singlet states with novel structures that do not fit within the traditional quark model, including hybrid mesons. To date, though other exotic structures such as pentaquark and tetraquark states have been confirmed, no unambiguous hybrid meson signals have been observed. However, with data collection at the GlueX experiment ongoing and with the construction of the PANDA experiment at FAIR, the opportunity to observe hybrid states has never been better. As theoretical calculations are a necessary piece for the identification of any observed experimental resonance, we present our mass predictions of heavy-light open-flavour hybrid mesons using QCD Laplace sum-rules for all scalar and vector JP channels, and including non-perturbative condensate contributions up to six-dimensions.

Splitting of electrons and violation of the Luttinger sum rule

NASA Astrophysics Data System (ADS)

Quinn, Eoin

2018-03-01

We obtain a controlled description of a strongly correlated regime of electronic behavior. We begin by arguing that there are two ways to characterize the electronic degree of freedom, either by the canonical fermion algebra or the graded Lie algebra su (2 |2 ) . The first underlies the Fermi liquid description of correlated matter, and we identify a regime governed by the latter. We exploit an exceptional central extension of su (2 |2 ) to employ a perturbative scheme recently developed by Shastry and obtain a series of successive approximations for the electronic Green's function. We then focus on the leading approximation, which reveals a splitting in two of the electronic dispersion. The Luttinger sum rule is violated, and a Mott metal-insulator transition is exhibited. We offer a perspective.

Neutron matter within QCD sum rules

NASA Astrophysics Data System (ADS)

Cai, Bao-Jun; Chen, Lie-Wen

2018-05-01

The equation of state (EOS) of pure neutron matter (PNM) is studied in QCD sum rules (QCDSRs ). It is found that the QCDSR results on the EOS of PNM are in good agreement with predictions by current advanced microscopic many-body theories. Moreover, the higher-order density terms in quark condensates are shown to be important to describe the empirical EOS of PNM in the density region around and above nuclear saturation density although they play a minor role at subsaturation densities. The chiral condensates in PNM are also studied, and our results indicate that the higher-order density terms in quark condensates, which are introduced to reasonably describe the empirical EOS of PNM at suprasaturation densities, tend to hinder the appearance of chiral symmetry restoration in PNM at high densities.

Examination of the first excited state of 4He as a potential breathing mode

NASA Astrophysics Data System (ADS)

Bacca, Sonia; Barnea, Nir; Leidemann, Winfried; Orlandini, Giuseppina

2015-02-01

The isoscalar monopole excitation of 4He is studied within a few-body ab initio approach. We consider the transition density to the low-lying and narrow 0+ resonance, as well as various sum rules and the strength energy distribution itself at different momentum transfers q . Realistic nuclear forces of chiral and phenomenological nature are employed. Various indications for a collective breathing mode are found: (i) the specific shape of the transition density, (ii) the high degree of exhaustion of the non-energy-weighted sum rule at low q , and (iii) the complete dominance of the resonance peak in the excitation spectrum. For the incompressibility K of the α particle, two different definitions give two rather small values (22 and 36 MeV).

Analysis of the strong coupling form factors of ΣbNB and ΣcND in QCD sum rules

NASA Astrophysics Data System (ADS)

Yu, Guo-Liang; Wang, Zhi-Gang; Li, Zhen-Yu

2017-08-01

In this article, we study the strong interaction of the vertices Σ b NB and Σ c ND using the three-point QCD sum rules under two different Dirac structures. Considering the contributions of the vacuum condensates up to dimension 5 in the operation product expansion, the form factors of these vertices are calculated. Then, we fit the form factors into analytical functions and extrapolate them into time-like regions, which gives the coupling constants. Our analysis indicates that the coupling constants for these two vertices are G ΣbNB = 0.43±0.01 GeV-1 and G ΣcND = 3.76±0.05 GeV-1. Supported by Fundamental Research Funds for the Central Universities (2016MS133)

Dielectric properties of crystalline organic molecular films in the limit of zero overlap

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

D’Avino, Gabriele, E-mail: gabriele.davino@gmail.com; Vanzo, Davide; Soos, Zoltán G., E-mail: soos@princeton.edu

2016-01-21

We present the calculation of the static dielectric susceptibility tensor and dipole field sums in thin molecular films in the well-defined limit of zero intermolecular overlap. Microelectrostatic and charge redistribution approaches are applied to study the evolution of dielectric properties from one to a few molecular layers in films of different conjugated molecules with organic electronics applications. Because of the conditional convergence of dipolar interactions, dipole fields depend on the shape of the sample and different values are found in the middle layer of a thick film and in the bulk. The shape dependence is eliminated when depolarization is takenmore » into account, and the dielectric tensor of molecular films converges to the bulk limit within a few molecular layers. We quantify the magnitude of surface effects and interpret general trends among different systems in terms of molecular properties, such as shape, polarizability anisotropy, and supramolecular organization. A connection between atomistic models for molecular dielectrics and simpler theories for polarizable atomic lattices is also provided.« less

Collision-induced absorption with exchange effects and anisotropic interactions: theory and application to H2 - H2.

PubMed

Karman, Tijs; van der Avoird, Ad; Groenenboom, Gerrit C

2015-02-28

We discuss three quantum mechanical formalisms for calculating collision-induced absorption spectra. First, we revisit the established theory of collision-induced absorption, assuming distinguishable molecules which interact isotropically. Then, the theory is rederived incorporating exchange effects between indistinguishable molecules. It is shown that the spectrum can no longer be written as an incoherent sum of the contributions of the different spherical components of the dipole moment. Finally, we derive an efficient method to include the effects of anisotropic interactions in the computation of the absorption spectrum. This method calculates the dipole coupling on-the-fly, which allows for the uncoupled treatment of the initial and final states without the explicit reconstruction of the many-component wave functions. The three formalisms are applied to the collision-induced rotation-translation spectra of hydrogen molecules in the far-infrared. Good agreement with experimental data is obtained. Significant effects of anisotropic interactions are observed in the far wing.

Applying electric field to charged and polar particles between metallic plates: extension of the Ewald method.

PubMed

Takae, Kyohei; Onuki, Akira

2013-09-28

We develop an efficient Ewald method of molecular dynamics simulation for calculating the electrostatic interactions among charged and polar particles between parallel metallic plates, where we may apply an electric field with an arbitrary size. We use the fact that the potential from the surface charges is equivalent to the sum of those from image charges and dipoles located outside the cell. We present simulation results on boundary effects of charged and polar fluids, formation of ionic crystals, and formation of dipole chains, where the applied field and the image interaction are crucial. For polar fluids, we find a large deviation of the classical Lorentz-field relation between the local field and the applied field due to pair correlations along the applied field. As general aspects, we clarify the difference between the potential-fixed and the charge-fixed boundary conditions and examine the relationship between the discrete particle description and the continuum electrostatics.

Laser spectroscopy of the 5P3/2 → 6Pj (j = 1/2 and 3/2) electric dipole forbidden transitions in atomic rubidium

NASA Astrophysics Data System (ADS)

Ponciano-Ojeda, F.; Hernández-Gómez, S.; Mojica-Casique, C.; Hoyos, L. M.; Flores-Mijangos, J.; Ramírez-Martínez, F.; Sahagún, D.; Jáuregui, R.; Jiménez-Mier, J.

2018-04-01

Doppler-free optical double-resonance spectroscopy is used to study the 5S1/2 → 5P3/2 → 6Pj (j = 3/2,1/2) excitation sequence in room-temperature rubidium atoms. This involves a 5S1/2 → 5P3/2 electric dipole preparation step followed by the 5P3/2 → 6Pj electric quadrupole excitation. The electric dipole forbidden transitions occur at 911.0 nm (j = 3/2) and 917.5 nm (j = 1/2). Production of atoms in the 6Pj states is detected by observing their direct decay to the ground state through emission of blue photons (λ ≈ 420 nm). A detailed experimental and theoretical study of the dependence on the relative linear polarizations of excitation beams is made. It is shown that specific electric quadrupole selection rules over magnetic quantum numbers are directly related to the relative orientation of the linear polarization of the excitation beams.

Deriving Laws from Ordering Relations

NASA Technical Reports Server (NTRS)

Knuth, Kevin H.

2003-01-01

It took much effort in the early days of non-Euclidean geometry to break away from the mindset that all spaces are flat and that two distinct parallel lines do not cross. Up to that point, all that was known was Euclidean geometry, and it was difficult to imagine anything else. We have suffered a similar handicap brought on by the enormous relevance of Boolean algebra to the problems of our age-logic and set theory. Previously, I demonstrated that the algebra of questions is not Boolean, but rather is described by the free distributive algebra. To get to this stage took much effort, as many obstacles-most self-placed-had to be overcome. As Boolean algebras were all I had ever known, it was almost impossible for me to imagine working with an algebra where elements do not have complements. With this realization, it became very clear that the sum and product rules of probability theory at the most basic level had absolutely nothing to do with the Boolean algebra of logical statements. Instead, a measure of degree of inclusion can be invented for many different partially ordered sets, and the sum and product rules fall out of the associativity and distributivity of the algebra. To reinforce this very important idea, this paper will go over how these constructions are made, while focusing on the underlying assumptions. I will derive the sum and product rules for a distributive lattice in general and demonstrate how this leads to probability theory on the Boolean lattice and is related to the calculus of quantum mechanical amplitudes on the partially ordered set of experimental setups. I will also discuss the rules that can be derived from modular lattices and their relevance to the cross-ratio of projective geometry.

Bilinearity in Spatiotemporal Integration of Synaptic Inputs

PubMed Central

Li, Songting; Liu, Nan; Zhang, Xiao-hui; Zhou, Douglas; Cai, David

2014-01-01

Neurons process information via integration of synaptic inputs from dendrites. Many experimental results demonstrate dendritic integration could be highly nonlinear, yet few theoretical analyses have been performed to obtain a precise quantitative characterization analytically. Based on asymptotic analysis of a two-compartment passive cable model, given a pair of time-dependent synaptic conductance inputs, we derive a bilinear spatiotemporal dendritic integration rule. The summed somatic potential can be well approximated by the linear summation of the two postsynaptic potentials elicited separately, plus a third additional bilinear term proportional to their product with a proportionality coefficient . The rule is valid for a pair of synaptic inputs of all types, including excitation-inhibition, excitation-excitation, and inhibition-inhibition. In addition, the rule is valid during the whole dendritic integration process for a pair of synaptic inputs with arbitrary input time differences and input locations. The coefficient is demonstrated to be nearly independent of the input strengths but is dependent on input times and input locations. This rule is then verified through simulation of a realistic pyramidal neuron model and in electrophysiological experiments of rat hippocampal CA1 neurons. The rule is further generalized to describe the spatiotemporal dendritic integration of multiple excitatory and inhibitory synaptic inputs. The integration of multiple inputs can be decomposed into the sum of all possible pairwise integration, where each paired integration obeys the bilinear rule. This decomposition leads to a graph representation of dendritic integration, which can be viewed as functionally sparse. PMID:25521832

Born’s rule as signature of a superclassical current algebra

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

Fussy, S.; Mesa Pascasio, J.; Institute for Atomic and Subatomic Physics, Vienna University of Technology, Operng. 9, 1040 Vienna

2014-04-15

We present a new tool for calculating the interference patterns and particle trajectories of a double-, three- and N-slit system on the basis of an emergent sub-quantum theory developed by our group throughout the last years. The quantum itself is considered as an emergent system representing an off-equilibrium steady state oscillation maintained by a constant throughput of energy provided by a classical zero-point energy field. We introduce the concept of a “relational causality” which allows for evaluating structural interdependences of different systems levels, i.e. in our case of the relations between partial and total probability density currents, respectively. Combined with themore » application of 21st century classical physics like, e.g., modern nonequilibrium thermodynamics, we thus arrive at a “superclassical” theory. Within this framework, the proposed current algebra directly leads to a new formulation of the guiding equation which is equivalent to the original one of the de Broglie–Bohm theory. By proving the absence of third order interferences in three-path systems it is shown that Born’s rule is a natural consequence of our theory. Considering the series of one-, double-, or, generally, of N-slit systems, with the first appearance of an interference term in the double slit case, we can explain the violation of Sorkin’s first order sum rule, just as the validity of all higher order sum rules. Moreover, the Talbot patterns and Talbot distance for an arbitrary N-slit device can be reproduced exactly by our model without any quantum physics tool. -- Highlights: •Calculating the interference patterns and particle trajectories of a double-, three- and N-slit system. •Deriving a new formulation of the guiding equation equivalent to the de Broglie–Bohm one. •Proving the absence of third order interferences and thus explaining Born’s rule. •Explaining the violation of Sorkin’s order sum rules. •Classical simulation of Talbot patterns and exact reproduction of Talbot distance for N slits.« less

Coupled-cluster sum-frequency generation nonlinear susceptibilities of methyl (CH3) and methylene (CH2) groups.

PubMed

Tetsassi Feugmo, Conrard Giresse; Liégeois, Vincent; Champagne, Benoît

2017-11-15

The first vibrational sum frequency generation (SFG) spectra based on molecular properties calculated at the coupled cluster singles and doubles (CCSD) level of approximation have been simulated for interfacial model alkyl chains, providing benchmark data for comparisons with approximate methods, including density functional theory (DFT). The approach proceeds in three steps. In the first two steps, the molecular spectral properties are determined: the vibrational normal modes and frequencies and then the derivatives of the dipole moment and of the polarizability with respect to the normal coordinates. These derivatives are evaluated with a numerical differentiation approach, of which the accuracy was monitored using Romberg's procedure. Then, in the last step, a three-layer model is employed to evaluate the macroscopic second-order nonlinear optical responses and thereby the simulated SFG spectra of the alkyl interface. Results emphasize the following facts: (i) the dipole and polarizability derivatives calculated at the DFT level with the B3LYP exchange-correlation functional can differ, with respect to CCSD, by as much as ±10 to 20% and ±20 to 50% for the CH 3 and CH 2 vibrations, respectively; (ii) these differences are enhanced when considering the SFG intensities as well as their variations as a function of the experimental configuration (ppp versus ssp) and as a function of the tilt and rotation angles, defining the orientation of the alkyl chain at the interface; (iii) these differences originate from both the vibrational normal coordinates and the Cartesian derivatives of the dipole moment and polarizability; (iv) freezing the successive fragments of the alkyl chain strongly modifies the SFG spectrum and enables highlighting the delocalization effects between the terminal CH 3 group and its neighboring CH 2 units; and finally (v) going from the free chain to the free methyl model, and further to C 3v constraints on leads to large variations of two ratios that are frequently used to probe the molecular orientation at the interface, the (r + r)/r + ratio for both antisymmetric and symmetric CH 3 vibrations and the I ppp /I ssp ratio.

Model of a Negatively Curved Two-Dimensional Space.

ERIC Educational Resources Information Center

Eckroth, Charles A.

1995-01-01

Describes the construction of models of two-dimensional surfaces with negative curvature that are used to illustrate differences in the triangle sum rule for the various Big Bang Theories of the universe. (JRH)

Explosive site percolation with a product rule.

PubMed

Choi, Woosik; Yook, Soon-Hyung; Kim, Yup

2011-08-01

We study the site percolation under Achlioptas process with a product rule in a two-dimensional square lattice. From the measurement of the cluster size distribution P(s), we find that P(s) has a very robust power-law regime followed by a stable hump near the transition threshold. Based on the careful analysis on the PP(s) distribution, we show that the transition should be discontinuous. The existence of the hysteresis loop in order parameter also verifies that the transition is discontinuous in two dimensions. Moreover, we also show that the transition nature from the product rule is not the same as that from a sum rule in two dimensions.

Sum-rule corrections: A route to error cancellations in correlation matrix renormalisation theory

DOE PAGES

Liu, C.; Liu, J.; Yao, Y. X.; ...

2017-01-16

Here, we recently proposed the correlation matrix renormalisation (CMR) theory to efficiently and accurately calculate ground state total energy of molecular systems, based on the Gutzwiller variational wavefunction (GWF) to treat the electronic correlation effects. To help reduce numerical complications and better adapt the CMR to infinite lattice systems, we need to further refine the way to minimise the error originated from the approximations in the theory. This conference proceeding reports our recent progress on this key issue, namely, we obtained a simple analytical functional form for the one-electron renormalisation factors, and introduced a novel sum-rule correction for a moremore » accurate description of the intersite electron correlations. Benchmark calculations are performed on a set of molecules to show the reasonable accuracy of the method.« less

Sum-rule corrections: A route to error cancellations in correlation matrix renormalisation theory

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

Liu, C.; Liu, J.; Yao, Y. X.

Here, we recently proposed the correlation matrix renormalisation (CMR) theory to efficiently and accurately calculate ground state total energy of molecular systems, based on the Gutzwiller variational wavefunction (GWF) to treat the electronic correlation effects. To help reduce numerical complications and better adapt the CMR to infinite lattice systems, we need to further refine the way to minimise the error originated from the approximations in the theory. This conference proceeding reports our recent progress on this key issue, namely, we obtained a simple analytical functional form for the one-electron renormalisation factors, and introduced a novel sum-rule correction for a moremore » accurate description of the intersite electron correlations. Benchmark calculations are performed on a set of molecules to show the reasonable accuracy of the method.« less

Ward identities and combinatorics of rainbow tensor models

NASA Astrophysics Data System (ADS)

Itoyama, H.; Mironov, A.; Morozov, A.

2017-06-01

We discuss the notion of renormalization group (RG) completion of non-Gaussian Lagrangians and its treatment within the framework of Bogoliubov-Zimmermann theory in application to the matrix and tensor models. With the example of the simplest non-trivial RGB tensor theory (Aristotelian rainbow), we introduce a few methods, which allow one to connect calculations in the tensor models to those in the matrix models. As a byproduct, we obtain some new factorization formulas and sum rules for the Gaussian correlators in the Hermitian and complex matrix theories, square and rectangular. These sum rules describe correlators as solutions to finite linear systems, which are much simpler than the bilinear Hirota equations and the infinite Virasoro recursion. Search for such relations can be a way to solving the tensor models, where an explicit integrability is still obscure.

The light-front gauge-invariant energy-momentum tensor

DOE PAGES

Lorce, Cedric

2015-08-11

In this study, we provide for the first time a complete parametrization for the matrix elements of the generic asymmetric, non-local and gauge-invariant canonical energy-momentum tensor, generalizing therefore former works on the symmetric, local and gauge-invariant kinetic energy-momentum tensor also known as the Belinfante-Rosenfeld energy-momentum tensor. We discuss in detail the various constraints imposed by non-locality, linear and angular momentum conservation. We also derive the relations with two-parton generalized and transverse-momentum dependent distributions, clarifying what can be learned from the latter. In particular, we show explicitly that two-parton transverse-momentum dependent distributions cannot provide any model-independent information about the parton orbitalmore » angular momentum. On the way, we recover the Burkardt sum rule and obtain similar new sum rules for higher-twist distributions.« less

Chiral dynamics in the low-temperature phase of QCD

NASA Astrophysics Data System (ADS)

Brandt, Bastian B.; Francis, Anthony; Meyer, Harvey B.; Robaina, Daniel

2014-09-01

We investigate the low-temperature phase of QCD and the crossover region with two light flavors of quarks. The chiral expansion around the point (T,m=0) in the temperature vs quark-mass plane indicates that a sharp real-time excitation exists with the quantum numbers of the pion. An exact sum rule is derived for the thermal modification of the spectral function associated with the axial charge density; the (dominant) pion pole contribution obeys the sum rule. We determine the two parameters of the pion dispersion relation using lattice QCD simulations and test the applicability of the chiral expansion. The time-dependent correlators are also analyzed using the maximum entropy method, yielding consistent results. Finally, we test the predictions of the chiral expansion around the point (T=0,m=0) for the temperature dependence of static observables.

Spin dependent structure function g1 of the deuteron and the proton

NASA Astrophysics Data System (ADS)

Klostermann, L.

1995-05-01

This thesis presents a study on the spin structure of the nucleon, via deep inelastic scattering (DIS) of polarized muons on polarized proton and deuterium targets. The work was done in the Spin Muon Collaboration (SMC) at CERN in Geneva. From the asymmetry in the scattering cross section for nucleon and lepton spins parallel and anti-parallel, one can determine the spin dependent structure function g(sub 1), which contains information on the quark and gluon spin distribution functions. The interpretation in the frame work of the quark parton model (QPM) of earlier results on g(sub 1, sup d) by the European Muon Collaboration (EMC), gave an indication that only a small fraction of the proton spin, compatible with zero, is carried by the spins of the constituent quarks. The SMC was set up to check this unexpected result with improved accuracy, and to combine measurements of g(sub 1, sup p) and g(sub 1, sup d) to test a fundamental sum rule in quantum chromodynamics (QCD), the Bjorken sum rule. The SMC results presented in this thesis are based on data taken in 1992 using a polarized deuterium target and polarized muons with an incident energy of 100 GeV, and 1993 data with a proton target and an incident muon energy of 190 GeV. Using all available data, the fundamental Bjorken sum rule has now been verified at the one standard deviation level to within 16% of its theoretical value.

Energy of charged states in the acetanilide crystal: Trapping of charge-transfer states at vacancies as a possible mechanism for optical damage

NASA Astrophysics Data System (ADS)

Tsiaousis, D.; Munn, R. W.

2004-04-01

Calculations for the acetanilide crystal yield the effective polarizability (16.6 Å3), local electric field tensor, effective dipole moment (5.41 D), and dipole-dipole energy (-12.8 kJ/mol). Fourier-transform techniques are used to calculate the polarization energy P for a single charge in the perfect crystal (-1.16 eV); the charge-dipole energy WD is zero if the crystal carries no bulk dipole moment. Polarization energies for charge-transfer (CT) pairs combine with the Coulomb energy EC to give the screened Coulomb energy Escr; screening is nearly isotropic, with Escr≈EC/2.7. For CT pairs WD reduces to a term δWD arising from the interaction of the charge on each ion with the change in dipole moment on the other ion relative to the neutral molecule. The dipole moments calculated by density-functional theory methods with the B3LYP functional at the 6-311++G** level are 3.62 D for the neutral molecule, changing to 7.13 D and 4.38 D for the anion and cation, relative to the center of mass. Because of the large change in the anion, δWD reaches -0.9 eV and modifies the sequence of CT energies markedly from that of Escr, giving the lowest two CT pairs at -1.98 eV and -1.41 eV. The changes in P and WD near a vacancy are calculated; WD changes for the individual charges because the vacancy removes a dipole moment and modifies the crystal dielectric response, but δWD and EC do not change. A vacancy yields a positive change ΔP that scatters a charge or CT pair, but the change ΔWD can be negative and large enough to outweigh ΔP, yielding traps with depths that can exceed 150 meV for single charges and for CT pairs. Divacancies yield traps with depths nearly equal to the sum of those produced by the separate vacancies and so they can exceed 300 meV. These results are consistent with a mechanism of optical damage in which vacancies trap optically generated CT pairs that recombine and release energy; this can disrupt the lattice around the vacancy, thereby favoring trapping and recombination of CT pairs generated by subsequent photon absorption, leading to further lattice disruption. Revisions to previous calculations on trapping of CT pairs in anthracene are reported.

Coupling of Molecular Emitters and Plasmonic Cavities beyond the Point-Dipole Approximation.

PubMed

Neuman, Tomáš; Esteban, Ruben; Casanova, David; García-Vidal, Francisco J; Aizpurua, Javier

2018-04-11

As the size of a molecular emitter becomes comparable to the dimensions of a nearby optical resonator, the standard approach that considers the emitter to be a point-like dipole breaks down. By adoption of a quantum description of the electronic transitions of organic molecular emitters, coupled to a plasmonic electromagnetic field, we are able to accurately calculate the position-dependent coupling strength between a plasmon and an emitter. The spatial distribution of excitonic and photonic quantum states is found to be a key aspect in determining the dynamics of molecular emission in ultrasmall cavities both in the weak and strong coupling regimes. Moreover, we show that the extreme localization of plasmonic fields leads to the selection rule breaking of molecular excitations.

Electric dipole spin resonance in a quantum spin dimer system driven by magnetoelectric coupling

NASA Astrophysics Data System (ADS)

Kimura, Shojiro; Matsumoto, Masashige; Akaki, Mitsuru; Hagiwara, Masayuki; Kindo, Koichi; Tanaka, Hidekazu

2018-04-01

In this Rapid Communication, we propose a mechanism for electric dipole active spin resonance caused by spin-dependent electric polarization in a quantum spin gapped system. This proposal was successfully confirmed by high-frequency electron spin resonance (ESR) measurements of the quantum spin dimer system KCuCl3. ESR measurements by an illuminating linearly polarized electromagnetic wave reveal that the optical transition between the singlet and triplet states in KCuCl3 is driven by an ac electric field. The selection rule of the observed transition agrees with the calculation by taking into account spin-dependent electric polarization. We suggest that spin-dependent electric polarization is effective in achieving fast control of quantum spins by an ac electric field.

Department of Defense Youth Poll Wave 9 - June 2005. Overview Report

DTIC Science & Technology

2006-01-01

Saving Private Ryan ,” “A...A*S*H 20 MEN OF HONOR 21 PEARL HARBOR 22 PLATOON 23 RAMBO SERIES (FIRST BLOOD, RAMBO 2, RAMBO 3) 24 RULES OF ENGAGEMENT 25 SAVING PRIVATE RYAN 26...RAMBO 2, RAMBO 3) 24 RULES OF ENGAGEMENT 25 SAVING PRIVATE RYAN 26 SUM OF ALL FEARS 27 A THIN RED LINE 28 THREE KINGS 29 TORA! TORA! TORA!

Intraband magneto-optical absorption in InAs/GaAs quantum dots: Orbital Zeeman splitting and the Thomas-Reiche-Kuhn sum rule

NASA Astrophysics Data System (ADS)

Zhang, J.-Z.; Galbraith, I.

2008-05-01

Using perturbation theory, intraband magneto-optical absorption is calculated for InAs/GaAs truncated pyramidal quantum dots in a magnetic field applied parallel to the growth direction z . The effects of the magnetic field on the electronic states as well as the intraband transitions are systematically studied. Selection rules governing the intraband transitions are discussed based on the symmetry properties of the electronic states. While the broadband z -polarized absorption is almost insensitive to the magnetic field, the orbital Zeeman splitting is the dominant feature in the in-plane polarized spectrum. Strong in-plane polarized magneto-absorption features are located in the far-infrared region, while z -polarized absorption occurs at higher frequencies. This is due to the dot geometry (the base length is much larger than the height) yielding different quantum confinement in the vertical and lateral directions. The Thomas-Reiche-Kuhn sum rule, including the magnetic field effect, is applied together with the selection rules to the absorption spectra. The orbital Zeeman splitting depends on both the dot size and the confining potential—the splitting decreases as the dot size or the confining potential decreases. Our calculated Zeeman splittings are in agreement with experimental data.

Experimental determination of the effective strong coupling constant

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

Alexandre Deur; Volker Burkert; Jian-Ping Chen

2007-07-01

We extract an effective strong coupling constant from low Q{sup 2} data on the Bjorken sum. Using sum rules, we establish its Q{sup 2}-behavior over the complete Q{sup 2}-range. The result is compared to effective coupling constants extracted from different processes and to calculations based on Schwinger-Dyson equations, hadron spectroscopy or lattice QCD. Although the connection between the experimentally extracted effective coupling constant and the calculations is not clear, the results agree surprisingly well.

Simple Physics-Based Analytical Formulas for the Potentials of Mean Force of the Interaction of Amino Acid Side Chains in Water. VII. Charged-Hydrophobic/Polar and Polar-Hydrophobic/Polar Side Chains.

PubMed

Makowski, Mariusz; Liwo, Adam; Scheraga, Harold A

2017-01-19

The physics-based potentials of side-chain-side-chain interactions corresponding to pairs composed of charged and polar, polar and polar, charged and hydrophobic, and hydrophobic and hydrophobic side chains have been determined. A total of 144 four-dimensional potentials of mean force (PMFs) of all possible pairs of molecules modeling these pairs were determined by umbrella-sampling molecular dynamics simulations in explicit water as functions of distance and orientation, and the analytical expressions were then fitted to the PMFs. Depending on the type of interacting sites, the analytical approximation to the PMF is a sum of terms corresponding to van der Waals interactions and cavity-creation involving the nonpolar sections of the side chains and van der Waals, cavity-creation, and electrostatic (charge-dipole or dipole-dipole) interaction energies and polarization energies involving the charged or polar sections of the side chains. The model used in this work reproduces all features of the interacting pairs. The UNited RESidue force field with the new side-chain-side-chain interaction potentials was preliminarily tested with the N-terminal part of the B-domain of staphylococcal protein A (PDBL 1BDD ; a three-α-helix bundle) and UPF0291 protein YnzC from Bacillus subtilis (PDB: 2HEP ; an α-helical hairpin).

Novel approach for calculating the charge carrier mobility and Hall factor for semiconductor materials

NASA Astrophysics Data System (ADS)

Colibaba, G. V.

2018-06-01

The additive Matthiessen's rule is the simplest and most widely used rule for the rapid experimental characterization and modeling of the charge carrier mobility. However, the error when using this rule can be higher than 40% and the contribution of the assumed additional scattering channels due to the difference between the experimental data and results calculated based on this rule can be misestimated by several times. In this study, a universal semi-additive equation is proposed for the total mobility and Hall factor, which is applicable to any quantity of scattering mechanisms, where it considers the energy dependence of the relaxation time and the error is 10-20 times lower compared with Matthiessen's rule. Calculations with accuracy of 99% are demonstrated for materials with polar-optical phonon, acoustic phonon via the piezoelectric potential, ionized, and neutral impurity scattering. The proposed method is extended to the deformation potential, dislocation, localized defect, alloy potential, and dipole scattering, for nondegenerate and partially degenerate materials.

Differential phase measurements of D-region partial reflections

NASA Technical Reports Server (NTRS)

Wiersma, D. J.; Sechrist, C. F., Jr.

1972-01-01

Differential phase partial reflection measurements were used to deduce D region electron density profiles. The phase difference was measured by taking sums and differences of amplitudes received on an array of crossed dipoles. The reflection model used was derived from Fresnel reflection theory. Seven profiles obtained over the period from 13 October 1971 to 5 November 1971 are presented, along with the results from simultaneous measurements of differential absorption. Some possible sources of error and error propagation are discussed. A collision frequency profile was deduced from the electron concentration calculated from differential phase and differential absorption.

Inelastic losses in X-ray absorption theory

NASA Astrophysics Data System (ADS)

Campbell, Luke Whalin

There is a surprising lack of many body effects observed in XAS (X-ray Absorption Spectroscopy) experiments. While collective excitations and other satellite effects account for between 20% and 40% of the spectral weight of the core hole and photoelectron excitation spectrum, the only commonly observed many body effect is a relatively structureless amplitude reduction to the fine structure, typically no more than a 10% effect. As a result, many particle effects are typically neglected in the XAS codes used to predict and interpret modern experiments. To compensate, the amplitude reduction factor is simply fitted to experimental data. In this work, a quasi-boson model is developed to treat the case of XAS, when the system has both a photoelectron and a core hole. We find that there is a strong interference between the extrinsic and intrinsic losses. The interference reduces the excitation amplitudes at low energies where the core hole and photo electron induced excitations tend to cancel. At high energies, the interference vanishes, and the theory reduces to the sudden approximation. The x-ray absorption spectrum including many-body excitations is represented by a convolution of the one-electron absorption spectrum with an energy dependent spectral function. The latter has an asymmetric quasiparticle peak and broad satellite structure. The net result is a phasor sum, which yields the many body amplitude reduction and phase shift of the fine structure oscillations (EXAFS), and possibly additional satellite structure. Calculations for several cases of interest are found to be in reasonable agreement with experiment. Edge singularity effects and deviations from the final state rule arising from this theory are also discussed. The ab initio XAS code FEFF has been extended for calculations of the many body amplitude reduction and phase shift in x-ray spectroscopies. A new broadened plasmon pole self energy is added. The dipole matrix elements are modified to include a projection operator to calculate deviations from the final state rule and edge singularities.

Concise NMR approach for molecular dynamics characterizations in organic solids.

PubMed

Aliev, Abil E; Courtier-Murias, Denis

2013-08-22

Molecular dynamics characterisations in solids can be carried out selectively using dipolar-dephasing experiments. Here we show that the introduction of a sum of Lorentzian and Gaussian functions greatly improve fittings of the "intensity versus time" data for protonated carbons in dipolar-dephasing experiments. The Lorentzian term accounts for remote intra- and intermolecular (1)H-(13)C dipole-dipole interactions, which vary from one molecule to another or for different carbons within the same molecule. Thus, by separating contributions from weak remote interactions, more accurate Gaussian decay constants, T(dd), can be extracted for directly bonded (1)H-(13)C dipole-dipole interactions. Reorientations of the (1)H-(13)C bonds lead to the increase of T(dd), and by measuring dipolar-dephasing constants, insight can be gained into dynamics in solids. We have demonstrated advantages of the method using comparative dynamics studies in the α and γ polymorphs of glycine, cyclic amino acids L-proline, DL-proline and trans-4-hydroxy-L-proline, the Ala residue in different dipeptides, as well as adamantane and hexamethylenetetramine. It was possible to distinguish subtle differences in dynamics of different carbon sites within a molecule in polymorphs and in L- and DL-forms. The presence of overall molecular motions is shown to lead to particularly large differences in dipolar-dephasing experiments. The differences in dynamics can be attributed to differences in noncovalent interactions. In the case of hexamethylenetetramine, for example, the presence of C-H···N interactions leads to nearly rigid molecules. Overall, the method allows one to gain insight into the role of noncovalent interactions in solids and their influence on the molecular dynamics.

Theory of pure rotational transitions in doubly degenerate torsional states of ethane

NASA Technical Reports Server (NTRS)

Rosenberg, A.; Susskind, J.

1979-01-01

It is shown that pure rotational transitions in doubly degenerate torsional states of C2H6 (with selection rules Delta K = 0, plus or minus 1) are made allowed by Coriolis interaction between torsion and dipole-allowed vibrations. Expressions are presented for integrated intensities from which strengths of lines in the millimeter region can be calculated.

Communication. Kinetics of scavenging of small, nucleating clusters. First nucleation theorem and sum rules

DOE PAGES

Malila, Jussi; McGraw, Robert; Laaksonen, Ari; ...

2015-01-07

Despite recent advances in monitoring nucleation from a vapor at close-to-molecular resolution, the identity of the critical cluster, forming the bottleneck for the nucleation process, remains elusive. During past twenty years, the first nucleation theorem has been often used to extract the size of the critical cluster from nucleation rate measurements. However, derivations of the first nucleation theorem invoke certain questionable assumptions that may fail, e.g., in the case of atmospheric new particle formation, including absence of subcritical cluster losses and heterogeneous nucleation on pre-existing nanoparticles. Here we extend the kinetic derivation of the first nucleation theorem to give amore » general framework to include such processes, yielding sum rules connecting the size dependent particle formation and loss rates to the corresponding loss-free nucleation rate and the apparent critical size from a naïve application of the first nucleation theorem that neglects them.« less

Effects of plasmon pole models on the G0W0 electronic structure of various oxides

NASA Astrophysics Data System (ADS)

Miglio, A.; Waroquiers, D.; Antonius, G.; Giantomassi, M.; Stankovski, M.; Côté, M.; Gonze, X.; Rignanese, G.-M.

2012-09-01

The electronic properties of three different oxides (ZnO, SnO2 and SiO2) are investigated within many-body perturbation theory in the G 0 W 0 approximation. The frequency dependence of the dielectric function is either approximated using two different well-established plasmon-pole models (one of which enforces the fulfillment of the f-sum rule) or treated explicitly by means of the contour-deformation approach. Comparing these results, it is found that the plasmon-pole model enforcing the f-sum rule gives less accurate results for all three oxides. The calculated electronic properties are also compared with the available experimental data and previous ab initio results, focusing on the d state binding energies. The G 0 W 0 approach leads to significantly improved band gaps with respect to calculations based on the density functional theory in the local density approximation.

TOPICS IN THEORY OF GENERALIZED PARTON DISTRIBUTIONS

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

Radyushkin, Anatoly V.

Several topics in the theory of generalized parton distributions (GPDs) are reviewed. First, we give a brief overview of the basics of the theory of generalized parton distributions and their relationship with simpler phenomenological functions, viz. form factors, parton densities and distribution amplitudes. Then, we discuss recent developments in building models for GPDs that are based on the formalism of double distributions (DDs). A special attention is given to a careful analysis of the singularity structure of DDs. The DD formalism is applied to construction of a model GPDs with a singular Regge behavior. Within the developed DD-based approach, wemore » discuss the structure of GPD sum rules. It is shown that separation of DDs into the so-called ``plus'' part and the $D$-term part may be treated as a renormalization procedure for the GPD sum rules. This approach is compared with an alternative prescription based on analytic regularization.« less

Gottfried Sum Rule in QCD Nonsinglet Analysis of DIS Fixed-Target Data

NASA Astrophysics Data System (ADS)

Kotikov, A. V.; Krivokhizhin, V. G.; Shaikhatdenov, B. G.

2018-03-01

Deep-inelastic-scattering data from fixed-target experiments on the structure function F 2 were analyzed in the valence-quark approximation at the next-to-next-to-leading-order accuracy level in the strong-coupling constant. In this analysis, parton distributions were parametrized by employing information from the Gottfried sum rule. The strong-coupling constant was found to be α s ( M 2 Z) = 0.1180 ± 0.0020 (total expt. error), which is in perfect agreement with the world-averaged value from an updated Particle Data Group (PDG) report, α PDG s ( M 2 Z) = 0.1181 ± 0.0011. Also, the value of < x> u- d = 0.187 ± 0.021 found for the second moment of the difference in the u- and d-quark distributions complies very well with the most recent lattice result < x>LATTICE u- d = 0.208 ± 0.024.

The analytical {\\mathscr{O}}({a}_{s}^{4}) expression for the polarized Bjorken sum rule in the miniMOM scheme and the consequences for the generalized Crewther relation

NASA Astrophysics Data System (ADS)

Kataev, A. L.; Molokoedov, V. S.

2017-12-01

The analytical {\\mathscr{O}}({a}s4) perturbative QCD expression for the flavour non-singlet contribution to the Bjorken polarized sum rule in the rather applicable at present gauge-dependent miniMOM scheme is obtained. For the considered three values of the gauge parameter, namely ξ = 0 (Landau gauge), ξ = -1 (anti-Feynman gauge) and ξ = -3 (Stefanis-Mikhailov gauge), the scheme-dependent coefficients are considerably smaller than the gauge-independent {\\overline{{MS}}} results. It is found that the fundamental property of the factorization of the QCD renormalization group β-function in the generalized Crewther relation, which is valid in the gauge-invariant {\\overline{{MS}}} scheme up to {\\mathscr{O}}({a}s4)-level at least, is unexpectedly valid at the same level in the miniMOM-scheme for ξ = 0, and for ξ = -1 and ξ = -3 in part.

Light-cone distribution amplitudes of {xi} and their applications

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

Liu Yonglu; Huang Mingqiu

We present the light-cone distribution amplitudes of the {xi} baryons up to twist six on the basis of QCD conformal partial wave expansion to the leading order conformal spin accuracy. The nonperturbative parameters relevant to the DAs are determined in the framework of the QCD sum rule. The light-cone QCD sum rule approach is used to investigate both the electromagnetic form factors of {xi} and the exclusive semileptonic decay of {xi}{sub c} as applications. Our estimations on the magnetic moments are {mu}{sub {xi}{sup 0}}=-(1.92{+-}0.34){mu}{sub N} and {mu}{sub {xi}{sup -}}=-(1.19{+-}0.03){mu}{sub N}. The decay width of the process {xi}{sub c}{yields}{xi}e{sup +}{nu}{sub e}more » is evaluated to be {gamma}=8.73x10{sup -14} GeV, which is in accordance with the experimental measurements and other theoretical approaches.« less

Study of optical and electronic properties of nickel from reflection electron energy loss spectra

NASA Astrophysics Data System (ADS)

Xu, H.; Yang, L. H.; Da, B.; Tóth, J.; Tőkési, K.; Ding, Z. J.

2017-09-01

We use the classical Monte Carlo transport model of electrons moving near the surface and inside solids to reproduce the measured reflection electron energy-loss spectroscopy (REELS) spectra. With the combination of the classical transport model and the Markov chain Monte Carlo (MCMC) sampling of oscillator parameters the so-called reverse Monte Carlo (RMC) method was developed, and used to obtain optical constants of Ni in this work. A systematic study of the electronic and optical properties of Ni has been performed in an energy loss range of 0-200 eV from the measured REELS spectra at primary energies of 1000 eV, 2000 eV and 3000 eV. The reliability of our method was tested by comparing our results with the previous data. Moreover, the accuracy of our optical data has been confirmed by applying oscillator strength-sum rule and perfect-screening-sum rule.

Integrated layout based Monte-Carlo simulation for design arc optimization

NASA Astrophysics Data System (ADS)

Shao, Dongbing; Clevenger, Larry; Zhuang, Lei; Liebmann, Lars; Wong, Robert; Culp, James

2016-03-01

Design rules are created considering a wafer fail mechanism with the relevant design levels under various design cases, and the values are set to cover the worst scenario. Because of the simplification and generalization, design rule hinders, rather than helps, dense device scaling. As an example, SRAM designs always need extensive ground rule waivers. Furthermore, dense design also often involves "design arc", a collection of design rules, the sum of which equals critical pitch defined by technology. In design arc, a single rule change can lead to chain reaction of other rule violations. In this talk we present a methodology using Layout Based Monte-Carlo Simulation (LBMCS) with integrated multiple ground rule checks. We apply this methodology on SRAM word line contact, and the result is a layout that has balanced wafer fail risks based on Process Assumptions (PAs). This work was performed at the IBM Microelectronics Div, Semiconductor Research and Development Center, Hopewell Junction, NY 12533

One step beyond the electric dipole approximation: An experiment to observe the 5p → 6p forbidden transition in atomic rubidium

NASA Astrophysics Data System (ADS)

Ponciano-Ojeda, F.; Hernández-Gómez, S.; Mojica-Casique, C.; Ruiz-Martínez, E.; López-Hernández, O.; Colín-Rodríguez, R.; Ramírez-Martínez, F.; Flores-Mijangos, J.; Sahagún, D.; Jáuregui, R.; Jiménez-Mier, J.

2018-01-01

An advanced undergraduate experiment to study the 5 P 3 / 2 → 6 P 3 / 2 electric quadrupole transition in rubidium atoms is presented. The experiment uses two external cavity diode lasers, one operating at the D2 rubidium resonance line and the other built with commercial parts to emit at 911 nm. The lasers produce the 5 s → 5 p → 6 p excitation sequence in which the second step is the forbidden transition. Production of atoms in the 6 P 3 / 2 state is observed by detection of the 420 nm fluorescence that results from electric dipole decay into the ground state. Lines whose widths are significantly narrower than the Doppler width are used to study the hyperfine structure of the 6 P 3 / 2 state in rubidium. The spectra illustrate characteristics unique to electric dipole forbidden transitions, like the electric quadrupole selection rules; they are also used to show general aspects of two-color laser spectroscopy such as velocity selection and hyperfine pumping.

Object attributes combine additively in visual search.

PubMed

Pramod, R T; Arun, S P

2016-01-01

We perceive objects as containing a variety of attributes: local features, relations between features, internal details, and global properties. But we know little about how they combine. Here, we report a remarkably simple additive rule that governs how these diverse object attributes combine in vision. The perceived dissimilarity between two objects was accurately explained as a sum of (a) spatially tuned local contour-matching processes modulated by part decomposition; (b) differences in internal details, such as texture; (c) differences in emergent attributes, such as symmetry; and (d) differences in global properties, such as orientation or overall configuration of parts. Our results elucidate an enduring question in object vision by showing that the whole object is not a sum of its parts but a sum of its many attributes.

Toward ab initio molecular dynamics modeling for sum-frequency generation spectra; an efficient algorithm based on surface-specific velocity-velocity correlation function.

PubMed

Ohto, Tatsuhiko; Usui, Kota; Hasegawa, Taisuke; Bonn, Mischa; Nagata, Yuki

2015-09-28

Interfacial water structures have been studied intensively by probing the O-H stretch mode of water molecules using sum-frequency generation (SFG) spectroscopy. This surface-specific technique is finding increasingly widespread use, and accordingly, computational approaches to calculate SFG spectra using molecular dynamics (MD) trajectories of interfacial water molecules have been developed and employed to correlate specific spectral signatures with distinct interfacial water structures. Such simulations typically require relatively long (several nanoseconds) MD trajectories to allow reliable calculation of the SFG response functions through the dipole moment-polarizability time correlation function. These long trajectories limit the use of computationally expensive MD techniques such as ab initio MD and centroid MD simulations. Here, we present an efficient algorithm determining the SFG response from the surface-specific velocity-velocity correlation function (ssVVCF). This ssVVCF formalism allows us to calculate SFG spectra using a MD trajectory of only ∼100 ps, resulting in the substantial reduction of the computational costs, by almost an order of magnitude. We demonstrate that the O-H stretch SFG spectra at the water-air interface calculated by using the ssVVCF formalism well reproduce those calculated by using the dipole moment-polarizability time correlation function. Furthermore, we applied this ssVVCF technique for computing the SFG spectra from the ab initio MD trajectories with various density functionals. We report that the SFG responses computed from both ab initio MD simulations and MD simulations with an ab initio based force field model do not show a positive feature in its imaginary component at 3100 cm(-1).

A quantum mechanical analysis of the light-harvesting complex 2 (LH2) from purple photosynthetic bacteria: insights into the electrostatic effects of transmembrane helices.

PubMed

Pichierri, Fabio

2011-02-01

We perform a quantum mechanical study of the peptides that are part of the LH2 complex from Rhodopseudomonas acidophila, a non-sulfur purple bacteria that has the ability of producing chemical energy from photosynthesis. The electronic structure calculations indicate that the transmembrane helices of these peptides are characterized by dipole moments with a magnitude of about 150D. When the full nonamer assembly made of 18 peptides is considered, then a macrodipole of magnitude 806D is built up from the vector sum of each monomer dipole. The macrodipole is oriented normal to the membrane plane and with the positive tip toward the cytoplasm thereby indicating that the electronic charge of the protein scaffold is polarized toward the periplasm. The results obtained here suggest that the asymmetric charge distribution of the protein scaffold contributes an anisotropic electrostatic environment which differentiates the absorption properties of the bacteriochlorophyll pigments, B800 and B850, embedded in the LH2 complex. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Counterion effects in protein nanoparticle electrostatic binding: a theoretical study.

PubMed

Ghosh, Goutam

2015-04-01

Effects of counterions on the folding conformation of proteins, bound electrostatically on the surface of charge-ligand functionalized nanoparticles, have been investigated based on the protein folding energy calculation. The folding energy of a protein has been taken as a sum of the short range interaction energies, like, the van der Waals attraction and the hydrogen bond energies, and the long range coulomb interaction energy. On electrostatic binding, counterions associated with surface ligands of nanoparticles diffuse into bound proteins through the medium of dispersion. As a result, bound proteins partially unfold, as observed in circular dichroism experiments, which has been realized using the "charge-dipole" and the "charge-induced dipole" interactions of counterions with polar and non-polar residues, respectively. The effect of counterions solvation in the dispersing medium, e.g., water, which causes water molecules to polarize around the counterions, has also been considered. The folding energy of bound proteins has been seen to decrease proportionally with the increasing number of diffusion of counterions and their polarizability. Copyright © 2015 Elsevier B.V. All rights reserved.

Department of Defense Influencer Poll Wave 4 - June 2005. Overview Report

DTIC Science & Technology

2005-12-01

source of their military impressions, but the most frequently mentioned movies include: “ Saving Private Ryan ”, “A Few Good Men”, “Band of Brothers...RAMBO 2, RAMBO 3) 24 RULES OF ENGAGEMENT 25 SAVING PRIVATE RYAN 26 SUM OF ALL FEARS 27 A THIN RED LINE 28 THREE KINGS 29 TORA! TORA! TORA... PRIVATE RYAN 26 SUM OF ALL FEARS 27 A THIN RED LINE 28 THREE KINGS 29 TORA! TORA! TORA! 30 TOP GUN 31 U-571 32 WAG THE DOG 33 WE WERE

Two heads are better than one, but how much? Evidence that people's use of causal integration rules does not always conform to normative standards.

PubMed

Vadillo, Miguel A; Ortega-Castro, Nerea; Barberia, Itxaso; Baker, A G

2014-01-01

Many theories of causal learning and causal induction differ in their assumptions about how people combine the causal impact of several causes presented in compound. Some theories propose that when several causes are present, their joint causal impact is equal to the linear sum of the individual impact of each cause. However, some recent theories propose that the causal impact of several causes needs to be combined by means of a noisy-OR integration rule. In other words, the probability of the effect given several causes would be equal to the sum of the probability of the effect given each cause in isolation minus the overlap between those probabilities. In the present series of experiments, participants were given information about the causal impact of several causes and then they were asked what compounds of those causes they would prefer to use if they wanted to produce the effect. The results of these experiments suggest that participants actually use a variety of strategies, including not only the linear and the noisy-OR integration rules, but also averaging the impact of several causes.

Application of a Novel Diagnostic Rule in the Differential Diagnosis between Acute Gouty Arthritis and Septic Arthritis.

PubMed

Lee, Kwang-Hoon; Choi, Sang-Tae; Lee, Soo-Kyung; Lee, Joo-Hyun; Yoon, Bo-Young

2015-06-01

Septic arthritis and gout are major diseases that should be suspected in patients with acute monoarthritis. These two diseases are clinically similar and often indistinguishable without the help of synovial fluid analysis. Recently, a novel diagnostic rule for gout without synovial fluid analysis was developed and showed relevant performances. This study aimed to determine whether this diagnostic rule could perform well in distinguishing gout from septic arthritis. The diagnostic rule comprises 7 clinical and laboratory variables, each of which is given a specified score. The probability of gout is classified into 3 groups according to the sum of the scores: high (≥ 8), intermediate (> 4 to < 8) and low probability (≤ 4). In this retrospective study, we applied this diagnostic rule to 136 patients who presented as acute monoarthritis and were subsequently diagnosed as acute gout (n = 82) and septic arthritis (n = 54) based on synovial fluid analysis. The mean sum of scores of acute gout patients was significantly higher than that of those with septic arthritis (8.6 ± 0.2 vs. 3.6 ± 0.32, P < 0.001). Patients with acute gout had significantly more 'high', and less 'low' probabilities compared to those with septic arthritis (Eta[η]: 0.776). The prevalence of acute gouty arthritis, as confirmed by the presence of monosodium crystal, was 95.5% (61/64), 57.5% (19/33), and 5.1% (2/39) in high, intermediate and low probability group, respectively. The recently introduced diagnostic rule properly discriminates acute gout from septic arthritis. It may help physicians diagnose gout in cases difficult to be differentiated from septic arthritis.

Energy of charged states in the acetanilide crystal: trapping of charge-transfer states at vacancies as a possible mechanism for optical damage.

PubMed

Tsiaousis, D; Munn, R W

2004-04-15

Calculations for the acetanilide crystal yield the effective polarizability (16.6 A(3)), local electric field tensor, effective dipole moment (5.41 D), and dipole-dipole energy (-12.8 kJ/mol). Fourier-transform techniques are used to calculate the polarization energy P for a single charge in the perfect crystal (-1.16 eV); the charge-dipole energy W(D) is zero if the crystal carries no bulk dipole moment. Polarization energies for charge-transfer (CT) pairs combine with the Coulomb energy E(C) to give the screened Coulomb energy E(scr); screening is nearly isotropic, with E(scr) approximately E(C)/2.7. For CT pairs W(D) reduces to a term deltaW(D) arising from the interaction of the charge on each ion with the change in dipole moment on the other ion relative to the neutral molecule. The dipole moments calculated by density-functional theory methods with the B3LYP functional at the 6-311++G(**) level are 3.62 D for the neutral molecule, changing to 7.13 D and 4.38 D for the anion and cation, relative to the center of mass. Because of the large change in the anion, deltaW(D) reaches -0.9 eV and modifies the sequence of CT energies markedly from that of E(scr), giving the lowest two CT pairs at -1.98 eV and -1.41 eV. The changes in P and W(D) near a vacancy are calculated; W(D) changes for the individual charges because the vacancy removes a dipole moment and modifies the crystal dielectric response, but deltaW(D) and E(C) do not change. A vacancy yields a positive change DeltaP that scatters a charge or CT pair, but the change DeltaW(D) can be negative and large enough to outweigh DeltaP, yielding traps with depths that can exceed 150 meV for single charges and for CT pairs. Divacancies yield traps with depths nearly equal to the sum of those produced by the separate vacancies and so they can exceed 300 meV. These results are consistent with a mechanism of optical damage in which vacancies trap optically generated CT pairs that recombine and release energy; this can disrupt the lattice around the vacancy, thereby favoring trapping and recombination of CT pairs generated by subsequent photon absorption, leading to further lattice disruption. Revisions to previous calculations on trapping of CT pairs in anthracene are reported. (c) 2004 American Institute of Physics.

The Effects of Ion heating in Martian Magnetic Crustal Fields: Particle Tracing and Ion Distributions

NASA Astrophysics Data System (ADS)

Fowler, C. M.; Andersson, L.

2014-12-01

Ion heating is a process that may allow low energy ions within the Martian ionosphere to be accelerated and escape. Ion heating can be especially efficient if the ions stay in the heating region for long time durations. With this in mind, the magnetic crustal field regions on Mars are particularly interesting. We focus on ions present within these regions, where changes in magnetic field strength and direction can heat these ions. Since crustal magnetic fields can maintain a trapped particle population it is unclear how efficiently plasma can be built up that can later escape to space. We investigate here two drivers: rotation of the planet and the solar wind pressure. As crustal fields rotate from the wake of the planet to the sub solar point and back, they experience compression and expansion over time scales of ~24 hours. The solar wind pressure on the other hand can cause variations over much shorter time scales (minutes). The effect of these two drivers using a particle tracing simulation that solves the Lorentz force is presented. O+ ions are seeded within the simulation box. The magnetic environment is a linear sum of a dipole field and a solar wind magnetic field. The dipole field represents the magnetic crustal field and the dipole strength is chosen to be consistent with MGS magnetometer observations of Martian crustal field regions. By increasing the solar wind strength the magnetic dipole is compressed. Decreasing solar wind strength allows the dipole to expand. Small magnitude, short time scale variations can be imposed over the top of this larger variation to represent short time scale solar wind variations. Since the purpose of this analysis is to understand the changes of the ion distribution inside the crustal field, simplistic assumptions of the field outside the crustal field can be made. Initial results are presented, with the focus on two main questions: (a) can low energy ions be heated and escape the closed dipole field lines as a result of varying magnetic fields; (b) is the compression and relaxation of the crustal field due to rotation important for the oxygen escape rates when compared to the particle evolution due to high frequency changes in magnetic field and the lifetimes of these ions.

Temporal evolution of near-surface chlorophyll over cyclonic eddy lifecycles in the southeastern Pacific

NASA Astrophysics Data System (ADS)

Huang, Jie; Xu, Fanghua; Zhou, Kuanbo; Xiu, Peng; Lin, Yanluan

2017-08-01

Temporal evolution of near-surface chlorophyll (CHL) associated with mesoscale eddies over entire eddy lifespan is complicated. Based on satellite measurements and a reanalysis data set, we identify and quantify major temporal and spatial CHL responses in cyclonic eddies in the southeastern Pacific, and explore the associated mechanisms. Only few temporal CHL variations can be directly linked to the four primary mechanisms: "eddy pumping," "eddy trapping," "eddy stirring," and "eddy-induced Ekman pumping." About 80% of the temporal CHL variations are too complex to be explained by a single mechanism. Five characteristic CHL responses, including classic dipoles (CD), positive-dominant dipoles (PD), negative-dominant dipoles (ND), positive monopoles (PM), and negative monopoles (NM) are identified using the self-organizing map (SOM). CD, a dominant response induced primarily by "eddy stirring," has a continued increasing of frequency of occurrence with time, although its contribution to the total CHL variability remains low. As the secondary prominent response, NM has two peaks of frequency of occurrence at eddy formation and maturation stages, mainly accounted by "eddy trapping" after eddy breakup and "eddy-induced Ekman pumping," respectively. The sum of frequency of occurrence of PD and PM are comparable to that of NM. The initial positive CHL at eddy formation stage is associated with "eddy trapping." The significant positive CHL increase from the eddy intensification to early decay stage is mainly attributed to "eddy pumping." Although the frequency of occurrence of ND is the smallest, its contribution to negative CHL anomalies is unnegligible.

Object attributes combine additively in visual search

PubMed Central

Pramod, R. T.; Arun, S. P.

2016-01-01

We perceive objects as containing a variety of attributes: local features, relations between features, internal details, and global properties. But we know little about how they combine. Here, we report a remarkably simple additive rule that governs how these diverse object attributes combine in vision. The perceived dissimilarity between two objects was accurately explained as a sum of (a) spatially tuned local contour-matching processes modulated by part decomposition; (b) differences in internal details, such as texture; (c) differences in emergent attributes, such as symmetry; and (d) differences in global properties, such as orientation or overall configuration of parts. Our results elucidate an enduring question in object vision by showing that the whole object is not a sum of its parts but a sum of its many attributes. PMID:26967014

Which Basic Rules Underlie Social Judgments? Agency Follows a Zero-Sum Principle and Communion Follows a Non-Zero-Sum Principle.

PubMed

Dufner, Michael; Leising, Daniel; Gebauer, Jochen E

2016-05-01

How are people who generally see others positively evaluated themselves? We propose that the answer to this question crucially hinges on the content domain: We hypothesize that Agency follows a "zero-sum principle" and therefore people who see others ashighin Agency are perceived aslowin Agency themselves. In contrast, we hypothesize that Communion follows a "non-zero-sum principle" and therefore people who see others ashighin Communion are perceived ashighin Communion themselves. We tested these hypotheses in a round-robin and a half-block study. Perceiving others as agentic was indeed linked to being perceived as low in Agency. To the contrary, perceiving others as communal was linked to being perceived as high in Communion, but only when people directly interacted with each other. These results help to clarify the nature of Agency and Communion and offer explanations for divergent findings in the literature. © 2016 by the Society for Personality and Social Psychology, Inc.

Demonstration of Protection of a Superconducting Qubit from Energy Decay

NASA Astrophysics Data System (ADS)

Lin, Yen-Hsiang; Nguyen, Long B.; Grabon, Nicholas; San Miguel, Jonathan; Pankratova, Natalia; Manucharyan, Vladimir E.

2018-04-01

Long-lived transitions occur naturally in atomic systems due to the abundance of selection rules inhibiting spontaneous emission. By contrast, transitions of superconducting artificial atoms typically have large dipoles, and hence their lifetimes are determined by the dissipative environment of a macroscopic electrical circuit. We designed a multilevel fluxonium artificial atom such that the qubit's transition dipole can be exponentially suppressed by flux tuning, while it continues to dispersively interact with a cavity mode by virtual transitions to the noncomputational states. Remarkably, energy decay time T1 grew by 2 orders of magnitude, proportionally to the inverse square of the transition dipole, and exceeded the benchmark value of T1>2 ms (quality factor Q1>4 ×107) without showing signs of saturation. The dephasing time was limited by the first-order coupling to flux noise to about 4 μ s . Our circuit validated the general principle of hardware-level protection against bit-flip errors and can be upgraded to the 0 -π circuit [P. Brooks, A. Kitaev, and J. Preskill, Phys. Rev. A 87, 052306 (2013), 10.1103/PhysRevA.87.052306], adding protection against dephasing and certain gate errors.

49 CFR 1017.10 - Procedures for administrative offset.

Code of Federal Regulations, 2010 CFR

2010-10-01

... TRANSPORTATION BOARD, DEPARTMENT OF TRANSPORTATION GENERAL RULES AND REGULATIONS DEBT COLLECTION-COLLECTION BY OFFSET FROM INDEBTED GOVERNMENT AND FORMER GOVERNMENT EMPLOYEES § 1017.10 Procedures for administrative offset. (a) Debts will be collected in one lump sum where possible. If the employee is financially unable...

Accessing the nucleon transverse structure in inclusive deep inelastic scattering

DOE PAGES

Accardi, Alberto; Bacchetta, Alessandro

2017-09-06

Here, we revisit the standard analysis of inclusive Deep Inelastic Scattering off nucleons taking into account the fact that on-shell quarks cannot be present in the final state, but they rather decay into hadrons - a process that can be described in terms of suitable "jet" correlators. As a consequence, a spin-flip term associated with the invariant mass of the produced hadrons is generated non perturbatively and couples to the target's transversity distribution function. In inclusive cross sections, this provides an hitherto neglected and large contribution to the twist-3 part of the g 2 structure function, that can explain themore » discrepancy between recent calculations and fits of this quantity. It also provides an extension of the Burkhardt-Cottingham sum rule, putting constraints on the small-x behavior of the transversity function, as well as an extension of the Efremov-Teryaev-Leader sum rule, suggesting a novel way to measure the tensor charge of the proton.« less

Study of D →a0(980 )e+νe decay in the light-cone sum rules approach

NASA Astrophysics Data System (ADS)

Cheng, Xiao-Dong; Li, Hai-Bo; Wei, Bin; Xu, Yu-Guo; Yang, Mao-Zhi

2017-08-01

Within the QCD light-cone sum rule (LCSR) approach, we investigate the transition form factors of D →a0(980 ) up to the twist-3 light-cone distribution amplitudes (LCDAs) of the scalar meson a0(980 ) in the two-quark picture. Using these form factors, we calculate the differential decay widths and branching ratios of the D →a0(980 )e+νe semileptonic decays. We obtain B (D0→a0-(980 )e+νe)=(4.0 8-1.22+1.37)×10-4 and B (D+→a00(980 )e+νe)=(5.4 0-1.59+1.78)×10-4 . The results are sensitive to the a0(980 ) inner structure. These decays can be searched for at the BESIII experiment, and any experimental observations will be useful to identify internal quark contents of the a0(980 ) meson, which will shed light on understanding theoretical models.

Spectroscopic parameters and decays of the resonance Z_b(10610)

NASA Astrophysics Data System (ADS)

Agaev, S. S.; Azizi, K.; Sundu, H.

2017-12-01

The resonance Z_b(10610) is investigated as the diquark-antidiquark Z_b=[bu][\\overline{bd}] state with spin-parity JP=1+. The mass and current coupling of the resonance Z_b(10610) are evaluated using QCD two-point sum rule and taking into account the vacuum condensates up to ten dimensions. We study the vertices Z_bΥ (nS)π (n=1,2,3) by applying the QCD light-cone sum rule to compute the corresponding strong couplings g_{Z_bΥ (nS)π } and widths of the decays Z_b → Υ (nS)π . We explore also the vertices Z_b hb(mP)π (m=1,2) and calculate the couplings g_{Z_b hb(mP)π } and the widths of the decay channels Z_b → hb(mP)π . To this end, we calculate the mass and decay constants of the h_b(1P) and h_b(2P) mesons. The results obtained are compared with experimental data of the Belle Collaboration.

Finite-size effects in simulations of electrolyte solutions under periodic boundary conditions

NASA Astrophysics Data System (ADS)

Thompson, Jeffrey; Sanchez, Isaac

The equilibrium properties of charged systems with periodic boundary conditions may exhibit pronounced system-size dependence due to the long range of the Coulomb force. As shown by others, the leading-order finite-size correction to the Coulomb energy of a charged fluid confined to a periodic box of volume V may be derived from sum rules satisfied by the charge-charge correlations in the thermodynamic limit V -> ∞ . In classical systems, the relevant sum rule is the Stillinger-Lovett second-moment (or perfect screening) condition. This constraint implies that for large V, periodicity induces a negative bias of -kB T(2 V) - 1 in the total Coulomb energy density of a homogeneous classical charged fluid of given density and temperature. We present a careful study of the impact of such finite-size effects on the calculation of solute chemical potentials from explicit-solvent molecular simulations of aqueous electrolyte solutions. National Science Foundation Graduate Research Fellowship Program, Grant No. DGE-1610403.

In-medium properties of pseudoscalar D_s and B_s mesons

NASA Astrophysics Data System (ADS)

Chhabra, Rahul; Kumar, Arvind

2017-11-01

We calculate the shift in the masses and decay constants of D_s(1968) and B_s(5370) mesons in hot and dense asymmetric strange hadronic matter using QCD sum rules and chiral SU(3) model. In-medium strange quark condensates < \\bar{s}s> _{ρ _B}, and gluon condensates < α s/π {G^a}_{μ ν } {G^a}^{μ ν } > _{ρ _B}, to be used in the QCD sum rules for pseudoscalar D_s and B_s mesons, are calculated using a chiral SU(3) model. As an application of our present work, we calculate the in-medium decay widths of the excited (c\\bar{s}) states D_s^*(2715) and D_s^*(2860) decaying to (D_s(1968),η ) mesons. The medium effects in their decay widths are incorporated through the mass modification of the D_s(1968) and η mesons. The results of the present investigation may be helpful in understanding the possible outcomes of the future experiments like CBM and PANDA under the FAIR facility.

Finite-width Laplacian sum rules for 2++ tensor glueball in the instanton vacuum model

NASA Astrophysics Data System (ADS)

Chen, Junlong; Liu, Jueping

2017-01-01

The more carefully defined and more appropriate 2++ tensor glueball current is a S Uc(3 ) gauge-invariant, symmetric, traceless, and conserved Lorentz-irreducible tensor. After Lorentz decomposition, the invariant amplitude of the correlation function is abstracted and calculated based on the semiclassical expansion for quantum chromodynamics (QCD) in the instanton liquid background. In addition to taking the perturbative contribution into account, we calculate the contribution arising from the interaction (or the interference) between instantons and the quantum gluon fields, which is infrared free. Instead of the usual zero-width approximation for the resonances, the Breit-Wigner form with a correct threshold behavior for the spectral function of the finite-width three resonances is adopted. The properties of the 2++ tensor glueball are investigated via a family of the QCD Laplacian sum rules for the invariant amplitude. The values of the mass, decay width, and coupling constants for the 2++ resonance in which the glueball fraction is dominant are obtained.

Using Monte Carlo Simulations to Develop an Understanding of the Hyperpolarizability Near the Fundamental Limit

NASA Astrophysics Data System (ADS)

Shafei, Shoresh; Kuzyk, Mark C.; Kuzyk, Mark G.

2010-03-01

The hyperpolarizability governs all light-matter interactions. In recent years, quantum mechanical calculations have shown that there is a fundamental limit of the hyperpolarizability of all materials. The fundamental limits are calculated only under the assumption that the Thomas Kuhn sum rules and the three-level ansatz hold. (The three-level ansatz states that for optimized hyperpolarizability, only two excited states contribute to the hyperpolarizability.) All molecules ever characterized have hyperpolarizabilities that fall well below the limits. However, Monte Carlo simulations of the nonlinear polarizability have shown that attaining values close to the fundamental limit is theoretically possible; but, the calculations do not provide guidance with regards to what potentials are optimized. The focus of our work is to use Monte Carlo techniques to determine sets of energies and transition moments that are consistent with the sum rules, and study the constraints on their signs. This analysis will be used to implement a numerical proof of three-level ansatz.

An Empirical Model Building Criterion Based on Prediction with Applications in Parametric Cost Estimation.

DTIC Science & Technology

1980-08-01

varia- ble is denoted by 7, the total sum of squares of deviations from that mean is defined by n - SSTO - (-Y) (2.6) iul and the regression sum of...squares by SSR - SSTO - SSE (2.7) II 14 A selection criterion is a rule according to which a certain model out of the 2p possible models is labeled "best...dis- cussed next. 1. The R2 Criterion The coefficient of determination is defined by R2 . 1 - SSE/ SSTO . (2.8) It is clear that R is the proportion of

A time correlation function theory describing static field enhanced third order optical effects at interfaces.

PubMed

Neipert, Christine; Space, Brian

2006-12-14

Sum vibrational frequency spectroscopy, a second order optical process, is interface specific in the dipole approximation. At charged interfaces, there exists a static field, and as a direct consequence, the experimentally detected signal is a combination of enhanced second and static field induced third order contributions. There is significant evidence in the literature of the importance/relative magnitude of this third order contribution, but no previous molecularly detailed approach existed to separately calculate the second and third order contributions. Thus, for the first time, a molecularly detailed time correlation function theory is derived here that allows for the second and third order contributions to sum frequency vibrational spectra to be individually determined. Further, a practical, molecular dynamics based, implementation procedure for the derived correlation functions that describe the third order phenomenon is also presented. This approach includes a novel generalization of point atomic polarizability models to calculate the hyperpolarizability of a molecular system. The full system hyperpolarizability appears in the time correlation functions responsible for third order contributions in the presence of a static field.

A Novel Feature Level Fusion for Heart Rate Variability Classification Using Correntropy and Cauchy-Schwarz Divergence.

PubMed

Goshvarpour, Ateke; Goshvarpour, Atefeh

2018-04-30

Heart rate variability (HRV) analysis has become a widely used tool for monitoring pathological and psychological states in medical applications. In a typical classification problem, information fusion is a process whereby the effective combination of the data can achieve a more accurate system. The purpose of this article was to provide an accurate algorithm for classifying HRV signals in various psychological states. Therefore, a novel feature level fusion approach was proposed. First, using the theory of information, two similarity indicators of the signal were extracted, including correntropy and Cauchy-Schwarz divergence. Applying probabilistic neural network (PNN) and k-nearest neighbor (kNN), the performance of each index in the classification of meditators and non-meditators HRV signals was appraised. Then, three fusion rules, including division, product, and weighted sum rules were used to combine the information of both similarity measures. For the first time, we propose an algorithm to define the weights of each feature based on the statistical p-values. The performance of HRV classification using combined features was compared with the non-combined features. Totally, the accuracy of 100% was obtained for discriminating all states. The results showed the strong ability and proficiency of division and weighted sum rules in the improvement of the classifier accuracies.

Rapid sampling of stochastic displacements in Brownian dynamics simulations with stresslet constraints.

PubMed

Fiore, Andrew M; Swan, James W

2018-01-28

Brownian Dynamics simulations are an important tool for modeling the dynamics of soft matter. However, accurate and rapid computations of the hydrodynamic interactions between suspended, microscopic components in a soft material are a significant computational challenge. Here, we present a new method for Brownian dynamics simulations of suspended colloidal scale particles such as colloids, polymers, surfactants, and proteins subject to a particular and important class of hydrodynamic constraints. The total computational cost of the algorithm is practically linear with the number of particles modeled and can be further optimized when the characteristic mass fractal dimension of the suspended particles is known. Specifically, we consider the so-called "stresslet" constraint for which suspended particles resist local deformation. This acts to produce a symmetric force dipole in the fluid and imparts rigidity to the particles. The presented method is an extension of the recently reported positively split formulation for Ewald summation of the Rotne-Prager-Yamakawa mobility tensor to higher order terms in the hydrodynamic scattering series accounting for force dipoles [A. M. Fiore et al., J. Chem. Phys. 146(12), 124116 (2017)]. The hydrodynamic mobility tensor, which is proportional to the covariance of particle Brownian displacements, is constructed as an Ewald sum in a novel way which guarantees that the real-space and wave-space contributions to the sum are independently symmetric and positive-definite for all possible particle configurations. This property of the Ewald sum is leveraged to rapidly sample the Brownian displacements from a superposition of statistically independent processes with the wave-space and real-space contributions as respective covariances. The cost of computing the Brownian displacements in this way is comparable to the cost of computing the deterministic displacements. The addition of a stresslet constraint to the over-damped particle equations of motion leads to a stochastic differential algebraic equation (SDAE) of index 1, which is integrated forward in time using a mid-point integration scheme that implicitly produces stochastic displacements consistent with the fluctuation-dissipation theorem for the constrained system. Calculations for hard sphere dispersions are illustrated and used to explore the performance of the algorithm. An open source, high-performance implementation on graphics processing units capable of dynamic simulations of millions of particles and integrated with the software package HOOMD-blue is used for benchmarking and made freely available in the supplementary material.

Graphene-enhanced intermolecular interaction at interface between copper- and cobalt-phthalocyanines

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

Dou, Wei-Dong; Center of Super-Diamond and Advanced Films; Huang, Shu-Ping

2015-10-07

Interfacial electronic structures of copper-phthalocyanine (CuPc), cobalt-phthalocyanine (CoPc), and graphene were investigated experimentally by using photoelectron spectroscopy. While the CuPc/graphene interface shows flat band structure and negligible interfacial dipole indicating quite weak molecule-substrate interaction, the CuPc/CoPc/graphene interface shows a large interfacial dipole and obvious energy level bending. Controlled experiments ruled out possible influences from the change in film structure of CuPc and pure π–π interaction between CoPc and CuPc. Analysis based on X-ray photoelectron spectroscopy and density functional theory reveals that the decrease in the work function for the CuPc/CoPc/graphene system is induced by the intermolecular interaction between CuPc andmore » CoPc which is enhanced owning to the peculiar electronic properties at the CoPc-graphene interface.« less

Benchmarking Atomic Data for Astrophysics: Be-like Ions between B II and Ne VII

NASA Astrophysics Data System (ADS)

Wang, Kai; Chen, Zhan Bin; Zhang, Chun Yu; Si, Ran; Jönsson, Per; Hartman, Henrik; Gu, Ming Feng; Chen, Chong Yang; Yan, Jun

2018-02-01

Large-scale self-consistent multiconfiguration Dirac–Hartree–Fock and relativistic configuration interaction calculations are reported for the n≤slant 6 levels in Be-like ions from B II to Ne VII. Effects from electron correlation are taken into account by means of large expansions in terms of a basis of configuration state functions, and a complete and accurate data set of excitation energies; lifetimes; wavelengths; electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole line strengths; transition rates; and oscillator strengths for these levels is provided for each ion. Comparisons are made with available experimental and theoretical results. The uncertainty of excitation energies is assessed to be 0.01% on average, which makes it possible to find and rule out misidentifications and aid new line identifications involving high-lying levels in astrophysical spectra. The complete data set is also useful for modeling and diagnosing astrophysical plasmas.

Band lineup of lattice mismatched InSe/GaSe quantum well structures prepared by van der Waals epitaxy: Absence of interfacial dipoles

NASA Astrophysics Data System (ADS)

Lang, O.; Klein, A.; Pettenkofer, C.; Jaegermann, W.; Chevy, A.

1996-10-01

Epitaxial growth of the strongly lattice mismatched (6.5%) layered chalcogenides InSe and GaSe on each other is obtained with the concept of van der Waals epitaxy as proven by low-energy electron diffraction and scanning tunnel microscope. InSe/GaSe/InSe and GaSe/InSe/GaSe quantum well structures were prepared by molecular beam epitaxy and their interface properties were characterized by soft x-ray photoelectron spectroscopy. Valence and conduction band offsets are determined to be 0.1 and 0.9 eV, respectively, and do not depend on deposition sequence (commutativity). As determined from the measured work functions the interface dipole is 0.05 eV; the band lineup between the two materials is correctly predicted by the Anderson model (electron affinity rule).

Nuclear fluxes during coherent tunnelling in asymmetric double well potentials

NASA Astrophysics Data System (ADS)

Liu, ChunMei; Manz, Jörn; Yang, Yonggang

2015-08-01

Previous results for nuclear fluxes during coherent tunnelling of molecules with symmetric double well potentials are extended to fluxes in asymmetric double well potentials. The theory is derived using the two-state approximation (TSA). The symmetric system serves as a reference. As an example, we consider the one-dimensional model of the tunnelling inversion of oriented ammonia, with semiclassical dipole coupling to an electric field. The tunnelling splitting increases with the dipole coupling by a factor f≥slant 1. The tunnelling time decreases by 1/f. The nuclear density appears as the sum of two parts: The tunnelling part decreases as {1/f}2 times the density of the symmetric reference, whereas the non-tunnelling part is the initial density times ≤ft({{1-1}/f}2\\right). Likewise, the nuclear flux decreases by 1/f, with essentially the same shape as for the symmetric reference, with maximum value at the potential barrier. Coherent nuclear tunnellings starting from the upper or lower wells of the asymmetric potential are equivalent. The results are universal, in the frame of the TSA, hence they allow straightforward extrapolations from one system to others. This is demonstrated by the prediction of isotope effects for five isotopomers of ammonia.

Doubly resonant three-wave-mixing spectroscopy of a chiral coupled-chromophore system in solution: coherent two-dimensional optical activity spectroscopy.

PubMed

Cheon, Sangheon; Lee, Hochan; Choi, Jun-Ho; Cho, Minhaeng

2007-02-07

Theoretical descriptions of doubly resonant two-dimensional (2D) sum-frequency-generation (SFG) and difference-frequency-generation (DFG) spectroscopies of coupled-chromophore systems are presented. Despite that each electronic or vibrational chromophore is achiral, the interaction-induced chirality of a coupled multichromophore system in solution can be measured by using the doubly resonant 2D three-wave-mixing (3WM) spectroscopic method. An electronically coupled dimer, where each monomer is modeled as a simple two-level system, can have nonvanishing SFG (or DFG) properties, e.g., susceptibility in frequency domain or nonlinear response function in time domain, if the induced dipole vector of the dimer is not orthogonal to the vector product of the two monomer electronic transition dipole vectors. In order to demonstrate that these 2D 3WM spectroscopic methods can be used to determine the solution structure of a polypeptide, the authors carried out quantum chemistry calculations for an alanine dipeptide and obtained first- and second-order dipole derivatives associated with the amide I vibrational transitions of the dipeptide. It is shown that the numerically simulated 2D IR-IR SFG spectrum is highly sensitive to the dipeptide secondary structure and provides rich information on the one- and two-exciton states. It is believed that the theoretically proposed doubly resonant 2D 3WM spectroscopy, which can be considered to be an optical activity spectroscopy, will be of use in studying both structural and dynamical aspects of coupled multichromophore systems, such as proteins, nucleic acids, nanoparticle aggregates etc.

The Effect of Combined Magnetic Geometries on Thermally Driven Winds. II. Dipolar, Quadrupolar, and Octupolar Topologies

NASA Astrophysics Data System (ADS)

Finley, Adam J.; Matt, Sean P.

2018-02-01

During the lifetime of Sun-like or low-mass stars a significant amount of angular momentum is removed through magnetized stellar winds. This process is often assumed to be governed by the dipolar component of the magnetic field. However, observed magnetic fields can host strong quadrupolar and/or octupolar components, which may influence the resulting spin-down torque on the star. In Paper I, we used the MHD code PLUTO to compute steady-state solutions for stellar winds containing a mixture of dipole and quadrupole geometries. We showed the combined winds to be more complex than a simple sum of winds with these individual components. This work follows the same method as Paper I, including the octupole geometry, which not only increases the field complexity but also, more fundamentally, looks for the first time at combining the same symmetry family of fields, with the field polarity of the dipole and octupole geometries reversing over the equator (unlike the symmetric quadrupole). We show, as in Paper I, that the lowest-order component typically dominates the spin-down torque. Specifically, the dipole component is the most significant in governing the spin-down torque for mixed geometries and under most conditions for real stars. We present a general torque formulation that includes the effects of complex, mixed fields, which predicts the torque for all the simulations to within 20% precision, and the majority to within ≈5%. This can be used as an input for rotational evolution calculations in cases where the individual magnetic components are known.

Molecular and supramolecular control of the work function of an inorganic electrode with self-assembled monolayer of umbrella-shaped fullerene derivatives.

PubMed

Lacher, Sebastian; Matsuo, Yutaka; Nakamura, Eiichi

2011-10-26

The surface properties of inorganic substrates can be altered by coating with organic molecules, which may result in the improvement of the properties suitable for electronic or biological applications. This article reports a systematic experimental study on the influence of the molecular and supramolecular properties of umbrella-shaped penta(organo)[60]fullerene derivatives, and on the work function and the water contact angle of indium-tin oxide (ITO) and gold surfaces. We could relate these macroscopic characteristics to single-molecular level properties, such as ionization potential and molecular dipole. The results led us to conclude that the formation of a SAM of a polar compound generates an electronic field through intermolecular interaction of the molecular charges, and this field makes the overall dipole of the SAM much smaller than the one expected from the simple sum of the dipoles of all molecules in the SAM. This effect, which was called depolarization and previously discussed theoretically, is now quantitatively probed by experiments. The important physical properties in surface science such as work function, ionization potential, and water contact angles have been mutually correlated at the level of molecular structures and molecular orientations on the substrate surface. We also found that the SAMs on ITO and gold operate under the same principle except that the "push-back" effect operates specifically for gold. The study also illustrates the ability of the photoelectron yield spectroscopy technique to rapidly measure the work function of a SAM-covered substrate and the ionization potential value of a molecule on the surface.

25 CFR 163.22 - Payment for forest products.

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2010-04-01

...) Terms and conditions for payment of forest products under lump sum (predetermined volume) sales shall be... Forest Management and Operations § 163.22 Payment for forest products. (a) The basis of volume determination for forest products sold shall be the Scribner Decimal C log rules, cubic volume, lineal...

Correlational correction to plasmon dispersion

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

Kalman, G.; Golden, K.I.

The authors question the suggestion that plasmon dispersion increases for small values of the coupling over its random-phase-approximation value, and conclude that, contrary to what has been stated in the literature, it does not: high-frequency-moment sum-rule and Kramers-Kronig arguments, when properly treated, do not entail such a consequence.

40 CFR Appendix II to Subpart V of... - Arbitration Rules

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78 FR 66841 - Israel Loan Guarantees Issued Under the Emergency Wartime Supplemental Appropriations Act of 2003...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-07

... AGENCY FOR INTERNATIONAL DEVELOPMENT 22 CFR Part 230 Israel Loan Guarantees Issued Under the... International Development (USAID). ACTION: Final rule. SUMMARY: This regulation prescribes the revised... International Development, may issue loan guarantees applicable to sums borrowed by the Government of Israel on...

Developmental Trajectories and Antecedents of Distal Parental Supervision

ERIC Educational Resources Information Center

Laird, Robert D.; Criss, Michael M.; Pettit, Gregory S.; Bates, John E.; Dodge, Kenneth A.

2009-01-01

Groups of adolescents were identified on the basis of developmental trajectories of their families' rules and their parents' knowledge of their activities. Characteristics of the adolescent, peer antisociality, and family context were tested as antecedents. In sum, 404 parent-adolescent dyads provided data for adolescents aged 10-16. Most…

Toward complete pion nucleon amplitudes

DOE PAGES

Mathieu, Vincent; Danilkin, Igor V.; Fernández-Ramírez, Cesar; ...

2015-10-05

We compare the low-energy partial wave analyses πN scattering with a high-energy data via finite energy sum rules. We also construct a new set of amplitudes by matching the imaginary part from the low-energy analysis with the high-energy, Regge parametrization and then reconstruct the real parts using dispersion relations.

10 CFR 600.315 - Revision of budget and program plans.

Code of Federal Regulations, 2010 CFR

2010-01-01

....315 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS FINANCIAL ASSISTANCE RULES... Requirements § 600.315 Revision of budget and program plans. (a) The budget plan is the financial expression of the project or program as approved during the award process. It includes the sum of the Federal and...

Enigmatic photon absorption in plasmas near solar interior conditions

NASA Astrophysics Data System (ADS)

Iglesias, Carlos A.

2015-06-01

Large systematic discrepancies between theoretical and experimental photon absorption of Fe plasmas applicable to the solar interior were reported [Bailey et al., Nature 517, 56 (2015)]. The disagreement is examined in the context of the Thomas-Reiche-Kuhn f-sum rule. The analysis identifies several anomalies in the experimental results.

Atomic Spectra and the Vector Model

NASA Astrophysics Data System (ADS)

Candler, A. C.

2015-05-01

12. Displaced terms; 13. Combination of several electrons; 14. Short periods; 15. Long periods; 16. Rare earths; 17. Intensity relsations; 18. Sum rules and (jj) coupling; 19. Series limit; 20. Hyperfine structure; 21. Quadripole radiation; 22. Fluorescent crystals; Appendix 5. Key to references; Appendix 6. Bibliography; Subject index; Author index.

39 CFR 3060.22 - Financial status report.

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2010-07-01

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Inclusive inelastic scattering of heavy ions and nuclear correlations

NASA Technical Reports Server (NTRS)

Cucinotta, Francis A.; Townsend, Lawrence W.; Wilson, John W.; Khandelwal, Govind S.

1990-01-01

Calculations of inclusive inelastic scattering distributions for heavy ion collisions are considered within the high energy optical model. Using ground state sum rules, the inclusive projectile and complete projectile-target inelastic angular distributions are treated in both independent particle and correlated nuclear models. Comparisons between the models introduced are made for alpha particles colliding with He-4, C-12, and O-16 targets and protons colliding with O-16. Results indicate that correlations contribute significantly, at small momentum transfers, to the inelastic sum. Correlation effects are hidden, however, when total scattering distributions are considered because of the dominance of elastic scattering at small momentum transfers.

Neutron-hole strength in the N = 81 isotones

NASA Astrophysics Data System (ADS)

Howard, A. M.; Freeman, S. J.; Schiffer, J. P.; Bloxham, T.; Clark, J. A.; Deibel, C. M.; Kay, B. P.; Parker, P. D.; Sharp, D. K.; Thomas, J. S.

2012-09-01

The distribution of neutron-hole strength has been studied in the N = 81 isotones 137Ba, 139Ce, 141Nd and 143Sm through the single-neutron removing reactions (p,d) and (3He,α), at energies of 23 and 34 MeV, respectively. Systematic cross section measurements were made at angles sensitive to the transferred angular momentum, and spectroscopic factors extracted through a distorted-wave Born approximation analysis. Application of the MacFarlane-French sum rules indicate an anomalously low summed g7/2 spectroscopic factor, most likely due to extensive fragmentation of the single-particle strength. Single-particle energies, based upon the centroids of observed strength, are presented.

Comparative analysis of substance use in ballet, dance sport, and synchronized swimming: results of a longitudinal study.

PubMed

Zenic, Natasa; Peric, Mia; Zubcevic, Nada Grcic; Ostojic, Zdenko; Ostojic, Ljerka

2010-06-01

There have been few studies comparing substance use and misuse (SU&M) in different performing arts forms. Herein, we identified and compared SU&M in women studying an art (ballet, n = 21), a non-Olympic sport (dance sport, n = 25), and an Olympic sport (synchronized swimming, n = 23). The sample of variables comprised general, educational, and sport factors, as well as SU&M data, including consumption of opiates, cigarettes, alcohol, nutritional supplements, doping behaviors, and beliefs. Using the Kruskal-Wallis test, we found no significant differences between study groups in potential doping behaviors. Most of the examinees reported that they did not rely on physicians' and/or coaches' opinions regarding doping. Only sport dancers recognized their consumption of cannabis as a violation of anti-doping rules. Those more convinced that doping habits are present in their sport (or art) have a certain tendency toward doping usage. In conclusion, a strong anti-doping campaign within the studied arts is suggested, focusing on the health-related problems of SU&M.

Born’s rule as signature of a superclassical current algebra

NASA Astrophysics Data System (ADS)

Fussy, S.; Mesa Pascasio, J.; Schwabl, H.; Grössing, G.

2014-04-01

We present a new tool for calculating the interference patterns and particle trajectories of a double-, three- and N-slit system on the basis of an emergent sub-quantum theory developed by our group throughout the last years. The quantum itself is considered as an emergent system representing an off-equilibrium steady state oscillation maintained by a constant throughput of energy provided by a classical zero-point energy field. We introduce the concept of a “relational causality” which allows for evaluating structural interdependences of different systems levels, i.e. in our case of the relations between partial and total probability density currents, respectively. Combined with the application of 21st century classical physics like, e.g., modern nonequilibrium thermodynamics, we thus arrive at a “superclassical” theory. Within this framework, the proposed current algebra directly leads to a new formulation of the guiding equation which is equivalent to the original one of the de Broglie-Bohm theory. By proving the absence of third order interferences in three-path systems it is shown that Born’s rule is a natural consequence of our theory. Considering the series of one-, double-, or, generally, of N-slit systems, with the first appearance of an interference term in the double slit case, we can explain the violation of Sorkin’s first order sum rule, just as the validity of all higher order sum rules. Moreover, the Talbot patterns and Talbot distance for an arbitrary N-slit device can be reproduced exactly by our model without any quantum physics tool.

A simple signaling rule for variable life-adjusted display derived from an equivalent risk-adjusted CUSUM chart.

PubMed

Wittenberg, Philipp; Gan, Fah Fatt; Knoth, Sven

2018-04-17

The variable life-adjusted display (VLAD) is the first risk-adjusted graphical procedure proposed in the literature for monitoring the performance of a surgeon. It displays the cumulative sum of expected minus observed deaths. It has since become highly popular because the statistic plotted is easy to understand. But it is also easy to misinterpret a surgeon's performance by utilizing the VLAD, potentially leading to grave consequences. The problem of misinterpretation is essentially caused by the variance of the VLAD's statistic that increases with sample size. In order for the VLAD to be truly useful, a simple signaling rule is desperately needed. Various forms of signaling rules have been developed, but they are usually quite complicated. Without signaling rules, making inferences using the VLAD alone is difficult if not misleading. In this paper, we establish an equivalence between a VLAD with V-mask and a risk-adjusted cumulative sum (RA-CUSUM) chart based on the difference between the estimated probability of death and surgical outcome. Average run length analysis based on simulation shows that this particular RA-CUSUM chart has similar performance as compared to the established RA-CUSUM chart based on the log-likelihood ratio statistic obtained by testing the odds ratio of death. We provide a simple design procedure for determining the V-mask parameters based on a resampling approach. Resampling from a real data set ensures that these parameters can be estimated appropriately. Finally, we illustrate the monitoring of a real surgeon's performance using VLAD with V-mask. Copyright © 2018 John Wiley & Sons, Ltd.

26 CFR 1.45D-1 - New markets tax credit.

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2010-04-01

... close of the taxable year of the taxpayer conducting such trade or business, the sum of the aggregate... qualified active low-income community business (ii) Purchase of certain loans from CDEs (A) In general (B...) Example (3) Special rule for reserves (4) Qualified active low-income community business (i) In general (A...

QCD for Postgraduates (3/5)

ScienceCinema

Zanderighi, Giulia

2018-04-27

Modern QCD - Lecture 3 We will introduce processes with initial-state hadrons and discuss parton distributions, sum rules, as well as the need for a factorization scale once radiative corrections are taken into account. We will then discuss the DGLAP equation, the evolution of parton densities, as well as ways in which parton densities are extracted from data.

26 CFR 1.162-11 - Rentals.

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2011-04-01

... purchaser may take as a deduction in his return an aliquot part of such sum each year, based on the number... or making permanent improvements on property of which he is the lessee is a capital investment, and... renewal and the relationship between the parties. As a general rule, unless the lease has been renewed or...

Partial Row-Sums of Pascal's Triangle

ERIC Educational Resources Information Center

Ollerton, Richard L.

2007-01-01

Identities for many and varied combinations of binomial coefficients abound. Indeed, because of the wide range of interrelationships it is possible that a great deal of mathematical effort has been wasted in proving essentially equivalent formulae. As well as proving identities these methods can be used to rule out closed form solutions (at least…

26 CFR 1.597-3 - Other rules.

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2011-04-01

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26 CFR 1.597-3 - Other rules.

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2014-04-01

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26 CFR 1.597-3 - Other rules.

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2013-04-01

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26 CFR 1.597-3 - Other rules.

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2010-04-01

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26 CFR 1.411(a)-7 - Definitions and special rules.

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2010-04-01

... this section), life insurance benefits payable as a lump sum, incidental death benefits, current life... annuity does not exceed the annual benefit of a single life annuity. (2) Defined contribution plan. In the case of a defined contribution plan, the balance of the employee's account held under the plan. (b...

26 CFR 53.4943-7 - Special rules for readjustments involving grandfathered holdings.

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2010-04-01

... of voting stock in a business enterprise owned (directly or indirectly) by a private foundation by... exceeds the greatest percentage of voting stock in any business enterprise owned (directly or indirectly... foundation in the exchange. (ii) If the sum of the percentage of voting stock in a business enterprise owned...

Interpretation of the new Ω _c0 states via their mass and width

NASA Astrophysics Data System (ADS)

Agaev, S. S.; Azizi, K.; Sundu, H.

2017-06-01

The masses and pole residues of the ground and first radially excited Ω _c0 states with spin-parities JP=1/2+, 3/2+, as well as P-wave Ω _c0 with JP=1/2-, 3/2- are calculated by means of the two-point QCD sum rules. The strong decays of Ω _c0 baryons are also studied and the widths of these decay channels are computed. The relevant computations are performed in the context of the full QCD sum rules on the light cone. The results obtained for the masses and widths are confronted with recent experimental data of the LHCb Collaboration, which allow us to interpret Ω _c(3000)0, Ω _c(3050)0, and Ω _c(3119)0 as the excited css baryons with the quantum numbers (1P, 1/2-), (1P, 3/2-), and (2S, 3/2+), respectively. The (2S, 1/2+) state can be assigned either to the Ω _c(3066)0 state or the Ω _c(3090)0 excited baryon.

Treating Zc(3900 ) and Z (4430 ) as the ground state and first radially excited tetraquarks

NASA Astrophysics Data System (ADS)

Agaev, S. S.; Azizi, K.; Sundu, H.

2017-08-01

Exploration of the resonances Zc(3900 ) and Z (4430 ) are performed by assuming that they are the ground state and first radial excitation of the same tetraquark with JP=1+. The mass and current coupling of the Zc(3900 ) and Z (4430 ) states are calculated using the QCD two-point sum rule method by taking into account vacuum condensates up to eight dimensions. We investigate the vertices ZcMhMl and Z MhMl, with Mh and Ml being the heavy and light mesons and evaluate the strong couplings gZcMhMl and gZ MhMl using the QCD sum rule on the light cone. The extracted couplings allow us to find the partial width of the decays Zc(3900 )→J /ψ π , ψ'π , ηcρ and Z (4430 )→ψ'π , J /ψ π , ηc'ρ , ηcρ , which may help in comprehensive investigation of these resonances. We compare the width of the decays of Zc(3900 ) and Z (4430 ) resonances with available experimental data as well as existing theoretical predictions.

The Z {yields} cc-bar {yields} {gamma}{gamma}*, Z {yields} bb-bar {yields} {gamma}{gamma}* triangle diagrams and the Z {yields} {gamma}{psi}, Z {yields} {gamma}Y decays

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

Achasov, N. N., E-mail: achasov@math.nsc.ru

2011-03-15

The approach to the Z {yields} {gamma}{psi} and Z {yields} {gamma}Y decay study is presented in detail, based on the sum rules for the Z {yields} cc-bar {yields} {gamma}{gamma}* and Z {yields} bb-bar {yields} {gamma}{gamma}* amplitudes and their derivatives. The branching ratios of the Z {yields} {gamma}{psi} and Z {yields} {gamma}Y decays are calculated for different hypotheses on saturation of the sum rules. The lower bounds of {Sigma}{sub {psi}} BR(Z {yields} {gamma}{psi}) = 1.95 Multiplication-Sign 10{sup -7} and {Sigma}{sub {upsilon}} BR(Z {yields} {gamma}Y) = 7.23 Multiplication-Sign 10{sup -7} are found. Deviations from the lower bounds are discussed, including the possibilitymore » of BR(Z {yields} {gamma}J/{psi}(1S)) {approx} BR(Z {yields} {gamma}Y(1S)) {approx} 10{sup -6}, that could be probably measured in LHC. The angular distributions in the Z {yields} {gamma}{psi} and Z {yields} {gamma}Y decays are also calculated.« less

QCD sum-rules analysis of vector (1-) heavy quarkonium meson-hybrid mixing

NASA Astrophysics Data System (ADS)

Palameta, A.; Ho, J.; Harnett, D.; Steele, T. G.

2018-02-01

We use QCD Laplace sum rules to study meson-hybrid mixing in vector (1-) heavy quarkonium. We compute the QCD cross-correlator between a heavy meson current and a heavy hybrid current within the operator product expansion. In addition to leading-order perturbation theory, we include four- and six-dimensional gluon condensate contributions as well as a six-dimensional quark condensate contribution. We construct several single and multiresonance models that take known hadron masses as inputs. We investigate which resonances couple to both currents and so exhibit meson-hybrid mixing. Compared to single resonance models that include only the ground state, we find that models that also include excited states lead to significantly improved agreement between QCD and experiment. In the charmonium sector, we find that meson-hybrid mixing is consistent with a two-resonance model consisting of the J /ψ and a 4.3 GeV resonance. In the bottomonium sector, we find evidence for meson-hybrid mixing in the ϒ (1 S ) , ϒ (2 S ), ϒ (3 S ), and ϒ (4 S ).

Exclusive QCD processes, quark-hadron duality, and the transition to perturbative QCD

NASA Astrophysics Data System (ADS)

Corianò, Claudio; Li, Hsiang-nan; Savkli, Cetin

1998-07-01

Experiments at CEBAF will scan the intermediate-energy region of the QCD dynamics for the nucleon form factors and for Compton Scattering. These experiments will definitely clarify the role of resummed perturbation theory and of quark-hadron duality (QCD sum rules) in this regime. With this perspective in mind, we review the factorization theorem of perturbative QCD for exclusive processes at intermediate energy scales, which embodies the transverse degrees of freedom of a parton and the Sudakov resummation of the corresponding large logarithms. We concentrate on the pion and proton electromagnetic form factors and on pion Compton scattering. New ingredients, such as the evolution of the pion wave function and the complete two-loop expression of the Sudakov factor, are included. The sensitivity of our predictions to the infrared cutoff for the Sudakov evolution is discussed. We also elaborate on QCD sum rule methods for Compton Scattering, which provide an alternative description of this process. We show that, by comparing the local duality analysis to resummed perturbation theory, it is possible to describe the transition of exclusive processes to perturbative QCD.

Sum rules across the unpolarized Compton processes involving generalized polarizabilities and moments of nucleon structure functions

NASA Astrophysics Data System (ADS)

Lensky, Vadim; Hagelstein, Franziska; Pascalutsa, Vladimir; Vanderhaeghen, Marc

2018-04-01

We derive two new sum rules for the unpolarized doubly virtual Compton scattering process on a nucleon, which establish novel low-Q2 relations involving the nucleon's generalized polarizabilities and moments of the nucleon's unpolarized structure functions F1(x ,Q2) and F2(x ,Q2). These relations facilitate the determination of some structure constants which can only be accessed in off-forward doubly virtual Compton scattering, not experimentally accessible at present. We perform an empirical determination for the proton and compare our results with a next-to-leading-order chiral perturbation theory prediction. We also show how these relations may be useful for a model-independent determination of the low-Q2 subtraction function in the Compton amplitude, which enters the two-photon-exchange contribution to the Lamb shift of (muonic) hydrogen. An explicit calculation of the Δ (1232 )-resonance contribution to the muonic-hydrogen 2 P -2 S Lamb shift yields -1 ±1 μ eV , confirming the previously conjectured smallness of this effect.

The spin structure of the deuteron

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

Frois, B.

1994-12-01

The Spin Muon Collaboration (SMC) has measured for the first time the spin-dependent structure function g{sub 1}{sup d} of the deuteron in the deep inelastic scattering of polarized muons on polarized deuterons in the kinematic range Q{sup 2} > 1 GeV{sup 2}, 0.006 < x < 0.6. The first moment {Gamma}{sub 1}{sup d} = {integral}{sub 0}{sup 1}g{sub 1}{sup d}dx = 0.023 {+-} 0.020(stat.) {+-} 0.015(syst.) is smaller than the prediction of the Ellis-Jaffe sum rules. The author finds that the fraction of the nucleon spin carried by strange quarks {Delta}s is appreciable and negative. Using earlier measurements of g{sub 1}{supmore » p}, the group can infer the first moment of the spin-dependent neutron structure function g{sub 1}{sup n}. The combined analysis of all the available data on the spin-dependent structure functions of the nucleon shows an excellent agreement among the data sets. The author does not find significant deviations from the prediction of the Bjorken sum rule.« less

Precision calculation of threshold πd scattering, πN scattering lengths, and the GMO sum rule

NASA Astrophysics Data System (ADS)

Baru, V.; Hanhart, C.; Hoferichter, M.; Kubis, B.; Nogga, A.; Phillips, D. R.

2011-12-01

We use chiral perturbation theory (ChPT) to calculate the πd scattering length with an accuracy of a few percent, including isospin-violating corrections in both the two- and three-body sectors. In particular, we provide the technical details of a recent letter (Baru et al., 2011) [1], where we used data on pionic deuterium and pionic hydrogen atoms to extract the isoscalar and isovector pion-nucleon scattering lengths a and a. We study isospin-breaking contributions to the three-body part of a due to mass differences, isospin violation in the πN scattering lengths, and virtual photons. This last class of effects is ostensibly infrared enhanced due to the smallness of the deuteron binding energy. However, we show that the leading virtual-photon effects that might undergo such enhancement cancel, and hence the standard ChPT counting provides a reliable estimate of isospin violation in a due to virtual photons. Finally, we discuss the validity of the Goldberger-Miyazawa-Oehme sum rule in the presence of isospin violation, and use it to determine the charged-pion-nucleon coupling constant.

Determination of the ground state of an Au-supported FePc film based on the interpretation of Fe K - and L -edge x-ray magnetic circular dichroism measurements

NASA Astrophysics Data System (ADS)

Natoli, Calogero R.; Krüger, Peter; Bartolomé, Juan; Bartolomé, Fernando

2018-04-01

We determine the magnetic ground state of the FePc molecule on Au-supported thin films based on the observed values of orbital anisotropy and spectroscopic x-ray magnetic circular dichroism (XMCD) measurements at the Fe K and L edges. Starting from ab initio molecular orbital multiplet calculations for the isolated molecule, we diagonalize the spin-orbit interaction in the subspace spanned by the three lowest spin triplet states of 3A2 g and 3Eg symmetry in the presence of a saturating magnetic field at a polar angle θ with respect to the normal to the plane of the film, plus an external perturbation representing the effect of the molecules in the stack on the FePc molecule under consideration. We find that the orbital moment of the ground state strongly depends on the magnetic field direction in agreement with the sum rule analysis of the L23-edge XMCD data. We calculate integrals over the XMCD spectra at the Fe K and L23 edges as used in the sum rules and explicitly show that they agree with the expectation values of the orbital moment and effective spin moment of the ground state. On the basis of this analysis, we can rule out alternative candidates proposed in the literature.

Mode Matching for Optical Antennas

NASA Astrophysics Data System (ADS)

Feichtner, Thorsten; Christiansen, Silke; Hecht, Bert

2017-11-01

The emission rate of a point dipole can be strongly increased in the presence of a well-designed optical antenna. Yet, optical antenna design is largely based on radio-frequency rules, ignoring, e.g., Ohmic losses and non-negligible field penetration in metals at optical frequencies. Here, we combine reciprocity and Poynting's theorem to derive a set of optical-frequency antenna design rules for benchmarking and optimizing the performance of optical antennas driven by single quantum emitters. Based on these findings a novel plasmonic cavity antenna design is presented exhibiting a considerably improved performance compared to a reference two-wire antenna. Our work will be useful for the design of high-performance optical antennas and nanoresonators for diverse applications ranging from quantum optics to antenna-enhanced single-emitter spectroscopy and sensing.

Multiconfiguration Dirac-Hartree-Fock energy levels, oscillator strengths, transition probabilities, hyperfine constants and Landé g-factor of intermediate Rydberg series in neutral argon atom

NASA Astrophysics Data System (ADS)

Salah, Wa'el; Hassouneh, Ola

2017-04-01

We computed the energy levels, oscillator strengths f_{ij}, the radiative transition rates A_{ij}, the Landé g -factor, the magnetic dipole moment and the electric quadrupole hyperfine constants of the intermediate Rydberg series ns [k]J ( 4 ≤ n ≤ 6), nd [k]J (3 ≤ n ≤ 4), np [k]J (4 ≤ n ≤ 5) relative to the ground state 3p6 1S0 for neutral argon atom spectra. The values are obtained in the framework of the multiconfiguration Dirac-Hartree-Fock (MCDHF) approach. In this approach, Breit interaction, leading quantum electrodynamics (QED) effects and self-energy correction are taken into account. Moreover, these spectroscopic parameters have been calculated for many levels belonging to the configuration 3p54s, 3p55s, 3p56s, 3p53d, 3p54d, 3p54p, 3p55p as well as for transitions between levels 3p54s-3p54p, 3p54p-3p53d, 3p54p-3p55s, 3p55s-3p55p and 3p55p-3p56s. The large majority of the lines from the 4p-5s and 4p-3d, 5s-5p and 5p-6s transition arrays have been observed and the calculations are consistent with the J -file-sum rule. The obtained theoretical values are compared with previous experimental and theoretical data available in the literature. An overall satisfactory agreement is noticed allowing assessing the reliability of our data.

26 CFR 1.467-4 - Section 467 loan.

Code of Federal Regulations, 2010 CFR

2010-04-01

... present values of all amounts payable by the lessor as interest on prepaid fixed rent, equals the sum of the present values of the fixed rent that accrues in accordance with § 1.467-1(d)(2). The yield must... terms of the rental agreement for that period. (4) Determination of present values. The rules for...

26 CFR 31.3211-2 - Rates and computation of employee representative tax.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) Rates—(1)(i) Tier 1 tax. The Tier 1 employee representative tax rate equals the sum of the tax rates in... employer tax for hospital insurance. The Tier 1 employee representative tax rate is applied to compensation... Insurance Contributions Act. (ii) Example. The rule in paragraph (a)(1)(i) of this section is illustrated by...

Radiation of a nonrelativistic particle during its finite motion in a central field

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

Karnakov, B. M., E-mail: karnak@theor.mephi.ru; Korneev, Ph. A., E-mail: korneev@theor.mephi.ru; Popruzhenko, S. V.

The spectrum and expressions for the intensity of dipole radiation lines are obtained for a classical nonrelativistic charged particle that executes a finite aperiodic motion in an arbitrary central field along a non-closed trajectory. It is shown that, in this case of a conditionally periodic motion, the radiaton spectrum consists of two series of equally spaced lines. It is pointed out that, according to the correspondence principle, the rise of two such series in the classical theory corresponds to the well-known selection rule |{delta}l = 1 for the dipole radiation in a central field in quantum theory, where l ismore » the orbital angular momentum of the particle. The results obtained can be applied to the description of the radiation and the absorption of a classical collisionless electron plasma in nanoparticles irradiated by an intense laser field. As an example, the rate of collisionless absorption of electromagnetic wave energy in equilibrium isotropic nanoplasma is calculated.« less

The Lore of the Hair

NASA Astrophysics Data System (ADS)

Yunes, Nicolas; Yagi, Kent; Stein, Leo

2016-03-01

Stars can be hairy beasts, especially in theories that go beyond Einstein's. In the latter, a scalar field can be sourced and anchored to a neutron star, and if the later is in a binary system, the scalar field will emit dipole radiation. This radiation removes energy from the binary, forcing the orbit to adiabatically decay much more rapidly than due to the emission of gravitational waves as predicted in General Relativity. The detailed radio observation of binary pulsars has constrained the orbital decay of compact binaries stringently, so much so that theories that predict neutron stars with scalar hair are believed to be essentially ruled out. In this talk I will explain why this ``lore'' is actually incorrect, providing a counter-example in which scalar hair is sourced by neutron stars, yet dipole radiation is absent. I will then describe what binary systems need to be observed to constrain such theories with future astrophysical observations. I acknowledge support from NSF CAREER Grant PHY-1250636.

Z Boson Decay into Light and Darkness.

PubMed

Fabbrichesi, M; Gabrielli, E; Mele, B

2018-04-27

We study the Z→γγ[over ¯] process in which the Z boson decays into a photon γ and a massless dark photon γ[over ¯], when the latter couples to standard-model fermions via dipole moments. This is a simple yet nontrivial example of how the Landau-Yang theorem-ruling out the decay of a massive spin-1 particle into two photons-is evaded if the final particles can be distinguished. The striking signature of this process is a resonant monochromatic single photon in the Z-boson center of mass together with missing momentum. LEP experimental bounds allow a branching ratio up to about 10^{-6} for such a decay. In a simplified model of the dark sector, the dark-photon dipole moments arise from one-loop exchange of heavy dark fermions and scalar messengers. The corresponding prediction for the rare Z→γγ[over ¯] decay width can be explored with the large samples of Z bosons foreseen at future colliders.

Z Boson Decay into Light and Darkness

NASA Astrophysics Data System (ADS)

Fabbrichesi, M.; Gabrielli, E.; Mele, B.

2018-04-01

We study the Z →γ γ ¯ process in which the Z boson decays into a photon γ and a massless dark photon γ ¯, when the latter couples to standard-model fermions via dipole moments. This is a simple yet nontrivial example of how the Landau-Yang theorem—ruling out the decay of a massive spin-1 particle into two photons—is evaded if the final particles can be distinguished. The striking signature of this process is a resonant monochromatic single photon in the Z -boson center of mass together with missing momentum. LEP experimental bounds allow a branching ratio up to about 10-6 for such a decay. In a simplified model of the dark sector, the dark-photon dipole moments arise from one-loop exchange of heavy dark fermions and scalar messengers. The corresponding prediction for the rare Z →γ γ ¯ decay width can be explored with the large samples of Z bosons foreseen at future colliders.

Rapid sampling of stochastic displacements in Brownian dynamics simulations with stresslet constraints

NASA Astrophysics Data System (ADS)

Fiore, Andrew M.; Swan, James W.

2018-01-01

Brownian Dynamics simulations are an important tool for modeling the dynamics of soft matter. However, accurate and rapid computations of the hydrodynamic interactions between suspended, microscopic components in a soft material are a significant computational challenge. Here, we present a new method for Brownian dynamics simulations of suspended colloidal scale particles such as colloids, polymers, surfactants, and proteins subject to a particular and important class of hydrodynamic constraints. The total computational cost of the algorithm is practically linear with the number of particles modeled and can be further optimized when the characteristic mass fractal dimension of the suspended particles is known. Specifically, we consider the so-called "stresslet" constraint for which suspended particles resist local deformation. This acts to produce a symmetric force dipole in the fluid and imparts rigidity to the particles. The presented method is an extension of the recently reported positively split formulation for Ewald summation of the Rotne-Prager-Yamakawa mobility tensor to higher order terms in the hydrodynamic scattering series accounting for force dipoles [A. M. Fiore et al., J. Chem. Phys. 146(12), 124116 (2017)]. The hydrodynamic mobility tensor, which is proportional to the covariance of particle Brownian displacements, is constructed as an Ewald sum in a novel way which guarantees that the real-space and wave-space contributions to the sum are independently symmetric and positive-definite for all possible particle configurations. This property of the Ewald sum is leveraged to rapidly sample the Brownian displacements from a superposition of statistically independent processes with the wave-space and real-space contributions as respective covariances. The cost of computing the Brownian displacements in this way is comparable to the cost of computing the deterministic displacements. The addition of a stresslet constraint to the over-damped particle equations of motion leads to a stochastic differential algebraic equation (SDAE) of index 1, which is integrated forward in time using a mid-point integration scheme that implicitly produces stochastic displacements consistent with the fluctuation-dissipation theorem for the constrained system. Calculations for hard sphere dispersions are illustrated and used to explore the performance of the algorithm. An open source, high-performance implementation on graphics processing units capable of dynamic simulations of millions of particles and integrated with the software package HOOMD-blue is used for benchmarking and made freely available in the supplementary material (ftp://ftp.aip.org/epaps/journ_chem_phys/E-JCPSA6-148-012805)

Secondary relaxation dynamics in rigid glass-forming molecular liquids with related structures.

PubMed

Li, Xiangqian; Wang, Meng; Liu, Riping; Ngai, Kia L; Tian, Yongjun; Wang, Li-Min; Capaccioli, Simone

2015-09-14

The dielectric relaxation in three glass-forming molecular liquids, 1-methylindole (1MID), 5H-5-Methyl-6,7-dihydrocyclopentapyrazine (MDCP), and Quinaldine (QN) is studied focusing on the secondary relaxation and its relation to the structural α-relaxation. All three glass-formers are rigid and more or less planar molecules with related chemical structures but have dipoles of different strengths at different locations. A strong and fast secondary relaxation is detected in the dielectric spectra of 1MID, while no resolved β-relaxation is observed in MDCP and QN. If the observed secondary relaxation in 1MID is identified with the Johari-Goldstein (JG) β-relaxation, then apparently the relation between the α- and β-relaxation frequencies of 1MID is not in accord with the Coupling Model (CM). The possibility of the violation of the prediction in 1MID as due to either the formation of hydrogen-bond induced clusters or the involvement of intramolecular degree of freedom is ruled out. The violation is explained by the secondary relaxation originating from the in-plane rotation of the dipole located on the plane of the rigid molecule, contributing to dielectric loss at higher frequencies and more intense than the JG β-relaxation generated by the out-of-plane rotation. MDCP has smaller dipole moment located in the plane of the molecule; however, presence of the change of curvature of dielectric loss, ε″(f), at some frequency on the high-frequency flank of the α-relaxation reveals the JG β-relaxation in MDCP and which is in accord with the CM prediction. QN has as large an in-plane dipole moment as 1MID, and the absence of the resolved secondary relaxation is explained by the smaller coupling parameter than the latter in the framework of the CM.

Empirical electronic polarizabilities: deviations from the additivity rule. I. M2+SO4·nH2O, blödite Na2M2+(SO4)2·4H2O, and kieserite-related minerals with sterically strained structures

NASA Astrophysics Data System (ADS)

Gagné, Olivier; Hawthorne, Frank; Shannon, Robert D.; Fischer, Reinhard X.

2017-09-01

Empirical electronic polarizabilities allow the prediction of total mineral polarizabilities and mean refractive indices of the vast majority of minerals and synthetic oxides. However, deviations from the valence-sum rule at cations in some minerals are associated with large deviations of observed from calculated total polarizabilities. We have identified several groups of minerals and compounds where deviations from the valence-sum rule at cations lead to polarizability deviations of 2-5%: M(SO4)·nH2O, n = 1-6, blödite-group minerals [Na2M2+(SO4)2·4H2O], and the kieserite-related minerals: isokite, panasqueiraite and tilasite. In these minerals, the environment of the M ions contains both O and H2O: Mg[O4(H2O)2] in kieserite, szmikite, and szomolnokite; Mg[O2(H2O)4] in starkeyite, ilesite, and rozenite, and Mg[(H2O)6] in hexahydrite. In compounds where the ligands are only H2O, deviations from the valence-sum rule at the M(H2O)6 groups are not accompanied by significant polarizability deviations. This is the case for epsomite, MgSO4·7H2O; bieberite, CoSO4·7H2O; goslarite, ZnSO4·7H2O, six silicofluorides, MSiF6·6H2O; eighteen Tutton's salts, M2M'(SO4)2·6H2O, where M = K, Rb, Cs and M' = Mg, Mn, Fe, Co, Ni, Cu, and Zn; and eleven MM'(SO4)2·12H2O alums, where M = Na, K, Rb and Cs, and M' = Al, Cr, Ga and In. This is also the case for the sulfates alunogen, Al2(SO4)3·17H2O and halotrichite, FeAl2(SO4)4·22H2O; three hydrated nitrates; one phosphate; three antimonates and two hydrated perchlorates. A possible explanation for this different behavior is that the bond-valence model treats O and H separately, whereas polarizability calculations treat the polarizability of the entire H2O molecule.

Chiral separation and twin-beam photonics

NASA Astrophysics Data System (ADS)

Bradshaw, David S.; Andrews, David L.

2016-03-01

It is well-known that, in a homogeneous fluid medium, most optical means that afford discrimination between molecules of opposite handedness are intrinsically weak effects. The reason is simple: the wide variety of origins for differential response commonly feature real or virtual electronic transitions that break a parity condition. Despite being electric dipole allowed, they manifest the chirality of the material in which they occur by breaking a selection rule that would otherwise preclude the simultaneous involvement of magnetic dipole or electric quadrupole forms of coupling. Although the latter are typically weaker than electric dipole effects by several orders of magnitude, it is the involvement of these weak forms of interaction that are responsible for chiral sensitivity. There have been a number of attempts to cleverly exploit novel optical configurations to enhance the relative magnitude - and hence potentially the efficiency - of chiral discrimination. The prospect of success in any such venture is enticing, because of the huge impact that such an advance might be expected to have in the health, food and medical sectors. Some of these proposals have utilized mirror reflection, and others surface plasmon coupling, or optical binding methods. Several recent works in the literature have drawn attention to a further possibility: the deployment of optical beam interference as a means to achieve chiral separations of sizeable extent. In this paper the underlying theory is fully developed to identify the true scope and limitations of such an approach.

Probabilistic combination of static and dynamic gait features for verification

NASA Astrophysics Data System (ADS)

Bazin, Alex I.; Nixon, Mark S.

2005-03-01

This paper describes a novel probabilistic framework for biometric identification and data fusion. Based on intra and inter-class variation extracted from training data, posterior probabilities describing the similarity between two feature vectors may be directly calculated from the data using the logistic function and Bayes rule. Using a large publicly available database we show the two imbalanced gait modalities may be fused using this framework. All fusion methods tested provide an improvement over the best modality, with the weighted sum rule giving the best performance, hence showing that highly imbalanced classifiers may be fused in a probabilistic setting; improving not only the performance, but also generalized application capability.

78 FR 12705 - Atlantic Highly Migratory Species; North and South Atlantic 2013 Commercial Swordfish Quotas

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-25

... dead discards. We will adjust the quotas in the final rule based on updated data, including dead... quota, the sum of updated landings data (from late reports) and dead discard estimates would need to reach or exceed 475 mt dw. In 2011, dead discards were estimated to equal 101.5 mt dw and late reports...

Value loss of hardwood lumber during air-drying

Treesearch

Leland F. Hanks; Margaret K. Peirsol

1975-01-01

Dry lumber prices were applied to green and air-dried lumber that was measured with a dry board rule. Values were summed by species, lumber grade, and thickness class. Differences between green and air-dried lumber value have been termed value losses and are given in dollars and in percentages. The percentages have been separated into loss due to shrinkage and loss due...

Open-flavor charm and bottom s q q ¯ Q ¯ and q q q ¯ Q ¯ tetraquark states

NASA Astrophysics Data System (ADS)

Chen, Wei; Chen, Hua-Xing; Liu, Xiang; Steele, T. G.; Zhu, Shi-Lin

2017-06-01

We provide comprehensive investigations for the mass spectrum of exotic open-flavor charmed/bottom s q q ¯ c ¯ , q q q ¯ c ¯ , s q q ¯ b ¯ , q q q ¯ b ¯ tetraquark states with various spin-parity assignments JP=0+,1+,2+ and 0- , 1- in the framework of QCD sum rules. In the diquark configuration, we construct the diquark-antidiquark interpolating tetraquark currents using the color-antisymmetric scalar and axial-vector diquark fields. The stable mass sum rules are established in reasonable parameter working ranges, which are used to give reliable mass predictions for these tetraquark states. We obtain the mass spectra for the open-flavor charmed/bottom s q q ¯c ¯, q q q ¯c ¯, s q q ¯b ¯, q q q ¯b ¯ tetraquark states with various spin-parity quantum numbers. In addition, we suggest searching for exotic doubly-charged tetraquarks, such as [s d ][u ¯ c ¯ ]→Ds(*)-π- in future experiments at facilities such as BESIII, BelleII, PANDA, LHCb, and CMS, etc.

Exploring the resonances X (4140 ) and X (4274 ) through their decay channels

NASA Astrophysics Data System (ADS)

Agaev, S. S.; Azizi, K.; Sundu, H.

2017-06-01

Investigation of the resonances X (4140 ) and X (4274 ), which were recently confirmed by the LHCb Collaboration [1], is carried out by treating them as the color triplet and sextet [c s ][c ¯ s ¯ ] diquark-antidiquark states with the spin-parity JP=1+ , respectively. We calculate the masses and meson-current couplings of these tetraquarks in the context of the QCD two-point sum rule method by taking into account the quark, gluon, and mixed vacuum condensates up to eight dimensions. We also study the vertices X (4140 )J /ψ ϕ and X (4274 )J /ψ ϕ and evaluate corresponding strong couplings gX (4140 )J /ψ ϕ and gX (4274 )J /ψ ϕ by means of the QCD light-cone sum rule method and a technique of the soft-meson approximation. In turn, these couplings contain required information to determine the width of the X (4140 )→J /ψ ϕ and X (4274 )→J /ψ ϕ decay channels. We compare our results for the masses and decay widths of the X (4140 ) and X (4274 ) resonances with the LHCb data and alternative theoretical predictions.

In-medium pseudoscalar D/B mesons and charmonium decay width

NASA Astrophysics Data System (ADS)

Chhabra, Rahul; Kumar, Arvind

2017-05-01

Using QCD sum rules and the chiral SU(3) model, we investigate the effect of temperature, density, strangeness fraction and isospin asymmetric parameter on the shift in masses and decay constants of the pseudoscalar D and B meson in the hadronic medium, which consist of nucleons and hyperons. The in-medium properties of D and B mesons within the QCD sum rule approach depend upon the quark and gluon condensates. In the chiral SU(3) model, quark and gluon condensates are introduced through the explicit symmetry breaking term and the trace anomaly property of the QCD, respectively and are written in terms of the scalar fields σ, ζ, δ and χ. Hence, through medium modification of σ, ζ, δ and χ fields, we obtain the medium-modified masses and decay constants of D and B mesons. As an application, using {}3P0 model, we calculate the in-medium decay width of the higher charmonium states ψ(3686), ψ(3770) and χ(3556) to the D\\bar{D} pairs, considering the in-medium mass of D mesons. These results may be important to understand the possible outcomes of the high-energy physics experiments, e.g., CBM and PANDA at GSI, Germany.

Broad diphoton resonance at the TeV? Not alone

NASA Astrophysics Data System (ADS)

Roig, Pablo; Sanz-Cillero, Juan José

2016-11-01

The hint for a possible resonance in the diphoton channel with mass of 750 GeV disappeared in the data presented at ICHEP'16 by ATLAS and CMS. However, the diphoton final state remains as one of the golden channels for new physics discoveries at the TeV scale in the LHC experiments. This motivates us to analyze model independently the implications of an O (TeV ) bump in the γ γ final state. By means of forward sum rules for γ γ scattering, we show that a spin-zero resonance with mass of the order of the TeV and a sizable γ γ partial width—-of the order of a few GeV—must be accompanied by higher-spin resonances with JR≥2 with similar properties, as expected in strongly coupled extensions of the Standard Model or, alternatively, in higher-dimensional deconstructed duals. Furthermore, independently of whether the putative O (TeV ) candidate is a scalar or a tensor, the large contribution to the forward sum rules in the referred scenario implies the presence of states in the spectrum with JR≥2 , these high-spin particles being a manifestation of new extra dimensions or composite states of a new strong sector.

Powerful Voter Selection for Making Multistep Delegate Ballot Fair

NASA Astrophysics Data System (ADS)

Yamakawa, Hiroshi

For decision by majority, each voter often exercises his right by delegating to trustable other voters. Multi-step delegates rule allows indirect delegating through more than one voter, and this helps each voter finding his delegate voters. In this paper, we propose powerful voter selection method depending on the multi-step delegate rule. This method sequentially selects voters who is most delegated indirectly. Multi-agent simulation demonstrate that we can achieve highly fair poll results from small number of vote by using proposed method. Here, fairness is prediction accuracy to sum of all voters preferences for choices. In simulation, each voter selects choices arranged on one dimensional preference axis for voting. Acquaintance relationships among voters were generated as a random network, and each voter delegates some of his acquaintances who has similar preferences. We obtained simulation results from various acquaintance networks, and then averaged these results. Firstly, if each voter has enough acquaintances in average, proposed method can help predicting sum of all voters' preferences of choices from small number of vote. Secondly, if the number of each voter's acquaintances increases corresponding to an increase in the number of voters, prediction accuracy (fairness) from small number of vote can be kept in appropriate level.

Thermal behavior of Charmonium in the vector channel from QCD sum rules

NASA Astrophysics Data System (ADS)

Dominguez, C. A.; Loewe, M.; Rojas, J. C.; Zhang, Y.

2010-11-01

The thermal evolution of the hadronic parameters of charmonium in the vector channel, i.e. the J/Ψ resonance mass, coupling (leptonic decay constant), total width, and continuum threshold are analyzed in the framework of thermal Hilbert moment QCD sum rules. The continuum threshold s0 has the same behavior as in all other hadronic channels, i.e. it decreases with increasing temperature until the PQCD threshold s0 = 4mQ2 is reached at T≃1.22Tc (mQ is the charm quark mass). The other hadronic parameters behave in a very different way from those of light-light and heavy-light quark systems. The J/Ψ mass is essentially constant in a wide range of temperatures, while the total width grows with temperature up to T≃1.04Tc beyond which it decreases sharply with increasing T. The resonance coupling is also initially constant beginning to increase monotonically around T≃Tc. This behavior of the total width and of the leptonic decay constant is a strong indication that the J/Ψ resonance might survive beyond the critical temperature for deconfinement, in agreement with some recent lattice QCD results.

Mixed valent metals

NASA Astrophysics Data System (ADS)

Riseborough, P. S.; Lawrence, J. M.

2016-08-01

We review the theory of mixed-valent metals and make comparison with experiments. A single-impurity description of the mixed-valent state is discussed alongside the description of the nearly-integer valent or Kondo limit. The degeneracy N of the f-shell plays an important role in the description of the low-temperature Fermi-liquid state. In particular, for large N, there is a rapid cross-over between the mixed-valent and the Kondo limit when the number of f electrons is changed. We discuss the limitations on the application of the single-impurity description to concentrated compounds such as those caused by the saturation of the Kondo effect and those due to the presence of magnetic interactions between the impurities. This discussion is followed by a description of a periodic lattice of mixed-valent ions, including the role of the degeneracy N. The article concludes with a comparison of theory and experiment. Topics covered include the single-impurity Anderson model, Luttinger’s theorem, the Friedel sum rule, the Schrieffer-Wolff transformation, the single-impurity Kondo model, Kondo screening, the Wilson ratio, local Fermi-liquids, Fermi-liquid sum rules, the Noziéres exhaustion principle, Doniach’s diagram, the Anderson lattice model, the Slave-Boson method, etc.

Dimension-six matrix elements for meson mixing and lifetimes from sum rules

NASA Astrophysics Data System (ADS)

Kirk, M.; Lenz, A.; Rauh, T.

2017-12-01

The hadronic matrix elements of dimension-six Δ F = 0, 2 operators are crucial inputs for the theory predictions of mixing observables and lifetime ratios in the B and D system. We determine them using HQET sum rules for three-point correlators. The results of the required three-loop computation of the correlators and the one-loop computation of the QCD-HQET matching are given in analytic form. For mixing matrix elements we find very good agreement with recent lattice results and comparable theoretical uncertainties. For lifetime matrix elements we present the first ever determination in the D meson sector and the first determination of Δ B = 0 matrix elements with uncertainties under control — superseeding preliminary lattice studies stemming from 2001 and earlier. With our state-of-the-art determination of the bag parameters we predict: τ( B +)/ τ( B d 0 ) = 1.082 - 0.026 + 0.022 , τ( B s 0 )/ τ( B d 0 ) = 0.9994 ± 0.0025, τ( D +)/ τ( D 0) = 2. 7 - 0.8 + 0.7 and the mixing-observables in the B s and B d system, in good agreement with the most recent experimental averages.

Mixed valent metals

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

Riseborough, P. S.; Lawrence, Jon M.

Here, we review the theory of mixed-valent metals and make comparison with experiments. A single-impurity description of the mixed-valent state is discussed alongside the description of the nearly-integer valent or Kondo limit. The degeneracy N of the f-shell plays an important role in the description of the low-temperature Fermi-liquid state. In particular, for large N, there is a rapid cross-over between the mixed-valent and the Kondo limit when the number of f electrons is changed. We discuss the limitations on the application of the single-impurity description to concentrated compounds such as those caused by the saturation of the Kondo effectmore » and those due to the presence of magnetic interactions between the impurities. This discussion is followed by a description of a periodic lattice of mixed-valent ions, including the role of the degeneracy N. The article concludes with a comparison of theory and experiment. Topics covered include the single-impurity Anderson model, Luttinger's theorem, the Friedel sum rule, the Schrieffer–Wolff transformation, the single-impurity Kondo model, Kondo screening, the Wilson ratio, local Fermi-liquids, Fermi-liquid sum rules, the Nozieres exhaustion principle, Doniach's diagram, the Anderson lattice model, the Slave-Boson method, etc.« less

Mixed valent metals

DOE PAGES

Riseborough, P. S.; Lawrence, Jon M.

2016-07-04

Here, we review the theory of mixed-valent metals and make comparison with experiments. A single-impurity description of the mixed-valent state is discussed alongside the description of the nearly-integer valent or Kondo limit. The degeneracy N of the f-shell plays an important role in the description of the low-temperature Fermi-liquid state. In particular, for large N, there is a rapid cross-over between the mixed-valent and the Kondo limit when the number of f electrons is changed. We discuss the limitations on the application of the single-impurity description to concentrated compounds such as those caused by the saturation of the Kondo effectmore » and those due to the presence of magnetic interactions between the impurities. This discussion is followed by a description of a periodic lattice of mixed-valent ions, including the role of the degeneracy N. The article concludes with a comparison of theory and experiment. Topics covered include the single-impurity Anderson model, Luttinger's theorem, the Friedel sum rule, the Schrieffer–Wolff transformation, the single-impurity Kondo model, Kondo screening, the Wilson ratio, local Fermi-liquids, Fermi-liquid sum rules, the Nozieres exhaustion principle, Doniach's diagram, the Anderson lattice model, the Slave-Boson method, etc.« less

Quasiparticle Interactions in Neutron Matter for Applications in Neutron Stars

NASA Technical Reports Server (NTRS)

Wambach, J.; Anisworth, T. L.; Pines, D.

1993-01-01

A microscopic model for the quaisiparticle interaction in neutron matter is presented. Both particle-particle (pp) and particle-hole (ph) correlation are are included. The pp correlations are treated in semi-empirical way, while ph correlations are incorporated by solving coupled two-body equations for the particle hole interaction and the scattering amplitude on the Fermi sphere. The resulting integral equations self-consistently sum the ph reducible diagrams. Antisymmetry is kept at all stages and hence the forward-scattering sum rules are obeyed. Results for Landau parameters and transport coefficients in a density regime representing the crust of a neutron star are presented. We also estimate the S-1 gap parameter for neutron superfluidity and comment briefly on neutron-star implications.

Quasiparticle Interactions in Neutron Matter for Applications in Neutron Stars

NASA Technical Reports Server (NTRS)

Wambach, J; Ainsworth, T. L.; Pines, D.

1993-01-01

A microscopic model for the quasiparticle interaction in neutron matter is presented. Both-particle (pp) and particle-hole (ph) correlations are included. The pp correlations are treated in semi-empirical way, while ph correlations are incorporated by solving coupled two-body equations for particle-hole interaction and the scattering amplitude of the Fermi sphere. The resulting integral equations self-consistently sum the ph reducible diagrams. Antisymmetry is kept at all stages and hence the forward-scattering sum rules for the scattering amplitude are obeyed. Results for Landau parameters and transport coefficients in a density regime representing the crust of a neutron star are presented. We also estimate the (1)S(sub 0) gap parameter for neutron superfluidity and comment briefly on neutron-star implications.

Multiple scattering calculations of relativistic electron energy loss spectra

NASA Astrophysics Data System (ADS)

Jorissen, K.; Rehr, J. J.; Verbeeck, J.

2010-04-01

A generalization of the real-space Green’s-function approach is presented for ab initio calculations of relativistic electron energy loss spectra (EELS) which are particularly important in anisotropic materials. The approach incorporates relativistic effects in terms of the transition tensor within the dipole-selection rule. In particular, the method accounts for relativistic corrections to the magic angle in orientation resolved EELS experiments. The approach is validated by a study of the graphite CK edge, for which we present an accurate magic angle measurement consistent with the predicted value.

Photoionisation of molecular wavepackets - the NaK( C1Σ +) case

NASA Astrophysics Data System (ADS)

Andersson, Renée; Kadi, Malin; Davidsson, Jan; Hansson, Tony

2002-01-01

The ultrafast photoionisation dynamics of NaK molecules in the C(3) 1Σ + state is investigated by pump-probe spectroscopy. The results are consistent with decreasing electronic transition dipole moment for photoionisation of the C state with increasing internuclear separation, due to increasing Na +K - ion pair character of the C state at the outer turning point of the wavepacket trajectory. Effects of a possible low-lying superexcited state cannot be ruled out, though, and in general future studies on ultrafast photoionisation processes need to address in more detail such effects.

On the role of atomic metastability in the production of Balmer line radiation from ‘cold’ atomic hydrogen, deuterium and hydrogenic ion impurities in fusion edge plasmas

NASA Astrophysics Data System (ADS)

Hey, J. D.

2012-03-01

Published arguments, which assign an important role to atomic metastability in the production of ‘narrow’ Zeeman component radiation from the boundary region of fusion plasmas, are examined critically in relation to l-redistribution by proton and electron collisions, and mixing of unperturbed atomic states by the ion microfield and microfield gradient. It is concluded that these important processes indeed severely constrain the contribution from ‘metastable’ states to the generation of the hydrogen Balmer spectra, for electron concentrations above 1012 cm-3, as pointed out before by the present author (Hey et al 1999 J. Phys. B: At. Mol. Opt. Phys. 32 3555). The analysis of collision-induced l-redistribution represents an extension of that used previously (Hey et al 1996 Contrib. Plasma Phys. 36 583), applicable up to higher electron densities. For comparison purposes, we also consider the question of metastability of ionized helium in a low-temperature plasma, and that of some common hydrogenic impurities (C5+ and Ne9+) in a hydrogen (deuterium) fusion plasma. While for low nuclear charge Z the metastability of 2s1/2 levels is quenched by the plasma environment, it is much reduced in high-Z ions owing to the rapid increase with Z of the two-photon electric dipole (2E1) and magnetic dipole (M1) spontaneous transition rates to the ground state, whereas the role of the plasma in these cases is less important. The main new principle elaborated in this work is the sensitivity of atomic line strengths, and hence collision strengths, to perturbation by the plasma environment for transitions between fine-structure sublevels of the same principal quantum number. As the plasma microfield strength grows, ‘allowed’ transitions diminish in strength, while ‘forbidden’ transitions grow. However, owing to violation of the parity selection rule, there is an overall loss of collision strength available to transitions, resulting from the appearance of significant ‘self-strength’ contributions, in accord with the sum rules for the line strengths, which remain valid over the range of fields considered. Thus, the relative effectiveness per perturber of both electron and ion collisions, for inducing population transfer between fine-structure sublevels, diminishes as the sublevels evolve from a fine-structure dominated to a Stark-effect-dominated regime. In the concluding discussion, we mention that this finding may have a bearing on discrepancies claimed between Stark broadening theory developed by Griem (1967 Astrophys. J. 148 547) and by Watson (2006 J. Phys.B: At. Mol. Opt. Phys. 39 1889), and the measurements of Bell and co-workers (2000 Publ. Astron. Soc. Pac. 112 1236; 2011 Astrophys. Space Sci. 335 451) for high-n radio recombination lines from galactic H II regions. In the absence of detailed modelling to test this suggestion, however, it would be premature to attempt to draw any firm conclusions along these lines. This manuscript is dedicated to the memory of my esteemed colleague Dr. rer. nat. Manfred Korten (1940-2010).

Polarized excitons and optical activity in single-wall carbon nanotubes

NASA Astrophysics Data System (ADS)

Chang, Yao-Wen; Jin, Bih-Yaw

2018-05-01

The polarized excitons and optical activity of single-wall carbon nanotubes (SWNTs) are studied theoretically by π -electron Hamiltonian and helical-rotational symmetry. By taking advantage of the symmetrization, the single-particle energy and properties of a SWNT are characterized with the corresponding helical band structure. The dipole-moment matrix elements, magnetic-moment matrix elements, and the selection rules can also be derived. Based on different selection rules, the optical transitions can be assigned as the parallel-polarized, left-handed circularly-polarized, and right-handed circularly-polarized transitions, where the combination of the last two gives the cross-polarized transition. The absorption and circular dichroism (CD) spectra are simulated by exciton calculation. The calculated results are well comparable with the reported measurements. Built on the foundation, magnetic-field effects on the polarized excitons and optical activity of SWNTs are studied. Dark-bright exciton splitting and interband Faraday effect in the CD spectrum of SWNTs under an axial magnetic field are predicted. The Faraday rotation dispersion can be analyzed according to the selection rules of circular polarizations and the helical band structure.

Characterization of starch polymorphic structures using vibrational sum frequency generation spectroscopy.

PubMed

Kong, Lingyan; Lee, Christopher; Kim, Seong H; Ziegler, Gregory R

2014-02-20

The polymorphic structures of starch were characterized with vibrational sum frequency generation (SFG) spectroscopy. The noncentrosymmetry requirement of SFG spectroscopy allows for the detection of the ordered domains without spectral interferences from the amorphous phase and also the distinction of the symmetric elements among crystalline polymorphs. The V-type amylose was SFG-inactive due to the antiparallel packing of single helices in crystal unit cells, whereas the A- and B-type starches showed strong SFG peaks at 2904 cm(-1) and 2952-2968 cm(-1), which were assigned to CH stretching of the axial methine group in the ring and CH2 stretching of the exocyclic CH2OH side group, respectively. The CH2/CH intensity ratios of the A- and B-type starches are significantly different, indicating that the conformation of hydroxymethyl groups in these two polymorphs may be different. Cyclodextrin inclusion complexes were also analyzed as a comparison to the V-type amylose and showed that the head-to-tail and head-to-head stacking patterns of cyclodextrin molecules govern their SFG signals and peak positions. Although the molecular packing is different between V-type amylose and cyclodextrin inclusion complexes, both crystals show the annihilation of SFG signals when the functional group dipoles are arranged pointing in opposite directions.

Long-range interactions between polar bialkali ground-state molecules in arbitrary vibrational levels

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

Vexiau, R.; Lepers, M., E-mail: maxence.lepers@u-psud.fr; Aymar, M.

2015-06-07

We have calculated the isotropic C{sub 6} coefficients characterizing the long-range van der Waals interaction between two identical heteronuclear alkali-metal diatomic molecules in the same arbitrary vibrational level of their ground electronic state X{sup 1}Σ{sup +}. We consider the ten species made up of {sup 7}Li, {sup 23}Na, {sup 39}K, {sup 87}Rb, and {sup 133}Cs. Following our previous work [Lepers et al., Phys. Rev. A 88, 032709 (2013)], we use the sum-over-state formula inherent to the second-order perturbation theory, composed of the contributions from the transitions within the ground state levels, from the transition between ground-state and excited state levels,more » and from a crossed term. These calculations involve a combination of experimental and quantum-chemical data for potential energy curves and transition dipole moments. We also investigate the case where the two molecules are in different vibrational levels and we show that the Moelwyn-Hughes approximation is valid provided that it is applied for each of the three contributions to the sum-over-state formula. Our results are particularly relevant in the context of inelastic and reactive collisions between ultracold bialkali molecules in deeply bound or in Feshbach levels.« less

7 CFR 1710.2 - Definitions and rules of construction.

Code of Federal Regulations, 2010 CFR

2010-01-01

... as follows: EC16SE91.000 where: A=Distribution (plant), which equals Part E, Line 14(e) of RUS Form 7; B=General Plant, which equals Part E, Line 24(e) of RUS Form 7; C=Operating Revenue and Patronage Capital, which equals Part A, Line 1 of RUS Form 7; and D=Cost of Power, which equals the sum of Part A...

7 CFR 1710.2 - Definitions and rules of construction.

Code of Federal Regulations, 2014 CFR

2014-01-01

...=Distribution (plant), which equals Part E, Line 14(e) of RUS Form 7; B=General Plant, which equals Part E, Line 24(e) of RUS Form 7; C=Operating Revenue and Patronage Capital, which equals Part A, Line 1 of RUS Form 7; and D=Cost of Power, which equals the sum of Part A, Lines 2, 3, and 4 of RUS Form 7. Area...

7 CFR 1710.2 - Definitions and rules of construction.

Code of Federal Regulations, 2013 CFR

2013-01-01

... as follows: EC16SE91.000 where: A=Distribution (plant), which equals Part E, Line 14(e) of RUS Form 7; B=General Plant, which equals Part E, Line 24(e) of RUS Form 7; C=Operating Revenue and Patronage Capital, which equals Part A, Line 1 of RUS Form 7; and D=Cost of Power, which equals the sum of Part A...

7 CFR 1710.2 - Definitions and rules of construction.

Code of Federal Regulations, 2011 CFR

2011-01-01

... as follows: EC16SE91.000 where: A=Distribution (plant), which equals Part E, Line 14(e) of RUS Form 7; B=General Plant, which equals Part E, Line 24(e) of RUS Form 7; C=Operating Revenue and Patronage Capital, which equals Part A, Line 1 of RUS Form 7; and D=Cost of Power, which equals the sum of Part A...

7 CFR 1710.2 - Definitions and rules of construction.

Code of Federal Regulations, 2012 CFR

2012-01-01

... as follows: EC16SE91.000 where: A=Distribution (plant), which equals Part E, Line 14(e) of RUS Form 7; B=General Plant, which equals Part E, Line 24(e) of RUS Form 7; C=Operating Revenue and Patronage Capital, which equals Part A, Line 1 of RUS Form 7; and D=Cost of Power, which equals the sum of Part A...

Electroproduction of the N*(1535) resonance at large momentum transfer.

PubMed

Braun, V M; Göckeler, M; Horsley, R; Kaltenbrunner, T; Lenz, A; Nakamura, Y; Pleiter, D; Rakow, P E L; Rohrwild, J; Schäfer, A; Schierholz, G; Stüben, H; Warkentin, N; Zanotti, J M

2009-08-14

We report on the first lattice calculation of light-cone distribution amplitudes of the N*(1535) resonance, which are used to calculate the transition form factors at large momentum transfers using light-cone sum rules. In the region Q2>2 GeV2, where the light-cone expansion is expected to converge, the results appear to be in good agreement with the experimental data.

Towards a unifying theory for the first-, second-, and third-order molecular (non)linear optical response

NASA Astrophysics Data System (ADS)

Pérez-Moreno, Javier; Clays, Koen; Kuzyk, Mark G.

2010-05-01

We present a procedure for the modeling of the dispersion of the nonlinear optical response of complex molecular structures that is based strictly on the results from experimental characterization. We show how under some general conditions, the use of the Thomas-Kuhn sum-rules leads to a successful modeling of the nonlinear response of complex molecular structures.

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.

LipidMatch: an automated workflow for rule-based lipid identification using untargeted high-resolution tandem mass spectrometry data.

PubMed

Koelmel, Jeremy P; Kroeger, Nicholas M; Ulmer, Candice Z; Bowden, John A; Patterson, Rainey E; Cochran, Jason A; Beecher, Christopher W W; Garrett, Timothy J; Yost, Richard A

2017-07-10

Lipids are ubiquitous and serve numerous biological functions; thus lipids have been shown to have great potential as candidates for elucidating biomarkers and pathway perturbations associated with disease. Methods expanding coverage of the lipidome increase the likelihood of biomarker discovery and could lead to more comprehensive understanding of disease etiology. We introduce LipidMatch, an R-based tool for lipid identification for liquid chromatography tandem mass spectrometry workflows. LipidMatch currently has over 250,000 lipid species spanning 56 lipid types contained in in silico fragmentation libraries. Unique fragmentation libraries, compared to other open source software, include oxidized lipids, bile acids, sphingosines, and previously uncharacterized adducts, including ammoniated cardiolipins. LipidMatch uses rule-based identification. For each lipid type, the user can select which fragments must be observed for identification. Rule-based identification allows for correct annotation of lipids based on the fragments observed, unlike typical identification based solely on spectral similarity scores, where over-reporting structural details that are not conferred by fragmentation data is common. Another unique feature of LipidMatch is ranking lipid identifications for a given feature by the sum of fragment intensities. For each lipid candidate, the intensities of experimental fragments with exact mass matches to expected in silico fragments are summed. The lipid identifications with the greatest summed intensity using this ranking algorithm were comparable to other lipid identification software annotations, MS-DIAL and Greazy. For example, for features with identifications from all 3 software, 92% of LipidMatch identifications by fatty acyl constituents were corroborated by at least one other software in positive mode and 98% in negative ion mode. LipidMatch allows users to annotate lipids across a wide range of high resolution tandem mass spectrometry experiments, including imaging experiments, direct infusion experiments, and experiments employing liquid chromatography. LipidMatch leverages the most extensive in silico fragmentation libraries of freely available software. When integrated into a larger lipidomics workflow, LipidMatch may increase the probability of finding lipid-based biomarkers and determining etiology of disease by covering a greater portion of the lipidome and using annotation which does not over-report biologically relevant structural details of identified lipid molecules.

Dipole sources of the human alpha rhythm.

PubMed

Rodin, E A; Rodin, M J

1995-01-01

Dipole sources were investigated in 22 normal subjects with a variety of strategies available through the BESA program. When all the data were summed one regional source, located near the midline in the basal portions of the occipital lobe, explained 92% of the variance. Two regional sources, initially constrained for symmetry but subsequently freed from constraint placed them also in the occipital regions near the midline and reduced the residual variance to 4%. Pooled data obscure, however, the marked individual differences especially in regard to lateralization. In the individual case the major source was also always in one occipital area but its location, especially the degree of separation from the midline depended upon alpha distribution and the strategy used in the workup of the data. The orientation of the major components of the regional sources was usually in the posterior-anterior direction, fairly parallel to the midline and while the other one pointed to the upper convexity. Because of the considerable variability of the alpha rhythm in given subjects and even within the same individual a model which requires symmetry constraints is not optimal for all instances, even when constraints are lifted thereafter. The study demonstrated the feasibility of distinguishing predominantly mesial sources from those which are bihemipheric with more lateral origins but several different models may have to be used to reach the most realistic conclusions.

Photoabsorption cross section of acetylene in the EUV region

NASA Technical Reports Server (NTRS)

Wu, C. Y. R.; Judge, D. L.

1985-01-01

The measurement of the absolute photoabsorption cross sections of C2H2 in the 175-740 A region by means of a double ionization chamber is reported. The continuum background source is the synchrotron radiation emitted by the Wisconsin 240 MeV electron storage ring. It is found that the cross sections range from 2 to a maximum of 36 Mb. Two new Rydberg series are identified and the cross section data are applied in the analysis of various sum rules. From the rules, it is shown that the data of C2H2 in the 580-1088 A range may be too low, while the measured ionization transition moment may be too high.

Some rules for polydimensional squeezing

NASA Technical Reports Server (NTRS)

Manko, Vladimir I.

1994-01-01

The review of the following results is presented: For mixed state light of N-mode electromagnetic field described by Wigner function which has generic Gaussian form, the photon distribution function is obtained and expressed explicitly in terms of Hermite polynomials of 2N-variables. The momenta of this distribution are calculated and expressed as functions of matrix invariants of the dispersion matrix. The role of new uncertainty relation depending on photon state mixing parameter is elucidated. New sum rules for Hermite polynomials of several variables are found. The photon statistics of polymode even and odd coherent light and squeezed polymode Schroedinger cat light is given explicitly. Photon distribution for polymode squeezed number states expressed in terms of multivariable Hermite polynomials is discussed.

Application of ant colony Algorithm and particle swarm optimization in architectural design

NASA Astrophysics Data System (ADS)

Song, Ziyi; Wu, Yunfa; Song, Jianhua

2018-02-01

By studying the development of ant colony algorithm and particle swarm algorithm, this paper expounds the core idea of the algorithm, explores the combination of algorithm and architectural design, sums up the application rules of intelligent algorithm in architectural design, and combines the characteristics of the two algorithms, obtains the research route and realization way of intelligent algorithm in architecture design. To establish algorithm rules to assist architectural design. Taking intelligent algorithm as the beginning of architectural design research, the authors provide the theory foundation of ant colony Algorithm and particle swarm algorithm in architectural design, popularize the application range of intelligent algorithm in architectural design, and provide a new idea for the architects.

Process-independent strong running coupling

DOE PAGES

Binosi, Daniele; Mezrag, Cedric; Papavassiliou, Joannis; ...

2017-09-25

Here, we unify two widely different approaches to understanding the infrared behavior of quantum chromodynamics (QCD), one essentially phenomenological, based on data, and the other computational, realized via quantum field equations in the continuum theory. Using the latter, we explain and calculate a process-independent running-coupling for QCD, a new type of effective charge that is an analogue of the Gell-Mann–Low effective coupling in quantum electrodynamics. The result is almost identical to the process-dependent effective charge defined via the Bjorken sum rule, which provides one of the most basic constraints on our knowledge of nucleon spin structure. As a result, thismore » reveals the Bjorken sum to be a near direct means by which to gain empirical insight into QCD's Gell-Mann–Low effective charge.« less

Process-independent strong running coupling

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

Binosi, Daniele; Mezrag, Cedric; Papavassiliou, Joannis

Here, we unify two widely different approaches to understanding the infrared behavior of quantum chromodynamics (QCD), one essentially phenomenological, based on data, and the other computational, realized via quantum field equations in the continuum theory. Using the latter, we explain and calculate a process-independent running-coupling for QCD, a new type of effective charge that is an analogue of the Gell-Mann–Low effective coupling in quantum electrodynamics. The result is almost identical to the process-dependent effective charge defined via the Bjorken sum rule, which provides one of the most basic constraints on our knowledge of nucleon spin structure. As a result, thismore » reveals the Bjorken sum to be a near direct means by which to gain empirical insight into QCD's Gell-Mann–Low effective charge.« less

Angular momentum conservation law in light-front quantum field theory

DOE PAGES

Chiu, Kelly Yu-Ju; Brodsky, Stanley J.

2017-03-31

We prove the Lorentz invariance of the angular momentum conservation law and the helicity sum rule for relativistic composite systems in the light-front formulation. We explicitly show that j 3, the z -component of the angular momentum remains unchanged under Lorentz transformations generated by the light-front kinematical boost operators. The invariance of j 3 under Lorentz transformations is a feature unique to the front form. Applying the Lorentz invariance of the angular quantum number in the front form, we obtain a selection rule for the orbital angular momentum which can be used to eliminate certain interaction vertices in QED andmore » QCD. We also generalize the selection rule to any renormalizable theory and show that there exists an upper bound on the change of orbital angular momentum in scattering processes at any fixed order in perturbation theory.« less

Consultation sequencing of a hospital with multiple service points using genetic programming

NASA Astrophysics Data System (ADS)

Morikawa, Katsumi; Takahashi, Katsuhiko; Nagasawa, Keisuke

2018-07-01

A hospital with one consultation room operated by a physician and several examination rooms is investigated. Scheduled patients and walk-ins arrive at the hospital, each patient goes to the consultation room first, and some of them visit other service points before consulting the physician again. The objective function consists of the sum of three weighted average waiting times. The problem of sequencing patients for consultation is focused. To alleviate the stress of waiting, the consultation sequence is displayed. A dispatching rule is used to decide the sequence, and best rules are explored by genetic programming (GP). The simulation experiments indicate that the rules produced by GP can be reduced to simple permutations of queues, and the best permutation depends on the weight used in the objective function. This implies that a balanced allocation of waiting times can be achieved by ordering the priority among three queues.

Angular momentum conservation law in light-front quantum field theory

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

Chiu, Kelly Yu-Ju; Brodsky, Stanley J.

We prove the Lorentz invariance of the angular momentum conservation law and the helicity sum rule for relativistic composite systems in the light-front formulation. We explicitly show that j 3, the z -component of the angular momentum remains unchanged under Lorentz transformations generated by the light-front kinematical boost operators. The invariance of j 3 under Lorentz transformations is a feature unique to the front form. Applying the Lorentz invariance of the angular quantum number in the front form, we obtain a selection rule for the orbital angular momentum which can be used to eliminate certain interaction vertices in QED andmore » QCD. We also generalize the selection rule to any renormalizable theory and show that there exists an upper bound on the change of orbital angular momentum in scattering processes at any fixed order in perturbation theory.« less

Angular momentum conservation law in light-front quantum field theory

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

Chiu, Kelly Yu-Ju; Brodsky, Stanley J.

We prove the Lorentz invariance of the angular momentum conservation law and the helicity sum rule for relativistic composite systems in the light-front formulation. We explicitly show that j 3 , the z -component of the angular momentum remains unchanged under Lorentz transformations generated by the light-front kinematical boost operators. The invariance of j 3 under Lorentz transformations is a feature unique to the front form. Applying the Lorentz invariance of the angular quantum number in the front form, we obtain a selection rule for the orbital angular momentum which can be used to eliminate certain interaction vertices in QEDmore » and QCD. We also generalize the selection rule to any renormalizable theory and show that there exists an upper bound on the change of orbital angular momentum in scattering processes at any fixed order in perturbation theory.« less

Investigating the Role of Adducts in Protein Supercharging with Sulfolane

NASA Astrophysics Data System (ADS)

Douglass, Kevin Aart; Venter, Andre R.

2012-03-01

The supercharging effect of sulfolane on cytochrome c (cyt c) during electrospray ionization mass spectrometry (ESI-MS) in the absence of conformational effects was investigated. The addition of sulfolane on the order of 1 mM or greater to denaturing solutions of cyt c results in supercharging independent of protein concentration over the range of 0.1 to 10 μM. While supercharging was observed in the positive mode, no change in the charge state distribution was observed in the negative mode, ruling out polarity-independent factors such as conformational changes or surface tension effects. A series of sulfolane adducts observed with increasing intensity concurrent with increasing charge state suggests that a direct interaction between sulfolane and the charged sites of cyt c plays an important role in supercharging. We propose that charge delocalization occurring through large-scale dipole reordering of the highly polar supercharging reagent reduces the electrostatic barrier for proximal charging along the cyt c amino acid chain. Supporting this claim, supercharging was shown to increase with increasing dipole moment for several supercharging reagents structurally related to sulfolane.

Surface enhanced Raman optical activity of molecules on orientationally averaged substrates: theory of electromagnetic effects.

PubMed

Janesko, Benjamin G; Scuseria, Gustavo E

2006-09-28

We present a model for electromagnetic enhancements in surface enhanced Raman optical activity (SEROA) spectroscopy. The model extends previous treatments of SEROA to substrates, such as metal nanoparticles in solution, that are orientationally averaged with respect to the laboratory frame. Our theoretical treatment combines analytical expressions for unenhanced Raman optical activity with molecular polarizability tensors that are dressed by the substrate's electromagnetic enhancements. We evaluate enhancements from model substrates to determine preliminary scaling laws and selection rules for SEROA. We find that dipolar substrates enhance Raman optical activity (ROA) scattering less than Raman scattering. Evanescent gradient contributions to orientationally averaged ROA scale to first or higher orders in the gradient of the incident plane-wave field. These evanescent gradient contributions may be large for substrates with quadrupolar responses to the plane-wave field gradient. Some substrates may also show a ROA contribution that depends only on the molecular electric dipole-electric dipole polarizability. These conclusions are illustrated via numerical calculations of surface enhanced Raman and ROA spectra from (R)-(-)-bromochlorofluoromethane on various model substrates.

Distributed magnetic field positioning system using code division multiple access

NASA Technical Reports Server (NTRS)

Prigge, Eric A. (Inventor)

2003-01-01

An apparatus and methods for a magnetic field positioning system use a fundamentally different, and advantageous, signal structure and multiple access method, known as Code Division Multiple Access (CDMA). This signal architecture, when combined with processing methods, leads to advantages over the existing technologies, especially when applied to a system with a large number of magnetic field generators (beacons). Beacons at known positions generate coded magnetic fields, and a magnetic sensor measures a sum field and decomposes it into component fields to determine the sensor position and orientation. The apparatus and methods can have a large `building-sized` coverage area. The system allows for numerous beacons to be distributed throughout an area at a number of different locations. A method to estimate position and attitude, with no prior knowledge, uses dipole fields produced by these beacons in different locations.

The Balance-Scale Task Revisited: A Comparison of Statistical Models for Rule-Based and Information-Integration Theories of Proportional Reasoning

PubMed Central

Hofman, Abe D.; Visser, Ingmar; Jansen, Brenda R. J.; van der Maas, Han L. J.

2015-01-01

We propose and test three statistical models for the analysis of children’s responses to the balance scale task, a seminal task to study proportional reasoning. We use a latent class modelling approach to formulate a rule-based latent class model (RB LCM) following from a rule-based perspective on proportional reasoning and a new statistical model, the Weighted Sum Model, following from an information-integration approach. Moreover, a hybrid LCM using item covariates is proposed, combining aspects of both a rule-based and information-integration perspective. These models are applied to two different datasets, a standard paper-and-pencil test dataset (N = 779), and a dataset collected within an online learning environment that included direct feedback, time-pressure, and a reward system (N = 808). For the paper-and-pencil dataset the RB LCM resulted in the best fit, whereas for the online dataset the hybrid LCM provided the best fit. The standard paper-and-pencil dataset yielded more evidence for distinct solution rules than the online data set in which quantitative item characteristics are more prominent in determining responses. These results shed new light on the discussion on sequential rule-based and information-integration perspectives of cognitive development. PMID:26505905

Grammar and Learner as System: Some Proposed New Directions for Research in Second Language Acquisition. CUNYForum, No. 3.

ERIC Educational Resources Information Center

Pia, J. Joseph

Some aspects of a general systems theory of second language acquisition are as follows: the system is greater than the sum of its parts; each component has a distinctive role in the overall operation of the system; some components may be entire systems themselves; the workings of the system proceed according to patterns, and rules for any given…

26 CFR 1.663(a)-1 - Special rules applicable to sections 661 and 662; exclusions; gifts, bequests, etc.

Code of Federal Regulations, 2010 CFR

2010-04-01

...; exclusions; gifts, bequests, etc. (a) In general. A gift or bequest of a specific sum of money or of specific property, which is required by the specific terms of the will or trust instrument and is properly paid or... trust instrument the gift or bequest is to be paid or credited to the recipient in more than three...

Integral formulae of the canonical correlation functions for the one dimensional transverse Ising model

NASA Astrophysics Data System (ADS)

Inoue, Makoto

2017-12-01

Some new formulae of the canonical correlation functions for the one dimensional quantum transverse Ising model are found by the ST-transformation method using a Morita's sum rule and its extensions for the two dimensional classical Ising model. As a consequence we obtain a time-independent term of the dynamical correlation functions. Differences of quantum version and classical version of these formulae are also discussed.

Evolution equations for connected and disconnected sea parton distributions

NASA Astrophysics Data System (ADS)

Liu, Keh-Fei

2017-08-01

It has been revealed from the path-integral formulation of the hadronic tensor that there are connected sea and disconnected sea partons. The former is responsible for the Gottfried sum rule violation primarily and evolves the same way as the valence. Therefore, the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations can be extended to accommodate them separately. We discuss its consequences and implications vis-á-vis lattice calculations.

Mass formulas for {Xi}{sub c} and {Xi}{sub b} baryons

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

Aliev, T. M.; Zamiralov, V. S.; Ozpineci, A.

The importance of taking into account the mixing of the heavy cascade baryons {Xi} and {Xi}' that have new quantum numbers in analyzing their properties is shown. The Ono quark model is considered by way of example. The masses of the new baryons and the {Xi}-{Xi}' mixing angles are obtained. The same approach is applied to the interpolating currents of these baryons within QCD sum rules.

Electroproduction of the N*(1535) Resonance at Large Momentum Transfer

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

Braun, V. M.; Goeckeler, M.; Kaltenbrunner, T.

2009-08-14

We report on the first lattice calculation of light-cone distribution amplitudes of the N*(1535) resonance, which are used to calculate the transition form factors at large momentum transfers using light-cone sum rules. In the region Q{sup 2}>2 GeV{sup 2}, where the light-cone expansion is expected to converge, the results appear to be in good agreement with the experimental data.

Determinations of Vus using inclusive hadronic τ decay data

NASA Astrophysics Data System (ADS)

Maltman, Kim; Hudspith, Renwick James; Lewis, Randy; Izubuchi, Taku; Ohki, Hiroshi; Zanotti, James M.

2016-08-01

Two methods for determining |Vus| employing inclusive hadronic τ decay data are discussed. The first is the conventional flavor-breaking sum rule determination whose usual implementation produces results ˜ 3σ low compared to three-family unitary expectations. The second is a novel approach combining experimental strange hadronic τ distributions with lattice light-strange current-current two-point function data. Preliminary explorations of the latter show the method promises |Vus| determinations competitive with those from Kℓ3 and Γ[Kμ2]/Γ[πμ2]. For the former, systematic issues in the conventional implementation are investigated. Unphysical dependences of |Vus| on the choice of sum rule weight, w, and upper limit, s0, of the weighted experimental spectral integrals are observed, the source of these problems identified and a new implementation which overcomes these problems developed. Lattice results are shown to provide a tool for quantitatively assessing truncation uncertainties for the slowly converging D = 2 OPE series. The results for |Vus| from this new implementation are shown to be free of unphysical w- and s0-dependences, and ˜ 0.0020 higher than those produced by the conventional implementation. With preliminary new Kπ branching fraction results as input, we find |Vus| in excellent agreement with that obtained from Kℓ3, and compatible within errors with expectations from three-family unitarity.

Spectral assignment and orientational analysis in a vibrational sum frequency generation study of DPPC monolayers at the air/water interface

NASA Astrophysics Data System (ADS)

Feng, Rong-Juan; Li, Xia; Zhang, Zhen; Lu, Zhou; Guo, Yuan

2016-12-01

The interfacial behavior of the benchmark zwitterionic phospholipid molecule dipalmitoylphosphatidylcholine (DPPC) has been extensively investigated by surface-selective vibrational sum frequency generation spectroscopy (VSFG). However, there is still a lack of agreement between various orientational measurements of phospholipid monolayers at the air/water interface, mainly because of the difficulty in assigning congested VSFG features. In this study, polarization-dependent VSFG measurements reveal a frequency shift between the in-plane and out-of-plane antisymmetric stretching modes of the terminal methyl groups in the DPPC alkyl tails, favoring the model of Cs local symmetry rather than the previously assumed C3v symmetry. Further VSFG experiments of isotopically labeled DPPC successfully capture the vibrational signatures of the glycerol backbone. With the newly derived VSFG polarization selection rules for Cs symmetry and the refreshed spectral assignments, the average tilt angles of the alkyl tail groups, choline headgroup, and glycerol backbone of DPPC molecules can all be determined, showing the powerful capability of VSFG spectroscopy in revealing the structural details at interfaces. The VSFG polarization dependence rules and the orientational analysis procedures developed for Cs symmetry in this work are applicable to other bulky molecules in which the methyl group cannot freely rotate, and they therefore have general applications in future VSFG studies.

Sequential two-photon double ionization of noble gases by circularly polarized XUV radiation

NASA Astrophysics Data System (ADS)

Gryzlova, E. V.; Grum-Grzhimailo, A. N.; Kuzmina, E. I.; Strakhova, S. I.

2014-10-01

Photoelectron angular distributions (PADs) and angular correlations between two emitted electrons in sequential two-photon double ionization (2PDI) of atoms by circularly polarized radiation are studied theoretically. In particular, the sequential 2PDI of the valence n{{p}6} shell in noble gas atoms (neon, argon, krypton) is analyzed, accounting for the first-order corrections to the dipole approximation. Due to different selection rules in ionization transitions, the circular polarization of photons causes some new features of the cross sections, PADs and angular correlation functions in comparison with the case of linearly polarized photons.

Bayesian probability estimates are not necessary to make choices satisfying Bayes' rule in elementary situations.

PubMed

Domurat, Artur; Kowalczuk, Olga; Idzikowska, Katarzyna; Borzymowska, Zuzanna; Nowak-Przygodzka, Marta

2015-01-01

This paper has two aims. First, we investigate how often people make choices conforming to Bayes' rule when natural sampling is applied. Second, we show that using Bayes' rule is not necessary to make choices satisfying Bayes' rule. Simpler methods, even fallacious heuristics, might prescribe correct choices reasonably often under specific circumstances. We considered elementary situations with binary sets of hypotheses and data. We adopted an ecological approach and prepared two-stage computer tasks resembling natural sampling. Probabilistic relations were inferred from a set of pictures, followed by a choice which was made to maximize the chance of a preferred outcome. Use of Bayes' rule was deduced indirectly from choices. Study 1 used a stratified sample of N = 60 participants equally distributed with regard to gender and type of education (humanities vs. pure sciences). Choices satisfying Bayes' rule were dominant. To investigate ways of making choices more directly, we replicated Study 1, adding a task with a verbal report. In Study 2 (N = 76) choices conforming to Bayes' rule dominated again. However, the verbal reports revealed use of a new, non-inverse rule, which always renders correct choices, but is easier than Bayes' rule to apply. It does not require inversion of conditions [transforming P(H) and P(D|H) into P(H|D)] when computing chances. Study 3 examined the efficiency of three fallacious heuristics (pre-Bayesian, representativeness, and evidence-only) in producing choices concordant with Bayes' rule. Computer-simulated scenarios revealed that the heuristics produced correct choices reasonably often under specific base rates and likelihood ratios. Summing up we conclude that natural sampling results in most choices conforming to Bayes' rule. However, people tend to replace Bayes' rule with simpler methods, and even use of fallacious heuristics may be satisfactorily efficient.

Bayesian probability estimates are not necessary to make choices satisfying Bayes’ rule in elementary situations

PubMed Central

Domurat, Artur; Kowalczuk, Olga; Idzikowska, Katarzyna; Borzymowska, Zuzanna; Nowak-Przygodzka, Marta

2015-01-01

This paper has two aims. First, we investigate how often people make choices conforming to Bayes’ rule when natural sampling is applied. Second, we show that using Bayes’ rule is not necessary to make choices satisfying Bayes’ rule. Simpler methods, even fallacious heuristics, might prescribe correct choices reasonably often under specific circumstances. We considered elementary situations with binary sets of hypotheses and data. We adopted an ecological approach and prepared two-stage computer tasks resembling natural sampling. Probabilistic relations were inferred from a set of pictures, followed by a choice which was made to maximize the chance of a preferred outcome. Use of Bayes’ rule was deduced indirectly from choices. Study 1 used a stratified sample of N = 60 participants equally distributed with regard to gender and type of education (humanities vs. pure sciences). Choices satisfying Bayes’ rule were dominant. To investigate ways of making choices more directly, we replicated Study 1, adding a task with a verbal report. In Study 2 (N = 76) choices conforming to Bayes’ rule dominated again. However, the verbal reports revealed use of a new, non-inverse rule, which always renders correct choices, but is easier than Bayes’ rule to apply. It does not require inversion of conditions [transforming P(H) and P(D|H) into P(H|D)] when computing chances. Study 3 examined the efficiency of three fallacious heuristics (pre-Bayesian, representativeness, and evidence-only) in producing choices concordant with Bayes’ rule. Computer-simulated scenarios revealed that the heuristics produced correct choices reasonably often under specific base rates and likelihood ratios. Summing up we conclude that natural sampling results in most choices conforming to Bayes’ rule. However, people tend to replace Bayes’ rule with simpler methods, and even use of fallacious heuristics may be satisfactorily efficient. PMID:26347676

Molecular design for nonpolar chiral-axial quadratic nonlinear optics

NASA Astrophysics Data System (ADS)

Wiggers, Gregory A.

In this thesis the hyperpolarizability of various multi-dimensional molecules is studied theoretically/computationally, with particular focus on the second-rank Kleinman-disallowed (KD) component of the hyperpolarizability. This component, which transforms as a second-rank traceless symmetric tensor, could be utilized in certain chiral-axial molecular alignment schemes to produce a bulk response. Nonpolar chiral-axial systems have been proposed in contrast to polar media, which utilize the vector component of the molecular hyperpolarizability and require parallel alignment of the molecular dipoles. Such parallel alignment of dipoles must be "frozen in" in order to overcome the natural tendency for dipoles to align anti-parallel. This limits the density of chromophores that can be loaded into a polar material. Nonpolar materials do not have such limits in theory. The two geometric classes of molecules that can most easily be incorporated into nonpolar chiral-uniaxial materials are propeller-shaped (C3 or D3 symmetry) and Λ-shaped (C2v symmetry). This work describes efforts to design molecules within these classes that would be suitable for bulk NLO materials. The sum-over-states (SOS) expression is used to model the molecular hyperpolarizability, and quantum chemical calculations, along with linear absorption data (when available) provide the necessary parameters to evaluate truncated forms of the SOS expression. A host of chemical and geometric modifications will be considered in order to elucidate important structure/function relationships. Also, the SOS model will be tested in some cases when experimental measurements (via Kleinman-disallowed hyper-Rayleigh scattering) are available. While a majority of this work focuses on multi-dimensional molecules, a small section deals with the question of optimizing the hyperpolarizability of a one-dimensional system. It is suggested that the recently-proposed idea of "modulated conjugation" as a means for improving intrinsic molecular hyperpolarizability is based on subtle misinterpretations of computational results. Even so, the concept of modulated conjugation may lead to improved hyperpolarizabilities and possible reasons are discussed.

Deriving Laws from Ordering Relations

NASA Technical Reports Server (NTRS)

Knuth, Kevin H.

2004-01-01

The effect of Richard T. Cox's contribution to probability theory was to generalize Boolean implication among logical statements to degrees of implication, which are manipulated using rules derived from consistency with Boolean algebra. These rules are known as the sum rule, the product rule and Bayes Theorem, and the measure resulting from this generalization is probability. In this paper, I will describe how Cox s technique can be further generalized to include other algebras and hence other problems in science and mathematics. The result is a methodology that can be used to generalize an algebra to a calculus by relying on consistency with order theory to derive the laws of the calculus. My goals are to clear up the mysteries as to why the same basic structure found in probability theory appears in other contexts, to better understand the foundations of probability theory, and to extend these ideas to other areas by developing new mathematics and new physics. The relevance of this methodology will be demonstrated using examples from probability theory, number theory, geometry, information theory, and quantum mechanics.

Algebraic geometry and Bethe ansatz. Part I. The quotient ring for BAE

NASA Astrophysics Data System (ADS)

Jiang, Yunfeng; Zhang, Yang

2018-03-01

In this paper and upcoming ones, we initiate a systematic study of Bethe ansatz equations for integrable models by modern computational algebraic geometry. We show that algebraic geometry provides a natural mathematical language and powerful tools for understanding the structure of solution space of Bethe ansatz equations. In particular, we find novel efficient methods to count the number of solutions of Bethe ansatz equations based on Gröbner basis and quotient ring. We also develop analytical approach based on companion matrix to perform the sum of on-shell quantities over all physical solutions without solving Bethe ansatz equations explicitly. To demonstrate the power of our method, we revisit the completeness problem of Bethe ansatz of Heisenberg spin chain, and calculate the sum rules of OPE coefficients in planar N=4 super-Yang-Mills theory.

Reversal Frequency, Core-Mantle Conditions, and the SCOR-field Hypothesis

NASA Astrophysics Data System (ADS)

Hoffman, K. A.

2009-12-01

One of the most intriguing results from paleomagnetic data spanning the past 108 yr comes from the work of McFadden et al. (1991) who found that the variation in the rate of polarity reversal is apparently tied to the temporal variation in the harmonic content of the full-polarity field. Their finding indicates that it is the relative importance of the two dynamo families--i.e. the Primary Family (PF), the field antisymmetric about the equator, and the Secondary Family (SF), the field symmetric about the equator--that largely determines reversal frequency. More specifically, McFadden et al. found that as the relative significance of the SF increases, as is observed during the Cenozoic, so too does reversal rate. Such a finding is reminiscent of the seminal work of Allan Cox who some forty years ago proposed that interactions with the non-dipole field may provide the trigger for reversal of the axial dipole (AD) field. Hence, new questions arise: Do the two dynamo family fields interact in this manner, and, if so, how can such an interaction physically occur in the fluid core? Gaussian coefficient terms comprising the PF and SF have degree and order (n + m) that sum to an odd and even number, respectively. The most significant field term in the PF is by far that of the axial dipole (g10). The entire SF, starting with the equatorial dipole terms (g11 and h11) and the axial quadrupole (g20), are constituents of the non-axial dipole (NAD) field. By way of both paleomagnetic transition and geomagnetic data Hoffman and Singer (2008) recently proposed (1) that field sources exist within the shallow core (SCOR-field) associated with fluid motions affected by long-lived core-mantle boundary conditions; (2) that these SCOR-field sources are largely separated from, i.e. in “poor communication” with, deep field convection roll-generated sources; and (3) that the deep sources are largely responsible for the AD field, leaving the SCOR-field to be the primary source for the NAD-field. This SCOR-field would almost exclusively contain the observed SF field, while the AD-field sources deeper within the core would be most responsible for the observed PF field. If so, the McFadden et al. result may be explained as follows: That the observed increasing significance of the SF field during the Cenozoic is the result of intensifying interactions between shallow core SCOR-field sources and deep core AD-field sources. This then suggests a progressive enhancement in the variability of physical conditions along the CMB which may indicate an accelerating influx of descended lithospheric plates and/or increasing number of plume roots during the Cenozoic.

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

Brünner, F.; Parganlija, D.; Rebhan, A.

We present new results on the decay patterns of scalar and tensor glueballs in the top-down holographic Witten-Sakai-Sugimoto model. This model, which has only one free dimensionless parameter, gives semi-quantitative predictions for the vector meson spectrum, their decay widths, and also a gluon condensate in agreement with SVZ sum rules. The holographic predictions for scalar glueball decay rates are compared with experimental data for the widely discussed gluon candidates f{sub 0}(1500) and f{sub 0}(1710)

77 FR 21114 - Self-Regulatory Organizations; NYSE Arca, Inc.; Order Granting Approval of Proposed Rule Change...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-09

... Sugar 11. SB 03:30-14:00 2.25 ICE-US Cocoa CC 04:00-14:00 0.39 ICE-US Cotton 2. CT 21:00-14:30 1.24 CME... quotient of (i) the product of (a) the total annualized quantity traded of such Designated Contract during the relevant calculation period and (b) the sum of the products of (x) the Designated Contract...

Mixing {Xi}--{Xi}' Effects and Static Properties of Heavy {Xi}'s

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

Aliev, T. M.; Ozpineci, A.; Zamiralov, V. S.

It is shown the importance of mixing of heavy baryons {Xi}--{Xi}' with the new quantum numbers for analysis of its characteristics. The quark model of Ono is used as an example. Masses of new baryons as well as mixing angles of the states {Xi}--{Xi}' are obtained. The same reasoning is shown to be valid for the interpolating currents of these baryons in the framework of the QCD sum rules.

Direct Determinations of the πNN Coupling Constants

NASA Astrophysics Data System (ADS)

Ericson, T. E. O.; Loiseau, B.

1998-11-01

A novel extrapolation method has been used to deduce directly the charged πN N coupling constant from backward np differential scattering cross sections. The extracted value, g2c = 14.52(0.26) is higher than the indirectly deduced values obtained in nucleon-nucleon energy-dependent partial-wave analyses. Our preliminary direct value from a reanalysis of the GMO sum-rule points to an intermediate value of g2c about 13.97(30).

Scalar correlator at [symbol: see text](alpha(s)4), Higgs boson decay into bottom quarks, and bounds on the light-quark masses.

PubMed

Baikov, P A; Chetyrkin, K G; Kühn, J H

2006-01-13

We compute, for the first time, the absorptive part of the massless correlator of two quark scalar currents in five loops. As physical applications, we consider the [symbol: see text](alpha(s)4) corrections to the decay rate of the standard model Higgs boson into quarks, as well as the constraints on the strange quark mass following from QCD sum rules.

Multivariate Quality Control Procedures

DTIC Science & Technology

1988-10-01

CLASSIFICATION OF THIS PAGE PREFACE The mathematical modeling work described in this report was authorized under Project No. IC162706A553, CB Defense and...the sum of the measurements. A CUSUM of the first principal component would detect changes in the overall thickness of the sheet. A linear trend could...develop- ment of a unique outlier rule for the specific application. 28 LITERATURE CITED 1. Mood, A.M., Graybill , F.A., and Boes, D.C., Introduction to

A clinical prediction rule for detecting major depressive disorder in primary care: the PREDICT-NL study.

PubMed

Zuithoff, Nicolaas P A; Vergouwe, Yvonne; King, Michael; Nazareth, Irwin; Hak, Eelko; Moons, Karel G M; Geerlings, Mirjam I

2009-08-01

Major depressive disorder often remains unrecognized in primary care. Development of a clinical prediction rule using easily obtainable predictors for major depressive disorder in primary care patients. A total of 1046 subjects, aged 18-65 years, were included from seven large general practices in the center of The Netherlands. All subjects were recruited in the general practice waiting room, irrespective of their presenting complaint. Major depressive disorder according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Text Revision edition criteria was assessed with the Composite International Diagnostic Interview. Candidate predictors were gender, age, educational level, being single, number of presented complaints, presence of non-somatic complaints, whether a diagnosis was assigned, consultation rate in past 12 months, presentation of depressive complaints or prescription of antidepressants in past 12 months, number of life events in past 6 months and any history of depression. The first multivariable logistic regression model including only predictors that require no confronting depression-related questions had a reasonable degree of discrimination (area under the receiver operating characteristic curve or concordance-statistic (c-statistic) = 0.71; 95% Confidence Interval (CI): 0.67-0.76). Addition of three simple though more depression-related predictors, number of life events and history of depression, significantly increased the c-statistic to 0.80 (95% CI: 0.76-0.83). After transforming this second model to an easily to use risk score, the lowest risk category (sum score < 5) showed a 1% risk of depression, which increased to 49% in the highest category (sum score > or = 30). A clinical prediction rule allows GPs to identify patients-irrespective of their complaints-in whom diagnostic workup for major depressive disorder is indicated.

Structure and orientation of interfacial proteins determined by sum frequency generation vibrational spectroscopy: method and application.

PubMed

Ye, Shuji; Wei, Feng; Li, Hongchun; Tian, Kangzhen; Luo, Yi

2013-01-01

In situ and real-time characterization of molecular structures and orientation of proteins at interfaces is essential to understand the nature of interfacial protein interaction. Such work will undoubtedly provide important clues to control biointerface in a desired manner. Sum frequency generation vibrational spectroscopy (SFG-VS) has been demonstrated to be a powerful technique to study the interfacial structures and interactions at the molecular level. This paper first systematically introduced the methods for the calculation of the Raman polarizability tensor, infrared transition dipole moment, and SFG molecular hyperpolarizability tensor elements of proteins/peptides with the secondary structures of α-helix, 310-helix, antiparallel β-sheet, and parallel β-sheet, as well as the methodology to determine the orientation of interfacial protein secondary structures using SFG amide I spectra. After that, recent progresses on the determination of protein structure and orientation at different interfaces by SFG-VS were then reviewed, which provides a molecular-level understanding of the structures and interactions of interfacial proteins, specially understanding the nature of driving force behind such interactions. Although this review has focused on analysis of amide I spectra, it will be expected to offer a basic idea for the spectral analysis of amide III SFG signals and other complicated molecular systems such as RNA and DNA. Copyright © 2013 Elsevier Inc. All rights reserved.

Dependence of Sum Frequency Generation (SFG) Spectral Features on the Mesoscale Arrangement of SFG-Active Crystalline Domains Interspersed in SFG-Inactive Matrix: A Case Study with Cellulose in Uniaxially Aligned Control Samples and Alkali-Treated Secondary Cell Walls of Plants

DOE PAGES

Makarem, Mohamadamin; Sawada, Daisuke; O'Neill, Hugh M.; ...

2017-04-21

Vibrational sum frequency generation (SFG) spectroscopy can selectively detect not only molecules at two-dimensional (2D) interfaces but also noncentrosymmetric domains interspersed in amorphous three-dimensional (3D) matrixes. However, the SFG analysis of 3D systems is more complicated than 2D systems because more variables are involved. One such variable is the distance between SFG-active domains in SFG-inactive matrixes. In this study, we fabricated control samples in which SFG-active cellulose crystals were uniaxially aligned in an amorphous matrix. Assuming uniform separation distances between cellulose crystals, the relative intensities of alkyl (CH) and hydroxyl (OH) SFG peaks of cellulose could be related to themore » intercrystallite distance. The experimentally measured CH/OH intensity ratio as a function of the intercrystallite distance could be explained reasonably well with a model constructed using the theoretically calculated hyperpolarizabilities of cellulose and the symmetry cancellation principle of dipoles antiparallel to each other. In conclusion, this comparison revealed physical insights into the intercrystallite distance dependence of the CH/OH SFG intensity ratio of cellulose, which can be used to interpret the SFG spectral features of plant cell walls in terms of mesoscale packing of cellulose microfibrils.« less

A Paleointensity-Based Test of the Geocentric Axial Dipole (GAD) Hypothesis

NASA Astrophysics Data System (ADS)

Heimpel, M. H.; Veikkolainen, T.; Evans, M. E.; Pesonen, L. J.; Korhonen, K.

2016-12-01

The GAD model is central to many aspects of geophysics, including plate tectonics and paleoclimate. However, significant departures from a GAD field over geologic time have not been ruled out, particularly for the Precambrian. Here, we investigate a test of the GAD model using published paleointensity data. Our goals are to determine if paleointensities can shed light on the validity of the GAD model, and hence to see if they provide constraints on the evolution of the geodynamo throughout earth history. Using numerical dynamo models, we show that intensity distributions can be fairly well characterized by the first three zonal Gauss coefficients (dipole, quadrupole and octupole), although time-averaging tends to broaden the range of intensities. The dynamo models indicate that the ancient core, prior to nucleation of the inner core, may have had a significant (up to 10%) contribution of the zonal octupole. We then investigate the connection between the measured paleointensities assembled in the PINT database and the GAD model by means of predicted theoretical frequency distributions for various simple models (GAD, GAD ± small zonal quadrupole or octupole components). Hitherto, paleointensities have often been analysed in terms of corresponding virtual dipole moments (VDMs). But this rather begs the question because a GAD model is assumed in order to derive a VDM. By using raw field values reported from each sampling site we eliminate dependence on the GAD hypothesis. We find that models consisting of one or two different GADs cannot explain the data, but 3- or 4-GAD models can fit the data surprisingly well, and adding a ±5% octupole significantly improves the fit.

Aerodynamic and aeroacoustic for wind turbine

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

Mohamed, Maizi; Rabah, Dizene

2015-03-10

This paper describes a hybrid approach forpredicting noise radiated from the rotating Wind Turbine (HAWT) blades, where the sources are extracted from an unsteady Reynolds-Averaged-Navier Stocks (URANS) simulation, ANSYS CFX 11.0, was used to calculate The near-field flow parameters around the blade surface that are necessary for FW-H codes. Comparisons with NREL Phase II experimental results are presented with respect to the pressure distributions for validating a capacity of the solver to calculate the near-field flow on and around the wind turbine blades, The results show that numerical data have a good agreement with experimental. The acoustic pressure, presented asmore » a sum of thickness and loading noise components, is analyzed by means of a discrete fast Fourier transformation for the presentation of the time acoustic time histories in the frequency domain. The results convincingly show that dipole source noise is the dominant noise source for this wind turbine.« less

Stochastic Laplacian growth

NASA Astrophysics Data System (ADS)

Alekseev, Oleg; Mineev-Weinstein, Mark

2016-12-01

A point source on a plane constantly emits particles which rapidly diffuse and then stick to a growing cluster. The growth probability of a cluster is presented as a sum over all possible scenarios leading to the same final shape. The classical point for the action, defined as a minus logarithm of the growth probability, describes the most probable scenario and reproduces the Laplacian growth equation, which embraces numerous fundamental free boundary dynamics in nonequilibrium physics. For nonclassical scenarios we introduce virtual point sources, in which presence the action becomes the Kullback-Leibler entropy. Strikingly, this entropy is shown to be the sum of electrostatic energies of layers grown per elementary time unit. Hence the growth probability of the presented nonequilibrium process obeys the Gibbs-Boltzmann statistics, which, as a rule, is not applied out from equilibrium. Each layer's probability is expressed as a product of simple factors in an auxiliary complex plane after a properly chosen conformal map. The action at this plane is a sum of Robin functions, which solve the Liouville equation. At the end we establish connections of our theory with the τ function of the integrable Toda hierarchy and with the Liouville theory for noncritical quantum strings.

Pillars of judgment: how memory abilities affect performance in rule-based and exemplar-based judgments.

PubMed

Hoffmann, Janina A; von Helversen, Bettina; Rieskamp, Jörg

2014-12-01

Making accurate judgments is an essential skill in everyday life. Although how different memory abilities relate to categorization and judgment processes has been hotly debated, the question is far from resolved. We contribute to the solution by investigating how individual differences in memory abilities affect judgment performance in 2 tasks that induced rule-based or exemplar-based judgment strategies. In a study with 279 participants, we investigated how working memory and episodic memory affect judgment accuracy and strategy use. As predicted, participants switched strategies between tasks. Furthermore, structural equation modeling showed that the ability to solve rule-based tasks was predicted by working memory, whereas episodic memory predicted judgment accuracy in the exemplar-based task. Last, the probability of choosing an exemplar-based strategy was related to better episodic memory, but strategy selection was unrelated to working memory capacity. In sum, our results suggest that different memory abilities are essential for successfully adopting different judgment strategies. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Haunted by a doppelgänger: irrelevant facial similarity affects rule-based judgments.

PubMed

von Helversen, Bettina; Herzog, Stefan M; Rieskamp, Jörg

2014-01-01

Judging other people is a common and important task. Every day professionals make decisions that affect the lives of other people when they diagnose medical conditions, grant parole, or hire new employees. To prevent discrimination, professional standards require that decision makers render accurate and unbiased judgments solely based on relevant information. Facial similarity to previously encountered persons can be a potential source of bias. Psychological research suggests that people only rely on similarity-based judgment strategies if the provided information does not allow them to make accurate rule-based judgments. Our study shows, however, that facial similarity to previously encountered persons influences judgment even in situations in which relevant information is available for making accurate rule-based judgments and where similarity is irrelevant for the task and relying on similarity is detrimental. In two experiments in an employment context we show that applicants who looked similar to high-performing former employees were judged as more suitable than applicants who looked similar to low-performing former employees. This similarity effect was found despite the fact that the participants used the relevant résumé information about the applicants by following a rule-based judgment strategy. These findings suggest that similarity-based and rule-based processes simultaneously underlie human judgment.

On the analysis of photo-electron spectra

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

Gao, C.-Z., E-mail: gao@irsamc.ups-tlse.fr; CNRS, LPT; Dinh, P.M.

2015-09-15

We analyze Photo-Electron Spectra (PES) for a variety of excitation mechanisms from a simple mono-frequency laser pulse to involved combination of pulses as used, e.g., in attosecond experiments. In the case of simple pulses, the peaks in PES reflect the occupied single-particle levels in combination with the given laser frequency. This usual, simple rule may badly fail in the case of excitation pulses with mixed frequencies and if resonant modes of the system are significantly excited. We thus develop an extension of the usual rule to cover all possible excitation scenarios, including mixed frequencies in the attosecond regime. We find thatmore » the spectral distributions of dipole, monopole and quadrupole power for the given excitation taken together and properly shifted by the single-particle energies provide a pertinent picture of the PES in all situations. This leads to the derivation of a generalized relation allowing to understand photo-electron yields even in complex experimental setups.« less

Explanation of the barrier heights of graphene Schottky contacts by the MIGS-and-electronegativity concept

NASA Astrophysics Data System (ADS)

Mönch, Winfried

2016-09-01

Graphene-semiconductor contacts exhibit rectifying properties and, in this respect, they behave in exactly the same way as a "conventional" metal-semiconductor or Schottky contacts. It will be demonstrated that, as often assumed, the Schottky-Mott rule does not describe the reported barrier heights of graphene-semiconductor contacts. With "conventional" Schottky contacts, the same conclusion was reached already in 1940. The physical reason is that the Schottky-Mott rule considers no interaction between the metal and the semiconductor. The barrier heights of "conventional" Schottky contacts were explained by the continuum of metal-induced gap states (MIGSs), where the differences of the metal and semiconductor electronegativities describe the size and the sign of the intrinsic electric-dipoles at the interfaces. It is demonstrated that the MIGS-and-electronegativity concept unambiguously also explains the experimentally observed barrier heights of graphene Schottky contacts. This conclusion includes also the barrier heights reported for MoS2 Schottky contacts with "conventional" metals as well as with graphene.

Fine- and hyperfine-structure effects in molecular photoionization. I. General theory and direct photoionization.

PubMed

Germann, Matthias; Willitsch, Stefan

2016-07-28

We develop a model for predicting fine- and hyperfine intensities in the direct photoionization of molecules based on the separability of electron and nuclear spin states from vibrational-electronic states. Using spherical tensor algebra, we derive highly symmetrized forms of the squared photoionization dipole matrix elements from which we derive the salient selection and propensity rules for fine- and hyperfine resolved photoionizing transitions. Our theoretical results are validated by the analysis of the fine-structure resolved photoelectron spectrum of O2 reported by Palm and Merkt [Phys. Rev. Lett. 81, 1385 (1998)] and are used for predicting hyperfine populations of molecular ions produced by photoionization.

Design rules for quasi-linear nonlinear optical structures

NASA Astrophysics Data System (ADS)

Lytel, Richard; Mossman, Sean M.; Kuzyk, Mark G.

2015-09-01

The maximization of the intrinsic optical nonlinearities of quantum structures for ultrafast applications requires a spectrum scaling as the square of the energy eigenstate number or faster. This is a necessary condition for an intrinsic response approaching the fundamental limits. A second condition is a design generating eigenstates whose ground and lowest excited state probability densities are spatially separated to produce large differences in dipole moments while maintaining a reasonable spatial overlap to produce large off-diagonal transition moments. A structure whose design meets both conditions will necessarily have large first or second hyperpolarizabilities. These two conditions are fundamental heuristics for the design of any nonlinear optical structure.

Longitudinal magnet forces?

NASA Astrophysics Data System (ADS)

Graneau, P.

1984-03-01

The Ampere electrodynamics of metallic conductors and experiments supporting it predict that the interaction of a current-carrying wire with its own magnetic field should produce longitudinal mechanical forces in the conductor, existing in addition to the transverse Lorentz forces. The longitudinal forces should stretch the conductor and have been referred to as Ampere tension. In 1964 it was discovered that a current pulse would break a straight copper wire into many fragments without visible melting. A metallurgical examination of the pieces confirmed that the metal parted in the solid state. The same observation has now been made with aluminum wires. In the latest experiments the wire was bent into a semicircle and arc-connected to a capacitor discharge circuit. The arc connections ruled out rupture by Lorentz hoop tension and indicated the longitudinal forces may also arise in circular magnet windings. Explanations of wire fragmentation by thermal shock, longitudinal stress waves, Lorentz pinch-off, bending stresses, and material defects have been considered and found unconvincing. Computed Ampere tensions would be sufficient to fracture hot wires. The Ampere tension would double the hoop tension normally expected in dipole magnets. This should be borne in mind in the design of large dipole magnets contemplated for MHD power generators and railgun accelerators.

Can we estimate total magnetization directions from aeromagnetic data using Helbig's integrals?

USGS Publications Warehouse

Phillips, J.D.

2005-01-01

An algorithm that implements Helbig's (1963) integrals for estimating the vector components (mx, my, mz) of tile magnetic dipole moment from the first order moments of the vector magnetic field components (??X, ??Y, ??Z) is tested on real and synthetic data. After a grid of total field aeromagnetic data is converted to vector component grids using Fourier filtering, Helbig's infinite integrals are evaluated as finite integrals in small moving windows using a quadrature algorithm based on the 2-D trapezoidal rule. Prior to integration, best-fit planar surfaces must be removed from the component data within the data windows in order to make the results independent of the coordinate system origin. Two different approaches are described for interpreting the results of the integration. In the "direct" method, results from pairs of different window sizes are compared to identify grid nodes where the angular difference between solutions is small. These solutions provide valid estimates of total magnetization directions for compact sources such as spheres or dipoles, but not for horizontally elongated or 2-D sources. In the "indirect" method, which is more forgiving of source geometry, results of the quadrature analysis are scanned for solutions that are parallel to a specified total magnetization direction.

Band-edge engineering of Silicon by Surface Functionalization: a Combined Ab-initio and Photoemission Study

NASA Astrophysics Data System (ADS)

Li, Yan; O'Leary, Leslie; Lewis, Nathan; Galli, Giulia

2012-02-01

The electrode material choice is limited in solar to fuel formation devices because of the requirement of band-edge matching to the fixed fuel formation potential. This limitation can be relieved via band-edge engineering. The changes of band-edge positions of Si electrodes induced by the adsorption of H-, Cl-, Br- and short-chain alkyl groups were investigated by combining density functional (DFT), many-body perturbation theory (MBPT), and ultraviolet photoelectron spectroscopy. The band edge shifts are related to the formation of surface dipole moments, and determine the barrier height of electrons and holes in doped silicon surfaces. We find that the trends of the sign and magnitude of the computed surface dipoles as a function of the adsorbate may be explained by simple electronegative rules. We show that quasi-particle energies obtained within MBPT are in good agreement with experiment, while DFT values may exhibit substantial errors. However computed band edge differences are in good agreement with spectroscopic and electrical measurements even at the DFT level of theory. [1] Y. Li and G. Galli, Phys. Rev. B 82, 045321 (2010). [2] Y. Li, L. O'Leary, N. Lewis and G. Galli, to be submitted.

Suggested search for doubly charmed baryons of JP=3 /2+ via their electromagnetic transitions

NASA Astrophysics Data System (ADS)

Cui, Er-Liang; Chen, Hua-Xing; Chen, Wei; Liu, Xiang; Zhu, Shi-Lin

2018-02-01

We use the method of light-cone sum rules to study the electromagnetic transition of the Ξcc *++ into Ξcc ++γ , whose decay width is estimated to be 13.7-7.9+17.7 keV . This value is large enough for the Ξcc *++ to be observed in the Ξcc ++γ channel, and we propose to continually search for it in future LHCb and BelleII experiments.

Proton spin structure from measurable parton distributions.

PubMed

Ji, Xiangdong; Xiong, Xiaonu; Yuan, Feng

2012-10-12

We present a systematic study of the proton spin structure in terms of measurable parton distributions. For a transversely polarized proton, we derive a polarization sum rule from the leading generalized parton distributions appearing in hard exclusive processes. For a longitudinally polarized proton, we obtain a helicity decomposition from well-known quark and gluon helicity distributions and orbital angular-momentum contributions. The latter are shown to be related to measurable subleading generalized parton distributions and quantum-phase space Wigner distributions.

The Impact of Highly and Minimally Guided Discovery Instruction on Promoting the Learning of Reasoning Strategies for Basic Add-1 and Doubles Combinations

ERIC Educational Resources Information Center

Baroody, Arthur J.; Purpura, David J.; Eiland, Michael D.; Reid, Erin E.

2015-01-01

A 9-month training experiment was conducted to evaluate the efficacy of highly and minimally guided discovery interventions targeting the add-1 rule (the sum of a number and one is the next number on the mental number list) and doubles relations (e.g., an everyday example of the double 5 + 5 is five fingers on the left hand and five fingers on the…

Nickel L-edge and K-edge X-ray absorption spectroscopy of non-innocent Ni[S₂C₂(CF₃)₂]₂(n) series (n = -2, -1, 0): direct probe of nickel fractional oxidation state changes.

PubMed

Gu, Weiwei; Wang, Hongxin; Wang, Kun

2014-05-07

A series of nickel dithiolene complexes Ni[S2C2(CF3)2]2(n) (n = -2, -1, 0) has been investigated using Ni L- and K-edge X-ray absorption spectroscopy (XAS). The L3 centroid shifts about 0.3 eV for a change of one unit in the formal oxidation state (or 0.3 eV per oxi), corresponding to ~33% of the shift for Ni oxides or fluorides (about 0.9 eV per oxi). The K-edge XAS edge position shifts about 0.7 eV per oxi, corresponding to ~38% of that for Ni oxides (1.85 eV per oxi). In addition, Ni L sum rule analysis found the Ni(3d) ionicity in the frontier orbitals being 50.5%, 44.0% and 38.5% respectively (for n = -2, -1, 0), in comparison with their formal oxidation states (of Ni(II), Ni(III), and Ni(IV)). For the first time, direct and quantitative measurement of the Ni fractional oxidation state changes becomes possible for Ni dithiolene complexes, illustrating the power of L-edge XAS and L sum rule analysis in such a study. The Ni L-edge and K-edge XAS can be used in a complementary manner to better assess the oxidation states for Ni.

Local-duality QCD sum rules for strong isospin breaking in the decay constants of heavy-light mesons.

PubMed

Lucha, Wolfgang; Melikhov, Dmitri; Simula, Silvano

2018-01-01

We discuss the leptonic decay constants of heavy-light mesons by means of Borel QCD sum rules in the local-duality (LD) limit of infinitely large Borel mass parameter. In this limit, for an appropriate choice of the invariant structures in the QCD correlation functions, all vacuum-condensate contributions vanish and all nonperturbative effects are contained in only one quantity, the effective threshold. We study properties of the LD effective thresholds in the limits of large heavy-quark mass [Formula: see text] and small light-quark mass [Formula: see text]. In the heavy-quark limit, we clarify the role played by the radiative corrections in the effective threshold for reproducing the pQCD expansion of the decay constants of pseudoscalar and vector mesons. We show that the dependence of the meson decay constants on [Formula: see text] arises predominantly (at the level of 70-80%) from the calculable [Formula: see text]-dependence of the perturbative spectral densities. Making use of the lattice QCD results for the decay constants of nonstrange and strange pseudoscalar and vector heavy mesons, we obtain solid predictions for the decay constants of heavy-light mesons as functions of [Formula: see text] in the range from a few to 100 MeV and evaluate the corresponding strong isospin-breaking effects: [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text].

Moldauer's sum rule as a test of the consistency of transmission coefficients in Hauser Feshbach theory

NASA Astrophysics Data System (ADS)

Brown, David; Nobre, Gustavo; Herman, Michal

2017-09-01

For neutron induced reactions below 20 MeV incident energy, the Unresolved Resonance Region (URR) connects the fast neutron region with the Resolved Resonance Region (RRR). The URR is problematic since resonances are not resolvable experimentally yet the fluctuations in the neutron cross sections play a discernible and technologically important role - the URR in a typical nucleus is in the 100 keV - 2 MeV window where the typical fission spectrum peaks. The URR also represents the transition between R-matrix theory used to describe isolated resonances and Hauser-Feshbach theory which accurately describes the average cross sections. In practice, only average or systematic features of the resonances in the URR are known and are tabulated in evaluations in a nuclear data library such as ENDF/B-VII.1. Here we apply Moldauer's ``sum rule for resonance reactions'' to compute the effective transmission coefficients for reactions in the RRR and URR regions. We compare these to the transmission coefficients used in the fast region in the EMPIRE Hauser-Feshbach code, demonstrating the consistency (or lack thereof) between these different physical regimes. This work suggests a better approach to evaluating the URR average parameters using the results from the fast region modeling. This material is based upon work supported by the US Department of Energy, Office of Science, Office of Nuclear Physics, under Contract No. DE-SC0012704 (BNL).

Model-Free Adaptive Control for Unknown Nonlinear Zero-Sum Differential Game.

PubMed

Zhong, Xiangnan; He, Haibo; Wang, Ding; Ni, Zhen

2018-05-01

In this paper, we present a new model-free globalized dual heuristic dynamic programming (GDHP) approach for the discrete-time nonlinear zero-sum game problems. First, the online learning algorithm is proposed based on the GDHP method to solve the Hamilton-Jacobi-Isaacs equation associated with optimal regulation control problem. By setting backward one step of the definition of performance index, the requirement of system dynamics, or an identifier is relaxed in the proposed method. Then, three neural networks are established to approximate the optimal saddle point feedback control law, the disturbance law, and the performance index, respectively. The explicit updating rules for these three neural networks are provided based on the data generated during the online learning along the system trajectories. The stability analysis in terms of the neural network approximation errors is discussed based on the Lyapunov approach. Finally, two simulation examples are provided to show the effectiveness of the proposed method.

Review of the Theoretical Description of Time-Resolved Angle-Resolved Photoemission Spectroscopy in Electron-Phonon Mediated Superconductors

DOE PAGES

Kemper, A. F.; Sentef, M. A.; Moritz, B.; ...

2017-07-13

Here. we review recent work on the theory for pump/probe photoemission spectroscopy of electron-phonon mediated superconductors in both the normal and the superconducting states. We describe the formal developments that allow one to solve the Migdal-Eliashberg theory in nonequilibrium for an ultrashort laser pumping field, and explore the solutions which illustrate the relaxation as energy is transferred from electrons to phonons. We also focus on exact results emanating from sum rules and approximate numerical results which describe rules of thumb for relaxation processes. Additionally, in the superconducting state, we describe how Anderson-Higgs oscillations can be excited due to the nonlinearmore » coupling with the electric field and describe mechanisms where pumping the system enhances superconductivity.« less

Review of the Theoretical Description of Time-Resolved Angle-Resolved Photoemission Spectroscopy in Electron-Phonon Mediated Superconductors

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

Kemper, A. F.; Sentef, M. A.; Moritz, B.

Here. we review recent work on the theory for pump/probe photoemission spectroscopy of electron-phonon mediated superconductors in both the normal and the superconducting states. We describe the formal developments that allow one to solve the Migdal-Eliashberg theory in nonequilibrium for an ultrashort laser pumping field, and explore the solutions which illustrate the relaxation as energy is transferred from electrons to phonons. We also focus on exact results emanating from sum rules and approximate numerical results which describe rules of thumb for relaxation processes. Additionally, in the superconducting state, we describe how Anderson-Higgs oscillations can be excited due to the nonlinearmore » coupling with the electric field and describe mechanisms where pumping the system enhances superconductivity.« less

Various Ambiguities in Re-constructing Laser Pulse Parameters

NASA Technical Reports Server (NTRS)

Roychoudhuri, Chandrasekhar; Prasa, Narasimha

2006-01-01

We think that mode lock laser pulses are generated by the summation process that take place between the monochromatic EM filed frequencies as if they interact with each other as shown in equation 1. In reality, the pulse generation is a collaborative interaction process between EM fields and various material medium. When we carry out the actual mode lock analysis, we do take into account of interpaly between all the temporal dynamics of the cavity gain medium, cavity round trip time and the response time of the intra cavity element (saturable absorber, Kerr medium, etc.). that really enforces the locking of the phase of the cavity spontaneous emissions. On a conceptual level, this simplistic representation of the mode locking by Eq.1 ignores all these critical physical processes. When we try to analyze a pulsed field, again we start by representing it very much like this equation, even though we can only detect the square modulus of this complex field and loose a lot of phase related information to the detectors quantum whims and their time constants. The key parameters for a light pulse are as follows. Foremost is the (i) carrier frequency, which cannot be described or imagined without its state of undulation expressed as its (ii) phase. Next is our imagined time finite (iii) carrier envelope that provides the temporal boundary of the field amplitude strength of the undulating E-field. The final parameter is the (iv) state of polarization or the unique plane along which the strength of the E-field gradient undulates. None of these filed characteristics are made self-evident to us by the fields themselves. We do not see light. Light does not see light. Light beams pass through each other without altering each others energy distribution unless there are interacting material molecules (dipoles) within the physical volume of superposition of the beams. In contrast, we can sense the material particles. Material particles sense each other and they cannot pass through each other without interacting with (scattering from) each other. Thus the interpretation of the superposition phenomenon of multiple fields on detectors should not be lumped under the mysterious "wave-particle duality" philosophy. The phenomenon of superposition can be understood better when we focus on the actual process experienced by the detecting dipoles when allowed by QM rules, they respond to and sum all the induced stimulations due to all the superposed fields followed by the proportionate energy absorption giving rise to the fringes we observe. We will present various experimental results to illustrate our arguments. Our position is that such detector behavior driven interpretations rather than the generally implied field-field interaction driven explanations, will help us better understand the ultimate nature of light and hence invent better and newer devices and instruments.

Coupled-resonator waveguide perfect transport single-photon by interatomic dipole-dipole interaction

NASA Astrophysics Data System (ADS)

Yan, Guo-an; Lu, Hua; Qiao, Hao-xue; Chen, Ai-xi; Wu, Wan-qing

2018-06-01

We theoretically investigate single-photon coherent transport in a one-dimensional coupled-resonator waveguide coupled to two quantum emitters with dipole-dipole interactions. The numerical simulations demonstrate that the transmission spectrum of the photon depends on the two atoms dipole-dipole interactions and the photon-atom couplings. The dipole-dipole interactions may change the dip positions in the spectra and the coupling strength may broaden the frequency band width in the transmission spectrum. We further demonstrate that the typical transmission spectra split into two dips due to the dipole-dipole interactions. This phenomenon may be used to manufacture new quantum waveguide devices.

Characterization of the major histopathological components of thyroid nodules using sonographic textural features for clinical diagnosis and management.

PubMed

Chen, Shao-Jer; Yu, Sung-Nien; Tzeng, Jeh-En; Chen, Yen-Ting; Chang, Ku-Yaw; Cheng, Kuo-Sheng; Hsiao, Fu-Tsung; Wei, Chang-Kuo

2009-02-01

In this study, the characteristic sonographic textural feature that represents the major histopathologic components of the thyroid nodules was objectively quantified to facilitate clinical diagnosis and management. A total of 157 regions-of-interest thyroid ultrasound image was recruited in the study. The sonographic system used was the GE LOGIQ 700), (General Electric Healthcare, Chalfant St. Giles, UK). The parameters affecting image acquisition were kept in the same condition for all lesions. Commonly used texture analysis methods were applied to characterize thyroid ultrasound images. Image features were classified according to the corresponding pathologic findings. To estimate their relevance and performance to classification, ReliefF was used as a feature selector. Among the various textural features, the sum average value derived from co-occurrence matrix can well reflect echogenicity and can effectively differentiate between follicles and fibrosis base thyroid nodules. Fibrosis shows lowest echogenicity and lowest difference sum average value. Enlarged follicles show highest echogenicity and difference sum average values. Papillary cancer or follicular tumors show the difference sum average values and echogenicity between. The rule of thumb for the echogenicity is that the more follicles are mixed in, the higher the echo of the follicular tumor and papillary cancer will be and vice versa for fibrosis mixed. Areas with intermediate and lower echo should address the possibility of follicular or papillary neoplasm mixed with either follicles or fibrosis. These areas provide more cellular information for ultrasound guided aspiration

Enhanced and tunable electric dipole-dipole interactions near a planar metal film

NASA Astrophysics Data System (ADS)

Zhou, Lei-Ming; Yao, Pei-Jun; Zhao, Nan; Sun, Fang-Wen

2017-08-01

We investigate the enhanced electric dipole-dipole interaction of surface plasmon polaritons (SPPs) supported by a planar metal film waveguide. By taking two nitrogen-vacancy (NV) center electric dipoles in diamond as an example, both the coupling strength and collective relaxation of two dipoles are studied with the numerical Green Function method. Compared to two-dipole coupling on a planar surface, metal film provides stronger and tunable coupling coefficients. Enhancement of the interaction between coupled NV center dipoles could have applications in both quantum information and energy transfer investigation. Our investigation provides systematic results for experimental applications based on a dipole-dipole interaction mediated with SPPs on a planar metal film.

Transfer of dipolar gas through the discrete localized mode.

PubMed

Bai, Xiao-Dong; Zhang, Ai-Xia; Xue, Ju-Kui

2013-12-01

By considering the discrete nonlinear Schrödinger model with dipole-dipole interactions for dipolar condensate, the existence, the types, the stability, and the dynamics of the localized modes in a nonlinear lattice are discussed. It is found that the contact interaction and the dipole-dipole interactions play important roles in determining the existence, the type, and the stability of the localized modes. Because of the coupled effects of the contact interaction and the dipole-dipole interactions, rich localized modes and their stability nature can exist: when the contact interaction is larger and the dipole-dipole interactions is smaller, a discrete bright breather occurs. In this case, while the on-site interaction can stabilize the discrete breather, the dipole-dipole interactions will destabilize the discrete breather; when both the contact interaction and the dipole-dipole interactions are larger, a discrete kink appears. In this case, both the on-site interaction and the dipole-dipole interactions can stabilize the discrete kink, but the discrete kink is more unstable than the ordinary discrete breather. The predicted results provide a deep insight into the dynamics of blocking, filtering, and transfer of the norm in nonlinear lattices for dipolar condensates.

Light Quark Mass Ratios (mu:md:ms) from Meson and Baryon Mass Splittings

NASA Astrophysics Data System (ADS)

Minkowski, Peter

2013-08-01

The basis of the material discussed is our work in collaboration with Arnulfo Zepeda from 1979 [Nucl. Phys. B164, 25 (1980)]. The ingredients and consequences of this work will be presented, and compared with results obtained from QCD sum rules and lattice simulations of QCD in accordance with chiral expansions. An up-to-date conclusion will not be possible in this paper, but some comments towards such goal will be given in a concluding section.

Deployed Women’s Illness Behaviors While Managing Genitourinary Symptoms: An Exploratory Theoretical Synthesis of Two Qualitative Studies

DTIC Science & Technology

2018-04-21

rules provided opportunities for women to serve in a broad range of military occupations not previously available (Pellerin, 2015). Full integration ...Behavior Model Disease I ._I _____ _ _ 1_L_L_N_e_s_s_e_x_P_E_R_1e_N_c_ e ______ _, ETH NO-CULTURAL CONTEXT External Influences Internal Integration ...disease. Distress refers to the " sum total of psychological factors and somatic sensations, and as such, it was intricately interwoven with meaning

Free-free opacity in dense plasmas with an average atom model

DOE PAGES

Shaffer, Nathaniel R.; Ferris, Natalie G.; Colgan, James Patrick; ...

2017-02-28

A model for the free-free opacity of dense plasmas is presented. The model uses a previously developed average atom model, together with the Kubo-Greenwood model for optical conductivity. This, in turn, is used to calculate the opacity with the Kramers-Kronig dispersion relations. Furthermore, comparisons to other methods for dense deuterium results in excellent agreement with DFT-MD simulations, and reasonable agreement with a simple Yukawa screening model corrected to satisfy the conductivity sum rule.

Free-free opacity in dense plasmas with an average atom model

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

Shaffer, Nathaniel R.; Ferris, Natalie G.; Colgan, James Patrick

A model for the free-free opacity of dense plasmas is presented. The model uses a previously developed average atom model, together with the Kubo-Greenwood model for optical conductivity. This, in turn, is used to calculate the opacity with the Kramers-Kronig dispersion relations. Furthermore, comparisons to other methods for dense deuterium results in excellent agreement with DFT-MD simulations, and reasonable agreement with a simple Yukawa screening model corrected to satisfy the conductivity sum rule.

Measuring Radiofrequency and Microwave Radiation from Varying Signal Strengths

NASA Technical Reports Server (NTRS)

Davis, Bette; Gaul, W. C.

2007-01-01

This viewgraph presentation discusses the process of measuring radiofrequency and microwave radiation from various signal strengths. The topics include: 1) Limits and Guidelines; 2) Typical Variable Standard (IEEE) Frequency Dependent; 3) FCC Standard 47 CFR 1.1310; 4) Compliance Follows Unity Rule; 5) Multiple Sources Contribute; 6) Types of RF Signals; 7) Interfering Radiations; 8) Different Frequencies Different Powers; 9) Power Summing - Peak Power; 10) Contribution from Various Single Sources; 11) Total Power from Multiple Sources; 12) Are You Out of Compliance?; and 13) In Compliance.

Moiré assisted fractional quantum Hall state spectroscopy

DOE PAGES

Wu, Fengcheng; MacDonald, A. H.

2016-12-14

Intra-Landau level excitations in the fractional quantum Hall regime are not accessible via optical absorption measurements. Here we point out that optical probes are enabled by the periodic potentials produced by a moire pattern. Our observation is motivated by the recent observations of fractional quantum Hall incompressible states in moire-patterned graphene on a hexagonal boron nitride substrate, and is theoretically based on f-sum rule considerations supplemented by a perturbative analysis of the influence of the moire potential on many-body states.

Theoretical and experimental characterization of the first hyperpolarizability

NASA Astrophysics Data System (ADS)

Perez-Moreno, Javier

We present a theoretical and experimental study of the molecular susceptibilities. The generalized Thomas-Kuhn sum rules are used to characterize the nonlinear response of organic chromophores in terms of fundamental parameters. The nonlinear optical performance of real molecules is evaluated from the calculation of the quantum limits and Hyper-Rayleigh scattering measurements. Different strategies for the enhancement of nonlinear behavior at the molecular and supramolecular level are evaluated and new paradigms for de design of more efficient nonlinear molecules are proposed.

On the small-x behavior of the orbital angular momentum distributions in QCD

NASA Astrophysics Data System (ADS)

Hatta, Yoshitaka; Yang, Dong-Jing

2018-06-01

We present the numerical solution of the leading order QCD evolution equation for the orbital angular momentum distributions of quarks and gluons and discuss its implications for the nucleon spin sum rule. We observe that at small-x, the gluon helicity and orbital angular momentum distributions are roughly of the same magnitude but with opposite signs, indicating a significant cancellation between them. A similar cancellation occurs also in the quark sector. We explain analytically the reason for this cancellation.

Regulatory light chain mutants linked to heart disease modify the cardiac myosin lever arm.

PubMed

Burghardt, Thomas P; Sikkink, Laura A

2013-02-19

Myosin is the chemomechanical energy transducer in striated heart muscle. The myosin cross-bridge applies impulsive force to actin while consuming ATP chemical energy to propel myosin thick filaments relative to actin thin filaments in the fiber. Transduction begins with ATP hydrolysis in the cross-bridge driving rotary movement of a lever arm converting torque into linear displacement. Myosin regulatory light chain (RLC) binds to the lever arm and modifies its ability to translate actin. Gene sequencing implicated several RLC mutations in heart disease, and three of them are investigated here using photoactivatable GFP-tagged RLC (RLC-PAGFP) exchanged into permeabilized papillary muscle fibers. A single-lever arm probe orientation is detected in the crowded environment of the muscle fiber by using RLC-PAGFP with dipole orientation deduced from the three-spatial dimension fluorescence emission pattern of the single molecule. Symmetry and selection rules locate dipoles in their half-sarcomere, identify those at the minimal free energy, and specify active dipole contraction intermediates. Experiments were performed in a microfluidic chamber designed for isometric contraction, total internal reflection fluorescence detection, and two-photon excitation second harmonic generation to evaluate sarcomere length. The RLC-PAGFP reports apparently discretized lever arm orientation intermediates in active isometric fibers that on average produce the stall force. Disease-linked mutants introduced into RLC move intermediate occupancy further down the free energy gradient, implying lever arms rotate more to reach stall force because mutant RLC increases lever arm shear strain. A lower free energy intermediate occupancy involves a lower energy conversion efficiency in the fiber relating a specific myosin function modification to the disease-implicated mutant.

Effects of the scatter in sunspot group tilt angles on the large-scale magnetic field at the solar surface

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

Jiang, J.; Cameron, R. H.; Schüssler, M., E-mail: jiejiang@nao.cas.cn

The tilt angles of sunspot groups represent the poloidal field source in Babcock-Leighton-type models of the solar dynamo and are crucial for the build-up and reversals of the polar fields in surface flux transport (SFT) simulations. The evolution of the polar field is a consequence of Hale's polarity rules, together with the tilt angle distribution which has a systematic component (Joy's law) and a random component (tilt-angle scatter). We determine the scatter using the observed tilt angle data and study the effects of this scatter on the evolution of the solar surface field using SFT simulations with flux input basedmore » upon the recorded sunspot groups. The tilt angle scatter is described in our simulations by a random component according to the observed distributions for different ranges of sunspot group size (total umbral area). By performing simulations with a number of different realizations of the scatter we study the effect of the tilt angle scatter on the global magnetic field, especially on the evolution of the axial dipole moment. The average axial dipole moment at the end of cycle 17 (a medium-amplitude cycle) from our simulations was 2.73 G. The tilt angle scatter leads to an uncertainty of 0.78 G (standard deviation). We also considered cycle 14 (a weak cycle) and cycle 19 (a strong cycle) and show that the standard deviation of the axial dipole moment is similar for all three cycles. The uncertainty mainly results from the big sunspot groups which emerge near the equator. In the framework of Babcock-Leighton dynamo models, the tilt angle scatter therefore constitutes a significant random factor in the cycle-to-cycle amplitude variability, which strongly limits the predictability of solar activity.« less

Weighted Association Rule Mining for Item Groups with Different Properties and Risk Assessment for Networked Systems

NASA Astrophysics Data System (ADS)

Kim, Jungja; Ceong, Heetaek; Won, Yonggwan

In market-basket analysis, weighted association rule (WAR) discovery can mine the rules that include more beneficial information by reflecting item importance for special products. In the point-of-sale database, each transaction is composed of items with similar properties, and item weights are pre-defined and fixed by a factor such as the profit. However, when items are divided into more than one group and the item importance must be measured independently for each group, traditional weighted association rule discovery cannot be used. To solve this problem, we propose a new weighted association rule mining methodology. The items should be first divided into subgroups according to their properties, and the item importance, i.e. item weight, is defined or calculated only with the items included in the subgroup. Then, transaction weight is measured by appropriately summing the item weights from each subgroup, and the weighted support is computed as the fraction of the transaction weights that contains the candidate items relative to the weight of all transactions. As an example, our proposed methodology is applied to assess the vulnerability to threats of computer systems that provide networked services. Our algorithm provides both quantitative risk-level values and qualitative risk rules for the security assessment of networked computer systems using WAR discovery. Also, it can be widely used for new applications with many data sets in which the data items are distinctly separated.

Analysis 320 coal mine accidents using structural equation modeling with unsafe conditions of the rules and regulations as exogenous variables.

PubMed

Zhang, Yingyu; Shao, Wei; Zhang, Mengjia; Li, Hejun; Yin, Shijiu; Xu, Yingjun

2016-07-01

Mining has been historically considered as a naturally high-risk industry worldwide. Deaths caused by coal mine accidents are more than the sum of all other accidents in China. Statistics of 320 coal mine accidents in Shandong province show that all accidents contain indicators of "unsafe conditions of the rules and regulations" with a frequency of 1590, accounting for 74.3% of the total frequency of 2140. "Unsafe behaviors of the operator" is another important contributory factor, which mainly includes "operator error" and "venturing into dangerous places." A systems analysis approach was applied by using structural equation modeling (SEM) to examine the interactions between the contributory factors of coal mine accidents. The analysis of results leads to three conclusions. (i) "Unsafe conditions of the rules and regulations," affect the "unsafe behaviors of the operator," "unsafe conditions of the equipment," and "unsafe conditions of the environment." (ii) The three influencing factors of coal mine accidents (with the frequency of effect relation in descending order) are "lack of safety education and training," "rules and regulations of safety production responsibility," and "rules and regulations of supervision and inspection." (iii) The three influenced factors (with the frequency in descending order) of coal mine accidents are "venturing into dangerous places," "poor workplace environment," and "operator error." Copyright © 2016 Elsevier Ltd. All rights reserved.

A process-based investigation into the impact of the Congo basin deforestation on surface climate

NASA Astrophysics Data System (ADS)

Bell, Jean P.; Tompkins, Adrian M.; Bouka-Biona, Clobite; Sanda, I. Seidou

2015-06-01

The sensitivity of climate to the loss of the Congo basin rainforest through changes in land cover properties is examined using a regional climate model. The complete removal of the Congo basin rainforest results in a dipole rainfall anomaly pattern, characterized by a decrease (˜-42%) in rainfall over the western Congo and an increase (˜10%) in the basin's eastern part. Three further experiments systematically examine the individual response to the changes in albedo, surface roughness, and evapotranspiration efficiency that accompany deforestation. The increased albedo (˜) caused by the Congo basin rainforest clearance results in cooler and drier climate conditions over the entire basin. The drying is accompanied with a reduction in available surface energy. Reducing evapotranspiration efficiency or roughness length produces similar positive air temperature anomaly patterns. The decreased evapotranspiration efficiency leads to a dipole response in rainfall, similar to that resulting from a reduced surface roughness following Congo basin rainforest clearance. This precipitation anomaly pattern is strongly linked to the change in low-level water vapor transport, the influence of the Rift valley highlands, and the spatial pattern of water recycling activity. The climate responds linearly to the separate albedo, surface roughness, and evapotranspiration efficiency changes, which can be summed to produce a close approximation to the impact of the full deforestation experiment. It is suggested that the widely contrasting climate responses to deforestation in the literature could be partly due to the relative magnitude of change of the radiative and nonradiative parameterizations in their respective land surface schemes.

Deviations from idealised geometries part 3: approximately tetrahedral molecules of form MX 2Y 2 studied by SCF and MP2 calculations

NASA Astrophysics Data System (ADS)

Palmer, Michael H.

1997-03-01

The relatively minor deviations from true tetrahedral geometry for molecules of type MX 2Y 2 where M is tetravalent, and X, Y are either H, Me or halogen are discussed, in the light of ab initio calculations of equilibrium geometry with a large (triple zeta valence + polarisation) basis, at both the SCF and MP2 levels. The results are compared with known experimental structural and dipole moment data; in most cases a very close correlation with experiment is found, with slight improvements in the MP2 data. The study is coupled with a localised orbital study of relevance to Bent's Rule.

Fine- and hyperfine-structure effects in molecular photoionization. I. General theory and direct photoionization

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

Germann, Matthias; Willitsch, Stefan, E-mail: stefan.willitsch@unibas.ch

2016-07-28

We develop a model for predicting fine- and hyperfine intensities in the direct photoionization of molecules based on the separability of electron and nuclear spin states from vibrational-electronic states. Using spherical tensor algebra, we derive highly symmetrized forms of the squared photoionization dipole matrix elements from which we derive the salient selection and propensity rules for fine- and hyperfine resolved photoionizing transitions. Our theoretical results are validated by the analysis of the fine-structure resolved photoelectron spectrum of O{sub 2} reported by Palm and Merkt [Phys. Rev. Lett. 81, 1385 (1998)] and are used for predicting hyperfine populations of molecular ionsmore » produced by photoionization.« less

Variational Calculation of the Ground State of Closed-Shell Nuclei Up to $A$ = 40

DOE PAGES

Lonardoni, Diego; Lovato, Alessandro; Pieper, Steven C.; ...

2017-08-31

Variational calculations of ground-state properties of 4He, 16O and 40Ca are carried out employing realistic phenomenological two- and three-nucleon potentials. The trial wave function includes twoand three-body correlations acting on a product of single-particle determinants. Expectation values are evaluated with a cluster expansion for the spin-isospin dependent correlations considering up to five-body cluster terms. The optimal wave function is obtained by minimizing the energy expectation value over a set of up to 20 parameters by means of a nonlinear optimization library. We present results for the binding energy, charge radius, point density, single-nucleon momentum distribution, charge form factor, and Coulombmore » sum rule. We find that the employed three-nucleon interaction becomes repulsive for A ≥ 16. In 16O the inclusion of such a force provides a better description of the properties of the nucleus. In 40Ca instead, the repulsive behavior of the three-body interaction fails to reproduce experimental data for the charge radius and the charge form factor. We find that the high-momentum region of the momentum distributions, determined by the short-range terms of nuclear correlations, exhibit a universal behavior independent of the particular nucleus. The comparison of the Coulomb sum rules for 4He, 16O, and 40Ca reported in this work will help elucidate in-medium modifications of the nucleon form factors.« less

0+ tetraquark states from improved QCD sum rules: delving into X(5568)

NASA Astrophysics Data System (ADS)

Zhang, Jian-Rong; Zou, Jing-Lan; Wu, Jin-Yun

2018-04-01

In order to investigate the possibility of the recently observed X(5568) being a 0+ tetraquark state, we make an improvement to the study of the related various configuration states in the framework of the QCD sum rules. Particularly, to ensure the quality of the analysis, condensates up to dimension 12 are included to inspect the convergence of operator product expansion (OPE) and improve the final results of the studied states. We note that some condensate contributions could play an important role on the OPE side. By releasing the rigid OPE convergence criterion, we arrive at the numerical value {5.57}-0.23+0.35 {{GeV}} for the scalar-scalar diquark-antidiquark 0+ state, which agrees with the experimental data for the X(5568) and could support its interpretation in terms of a 0+ tetraquark state with the scalar-scalar configuration. The corresponding result for the axial-axial current is calculated to be {5.77}-0.33+0.44 {{GeV}}, which is still consistent with the mass of X(5568) in view of the uncertainty. The feasibility of X(5568) being a tetraquark state with the axial-axial configuration therefore cannot be definitely excluded. For the pseudoscalar-pseudoscalar and the vector-vector cases, their unsatisfactory OPE convergence make it difficult to find reasonable work windows to extract the hadronic information. Supported by National Natural Science Foundation of China (11475258, 11105223, 11675263) and the Project in NUDT for Excellent Youth Talents

Spin and orbital magnetic moments of Fe and Co in Co/Fe and Fe/Co multilayers on Si from L2,3 edge X-ray Magnetic Circular Dichroism Spectroscopy

NASA Astrophysics Data System (ADS)

Vemuru, Krishnamurthy; Rosenberg, Richard; Mankey, Gary

Nanostructured FeCo thin films are interesting for magnetic recording applications due to their high saturation magnetization, high Curie temperature and low magnetocrystalline anisotropy. It is desirable to know how the magnetism is modified by the nanostructrure. We report Fe L 2 , 3 edge and Co L2 , 3 edge x-ray magnetic circular dichroism (XMCD) investigations of element specific spin and orbital magnetism of Fe and Co in two multilayer samples: (S1) Si/SiO2/[Co 0.8 nm/Fe 1.6 nm]x32/W (2nm) and (S2) Si/SiO2/[Co 1.6 nm/Fe 0.8 nm]x32/W (2nm) thin films at room temperature. Sum rule analysis of XMCD at Fe L2 , 3 edge in sample S1 shows that the orbital moment of Fe is strongly enhanced and the spin moment is strongly reduced as compared to the values found in bulk Fe. Details of sum rule analysis will be presented to compare and contrast spin magnetic moments and orbital magnetic moments of Fe and Co in the two multilayer samples. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357.

Multiple symbol partially coherent detection of MPSK

NASA Technical Reports Server (NTRS)

Simon, M. K.; Divsalar, D.

1992-01-01

It is shown that by using the known (or estimated) value of carrier tracking loop signal to noise ratio (SNR) in the decision metric, it is possible to improve the error probability performance of a partially coherent multiple phase-shift-keying (MPSK) system relative to that corresponding to the commonly used ideal coherent decision rule. Using a maximum-likeihood approach, an optimum decision metric is derived and shown to take the form of a weighted sum of the ideal coherent decision metric (i.e., correlation) and the noncoherent decision metric which is optimum for differential detection of MPSK. The performance of a receiver based on this optimum decision rule is derived and shown to provide continued improvement with increasing length of observation interval (data symbol sequence length). Unfortunately, increasing the observation length does not eliminate the error floor associated with the finite loop SNR. Nevertheless, in the limit of infinite observation length, the average error probability performance approaches the algebraic sum of the error floor and the performance of ideal coherent detection, i.e., at any error probability above the error floor, there is no degradation due to the partial coherence. It is shown that this limiting behavior is virtually achievable with practical size observation lengths. Furthermore, the performance is quite insensitive to mismatch between the estimate of loop SNR (e.g., obtained from measurement) fed to the decision metric and its true value. These results may be of use in low-cost Earth-orbiting or deep-space missions employing coded modulations.

Precision measurement of quasi-elastic transverse and longitudinal response functions in the range 0.55 GeV/c lte |q-right arrow| lte 1.0 GeV/c

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

Atac, Hamza

The Coulomb Sum is defined by the quasi-elastic nucleon knock-out process and it is the integration of the longitudinal response function over the energy loss of the incident electron. The Coulomb sum goes to the total charge at large q. The existing measurements of the Coulomb Sum Rule show disagreement with the theoretical calculations for the medium and heavy nuclei. To find the reason behind the disagreement might answer the question of whether the properties of the nucleons are affected by the nuclear medium or not. In order to determine the Coulomb Sum in nuclei, a precision measurement of inclusivemore » electron scattering in the quasi-elastic region was performed at the Thomas Jefferson National Accelerator Facility. Incident electrons with energies ranging from 0.4 GeV to 4 GeV scattered off 4He,12C,56Fe and 208Pb nuclei at four scattering angles (15 deg.; 60 deg.; 90 deg.; 120 deg.) and scattered energies ranging from 0.1 GeV to 4 GeV. The Born cross sections were extracted for the Left High Resolution Spectrometer (LHRS) and the Right High Resolution Spectrometer 56Fe data. The Rosenbluth separation was performed to extract the transverse and longitudinal response functions at 650 MeV three-momentum transfer. The preliminary results of the longitudinal and transverse functions were extracted for 56Fe target at 650 MeV three-momentum transfer.« less

A polarizable dipole-dipole interaction model for evaluation of the interaction energies for N-H···O=C and C-H···O=C hydrogen-bonded complexes.

PubMed

Li, Shu-Shi; Huang, Cui-Ying; Hao, Jiao-Jiao; Wang, Chang-Sheng

2014-03-05

In this article, a polarizable dipole-dipole interaction model is established to estimate the equilibrium hydrogen bond distances and the interaction energies for hydrogen-bonded complexes containing peptide amides and nucleic acid bases. We regard the chemical bonds N-H, C=O, and C-H as bond dipoles. The magnitude of the bond dipole moment varies according to its environment. We apply this polarizable dipole-dipole interaction model to a series of hydrogen-bonded complexes containing the N-H···O=C and C-H···O=C hydrogen bonds, such as simple amide-amide dimers, base-base dimers, peptide-base dimers, and β-sheet models. We find that a simple two-term function, only containing the permanent dipole-dipole interactions and the van der Waals interactions, can produce the equilibrium hydrogen bond distances compared favorably with those produced by the MP2/6-31G(d) method, whereas the high-quality counterpoise-corrected (CP-corrected) MP2/aug-cc-pVTZ interaction energies for the hydrogen-bonded complexes can be well-reproduced by a four-term function which involves the permanent dipole-dipole interactions, the van der Waals interactions, the polarization contributions, and a corrected term. Based on the calculation results obtained from this polarizable dipole-dipole interaction model, the natures of the hydrogen bonding interactions in these hydrogen-bonded complexes are further discussed. Copyright © 2013 Wiley Periodicals, Inc.

Excited Nucleons and Hadron Structure - Proceedings of the Nstar 2000 Conference

NASA Astrophysics Data System (ADS)

Burkert, V. D.; Elouadrhiri, L.; Kelly, J. J.; Minehart, R. C.

The Table of Contents for the book is as follows: * Probing the Structure of Nucleons in the Resonance Region * Pion Photoproduction Results from MAMI * Pion Production and Compton Scattering at LEGS * Electroproduction Multipoles from ELSA * Baryon Resonance Production at Jefferson Lab at High Q2 * A Dynamical Model for the Resonant Multipoles and the Δ Structure * Relations between N and Δ Electromagnetic Form Factors * Measurement of the Recoil Polarization in the [p(ěc e ,{e^prime}ěc p ){π ^0}] Reaction at the Energy of the Δ(1232) Resonance * Electroproduction Results from CLAS * S11 (1535) Resonance Production at Jefferson Lab at High Q2 * η and η' Electro- and Photoproduction with the CEBAF Large Acceptance Spectrometer * η Production in Hadronic Interactions * Electromagnetic Production of η and η' Mesons * The Crystal Barrel Experiment at ELSA * Measurement of π-p → Neutrals Using the Crystal Ball * π+π0 and η Photoproduction at GRAAL * Partial Wave Analysis of Pion Photoproduction with Constraints from Fixed-t Dispersion Relations * N* Resonances in e+e- Collisions at BEPC * What is the Structure of the Roper Resonance? * Hybrid Baryon Signatures * Mixing Angles Determination via the Process γp → ηp * SU(6) Breaking Effects in the Nucleon Elastic Electromagnetic Form Factors * The Hypercentral Constituent Quark Model * Baryon Resonance Decays Within Constituent Quark Models * Pion Production Model - Connection between Dynamics and Quark Models * N* Investigation via Two Pion Electroproduction with the CLAS Detector at Jefferson Laboratory * Isobar Model for Studies of N* Excitation in Charged Double Pion Production by Real and Virtual Photons * Double Pion Photoproduction in the Second Resonance Region * CLAS Electroproduction of ω(783) Mesons * Electromagnetic Production of Vector Mesons at Low Energies * Polarized Target Developments for GRAAL and Prospects * Analytic Structure of a Multichannel Model * Missing Nucleon Resonances in Kaon Production with Pions and Photons * Hyperon Electroproduction with CLAS * From Bjorken to Drell-Hearn-Gerasimov Sum Rules * GDH Measurements at Mainz * Double Polarization Measurements in Inclusive Inelastic e - p Scattering * Measurement of Inclusive Spin Asymmetries and Sum Rules on 3He and the Neutron * Polarization and Out-of-Plane Responses in Pion and ETA Electroproduction * Polarization Observables in π+ Electroproduction with CLAS * Pion Electroproduction on the Nucleon and the Generalized GDH Sum Rule * Virtual Compton Scattering in the Resonance Region * What We Know about the Theoretical Foundation of Duality in Electron Scattering * Hadron Structure in Lattice QCD: Exploring the Gluon Wave Functional * N* Spectrum in Lattice QCD * Baryon Spectrum in the Large Nc Limit * Deeply Virtual Photon and Meson Electroproduction * Why N*'s are Important * Participant List

Hot electron energy relaxation in lattice-matched InAlN/AlN/GaN heterostructures: The sum rules for electron-phonon interactions and hot-phonon effect

NASA Astrophysics Data System (ADS)

Zhang, J.-Z.; Dyson, A.; Ridley, B. K.

2015-01-01

Using the dielectric continuum (DC) and three-dimensional phonon (3DP) models, energy relaxation (ER) of the hot electrons in the quasi-two-dimensional channel of lattice-matched InAlN/AlN/GaN heterostructures is studied theoretically, taking into account non-equilibrium polar optical phonons, electron degeneracy, and screening from the mobile electrons. The electron power dissipation (PD) and ER time due to both half-space and interface phonons are calculated as functions of the electron temperature Te using a variety of phonon lifetime values from experiment, and then compared with those evaluated by the 3DP model. Thereby, particular attention is paid to examination of the 3DP model to use for the hot-electron relaxation study. The 3DP model yields very close results to the DC model: With no hot phonons or screening, the power loss calculated from the 3DP model is 5% smaller than the DC power dissipation, whereas slightly larger 3DP power loss (by less than 4% with a phonon lifetime from 0.1 to 1 ps) is obtained throughout the electron temperature range from room temperature to 2500 K after including both the hot-phonon effect (HPE) and screening. Very close results are obtained also for ER time with the two phonon models (within a 5% of deviation). However, the 3DP model is found to underestimate the HPE by 9%. The Mori-Ando sum rule is restored by which it is proved that the PD values obtained from the DC and 3DP models are in general different in the spontaneous phonon emission process, except when scattering with interface phonons is sufficiently weak, or when the degenerate modes condition is imposed, which is also consistent with Register's scattering rate sum rule. The discrepancy between the DC and 3DP results is found to be caused by how much the high-energy interface phonons contribute to the ER: their contribution is enhanced in the spontaneous emission process but is dramatically reduced after including the HPE. Our calculation with both phonon models has obtained a great fall in ER time at low electron temperatures (Te < 750 K) and slow decrease at the high temperatures with the use of decreasing phonon lifetime with Te. The calculated temperature dependence of the relaxation time and the high-temperature relaxation time ˜0.09 ps are in good agreement with experimental results.

Improving the Optical Trapping Efficiency in the 225Ra Electric Dipole Moment Experiment via Monte Carlo Simulation

NASA Astrophysics Data System (ADS)

Fromm, Steven

2017-09-01

In an effort to study and improve the optical trapping efficiency of the 225Ra Electric Dipole Moment experiment, a fully parallelized Monte Carlo simulation of the laser cooling and trapping apparatus was created at Argonne National Laboratory and now maintained and upgraded at Michigan State University. The simulation allows us to study optimizations and upgrades without having to use limited quantities of 225Ra (15 day half-life) in experiment's apparatus. It predicts a trapping efficiency that differs from the observed value in the experiment by approximately a factor of thirty. The effects of varying oven geometry, background gas interactions, laboratory magnetic fields, MOT laser beam configurations and laser frequency noise were studied and ruled out as causes of the discrepancy between measured and predicted values of the overall trapping efficiency. Presently, the simulation is being used to help optimize a planned blue slower laser upgrade in the experiment's apparatus, which will increase the overall trapping efficiency by up to two orders of magnitude. This work is supported by Michigan State University, the Director's Research Scholars Program at the National Superconducting Cyclotron Laboratory, and the U.S. DOE, Office of Science, Office of Nuclear Physics, under Contract DE-AC02-06CH11357.

Assembly Modulated by Particle Position and Shape: A New Concept in Self-Assembly.

PubMed

Tavacoli, Joe W; Heuvingh, Julien; Du Roure, Olivia

2017-11-10

In this communication we outline how the bespoke arrangements and design of micron-sized superparamagnetic shapes provide levers to modulate their assembly under homogeneous magnetic fields. We label this new approach, 'assembly modulated by particle position and shape' (APPS). Specifically, using rectangular lattices of superparamagnetic micron-sized cuboids, we construct distinct microstructures by adjusting lattice pitch and angle of array with respect to a magnetic field. Broadly, we find two modes of assembly: (1) immediate 2D jamming of the cuboids as they rotate to align with the applied field (rotation-induced jamming) and (2) aggregation via translation after their full alignment (dipole-dipole assembly). The boundary between these two assembly pathways is independent on field strength being solely a function of the cuboid's dimensions, lattice pitch, and array angle with respect to field-a relationship which we capture, along with other features of the assembly process, in a 'phase diagram'. In doing so, we set out initial design rules to build custom made assemblies. Moreover, these assemblies can be made flexible thanks to the hinged contacts of their particle building blocks. This flexibility, combined with the superparamagnetic nature of the architectures, renders our assembly method particularly appropriate for the construction of complex actuators at a scale hitherto not possible.

Frequency selection rule for high definition and high frame rate Lissajous scanning.

PubMed

Hwang, Kyungmin; Seo, Yeong-Hyeon; Ahn, Jinhyo; Kim, Pilhan; Jeong, Ki-Hun

2017-10-26

Lissajous microscanners are very attractive in compact laser scanning applications such as endomicroscopy or pro-projection display owing to high mechanical stability and low operating voltages. The scanning frequency serves as a critical factor for determining the scanning imaging quality. Here we report the selection rule of scanning frequencies that can realize high definition and high frame-rate (HDHF) full-repeated Lissajous scanning imaging. The fill factor (FF) monotonically increases with the total lobe number of a Lissajous curve, i.e., the sum of scanning frequencies divided by the great common divisor (GCD) of bi-axial scanning frequencies. The frames per second (FPS), called the pattern repeated rate or the frame rate, linearly increases with GCD. HDHF Lissajous scanning is achieved at the bi-axial scanning frequencies, where the GCD has the maximum value among various sets of the scanning frequencies satisfying the total lobe number for a target FF. Based on this selection rule, the experimental results clearly demonstrate that conventional Lissajous scanners substantially increase both FF and FPS by slightly modulating the scanning frequencies at near the resonance within the resonance bandwidth of a Lissajous scanner. This selection rule provides a new guideline for HDHF Lissajous scanning in compact laser scanning systems.

The role of angular momentum in the superrotor theory for rovibrational motion of extremely flexible molecules

NASA Astrophysics Data System (ADS)

Schmiedt, Hanno; Jensen, Per; Schlemmer, Stephan

2017-12-01

Recently, we proposed a novel approach to the description of the rotation-vibration motion for extremely flexible molecules (Schmiedt et al., 2016, 2017). Such molecules have multiple very "soft" vibrational modes and so, they lack a well-defined equilibrium structure. We have applied the new superrotor model to the prototype example of an extremely flexible molecule, CH5+, for which we combine two, essentially free vibrational modes (describing internal rotation) with the over-all rotation of the molecule and consider the resulting motion as a free rotation in five-dimensional space, with a Hamiltonian whose symmetry is described by SO(5), the five-dimensional rotation group. In the present work we discuss the correlation between the superrotor energies and those obtained in the more usual situation of the internal and over-all rotations being separable, and we give an initial discussion of the selection rules for electric dipole transitions obtained in the superrotor approach. Such selection rules are required for a detailed comparison between the superrotor predictions and the available, experimentally derived energy spacings (Asvany et al., 2015; Brackertz, 2016).

Constraints on exotic dipole-dipole couplings between electrons at the micron scale

NASA Astrophysics Data System (ADS)

Kotler, Shlomi; Ozeri, Roee; Jackson Kimball, Derek

2015-05-01

Until recently, the magnetic dipole-dipole coupling between electrons had not been directly observed experimentally. This is because at the atomic scale dipole-dipole coupling is dominated by the exchange interaction and at larger distances the dipole-dipole coupling is overwhelmed by ambient magnetic field noise. In spite of these challenges, the magnetic dipole-dipole interaction between two electron spins separated by 2.4 microns was recently measured using the valence electrons of trapped Strontium ions [S. Kotler, N. Akerman, N. Navon, Y. Glickman, and R. Ozeri, Nature 510, 376 (2014)]. We have used this measurement to directly constrain exotic dipole-dipole interactions between electrons at the micron scale. For light bosons (mass 0.1 eV), we find that coupling constants describing pseudoscalar and axial-vector mediated interactions must be | gPegPe/4 πℏc | <= 1 . 5 × 10-3 and | gAegAe/4 πℏc | <= 1 . 2 × 10-17 , respectively, at the 90% confidence level. These bounds significantly improve on previous constraints in this mass range: for example, the constraints on axial-vector interactions are six orders of magnitude stronger than electron-positron constraints based on positronium spectroscopy. Supported by the National Science Foundation, I-Core: the Israeli excellence center, and the European Research Council.

Ideal Magnetic Dipole Scattering

NASA Astrophysics Data System (ADS)

Feng, Tianhua; Xu, Yi; Zhang, Wei; Miroshnichenko, Andrey E.

2017-04-01

We introduce the concept of tunable ideal magnetic dipole scattering, where a nonmagnetic nanoparticle scatters light as a pure magnetic dipole. High refractive index subwavelength nanoparticles usually support both electric and magnetic dipole responses. Thus, to achieve ideal magnetic dipole scattering one has to suppress the electric dipole response. Such a possibility was recently demonstrated for the so-called anapole mode, which is associated with zero electric dipole scattering. By spectrally overlapping the magnetic dipole resonance with the anapole mode, we achieve ideal magnetic dipole scattering in the far field with tunable strong scattering resonances in the near infrared spectrum. We demonstrate that such a condition can be realized at least for two subwavelength geometries. One of them is a core-shell nanosphere consisting of a Au core and silicon shell. It can be also achieved in other geometries, including nanodisks, which are compatible with current nanofabrication technology.

Tree Branching: Leonardo da Vinci's Rule versus Biomechanical Models

PubMed Central

Minamino, Ryoko; Tateno, Masaki

2014-01-01

This study examined Leonardo da Vinci's rule (i.e., the sum of the cross-sectional area of all tree branches above a branching point at any height is equal to the cross-sectional area of the trunk or the branch immediately below the branching point) using simulations based on two biomechanical models: the uniform stress and elastic similarity models. Model calculations of the daughter/mother ratio (i.e., the ratio of the total cross-sectional area of the daughter branches to the cross-sectional area of the mother branch at the branching point) showed that both biomechanical models agreed with da Vinci's rule when the branching angles of daughter branches and the weights of lateral daughter branches were small; however, the models deviated from da Vinci's rule as the weights and/or the branching angles of lateral daughter branches increased. The calculated values of the two models were largely similar but differed in some ways. Field measurements of Fagus crenata and Abies homolepis also fit this trend, wherein models deviated from da Vinci's rule with increasing relative weights of lateral daughter branches. However, this deviation was small for a branching pattern in nature, where empirical measurements were taken under realistic measurement conditions; thus, da Vinci's rule did not critically contradict the biomechanical models in the case of real branching patterns, though the model calculations described the contradiction between da Vinci's rule and the biomechanical models. The field data for Fagus crenata fit the uniform stress model best, indicating that stress uniformity is the key constraint of branch morphology in Fagus crenata rather than elastic similarity or da Vinci's rule. On the other hand, mechanical constraints are not necessarily significant in the morphology of Abies homolepis branches, depending on the number of daughter branches. Rather, these branches were often in agreement with da Vinci's rule. PMID:24714065

Tree branching: Leonardo da Vinci's rule versus biomechanical models.

PubMed

Minamino, Ryoko; Tateno, Masaki

2014-01-01

This study examined Leonardo da Vinci's rule (i.e., the sum of the cross-sectional area of all tree branches above a branching point at any height is equal to the cross-sectional area of the trunk or the branch immediately below the branching point) using simulations based on two biomechanical models: the uniform stress and elastic similarity models. Model calculations of the daughter/mother ratio (i.e., the ratio of the total cross-sectional area of the daughter branches to the cross-sectional area of the mother branch at the branching point) showed that both biomechanical models agreed with da Vinci's rule when the branching angles of daughter branches and the weights of lateral daughter branches were small; however, the models deviated from da Vinci's rule as the weights and/or the branching angles of lateral daughter branches increased. The calculated values of the two models were largely similar but differed in some ways. Field measurements of Fagus crenata and Abies homolepis also fit this trend, wherein models deviated from da Vinci's rule with increasing relative weights of lateral daughter branches. However, this deviation was small for a branching pattern in nature, where empirical measurements were taken under realistic measurement conditions; thus, da Vinci's rule did not critically contradict the biomechanical models in the case of real branching patterns, though the model calculations described the contradiction between da Vinci's rule and the biomechanical models. The field data for Fagus crenata fit the uniform stress model best, indicating that stress uniformity is the key constraint of branch morphology in Fagus crenata rather than elastic similarity or da Vinci's rule. On the other hand, mechanical constraints are not necessarily significant in the morphology of Abies homolepis branches, depending on the number of daughter branches. Rather, these branches were often in agreement with da Vinci's rule.

Intensity measurements for the /2, O/ gamma-band of O2, b 1Sigma-g/+/ - X 3Sigma-g/-/

NASA Technical Reports Server (NTRS)

Miller, J. H.; Giver, L. P.; Boese, R. W.

1976-01-01

Line intensities for the P sub P and P sub Q branches of the (2-O) vibrational band of the magnetic dipole electronic transition for the oxygen red system at 6280 A were measured, and the sum of the R sub R and R sub Q branch intensities was taken. A large number of repetitive spectral scans were required for accuracy, because of low absorption values even at optical path lengths from 300 to 600 m. A total of 557 individual measurements of P-branch lines yielded an intensity value for the P-branches, and equivalent widths for 24 spectral scans yielded an intensity value for the R-branch. R-branch to P-branch intensity ratios were taken for the A-band, B-band, and gamma-band (respectively, O-O at 7620 A, 1-O at 6880 A, and 2-O at 6280 A). Intensities for some rotational lines are found, and effects of combined rotation-vibration interaction are probed.

Electron-impact total ionization cross sections of DNA sugar-phosphate backbone and an additivity principle

NASA Technical Reports Server (NTRS)

Huo, Winifred M.; Dateo, Christopher E.

2005-01-01

The improved binary-encounter dipole (iBED) model [W.M. Huo, Phys. Rev. A64, 042719-1 (2001)l is used to study the total ionization cross sections of the DNA sugar-phosphate backbone by electron impact. Calculations using neutral fragments found that the total ionization cross sections of C3' - and C5', -deoxyribose-phospate, two conformers of the sugar-phosphate backbone, are close to each other. Furthermore, the sum of the ionization cross sections of the separate deoxyribose and phosphate fragments is in close agreement with the C3' - and C5" -deoxyribose-phospate cross sections, differing by less than 10%. The result implies that certain properties of the-DNA, like the total singly ionization cross section, are localized properties and a building-up or additivity principle may apply. This allows us to obtain accurate properties of larger molecular systems built up from the results of smaller subsystem fragments. Calculations are underway using a negatively charged sugar-phosphate backbone with a metal counter-ion.

Electron-Impact Ionization and Dissociative Ionization of Biomolecules

NASA Technical Reports Server (NTRS)

Huo, Winifred M.; Chaban, Galina M.; Dateo, Christopher E.

2006-01-01

It is well recognized that secondary electrons play an important role in radiation damage to humans. Particularly important is the damage of DNA by electrons, potentially leading to mutagenesis. Molecular-level study of electron interaction with DNA provides information on the damage pathways and dominant mechanisms. Our study of electron-impact ionization of DNA fragments uses the improved binary-encounter dipole model and covers DNA bases, sugar phosphate backbone, and nucleotides. An additivity principle is observed. For example, the sum of the ionization cross sections of the separate deoxyribose and phosphate fragments is in close agreement with the C3(sup prime)- and C5 (sup prime)-deoxyribose-phospate cross sections, differing by less than 5%. Investigation of tandem double lesion initiated by electron-impact dissociative ionization of guanine, followed by proton reaction with the cytosine in the Watson-Crick pair, is currently being studied to see if tandem double lesion can be initiated by electron impact. Up to now only OH-induced tandem double lesion has been studied.

RECOLA2: REcursive Computation of One-Loop Amplitudes 2

NASA Astrophysics Data System (ADS)

Denner, Ansgar; Lang, Jean-Nicolas; Uccirati, Sandro

2018-03-01

We present the Fortran95 program RECOLA2 for the perturbative computation of next-to-leading-order transition amplitudes in the Standard Model of particle physics and extended Higgs sectors. New theories are implemented via model files in the 't Hooft-Feynman gauge in the conventional formulation of quantum field theory and in the Background-Field method. The present version includes model files for Two-Higgs-Doublet Model and the Higgs-Singlet Extension of the Standard Model. We support standard renormalization schemes for the Standard Model as well as many commonly used renormalization schemes in extended Higgs sectors. Within these models the computation of next-to-leading-order polarized amplitudes and squared amplitudes, optionally summed over spin and colour, is fully automated for any process. RECOLA2 allows the computation of colour- and spin-correlated leading-order squared amplitudes that are needed in the dipole subtraction formalism. RECOLA2 is publicly available for download at http://recola.hepforge.org.

Exact mode volume and Purcell factor of open optical systems

NASA Astrophysics Data System (ADS)

Muljarov, E. A.; Langbein, W.

2016-12-01

The Purcell factor quantifies the change of the radiative decay of a dipole in an electromagnetic environment relative to free space. Designing this factor is at the heart of photonics technology, striving to develop ever smaller or less lossy optical resonators. The Purcell factor can be expressed using the electromagnetic eigenmodes of the resonators, introducing the notion of a mode volume for each mode. This approach allows an analytic treatment, reducing the Purcell factor and other observables to sums over eigenmode resonances. Calculating the mode volumes requires a correct normalization of the modes. We introduce an exact normalization of modes, not relying on perfectly matched layers. We present an analytic theory of the Purcell effect based on this exact mode normalization and the resulting effective mode volume. We use a homogeneous dielectric sphere in vacuum, which is analytically solvable, to exemplify these findings. We furthermore verify the applicability of the normalization to numerically determined modes of a finite dielectric cylinder.

Iron abundance and magnetic permeability of the moon

NASA Technical Reports Server (NTRS)

Parkin, C. W.; Daily, W. D.; Dyal, P.

1974-01-01

A larger set of simultaneous data from the Apollo 12 lunar surface magnetometer and the Explorer 35 Ames magnetometer are used to construct a whole-moon hysteresis curve, from which a new value of global lunar permeability is determined to be mu = 1.012 + or - 0.006. The corresponding global induced dipole moment is 2.1 x 10 to the 18th power gauss-cu cm for typical inducing fields of .0001 gauss in the lunar environment. From the permeability measurement, lunar free iron abundance is determined to be 2.5 + or - 2.0 wt. %. Total iron abundance (sum of iron in the ferromagnetic and paramagnetic states) is calculated for two assumed compositional models of the lunar interior: a free iron/orthopyroxene lunar composition and a free iron/olivine composition. The overall lunar total iron abundance is determined to be 9.0 + or - 4.7 wt. %. Other lunar models with a small iron core and with a shallow iron-rich layer are discussed in light of the measured global permeability.

The Rydberg electronic transitions of the hydrogen molecule

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

Babb, J.F.; Chang, E.S.

1992-01-01

Transition energies and relative line strengths, without Boltzmann weighting, for the electric dipole transitions between Rydberg states n{prime}L{prime} and nL of the hydrogen molecule (one electron in a near-hydrogenic state of high n and L, with n the principal quantum number and L the orbital angular momentum quantum number of the electron) are calculated. Since the H{sup +}{sub 2} core is loosely coupled to the Rydberg electron, numerous lines occur, depending on the vector sum of L and the core rotational angular momentum. For the core vibrational quantum numbers v = 0 to 5 the strongest lines among the P,more » Q, and R branches for the lowest 12 core rotational levels are given for the particular transition arrays 6h-5g, 8i-6h, 7i-6h, 8k-7i, and 9l-8k, for which transitions occur in the wave number range 350 to 1,400 cm {sup {minus}1}.« less

Fractional Quantum Hall Effect in Infinite-Layer Systems

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

Naud, J. D.; Pryadko, Leonid P.; Sondhi, S. L.

2000-12-18

Stacked two dimensional electron systems in transverse magnetic fields exhibit three dimensional fractional quantum Hall phases. We analyze the simplest such phases and find novel bulk properties, e.g., irrational braiding. These phases host ''one and a half'' dimensional surface phases in which motion in one direction is chiral. We offer a general analysis of conduction in the latter by combining sum rule and renormalization group arguments, and find that when interlayer tunneling is marginal or irrelevant they are chiral semimetals that conduct only at T>0 or with disorder.

Determination of the orbital moment and crystal-field splitting in LaTiO3.

PubMed

Haverkort, M W; Hu, Z; Tanaka, A; Ghiringhelli, G; Roth, H; Cwik, M; Lorenz, T; Schüssler-Langeheine, C; Streltsov, S V; Mylnikova, A S; Anisimov, V I; de Nadai, C; Brookes, N B; Hsieh, H H; Lin, H-J; Chen, C T; Mizokawa, T; Taguchi, Y; Tokura, Y; Khomskii, D I; Tjeng, L H

2005-02-11

Utilizing a sum rule in a spin-resolved photoelectron spectroscopic experiment with circularly polarized light, we show that the orbital moment in LaTiO3 is strongly reduced from its ionic value, both below and above the Ne el temperature. Using Ti L2,3 x-ray absorption spectroscopy as a local probe, we found that the crystal-field splitting in the t2g subshell is about 0.12-0.30 eV. This large splitting does not facilitate the formation of an orbital liquid.

Exact Mass-Coupling Relation for the Homogeneous Sine-Gordon Model.

PubMed

Bajnok, Zoltán; Balog, János; Ito, Katsushi; Satoh, Yuji; Tóth, Gábor Zsolt

2016-05-06

We derive the exact mass-coupling relation of the simplest multiscale quantum integrable model, i.e., the homogeneous sine-Gordon model with two mass scales. The relation is obtained by comparing the perturbed conformal field theory description of the model valid at short distances to the large distance bootstrap description based on the model's integrability. In particular, we find a differential equation for the relation by constructing conserved tensor currents, which satisfy a generalization of the Θ sum rule Ward identity. The mass-coupling relation is written in terms of hypergeometric functions.

An Assessment of the Impact of the Contract Disputes Act of 1978 on U.S. Army Corps of Engineers’ Construction Contracts.

DTIC Science & Technology

1981-03-01

paid from the date the Contracting Officer accepts the claim until payment thereof. Simple interest will be paid as computed at the rate established by...were of quantum (e.g., involved monetary decisions). If money is part of the decision, the Board will often rule in favor of one party based on the... quantum is in issue the exact amount had to be stated. This sum would then have to be certified if it exceeded $50,000. Althoug ’ the legislative

Isoscalar giant resonances in Ca48

NASA Astrophysics Data System (ADS)

Lui, Y.-W.; Youngblood, D. H.; Shlomo, S.; Chen, X.; Tokimoto, Y.; Krishichayan; Anders, M.; Button, J.

2011-04-01

The giant resonance region from 9.5 MeV < Ex < 40 MeV in Ca48 has been studied with inelastic scattering of 240-MeV α particles at small angles, including 0°. 95-15+11% of E0 energy-weighted sum rule (EWSR), 83-16+10% of E2 EWSR, and 137 ± 20% of E1 EWSR were located below Ex=40 MeV. A comparison of the experimental data with calculated results for the isoscalar giant monopole resonance, obtained within the mean-field-based random-phase approximation, is also given.