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Sample records for generated hidden charm

  1. Dynamically generated N* and {Lambda}* resonances in the hidden charm sector around 4.3 GeV

    SciTech Connect

    Wu Jiajun; Molina, R.; Oset, E.; Zou, B. S.

    2011-07-15

    The interactions of D-bar{Sigma}{sub c}-D-bar{Lambda}{sub c}, D-bar*{Sigma}{sub c}-D-bar*{Lambda}{sub c}, and related strangeness channels, are studied within the framework of the coupled-channel unitary approach with the local hidden gauge formalism. A series of meson-baryon dynamically generated relatively narrow N* and {Lambda}* resonances are predicted around 4.3 GeV in the hidden charm sector. We make estimates of production cross sections of these predicted resonances in p-barp collisions for the experiment of antiproton annihilation at Darmstadt (PANDA) at the forthcoming GSI Facility for Antiproton and Ion Research (FAIR) facility.

  2. Prediction of narrow N* and {Lambda}* with hidden charm

    SciTech Connect

    Wu Jiajun; Molina, R.; Oset, E.; Zou, B. S.

    2011-10-24

    The interaction between various charmed mesons and charmed baryons, such as D-bar{Sigma}{sub c}-D-bar{Lambda}{sub c}, D-bar*{Sigma}{sub c}-D-bar*{Lambda}{sub c}, and related strangeness channels, are studied within the framework of the coupled channel unitary approach with the local hidden gauge formalism. Six narrow N* and {Lambda}* resonances are dynamically generated with mass above 4 GeV and width smaller than 100 MeV. These predicted new resonances definitely cannot be accommodated by quark models with three constituent quarks. We make estimates of production cross sections of these predicted resonances in p-barp collisions for PANDA at the forthcoming FAIR facility.

  3. Prediction of Narrow N* and {Lambda}* Resonances with Hidden Charm above 4 GeV

    SciTech Connect

    Wu Jiajun; Molina, R.; Oset, E.; Zou, B. S.

    2010-12-03

    The interaction between various charmed mesons and charmed baryons is studied within the framework of the coupled-channel unitary approach with the local hidden gauge formalism. Several meson-baryon dynamically generated narrow N{sup *} and {Lambda}{sup *} resonances with hidden charm are predicted with mass above 4 GeV and width smaller than 100 MeV. The predicted new resonances definitely cannot be accommodated by quark models with three constituent quarks and can be looked for in the forthcoming PANDA/FAIR experiments.

  4. The hidden-charm pentaquark and tetraquark states

    NASA Astrophysics Data System (ADS)

    Chen, Hua-Xing; Chen, Wei; Liu, Xiang; Zhu, Shi-Lin

    2016-06-01

    In the past decade many charmonium-like states were observed experimentally. Especially those charged charmonium-like Zc states and bottomonium-like Zb states cannot be accommodated within the naive quark model. These charged Zc states are good candidates of either the hidden-charm tetraquark states or molecules composed of a pair of charmed mesons. Recently, the LHCb Collaboration discovered two hidden-charm pentaquark states, which are also beyond the quark model. In this work, we review the current experimental progress and investigate various theoretical interpretations of these candidates of the multiquark states. We list the puzzles and theoretical challenges of these models when confronted with the experimental data. We also discuss possible future measurements which may distinguish the theoretical schemes on the underlying structures of the hidden-charm multiquark states.

  5. Towards Exotic Hidden-Charm Pentaquarks in QCD.

    PubMed

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

    2015-10-23

    Inspired by P(c)(4380) and P(c)(4450) recently observed by LHCb, a QCD sum rule investigation is performed, by which they can be identified as exotic hidden-charm pentaquarks composed of an anticharmed meson and a charmed baryon. Our results suggest that P(c)(4380) and P(c)(4450) have quantum numbers J(P)=3/2(-) and 5/2(+), respectively. Furthermore, two extra hidden-charm pentaqurks with configurations D̅Σ(c)(*) and D̅(*)Σ(c)(*) are predicted, which have spin-parity quantum numbers J(P)=3/2(-) and J(P)=5/2(+), respectively. As an important extension, the mass predictions of hidden-bottom pentaquarks are also given. Searches for these partners of P(c)(4380) and P(c)(4450) are especially accessible at future experiments like LHCb and BelleII. PMID:26551105

  6. Penta-Quark States with Strangeness, Hidden Charm and Beauty

    NASA Astrophysics Data System (ADS)

    Wu, Jia-Jun; Zou, Bing-Song

    The classical quenched quark models with three constituent quarks provide a good description for the baryon spatial ground states, but fail to reproduce the spectrum of baryon excited states. More and more evidences suggest that unquenched effects with multi-quark dynamics are necessary ingredients to solve the problem. Several new hyperon resonances reported recently could fit in the picture of penta-quark states. Based on this picture, some new hyperon excited states were predicted to exist; meanwhile with extension from strangeness to charm and beauty, super-heavy narrow N* and Λ* resonances with hidden charm or beauty were predicted to be around 4.3 and 11 GeV, respectively. Recently, two of such N* with hidden charm might have been observed by the LHCb experiment. More of those states are expected to be observed in near future. This opens a new window in order to study hadronic dynamics for the multi-quark states.

  7. Open and hidden charm muoproduction. [209 GeV

    SciTech Connect

    Clark, A.R.; Johnson, K.J.; Kerth, L.T.

    1980-09-01

    New results are presented on open and hidden charm and bottom production by 209-GeV muons interacting in a magnetized steel calorimeter. The upper limit on the production of T states by muons is sigma(..mu..N ..-->.. ..mu..UPSILONX)B(UPSILON ..-->.. ..mu mu..) < 22 x 10/sup -39/ cm/sup 2/ (90% confidence level). The distributions of elastically produced psi's are consistent with s-channel helicity conservation (SCHC) and disagree with psi dominance. From analysis of dimuon final states the cross section for diffractive charm muoproduction is 6.9/sub -1.4/sup +1.9/ nb. The structure function F/sub 2/(c anti c) for diffractive charmed-quark pair production is presented. 5 figures, 2 tables.

  8. Diffusion of hidden charm mesons in hadronic medium

    NASA Astrophysics Data System (ADS)

    Mitra, Sukanya; Ghosh, Sabyasachi; Das, Santosh K.; Sarkar, Sourav; Alam, Jan-e.

    2016-07-01

    The drag and diffusion coefficients of a hot hadronic medium have been evaluated by using hidden charm mesons as probes. The scattering amplitudes required for the evaluation of these coefficients are calculated using an effective theory and scattering lengths obtained from lattice QCD calculations. It is found that although the magnitude of the transport coefficients are small their temperature variation is strong. The insignificant momentum diffusion of J / ψ in the hadronic medium keeps their momentum distribution largely unaltered. Therefore, the task of characterization of quark gluon plasma by using the observed suppression of J / ψ at high momentum will be comparatively easier.

  9. Radiative decays of dynamically generated charmed baryons

    SciTech Connect

    Gamermann, D.; Jimenez-Tejero, C. E.; Ramos, A.

    2011-04-01

    In this work we study the radiative decay of dynamically generated J{sup P}=(1{sup -}/2) charm baryons into the ground state J{sup P}=(1{sup +}/2) baryons. Since different theoretical interpretations of these baryonic resonances and, in particular, of the {Lambda}{sub c}(2595), give different predictions, a precise experimental measurement of these decays would be an important step for understanding their nature.

  10. Formation of hidden-charm pentaquarks in photon-nucleon collisions

    DOE PAGESBeta

    Kubarovsky, Valery P.; Voloshin, M. B.

    2015-08-01

    The cross section for formation in γ + ρ collisions of the recently found hidden-charm pentaquark states Ρc(4380) and Ρc(4450) is discussed and estimated. The studies of these resonances in photon beam experiments can be complementary to those in the LHCb experiment setting, and may be more advantageous for measurement of their additional decay channels. It is pointed out that both the relative importance of such decays and the yield of the resonances in the γ + ρ collisions are sensitive to the internal dynamics of the pentaquarks and can resolve between theoretical models. Specific numerical estimates are discussed withinmore » a simple ‘baryocharmonium’ model, where the the observed Ρc resonances are composites of J/ψ and excited nucleon states with the quantum numbers of Ν(1440) and Ν(1520).« less

  11. Formation of hidden-charm pentaquarks in photon-nucleon collisions

    SciTech Connect

    Kubarovsky, Valery P.; Voloshin, M. B.

    2015-08-01

    The cross section for formation in γ + ρ collisions of the recently found hidden-charm pentaquark states Ρc(4380) and Ρc(4450) is discussed and estimated. The studies of these resonances in photon beam experiments can be complementary to those in the LHCb experiment setting, and may be more advantageous for measurement of their additional decay channels. It is pointed out that both the relative importance of such decays and the yield of the resonances in the γ + ρ collisions are sensitive to the internal dynamics of the pentaquarks and can resolve between theoretical models. Specific numerical estimates are discussed within a simple ‘baryocharmonium’ model, where the the observed Ρc resonances are composites of J/ψ and excited nucleon states with the quantum numbers of Ν(1440) and Ν(1520).

  12. The Λb → J/ψK- p reaction: Λ(1405) and hidden charm pentaquark formation

    NASA Astrophysics Data System (ADS)

    Oset, Eulogio; Roca, Luis; Mai, Maxim; Nieves, Juan

    2016-05-01

    In this talk we present an approach to the Λb → J/ψK- p reaction, where we look at the invariant mass of K- p and also πΣ, with a view to determine the shape and production rate of the Λ(1405) resonance. We compare the results obtained with the analysis of the same reaction, made a posteriori by the LHCb collaboration, in which two pentaquark states were claimed. At the same time we show the results of another work, prompted by the findings of the LHCb collaboration, where we show that there is consistency with the results obtained in the study of the Λb → J/ψK- p reaction with other results previously reported about a hidden charm baryon state.

  13. Looking for a hidden-charm pentaquark state with strangeness S =-1 from Ξb- decay into J /ψ K-Λ

    NASA Astrophysics Data System (ADS)

    Chen, Hua-Xing; Geng, Li-Sheng; Liang, Wei-Hong; Oset, Eulogio; Wang, En; Xie, Ju-Jun

    2016-06-01

    Assuming that the recently observed hidden-charm pentaquark state, Pc(4450 ) , is of molecular nature as predicted in the unitary approach, we propose to study the decay of Ξb-→J /ψ K-Λ to search for the strangeness counterpart of the Pc(4450 ) . There are three ingredients in the decay mechanism: the weak decay mechanism, the hadronization mechanism, and the final state interactions in the meson-baryon system of strangeness S =-2 and isospin I =1 /2 and of the J /ψ Λ . All these have been tested extensively. As a result, we provide a genuine prediction of the invariant mass distributions where a strangeness hidden-charm pentaquark state, the counterpart of the Pc(4450 ) , can be clearly seen. The decay rate is estimated to be of similar magnitude as the Λb0→J /ψ K-p measured by the LHCb Collaboration.

  14. Prediction of isoscalar charmoniumlike structures in the hidden-charm di-eta decays of higher charmonia

    NASA Astrophysics Data System (ADS)

    Chen, Dian-Yong; Liu, Xiang; Matsuki, Takayuki

    2015-01-01

    Considering the situation that a single chiral particle, η is initially emitted, we study the hidden-charm di-eta decays of the charmoniumlike state Y(4660) and the predicted charmonium \\psi (4790), i.e., Y(4660)/\\psi (4790)\\to J/\\psi η η through the inetermediates η [{{D}(*)}{{\\bar{D}}(*)}] and/or η [Ds+(*)Ds-(*)], and answer the important question of whether there exist isoscalar charmoniumlike structures in the {{D}(*)}{{\\bar{D}}(*)} and/or Ds+(*)Ds-(*) channels. Our results predict that there will be enhancement structures near D{{\\bar{D}}*}, {{D}*}{{\\bar{D}}*} and {{D}s}\\bar{D}s* thresholds for Y(4660) and near {{D}*}{{\\bar{D}}*}, {{D}s}\\bar{D}s* and Ds*\\bar{D}s* thresholds for \\psi (4790) in the {{M}max }(J/\\psi η ) distributions of Y(4660)/\\psi (4790)\\to η η J/\\psi , respectively. These peaks are accessible in future experiments, especially BESIII, Belle, BaBar, and the forthcoming BelleII.

  15. Natural movement generation using hidden Markov models and principal components.

    PubMed

    Kwon, Junghyun; Park, Frank C

    2008-10-01

    Recent studies have shown that the perception of natural movements-in the sense of being "humanlike"-depends on both joint and task space characteristics of the movement. This paper proposes a movement generation framework that merges two established techniques from gesture recognition and motion generation-hidden Markov models (HMMs) and principal components-into an efficient and reliable means of generating natural movements, which uniformly considers joint and task space characteristics. Given human motion data that are classified into several movement categories, for each category, the principal components extracted from the joint trajectories are used as basis elements. An HMM is, in turn, designed and trained for each movement class using the human task space motion data. Natural movements are generated as the optimal linear combination of principal components, which yields the highest probability for the trained HMM. Experimental case studies with a prototype humanoid robot demonstrate the various advantages of our proposed framework. PMID:18784005

  16. In-medium decay widths of hidden and open charm vector mesons in a field theoretic model for composite hadrons

    NASA Astrophysics Data System (ADS)

    Mishra, Amruta; Misra, S. P.; Greiner, W.

    2015-07-01

    We calculate the decay widths of the charmonium states, J/ψ, ψ(3686) and ψ(3770), to D\\bar {D} pairs, as well as the decay width of D* → Dπ, in isospin asymmetric strange hadronic matter, using a field theoretical model for composite hadrons with quark constituents. For this purpose, we use the quark-antiquark pair creation term of the free Dirac Hamiltonian written in terms of the constituent quark field operators, and use explicit charmonium, D, \\bar {D}, D* and π states to evaluate the matrix elements for the charmonium as well as D* decay amplitudes. The medium modifications of the partial decay widths of charmonium to D\\bar {D} pair, arising from the mass modifications of the D(\\bar {D}) and the charmonium states calculated in a chiral effective model, are also included. The results of the present investigations are then compared with the decay widths computed earlier, in a model using light quark pair creation in 3P0 state. As in 3P0 model, the decay amplitude in the present model is multiplied with a strength parameter for the light quark pair creation, which is fitted from the observed vacuum decay width. The effects of the isospin asymmetry, the strangeness fraction of the hadronic matter on the masses of the charmonium states and D(\\bar {D}) mesons and hence on the decay widths, have also been studied. The isospin asymmetry effect is observed to be dominant for high densities, leading to appreciable difference in the decay channels of the charmonium to D+ D- and D0 \\bar {D0} pairs. The decay width of D* → Dπ in the hadronic matter has also been calculated within the composite quark model in the present work, accounting for the medium modifications of the D and D* masses. The density modifications of the charmonium states and D(D*) mesons, which are observed to be appreciable at high densities, will be of relevance in the compressed baryonic matter (CBM) experiments at the future facility of FAIR, GSI, where charmed hadrons will be produced

  17. Charm Factories: Present and Future

    NASA Astrophysics Data System (ADS)

    Zweber, Peter

    2009-12-01

    The next generation tau-charm factory, the third Beijing Electron Spectrometer (BESIII) at the new Beijing Electron Positron Collider (BEPCII), has begun data collection. I discuss the flavor physics reach of the BESIII charm program and conclude with a discussion on future proposed tau-charm facilities.

  18. Next Generation Sequencing Reveals the Hidden Diversity of Zooplankton Assemblages

    PubMed Central

    Harmer, Rachel A.; Somerfield, Paul J.; Atkinson, Angus

    2013-01-01

    Background Zooplankton play an important role in our oceans, in biogeochemical cycling and providing a food source for commercially important fish larvae. However, difficulties in correctly identifying zooplankton hinder our understanding of their roles in marine ecosystem functioning, and can prevent detection of long term changes in their community structure. The advent of massively parallel next generation sequencing technology allows DNA sequence data to be recovered directly from whole community samples. Here we assess the ability of such sequencing to quantify richness and diversity of a mixed zooplankton assemblage from a productive time series site in the Western English Channel. Methodology/Principle Findings Plankton net hauls (200 µm) were taken at the Western Channel Observatory station L4 in September 2010 and January 2011. These samples were analysed by microscopy and metagenetic analysis of the 18S nuclear small subunit ribosomal RNA gene using the 454 pyrosequencing platform. Following quality control a total of 419,041 sequences were obtained for all samples. The sequences clustered into 205 operational taxonomic units using a 97% similarity cut-off. Allocation of taxonomy by comparison with the National Centre for Biotechnology Information database identified 135 OTUs to species level, 11 to genus level and 1 to order, <2.5% of sequences were classified as unknowns. By comparison a skilled microscopic analyst was able to routinely enumerate only 58 taxonomic groups. Conclusions Metagenetics reveals a previously hidden taxonomic richness, especially for Copepoda and hard-to-identify meroplankton such as Bivalvia, Gastropoda and Polychaeta. It also reveals rare species and parasites. We conclude that Next Generation Sequencing of 18S amplicons is a powerful tool for elucidating the true diversity and species richness of zooplankton communities. While this approach allows for broad diversity assessments of plankton it may become increasingly

  19. Strangeness and charm in nuclear matter

    NASA Astrophysics Data System (ADS)

    Tolos, Laura; Cabrera, Daniel; Garcia-Recio, Carmen; Molina, Raquel; Nieves, Juan; Oset, Eulogio; Ramos, Angels; Romanets, Olena; Salcedo, Lorenzo Luis

    2013-09-01

    The properties of strange (K, Kbar and K) and open-charm (D, Dbar and D*) mesons in dense matter are studied using a unitary approach in coupled channels for meson-baryon scattering. In the strangeness sector, the interaction with nucleons always comes through vector-meson exchange, which is evaluated by chiral and hidden gauge Lagrangians. For the interaction of charmed mesons with nucleons we extend the SU(3) Weinberg-Tomozawa Lagrangian to incorporate spin-flavor symmetry and implement a suitable flavor symmetry breaking. The in-medium solution for the scattering amplitude accounts for Pauli blocking effects and meson self-energies. On one hand, we obtain the K, Kbar and K spectral functions in the nuclear medium and study their behaviour at finite density, temperature and momentum. We also make an estimate of the transparency ratio of the γA→K+KA‧ reaction, which we propose as a tool to detect in-medium modifications of the K meson. On the other hand, in the charm sector, several resonances with negative parity are generated dynamically by the s-wave interaction between pseudoscalar and vector meson multiplets with 1/2+ and 3/2+ baryons. The properties of these states in matter are analyzed and their influence on the open-charm meson spectral functions is studied. We finally discuss the possible formation of D-mesic nuclei at FAIR energies.

  20. Charm and Charm Spectroscopy

    SciTech Connect

    Santoro, Valentina; /Ferrara U.

    2011-11-23

    Recent developements in D mixing physics and charm spectroscopy will be discussed. Focus will be on the BaBar experimental results for the D mixing: first evidence of the D{sup 0}-mixing (hadronic D{sup 0} decays), lifetime difference and time-dependent Dalitz plot analysis of D{sup 0} {yields} K{sup +}{pi}{sup -}{pi}{sup 0}. Then, recent results on charm spectroscopy will be presented with particular focus on the new Ds states that have been discovered in the last few years. Some of these states were not expected theoretically: their masses, widths, quantum numbers, and decay modes do not fit the existing spectroscopic classication, which is based mostly on potential model calculations.

  1. Phenomenology of nonperturbative charm in the nucleon

    DOE PAGESBeta

    Hobbs, T. J.; Londergan, J. T.; Melnitchouk, W.

    2014-04-02

    We perform a comprehensive analysis of the role of nonperturbative (or intrinsic) charm in the nucleon, generated through Fock state expansions of the nucleon wave function involving five-quark virtual states represented by charmed mesons and baryons. We consider contributions from a variety of charmed meson-baryon states and find surprisingly dominant effects from the D¯*0 Λc+ configuration. We pay particular attention to the existence and persistence of high-x structure for intrinsic charm, and the x dependence of the c-c¯ asymmetry predicted in meson-baryon models. We discuss how studies of charmed baryons and mesons in hadronic reactions can be used to constrainmore » models, and outline future measurements that could further illuminate the intrinsic charm component of the nucleon.« less

  2. Phenomenology of nonperturbative charm in the nucleon

    SciTech Connect

    Hobbs, T. J.; Londergan, J. T.; Melnitchouk, W.

    2014-04-02

    We perform a comprehensive analysis of the role of nonperturbative (or intrinsic) charm in the nucleon, generated through Fock state expansions of the nucleon wave function involving five-quark virtual states represented by charmed mesons and baryons. We consider contributions from a variety of charmed meson-baryon states and find surprisingly dominant effects from the D¯*0 Λc+ configuration. We pay particular attention to the existence and persistence of high-x structure for intrinsic charm, and the x dependence of the c-c¯ asymmetry predicted in meson-baryon models. We discuss how studies of charmed baryons and mesons in hadronic reactions can be used to constrain models, and outline future measurements that could further illuminate the intrinsic charm component of the nucleon.

  3. Spectroscopy of charmed baryons

    SciTech Connect

    Solovieva, E. I.

    2015-12-15

    Apresent-day classification of charmed baryons is presented, a quark model for ground states is briefly described, and the energy levels of excited states are analyzed. In addition, a survey of experimentally observed states of charmed baryons is given.

  4. Hidden Brønsted acid catalysis: pathways of accidental or deliberate generation of triflic acid from metal triflates.

    PubMed

    Dang, Tuan Thanh; Boeck, Florian; Hintermann, Lukas

    2011-11-18

    The generation of a hidden Brønsted acid as a true catalytic species in hydroalkoxylation reactions from metal precatalysts has been clarified in case studies. The mechanism of triflic acid (CF(3)SO(3)H or HOTf) generation starting either from AgOTf in 1,2-dichloroethane (DCE) or from a Cp*RuCl(2)/AgOTf/phosphane combination in toluene has been elucidated. The deliberate and controlled generation of HOTf from AgOTf and cocatalytic amounts of tert-butyl chloride in the cold or from AgOTf in DCE at elevated temperatures results in a hidden Brønsted acid catalyst useful for mechanistic control experiments or for synthetic applications. PMID:22010906

  5. Doubly charmful baryonic B decays

    SciTech Connect

    Cheng, H.-Y.; Chua, C.-K.; Tsai, S.-Y.

    2006-04-01

    There are two apparent puzzles connected with the two-body and three-body doubly charmed baryonic B decays. First, earlier calculations based on QCD sum rules or the diquark model predict B(B{sup 0}{yields}{xi}{sub c}{sup +}{lambda}{sub c}{sup -}){approx_equal}B(B{sup 0}{yields}B{sub c}N), while experimentally the former has a rate 2 orders of magnitude larger than the latter. Second, a naive estimate of the branching ratio O(10{sup -9}) for the color-suppressed three-body decay B{yields}{lambda}{sub c}{sup +}{lambda}{sub c}{sup -}K, which is highly suppressed by phase space, is too small by 5 to 6 orders of magnitude compared to the experiment. We show that the great suppression for the {lambda}{sub c}{sup +}{lambda}{sub c}{sup -}K production can be alleviated provided that there exists a narrow hidden charm bound state with a mass near the {lambda}{sub c}{lambda}{sub c} threshold. This new state that couples strongly to the charmed baryon pair can be searched for in B decays and in pp collisions by studying the mass spectrum of D{sup (*)}D{sup (*)} or {lambda}{sub c}{lambda}{sub c}. The doubly charmful decay B{yields}{xi}{sub c}{lambda}{sub c} has a configuration more favorable than the singly charmful one such as B{sup 0}{yields}{lambda}{sub c}p since no hard gluon is needed to produce the energetic {xi}{sub c}{lambda}{sub c} pair in the former decay, while two hard gluons are needed for the latter process. Assuming that a soft qq quark pair is produced through the {sigma} and {pi} meson exchanges in the configuration for B{yields}{xi}{sub c}{lambda}{sub c}, it is found that its branching ratio is of order 10{sup -3}, in agreement with the experiment.

  6. Charm Baryon Spectroscopy

    NASA Astrophysics Data System (ADS)

    Chistov, R.

    2016-02-01

    B-factories Belle and BaBar during its operation made not only measurements connected with B-meson decays but also numerous observation and measurements in charm physics. In particular, their results on charm baryon decays and spectroscopy have enlarged and enriched the current picture of heavy flavour hadrons. In this talk we overview current status of charm baryons and their excited states.

  7. Charming Mesons with Baryons and Nuclei

    NASA Astrophysics Data System (ADS)

    Tolos, Laura

    2013-11-01

    The properties of charmed mesons in nuclear matter and nuclei are reviewed. Different frameworks are discussed paying a special attention to unitarized coupled-channel approaches which incorporate heavy-quark spin symmetry. Several charmed baryon states with negative parity are generated dynamically by the s-wave interaction between pseudoscalar and vector meson multiplets with 1/2+ and 3/2+ baryons. These states are compared to experimental data. Moreover, the properties of open-charm mesons in matter are analyzed. The in-medium solution accounts for Pauli blocking effects, and for the meson self-energies in a self-consistent manner. The behavior in the nuclear medium of the rich spectrum of dynamically-generated baryon states is studied as well as their influence in the self-energy and, hence, the spectral function of open charm. The possible experimental signatures of the in-medium properties of open charm are finally addressed, such as the formation of charmed nuclei, in connection with the future FAIR facility.

  8. Physics of the Charm Quark

    SciTech Connect

    Carrillo Moreno, Salvador; Vazquez Valencia, Elsa Fabiola

    2006-09-25

    This is a brief summary about the development of the charm quark physics in the area of experimental physics. The summary is centered in what is done by mexican physicists, particularly in the E791 and the FOCUS Experiment at FERMILAB. FOCUS (or E831) was designed to detect states of matter combining one or more charm quarks with light quarks (strange, up, down). The experiment created 10 times as many such particles as in previous experiments and investigated several topics on charm physics including high precision studies of charm semileptonic decays, studies of hadronic charm decays (branching ratios and Daltiz analyses), lifetime measurements of all charm particles, searches for mixing, CP/CPT violation, rare and forbidden decays, spectroscopy of excited charm mesons and baryons, charm production asymmetry measurements, light quark diffractive studies, QCD studies using charm pair events and searches for and upper limits on: charm pentaquarks, double charm baryons, DSJ(2632)

  9. Discovery of naked charm particles and lifetime differences among charm species using nuclear emulsion techniques innovated in Japan

    PubMed Central

    NIU, Kiyoshi

    2008-01-01

    This is a historical review of the discovery of naked charm particles and lifetime differences among charm species. These discoveries in the field of cosmic-ray physics were made by the innovation of nuclear emulsion techniques in Japan. A pair of naked charm particles was discovered in 1971 in a cosmic-ray interaction, three years prior to the discovery of the hidden charm particle, J/Ψ, in western countries. Lifetime differences between charged and neutral charm particles were pointed out in 1975, which were later re-confirmed by the collaborative Experiment E531 at Fermilab. Japanese physicists led by K.Niu made essential contributions to it with improved emulsion techniques, complemented by electronic detectors. This review also discusses the discovery of artificially produced naked charm particles by us in an accelerator experiment at Fermilab in 1975 and of multiple-pair productions of charm particles in a single interaction in 1987 by the collaborative Experiment WA75 at CERN. PMID:18941283

  10. Baryons with open beauty dynamically generated from meson-baryon interaction in the extended local hidden gauge approach

    NASA Astrophysics Data System (ADS)

    Liang, Wei-Hong; Xiao, C. W.; Oset, E.

    2016-05-01

    In this talk we review the results about the interaction of B ¯N , B ¯Δ, B ¯*N and B ¯*Δ states with beauty B = 1, together with their coupled channels, using the extended local hidden gauge approach. The Λb(5912) and Λb(5920) observed in the experiment are dynamically generated from the meson-baryon interaction, and they couple mostly to B ¯*N , which are degenerate with the Weinberg-Tomozawa interaction. In addition, three more states with I = 0 and eight more states with I = 1 are predicted.

  11. Charm photoproduction dynamics

    SciTech Connect

    Garbincius, P.H.

    1995-03-01

    Photoproduction of open charm is reviewed, both as a tool for studying the properties of charm particles such as spectroscopy, decays, and lifetimes, and as a testing ground for theoretical calculations of production dynamics. Many characteristics of charm photoproduction are described in terms of the leading order (LO) {alpha}{sub EM}{alpha}{sub S} Photon-Gluon Fusion (PGF) model. The next-to-leading order (NLO) corrections of strength {alpha}{sub EM}{alpha}{sub S}{sup 2} due to radiation of additional gluons are then added. The sensitivities of the NLO calculations on the mass of the charm quark, m{sub c}, and on the choice of the gluon structure function of the nucleon are illustrated for the energy dependence of the cross section for charm photoproduction. These are compared with fixed target data and new HERA data. The single charm particle inclusive distributions in x{sub f} and p{sub {perpendicular}}{sup 2}, along with {sigma}({gamma}N {yields} c{anti c}X) give good estimates of m{sub c} and n{sub g}, the shape parameter for the gluon distribution within the nucleon. As in hadroproduction, some disagreements between prediction and observation begin to appear in trying to simultaneously match the distributions in both p{sub {perpendicular}}{sup 2} for single charm particles and in the {Delta}{Phi} acoplanarity angle between pairs of charm particles. These can be partially remedied by modifying the fragmentation function for c-quarks into charm particles, and by including extra k{sub {perpendicular}}{sup 2} transverse smearing of the gluon distributions within the target nucleon. Initial studies of the relative production between charm particles and anti-particles indicate disagreement with the predictions of the independent string fragmentation model.

  12. Discovery of Charm

    DOE R&D Accomplishments Database

    Goldhaber, G.

    1984-11-01

    In my talk I will cover the period 1973 to 1976 which saw the discoveries of the J/psi and psi' resonances and most of the Psion spectroscopy, the tau lepton and the D0030099,D0015599 charmed meson doublet. Occasionally I will refer briefly to more recent results. Since this conference is on the history of the weak-interactions I will deal primarily with the properties of naked charm and in particular the weakly decaying doublet of charmed mesons. Most of the discoveries I will mention were made with the SLAC-LBL Magnetic Detector or MARK I which we operated at SPEAR from 1973 to 1976.

  13. Charmed Hadron Interactions

    SciTech Connect

    Liu, Liuming

    2009-07-01

    We calculate the scattering lengths of the scattering processes where one or both hadrons contain charm quarks in full lattice QCD. We use relativistic Fermilab formulation for the charm quark. For the light quark, we use domain-wall fermions in the valence sector and improved Kogut- Susskind sea quarks. In J = Psi - N and D - K channels, we observe attractive interactions. In D - D* channel, the sign of the scattering length changes, which suggests a bound state.

  14. Charm production in DPMJET

    SciTech Connect

    Berghaus, P; Montaruli, T; Ranft, J E-mail: montaruli@ba.infn.it

    2008-06-15

    In this work, charm production in the DPMJET hadronic jet simulation is compared to experimental data. Since the major application of DPMJET is the simulation of cosmic-ray-induced air showers, the version of the code integrated in the CORSIKA simulation package has been used for the comparison. Wherever necessary, adjustments have been made to improve agreement between simulation and data. With the availability of new muon/neutrino detectors that combine a large fiducial volume with large amounts of shielding, investigation of prompt muons and neutrinos from cosmic ray interactions will be feasible for the first time. Furthermore, above {approx}>100 TeV charmed particle decay becomes the dominant background for diffuse extraterrestrial neutrino flux searches. A reliable method to simulate charm production in high-energy proton-nucleon interactions is therefore required.

  15. Charmed Bottom Baryon Spectroscopy

    SciTech Connect

    Brown, Zachary S; Detmold, William; Meinel, Stefan; Orginos, Kostas

    2014-11-01

    The spectrum of doubly and triply heavy baryons remains experimentally unexplored to a large extent. Although the detection of such heavy particle states may lie beyond the reach of exper- iments for some time, it is interesting compute this spectrum from QCD and compare results between lattice calculations and continuum theoretical models. Several lattice calculations ex- ist for both doubly and triply charmed as well as doubly and triply bottom baryons. Here, we present preliminary results from the first lattice calculation of doubly and triply heavy baryons including both charm and bottom quarks. We use domain wall fermions for 2+1 flavors (up down and strange) of sea and valence quarks, a relativistic heavy quark action for the charm quarks, and non-relativistic QCD for the heavier bottom quarks. We present preliminary results for the ground state spectrum.

  16. Second harmonic generation microscopy reveals hidden polar organization in fluoride doped MIL-53(Fe).

    PubMed

    Markey, Karen; Putzeys, Tristan; Horcajada, Patricia; Devic, Thomas; Guillou, Nathalie; Wübbenhorst, Michael; Cleuvenbergen, Stijn Van; Verbiest, Thierry; De Vos, Dirk E; van der Veen, Monique A

    2016-03-01

    Polar metal-organic frameworks have potential applications as functional non-linear optical, piezoelectric, pyroelectric and ferroelectric materials. Using second harmonic generation microscopy we found that fluoride doping of the microporous iron(iii) terephthalate MOF MIL-53(Fe) induces a polar organization in its structure, which was not previously detected with XRD. The polar order is only observed when both fluoride and guest molecules are present, and may be related to a complex interplay between the adsorbates and the framework, leading to a modification of the positioning of fluoride in the inorganic Fe-chains. Combined polarized second harmonic generation microscopy and scanning pyroelectric microscopy show that the polar axis is unidirectional and of the same sense over the whole crystal, extending up to 100 micrometers. This finding shows how MOF materials can be endowed with useful properties by doping MOFs with fluoride. PMID:26812223

  17. Spectroscopy of doubly charmed baryons

    SciTech Connect

    Vijande, J.; Valcarce, A.; Fernandez, F.; Garcilazo, H.

    2006-02-11

    We study the mass spectrum of baryons with two and three charmed quarks. For double charm baryons the spin splitting is found to be smaller than standard quark-model potential predictions. This splitting is not influenced either by the particular form of the confining potential or by the regularization taken for the contact term of the spin-spin potential. We consistently predict the spectra for triply charmed baryons.

  18. Charmed Bottom Baryon Spectroscopy

    SciTech Connect

    Zachary Brown, William Detmold, Stefan Meinel, Konstantinos Orginos

    2012-09-01

    The arena of doubly and triply heavy baryons remains experimentally unexplored to a large extent. This has led to a great deal of theoretical effort being put forth in the calculation of mass spectra in this sector. Although the detection of such heavy particle states may lie beyond the reach of experiments for some time, it is interesting to compare results between lattice QCD computations and continuum theoretical models. Several recent lattice QCD calculations exist for both doubly and triply charmed as well as doubly and triply bottom baryons. In this work we present preliminary results from the first lattice calculation of the mass spectrum of doubly and triply heavy baryons including both charm and bottom quarks. The wide range of quark masses in these systems require that the various flavors of quarks be treated with different lattice actions. We use domain wall fermions for 2+1 flavors (up down and strange) of sea and valence quarks, a relativistic heavy quark action for the charm quarks, and non-relativistic QCD for the heavier bottom quarks. The calculation of the ground state spectrum is presented and compared to recent models.

  19. Exotic Effects at the Charm Threshold and Other Novel Physics Topics at JLab-12 GeV

    SciTech Connect

    Brodsky, Stanley J.; /SLAC

    2012-05-03

    I briefly survey a number of novel hadron physics topics which can be investigated with the 12 GeV upgrade at J-Lab. The topics include new the formation of exotic heavy quark resonances accessible above the charm threshold, intrinsic charm and strangeness phenomena, the exclusive Sivers effect, hidden-color Fock states of nuclei, local two-photon interactions in deeply virtual Compton scattering, and non-universal antishadowing.

  20. The total charm cross section

    SciTech Connect

    Vogt, R

    2007-09-14

    We assess the theoretical uncertainties on the total charm cross section. We discuss the importance of the quark mass, the scale choice and the parton densities on the estimate of the uncertainty. We conclude that the uncertainty on the total charm cross section is difficult to quantify.

  1. Excited Charm States

    SciTech Connect

    Shukla, S.

    1994-12-31

    Characteristics of mass spectra and decays of orbitally excited charm mesons and baryons, expected on the basis of quark models and Heavy Quark Symmetry, are briefly described. The difficulties associated with measurements on these excited states are discussed. The accuracy and reliability of currently available experimental information is examined. The reasons, for the widely accepted spin-parity assignments to the observed excited mesons and baryons, are stated. Finally, the experimental data, with the accepted spin-parity assignments, is compared with expectations based on quark models and Heavy Quark Symmetry.

  2. Charmed baryon spectroscopy from CLEO at CESR

    SciTech Connect

    Alam, M. Sajjad

    1999-02-17

    Charmed baryon spectroscopy has been unfolding since the discovery of the first charmed baryon in 1975. The Cornell Electron Storage Ring (CESR) has now established itself as a charmed particle factory. In this report, we present results on charmed baryon production at CESR using the CLEO detector.

  3. Charm counting in b decays

    NASA Astrophysics Data System (ADS)

    Buskulic, D.; de Bonis, I.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Odier, P.; Pietrzyk, B.; Casado, M. P.; Chmeissani, M.; Crespo, J. M.; Delfino, M.; Efthymiopoulos, I.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Juste, A.; Martinez, M.; Orteu, S.; Padilla, C.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Teubert, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Girone, M.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Alemany, R.; Bazarko, A. O.; Bonvicini, G.; Bright-Thomas, P.; Cattaneo, M.; Cerutti, F.; Comas, P.; Coyle, P.; Drevermann, H.; Forty, R. W.; Frank, M.; Hagelberg, R.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Knobloch, J.; Lehraus, I.; Lutters, G.; Martin, E. B.; Mato, P.; Minten, A.; Miquel, R.; Mir, Ll. M.; Moneta, L.; Oest, T.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rensing, P.; Rizzo, G.; Rolandi, L.; Schlatter, D.; Schmelling, M.; Schmitt, M.; Schneider, O.; Tejessy, W.; Tomalin, I. R.; Venturi, A.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barrès, A.; Boyer, C.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.-M.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Zachariadou, K.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Rougé, A.; Rumpf, M.; Valassi, A.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Focardi, E.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Knowles, I. G.; Lynch, J. G.; O'Shea, V.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, F.; Thorn, S.; Turnbull, R. M.; Becker, U.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Schmidt, M.; Sommer, J.; Stenzel, H.; Tittel, K.; Werner, S.; Wunsch, M.; Abbaneo, D.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Stacey, A. M.; Williams, M. D.; Dissertori, G.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Sloan, T.; Williams, M. I.; Galla, A.; Giehl, I.; Greene, A. M.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Calvet, D.; Carr, J.; Diaconu, C.; Etienne, F.; Konstantinidis, N.; Payre, P.; Rousseau, D.; Talby, M.; Sadouki, A.; Thulasidas, M.; Trabelsi, K.; Aleppo, M.; Ragusa, F.; Bauer, C.; Berlich, R.; Blum, W.; Büscher, V.; Dietl, H.; Dydak, F.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; Denis, R. St.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Choi, Y.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Nikolic, I.; Park, H. J.; Schune, M.-H.; Simion, S.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Batignani, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; Dell'Orso, R.; Fantechi, R.; Ferrante, I.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciabà, A.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Vannini, C.; Verdini, P. G.; Blair, G. A.; Bryant, L. M.; Chambers, J. T.; Gao, Y.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Maley, P.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Johnson, R. P.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Boswell, R.; Brew, C. A. J.; Cartwright, S.; Combley, F.; Koksal, A.; Letho, M.; Newton, W. M.; Reeve, J.; Thompson, L. F.; Böhrer, A.; Brandt, S.; Cowan, G.; Grupen, C.; Minguet-Rodriguez, J.; Rivera, F.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; Della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Rothberg, J.; Wasserbaech, S.; Armstrong, S. R.; Elmer, P.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; González, S.; Grahl, J.; Greening, T. C.; Hayes, O. J.; Hu, H.; McNamara, P. A.; Nachtman, J. M.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, A. M.; Walsh, J.; Wu, Sau Lan; Wu, X.; Yamartino, J. M.; Zheng, M.; Zobernig, G.; Aleph Collaboration

    1996-02-01

    The inclusive production of charmed particles in Z → b overlineb decays has been measured from the yield of D0, D+, Ds+ and Λc+ decays in a sample of q overlineq events with high b purity collected with the ALEPH detector from 1992 to 1995. From these measurements, adding the charmonia production rate and an estimate of the charmed strange baryon contribution, the average number of charm quarks per b decay is determined to be nc = 1.230 ± 0.036 ± 0.038 ± 0.053, where the uncertainties are due to statistics, systematic effects and branching ratios, respectively.

  4. Nuclear dependence of charm production

    NASA Astrophysics Data System (ADS)

    Blanco-Covarrubias, A.; Engelfried, J.; Akgun, U.; Alkhazov, G.; Amaro-Reyes, J.; Atamantchouk, A. G.; Ayan, A. S.; Balatz, M. Y.; Bondar, N. F.; Cooper, P. S.; Dauwe, L. J.; Davidenko, G. V.; Dersch, U.; Dolgolenko, A. G.; Dzyubenko, G. B.; Edelstein, R.; Emediato, L.; Endler, A. M. F.; Eschrich, I.; Escobar, C. O.; Estrada, N.; Evdokimov, A. V.; Filimonov, I. S.; Flores-Castillo, A.; Garcia, F. G.; Golovtsov, V. L.; Gouffon, P.; Gülmez, E.; Iori, M.; Jun, S. Y.; Kaya, M.; Kilmer, J.; Kim, V. T.; Kochenda, L. M.; Konorov, I.; Kozhevnikov, A. P.; Krivshich, A. G.; Krüger, H.; Kubantsev, M. A.; Kubarovsky, V. P.; Kulyavtsev, A. I.; Kuropatkin, N. P.; Kurshetsov, V. F.; Kushnirenko, A.; Lach, J.; Landsberg, L. G.; Larin, I.; Leikin, E. M.; López-Hinojosa, G.; Lungov, T.; Maleev, V. P.; Mao, D.; Mathew, P.; Mattson, M.; Matveev, V.; McCliment, E.; Moinester, M. A.; Molchanov, V. V.; Morelos, A.; Nemitkin, A. V.; Neoustroev, P. V.; Newsom, C.; Nilov, A. P.; Nurushev, S. B.; Ocherashvili, A.; Onel, Y.; Ozkorucuklu, S.; Penzo, A.; Petrenko, S. V.; Procario, M.; Prutskoi, V. A.; Razmyslovich, B. V.; Rud, V. I.; Russ, J.; Sánchez-López, J. L.; Simon, J.; Sitnikov, A. I.; Smith, V. J.; Srivastava, M.; Steiner, V.; Stepanov, V.; Stutte, L.; Svoiski, M.; Terentyev, N. K.; Torres, I.; Uvarov, L. N.; Vasiliev, A. N.; Vavilov, D. V.; Vázquez-Jáuregui, E.; Verebryusov, V. S.; Victorov, V. A.; Vishnyakov, V. E.; Vorobyov, A. A.; Vorwalter, K.; You, J.; Zukanovich-Funchal, R.

    2009-12-01

    Using data taken by SELEX during the 1996-1997 fixed target run at Fermilab, we study the production of charmed hadrons on copper and carbon targets with Σ -, p, π -, and π + beams. Parametrizing the dependence of the inclusive production cross section on the atomic number A as A α , we determine α for D +, D 0, D {/s +}, D +(2010), Λ {/c +}, and their respective anti-particles, as a function of their transverse momentum p t and scaled longitudinal momentum x F . Within our statistics there is no dependence of α on x F for any charm species for the interval 0.1< x F <1.0. The average value of α for charm production by pion beams is α meson=0.850±0.028. This is somewhat larger than the corresponding average α baryon=0.755±0.016 for charm production by baryon beams ( Σ -, p).

  5. A critical assessment of hidden markov model sub-optimal sampling strategies applied to the generation of peptide 3D models.

    PubMed

    Lamiable, A; Thevenet, P; Tufféry, P

    2016-08-01

    Hidden Markov Model derived structural alphabets are a probabilistic framework in which the complete conformational space of a peptidic chain is described in terms of probability distributions that can be sampled to identify conformations of largest probabilities. Here, we assess how three strategies to sample sub-optimal conformations-Viterbi k-best, forward backtrack and a taboo sampling approach-can lead to the efficient generation of peptide conformations. We show that the diversity of sampling is essential to compensate biases introduced in the estimates of the probabilities, and we find that only the forward backtrack and a taboo sampling strategies can efficiently generate native or near-native models. Finally, we also find such approaches are as efficient as former protocols, while being one order of magnitude faster, opening the door to the large scale de novo modeling of peptides and mini-proteins. © 2016 Wiley Periodicals, Inc. PMID:27317417

  6. Hidden earthquakes

    SciTech Connect

    Stein, R.S.; Yeats, R.S.

    1989-06-01

    Seismologists generally look for earthquakes to happen along visible fault lines, e.g., the San Andreas fault. The authors maintain that another source of dangerous quakes has been overlooked: the release of stress along a fault that is hidden under a fold in the earth's crust. The paper describes the differences between an earthquake which occurs on a visible fault and one which occurs under an anticline and warns that Los Angeles greatest earthquake threat may come from a small quake originating under downtown Los Angeles, rather than a larger earthquake which occurs 50 miles away at the San Andreas fault.

  7. Charms of radiation research.

    SciTech Connect

    Inokuti, M.; Physics

    2005-01-01

    Most of my professional efforts over nearly five decades have been devoted to radiation research, that is, studies of the physical, chemical, and biological actions of high-energy radiation on matter. (By the term 'high-energy radiation' I mean here x rays, .GAMMA. rays, neutrons, and charged particles of high enough energies to produce ionization in matter. I exclude visible light, infrared waves, microwaves, and sound waves.) Charms of radiation research lie in its interdisciplinary character; although my training was in basic physics, the scope of my interest has gradually increased to cover many other areas, to my deep satisfaction. High-energy radiation is an important component of the universe, and of our environment. It often provides an effective avenue for characterizing matter and understanding its behavior. Near Earth's surface this radiation is normally present in exceptionally low quantity, and yet it plays a significant role in some atmospheric phenomena such as auroras, and also in the evolution of life. The recent advent of various devices for producing high-energy radiation has opened up the possibility of many applications, including medical and industrial uses. I have worked on some aspects of those uses. At every opportunity to address a broad audience I try to convey a sense of intellectual fun, together with some of the elements of the basic science involved. A goal of radiation education might be to make the word 'radiation' as common and familiar as words such as 'fire' and 'electricity' through increased usage.

  8. A Tau-Charm Factory at CEBAF

    SciTech Connect

    Seth, K.K.

    1994-04-01

    It is proposed that a Tau Charm Factory represents a natural extension of CEBAF into higher energy domains. The exciting nature of the physics of charm quarks and tau leptons is briefly reviewed and it is suggested that the concept of a linac-ring collider as a Tau Charm Factory at CEBAF should be seriously studied.

  9. Nuclear Filtering of Intrinsic Charm

    SciTech Connect

    Kopeliovich, B. Z.; Potashnikova, I. K.; Schmidt, Ivan

    2010-11-12

    Nuclei are transparent for a heavy intrinsic charm (IC) component of the beam hadrons, what leads to an enhanced nuclear dependence of open charm production at large Feynman x{sub F}. Indeed, such an effect is supported by data from the SELEX experiment published recently [1]. Our calculations reproduce well the data, providing strong support for the presence of IC in hadrons in amount less than 1%. Moreover, we performed an analysis of nuclear effects in J/{Psi} production and found at large x{sub F} a similar, albeit weaker effect, which does not contradict data.

  10. BCFtools/RoH: a hidden Markov model approach for detecting autozygosity from next-generation sequencing data

    PubMed Central

    Narasimhan, Vagheesh; Danecek, Petr; Scally, Aylwyn; Xue, Yali; Tyler-Smith, Chris; Durbin, Richard

    2016-01-01

    Summary: Runs of homozygosity (RoHs) are genomic stretches of a diploid genome that show identical alleles on both chromosomes. Longer RoHs are unlikely to have arisen by chance but are likely to denote autozygosity, whereby both copies of the genome descend from the same recent ancestor. Early tools to detect RoH used genotype array data, but substantially more information is available from sequencing data. Here, we present and evaluate BCFtools/RoH, an extension to the BCFtools software package, that detects regions of autozygosity in sequencing data, in particular exome data, using a hidden Markov model. By applying it to simulated data and real data from the 1000 Genomes Project we estimate its accuracy and show that it has higher sensitivity and specificity than existing methods under a range of sequencing error rates and levels of autozygosity. Availability and implementation: BCFtools/RoH and its associated binary/source files are freely available from https://github.com/samtools/BCFtools. Contact: vn2@sanger.ac.uk or pd3@sanger.ac.uk Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26826718

  11. Properties of excited charm and charm-strange mesons

    NASA Astrophysics Data System (ADS)

    Godfrey, Stephen; Moats, Kenneth

    2016-02-01

    We calculate the properties of excited charm and charm-strange mesons. We use the relativized quark model to calculate their masses and wave functions that are used to calculate radiative transition partial widths and the 3P0 quark-pair-creation model to calculate their strong decay widths. We use these results to make quark model spectroscopic assignments for recently observed charm and charm-strange mesons. In particular, we find that the properties of the DJ(2550 )0 and DJ*(2600 )0 are consistent with those of the 2 1S0 (c u ¯) and the 2 3S1 (c u ¯) states respectively, and the D1*(2760 )0, D3*(2760 )-,and DJ(2750 )0with those of the 1 3D1 (c u ¯), 1 3D3 (d c ¯), and 1 D2(c u ¯) states respectively. We tentatively identify the DJ*(3000 )0 as the 1 3F4 (c u ¯ ) and favor the DJ(3000 )0 to be the 3 1S0 (c u ¯ ) although we do not rule out the 1 F3 and 1 F3' assignment. For the recently observed charm-strange mesons we identify the Ds1 *(2709 )±,Ds1 *(2860 )-,andDs3 *(2860 )-as the 2 3S1 (c s ¯), 1 3D1 (s c ¯), and 1 3D3 (s c ¯) states respectively and suggest that the Ds J(3044 )± is most likely the Ds 1(2 P1' ) or Ds 1(2 P1) state although it might be the Ds2 *(2 3P2 ) with the D K final state too small to be observed with current statistics. Based on the predicted properties of excited states, that they do not have too large a total width and that they have a reasonable branching ratio to simple final states, we suggest states that should be able to be found in the near future. We expect that the tables of properties summarizing our results will be useful for interpreting future observations of charm and charm-strange mesons.

  12. Nuclear Dependence of Charm Production

    SciTech Connect

    Blanco-Covarrubias, A.; Engelfried, J.; Akgun, U.; Alkhazov, G.; Amaro-Reyes, J.; Atamantchouk, A.G.; Ayan, A.S.; Balatz, M.Y.; Bondar, N.F.; Cooper, P.S.; Dauwe, Loretta J.; /Michigan U., Flint /Moscow, ITEP

    2009-02-01

    With data taken by SELEX, which accumulated data during the 1996-1997 fixed target run at Fermilab, we study the production of charmed hadrons on copper and carbon targets with {Sigma}{sup -}, p, {pi}{sup -}, and {pi}{sup +} beams. Parameterizing the production cross section {infinity} A{sup {alpha}}, A being the atomic number, we determine {alpha} for D{sup +}, D{sup 0}, D{sub s}{sup +}, D{sup +}(2010), {Lambda}{sub c}{sup +}, and their respective anti-particles, as a function of their transverse momentum p{sub t} and scaled longitudinal momentum x{sub F}. Within our statistics there is no dependence of {alpha} on x{sub F} for any charm species for the interval 0.1 < x{sub F} < 1.0. The average value of {alpha} for charm production by pion beams is {alpha}{sub meson} = 0.850 {+-} 0.028. This is somewhat larger than the corresponding average {alpha}{sub baryon} = 0.755 {+-} 0.016 for charm production by baryon beams ({Sigma}{sup -}, p).

  13. New states above charm threshold

    SciTech Connect

    Eichten, Estia J.; Lane, Kenneth; Quigg, Chris; /Fermilab

    2005-11-01

    We revise and extend expectations for the properties of charmonium states that lie above charm threshold, in light of new experimental information. We refine the Cornell coupled-channel model for the coupling of c{bar c} levels to two-meson states, defining resonance masses and widths by pole positions in the complex energy plane, and suggest new targets for experiment.

  14. Theoretical understanding of charm decays

    SciTech Connect

    Bigi, I.I.

    1986-08-01

    A detailed description of charm decays has emerged. The various concepts involved are sketched. Although this description is quite successful in reproducing the data the chapter on heavy flavour decays is far from closed. Relevant questions like on th real strength of weak annihilation, Penguin operators, etc. are still unanswered. Important directions in future work, both on the experimental and theoretical side are identified.

  15. Suppressed Charmed B Decay

    SciTech Connect

    Snoek, Hella Leonie

    2009-06-02

    This thesis describes the measurement of the branching fractions of the suppressed charmed B0 → D*- a0+ decays and the non-resonant B0 → D*- ηπ+ decays in approximately 230 million Υ(4S) → B$\\bar{B}$ events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B0 → D*- a{sub 0}+ decays show large QCD model dependent uncertainties. Non-factorizing terms, in the naive factorization model, that can be calculated by QCD factorizing models have a large impact on the branching fraction of these decay modes. The predictions of the branching fractions are of the order of 10-6. The measurement of the branching fraction gives more insight into the theoretical models. In general a better understanding of QCD models will be necessary to conduct weak interaction physics at the next level. The presence of CP violation in electroweak interactions allows the differentiation between matter and antimatter in the laws of physics. In the Standard Model, CP violation is incorporated in the CKM matrix that describes the weak interaction between quarks. Relations amongst the CKM matrix elements are used to present the two relevant parameters as the apex of a triangle (Unitarity Triangle) in a complex plane. The over-constraining of the CKM triangle by experimental measurements is an important test of the Standard Model. At this moment no stringent direct measurements of the CKM angle γ, one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle γ can be performed using the decays of neutral B mesons. The B0 → D*- a0+ decay is sensitive to the angle γ and, in comparison to the current decays that are being employed, could significantly

  16. Hadron Physics at the Charm and Bottom Thresholds and Other Novel QCD Physics Topics at the NICA Accelerator Facility

    SciTech Connect

    Brodsky, Stanley J.; /SLAC

    2012-06-20

    The NICA collider project at the Joint Institute for Nuclear Research in Dubna will have the capability of colliding protons, polarized deuterons, and nuclei at an effective nucleon-nucleon center-of mass energy in the range {radical}s{sub NN} = 4 to 11 GeV. I briefly survey a number of novel hadron physics processes which can be investigated at the NICA collider. The topics include the formation of exotic heavy quark resonances near the charm and bottom thresholds, intrinsic strangeness, charm, and bottom phenomena, hidden-color degrees of freedom in nuclei, color transparency, single-spin asymmetries, the RHIC baryon anomaly, and non-universal antishadowing.

  17. Hidden symmetries and black holes

    NASA Astrophysics Data System (ADS)

    Frolov, Valeri P.

    2009-10-01

    The paper contains a brief review of recent results on hidden symmetries in higher dimensional black hole spacetimes. We show how the existence of a principal CKY tensor (that is a closed conformal Killing-Yano 2-form) allows one to generate a `tower' of Killing-Yano and Killing tensors responsible for hidden symmetries. These symmetries imply complete integrability of geodesic equations and the complete separation of variables in the Hamilton-Jacobi, Klein-Gordon, Dirac and gravitational perturbation equations in the general Kerr-NUT-(A)dS metrics. Equations of the parallel transport of frames along geodesics in these spacetimes are also integrable.

  18. Spectroscopy of charmed baryons from lattice QCD

    SciTech Connect

    Padmanath, M.; Edwards, Robert G.; Mathur, Nilmani; Peardon, Michael

    2015-01-01

    We present the ground and excited state spectra of singly, doubly and triply charmed baryons by using dynamical lattice QCD. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6) x O(3) symmetry. Various energy splittings between the extracted states, including splittings due to hyperfine as well as spin-orbit coupling, are considered and those are also compared against similar energy splittings at other quark masses.

  19. The hidden effects of child maltreatment in a war region: correlates of psychopathology in two generations living in Northern Uganda.

    PubMed

    Olema, David Kani; Catani, Claudia; Ertl, Verena; Saile, Regina; Neuner, Frank

    2014-02-01

    Adverse life experiences are a major risk factor for psychopathology. Studies from industrialized countries have consistently shown the detrimental effects of child maltreatment on the mental health of the victims. Research in war-affected populations, however, has mostly been restricted to the psychological damage caused by the war. Both war trauma and child maltreatment have rarely been studied simultaneously. In a comparative study of 2 generations living in severely war-affected regions in Northern Uganda, we determined the relationship between both trauma types and posttraumatic stress disorder (PTSD), anxiety, depression, and suicide ideation. A total of 100 adolescents, 50 with and 50 without a history of abduction by the rebel army with both their parents (100 mothers and 100 fathers) living in camps in northern Uganda were interviewed. The study showed that both generations were severely affected by war and child maltreatment. Both trauma types were independently correlated with psychological disorders in the adolescent group. Only child maltreatment, however, not war violence, accounted for PTSD symptoms in the parent group (β = .253, p = .002). We conclude that, even in the context of severe war, the impact of child maltreatment on psychological disorders surpasses the damage of war trauma. PMID:24478246

  20. Anomalies in cosmic rays: New particles versus charm?

    NASA Technical Reports Server (NTRS)

    Balayan, G. L.; Khodjamirian, A. Y.; Oganessian, A. G.

    1985-01-01

    For a long time two anomalies are observed in cosmic rays at energies E approx. = 100 TeV: (1) the generation of long-flying cascades in the hadron calorimeter (the so-called Tien-Shan effect) and; (2) the enhancement of direct muon yield as compared with the accelerator energy region. The aim is to discuss the possibility that both anomalies have common origins arising from production and decays of the same particles. the main conclusions are the following: (1) direct muons cannot be generated by any new particles with mass exceeding 10+20 GeV; and (2) if both effects are originated from the charmed hadrons, then the needed charm hadroproduction cross section is unexpectedly large as compared with the quark-gluon model predictions.

  1. Challenges in detecting genomic copy number aberrations using next-generation sequencing data and the eXome Hidden Markov Model: a clinical exome-first diagnostic approach.

    PubMed

    Yamamoto, Toshiyuki; Shimojima, Keiko; Ondo, Yumiko; Imai, Katsumi; Chong, Pin Fee; Kira, Ryutaro; Amemiya, Mitsuhiro; Saito, Akira; Okamoto, Nobuhiko

    2016-01-01

    Next-generation sequencing (NGS) is widely used for the detection of disease-causing nucleotide variants. The challenges associated with detecting copy number variants (CNVs) using NGS analysis have been reported previously. Disease-related exome panels such as Illumina TruSight One are more cost-effective than whole-exome sequencing (WES) because of their selective target regions (~21% of the WES). In this study, CNVs were analyzed using data extracted through a disease-related exome panel analysis and the eXome Hidden Markov Model (XHMM). Samples from 61 patients with undiagnosed developmental delays and 52 healthy parents were included in this study. In the preliminary study to validate the constructed XHMM system (microarray-first approach), 34 patients who had previously been analyzed by chromosomal microarray testing were used. Among the five CNVs larger than 200 kb that were considered as non-pathogenic CNVs and were used as positive controls, four CNVs was successfully detected. The system was subsequently used to analyze different samples from 27 patients (NGS-first approach); 2 of these patients were successfully diagnosed as having pathogenic CNVs (an unbalanced translocation der(5)t(5;14) and a 16p11.2 duplication). These diagnoses were re-confirmed by chromosomal microarray testing and/or fluorescence in situ hybridization. The NGS-first approach generated no false-negative or false-positive results for pathogenic CNVs, indicating its high sensitivity and specificity in detecting pathogenic CNVs. The results of this study show the possible clinical utility of pathogenic CNV screening using disease-related exome panel analysis and XHMM. PMID:27579173

  2. Challenges in detecting genomic copy number aberrations using next-generation sequencing data and the eXome Hidden Markov Model: a clinical exome-first diagnostic approach

    PubMed Central

    Yamamoto, Toshiyuki; Shimojima, Keiko; Ondo, Yumiko; Imai, Katsumi; Chong, Pin Fee; Kira, Ryutaro; Amemiya, Mitsuhiro; Saito, Akira; Okamoto, Nobuhiko

    2016-01-01

    Next-generation sequencing (NGS) is widely used for the detection of disease-causing nucleotide variants. The challenges associated with detecting copy number variants (CNVs) using NGS analysis have been reported previously. Disease-related exome panels such as Illumina TruSight One are more cost-effective than whole-exome sequencing (WES) because of their selective target regions (~21% of the WES). In this study, CNVs were analyzed using data extracted through a disease-related exome panel analysis and the eXome Hidden Markov Model (XHMM). Samples from 61 patients with undiagnosed developmental delays and 52 healthy parents were included in this study. In the preliminary study to validate the constructed XHMM system (microarray-first approach), 34 patients who had previously been analyzed by chromosomal microarray testing were used. Among the five CNVs larger than 200 kb that were considered as non-pathogenic CNVs and were used as positive controls, four CNVs was successfully detected. The system was subsequently used to analyze different samples from 27 patients (NGS-first approach); 2 of these patients were successfully diagnosed as having pathogenic CNVs (an unbalanced translocation der(5)t(5;14) and a 16p11.2 duplication). These diagnoses were re-confirmed by chromosomal microarray testing and/or fluorescence in situ hybridization. The NGS-first approach generated no false-negative or false-positive results for pathogenic CNVs, indicating its high sensitivity and specificity in detecting pathogenic CNVs. The results of this study show the possible clinical utility of pathogenic CNV screening using disease-related exome panel analysis and XHMM. PMID:27579173

  3. Charm and beauty physics at Fermilab

    SciTech Connect

    Lipton, R.

    1992-01-01

    The status of charm and beauty physics studies at Fermilab is reviewed. Data from fixed target experiments on charm production, semi-leptonic decay, and Cabibbo suppressed decays as well as charmonium studies in antiproton annihilation are described. In addition beauty results from CDF and E653 are reviewed and prospects for studies of B physics at collider detectors are discussed.

  4. Charm Baryon Results from BaBar

    SciTech Connect

    Ziegler, Veronique; /SLAC

    2012-04-27

    We present experimental results from the BaBar experiment on charm baryon spectroscopy and production studies, including studies of excited cascades produced in charm baryon decays. We review the discovery of new decay modes of known states and searches for predicted states.

  5. Charm Baryon Results from BaBar

    SciTech Connect

    Ziegler, Veronique

    2011-10-24

    We present experimental results from the BaBar experiment on charm baryon spectroscopy and production studies, including studies of excited cascades produced in charm baryon decays. We review the discovery of new decay modes of known states and searches for predicted states.

  6. Charm Physics at BaBar

    SciTech Connect

    Chen, Chunhui; /Maryland U.

    2005-06-29

    Large production of the c{bar c} pairs and high integrated luminosity make the PEPII B Factory an excellent place for studying the charm hadrons. In this paper, we present a few most recent results from BaBar collaboration in charm sector.

  7. Geometrical scaling in charm structure function ratios

    NASA Astrophysics Data System (ADS)

    Boroun, G. R.; Rezaei, B.

    2014-09-01

    By using a Laplace-transform technique, we solve the next-to-leading-order master equation for charm production and derive a compact formula for the ratio Rc = FLccbar/F2ccbar, which is useful for extracting the charm structure function from the reduced charm cross section, in particular, at DESY HERA, at small x. Our results show that this ratio is independent of x at small x. In this method of determining the ratios, we apply geometrical scaling in charm production in deep inelastic scattering (DIS). Our analysis shows that the renormalization scales have a sizable impact on the ratio Rc at high Q2. Our results for the ratio of the charm structure functions are in a good agreement with some phenomenological models.

  8. Recent charm physics results from CLEO

    SciTech Connect

    Fujino, D.H.; CLEO Collaboration

    1997-07-01

    In this talk I present recent charm physics results from the CLEO experiment. Final state interactions and W-annihilation effects in charmed mesons decays are discussed. These include an isospin analysis of D {yields} K{anti K}, observation of the candidate W- annihilation decay D{sup +}{sub s} {yields} {omega}{pi}{sup +}, and evidence of non-factorizable effects in D{sup +}{sub s} {yields} {eta}{pi}{sup +}, {eta}`{pi}{sup +}, {eta}{rho}{sup +}, and {eta}`{rho}{sup +} decays. Presented next are CLEO`s observations of the spin 3/2 {sup +} excited charmed baryons {Sigma}{sup *++}{sub c} and {Sigma}{sup *0}{sub c}, and the excited charmed-strange baryons {Xi}{sup *+}{sub c} and {Xi}{sup *0}{sub c}. I conclude with future prospects in charm physics with CLEO`s new silicon detector.

  9. Charmed hadron photoproduction at COMPASS

    NASA Astrophysics Data System (ADS)

    Wang, Xiao-Yun; Guskov, Alexey

    2016-06-01

    Photoproduction of the charmonium-like state Zc(4200) and the charmed baryon Λ_c^* (2940) is investigated with an effective Lagrangian approach and the Regge trajectories applying to the COMPASS experiment. Combining the experimental data from COMPASS and our theoretical model we estimate the upper limit of ΓZc(4200)→J/ψπ to be of about 37 MeV. Moreover, the possibility to produce Λ_c^* (2940) at COMPASS is discussed. It seems one can try to search for this hadron in the missing mass spectrum since the t-channel is dominating for the Λ_c^* (2940) photoproduction.

  10. J =3 /2 charmed hypertriton

    NASA Astrophysics Data System (ADS)

    Garcilazo, H.; Valcarce, A.; Caramés, T. F.

    2015-08-01

    By solving exact three-body equations, we study the three-baryon system with charm +1 . We look for possible bound states using baryon-baryon interactions obtained from a chiral constituent quark model. The smaller effect of the Λc↔Σc conversion reverses the order of the (I ,J )=(0 ,1 /2 ) and (I ,J )=(0 ,3 /2 ) states, rather close on the strange sector. The diminishing of the kinetic energy due to the large reduced mass gives rise to a bound state in the (I ,J )=(0 ,3 /2 ) channel. After correcting for Coulomb effects, the binding energy would be between 140 and 715 keV.

  11. Charm production in Pb + Pb collisions at energies available at the CERN Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Song, Taesoo; Berrehrah, Hamza; Cabrera, Daniel; Cassing, Wolfgang; Bratkovskaya, Elena

    2016-03-01

    We study charm production in Pb +Pb collisions at √{sN N}=2.76 TeV in the parton-hadron-string-dynamics (PHSD) transport approach and the charm dynamics in the partonic and hadronic medium. The charm quarks are produced through initial binary nucleon-nucleon collisions by using the pythia event generator, taking into account the (anti-)shadowing incorporated in the eps09 package. The produced charm quarks interact with off-shell massive partons in the quark-gluon plasma and are hadronized into D mesons through coalescence or fragmentation close to the critical energy density, and then interact with hadrons in the final hadronic stage with scattering cross sections calculated in an effective Lagrangian approach with heavy-quark spin symmetry. The PHSD results show a reasonable RAA and elliptic flow of D mesons in comparison to the experimental data for Pb +Pb collisions at √{sN N}=2.76 TeV from the ALICE Collaboration. We also study the effect of temperature-dependent off-shell charm quarks in relativistic heavy-ion collisions. We find that the scattering cross sections are only moderately affected by off-shell charm degrees of freedom. However, the position of the peak of RAA for D mesons depends on the strength of the scalar partonic forces which also have an impact on the D meson elliptic flow. The comparison with experimental data on the RAA suggests that the repulsive force is weaker for off-shell charm quarks as compared to that for light quarks. Furthermore, the effects from radiative charm energy loss appear to be low compared to the collisional energy loss up to transverse momenta of ˜15 GeV/c .

  12. Charmed Mesons in Nuclei with Heavy-Quark Spin Symmetry

    NASA Astrophysics Data System (ADS)

    Tolos, L.; Garcia-Recio, C.; Nieves, J.; Romanets, O.; Salcedo, L. L.

    2013-08-01

    We study the properties of charmed pseudoscalar and vector mesons in dense matter within a unitary meson-baryon coupled-channel model which incorporates heavy-quark spin symmetry. This is accomplished by extending the SU(3) Weinberg-Tomozawa Lagrangian to incorporate spin-flavor symmetry and implement a suitable flavor symmetry breaking. Several resonances with negative parity are generated dynamically by the s-wave interaction between pseudoscalar and vector meson multiplets with 1/2+ and 3/2+ baryons. Those states are then compared to experimental data as well as theoretical models. Next, Pauli-blocking effects and meson self-energies are introduced in a self-consistent manner to obtain the open-charm meson spectral functions in a dense nuclear environment. We finally discuss the formation of D-mesic nuclei.

  13. CHARM 2010: Experiment summary and future charm facilities

    SciTech Connect

    Appel, Jeffrey A.; /Fermilab

    2010-12-01

    The CHARM 2010 meeting had over 30 presentations of experimental results, plus additional future facilities talks just before this summary talk. Since there is not enough time to even summarize all that has been shown from experiments and to recognize all the memorable plots and results - tempting as it is to reproduce the many clean signals and data vs theory figures, the quantum correlations plots, and the D-mixing plots before and after the latest CLEO-c data is added. So, this review will give only my personal observations, exposing my prejudices and my areas of ignorance, no doubt. This overview will be at a fairly high level of abstraction - no re-showing individual plots or results. I ask the forgiveness of those who will have been slighted in this way - meaning all the presents.

  14. Problem of hidden variables

    NASA Astrophysics Data System (ADS)

    Santos, Emilio

    1992-10-01

    The problem of hidden variables in quantum mechanics is formalized as follows. A general or contextual (noncontextual) hidden-variables theory is defined as a mapping f: Q×M → C (f: Q→C) where Q is the set of projection operators in the appropriate (quantum) Hilbert space, M is the set of maximal Boolean subalgebras of Q and C is a (classical) Boolean algebra. It is shown that contextual (noncontextual) hidden-variables always exist (do not exist).

  15. From the {psi} to charmed mesons

    SciTech Connect

    Goldhaber, G. |

    1994-11-01

    This talk deals with the author`s recollections about the discoveries of the J/{psi} the {psi}{prime} as well as psion spectroscopy and charmed mesons. He gives a chronology for the {psi} and {psi}{prime} discoveries. He also discusses the events which led to the charmed meson discovery as well as detailed discussions on the proof that the resonance observed in the K{sup {minus}} {pi}{sup +} system, at 1,865 MeV, was indeed the predicted charmed meson.

  16. Decays of doubly charmed meson molecules

    NASA Astrophysics Data System (ADS)

    Molina, R.; Nagahiro, H.; Hosaka, A.

    2016-01-01

    If the X(3872), Y(3940) and X(4160) are D*D ¯+c .c ., D*D ¯* and DS*D¯S* molecules, respectively, there should be doubly charmed mesons (D(*)D(*)). In this talk we predict two states with JP = 1+ in the charm = 2 sector, one DD* state around 3850 MeV, other D*D* state with mass around 3970 MeV, and other two similar states in the (charm = 2; strangeness = sector. Besides that, we evaluate the decay widths of doubly charm mesons D*D*(1+), into DDπ and DDγ. These decays are mediated by anomalous couplings D*D* - DD*, with the subsequent decay of D* into Dπ or Dγ.

  17. Probing new physics in rare charm processes

    SciTech Connect

    Hewett, J.L.

    1994-09-01

    The possibility of using the charm system to search for new physics is addressed. Phenomena such as D{sup 0} - {bar D}{sup 0} mixing and rare decays of charmed mesons are first examined in the Standard Model to test the present understanding and to serve as benchmarks for signals from new sources. The effects of new physics from various classes of non-standard dynamical models on D{sup 0} - {bar D}{sup 0} mixing are investigated.

  18. Charm, beauty and top at HERA

    NASA Astrophysics Data System (ADS)

    Behnke, O.; Geiser, A.; Lisovyi, M.

    2015-09-01

    Results on open charm and beauty production and on the search for top production in high-energy electron-proton collisions at HERA are reviewed. This includes a discussion of relevant theoretical aspects, a summary of the available measurements and measurement techniques, and their impact on improved understanding of QCD and its parameters, such as parton density functions and charm- and beauty-quark masses. The impact of these results on measurements at the LHC and elsewhere is also addressed.

  19. A Study of Double-Charm and Charm-Strange Baryons inElectron-Positron Annihilations

    SciTech Connect

    Edwards, Adam J.; /SLAC

    2007-10-15

    In this dissertation I describe a study of double-charm and charm-strange baryons based on data collected with the BABAR Detector at the Stanford Linear Accelerator Center. In this study I search for new baryons and make precise measurements of their properties and decay modes. I seek to verify and expand upon double-charm and charm-strange baryon observations made by other experiments. The BABAR Detector is used to measure subatomic particles that are produced at the PEP-II storage rings. I analyze approximately 300 million e+e- {yields} c{bar c} events in a search for the production of double-charm baryons. I search for the double-charm baryons {Xi}{sup +}{sub cc} (containing the quarks ccd) and {Xi}{sup ++}{sub cc} (ccu) in decays to {Lambda}{sup +}{sub c}K{sup -}{pi}{sup +} and {Lambda}{sup +}{sub c}K{sup -}{pi}{sup +}{pi}{sup +}, respectively. No statistically significant signals for their production are found, and upper limits on their production are determined. Statistically significant signals for excited charm-strange baryons are observed with my analysis of approximately 500 million e+e- {yields} c{bar c} events. The charged charm-strange baryons {Xi}{sub c}(2970){sup +}, {Xi}{sub c}(3055){sup +}, {Xi}{sub c}(3123){sup +} are found in decays to {Lambda}{sup +}{sub c}K{sup -}{pi}{sup +}, the same decay mode used in the {Xi}{sup +}{sub cc} search. The neutral charm-strange baryon {Xi}{sub c}(3077){sup 0} is observed in decays to {Lambda}{sup +}{sub c}K{sub 8}{pi}{sup -}. I also search for excited charm-strange baryon decays to {Lambda}{sup +}{sub c}K{sub 8}, {Lambda}{sup +}{sub c}K{sup -}, {Lambda}{sup +}{sub c}K{sub 8}{pi}{sup -}{pi}{sup +}, and {Lambda}{sup +}{sub c}K{sup -}{pi}{sup -}{pi}{sup +}. No significant charm-strange baryon signals a f h these decay modes. For each excited charm-strange baryon state that I observe, I measure its mass, natural width (lifetime), and production rate. The properties of these excited charm-strange baryons and their

  20. Intrinsic charm in a matched general-mass scheme

    NASA Astrophysics Data System (ADS)

    Ball, Richard D.; Bertone, Valerio; Bonvini, Marco; Forte, Stefano; Groth Merrild, Patrick; Rojo, Juan; Rottoli, Luca

    2016-03-01

    The FONLL general-mass variable-flavour number scheme provides a framework for the matching of a calculation in which a heavy quark is treated as a massless parton to one in which the mass dependence is retained throughout. We describe how the usual formulation of FONLL can be extended in such a way that the heavy quark parton distribution functions are freely parameterized at some initial scale, rather than being generated entirely perturbatively. We specifically consider the case of deep-inelastic scattering, in view of applications to PDF determination, and the possible impact of a fitted charm quark distribution on F2c is assessed.

  1. The hidden universe

    SciTech Connect

    Disney, M.

    1985-01-01

    Astronomer Disney has followed a somewhat different tack than that of most popular books on cosmology by concentrating on the notion of hidden (as in not directly observable by its own radiation) matter in the universe.

  2. Search for threshold enhancement in the. gamma. p. -->. charmed baryon+charmed meson cross section

    SciTech Connect

    Abe, K.; Bacon, T.C.; Bingham, H.H.; Brau, J.E.; Braune, K.; Brick, D.; Bugg, W.M.; Butler, J.M.; Cameron, W.; Cohen, H.O.; Colley, D.C.; Dado, S.; Dingus, P.; Erickson, R.; Field, R.C.; Franek, B.; Gearhart, R.; Glanzman, T.; Godfrey, I.M.; Hall, G.; Hancock, E.R.; Hargis, H.J.; Hart, E.L.; Harwin, M.J.; Hasegawa, K.; Hulsizer, R.I.; Jobes, M.; Kafka, T.; Kalmus, G.E.; Kelsey, D.P.; Kitagaki, T.; Levy, A.; Merenyi, R.; Murray, J.J.; O'Dell, V.; Pless, I.A.; Rankin, P.; Ronat, E.; Sagawa, H.; Sewell, S.J.; Shank, J.; Shimony, J.; Tamai, K.; Tanaka, S.; Waide, D.A.; Widgoff, M.; Wolbers, S.; Woods, C.A.; Yamaguchi, A.; Yamamoto, R.K.; Yost, G.P.; Yuta, H.

    1984-08-01

    Results of a search for a predicted enhancement of several microbarns in the charm-photoproduction cross section just above threshold are reported. No charm decays were detected, from which an upper limit to the charm cross section of 94 nb (90% C.L.) at E/sub ..gamma../approx. =10 GeV was obtained. Upper limits in the range 270 to 450 nb were also obtained for the peak cross sections for threshold enhancements in ..gamma..p..-->..D/sup -/..sigma../sub c//sup + +/ and similar channels.

  3. Probing the Charm Quark Yukawa Coupling in Higgs+Charm Production.

    PubMed

    Brivio, Ilaria; Goertz, Florian; Isidori, Gino

    2015-11-20

    We propose a new method for determining the coupling of the Higgs boson to charm quarks, via Higgs production in association with a charm-tagged jet: pp→hc. As a first estimate, we find that at the LHC with 3000 fb^{-1}, it should be possible to derive a constraint of order one, relative to the standard model (SM) value of the charm Yukawa coupling. As a by-product of this analysis, we present an estimate of the exclusive pp→hD^{(*)} electroweak cross section. Within the SM, the latter turns out to be not accessible at the LHC even in the high-luminosity phase. PMID:26636844

  4. Random graphs with hidden color.

    PubMed

    Söderberg, Bo

    2003-07-01

    We propose and investigate a unifying class of sparse random graph models, based on a hidden coloring of edge-vertex incidences, extending an existing approach, random graphs with a given degree distribution, in a way that admits a nontrivial correlation structure in the resulting graphs. The approach unifies a number of existing random graph ensembles within a common general formalism, and allows for the analytic calculation of observable graph characteristics. In particular, generating function techniques are used to derive the size distribution of connected components (clusters) as well as the location of the percolation threshold where a giant component appears. PMID:12935185

  5. Charm and beauty production at CDF

    SciTech Connect

    Bishai, M.; /Brookhaven

    2005-01-01

    Using the data samples collected with the CDF Run II detector during 2002 and early 2003, new measurements of the production cross sections of charm and beauty hadrons at {radical}s = 1960 GeV are presented. New measurements of the cross sections of centrally produced b-hadrons and J/{psi} mesons down to zero transverse momenta have been carried out. The large charm signals made available by the silicon vertex track trigger have enabled the measurement of the cross sections of D{sup 0}, D*, D{sup {+-}}, and D{sub s} mesons.

  6. Charm (and Beauty) Production at the Tevatron

    SciTech Connect

    Rademacker, Jonas; /Bristol U.

    2007-11-01

    The authors present recent results on heavy flavor production at Tevatron Run II for typically {approx} 1 fb{sup -1} of analyzed p{bar p} data at {radical}s = 1.96 TeV. This includes results on single and correlated open charm and bottom cross sections, charm pair production kinematics, J/{psi}, {psi}(2S) and {chi}{sub cJ} cross sections and polarization measurements in J/{psi}, {psi}(2S), {Upsilon}(1S), and {Upsilon}(2S).

  7. Update on hadroproduced charm at TPL

    SciTech Connect

    Thorne, Keith

    1992-06-01

    Two experiments have now been run at Fermilab using the Tagged Photon Laboratory (TPL) spectrometer with an incident hadron beam to study heavy quark physics. Results (preliminary) from the first experiment, E-769, on charm hadroproduction dependence on the target atomic number, x{sub F} and p{sub t} are presented. The next experiment, E-791, just completed data-taking with an upgraded spectrometer and data-acquisition system to collect a high-statistics sample of charm decays. Preliminary plots and estimates of final sample size are presented.

  8. Charm and Beauty in Photoproduction at HERA

    NASA Astrophysics Data System (ADS)

    Dobre, Monica

    2014-04-01

    The photoproduction of beauty and charm quarks at the ep collider HERA are presented. The b-quarks production was investigated in the bb → eeX' channel and the differential production cross section was measured as a function of the average transverse momentum of the beauty quarks down to the threshold. The cross section of D* meson decaying in the golden channel was determined both inclusively and in D*-tagged dijet events. Exploiting the characteristics of the heavy-flavoured hadron decays, beauty and charm quark cross sections were also measured in dijet events using secondary vertices or semi-muonic decays.

  9. Thermal charm and charmonium production in quark gluon plasma

    NASA Astrophysics Data System (ADS)

    Zhou, Kai; Chen, Zhengyu; Greiner, Carsten; Zhuang, Pengfei

    2016-07-01

    We study the effect of thermal charm production on charmonium regeneration in high energy nuclear collisions. By solving the kinetic equations for charm quark and charmonium distributions in Pb+Pb collisions, we calculate the global and differential nuclear modification factors RAA (Npart) and RAA (pt) for J / ψ s. Due to the thermal charm production in hot medium, the charmonium production source changes from the initially created charm quarks at SPS, RHIC and LHC to the thermally produced charm quarks at Future Circular Collider (FCC), and the J / ψ suppression (RAA < 1) observed so far will be replaced by a strong enhancement (RAA > 1) at FCC at low transverse momentum.

  10. Charm contribution to the atmospheric neutrino flux

    NASA Astrophysics Data System (ADS)

    Halzen, Francis; Wille, Logan

    2016-07-01

    We revisit the estimate of the charm particle contribution to the atmospheric neutrino flux that is expected to dominate at high energies because long-lived high-energy pions and kaons interact in the atmosphere before decaying into neutrinos. We focus on the production of forward charm particles which carry a large fraction of the momentum of the incident proton. In the case of strange particles, such a component is familiar from the abundant production of K+Λ pairs. These forward charm particles can dominate the high-energy atmospheric neutrino flux in underground experiments. Modern collider experiments have no coverage in the very large rapidity region where charm forward pair production dominates. Using archival accelerator data as well as IceCube measurements of atmospheric electron and muon neutrino fluxes, we obtain an upper limit on forward D¯0Λc pair production and on the associated flux of high-energy atmospheric neutrinos. We conclude that the prompt flux may dominate the much-studied central component and represent a significant contribution to the TeV atmospheric neutrino flux. Importantly, it cannot accommodate the PeV flux of high-energy cosmic neutrinos, or the excess of events observed by IceCube in the 30-200 TeV energy range indicating either structure in the flux of cosmic accelerators, or a presence of more than one component in the cosmic flux observed.

  11. Spectroscopy and decays of charm and bottom

    SciTech Connect

    Butler, J.N.

    1997-10-01

    After a brief review of the quark model, we discuss our present knowledge of the spectroscopy of charm and bottom mesons and baryons. We go on to review the lifetimes, semileptonic, and purely leptonic decays of these particles. We conclude with a brief discussion B and D mixing and rare decays.

  12. Predicting the Total Charm Cross Section

    SciTech Connect

    Vogt, R

    2008-05-29

    We discuss the energy dependence of the total charm cross section and some of its theoretical uncertainties including the quark mass, scale choice and the parton densities. Extracting the total charm cross section from data is a non-trivial task. To go from a finite number of measured D mesons in a particular decay channel to the total c{bar c} cross section one must: divide by the branching ratio for that channel; correct for the luminosity, {sigma}{sub D} = N{sub D}/Lt; extrapolate to full phase space from the finite detector acceptance; divide by two to get the pair cross section from the single Ds; and multiply by a correction factor to account for unmeasured charm hadrons. Early fixed-target data were at rather low p{sub T}, making the charm quark mass the most relevant scale. At proton and ion colliders, although the RHIC experiments can access the full pT range and thus the total cross section, the data reach rather high p{sub T}, p{sub T} >> m, making p{sub T} (m{sub T}) the most relevant scale. Here we focus on the total cross section calculation where the quark mass is the only relevant scale.

  13. Photoproduction of charm particles at Fermilab

    SciTech Connect

    Cumalat, John P.

    1997-03-15

    A brief description of the Fermilab Photoproduction Experiment E831 or FOCUS is presented. The experiment concentrates on the reconstruction of charm particles. The FOCUS collaboration has participants from several Central American and Latin American institutions; CINVESTAV and Universidad Autonoma de Puebla from Mexico, University of Puerto Rico from the United States, and Centro Brasileiro de Pesquisas Fisicas in Rio de Janeiro from Brasil.

  14. Detecting targets hidden in random forests

    NASA Astrophysics Data System (ADS)

    Kouritzin, Michael A.; Luo, Dandan; Newton, Fraser; Wu, Biao

    2009-05-01

    Military tanks, cargo or troop carriers, missile carriers or rocket launchers often hide themselves from detection in the forests. This plagues the detection problem of locating these hidden targets. An electro-optic camera mounted on a surveillance aircraft or unmanned aerial vehicle is used to capture the images of the forests with possible hidden targets, e.g., rocket launchers. We consider random forests of longitudinal and latitudinal correlations. Specifically, foliage coverage is encoded with a binary representation (i.e., foliage or no foliage), and is correlated in adjacent regions. We address the detection problem of camouflaged targets hidden in random forests by building memory into the observations. In particular, we propose an efficient algorithm to generate random forests, ground, and camouflage of hidden targets with two dimensional correlations. The observations are a sequence of snapshots consisting of foliage-obscured ground or target. Theoretically, detection is possible because there are subtle differences in the correlations of the ground and camouflage of the rocket launcher. However, these differences are well beyond human perception. To detect the presence of hidden targets automatically, we develop a Markov representation for these sequences and modify the classical filtering equations to allow the Markov chain observation. Particle filters are used to estimate the position of the targets in combination with a novel random weighting technique. Furthermore, we give positive proof-of-concept simulations.

  15. Spectroscopy of doubly charmed baryons from lattice QCD

    SciTech Connect

    Padmanath, M.; Edwards, Robert G.; Mathur, Nilmani; Peardon, Michael

    2015-05-06

    This study presents the ground and excited state spectra of doubly charmed baryons from lattice QCD with dynamical quark fields. Calculations are performed on anisotropic lattices of size 16³ × 128, with inverse spacing in temporal direction at⁻¹=5.67(4) GeV and with a pion mass of about 390 MeV. A large set of baryonic operators that respect the symmetries of the lattice yet which retain a memory of their continuum analogues are used. These operators transform as irreducible representations of SU(3)F symmetry for flavor, SU(4) symmetry for Dirac spins of quarks and O(3) for spatial symmetry. The distillation method is utilized to generate baryon correlation functions which are analyzed using the variational fitting method to extract excited states. The lattice spectra obtained have baryonic states with well-defined total spins up to 7/2 and the pattern of low-lying states does not support the diquark picture for doubly charmed baryons. On the contrary the calculated spectra are remarkably similar to the expectations from models with an SU(6)×O(3) symmetry. Various spin-dependent energy splittings between the extracted states are also evaluated.

  16. Spectroscopy of doubly charmed baryons from lattice QCD

    NASA Astrophysics Data System (ADS)

    Padmanath, M.; Edwards, Robert G.; Mathur, Nilmani; Peardon, Michael; Hadron Spectrum Collaboration

    2015-05-01

    We present the ground and excited state spectra of doubly charmed baryons from lattice QCD with dynamical quark fields. Calculations are performed on anisotropic lattices of size 1 63×128 , with inverse spacing in temporal direction at-1=5.67 (4 ) GeV and with a pion mass of about 390 MeV. A large set of baryonic operators that respect the symmetries of the lattice yet which retain a memory of their continuum analogues are used. These operators transform as irreducible representations of SU(3 ) F symmetry for flavor, SU(4) symmetry for Dirac spins of quarks and O(3) for spatial symmetry. The distillation method is utilized to generate baryon correlation functions which are analyzed using the variational fitting method to extract excited states. The lattice spectra obtained have baryonic states with well-defined total spins up to 7 /2 and the pattern of low-lying states does not support the diquark picture for doubly charmed baryons. On the contrary the calculated spectra are remarkably similar to the expectations from models with an SU (6 )×O (3 ) symmetry. Various spin-dependent energy splittings between the extracted states are also evaluated.

  17. Hazing: Hidden Campus Crime.

    ERIC Educational Resources Information Center

    Hollmann, Barbara B.

    2002-01-01

    Initiation traditions and rites of passage are important for group and team membership, but the violent behavior and alcohol abuse involved in hazing constitute serious campus crime. This article helps campus administrators to develop new strategies for attacking the hidden crime of hazing. (Contains 32 references.) (Author)

  18. Charmed spectroscopy from a nonperturbatively determined relativistic heavy quark action in full QCD

    SciTech Connect

    Huey-Wen Lin

    2006-07-28

    We present a preliminary calculation of the charmed meson spectrum using the 2+1 flavor domain wall fermion lattice configurations currently being generated by the RBC and UKQCD collaborations. The calculation is performed using the 3-parameter, relativistic heavy quark action with nonperturbatively determined coefficients. We will also demonstrate a step-scaling procedure for determining these coefficients nonperturbatively using a series of quenched, gauge field ensembles generated for three different lattice spacings.

  19. Abelian Hidden Sectors at a GeV

    SciTech Connect

    Morrissey, David E.; Poland, David; Zurek, Kathryn; /Fermilab /Michigan U.

    2009-04-16

    We discuss mechanisms for naturally generating GeV-scale hidden sectors in the context of weak-scale supersymmetry. Such low mass scales can arise when hidden sectors are more weakly coupled to supersymmetry breaking than the visible sector, as happens when supersymmetry breaking is communicated to the visible sector by gauge interactions under which the hidden sector is uncharged, or if the hidden sector is sequestered from gravity-mediated supersymmetry breaking. We study these mechanisms in detail in the context of gauge and gaugino mediation, and present specific models of Abelian GeV-scale hidden sectors. In particular, we discuss kinetic mixing of a U(1){sub x} gauge force with hypercharge, singlets or bi-fundamentals which couple to both sectors, and additional loop effects. Finally, we investigate the possible relevance of such sectors for dark matter phenomenology, as well as for low- and high-energy collider searches.

  20. Leading Charm in Hadron-Nucleus Interaction in the Intrinsic Charm Model

    SciTech Connect

    Gutierrez, T.; Vogt, R.

    1998-08-03

    Leading charm hadrons produced in hadron-nucleus interactions cannot be adequately described within the parton fusion model. Recent results on charm baryon production in Sigma{sup -} A interactions at 330 GeV with the WA89 detector disagree with fusion predictions. Intrinsic heavy quark pairs in the Sigma{sup -}(dds) wave function provide a simple mechanism for producing fast charm hadrons. We calculate leading charm baryon production from Sigma{sup -}, pi{sup -} and p projectiles in a two component model combining partonfusion with intrinsic charm. Final state D{sup -}, Sigma{sub c}{sup 0}, Xi{sub c}{sup +}, and Lambda{sub c}{sup +} d sigma/dx{sub F} distributions and D{sup -}/D{sup +}, D{sub s}{sup -}/D{sub s}{sup +} and Lambda{sub c}{sup +}/overline Lambda{sub c}{sup +} asymmetries are compared to WA89 data. Predictions are made for 650 GeV Sigma{sup -} A and pi{sup -} A interactions in the SELEX detector at Fermilab and for 800 GeV pA interactions.

  1. Charmed-strange mesons revisited: Mass spectra and strong decays

    NASA Astrophysics Data System (ADS)

    Song, Qin-Tao; Chen, Dian-Yong; Liu, Xiang; Matsuki, Takayuki

    2015-03-01

    Inspired by the present experimental status of charmed-strange mesons, we perform a systematic study of the charmed-strange meson family in which we calculate the mass spectra of the charmed-strange meson family by taking a screening effect into account in the Godfrey-Isgur model and investigate the corresponding strong decays via the quark pair creation model. These phenomenological analyses of charmed-strange mesons not only shed light on the features of the observed charmed-strange states, but also provide important information on future experimental search for the missing higher radial and orbital excitations in the charmed-strange meson family, which will be a valuable task in LHCb, the forthcoming Belle II, and PANDA.

  2. Charm degrees of freedom in the quark gluon plasma

    DOE PAGESBeta

    Mukherjee, Swagato; Petreczky, Peter; Sharma, Sayantan

    2016-01-11

    The lattice QCD studies on fluctuations and correlations of charm quantum number have established that deconfinement of charm degrees of freedom sets in around the chiral crossover temperature, Tc; i.e., charm degrees of freedom carrying fractional baryonic charge start to appear. When we reexamine those same lattice QCD data we show that, in addition to the contributions from quarklike excitations, the partial pressure of charm degrees of freedom may still contain significant contributions from open-charm-meson- and baryonlike excitations associated with integral baryonic charges for temperatures up to 1.2Tc. Finally, charm-quark quasiparticles become the dominant degrees of freedom for temperatures T>1.2Tc.

  3. Charm Spectroscopy at BaBar

    SciTech Connect

    Poireau, Vincent; /Annecy, LAPP

    2007-12-21

    We present a mini-review on charm spectroscopy at the BABAR experiment. We first report on the c{bar s} meson spectrum, and present precise measurements of the D{sub s1}(2536) meson as well as the properties of the many new states discovered since 2003 (D*{sub s0}(2317), D{sub s1}(2460), D*{sub sJ}(2860), and D{sub sJ}(2700) mesons). We then discuss about charmed baryons observed recently in the BABAR experiment: {Omega}{sub c}{sup 0} and {Omega}*{sub c}{sup 0} css baryons, {Lambda}{sub c}(2940){sup +} udc baryon and the {Xi}{sub c} usc/dsc baryons.

  4. Kondo effect in charm and bottom nuclei

    NASA Astrophysics Data System (ADS)

    Yasui, Shigehiro

    2016-06-01

    The Kondo effect for isospin-exchange interaction between a D ¯, B meson and a valence nucleon in charm and bottom atomic nuclei including the discrete energy levels for valence nucleons is discussed. To investigate the binding energy by the Kondo effect, I introduce the mean-field approach for the bound state of the D ¯, B meson in charm and bottom nuclei. Assuming a simple model, I examine the validity of the mean-field approximation by comparing the results with the exact solutions. The effect of the quantum fluctuation is estimated beyond the mean-field approximation. The competition between the Kondo effect and the other correlations in valence nucleons, the isospin symmetry breaking and the nucleon pairings, are discussed.

  5. Charming penguin contributions to B{r_arrow}K{pi}

    SciTech Connect

    Isola, C.; Ladisa, M.; Nardulli, G.; Pham, T. N.; Santorelli, P.

    2001-07-01

    We present calculations of the charming-penguin long-distance contributions to B{r_arrow}K{pi} decays due to intermediate charmed meson states. Our calculation is based on the chiral effective Lagrangian for light and heavy mesons, corrected for the hard pion and kaon momenta. We find that the charming-penguin contributions increase significantly the B{r_arrow}K{pi} decay rates in comparison with the short-distance contributions, giving results in better agreement with experimental data.

  6. Charm production in neutron-nucleon interactions

    SciTech Connect

    Tzeng, L.; McBride, P.L.; Cooper, P.S.; Li, Y.; Majka, R.D.; Sandweiss, J.; Slaughter, A.J.; Taft, H.D.; Teig, L.J.; Johnson, M.E.

    1985-09-09

    Hadronic production of charmed particles in association with muons from their semileptonic decay has been observed in a high-resolution streamer-chamber experiment performed at Fermilab. A miss-distance analysis of the pictures gives a signal of 17.3 +- 4.7 events. Depending on the production model this corresponds to a range of neutron-nucleon cross sections from 8 to 50 ..mu..b, assuming an A/sup 2/3/ dependence.

  7. Babar: Sin(2beta) With Charm

    SciTech Connect

    Grenier, P.; /Ecole Polytechnique /Clermont-Ferrand U.

    2006-04-12

    We present measurements of time-dependent CP asymmetries of neutral B decays to several charm and charmonium final states. Data have been collected with the BABAR detector at the PEP-II storage ring at the Stanford Linear Accelerator Center. In the absence of penguin contribution, the Standard Model predicts the time-dependent CP asymmetry parameters S and C are to be {eta}{sub CP} sin(2{beta}) and 0, respectively.

  8. The charm quark on the lattice

    NASA Astrophysics Data System (ADS)

    Kronfeld, Andreas S.

    1993-03-01

    We formulate lattice fermions in a way that encompasses Wilson fermions as well as the static and non-relativistic approximations. In particular, we treat mqα systematically ( mq is the fermion mass) showing show how to understand the Wilson action as an effective action for systems with p≪ mq. The results show how to extract matrix elements and the spectrum from simulations with mqa ≈ 1, which is relevant for the charm quark.

  9. Unsolved problems in hadronic charm decay

    SciTech Connect

    Browder, T.E.

    1989-08-01

    This paper describes several outstanding problems in the study of hadronic decays of charmed mesons where further experimental work and theoretical understanding is needed. Four topics are stressed: double Cabibbo suppressed decays (DCSD) of D/sup +/ mesons, hadronic D/sub s/ decays, weak hadronic quasi-two-body decays to pairs of vector mesons, and penguin decays of D mesons. 24 refs., 10 figs., 5 tabs.

  10. Study of correlations between photoproduced pairs of charmed particles at Experiment E831/FOCUS

    SciTech Connect

    Castromonte Flores, Cesar Manuel

    2008-08-01

    The authors present the study of the charm-pair correlations produced in photon-nucleon interactions at $\\langle$Eγ$\\rangle$ = 175 GeV/c, by the Fermilab fixed target experiment E831/FOCUS. The E831/FOCUS experiment produced and reconstructed over one million charm particles. This high statistics allows the reconstruction of more than 7000 charm-pair mesons D$\\bar{D}$, 10 times the statistic of former experiments, and also allows to get, for the first time, about 600 totally reconstructed charm-pairs in the DDs and DΛc channels. They were able to study, with some detail, the kinematical correlations between the charm and anticharm particle forming a pair, in the square transverse momentum (pT2), azimuthal angle difference (ΔΦ), rapidity difference (Δy) and the charm-pair mass variables. They observe some correlation for the longitudinal momenta, and a significant correlation for the transverse momenta of the charm and anticharm particles. They compare the experimental distributions with theoretical predictions based on the photon-gluon fusion model (PGF), for the production of c$\\bar{c}$ quarks, and the standard Lund hadronization model. These models are implemented by the PYTHIA Monte Carlo event generator. The PYTHIA program allows the inclusion, in the simulation, of non-perturbative effects that have been shown to be important for charm production. In order to compare data and simulation, they have generated two Monte Carlo samples, the first one set to favor the production of D$\\bar{D}$ pairs (MCDD2), and the second one set to favor the production of DDsand DΛc pairs, where each one uses different functions and parameters values for the theoretical models in the simulation. They observe, for the correlation distributions, that the set of parameters used by the MCDD2 model together with the intrinsic transverse momentum (k$\\perp$) of the partons inside the

  11. Lifetimes of charm and beauty hadrons

    NASA Astrophysics Data System (ADS)

    Bellini, G.; Bigi, I. I.; Dornan, P. J.

    1997-10-01

    Major breakthroughs have been achieved in the determination of the lifetimes of charm and beauty hadrons. Much larger data samples than previously have become available and new experimental devices and techniques have been developed and employed. The lifetimes of all weakly decaying singly charmed hadrons have been measured, some with an accuracy of a few percent. The difference in the shortest lifetime - τ(Ω c) - and the longest one - τ( D+) - is given by a factor of close to ten. The experimental status of beauty lifetimes, while less complete, has still reached a new level of quality and is now better than 5% for the commoner states. New theoretical tools, based mainly on heavy quark expansions, have been developed; they incorporate as well as transcend earlier phenomenological descriptions. The observed pattern in the charm lifetime ratios is reproduced in a semi-quantitative manner as well as could be expected; as far as the beauty lifetime ratios are concerned some problems may well be emerging. The maturity level achieved in the measurements bodes quite well for future challenges where reliable and efficient tracking of the decay vertices will be crucial.

  12. Testing discrete symmetries at a super τ -charm factory

    NASA Astrophysics Data System (ADS)

    Bevan, Adrian John

    2016-02-01

    Tests of discrete symmetry violation have played an important role in understanding the structure of weak interactions in the Standard Model of particle physics. Historically, these measurements have been extensively performed in experiments with large samples of K and B mesons. A high luminosity τ-charm facility presents physicists with the opportunity to comprehensively explore discrete symmetry violation and test the Standard Model using τ leptons, charm mesons, and charmed baryons. This paper discusses several possible measurements for a future τ-charm factory.

  13. Direct probe of the intrinsic charm content of the proton

    NASA Astrophysics Data System (ADS)

    Boettcher, Tom; Ilten, Philip; Williams, Mike

    2016-04-01

    Measurement of Z bosons produced in association with charm jets (Z c ) in proton-proton collisions in the forward region provides a direct probe of a potential nonperturbative (intrinsic) charm component in the proton wave function. We provide a detailed study of the potential to measure Z c production at the LHCb experiment in Runs 2 and 3 of the LHC. The sensitivity to valence-like (sea-like) intrinsic charm is predicted to be ⟨x ⟩IC≳0.3 %(1 %). The impact of intrinsic charm on Higgs production at the LHC, including H c , is also discussed in detail.

  14. SELEX: Recent Progress in the Analysis of Charm-Strange and Double-Charm Baryons

    SciTech Connect

    Engelfried, Jurgen

    2007-02-01

    SELEX (Fermilab Experiment 781) [1] employs beams of {Sigma}{sup -}, {pi}{sup -}, and protons at around 600 GeV/c to study production and decay properties of charmed baryons. It took data in the 1996/7 fixed target run and is currently analyzing those data. Here they focus on recently obtained results concerning the {Omega}{sub c}{sup 0} lifetime and the doubly-charmed baryons {Xi}{sub cc}{sup +} and {Xi}{sub cc}{sup ++}.

  15. Results on charm hadroproduction from CERN experiment WA82

    SciTech Connect

    Antinori, F.; Barberis, D.; Beusch, W.; Davenport, M.; Dufey, J.P.; French, B.R.; Harrison, K.; Jacholkowski, A.; Kirk, A.; Lamanna, E.; Lassalle, J.C.; Muller, F.; Redaelli, N.; Roda, C.; Weymann, M. ); Forino, A.; Gessaroli, R.; Mazzanti, P.; Quareni, A.; Viaggi, F. ); Anselmi, R.; Casanova, V.; Dameri, M.; Hurst, R.; Novelli, P.; Osculati, B.; Rossi, L.; Tomasini, G. ); Buys, A.; Grard, F.; Legros, P. ); Adamovich, M.; Alexandrov, Y.; Kharlamov, S.; Nechaeva, P.; Zavertyaev, M. )

    1992-02-01

    Experiment WA82 has collected data from 1987 to 1989 with the [Omega][prime] spectrometer at the CERN SPS. The aim of WA82 was a high statistics study of charm hadroproduction, using a silicon microstrip vertex detector and an impact parameter trigger. Latest results on the nuclear dependence of charm production and on the [ital x][sub [ital F

  16. Measurements of CP violation and mixing in charm decays

    NASA Astrophysics Data System (ADS)

    Contu, A.; LHCb Collaboration

    2016-07-01

    LHCb has collected the world's largest sample of charmed hadrons. This sample is used to search for direct and indirect CP violation in charm, and to measure D0 mixing parameters. New and updated measurements are presented, with complementary time-dependent and time-integrated analyses of D0 meson decays.

  17. Production of charmed mesons in Z decays

    NASA Astrophysics Data System (ADS)

    Buskulic, D.; de Bonis, I.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Pietrzyk, B.; Ariztizabal, F.; Comas, P.; Crespo, J. M.; Efthymiopoulos, I.; Fernandez, E.; Fernandez-Bosman, M.; Gaitan, V.; Garrido, Ll.; Mattison, T.; Orteu, S.; Pacheco, A.; Padilla, C.; Pascual, A.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Marinelli, N.; Natali, S.; Nuzzo, S.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Chai, Y.; Hu, H.; Huang, D.; Huang, X.; Lin, J.; Wang, T.; Xie, Y.; Xu, D.; Xu, R.; Zhang, J.; Zhang, L.; Zhao, W.; Bonvicini, G.; Boudreau, J.; Casper, D.; Drevermann, H.; Forty, R. W.; Ganis, G.; Gay, C.; Girone, M.; Hagelberg, R.; Harvey, J.; Hilgart, J.; Jacobsen, R.; Jost, B.; Knobloch, J.; Lehraus, I.; Maggi, M.; Markou, C.; Martinez, M.; Mato, P.; Meinhard, H.; Minten, A.; Miquel, R.; Moser, H.-G.; Palazzi, P.; Pater, J. R.; Perlas, J. A.; Perrodo, P.; Pusztaszeri, J.-F.; Ranjard, F.; Rolandi, L.; Rothberg, J.; Ruan, T.; Saich, M.; Schlatter, D.; Schmelling, M.; Sefkow, F.; Tejessy, W.; Tomalin, I. R.; Veenhof, R.; Wachsmuth, H.; Wasserbaech, S.; Wiedemann, W.; Wildish, T.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Bardadin-Otwinowska, M.; Barres, A.; Boyer, C.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Saadi, F.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Johnson, S. D.; Møllerud, R.; Nilsson, B. S.; Kyriakis, A.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Zachariadou, K.; Badier, J.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, B.; Fouque, G.; Passalacqua, L.; Rougé, A.; Rumpf, M.; Tanaka, R.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Veitch, E.; Focardi, E.; Moneta, L.; Parrini, G.; Corden, M.; Delfino, M.; Georgiopoulos, C.; Ikeda, M.; Jaffe, D. E.; Levinthal, D.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Pepe=Altarelli, M.; Salomone, S.; Colrain, P.; Ten Have, I.; Lynch, J. G.; Maitland, W.; Morton, W. T.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Smith, M. G.; Thompson, A. S.; Thorn, S.; Turnbull, R. M.; Brandl, B.; Braun, O.; Geweniger, C.; Graefe, G.; Hanke, P.; Hepp, V.; Karger, C.; Kluge, E. E.; Maumary, Y.; Putzer, A.; Rensch, B.; Stahl, A.; Tittel, K.; Wunsch, M.; Beuselinck, M.; Binnie, D. M.; Cameron, W.; Cattaneo, M.; Colling, D. J.; Dornan, P. J.; Hassard, J. F.; Lieske, N. M.; Moutoussi, A.; Nash, J.; Patton, S.; Payne, D. G.; Phillips, M. J.; San Martin, G.; Sedgbeer, J. K.; Wright, A. G.; Girtler, P.; Kuhn, D.; Rudolph, G.; Vogl, R.; Bowdery, C. K.; Brodbeck, T. J.; Finch, A. J.; Foster, F.; Hughes, G.; Jackson, D.; Keemer, N. R.; Nuttal, M.; Patel, A.; Sloan, T.; Snow, S. W.; Whelan, E. P.; Galla, A.; Greene, A. M.; Kleinknecht, K.; Raab, J.; Renk, B.; Sander, H.-G.; Schmidt, H.; Walther, S. M.; Wanke, R.; Wolf, B.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Calvet, D.; Carr, J.; Coyle, P.; Diaconu, C.; Drinkard, J.; Etienne, F.; Nicod, D.; Payre, P.; Roos, L.; Rousseau, D.; Schwemling, P.; Talby, M.; Adlung, S.; Assmann, R.; Bauer, C.; Blum, W.; Brown, D.; Cattaneo, P.; Dehning, B.; Dietl, H.; Dydak, F.; Frank, M.; Halley, A. W.; Jakobs, K.; Lauber, J.; Lütjens, G.; Lutz, G.; Männer, G.; Richter, R.; Schröder, J.; Schwarz, A. S.; Settles, R.; Seywerd, H.; Stierlin, H.; Stiegler, U.; Denis, R. St.; Wolf, G.; Alemany, R.; Boucrot, J.; Callot, O.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Janot, P.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Musolino, G.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Abbaneo, D.; Bagliesi, G.; Batignani, G.; Bottigli, U.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; Dell'Orso, R.; Ferrante, I.; Fidecaro, F.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Luisiani, A.; Mannelli, E. B.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Valassi, A.; Vannini, C.; Venturi, A.; Verdini, P. G.; Walsh, J.; Betteridge, A. P.; Gao, Y.; Green, M. G.; Johnson, D. L.; March, P. V.; Medcalf, T.; Mir, Ll. M.; Quazi, I. S.; Strong, J. A.; Bertin, V.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Edwards, M.; Norton, P. R.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Duarte, H.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Marx, B.; Perez, P.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Si Mohand, D.; Vallage, B.; Johnson, R. P.; Litke, A. M.; Taylor, G.; Wear, J.; Babbage, W.; Booth, C. N.; Buttar, C.; Cartwright, S.; Combley, F.; Dawson, I.; Thompson, L. F.; Barberio, E.; Böhrer, A.; Brandt, S.; Cowan, G.; Grupen, C.; Lutters, G.; Rivera, F.; Schäfer, U.; Smolik, L.; Bosisio, L.; Della Marina, R.; Giannini, G.; Bobbo, B.; Pitis, L.; Ragusa, F.; Bellantoni, L.; Chen, W.; Conway, J. S.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; Grahl, J.; Harton, J. L.; Hayes, O. J.; Nachtman, J. M.; Pan, Y. B.; Saadi, Y.; Schmitt, M.; Scott, I.; Sharma, V.; Shi, Z. H.; Turk, J. D.; Walsh, A. M.; Weber, F. V.; Wu, Sau Lan; Wu, X.; Zheng, M.; Zobernig, G.

    1994-03-01

    The production of charmed mesonsmathop {D^0 }limits^{( - )} , D ± , and D *± is studied in a sample of 478,000 hadronic Z decays. The production rates are measured to be 10052_2005_Article_BF01559519_TeX2GIFE1.gif begin{gathered} {Γ (Z to D^{* ± } X)}/{Γ _{had }} = 0.187 ± 0.015(exp .) ± 0.013(BR), \\ {Γ (Z to D^ ± X)}/{Γ _{had }} = 0.251 ± 0.026(exp .) ± 0.025(BR), \\ {Γ (Z to mathop {D^0 }limits^{( - )} X)}/{Γ _{had }} = 0.518 ± 0.052(exp .) ± 0.035(BR), \\ where the errors from this analysis are separated from those coming from the D branching ratios (BR). The D *± momentum distribution is extracted separately forZ to cbar c andZ to bbar b events with the help of event shape variables. It is consistent with the prediction of the JETSET Monte Carlo program after adjustment of the charm fragmentation function. Constraining the shape of theZ to bbar b contribution, the average fraction of the beam energy taken by a D * meson produced in the fragmentation of a charm quark is extracted by a parametric fit to be < X E > c =0.495±0.011±0.007. Evidence for D **0 ( D 1(2420)0 and/or D {2/*}(2460)0) production is found in theD^{* ± } π ^ mp channel, accounting for a fraction (18±5±2)% of all D *± production. The relative production of vector and pseudoscalar mesons is dicussed, together with the possible effects of D ** production. The c-quark forward-backward Z-pole asymmetry is detrmined from that of high momentum D *± to be A {/FB 0,c }=(7.7±4.4)%.

  18. Charge asymmetry in charmed-meson photoproduction

    SciTech Connect

    Berezhnoy, A. V. Likhoded, A. K.

    2006-01-15

    Within the perturbative-recombination model, the charge asymmetries in the D*{sup +}-D*{sup -}, D*{sup 0}-D*{sup 0}, and D{sup +}{sub s}-D{sup -}{sub s} yields are estimated under the kinematical conditions of the COMPASS experiment. Corrections that arise owing to the mass of a light quark in a charmed meson are taken into account. The yield of D{sup +}{sub s} mesons is predicted to be large in relation to the yield of D{sup -}{sub s} mesons.

  19. Development and implementation of (Q)SAR modeling within the CHARMMing web-user interface.

    PubMed

    Weidlich, Iwona E; Pevzner, Yuri; Miller, Benjamin T; Filippov, Igor V; Woodcock, H Lee; Brooks, Bernard R

    2015-01-01

    Recent availability of large publicly accessible databases of chemical compounds and their biological activities (PubChem, ChEMBL) has inspired us to develop a web-based tool for structure activity relationship and quantitative structure activity relationship modeling to add to the services provided by CHARMMing (www.charmming.org). This new module implements some of the most recent advances in modern machine learning algorithms-Random Forest, Support Vector Machine, Stochastic Gradient Descent, Gradient Tree Boosting, so forth. A user can import training data from Pubchem Bioassay data collections directly from our interface or upload his or her own SD files which contain structures and activity information to create new models (either categorical or numerical). A user can then track the model generation process and run models on new data to predict activity. PMID:25362883

  20. Development and implementation of (Q)SAR modeling within the CHARMMing Web-user interface

    PubMed Central

    Weidlich, Iwona E.; Pevzner, Yuri; Miller, Benjamin T.; Filippov, Igor V.; Woodcock, H. Lee; Brooks, Bernard R.

    2014-01-01

    Recent availability of large publicly accessible databases of chemical compounds and their biological activities (PubChem, ChEMBL) has inspired us to develop a Web-based tool for SAR and QSAR modeling to add to the services provided by CHARMMing (www.charmming.org). This new module implements some of the most recent advances in modern machine learning algorithms – Random Forest, Support Vector Machine (SVM), Stochastic Gradient Descent, Gradient Tree Boosting etc. A user can import training data from Pubchem Bioassay data collections directly from our interface or upload his or her own SD files which contain structures and activity information to create new models (either categorical or numerical). A user can then track the model generation process and run models on new data to predict activity. PMID:25362883

  1. Charmed bottom baryon spectroscopy from lattice QCD

    DOE PAGESBeta

    Brown, Zachary S.; Detmold, William; Meinel, Stefan; Orginos, Kostas

    2014-11-19

    In this study, we calculate the masses of baryons containing one, two, or three heavy quarks using lattice QCD. We consider all possible combinations of charm and bottom quarks, and compute a total of 36 different states with JP = 1/2+ and JP = 3/2+. We use domain-wall fermions for the up, down, and strange quarks, a relativistic heavy-quark action for the charm quarks, and nonrelativistic QCD for the bottom quarks. Our analysis includes results from two different lattice spacings and seven different pion masses. We perform extrapolations of the baryon masses to the continuum limit and to the physicalmore » pion mass using SU(4|2) heavy-hadron chiral perturbation theory including 1/mQ and finite-volume effects. For the 14 singly heavy baryons that have already been observed, our results agree with the experimental values within the uncertainties. We compare our predictions for the hitherto unobserved states with other lattice calculations and quark-model studies.« less

  2. Charm hadroproduction results from Fermilab E-400

    SciTech Connect

    Coteus, P.; Binkley, M.; Bossi, F.; Butler, J.; Cumalat, J.P.; DiCorato, M.; Diesburg, M.; Enagonio, J.; Filaseta, J.; Frabetti, P.L.

    1987-09-01

    Results are presented from Fermilab E-400 on the production of charmed baryons and mesons at a mean energy of 640 GeV. We show evidence for the charm-strange baryon, ..xi../sub c//sup +/, and present our measurements of its mass, width, lifetime, cross section and relative branching fractions, and the A, x/sub f/, p/sub t/, and particle/antiparticle dependence of the state. We show evidence for both the ..sigma../sub c//sup 2 +/ and ..sigma../sub c//sup 0/, and present measurements of three mass differences, ..sigma../sub c//sup 2 +/ - ..sigma../sub c//sup 0/, ..sigma../sub c//sup 0/ - ..lambda../sub c//sup +/, and ..sigma../sub c//sup 2 +/ - ..lambda../sub c//sup +/. Measurements of the A dependence and particle/antiparticle ratios for ..sigma../sub c/ production are also presented. We show preliminary results on the ratio of two decay modes of the D/sup 0/, D/sup 0/ ..-->.. K/sup +/K/sup -/ and D/sup 0/ ..-->.. K/sub 0/anti K/sub 0/. The latter mode has not been previously observed. 8 refs., 10 figs.

  3. The Italian Tau/charm project

    NASA Astrophysics Data System (ADS)

    Enrica Biagini, Maria

    2014-06-01

    A τ/charm Factory, an e + e- collider with very high luminosity at the 2-4.6 GeV center of mass energy, to be built on the Rome University at Tor Vergata campus, was studied by the Consortium Nicola Cabibbo Laboratory and the INFN Frascati Laboratories. This project is the natural evolution of the flagship Italian project SuperB Factory, funded by the Italian Government in 2010 with a budget that turned out to be insufficient to cover the total costs of the project. The study of rare events at the τ/charm energy was already planned as a Phase-II of SuperB [1]. This design keeps all the unique features of SuperB, including the polarization of the electron beam, with the possibility to take data in a larger energy range, with reduced accelerator dimensions and construction and operation costs. A Report on the accelerator design has been published in September 2013 [2].

  4. Lattice calculation of nonleptonic charm decays

    SciTech Connect

    Simone, J.N.

    1991-11-01

    The decays of charmed mesons into two body nonleptonic final states are investigated. Weak interaction amplitudes of interest in these decays are extracted from lattice four-point correlation functions using a effective weak Hamiltonian including effects to order G{sub f} in the weak interactions yet containing effects to all orders in the strong interactions. The lattice calculation allows a quantitative examination of non-spectator processes in charm decays helping to elucidate the role of effects such as color coherence, final state interactions and the importance of the so called weak annihilation process. For D {yields} K{pi}, we find that the non-spectator weak annihilation diagram is not small, and we interpret this as evidence for large final state interactions. Moreover, there is indications of a resonance in the isospin {1/2} channel to which the weak annihilation process contributes exclusively. Findings from the lattice calculation are compared to results from the continuum vacuum saturation approximation and amplitudes are examined within the framework of the 1/N expansion. Factorization and the vacuum saturation approximation are tested for lattice amplitudes by comparing amplitudes extracted from lattice four-point functions with the same amplitude extracted from products of two-point and three-point lattice correlation functions arising out of factorization and vacuum saturation.

  5. Charmed bottom baryon spectroscopy from lattice QCD

    SciTech Connect

    Brown, Zachary S.; Detmold, William; Meinel, Stefan; Orginos, Kostas

    2014-11-19

    In this study, we calculate the masses of baryons containing one, two, or three heavy quarks using lattice QCD. We consider all possible combinations of charm and bottom quarks, and compute a total of 36 different states with JP = 1/2+ and JP = 3/2+. We use domain-wall fermions for the up, down, and strange quarks, a relativistic heavy-quark action for the charm quarks, and nonrelativistic QCD for the bottom quarks. Our analysis includes results from two different lattice spacings and seven different pion masses. We perform extrapolations of the baryon masses to the continuum limit and to the physical pion mass using SU(4|2) heavy-hadron chiral perturbation theory including 1/mQ and finite-volume effects. For the 14 singly heavy baryons that have already been observed, our results agree with the experimental values within the uncertainties. We compare our predictions for the hitherto unobserved states with other lattice calculations and quark-model studies.

  6. Lepton mixing from the hidden sector

    NASA Astrophysics Data System (ADS)

    Ludl, P. O.; Smirnov, A. Yu.

    2015-10-01

    Experimental results indicate a possible relation between the lepton and quark mixing matrices of the form UPMNS≈VCKM†UX , where UX is a matrix with special structure related to the mechanism of neutrino mass generation. We propose a framework which can realize such a relation. The main ingredients of the framework are the double seesaw mechanism, SO(10) grand unification and a hidden sector of theory. The latter is composed of singlets (fermions and bosons) of the grand unified theory (GUT) symmetry with masses between the GUT and Planck scale. The interactions in this sector obey certain symmetries Ghidden. We explore the conditions under which symmetries Ghidden can produce flavor structures in the visible sector. Here the key elements are the basis-fixing symmetry and mediators which communicate information about properties of the hidden sector to the visible one. The interplay of SO(10) symmetry, basis-fixing symmetry identified as Z2×Z2 and Ghidden can lead to the required form of UX. A different kind of new physics is responsible for generation of the CKM mixing. We present the simplest realizations of the framework which differ by nature of the mediators and by symmetries of the hidden sector.

  7. Estimating Neuronal Ageing with Hidden Markov Models

    NASA Astrophysics Data System (ADS)

    Wang, Bing; Pham, Tuan D.

    2011-06-01

    Neuronal degeneration is widely observed in normal ageing, meanwhile the neurode-generative disease like Alzheimer's disease effects neuronal degeneration in a faster way which is considered as faster ageing. Early intervention of such disease could benefit subjects with potentials of positive clinical outcome, therefore, early detection of disease related brain structural alteration is required. In this paper, we propose a computational approach for modelling the MRI-based structure alteration with ageing using hidden Markov model. The proposed hidden Markov model based brain structural model encodes intracortical tissue/fluid distribution using discrete wavelet transformation and vector quantization. Further, it captures gray matter volume loss, which is capable of reflecting subtle intracortical changes with ageing. Experiments were carried out on healthy subjects to validate its accuracy and robustness. Results have shown its ability of predicting the brain age with prediction error of 1.98 years without training data, which shows better result than other age predition methods.

  8. Opportunities for high-sensitivity charm physics at Fermilab

    SciTech Connect

    Kaplan, D.M.; Burnstein, R.A.; Lederman, L.M.; Rubin, H.A.; Brown, C.N.; Christian, D.C.; Gelfand, N.M.; Kwan, S.W.; Chen, T.Y.; He, M.; Koetke, D.D.; Napier, A.; Papavassiliou, V.; Yu, X.Q.

    1996-07-01

    The CO initiative under consideration at Fermilab makes feasible a charm experiment reconstructing >10{sup 9} charm decays, four orders - of magnitude beyond the largest extant sample. The experiment might commence data-taking as early as 1999. In addition to programmatic charm physics such as spectroscopy, lifetimes, and QCD tests, it will have significant new-physics reach in the areas of CP violation, flavor-changing neutral-current and lepton-number-violating decays, and D{sup o} {bar D} {bar {sup o}} mixing, and should observe direct CP violation in Cabibbo-suppressed D decays if it occurs at the level predicted by the Standard Model.

  9. DO -- antiMixing and Rare Charm Decays

    SciTech Connect

    Miller, Jeanne M; Burdman, Gustavo

    2003-10-06

    We review the current status of flavor-changing neutral currents in the charm sector. We focus on the standard-model predictions and identify the main sources of theoretical uncertainties in both charm mixing and rare charm decays. The potential of these observables for constraining short-distance physics in the standard model and its extensions is compromised by the presence of large nonperturbative effects. We examine the possible discovery windows in which short-distance physics can be tested and study the effects of various extensions of the standard model. The current experimental situation and future prospects are reviewed.

  10. Hidden attractors in dynamical systems

    NASA Astrophysics Data System (ADS)

    Dudkowski, Dawid; Jafari, Sajad; Kapitaniak, Tomasz; Kuznetsov, Nikolay V.; Leonov, Gennady A.; Prasad, Awadhesh

    2016-06-01

    Complex dynamical systems, ranging from the climate, ecosystems to financial markets and engineering applications typically have many coexisting attractors. This property of the system is called multistability. The final state, i.e., the attractor on which the multistable system evolves strongly depends on the initial conditions. Additionally, such systems are very sensitive towards noise and system parameters so a sudden shift to a contrasting regime may occur. To understand the dynamics of these systems one has to identify all possible attractors and their basins of attraction. Recently, it has been shown that multistability is connected with the occurrence of unpredictable attractors which have been called hidden attractors. The basins of attraction of the hidden attractors do not touch unstable fixed points (if exists) and are located far away from such points. Numerical localization of the hidden attractors is not straightforward since there are no transient processes leading to them from the neighborhoods of unstable fixed points and one has to use the special analytical-numerical procedures. From the viewpoint of applications, the identification of hidden attractors is the major issue. The knowledge about the emergence and properties of hidden attractors can increase the likelihood that the system will remain on the most desirable attractor and reduce the risk of the sudden jump to undesired behavior. We review the most representative examples of hidden attractors, discuss their theoretical properties and experimental observations. We also describe numerical methods which allow identification of the hidden attractors.

  11. Puzzles in hyperon, charm and beauty physics.

    SciTech Connect

    Lipkin, H. J.

    2002-10-21

    Puzzles awaiting better experiments and better theory include: (1) the contradiction between good and bad SU(3) baryon wave functions in fitting Cabibbo theory for hyperon decays, strangeness suppression in the sea and the violation of the Gottfried Sum rule--no model fits all; (2) Anomalously enhanced Cabibbo-suppressed D{sup +} {yields} K*{sup +} (s{bar d}) decays; (3) anomalously enhanced and suppressed B {yields} {eta}{prime} X decays; (4) the OZI rule in weak decays; (5) Vector dominance (W {yields} {pi}, {rho}, a{sub 1}, D{sub s}, D*{sub s}) in weak decays; (6) puzzles in doubly-cabibbo-suppressed charm decays; and (7) problems in obtaining {Lambda} spin structure from polarization measurements of produced {Lambda}'s.

  12. Charm form factors in hadronic interactions

    SciTech Connect

    Bracco, M. E.; Navarra, F. S.; Nielsen, M.; Chiapparini, M.

    2010-12-28

    We calculate the form factors and the coupling constants in vertices with charm mesons, such as {rho}D*D*, in the framework of QCD sum rules. We first discuss the applications of these form factors in heavy ion collisions and in B decays. We then present an introduction to the method of QCD sum rules and describe how to work with the three-point function. We give special attention to the procedure employed to extrapolate results obtained in the deep euclidean region to the poles of the particles, located in the time-like region. Finally we present a table of ready-to-use parametrizations of all the form factors, which are relevant for the processes mentioned in the introduction. We also give the coupling constants.

  13. Rare charm and B decays at CDF

    SciTech Connect

    Julia Thom

    2003-12-15

    We present results on rare charm and B decays using 65pb{sup -1} of data taken with the CDF detector in Run II. Three results are discussed, a measurement of the relative branching ratios {Lambda}(D{sup 0} {yields} K{sup +}K{sup -})/{Lambda}(D{sup 0} {yields} K{pi}) and {Lambda}(D{sup 0} {yields} {pi}{sup +}{pi}{sup -})/{Lambda}(D{sup 0} {yields} K{pi}) and the direct CP-violating decay rate asymmetry, and a limit on the branching ratio of the FCNC decay D{sup 0} {yields} {mu}{sup +}{mu}{sup -}. We also discuss the prospects for the search for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays.

  14. Argonne Tau-charm factory collider design study

    SciTech Connect

    Teng, L.C.; Crosbie, E.A.; Norem, J.

    1995-12-01

    The design approach and design principles for a Tau-charm Factory at Argonne were studied. These studies led to a set of preliminary parameters and tentative component features as presented in this paper.

  15. Mesonic Decay of Charm Hypernuclei Λc+

    NASA Astrophysics Data System (ADS)

    Ghosh, Sabyasachi; Fontoura, Carlos E.; Krein, Gastão

    2016-03-01

    Λc+ hypernuclei are expected to have binding energies and other properties similar to those of strange hypernuclei in view of the similarity between the quark structures of the strange and charmed hyperons, namely Λ(uds) and Λc+(udc). One striking difference however occurs in their mesonic decays, as there is almost no Pauli blocking in the nucleonic decay of a charm hypernucleus because the final-state nucleons leave the nucleus at high energies. The nuclear medium nevertheless affects the mesonic decays of charm hypernucleus because the nuclear mean fields modify the masses of the charm hyperon. In the present communication we present results of a first investigation of the effects of finite baryon density on different weak mesonic decay channels of the Λc+ baryon. We found a non-negligible reduction of the decay widths as compared to their vacuum values.

  16. Simple estimates of the masses of pentaquarks with hidden beauty or strangeness

    NASA Astrophysics Data System (ADS)

    Kopeliovich, Vladimir; Potashnikova, Irina

    2016-04-01

    The masses of cryptoexotic pentaquarks with hidden beauty are estimated phenomenologically using the results by the LHCb Collaboration which discovered recently the cryptoexotic pentaquarks with hidden charm. The expected masses of the hidden beauty pentaquarks are about 10.8 GeV and 10.7 GeV in the limit of some kind of heavy quark symmetry. The states with hidden strangeness considered in a similar way have masses of about 2.37 GeV and 2.30 GeV, several hundred MeV higher than states discussed previously in connection with the relatively light positive strangeness pentaquark θ+. Empirical data on the spectra of pentaquarks can be used to get information about quarkonia interaction with nucleons. The results obtained for the case of heavy flavors are in fair agreement with the model of isospin (pion) exchange between flavored baryons and antiflavored vector mesons proposed by Karliner and Rosner, and in qualitative agreement with the bound-state version of the chiral soliton model.

  17. Hidden Magnetic Portals Around Earth

    NASA Video Gallery

    A NASA-sponsored researcher at the University of Iowa has developed a way for spacecraft to hunt down hidden magnetic portals in the vicinity of Earth. These gateways link the magnetic field of our...

  18. Ethics, Equity, and Hidden Privilege.

    ERIC Educational Resources Information Center

    Lawler, Patricia A.

    1996-01-01

    Issues of race and gender are often overlooked in ethical dilemmas. Adult educators must be aware of core professional values, thoughtfully analyze their biases, and acknowledge hidden privileges. (JOW)

  19. Child Abuse: The Hidden Bruises

    MedlinePlus

    ... AACAP Facts for Families Guide Skip breadcrumb navigation Child Abuse - The Hidden Bruises Quick Links Facts For Families ... 5; Updated November 2014 The statistics on physical child abuse are alarming. It is estimated hundreds of thousands ...

  20. Physics of a high-luminosity Tau-Charm Factory

    SciTech Connect

    King, M.E.

    1992-10-01

    This paper highlights the physics capabilities of a Tau-Charm Factory; i.e., high luminosity ({approximately}10{sup 33}cm{sup {minus}2}s{sup {minus}1}) e{sup +}e{sup {minus}} collider operating in the center-of-mass energy range of 3-5 GeV, with a high-precision, general-purpose detector. Recent developments in {tau} and charm physics are emphasized.

  1. Beauty and charm production at fixed-target experiments

    SciTech Connect

    Erik E. Gottschalk

    2003-12-10

    Fixed-target experiments continue to provide insights into the physics of particle production in strong interactions. The experiments are performed with different types of beam particles of varying energies, and many different target materials. Studies of beauty and charm production are of particular interest, since experimental results can be compared to perturbative QCD calculations. It is in this context that recent results from fixed-target experiments on beauty and charm production will be reviewed.

  2. Charm and bottom hadronic form factors with QCD sum rules

    SciTech Connect

    Bracco, M. E.; Rodrigues, B. O.; Cerqueira, A. Jr.

    2013-03-25

    We present a brief review of some calculations of form factors and coupling constants in vertices with charm and bottom mesons in the framework of QCD sum rules. We first discuss the motivation for this work, describing possible applications of these form factors to charm and bottom decays processes. We first make a summarize of the QCD sum rules method. We give special attention to the uncertainties of the method introducing by the intrinsic variation of the parameters. Finally we conclude.

  3. Hidden Statistics of Schroedinger Equation

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2011-01-01

    Work was carried out in determination of the mathematical origin of randomness in quantum mechanics and creating a hidden statistics of Schr dinger equation; i.e., to expose the transitional stochastic process as a "bridge" to the quantum world. The governing equations of hidden statistics would preserve such properties of quantum physics as superposition, entanglement, and direct-product decomposability while allowing one to measure its state variables using classical methods.

  4. Hidden asymmetry of ice.

    PubMed

    Kirov, Mikhail V

    2014-11-26

    Ice is a very complex and fundamentally important solid. In the present article, we review a new property of the hydrogen-bonded network in ice structures: an explicit nonequivalence of some antipodal configurations with the opposite direction of all hydrogen bonds (H-bonds). This asymmetry is most pronounced for the structures with considerable deviation of the H-bond network from the tetrahedral coordination. That is why we have investigated in detail four-coordinated ice nanostructures with no outer "dangling" hydrogen atoms, namely, ice bilayers and ice nanotubes consisting of stacked n-membered rings. The reason for this H-bonding asymmetry is a fundamental nonequivalence of the arrangements of water molecules in some antipodal configurations with the opposite direction of all H-bonds. For these configurations, the overall pictures of deviations of the hydrogen bonds from linearity are qualitatively different. We consider the reversal of all H-bonds as an additional nongeometric operation of symmetry, more precisely antisymmetry. It is not easy to find the explicit breaking of the symmetry of hydrogen bonding (H-symmetry) in the variety of all configurations. Therefore, this asymmetry may be named hidden. PMID:24905908

  5. Scale invariant extension of the standard model with a strongly interacting hidden sector.

    PubMed

    Hur, Taeil; Ko, P

    2011-04-01

    We present a scale invariant extension of the standard model with a new QCD-like strong interaction in the hidden sector. A scale Λ(H) is dynamically generated in the hidden sector by dimensional transmutation, and chiral symmetry breaking occurs in the hidden sector. This scale is transmitted to the SM sector by a real singlet scalar messenger S and can trigger electroweak symmetry breaking. Thus all the mass scales in this model arise from the hidden sector scale Λ(H), which has quantum mechanical origin. Furthermore, the lightest hadrons in the hidden sector are stable by the flavor conservation of the hidden sector strong interaction, and could be the cold dark matter (CDM). We study collider phenomenology, relic density, and direct detection rates of the CDM of this model. PMID:21561182

  6. CHARMMing: A new, flexible, web portal for CHARMM

    PubMed Central

    Miller, Benjamin T.; Singh, Rishi P.; Klauda, Jeffery B.; Hodošček, Milan; Brooks, Bernard R.; Woodcock, H. Lee

    2009-01-01

    A new web portal for the CHARMM macromolecular modeling package, CHARMMing (CHARMM interface and graphics, http://www.charmming.org), is presented. This tool provides a user friendly interface for the preparation, submission, monitoring, and visualization of molecular simulations (i.e., energy minimization, solvation, and dynamics). The infrastructure used to implement the web application is described. Two additional programs have been developed and integrated with CHARMMing: GENRTF, which is employed to define structural features not supported by the standard CHARMM force field, and a job broker, which is used to provide a portable method for using grid and cluster computing with CHARMMing. The use of the program is described with three proteins: 1YJP, 1O1O and 1UFY. Source code is provided allowing CHARMMing to be downloaded, installed, and used by supercomputing centers and research groups that have a CHARMM license. Although no software can replace a scientist’s own judgment and experience, CHARMMing eases the introduction of newcomers to the molecular modeling discipline by providing a graphical method for running simulations. PMID:18698840

  7. Improving data discovery and usability through commentary and user feedback: the CHARMe project

    NASA Astrophysics Data System (ADS)

    Alegre, R.; Blower, J. D.

    2014-12-01

    Earth science datasets are highly diverse. Users of these datasets are similarly varied, ranging from research scientists through industrial users to government decision- and policy-makers. It is very important for these users to understand the applicability of any dataset to their particular problem so that they can select the most appropriate data sources for their needs. Although data providers often provide rich supporting information in the form of metadata, typically this information does not include community usage information that can help other users judge fitness-for-purpose.The CHARMe project (http://www.charme.org.uk) is filling this gap by developing a system for sharing "commentary metadata". These are annotations that are generated and shared by the user community and include: Links between publications and datasets. The CHARMe system can record information about why a particular dataset was used (e.g. the paper may describe the dataset, it may use the dataset as a source, or it may be publishing results of a dataset assessment). These publications may appear in the peer-reviewed literature, or may be technical reports, websites or blog posts. Free-text comments supplied by the user. Provenance information, including links between datasets and descriptions of processing algorithms and sensors. External events that may affect data quality (e.g. large volcanic eruptions or El Niño events); we call these "significant events". Data quality information, e.g. system maturity indices. Commentary information can be linked to anything that can be uniquely identified (e.g. a dataset with a DOI or a persistent web address). It is also possible to associate commentary with particular subsets of datasets, for example to highlight an issue that is confined to a particular geographic region. We will demonstrate tools that show these capabilities in action, showing how users can apply commentary information during data discovery, visualization and analysis. The

  8. Intrinsic charm content of the nucleon and charmness-nucleon sigma term

    NASA Astrophysics Data System (ADS)

    Duan, Shaorong; An, C. S.; Saghai, B.

    2016-06-01

    In the extended chiral constituent quark model, the intrinsic c c ¯ content of the nucleon is investigated. The probabilities of the quark-antiquark components in the nucleon wave functions are calculated by taking the nucleon to be admixtures of three- and five-quark components, with the relevant transitions handled via the 3P0 mechanism. Predictions for the probability of the c c ¯ in the nucleon wave function and the charmness-nucleon sigma term are presented. Our numerical results turn out to be consistent with the predictions from various other approaches reported in the literature.

  9. Terraforming and the coming charm industries

    NASA Astrophysics Data System (ADS)

    Turner, Frederick

    We will only begin to develop a truly spacefaring civilization when it is in our interest to do so. One key issue is what constitutes a human ``interest'' and even more important, how will human interests change during the coming era in which planetary engineering will become feasible. The European exploration of the Americas is a valuable analogy; the true beneficiaries of the Columbian discovery were not the aristocrats, sailors and warriors but the farmers and planters that followed them. If we are to get an accurate picture of the potential wealth to be gained from the solar system, we must recognize the successive waves of economic energy through which our civilization is passing. It is already clear that the shrinkage of employment and investment that occurred in farming is already happening to the extractive and manufacturing sectors and will happen to the information industries and the biotech/nanotech industries that will succeed them. Finally, we will be left with the irreducibly labor- and capital-intensive human industries of what we might call ``charm''. The chief natural resources required for these industries are empty space and empty time, which would be plentiful in the new planetary habitats opened up by terraforming. The paper will explore a few of the practical and visionary possibilities of such a perspective.

  10. Charm CP violation and mixing at Belle

    NASA Astrophysics Data System (ADS)

    Rok Ko, Byeong; Belle Collaboration

    2014-11-01

    We present charm CP violation and mixing measurements at Belle. They are the first observation of D0 - bar D0 mixing in e+e- collisions from D0 → K+π- decays, the most precise mixing and indirect CP violation parameters from D0 → K0Sπ+π- decays, and the timeintegrated CP asymmetries in D0 → π0π0 and D0 → K0Sπ0 decays. Our mixing measurement in D0 → K+π- decays excludes the no-mixing hypothesis at the 5.1 standard deviation level. The mixing parameters x = (0.56 ± 0.19+0.03+0.06-0.09-0.09)%, y = (0.30 ± 0.15+0.04+0.03-0.05-0.06)% and indirect CP violation parameters |q/p| = (0.90+0.16+0.05+0.06-0.15-0.04-0.05)%, arg(q/p) = (-6 ± 11 ± 3+3-4)° measured from D0 → K0Sπ+π- decays, and the time-integrated CP asymmetries AD0→π0π0CP = (-0.03 ± 0.64 ± 0.10)% and AD0→K0Sπ0CP = (-0.21 ± 0.16 ± 0.07)% are the most precisemeasurements to date. Our measurements here are consistent with predictions of the standard model.

  11. Charm physics at Fermilab E791

    SciTech Connect

    Amato, S.; Anjos, J.C.; Bediaga, I.; Costa, I.; de Mello Neto, J.R.T.; de Miranda, J.; Santoro, A.F.S.; Souza, M.H.G.; Blaylock, G.; Burchat, P.R.; Gagnon, P.; Sugano, K.; de Oliveira, A.J.; Santha, A.; Sokoloff, M.D.; Appel, J.A.; Banerjee, S.; Carter, T.; Denisenko, K.; Halling, M.; James, C.; Kwan, S.; Lundberg, B.; Thorne, K.; Burnstein, R.; Kasper, P.A.; Peng, K.C.; Rubin, H.; Summers, D.J.; Aitala, E.M.; Gounder, K.; Rafatian, A.; Reidy, J.J.; Yi, D.; Granite, D.; Nguyen, A.; Reay, N.W.; Reibel, K.; Sidwell, R.; Stanton, N.; Tripathi, A.; Witchey, N.; Purohit, M.V.; Schwartz, A.; Wiener, J.; Almeida, F.M.L.; Ramalho, A.J.; da Silva Carvalho, H.; Ashery, D.; Gerzon, S.; Lichtenstadt, J.; May-Tal-Beck, S.; Trumer, D.; Bracker, S.B.; Astorga, J.; Milburn, R.; Napier, A.; Radeztsky, S.; Sheaff, M.; Darling, C.; Slaughter, J.; Takach, S.; Wolin, E.

    1992-05-26

    Experiment 791 at Fermilab`s Tagged Photon Laboratory has just accumulated a high statistics charm sample by recording 20 billion events on 24000 8mm tapes. A 500 GeV/c {pi}{sup {minus}} beam was used with a fixed target and a magnetic spectrometer which now includes 23 silicon microstrip planes for vertex reconstruction. A new data acquisition system read out 9000 events/sec during the part of the Tevatron cycle that delivered beam. Digitization and readout took 50 {mu}S per event. Data was buffered in eight large FIFO memories to allow continuous event building and continuous tape writing to a wall of 42 Exabytes at 9.6 MB/sec. The 50 terabytes of data buffered to tape is now being filtered on RISC CPUs. Preliminary results show D{sup 0} {yields} K{sup {minus}}{pi}{sup +} and D{sup +} {yields} K{sup {minus}}{pi}{pi}{sup +} decays. Rarer decays will be pursued.

  12. Dark photons from charm mesons at LHCb

    NASA Astrophysics Data System (ADS)

    Ilten, Philip; Thaler, Jesse; Williams, Mike; Xue, Wei

    2015-12-01

    We propose a search for dark photons A' at the LHCb experiment using the charm meson decay D*(2007 )0→D0A'. At nominal luminosity, D*0→D0γ decays will be produced at about 700 kHz within the LHCb acceptance, yielding over 5 trillion such decays during Run 3 of the LHC. Replacing the photon with a kinetically mixed dark photon, LHCb is then sensitive to dark photons that decay as A'→e+e-. We pursue two search strategies in this paper. The displaced strategy takes advantage of the large Lorentz boost of the dark photon and the excellent vertex resolution of LHCb, yielding a nearly background-free search when the A' decay vertex is significantly displaced from the proton-proton primary vertex. The resonant strategy takes advantage of the large event rate for D*0→D0A' and the excellent invariant-mass resolution of LHCb, yielding a background-limited search that nevertheless covers a significant portion of the A' parameter space. Both search strategies rely on the planned upgrade to a triggerless-readout system at LHCb in Run 3, which will permit the identification of low-momentum electron-positron pairs online during data taking. For dark photon masses below about 100 MeV, LHCb can explore nearly all of the dark photon parameter space between existing prompt-A' and beam-dump limits.

  13. Observation of neutrino-induced neutral current charm events

    NASA Astrophysics Data System (ADS)

    Alton, Andrew Knight

    We report results from the analysis of wrong sign muon (WSM) events in deep inelastic nmN and nmN scattering with the NuTeV experiment at the Fermi National Accelerator Laboratory. These measurements are made possible by the high-purity NuTeV sign-selected beams. Using the anti-neutrino mode (WSM) sample we extract the normalizations for all known sources of beam impurities. The corrected charm production at the target measures the cross section, sp+p-->cc using linear atomic mass dependence. Using a boson-gluon fusion model and the neutrino mode WSM sample open neutral current charm production in neutrino scattering has been observed, and the charm mass is determined to be mc=1.40+0.83- 0.36+/-0.2 6 GeV/c2. The average energy of neutrinos which produce a pair of charm quarks is 154 GeV, and at this energy the cross section is sn+N-->cc =(2.14+1.76- 1.54)×10 -1fb . A search for Flavor-Changing Neutral-Current (FCNC) production of bottom and charm has demonstrated a new method of placing limits on FCNC. These limits are of comparable sensitivity to the current best limits, and effectively limit other decay modes.

  14. A high-rate fixed-target charm experiment

    SciTech Connect

    Kaplan, D.M.

    1994-07-01

    In the P865 Letter of Intent, we have proposed a fixed-target experiment aimed at achieving high sensitivity to decays both of charm and of beauty. I describe here a revised version which is somewhat more optimized for charm and less so for beauty. The rationale for this change of emphasis is two-fold: by the time a new fixed-target experiment might run ({approx} Year 2000), it is likely that studies of beauty at the level proposed in P865 win no longer be competitive; furthermore, it may well be that charm is even more interesting than beauty since the background to rare processes beyond the Standard Model is so much smaller in charm than in beauty. At this workshop, Pakvasa has emphasized that rare and forbidden processes such as D{sup o} mixing, charm-changing neutral currents, and lepton-family-violating currents must exist at some level if we are ever to have an understanding of the fermion masses and mixings; some extensions of the Standard Model predict effects detectable at the level of sensitivity discussed here.

  15. E789 and P865: High-rate fixed-target studies of charm and beauty

    SciTech Connect

    Kaplan, D.M.

    1993-06-01

    Experiment 789 at Fermilab used the high-rate E605/E772 spectrometer to study low-multiplicity charm and beauty decays. Preliminary results on charm and beauty production are presented based on analysis of [approx] 100% of the charm data and [approx] 50% of the beauty data. A new experiment is proposed to improve charm and beauty sensitivity by several orders of magnitude.

  16. Hidden symmetries in jammed systems

    NASA Astrophysics Data System (ADS)

    Morse, Peter K.; Corwin, Eric I.

    2016-07-01

    There are deep, but hidden, geometric structures within jammed systems, associated with hidden symmetries. These can be revealed by repeated transformations under which these structures lead to fixed points. These geometric structures can be found in the Voronoi tesselation of space defined by the packing. In this paper we examine two iterative processes: maximum inscribed sphere (MIS) inversion and a real-space coarsening scheme. Under repeated iterations of the MIS inversion process we find invariant systems in which every particle is equal to the maximum inscribed sphere within its Voronoi cell. Using a real-space coarsening scheme we reveal behavior in geometric order parameters which is length-scale invariant.

  17. Economic geology: Hidden gold

    NASA Astrophysics Data System (ADS)

    Richards, Jeremy P.

    2011-02-01

    How the giant sediment-hosted gold deposits of Nevada were formed is disputed. A model linking regional tectonics with magma emplacement and fluid generation at depth suggests that these deposits result from an optimal coincidence of processes.

  18. Multivariate longitudinal data analysis with mixed effects hidden Markov models.

    PubMed

    Raffa, Jesse D; Dubin, Joel A

    2015-09-01

    Multiple longitudinal responses are often collected as a means to capture relevant features of the true outcome of interest, which is often hidden and not directly measurable. We outline an approach which models these multivariate longitudinal responses as generated from a hidden disease process. We propose a class of models which uses a hidden Markov model with separate but correlated random effects between multiple longitudinal responses. This approach was motivated by a smoking cessation clinical trial, where a bivariate longitudinal response involving both a continuous and a binomial response was collected for each participant to monitor smoking behavior. A Bayesian method using Markov chain Monte Carlo is used. Comparison of separate univariate response models to the bivariate response models was undertaken. Our methods are demonstrated on the smoking cessation clinical trial dataset, and properties of our approach are examined through extensive simulation studies. PMID:25761965

  19. Charm Meson Spectroscopy at BaBar and CLEO-C

    SciTech Connect

    Zghiche, A.; /Annecy, LAPP

    2007-10-16

    In this mini-review we report on the most recent progress in charm meson spectroscopy. We discuss the precision measurements performed by the BABAR and CLEO-c experiments in the non strange charm meson part and we present the newly discovered strange charmed meson excited states.

  20. The Hidden Dimensions of Databases.

    ERIC Educational Resources Information Center

    Jacso, Peter

    1994-01-01

    Discusses methods of evaluating commercial online databases and provides examples that illustrate their hidden dimensions. Topics addressed include size, including the number of records or the number of titles; the number of years covered; and the frequency of updates. Comparisons of Readers' Guide Abstracts and Magazine Article Summaries are…

  1. Hidden Costs of School Construction.

    ERIC Educational Resources Information Center

    Glass, Thomas E.

    1999-01-01

    Costs that may increase the original school construction estimates include school-design inefficiency, architect fees, and costs for land, site development, technology, demolition, consultants, and security. A quality-review team can plan to avoid hidden costs and ensure that the new facility will meet instructional needs at the least possible…

  2. Preschoolers Search for Hidden Objects

    ERIC Educational Resources Information Center

    Haddad, Jeffrey M.; Chen, Yuping; Keen, Rachel

    2011-01-01

    The issue of whether young children use spatio-temporal information (e.g., movement of objects through time and space) and/or contact-mechanical information (e.g., interaction between objects) to search for a hidden object was investigated. To determine whether one cue can have priority over the other, a dynamic event that put these cues into…

  3. Sexual Harrassment: A Hidden Problem.

    ERIC Educational Resources Information Center

    Sandler, Bernice R.; And Others

    1981-01-01

    The hidden but serious problem of sexual harassment of students and employees by college faculty is discussed, some statistics are given, and legal and court opinions outlined. Harassment as a violation of Title IX is analyzed, and implications for institutional action to curb it are outlined. (MSE)

  4. D0-D bar 0 mixing and rare charm decays

    SciTech Connect

    Burdman, Gustavo; Shipsey, Ian

    2003-10-08

    We review the current status of flavor-changing neutral currents in the charm sector. We focus on the standard-model predictions and identify the main sources of theoretical uncertainties in both D{sup 0} - {bar D}{sup 0} mixing and rare charm decays. The potential of these observables for constraining short-distance physics in the standard model and its extensions is compromised by the presence of large nonperturbative effects. We examine the possible discovery windows in which short-distance physics can be tested and study the effects of various extensions of the standard model. The current experimental situation and future prospects are reviewed.

  5. The Tau-Charm Factory and tau physics

    SciTech Connect

    Perl, M.L.

    1989-04-01

    An international group of physicists is developing the concept and design of a Tau-Charm Factory: a two-ring, electron-positron, circular collider with 1.5 /< =/ /radical/s /< =/ 4.2 GeV and a design luminosity of 10/sup 33/ cm/sup /minus/2/ s/sup /minus/1/. This paper presents the concept of the facility and outlines the tau lepton physics which can be done. A companion talk by R. Schindler discusses the D/sup 0/, D/sup /+-//, and D/sub s/ physics at a Tau-Charm Factory. 25 refs., 2 tabs.

  6. Towards an understanding of the new charm and charm-strange mesons

    NASA Astrophysics Data System (ADS)

    Godfrey, Stephen

    2005-01-01

    The observation of the DsJ*(2317), DsJ(2460), and SELEX DsJ*(2632) states with properties differing considerably from what was expected has led to a renewed interest in hadron spectroscopy. In addition to these states, non-strange partners of the DsJ states have also been observed. Understanding the D0* and D1' states can provide important insights into the DsJ states. In this contribution I examine quark model predictions for the D0* and D1' states and discuss experimental measurements that can shed light on them. I find that these states are well described as the broad, j = 1/2 non-strange charmed P-wave mesons. In the latter part of this writeup I discuss the cbar s possibilities for the SELEX DsJ*(2632) and measurements that can shed light on it.

  7. Search for popcorn mesons in events with two charmed baryons

    NASA Astrophysics Data System (ADS)

    Hartfiel, Brandon

    The physics of this dissertation is divided into two parts. The first part measures the Λc → pi kp continuum momentum spectrum at a center of mass energy of 10.54 GeV/c, which is just below the Υ(4s) resonance. The data sample consists of 15,400 Λc baryons from 9.46 fb-1 of integrated luminosity collected with the BaBar detector at the PEP-II asymmetric B factory at the Stanford Linear Accelerator Center. With more than 13 times more data than the best previous measurement, we are able to exclude some of the simpler, one parameter fragmentation functions. In the second part, we add the Λc → K0p mode, and look for events with a Λc+ and a Λ c- in order to look for "popcorn" mesons formed between the baryon and antibaryon. We add on-resonance data, with a kinematic cut to eliminate background from B decays, as well as BaBar run 3 and 4 data to increase the total data size to 219.70 fb-1. We find 619 events after background subtraction. After a subtraction of 1.06+/-.09 charged pions coming from decays of known resonances to Λc + npi, we are left with 2.63+/-.21 additional charged pious in each of these events. This is significantly higher than the .5 popcorn mesons per bayon pair used in the current tuning of Pythia 6.2, the most widely used Monte Carlo generator. The extra mesons we find appear to be the first direct evidence of popcorn mesons, although some of them could be arising from hypothetical unresolved, unobserved charmed baryon resonances contributing decay mesons to our data. To contribute a significant fraction, this hypothesis requires a large number of such broad unresolved states and seems unlikely, but can not be completely excluded.

  8. Search for Popcorn Mesons in Events with Two Charmed Baryons

    SciTech Connect

    Hartfiel, Brandon; /SLAC

    2006-07-07

    The physics of this note is divided into two parts. The first part measures the {Lambda}{sub c} {yields} {pi}kp continuum momentum spectrum at a center of mass energy of 10.54 GeV/c. The data sample consists of 15,400 {Lambda}{sub c} baryons from 9.46 fb{sup -1} of integrated luminosity. With more than 13 times more data than the best previous measurement, we are able to exclude some of the simpler, one parameter fragmentation functions. In the second part, we add the {Lambda}{sub c} {yields} K{sup 0}p mode, and look for events with a {Lambda}{sub c}{sup +} and a {bar {Lambda}}{sub c}{sup -} in order to look for ''popcorn'' mesons formed between the baryon and antibaryon. We add on-resonance data, with a kinematic cut to eliminate background from B decays, as well as BaBar run 3 and 4 data to increase the total data size to 219.70 fb{sup -1}. We find 619 events after background subtraction. After a subtraction of 1.06 {+-} .09 charged pions coming from decays of known resonances to {Lambda}{sub c} + {eta}{pi}, we are left with 2.63 {+-} .21 additional charged pions in each of these events. This is significantly higher than the .5 popcorn mesons per baryon pair used in the current tuning of Pythia 6.2, the most widely used Monte Carlo generator. The extra mesons we find appear to be the first direct evidence of popcorn mesons, although some of them could be arising from hypothetical unresolved, unobserved charmed baryon resonances contributing decay mesons to our data. To contribute a significant fraction, this hypothesis requires a large number of such broad unresolved states and seems unlikely, but can not be completely excluded.

  9. Lattice considerations for a tau-charm factory

    SciTech Connect

    Teng, L.C.; Crosbie, E.A.

    1995-06-01

    The magnet lattice appropriate for a tau-charm factory had been studied extensively. Here we discuss two possible simplifying features which make the design, construction, and operation of the machine simpler without sacrificing performance. These two features may be characterized and identified as (a) luminosity optimization in the ``monochromatic`` mode, and (b) chromaticity correction with sextupoles only in the arcs.

  10. Medical treatment and medicinal charms mentioned in the atharvanic literature.

    PubMed

    Bhide, V V

    1981-07-01

    The ancient Vedic texts Provides us with valuable information and guide lines on various multi-faced aspects of human life. The present discussion is limited to the medical treatment and medicinal charms mentioned in the Atharvanic literature with specific consideration to Kausikasutra for better understanding of the rites and actions mentioned in Atharvanaveda. PMID:22556455

  11. Charm and beauty measurements at Fermilab fixed target

    SciTech Connect

    Mishra, C.S.

    1993-10-01

    Eighteen months after a successful run of the Fermilab fixed target program, interesting results from several experiments are available. This is the first time that more than one Fermilab fixed target experiment has reported the observation of beauty mesons. In this paper we review recent results from charm and beauty fixed target experiments at Fermilab.

  12. Role of 'intrinsic charm' in semileptonic B-meson decays

    SciTech Connect

    Breidenbach, C.; Feldmann, T.; Turczyk, S.; Mannel, T.

    2008-07-01

    We discuss the role of so-called 'intrinsic-charm' operators in semileptonic B-meson decays, which appear first at order 1/m{sub b}{sup 3} in the heavy quark expansion. We show by explicit calculation that - at scales {mu}{<=}m{sub c} - the contributions from 'intrinsic-charm' effects can be absorbed into short-distance coefficient functions multiplying, for instance, the Darwin term. Then, the only remnant of 'intrinsic charm' are logarithms of the form ln(m{sub c}{sup 2}/m{sub b}{sup 2}), which can be resummed by using renormalization-group techniques. As long as the dynamics at the charm-quark scale is perturbative, {alpha}{sub s}(m{sub c})<<1, this implies that no additional nonperturbative matrix elements aside from the Darwin and the spin-orbit term have to be introduced at order 1/m{sub b}{sup 3}. Hence, no sources for additional hadronic uncertainties have to be taken into account. Similar arguments may be made for higher orders in the 1/m{sub b} expansion.

  13. Search for a strongly decaying neutral charmed pentaquark

    SciTech Connect

    Link, J.M.; Yager, P.M.; Anjos, J.C.; Bediaga, I.; Castromonte, C.; Machado, A.A.; Magnin, J.; Massafferri, A.; de Miranda, J.M.; Pepe, I.M.; Polycarpo, E.; dos Reis, A.C.; Carrillo, S.; Casimiro, E.; Cuautle, E.; Sanchez-Hernandez, A.; Uribe, C.; Vazquez, F.; Agostino, L.; Cinquini, L.; Cumalat, J.P.; /Colorado U. /Fermilab /Frascati /Guanajuato U. /Illinois U., Urbana /Indiana U. /Korea U. /Kyungpook Natl. U. /INFN, Milan /Milan U. /North Carolina U. /Pavia U. /INFN, Pavia /Rio de Janeiro, Pont. U. Catol. /Puerto Rico U., Mayaguez /South Carolina U. /Tennessee U. /Vanderbilt U. /Wisconsin U., Madison

    2005-06-01

    We present a search for a charmed pentaquark decaying strongly to D{sup (*)}-p. Finding no evidence for such a state, we set limits on the cross section times branching ratio relative to D*{sup -} and D{sup -} under particular assumptions about the production mechanism.

  14. Charm and Charmonium Spectroscopy in BaBar

    SciTech Connect

    Negrini, M.; /Ferrara U.

    2008-02-06

    The BABAR experiment at the PEP-II B-factory offers excellent opportunities in charm and charmonium spectroscopy. The recent observation of new states in the D{sub s} and in the charmonium mass regions revived the interest in this field. Recent BABAR results are presented.

  15. Enhancement of new physics signal sensitivity with mistagged charm quarks

    NASA Astrophysics Data System (ADS)

    Kim, Doojin; Park, Myeonghun

    2016-07-01

    We investigate the potential for enhancing search sensitivity for signals having charm quarks in the final state, using the sizable bottom-mistagging rate for charm quarks at the LHC. Provided that the relevant background processes contain light quarks instead of charm quarks, the application of b-tagging on charm quark-initiated jets enables us to reject more background events than signal ones due to the relatively small mistagging rate for light quarks. The basic idea is tested with two rare top decay processes: i) t → ch → cb b bar and ii) t → bH+ → b b bar c where h and H+ denote the Standard Model-like higgs boson and a charged higgs boson, respectively. The major background source is a hadronic top quark decay such as t → bW+ → b s bar c. We test our method with Monte Carlo simulation at the LHC 14 TeV, and find that the signal-over-background ratio can be increased by a factor of O (6- 7) with a suitably designed (heavy) flavor tagging algorithm and scheme.

  16. Recognition Failure and the Composite Memory Trace in CHARM.

    ERIC Educational Resources Information Center

    Metcalfe, Janet

    1991-01-01

    The relationship between recognition and recall, especially the orderly recognition-failure function relating recognition and the recognizability of recallable words, was investigated using a composite holographic associative recall-recognition memory model (CHARM) in 10 series of computer simulations. Support for the model is demonstrated. (SLD)

  17. Final state interaction for non-leptonic exclusive charm decays

    NASA Astrophysics Data System (ADS)

    Buccella, F.

    2001-12-01

    An approach to the PP and PV exclusive channel for non-leptonic charmed decays, where final state interaction and annihilation contributions play an important role and account for the large SU(3) violations found experimentally, is compared with the most recent and more precise experimental results. The test is particularly successful for the Cabibbo first forbidden rates.

  18. The energy dependence of the total charm cross section

    SciTech Connect

    Vogt, R

    2007-10-18

    We discuss the energy dependence of the total charm cross section and some of its theoretical uncertainties including the quark mass, scale choice and the parton densities. We compare the next-to-leading order calculation of the total cross section with results obtained using PYTHIA.

  19. Unlocking hidden genomic sequence

    PubMed Central

    Keith, Jonathan M.; Cochran, Duncan A. E.; Lala, Gita H.; Adams, Peter; Bryant, Darryn; Mitchelson, Keith R.

    2004-01-01

    Despite the success of conventional Sanger sequencing, significant regions of many genomes still present major obstacles to sequencing. Here we propose a novel approach with the potential to alleviate a wide range of sequencing difficulties. The technique involves extracting target DNA sequence from variants generated by introduction of random mutations. The introduction of mutations does not destroy original sequence information, but distributes it amongst multiple variants. Some of these variants lack problematic features of the target and are more amenable to conventional sequencing. The technique has been successfully demonstrated with mutation levels up to an average 18% base substitution and has been used to read previously intractable poly(A), AT-rich and GC-rich motifs. PMID:14973330

  20. Homodyne impulse radar hidden object locator

    DOEpatents

    McEwan, Thomas E.

    1996-01-01

    An electromagnetic detector is designed to locate an object hidden behind a separator or a cavity within a solid object. The detector includes a PRF generator for generating 2 MHz pulses, a homodyne oscillator for generating a 2 kHz square wave, and for modulating the pulses from the PRF generator. A transmit antenna transmits the modulated pulses through the separator, and a receive antenna receives the signals reflected off the object. The receiver path of the detector includes a sample and hold circuit, an AC coupled amplifier which filters out DC bias level shifts in the sample and hold circuit, and a rectifier circuit connected to the homodyne oscillator and to the AC coupled amplifier, for synchronously rectifying the modulated pulses transmitted over the transmit antenna. The homodyne oscillator modulates the signal from the PRF generator with a continuous wave (CW) signal, and the AC coupled amplifier operates with a passband centered on that CW signal. The present detector can be used in several applications, including the detection of metallic and non-metallic objects, such as pipes, studs, joists, nails, rebars, conduits and electrical wiring, behind wood wall, ceiling, plywood, particle board, dense hardwood, masonry and cement structure. The detector is portable, light weight, simple to use, inexpensive, and has a low power emission which facilitates the compliance with Part 15 of the FCC rules.

  1. Homodyne impulse radar hidden object locator

    DOEpatents

    McEwan, T.E.

    1996-04-30

    An electromagnetic detector is designed to locate an object hidden behind a separator or a cavity within a solid object. The detector includes a PRF generator for generating 2 MHz pulses, a homodyne oscillator for generating a 2 kHz square wave, and for modulating the pulses from the PRF generator. A transmit antenna transmits the modulated pulses through the separator, and a receive antenna receives the signals reflected off the object. The receiver path of the detector includes a sample and hold circuit, an AC coupled amplifier which filters out DC bias level shifts in the sample and hold circuit, and a rectifier circuit connected to the homodyne oscillator and to the AC coupled amplifier, for synchronously rectifying the modulated pulses transmitted over the transmit antenna. The homodyne oscillator modulates the signal from the PRF generator with a continuous wave (CW) signal, and the AC coupled amplifier operates with a passband centered on that CW signal. The present detector can be used in several applications, including the detection of metallic and non-metallic objects, such as pipes, studs, joists, nails, rebars, conduits and electrical wiring, behind wood wall, ceiling, plywood, particle board, dense hardwood, masonry and cement structure. The detector is portable, light weight, simple to use, inexpensive, and has a low power emission which facilitates the compliance with Part 15 of the FCC rules. 15 figs.

  2. Hidden conformal symmetry of extremal black holes

    SciTech Connect

    Chen Bin; Long Jiang; Zhang Jiaju

    2010-11-15

    We study the hidden conformal symmetry of extremal black holes. We introduce a new set of conformal coordinates to write the SL(2,R) generators. We find that the Laplacian of the scalar field in many extremal black holes, including Kerr(-Newman), Reissner-Nordstrom, warped AdS{sub 3}, and null warped black holes, could be written in terms of the SL(2,R) quadratic Casimir. This suggests that there exist dual conformal field theory (CFT) descriptions of these black holes. From the conformal coordinates, the temperatures of the dual CFTs could be read directly. For the extremal black hole, the Hawking temperature is vanishing. Correspondingly, only the left (right) temperature of the dual CFT is nonvanishing, and the excitations of the other sector are suppressed. In the probe limit, we compute the scattering amplitudes of the scalar off the extremal black holes and find perfect agreement with the CFT prediction.

  3. Spectroscopy of doubly and triply-charmed baryons from lattice QCD

    SciTech Connect

    Padmanath, M.; Edwards, Robert G.; Mathur, Nilmani; Peardon, Michael

    2013-11-01

    We present the ground and excited state spectra of doubly and triply-charmed baryons by using lattice QCD with dynamical clover fermions. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6) Ⓧ O(3) symmetry. Various energy splittings between the extracted states, including splittings due to hyperfine as well as spin-orbit coupling, are considered and those are also compared against similar energy splittings at other quark masses. Using those splittings for doubly-charmed baryons, and taking input of experimental Bc meson mass, we predict the mass splittings of B*c-Bc to be about 80 ± 8 MeV and mΩccb=8050±10 MeV.

  4. Compositeness of the strange, charm, and beauty odd parity Λ states

    NASA Astrophysics Data System (ADS)

    Garcia-Recio, C.; Hidalgo-Duque, C.; Nieves, J.; Salcedo, L. L.; Tolos, L.

    2015-08-01

    We study the dependence on the quark mass of the compositeness of the lowest-lying odd parity hyperon states. Thus, we pay attention to Λ -like states in the strange, charm, and beauty sectors which are dynamically generated using a unitarized meson-baryon model. In the strange sector we use a SU(6) extension of the Weinberg-Tomozawa meson-baryon interaction, and we further implement the heavy-quark spin symmetry to construct the meson-baryon interaction when charmed or beauty hadrons are involved. In the three examined flavor sectors, we obtain two JP=1 /2- and one JP=3 /2- Λ states. We find that the Λ states which are bound states (the three Λb) or narrow resonances [one Λ (1405 ) and one Λc(2595 )] are well described as molecular states composed of s -wave meson-baryon pairs. The 1/2- wide Λ (1405 ) and Λc(2595 ) as well as the 3/2- Λ (1520 ) and Λc(2625 ) states display smaller compositeness so they would require new mechanisms, such as d -wave interactions.

  5. Fragment-Based Docking: Development of the CHARMMing Web User Interface as a Platform for Computer-Aided Drug Design

    PubMed Central

    2015-01-01

    Web-based user interfaces to scientific applications are important tools that allow researchers to utilize a broad range of software packages with just an Internet connection and a browser.1 One such interface, CHARMMing (CHARMM interface and graphics), facilitates access to the powerful and widely used molecular software package CHARMM. CHARMMing incorporates tasks such as molecular structure analysis, dynamics, multiscale modeling, and other techniques commonly used by computational life scientists. We have extended CHARMMing’s capabilities to include a fragment-based docking protocol that allows users to perform molecular docking and virtual screening calculations either directly via the CHARMMing Web server or on computing resources using the self-contained job scripts generated via the Web interface. The docking protocol was evaluated by performing a series of “re-dockings” with direct comparison to top commercial docking software. Results of this evaluation showed that CHARMMing’s docking implementation is comparable to many widely used software packages and validates the use of the new CHARMM generalized force field for docking and virtual screening. PMID:25151852

  6. Hidden and generalized conformal symmetry of Kerr-Sen spacetimes

    NASA Astrophysics Data System (ADS)

    Ghezelbash, A. M.; Siahaan, H. M.

    2013-07-01

    It is recently conjectured that generic non-extremal Kerr black hole could be holographically dual to a hidden conformal field theory (CFT) in two dimensions. Moreover, it is known that there are two CFT duals (pictures) to describe the charged rotating black holes which correspond to angular momentum J and electric charge Q of the black hole. Furthermore these two pictures can be incorporated by the CFT duals (general picture) that are generated by SL(2, {Z}) modular group. The general conformal structure can be revealed by looking at charged scalar wave equation in some appropriate values of frequency and charge. In this regard, we consider the wave equation of a charged massless scalar field in the background of Kerr-Sen black hole and show that in the ‘near region’, the wave equation can be reproduced by the Casimir operator of a local SL(2, {R})_L \\times SL(2, {R})_R hidden conformal symmetry. We find the exact agreement between macroscopic and microscopic physical quantities like entropy and absorption cross section of scalars for Kerr-Sen black hole. We then find an extension of vector fields that in turn yields an extended local family of SL(2, {R})_L \\times SL(2, {R})_R hidden conformal symmetry, parameterized by one parameter. For some special values of the parameter, we find a copy of SL(2, {R}) hidden conformal algebra for the charged Gibbons-Maeda-Garfinkle-Horowitz-Strominger black hole in the strong deflection limit.

  7. Higher-dimensional black holes: hidden symmetries and separation of variables

    NASA Astrophysics Data System (ADS)

    Frolov, Valeri P.; Kubizňák, David

    2008-08-01

    In this paper, we discuss hidden symmetries in rotating black hole spacetimes. We start with an extended introduction which mainly summarizes results on hidden symmetries in four dimensions and introduces Killing and Killing Yano tensors, objects responsible for hidden symmetries. We also demonstrate how starting with a principal CKY tensor (that is a closed non-degenerate conformal Killing Yano 2-form) in 4D flat spacetime one can 'generate' the 4D Kerr NUT (A)dS solution and its hidden symmetries. After this we consider higher-dimensional Kerr NUT (A)dS metrics and demonstrate that they possess a principal CKY tensor which allows one to generate the whole tower of Killing Yano and Killing tensors. These symmetries imply complete integrability of geodesic equations and complete separation of variables for the Hamilton Jacobi, Klein Gordon and Dirac equations in the general Kerr NUT (A)dS metrics.

  8. Decaying hidden dark matter in warped compactification

    SciTech Connect

    Chen, Xingang

    2009-09-01

    The recent PAMELA and ATIC/Fermi/HESS experiments have observed an excess of electrons and positrons, but not anti-protons, in the high energy cosmic rays. To explain this result, we construct a decaying hidden dark matter model in string theory compactification that incorporates the following two ingredients, the hidden dark matter scenario in warped compactification and the phenomenological proposal of hidden light particles that decay to the Standard Model. In this model, on higher dimensional warped branes, various warped Kaluza-Klein particles and the zero-mode of gauge field play roles of the hidden dark matter or mediators to the Standard Model.

  9. Quantum computation and hidden variables

    NASA Astrophysics Data System (ADS)

    Aristov, V. V.; Nikulov, A. V.

    2008-03-01

    Many physicists limit oneself to an instrumentalist description of quantum phenomena and ignore the problems of foundation and interpretation of quantum mechanics. This instrumentalist approach results to "specialization barbarism" and mass delusion concerning the problem, how a quantum computer can be made. The idea of quantum computation can be described within the limits of quantum formalism. But in order to understand how this idea can be put into practice one should realize the question: "What could the quantum formalism describe?", in spite of the absence of an universally recognized answer. Only a realization of this question and the undecided problem of quantum foundations allows to see in which quantum systems the superposition and EPR correlation could be expected. Because of the "specialization barbarism" many authors are sure that Bell proved full impossibility of any hidden-variables interpretation. Therefore it is important to emphasize that in reality Bell has restricted to validity limits of the no-hidden-variables proof and has shown that two-state quantum system can be described by hidden variables. The later means that no experimental result obtained on two-state quantum system can prove the existence of superposition and violation of the realism. One should not assume before unambiguous experimental evidence that any two-state quantum system is quantum bit. No experimental evidence of superposition of macroscopically distinct quantum states and of a quantum bit on base of superconductor structure was obtained for the present. Moreover same experimental results can not be described in the limits of the quantum formalism.

  10. Dissipative hidden sector dark matter

    NASA Astrophysics Data System (ADS)

    Foot, R.; Vagnozzi, S.

    2015-01-01

    A simple way of explaining dark matter without modifying known Standard Model physics is to require the existence of a hidden (dark) sector, which interacts with the visible one predominantly via gravity. We consider a hidden sector containing two stable particles charged under an unbroken U (1 )' gauge symmetry, hence featuring dissipative interactions. The massless gauge field associated with this symmetry, the dark photon, can interact via kinetic mixing with the ordinary photon. In fact, such an interaction of strength ε ˜10-9 appears to be necessary in order to explain galactic structure. We calculate the effect of this new physics on big bang nucleosynthesis and its contribution to the relativistic energy density at hydrogen recombination. We then examine the process of dark recombination, during which neutral dark states are formed, which is important for large-scale structure formation. Galactic structure is considered next, focusing on spiral and irregular galaxies. For these galaxies we modeled the dark matter halo (at the current epoch) as a dissipative plasma of dark matter particles, where the energy lost due to dissipation is compensated by the energy produced from ordinary supernovae (the core-collapse energy is transferred to the hidden sector via kinetic mixing induced processes in the supernova core). We find that such a dynamical halo model can reproduce several observed features of disk galaxies, including the cored density profile and the Tully-Fisher relation. We also discuss how elliptical and dwarf spheroidal galaxies could fit into this picture. Finally, these analyses are combined to set bounds on the parameter space of our model, which can serve as a guideline for future experimental searches.

  11. Hidden variables: the resonance factor

    NASA Astrophysics Data System (ADS)

    Brooks, Juliana H. J.

    2009-08-01

    In 1900 Max Karl Planck performed his famous black-body radiation work which sparked the quantum revolution. Re-examination of that work has revealed hidden variables, consistent with Einstein's famous sentiment that quantum mechanics is incomplete due to the existence of "hidden variables". The recent discovery of these previously hidden variables, which have been missing from foundational equations for more than one hundred years, has important implications for theoretical, experimental and applied sciences and technologies. Planck attempted to integrate the new "resonant Hertzian (electromagnetic) waves", with existing Helmholtz theories on energy and thermodynamics. In his famous January 1901, paper on black-body radiation, Planck described two significant hypotheses - his well known Quantum Hypothesis, and his more obscure Resonance Hypothesis. Few scientists today are aware that Planck hypothesized resonant electromagnetic energy as a form of non-thermal energy available to perform work on a molecular basis, and that Planck's Resonance Hypothesis bridged the gap between classical Helmholtz energy state dynamics of the bulk macrostate, and energy state dynamics of the molecular microstate. Since the black-body experimental data involved only a thermal effect and not a resonant effect, Planck excluded the resonant state in his black-body derivation. He calculated Boltzmann's constant "kB" using completely thermal/entropic data, arriving at a value of 1.38 ×10-23 J K-1 per molecule, representing the internal energy of a molecule under completely thermal conditions. He further hypothesized, however, that if resonant energy was present in a system, the resonant energy would be "free to be converted into work". Planck seems to have been caught up in the events of the quantum revolution and never returned to his Resonance Hypothesis. As a result, a mathematical foundation for resonance dynamics was never completed. Boltzmann's constant was adopted into

  12. Unpolarized states and hidden polarization

    NASA Astrophysics Data System (ADS)

    de la Hoz, P.; Björk, G.; Klimov, A. B.; Leuchs, G.; Sánchez-Soto, L. L.

    2014-10-01

    We capitalize on a multipolar expansion of the polarization density matrix, in which multipoles appear as successive moments of the Stokes variables. When all the multipoles up to a given order K vanish, we can properly say that the state is Kth-order unpolarized, as it lacks of polarization information to that order. First-order unpolarized states coincide with the corresponding classical ones, whereas unpolarized to any order tally with the quantum notion of fully invariant states. In between these two extreme cases, there is a rich variety of situations that are explored here. The existence of hidden polarization emerges in a natural way in this context.

  13. Multibunch Instability Investigations for a Tau-Charm Factory

    SciTech Connect

    Zisman, Michael S.

    1989-05-01

    In the design of high-luminosity colliders for high-energy physics, it has become clear that multibunch instabilities will be one of the primary effects that limit beam intensity, and hence luminosity. This paper reports on a series of calculations of multibunch growth rates, using the LBL accelerator physics code ZAP, that illustrate the seriousness of the effect for typical design parameters of a Tau-Charm Factory. A common feature of high-luminosity machines is the requirement of a small beta function at the interaction point. To maintain the advantages of a low beta function, however, requires that the rms bunch length, {sigma}{sub {ell}}, be smaller than {beta}*. This leads, in general, to several inconvenient aspects: (1) The requirement for short bunches leads to the need for a substantial amount of RF hardware-introducing just the narrow-band (high-Q) impedance that generates multibunch instabilities in the first place. (2) The need for short bunches means that bunch lengthening from the longitudinal microwave instability must be avoided. Since the longitudinal impedance Z{sub {parallel}}/n cannot be reduced indefinitely, there is a clear benefit to using many bunches, with lower current per bunch. (3) The short bunches have a Fourier spectrum extending up to very high frequencies, thus effectively sampling impedances in this regime that would be essentially invisible to longer bunches. This aspect can be seen in the exponential cutoff factor, proportional to ({sigma}{sub {ell}/R}){sup 2}, in the expressions for the effective impedance given. In practice, it is difficult to achieve a high luminosity without having a high average beam current in the rings. Because the multibunch growth rates scale linearly with average current, the resulting-rates tend to be very high. It might be imagined that, for sufficient bunch separation and low enough Q values for the higher-order cavity modes, the wake fields have time to die away between successive bunches, thus

  14. Universal approximation of extreme learning machine with adaptive growth of hidden nodes.

    PubMed

    Zhang, Rui; Lan, Yuan; Huang, Guang-Bin; Xu, Zong-Ben

    2012-02-01

    Extreme learning machines (ELMs) have been proposed for generalized single-hidden-layer feedforward networks which need not be neuron-like and perform well in both regression and classification applications. In this brief, we propose an ELM with adaptive growth of hidden nodes (AG-ELM), which provides a new approach for the automated design of networks. Different from other incremental ELMs (I-ELMs) whose existing hidden nodes are frozen when the new hidden nodes are added one by one, in AG-ELM the number of hidden nodes is determined in an adaptive way in the sense that the existing networks may be replaced by newly generated networks which have fewer hidden nodes and better generalization performance. We then prove that such an AG-ELM using Lebesgue p-integrable hidden activation functions can approximate any Lebesgue p-integrable function on a compact input set. Simulation results demonstrate and verify that this new approach can achieve a more compact network architecture than the I-ELM. PMID:24808516

  15. On charm decays: Present status and future goals

    SciTech Connect

    Bigi, I.I.

    1987-06-01

    After a qualitative introduction into the dynamics underlying charm decays the author describes in some detail three different theoretical treatments: the Stech et al. description based on factorization, the 1/N approach and an ansatz employing QCD sum rules. The overall agreement of the emerging theoretical picture with the data is rather encouraging and indicates that the effects of hadronization on these decays are under reasonable control. Yet more and more detailed data are needed to confirm (hopefully) this simple picture. The author lists the processes most relevant in this respect and emphasizes the need for increasing our theoretical sophistication. Once this is achieved we have on one hand acquired the theoretical tools to deal with B physics; on the other hand we will then be ready to exploit charm physics to the fullest in searching for exotic D decays, D/sup 0/ - anti D/sup 0/ mixing and CP violation.

  16. The consideration of Tau-Charm Factory construction in China

    SciTech Connect

    Zhipeng, Zheng

    1994-10-01

    This paper presents a proposal to extend the present Beijing Electron Positron Collider into a Tau Charm Factory. To achieve this aim the author points out that a number of things need to come together, and to be successfully communicated to the Chinese government. Such a machine is a logical extension of the present BEPC device. The physics which can be accomplished at such a device, is important, and cannot be duplicated in planned meson factories, due to the presence of resonances and thresholds which allow minimization of systematic errors. The author stresses the need for international coorperation on this project, to have hope of it coming to fruition. The whole concept of such a Tau Charm Factory needs more support from the high energy physics community.

  17. New results in charm meson spectroscopy from FOCUS and SELEX

    SciTech Connect

    Cooper, Peter S.; /Fermilab

    2005-01-01

    I will review recent results in charmed meson spectroscopy from the Fermilab fixed target charm photo-production and hadro-production experiments, FOCUS and SELEX. FOCUS reports new measurements of the masses and widths of the D*{sub 2}{sup +} and D*{sub 2} mesons, evidence for D*{sub 0}{sup +} and D*{sub 0} broad states and a confirming observation of the D{sub sJ}{sup +}(2317) and other recently observed high mass D{sub sJ}{sup +} states. SELEX has recently reported evidence for a new D{sub sJ}{sup +}(2632) state in both the D{sub s}{sup +} {eta}{sup 0} and D{sup 0}K{sup +} final states.

  18. Polarization effects in double open-charm production at LHCb

    NASA Astrophysics Data System (ADS)

    Echevarría, Miguel G.; Kasemets, Tomas; Mulders, Piet J.; Pisano, Cristian

    2015-04-01

    Double open-charm production is one of the most promising channels to disentangle single from double parton scattering (DPS) and study different properties of DPS. Several studies of the DPS contributions have been made. A missing ingredient so far has been the study of polarization effects, arising from spin correlations between the two partons inside an unpolarized proton. We investigate the impact polarization has on the double open-charm cross section. We show that the longitudinally polarized gluons can give significant contributions to the cross section, but for most of the considered kinematic region only have a moderate effect on the shape. We compare our findings to the LHCb data in the D 0 D 0 final state, identify observables where polarization does have an impact on the distribution of the final state particles, and suggest measurements which could lead to first experimental indications of, or limits on, polarization in DPS.

  19. Fragmentation production of charmed hadrons in electron-positron annihilation

    SciTech Connect

    Novoselov, A. A.

    2010-10-15

    Processes involving the production of D* mesons and {Lambda}{sub c} baryons in electron-positron annihilation at the energies of 10.58 and 91.18 GeV are considered. At the energy of 10.58 GeV, the production of pairs of B mesons that is followed by their decay to charmed particles is analyzed along with direct charm production. The violation of scaling in the respective fragmentation functions is taken into account in the next-to-leading-logarithmic approximation of perturbative QCD. The required nonperturbative fragmentation functions are extracted numerically from experimental data obtained at B factories and are approximated by simple analytic expressions. It is shown that the difference in the nonperturbative fragmentation functions for transitions to mesons and baryons can readily be explained on the basis of the quark-counting rules.

  20. CHARMS: The Cryogenic, High-Accuracy Refraction Measuring System

    NASA Technical Reports Server (NTRS)

    Frey, Bradley; Leviton, Douglas

    2004-01-01

    The success of numerous upcoming NASA infrared (IR) missions will rely critically on accurate knowledge of the IR refractive indices of their constituent optical components at design operating temperatures. To satisfy the demand for such data, we have built a Cryogenic, High-Accuracy Refraction Measuring System (CHARMS), which, for typical 1R materials. can measure the index of refraction accurate to (+ or -) 5 x 10sup -3 . This versatile, one-of-a-kind facility can also measure refractive index over a wide range of wavelengths, from 0.105 um in the far-ultraviolet to 6 um in the IR, and over a wide range of temperatures, from 10 K to 100 degrees C, all with comparable accuracies. We first summarize the technical challenges we faced and engineering solutions we developed during the construction of CHARMS. Next we present our "first light," index of refraction data for fused silica and compare our data to previously published results.

  1. Semileptonic B and Bs decays into orbitally excited charmed mesons

    NASA Astrophysics Data System (ADS)

    Segovia, J.; Albertus, C.; Entem, D. R.; Fernández, F.; Hernández, E.; Pérez-García, M. A.

    2011-11-01

    The BABAR Collaboration has recently reported products of branching fractions that include B meson semileptonic decays into final states with charged and neutral D1(2420) and D2*(2460), two narrow orbitally excited charmed mesons. We evaluate these branching fractions, together with those concerning D0*(2400) and D1'(2430) mesons, within the framework of a constituent quark model. The calculation is performed in two steps, one of which involves a semileptonic decay and the other is mediated by a strong process. Our results are in agreement with the experimental data. We also extend the study to semileptonic decays of Bs into orbitally excited charmed-strange mesons, providing predictions to the possible measurements to be carried out at LHC.

  2. On charm and beauty decays: A theorist's perspective

    SciTech Connect

    Bigi, I.I.

    1987-10-01

    The present understanding of charm and bottom decays is reviewed. Special emphasis is placed on discussing the theoretical uncertainties in view of the particularly rich harvest of new data from the last year. A semi-quantitative description of D decays has emerged enabling us to address rather detailed and relatively subtle questions there, like on once and twice Cabibbo suppressed decays. Beauty physics having left its infancy is now in its adolescence; its future development towards maturity is analyzed.

  3. Combined analysis of charm-quark fragmentation-fraction measurements

    NASA Astrophysics Data System (ADS)

    Lisovyi, Mykhailo; Verbytskyi, Andrii; Zenaiev, Oleksandr

    2016-07-01

    A summary of measurements of the fragmentation of charm quarks into a specific hadron is given. Measurements performed in photoproduction and deep inelastic scattering in e± p, pp and e+e‒ collisions are compared, using up-to-date branching ratios. Within uncertainties, all measurements agree, supporting the hypothesis that fragmentation is independent of the specific production process. Averages of the fragmentation fractions over all measurements are presented. The average has significantly reduced uncertainties compared to individual measurements.

  4. Analysis of charm pair production at the LHC

    NASA Astrophysics Data System (ADS)

    Souza, D.; Brook, N. H.

    2016-01-01

    The Dokshitzer, Gribov, Lipatov, Alterelli, Parisi and Ciafaloni, Catani, Fiorani, Marchesini approaches to perturbative QCD evolution have been investigated by examining correlations of charmed hadron pairs in pp collisions at \\sqrt{s}=7 TeV. The theoretical models are compared to the data taken by the LHCb experiment. Differences in the parton kinematics between the two approaches are discussed. In general a model incorporating next-leading-order diagrams matched to parton showers describes the data best.

  5. Hadron spectroscopy from strangeness to charm and beauty

    NASA Astrophysics Data System (ADS)

    Zou, B. S.

    2013-09-01

    Quarks of different flavors have different masses, which will cause breaking of flavor symmetries of QCD. Flavor symmetries and their breaking in hadron spectroscopy play important role for understanding the internal structures of hadrons. Hadron spectroscopy with strangeness reveals the importance of unquenched quark dynamics. Systematic study of hadron spectroscopy with strange, charm and beauty quarks would be very revealing and essential for understanding the internal structure of hadrons and its underlying quark dynamics.

  6. Charmed Meson Production in 800 GEV Proton-Proton Interactions.

    NASA Astrophysics Data System (ADS)

    Senko, Mark Frederick

    The purpose of this dissertation is to present the results of a study concerning the energy dependence of charmed meson production properties as a test of Quantum Chromodynamics (QCD). This experiment was performed at Fermi National Accelerator Laboratory, using a rapid cycling bubble chamber (LEBC) as a hydrogen target and high resolution vertex detector, in combination with the Fermilab Multiparticle Spectrometer (FMPS). The multiplicity trigger was unbiased, and spectrometer acceptance was good at x_ {F} >=q 0. A comparison of the results from previous experiments at center of mass energies sqrt{s} <=q 27 GeV and sqrt {s} >=q 53 GeV implies a total charm particle production cross section which rises rapidly as a function of sqrt{s} . The result of our experiment, sigma (D/| D) = 42.7 +/- 7.8 mub at sqrt{s} = 38 GeV, indicates a slower rise, in agreement with QCD predictions. A maximum likelihood fit to the parameterization of the differential cross section as d^2sigma/dx_{F}dp _sp{|}{2} ~ (1 - | x_{F }|)^{n}e^{-bp _sp{|}{2}} gives the results n = 8.4_sp {-1.9}{+2.2}, b = 0.78_sp{-0.16}{+0.19} (GeV/c)^{-2}, and < pbot > = 1.1_sp{-0.1}{+0.2} GeV/c. When compared with results from the lower energy experiments, these values indicate charm production becoming more central and < pbot > being consistent with the charmed quark mass. These results are once again consistent with QCD predictions. Lastly, analysis has shown that sigma(D ^*^+/-)/sigma(D^0) is governed primarily by spin statistics, displaying no energy dependence. The resulting cross section for D^*^+/- production is sigma(D^*^+/-) = 13.31 +/- 5.74 mub.

  7. Hadronic decays of beauty and charm from CLEO

    NASA Astrophysics Data System (ADS)

    Rodriguez, Jorge L.

    1999-02-01

    A selection of recent results on hadronic charm and beauty decays from the CLEO experiment are presented. We report preliminary evidence for the existence of final state interactions in B decays and the first observation of the decay B0→D*+D*- with a branching fraction of (7.8-3.8+5.4±1.5)×10-4. We also present preliminary results on the first observation of the broad, JP=1+, charmed meson resonance with a mass of mD1(j=1/2)0=2.461-0.34+0.41±0.010±0.032 GeV and a width of Γ=290-79+101±26±36 MeV and branching fraction measurements of the B-→DJ0π-1 decay. Finally, we report on our search for the radial excitation of a spin 1 charmed meson, the D*'1, and on an improved measurement of the ratio of decay rates Γ(D0→K+π-)/Γ(D0→K-π+).

  8. Constraining the charm Yukawa and Higgs-quark coupling universality

    NASA Astrophysics Data System (ADS)

    Perez, Gilad; Soreq, Yotam; Stamou, Emmanuel; Tobioka, Kohsaku

    2015-08-01

    We introduce four different types of data-driven analyses with different levels of robustness that constrain the size of the Higgs-charm Yukawa coupling: (i) Recasting the vector-boson associated V h analyses that search for the bottom-pair final state. We use this mode to directly and model independently constrain the Higgs-to-charm coupling, yc/ycSM≲234 . (ii) The direct measurement of the total width, yc/ycSM≲120 - 140 . (iii) The search for h →J /ψ γ , yc/ycSM≲220 . (iv) A global fit to the Higgs signal strengths, yc/ycSM≲6.2 . A comparison with t t ¯h data allows us to show that the Higgs does not couple to quarks in a universal way, as is expected in the Standard Model. Finally, we demonstrate how the experimental collaborations can further improve our direct bound by roughly an order of magnitude by charm tagging, as is already used in new-physics searches.

  9. Dissolved gas - the hidden saboteur

    SciTech Connect

    Magorien, V.G.

    1993-12-31

    Almost all hydraulic power components, to properly perform their tasks, rely on one basic, physical property, i.e., the incompressibility of the working fluid. Unfortunately, a frequently overlooked fluid property which frustrates this requirement is its ability to absorb, i.e., dissolve, store and give off gas. The gas is, most often but not always, air. This property is a complex one because it is a function not only of the fluid`s chemical make-up but temperature, pressure, exposed area, depth and time. In its relationshiop to aircraft landing-gear, where energy is absorbed hydraulically, this multi-faceted fluid property can be detrimental in two ways: dynamically, i.e., loss of energy absorption ability and statically, i.e., improper aircraft attitude on the ground. The pupose of this paper is to bring an awareness to this property by presenting: (1) examples of these manifestations with some empirical and practical solutions to them, (2) illustrations of this normally `hidden saboteur` at work, (3) Henry`s Dissolved Gas Law, (4) room-temperature, saturated values of dissolved gas for a number of different working fluids, (5) a description of the instrument used to obtain them, (6) some `missing elements` of the Dissolved Gas Law pertaining to absoption, (7) how static and dynamic conditions effect gas absorption and (8) some recommended solutions to prevent becoming a victim of this `hidden saboteur`

  10. Hidden scale invariance of metals

    NASA Astrophysics Data System (ADS)

    Hummel, Felix; Kresse, Georg; Dyre, Jeppe C.; Pedersen, Ulf R.

    2015-11-01

    Density functional theory (DFT) calculations of 58 liquid elements at their triple point show that most metals exhibit near proportionality between the thermal fluctuations of the virial and the potential energy in the isochoric ensemble. This demonstrates a general "hidden" scale invariance of metals making the condensed part of the thermodynamic phase diagram effectively one dimensional with respect to structure and dynamics. DFT computed density scaling exponents, related to the Grüneisen parameter, are in good agreement with experimental values for the 16 elements where reliable data were available. Hidden scale invariance is demonstrated in detail for magnesium by showing invariance of structure and dynamics. Computed melting curves of period three metals follow curves with invariance (isomorphs). The experimental structure factor of magnesium is predicted by assuming scale invariant inverse power-law (IPL) pair interactions. However, crystal packings of several transition metals (V, Cr, Mn, Fe, Nb, Mo, Ta, W, and Hg), most post-transition metals (Ga, In, Sn, and Tl), and the metalloids Si and Ge cannot be explained by the IPL assumption. The virial-energy correlation coefficients of iron and phosphorous are shown to increase at elevated pressures. Finally, we discuss how scale invariance explains the Grüneisen equation of state and a number of well-known empirical melting and freezing rules.

  11. B, Lambda{sub b} and charm results from the Tevatron

    SciTech Connect

    F. Azfar

    2003-09-18

    Recent results on B{sub d}, B{sub u}{sup {+-}}, B{sub s}, {Lambda}{sub b} and Charm hadrons are reported from {approx} 75 pb{sup -1} and {approx} 40 pb{sup -1} of data accumulated at the upgraded CDF and D0 experiments at the Fermilab Tevatron {bar p}-p collider, during Run-II. These include lifetime and mass measurements of B and Charm hadrons, searches for rare decays in charm and B hadrons and CP-violation in Charm decays. Results relevant to CP-violation in B-decays are also reported.

  12. Measurement of absolute branching fractions of inclusive semileptonic decays of charm and charmed-strange mesons

    SciTech Connect

    Asner, D. M.; Edwards, K. W.; Reed, J.; Robichaud, A. N.; Tatishvili, G.; White, E. J.; Briere, R. A.; Vogel, H.; Onyisi, P. U. E.; Rosner, J. L.; Alexander, J. P.; Cassel, D. G.; Das, S.; Ehrlich, R.; Fields, L.; Gibbons, L.; Gray, S. W.; Hartill, D. L.; Heltsley, B. K.; Hunt, J. M.

    2010-03-01

    We have measured the inclusive semileptonic branching fractions of D{sup 0}, D{sup +}, and D{sub s}{sup +} mesons. For these measurements, we have used the full CLEO-c open-charm data samples, 818 pb{sup -1} at E{sub CM}=3.774 GeV, giving D{sup 0}D{sup 0} and D{sup +}D{sup -} events, and 602 pb{sup -1} at E{sub CM}=4.170 GeV, giving D{sub s}*{sup {+-}D}{sub s}{sup {+-}}events. We obtain B(D{sup 0{yields}}Xe{sup +{nu}}{sub e})=(6.46{+-}0.09{+-}0.11)%, B(D{sup +{yields}}Xe{sup +{nu}}{sub e})=(16.13{+-}0.10{+-}0.29)%, and B(D{sub s}{sup +{yields}}Xe{sup +{nu}}{sub e})=(6.52{+-}0.39{+-}0.15)%, where the first uncertainties are statistical and the second are systematic. From these and lifetimes obtained elsewhere, we obtain the ratios of semileptonic decay widths {Gamma}(D{sup +{yields}}Xe{sup +{nu}}{sub e})/{Gamma}(D{sup 0{yields}}Xe{sup +{nu}}{sub e})=0.985{+-}0.015{+-}0.024 and {Gamma}(D{sub s}{sup +{yields}}Xe{sup +{nu}}{sub e})/{Gamma}(D{sup 0{yields}}Xe{sup +{nu}}{sub e})=0.828{+-}0.051{+-}0.025. The ratio of D{sup +} and D{sup 0} is consistent with the isospin symmetry prediction of unity, and the ratio of D{sub s}{sup +} and D{sup 0} differs from unity, as expected.

  13. Beyond Curriculum Reform: Confronting Medicine's Hidden Curriculum.

    ERIC Educational Resources Information Center

    Hafferty, Frederic W.

    1998-01-01

    Discusses the existence of three curricula in medical schools (formal, informal, and hidden) and suggests that educators and administrators investigate the hidden curriculum by examining four areas: institutional policies; evaluation practices; resource-allocation decisions; and institutional "slang." Needed reforms in accreditation standards are…

  14. Hidden Curriculum in Continuing Medical Education

    ERIC Educational Resources Information Center

    Bennett, Nancy; Lockyer, Jocelyn; Mann, Karen; Batty, Helen; LaForet, Karen; Rethans, Jan-Joost; Silver, Ivan

    2004-01-01

    In developing curricula for undergraduate and graduate medical education, educators have become increasingly aware of an interweaving of the formal, informal, and hidden curricula and their influences on the outcomes of teaching and learning. But, to date, there is little in the literature about the hidden curriculum of medical practice, which…

  15. Hidden Variable Theories and Quantum Nonlocality

    ERIC Educational Resources Information Center

    Boozer, A. D.

    2009-01-01

    We clarify the meaning of Bell's theorem and its implications for the construction of hidden variable theories by considering an example system consisting of two entangled spin-1/2 particles. Using this example, we present a simplified version of Bell's theorem and describe several hidden variable theories that agree with the predictions of…

  16. Building Simple Hidden Markov Models. Classroom Notes

    ERIC Educational Resources Information Center

    Ching, Wai-Ki; Ng, Michael K.

    2004-01-01

    Hidden Markov models (HMMs) are widely used in bioinformatics, speech recognition and many other areas. This note presents HMMs via the framework of classical Markov chain models. A simple example is given to illustrate the model. An estimation method for the transition probabilities of the hidden states is also discussed.

  17. Excited-state spectroscopy of singly, doubly and triply-charmed baryons from lattice QCD

    SciTech Connect

    Padmanath, M.; Edwards, Robert G.; Mathur, Nilmani; Peardon, Michael

    2014-07-01

    We present the ground and excited state spectra of singly, doubly and triply-charmed baryons by using dynamical lattice QCD. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. These operators transform as irreducible representations of SU(3)F symmetry for flavour, SU(4) symmetry for Dirac spins of quarks and O(3) symmetry for orbital angular momenta. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6)ⓍO(3) symmetry.

  18. Towards the quark-gluon plasma Equation of State with dynamical strange and charm quarks

    NASA Astrophysics Data System (ADS)

    Burger, Florian; Ilgenfritz, Ernst-Michael; Lombardo, Maria Paola; Müller-Preussker, Michael; Trunin, Anton

    2016-01-01

    We present an ongoing project aimed at determining the thermodynamic Equation of State (EoS) of quark-gluon matter from lattice QCD with two generations of dynamical quarks. We employ the Wilson twisted mass implementation for the fermionic fields and the improved Iwasaki gauge action. Relying on T = 0 data obtained by the ETM Collaboration the strange and charm quark masses are fixed at their physical values, while the pion mass takes four values in the range from 470 MeV down to 210 MeV. The temperature is varied within a fixed-lattice scale approach. The values for the pseudocritical temperature are obtained from various observables. For the EoS we show preliminary results for the pure gluonic contribution obtained at the pion mass value 370 MeV, where we can compare with previously obtained results with Nf = 2 degenerate light flavours.

  19. Heating up the Galaxy with hidden photons

    SciTech Connect

    Dubovsky, Sergei; Hernández-Chifflet, Guzmán

    2015-12-29

    We elaborate on the dynamics of ionized interstellar medium in the presence of hidden photon dark matter. Our main focus is the ultra-light regime, where the hidden photon mass is smaller than the plasma frequency in the Milky Way. We point out that as a result of the Galactic plasma shielding direct detection of ultra-light photons in this mass range is especially challenging. However, we demonstrate that ultra-light hidden photon dark matter provides a powerful heating source for the ionized interstellar medium. This results in a strong bound on the kinetic mixing between hidden and regular photons all the way down to the hidden photon masses of order 10{sup −20} eV.

  20. Hidden-charm pentaquark state in Λb0→J /ψ p π- decay

    NASA Astrophysics Data System (ADS)

    Wang, En; Chen, Hua-Xing; Geng, Li-Sheng; Li, De-Min; Oset, Eulogio

    2016-05-01

    We study here the Λb0→J /ψ p π- reaction in analogy to the Λb0→J /ψ p K- one, and we note that in both decays there is a sharp structure (dip or peak) in the J /ψ p mass distribution around 4450 MeV, which is associated in the Λb0→J /ψ p K- experiment to an exotic pentaquark baryonic state, although in Λb0→J /ψ p π- it shows up with relatively low statistics. We analyze the Λb0→J /ψ p π- interaction along the same lines as the Λb0→J /ψ p K- one, with the main difference stemming from the reduced Cabibbo strength in the former and the consideration of the π-p final state interaction instead of the K-p one. We find that with a minimal input, introducing the π-p and J /ψ p interaction in S -wave with realistic interactions, and the empirical P -wave and D -wave contributions, one can accomplish a qualitative description of the π-p and J /ψ p mass distributions. More importantly, the peak structure followed by a dip of the experimental J /ψ p mass distribution is reproduced with the same input as used to describe the data of Λb0→J /ψ p K- reaction. The repercussion for the triangular singularity mechanism, invoked in some works to explain the pentaquark peak, is discussed.

  1. Stochastic thermodynamics of hidden pumps

    NASA Astrophysics Data System (ADS)

    Esposito, Massimiliano; Parrondo, Juan M. R.

    2015-05-01

    We show that a reversible pumping mechanism operating between two states of a kinetic network can give rise to Poisson transitions between these two states. An external observer, for whom the pumping mechanism is not accessible, will observe a Markov chain satisfying local detailed balance with an emerging effective force induced by the hidden pump. Due to the reversibility of the pump, the actual entropy production turns out to be lower than the coarse-grained entropy production estimated from the flows and affinities of the resulting Markov chain. Moreover, in presence of a large time scale separation between the fast-pumping dynamics and the slow-network dynamics, a finite current with zero dissipation may be produced. We make use of these general results to build a synthetase-like kinetic scheme able to reversibly produce high free-energy molecules at a finite rate and a rotatory motor achieving 100% efficiency at finite speed.

  2. Stochastic thermodynamics of hidden pumps.

    PubMed

    Esposito, Massimiliano; Parrondo, Juan M R

    2015-05-01

    We show that a reversible pumping mechanism operating between two states of a kinetic network can give rise to Poisson transitions between these two states. An external observer, for whom the pumping mechanism is not accessible, will observe a Markov chain satisfying local detailed balance with an emerging effective force induced by the hidden pump. Due to the reversibility of the pump, the actual entropy production turns out to be lower than the coarse-grained entropy production estimated from the flows and affinities of the resulting Markov chain. Moreover, in presence of a large time scale separation between the fast-pumping dynamics and the slow-network dynamics, a finite current with zero dissipation may be produced. We make use of these general results to build a synthetase-like kinetic scheme able to reversibly produce high free-energy molecules at a finite rate and a rotatory motor achieving 100% efficiency at finite speed. PMID:26066126

  3. Variational Infinite Hidden Conditional Random Fields.

    PubMed

    Bousmalis, Konstantinos; Zafeiriou, Stefanos; Morency, Louis-Philippe; Pantic, Maja; Ghahramani, Zoubin

    2015-09-01

    Hidden conditional random fields (HCRFs) are discriminative latent variable models which have been shown to successfully learn the hidden structure of a given classification problem. An Infinite hidden conditional random field is a hidden conditional random field with a countably infinite number of hidden states, which rids us not only of the necessity to specify a priori a fixed number of hidden states available but also of the problem of overfitting. Markov chain Monte Carlo (MCMC) sampling algorithms are often employed for inference in such models. However, convergence of such algorithms is rather difficult to verify, and as the complexity of the task at hand increases the computational cost of such algorithms often becomes prohibitive. These limitations can be overcome by variational techniques. In this paper, we present a generalized framework for infinite HCRF models, and a novel variational inference approach on a model based on coupled Dirichlet Process Mixtures, the HCRF-DPM. We show that the variational HCRF-DPM is able to converge to a correct number of represented hidden states, and performs as well as the best parametric HCRFs-chosen via cross-validation-for the difficult tasks of recognizing instances of agreement, disagreement, and pain in audiovisual sequences. PMID:26353136

  4. Indirect evidences for existence of exotic mesons in hadronic weak decays of K and charm mesons

    SciTech Connect

    Terasaki, K.

    1998-05-29

    It is demonstrated that hadronic weak decays of K and charm mesons are intimately related to hadron spectroscopy. Long standing puzzles in hadronic weak decays of charm mesons can be solved by taking account of dynamical contributions of various hadrons including non-qq-bar mesons.

  5. The QCD equation of state with charm quarks from lattice QCD

    NASA Astrophysics Data System (ADS)

    Cheng, Michael

    Recently, there have been several calculations of the QCD equation of state (EoS) on the lattice. These calculations take into account the two light quarks and the strange quark, but have ignored the effects of the charm quark, assuming that the charm mass (mc ≈ 1300 MeV) is exponentially suppressed at the temperatures which are explored. However, future heavy ion collisions, such as those planned at the LHC, may well probe temperature regimes where the charm quarks play an important role in the dynamics of the QGP. We present a calculation of the charm quark contribution to the QCD EoS using p4-improved staggered fermions at Nt = 4, 6, 8. This calculation is done with a quenched charm quark, i.e. the relevant operators are measured using a valence charm quark mass on a 2+1 flavor gauge field background. The charm quark masses are determined by calculating charmonium masses (metac and mJ/Psi) and fixing these mesons to their physical masses. The interaction measure, pressure, energy density, and entropy density are calculated. We find that the charm contribution makes a significant contribution, even down to temperatures as low as the pseudo-critical temperature, Tc. However, there are significant scaling corrections at the lattice spacings that we use, preventing a reliable continuum extrapolation.

  6. Excelling at selling: The charming personality style predicts occupational activities, sales performance, and persuasive competence.

    PubMed

    Kazén, Miguel; Kuhl, Julius; Boermans, Sylvie; Koole, Sander L

    2013-08-01

    The present research investigates how individual differences in charming personality are related to occupational activities, sales performance, and persuasive competence. Study 1 showed that sales representatives had higher scores on the charming personality style than executive managers. Study 2 showed that the charming personality style predicted actual sales performance among branch managers of a large German insurance company over a period of 2 years; the explicit power motivation served as a mediator in this relation. Finally, Study 3, carried out in a laboratory setting, confirmed the hypothesis that a charming personality is associated with persuasive competence, which suggests that this style is more relevant for sales representatives than for executive managers. The authors conclude that the charming personality style represents an important psychological resource for organizations. PMID:26271180

  7. In Brief: Hidden environment and health costs of energy

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2009-10-01

    The hidden costs of energy production and use in the United States amounted to an estimated $120 billion in 2005, according to a 19 October report by the U.S. National Research Council. The report, “Hidden Costs of Energy: Unpriced Consequences of Energy Production and Use,” examines hidden costs, including the cost of air pollution damage to human health, which are not reflected in market prices of energy sources, electricity, or gasoline. The report found that in 2005, the total annual external damages from sulfur dioxide, nitrogen oxides, and particulate matter created by coal-burning power plants that produced 95% of the nation's coal-generated electricity were about $62 billion, with nonclimate damages averaging about 3.2 cents for every kilowatt-hour of energy produced. It is estimated that by 2030, nonclimate damages will fall to 1.7 cents per kilowatt-hour. The 2030 figure assumes that new policies already slated for implementation are put in place.

  8. FAIR: a Horizon for Future Charming Physics

    SciTech Connect

    Ritman, James

    2007-11-07

    The science goals underlying the future international Facility for Antiproton and Ion Research--FAIR--[1] that is being realized in Darmstadt span a broad range of research activities on the structure of matter. One component of this facility is directed towards studies of hadronic matter at the sub-nuclear level with beams of antiprotons. These studies focus on two key aspects: confinement of quarks and the generation of the hadron masses. These goals will be pursued by performing precision measurements of charged and neutral decay products from antiproton-proton annihilation in the charmonium mass region. In this talk I present some of the issues connected to FAIR in which the groups in Cracow and Juelich are extending and intensifying our cooperation.

  9. Hidden Staphylococcus aureus Carriage: Overrated or Underappreciated?

    PubMed Central

    2016-01-01

    ABSTRACT Staphylococcus aureus is a persistent companion bacterial species in one-third of humankind. Reservoirs include the nasal and nasopharyngeal cavities, skin, and gastrointestinal (GI) tract. Despite earlier claims that colonization of individuals is caused by clonal organisms, next-generation sequencing (NGS) has revealed that resident type heterogeneity is not exceptional. Carriage, whether overt or hidden, is correlated with a risk of autoinfection. In a recent article in mBio, it was shown that, based on staphylococcal genome sequencing, low-level GI persistence may cause long-term nosocomial outbreaks [L. Senn et al., 7(1):e02039-15, 2016, doi:10.1128/mBio.02039-15]. Institutional endemicity with methicillin-resistant S. aureus (MRSA) sequence type 228 (ST228) is shown to originate not from high-level nasal carriage or poor compliance with infection control practice but from low-grade asymptomatic GI colonization. This shows the power of NGS in elucidating staphylococcal epidemiology and, even more important, demonstrates that (drug-resistant) microorganisms may possess stealthy means of persistence. Identifying these persistence mechanisms is key to successful infection control. PMID:26884429

  10. Stochastic motif extraction using hidden Markov model

    SciTech Connect

    Fujiwara, Yukiko; Asogawa, Minoru; Konagaya, Akihiko

    1994-12-31

    In this paper, we study the application of an HMM (hidden Markov model) to the problem of representing protein sequences by a stochastic motif. A stochastic protein motif represents the small segments of protein sequences that have a certain function or structure. The stochastic motif, represented by an HMM, has conditional probabilities to deal with the stochastic nature of the motif. This HMM directive reflects the characteristics of the motif, such as a protein periodical structure or grouping. In order to obtain the optimal HMM, we developed the {open_quotes}iterative duplication method{close_quotes} for HMM topology learning. It starts from a small fully-connected network and iterates the network generation and parameter optimization until it achieves sufficient discrimination accuracy. Using this method, we obtained an HMM for a leucine zipper motif. Compared to the accuracy of a symbolic pattern representation with accuracy of 14.8 percent, an HMM achieved 79.3 percent in prediction. Additionally, the method can obtain an HMM for various types of zinc finger motifs, and it might separate the mixed data. We demonstrated that this approach is applicable to the validation of the protein databases; a constructed HMM b as indicated that one protein sequence annotated as {open_quotes}lencine-zipper like sequence{close_quotes} in the database is quite different from other leucine-zipper sequences in terms of likelihood, and we found this discrimination is plausible.

  11. Bayesian restoration of a hidden Markov chain with applications to DNA sequencing.

    PubMed

    Churchill, G A; Lazareva, B

    1999-01-01

    Hidden Markov models (HMMs) are a class of stochastic models that have proven to be powerful tools for the analysis of molecular sequence data. A hidden Markov model can be viewed as a black box that generates sequences of observations. The unobservable internal state of the box is stochastic and is determined by a finite state Markov chain. The observable output is stochastic with distribution determined by the state of the hidden Markov chain. We present a Bayesian solution to the problem of restoring the sequence of states visited by the hidden Markov chain from a given sequence of observed outputs. Our approach is based on a Monte Carlo Markov chain algorithm that allows us to draw samples from the full posterior distribution of the hidden Markov chain paths. The problem of estimating the probability of individual paths and the associated Monte Carlo error of these estimates is addressed. The method is illustrated by considering a problem of DNA sequence multiple alignment. The special structure for the hidden Markov model used in the sequence alignment problem is considered in detail. In conclusion, we discuss certain interesting aspects of biological sequence alignments that become accessible through the Bayesian approach to HMM restoration. PMID:10421527

  12. Evidence for a narrow anti-charmed baryon state

    NASA Astrophysics Data System (ADS)

    Aktas, A.; Andreev, V.; Anthonis, T.; Asmone, A.; Babaev, A.; Backovic, S.; Bähr, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Baumgartner, S.; Becker, J.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, Ch.; Berger, N.; Berndt, T.; Bizot, J. C.; Böhme, J.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brisson, V.; Bröker, H.-B.; Brown, D. P.; Bruncko, D.; Büsser, F. W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Caron, S.; Cassol-Brunner, F.; Cerny, K.; Chekelian, V.; Collard, C.; Contreras, J. G.; Coppens, Y. R.; Coughlan, J. A.; Cox, B. E.; Cozzika, G.; Cvach, J.; Dainton, J. B.; Dau, W. D.; Daum, K.; Delcourt, B.; Demirchyan, R.; De Roeck, A.; Desch, K.; De Wolf, E. A.; Diaconu, C.; Dingfelder, J.; Dodonov, V.; Dubak, A.; Duprel, C.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Ellerbrock, M.; Elsen, E.; Erdmann, M.; Erdmann, W.; Faulkner, P. J. W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Fleischer, M.; Fleischmann, P.; Fleming, Y. H.; Flucke, G.; Flügge, G.; Fomenko, A.; Foresti, I.; Formánek, J.; Franke, G.; Frising, G.; Gabathuler, E.; Gabathuler, K.; Garutti, E.; Garvey, J.; Gayler, J.; Gerhards, R.; Gerlich, C.; Ghazaryan, S.; Glazov, A.; Goerlich, L.; Gogitidze, N.; Gorbounov, S.; Grab, C.; Grässler, H.; Greenshaw, T.; Gregori, M.; Grindhammer, G.; Gwilliam, C.; Haidt, D.; Hajduk, L.; Haller, J.; Hansson, M.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Henshaw, O.; Heremans, R.; Herrera, G.; Herynek, I.; Heuer, R.-D.; Hildebrandt, M.; Hiller, K. H.; Höting, P.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jönsson, L.; Johnson, D. P.; Jung, H.; Kant, D.; Kapichine, M.; Karlsson, M.; Katzy, J.; Keller, N.; Kennedy, J.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Koblitz, B.; Korbel, V.; Kostka, P.; Koutouev, R.; Kropivnitskaya, A.; Kroseberg, J.; Kückens, J.; Kuhr, T.; Landon, M. P. J.; Lange, W.; Laštovička, T.; Laycock, P.; Lebedev, A.; Leißner, B.; Lemrani, R.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; List, B.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lueders, H.; Lüke, D.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Mangano, S.; Marage, P.; Marks, J.; Marshall, R.; Martisikova, M.; Martyn, H.-U.; Maxfield, S. J.; Meer, D.; Mehta, A.; Meier, K.; Meyer, A. B.; Meyer, H.; Meyer, J.; Michine, S.; Mikocki, S.; Milcewicz, I.; Milstead, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morozov, I.; Morris, J. V.; Mozer, M. U.; Müller, K.; Murín, P.; Nagovizin, V.; Naroska, B.; Naumann, J.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nikiforov, A.; Nikitin, D.; Nowak, G.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J. E.; Ossoskov, G.; Ozerov, D.; Pascaud, C.; Patel, G. D.; Peez, M.; Perez, E.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Plačakyt≐, R.; Pöschl, R.; Portheault, B.; Povh, B.; Raicevic, N.; Ratiani, Z.; Reimer, P.; Reisert, B.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Rybicki, K.; Sankey, D. P. C.; Sauvan, E.; Schätzel, S.; Scheins, J.; Schilling, F.-P.; Schleper, P.; Schmidt, S.; Schmitt, S.; Schneider, M.; Schoeffel, L.; Schöning, A.; Schröder, V.; Schultz-Coulon, H.-C.; Schwanenberger, C.; Sedlák, K.; Sefkow, F.; Sheviakov, I.; Shtarkov, L. N.; Sirois, Y.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, A.; Spitzer, H.; Stamen, R.; Stella, B.; Stiewe, J.; Strauch, I.; Straumann, U.; Tchoulakov, V.; Thompson, G.; Thompson, P. D.; Tomasz, F.; Traynor, D.; Truöl, P.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Uraev, A.; Urban, M.; Usik, A.; Utkin, D.; Valkár, S.; Valkárová, A.; Vallée, C.; Van Mechelen, P.; Van Remortel, N.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vest, A.; Vinokurova, S.; Volchinski, V.; Wacker, K.; Wagner, J.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Werner, N.; Wessels, M.; Wessling, B.; Winter, G.-G.; Wissing, Ch.; Woehrling, E.-E.; Wolf, R.; Wünsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Žáček, J.; Zálešák, J.; Zhang, Z.; Zhokin, A.; Zohrabyan, H.; Zomer, F.; H1 Collaboration

    2004-05-01

    A narrow resonance in D∗ -p and D∗ +p¯ invariant mass combinations is observed in inelastic electron-proton collisions at centre-of-mass energies of 300 GeV and 320 GeV at HERA. The resonance has a mass of 3099±3(stat.)±5(syst.) MeV and a measured Gaussian width of 12±3(stat.) MeV, compatible with the experimental resolution. The resonance is interpreted as an anti-charmed baryon with a minimal constituent quark composition of uuddc¯, together with the charge conjugate.

  13. Spectroscopy of triply charmed baryons from lattice QCD

    SciTech Connect

    Padmanath, M.; Edwards, Robert G.; Mathur, Nilmani; Peardon, Michael

    2014-10-14

    The spectrum of excitations of triply-charmed baryons is computed using lattice QCD including dynamical light quark fields. The spectrum obtained has baryonic states with well-defined total spin up to 7/2 and the low-lying states closely resemble the expectation from models with an SU(6) x O(3) symmetry. As a result, energy splittings between extracted states, including those due to spin-orbit coupling in the heavy quark limit are computed and compared against data at other quark masses.

  14. Heavy-light charm mesons spectroscopy and decay widths

    NASA Astrophysics Data System (ADS)

    Upadhyay, Alka; Batra, Meenakshi; Gupta, Pallavi

    2016-05-01

    We present the mass formula for heavy-light charm meson at one loop, using heavy quark effective theory. Formulating an effective Lagrangian, the masses of the ground state heavy mesons have been studied in the heavy quark limit, including leading corrections from finite heavy quark masses and nonzero light quark masses, using a constrained fit for the eight equations with 11 parameters including three coupling constants g, h, and g^' }. Masses determined using this approach are fitted to the experimentally known decay widths to estimate the strong coupling constants, showing a better match with available theoretical and experimental data.

  15. Phenomenology of pure-gauge hidden valleys at hadron colliders

    NASA Astrophysics Data System (ADS)

    Juknevich, Jose E.

    Expectations for new physics at the LHC have been greatly influenced by the Hierarchy problem of electroweak symmetry breaking. However, there are reasons to believe that the LHC may still discover new physics, but not directly related to the resolution of the Hierarchy problem. To ensure that such a physics does not go undiscovered requires precise understanding of how new phenomena will reveal themselves in the current and future generation of particle-physics experiments. Given this fact it seems sensible to explore other approaches to this problem; we study three alternatives here. In this thesis I argue for the plausibility that the standard model is coupled, through new massive charged or colored particles, to a hidden sector whose low energy dynamics is controlled by a pure Yang-Mills theory, with no light matter. Such a sector would have numerous metastable "hidden glueballs" built from the hidden gluons. These states would decay to particles of the standard model. I consider the phenomenology of this scenario, and find formulas for the lifetimes and branching ratios of the most important of these states. The dominant decays are to two standard model gauge bosons or to fermion-antifermion pairs, or by radiative decays with photon or Higgs emission, leading to jet- and photon-rich signals, and some occasional leptons. The presence of effective operators of different mass dimensions, often competing with each other, together with a great diversity of states, leads to a great variability in the lifetimes and decay modes of the hidden glueballs. I find that most of the operators considered in this work are not heavily constrained by precision electroweak physics, therefore leaving plenty of room in the parameter space to be explored by the future experiments at the LHC. Finally, I discuss several issues on the phenomenology of the new massive particles as well as an outlook for experimental searches.

  16. Fibroid Tumors in Women: A Hidden Epidemic?

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues Fibroid Tumors in Women: A Hidden Epidemic? Past Issues / ... risk for a woman to develop tumors." Got Fibroids? Volunteers Wanted: Sisters Who Have (Or Have Had) ...

  17. Perspective: Disclosing hidden sources of funding.

    PubMed

    Resnik, David B

    2009-09-01

    In this article, the author discusses ethical and policy issues related to the disclosure of hidden sources of funding in research. The author argues that authors have an ethical obligation to disclose hidden sources of funding and that journals should adopt policies to enforce this obligation. Journal policies should require disclosure of hidden sources of funding that authors know about and that have a direct relation to their research. To stimulate this discussion, the author describes a recent case: investigators who conducted a lung cancer screening study had received funding from a private foundation that was supported by a tobacco company, but they did not disclose this relationship to the journal. Investigators and journal editors must be prepared to deal with these issues in a manner that promotes honesty, transparency, fairness, and accountability in research. The development of well-defined, reasonable policies pertaining to hidden sources of funding can be a step in this direction. PMID:19707061

  18. Charmed baryon strong decays in a chiral quark model

    SciTech Connect

    Zhong Xianhui; Zhao Qiang

    2008-04-01

    Charmed baryon strong decays are studied in a chiral quark model. The data for the decays of {lambda}{sub c}{sup +}(2593), {lambda}{sub c}{sup +}(2625), {sigma}{sub c}{sup ++,+,0}, and {sigma}{sub c}{sup +,0}(2520) are accounted for successfully, which allows one to fix the pseudoscalar-meson-quark couplings in an effective chiral Lagrangian. Extending this framework to analyze the strong decays of the newly observed charmed baryons, we classify that {lambda}{sub c}(2880) and {lambda}{sub c}(2940) as D-wave states in the N=2 shell; {lambda}{sub c}(2880) could be |{lambda}{sub c}{sup 2}D{sub {lambda}}{sub {lambda}}(3/2){sup +}> and {lambda}{sub c}(2940) could be |{lambda}{sub c}{sup 2}D{sub {lambda}}{sub {lambda}}(5/2){sup +}>. Our calculation also suggests that {lambda}{sub c}(2765) is very likely a {rho}-mode P-wave excited state in the N=1 shell, and favors a |{lambda}{sub c}{sup 4}P{sub {rho}}(1/2){sup -}> configuration. The {sigma}{sub c}(2800) favors being a |{sigma}{sub c}{sup 2}P{sub {lambda}}(1/2){sup -}> state. But its being |{sigma}{sub c}{sup ++4}P{sub {lambda}}(5/2){sup -}> cannot be ruled out.

  19. Searches for Rare or Forbidden Semileptonic Charm Decays

    SciTech Connect

    Lees, J.P.

    2011-08-15

    We present searches for rare or forbidden charm decays of the form X{sub c}{sup +} {yields} h{sup {+-}}{ell}{sup {-+}}{ell}{sup ({prime})+}, where X{sub c}{sup +} is a charm hardron (D{sup +}, D{sub s}{sup +}, or {Lambda}{sub c}{sup +}), h{sup {+-}} is a pion, kaon, or proton, and {ell}{sup ({prime}){+-}} is an electron or muon. The analysis is based on 384 fb{sup -1} of e{sup +}e{sup -} annihilation data collected at or close to the {Upsilon}(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the 35 decay modes that are investigated. We establish 90% confidence-level upper limits on the branching fractions between 1 x 10{sup -6} and 44 x 10{sup -6} depending on the channel. In most cases, these results represent either the first limits or significant improvements on existing limits for the decay modes studied.

  20. Charmed-strange meson spectrum: Old and new problems

    NASA Astrophysics Data System (ADS)

    Segovia, Jorge; Entem, David R.; Fernández, Francisco

    2015-05-01

    The LHCb Collaboration has recently reported the observation for the first time of a spin-3 resonance in the heavy quark sector. They have shown that the D¯0K- structure seen in the Bs0→D¯0K-π+ reaction and with invariant mass 2.86 GeV is an admixture of a spin-1 and a spin-3 resonance. Motivated by the good agreement between our theoretical predictions some time ago and the properties extracted from the experiment of the Ds1 *(2860 ) and Ds3 *(2860 ) states, we perform an extension of the study of the strong decay properties of the DsJ *(2860 ) and present the same analysis for the Ds1 *(2700 ) and Ds J(3040 ) mesons. This provides a unified and simultaneous description of the three higher excited charmed-strange resonances observed until now. For completeness, we present theoretical results for masses and strong decays of the low-lying charmed-strange mesons and those experimental missing states which belong to the spin multiplets of the discovered Ds1 *(2700 ), DsJ *(2860 ) and Ds J(3040 ) resonances. The theoretical framework used is a constituent quark model which successfully describes hadron phenomenology from light to heavy quark sectors.

  1. The Experimental Discovery of Double-Charm Baryons

    NASA Astrophysics Data System (ADS)

    Engelfried, Jürgen; Selex Collaboration

    2005-04-01

    In 2002, the SELEX [The SELEX (Fermilab E781) Collaboration: Ball State University, Bogazici University, Carnegie-Mellon University, Centro Brasileiro de Pesquisas Fisicas, Fermilab, Institute For High Energy Physics (Protvino), Institute of High Energy Physics (Beijing), Institute of Theoretical and Experimental Physics (Moscow), Max-Planck-Institute for Nuclear Physics, Moscow State University, Petersburg Nuclear Physics Institute, Tel Aviv University, Universidad Autónoma de San Luis Potosí, Universidade Federal da Paraíba, H. H. Wills Physics Laboratory, University of Bristol, University of Iowa, University of Michigan-Flint, University of Rochester, University of Rome La Sapienza and INFN, University of São Paulo, University of Trieste and INFN. http://www-selex.fnal.gov] Experiment (Fermilab E781) reported the first observation of a member of the family of doubly charmed baryons [SELEX Collaboration, M. Mattson et al.: First observation of the doubly charmed baryonΞcc+. Phys. Rev. Letters 89 (2002) 112001, [ arXiv:hep-ex/0208014

  2. Charmed tetraquarks Tcc and Tcs from dynamical lattice QCD simulations

    NASA Astrophysics Data System (ADS)

    Ikeda, Yoichi; Charron, Bruno; Aoki, Sinya; Doi, Takumi; Hatsuda, Tetsuo; Inoue, Takashi; Ishii, Noriyoshi; Murano, Keiko; Nemura, Hidekatsu; Sasaki, Kenji

    2014-02-01

    Charmed tetraquarks Tcc=(ccubardbar) and Tcs=(csubardbar) are studied through the S-wave meson-meson interactions, D-D, Kbar-D, D-D* and Kbar-D*, on the basis of the (2+1)-flavor lattice QCD simulations with the pion mass mπ≃410, 570 and 700 MeV. For the charm quark, the relativistic heavy quark action is employed to treat its dynamics on the lattice. Using the HAL QCD method, we extract the S-wave potentials in lattice QCD simulations, from which the meson-meson scattering phase shifts are calculated. The phase shifts in the isospin triplet (I=1) channels indicate repulsive interactions, while those in the I=0 channels suggest attraction, growing as mπ decreases. This is particularly prominent in the Tcc (JP=1+,I=0) channel, though neither bound state nor resonance are found in the range mπ=410-700 MeV. We make a qualitative comparison of our results with the phenomenological diquark picture.

  3. Hints for Enhanced b -> sg From Charm and Kaon Counting

    SciTech Connect

    Rathsman, Johan

    2003-05-09

    Previously, motivation for enhanced b {yields} sg from new flavor physics has centered on discrepancies between theory and experiment. Here two experimental hints are considered: (1) updated measurements of the charm multiplicity and {Beta}({bar B} {yields} X{sub c{bar c}s}) at the {Upsilon}(4S) imply {Beta}(B {yields} X{sub no charm}) {approx} 12.4 {+-} 5.6%, (2) the {bar B} {yields} K{sup -}X and {bar B} {yields} K{sup +}/K{sup -}X branching fractions are in excess of conventional {bar B} {yields} X{sub c} {yields} KX yields by about 16.9 {+-} 5.6% and 18 {+-} 5.3%, respectively. JETSET 7.4 was used to estimate kaon yields from s{bar s} popping in {bar B} {yields} X{sub c{bar u}d} decays. JETSET 7.4 Monte Carlos for {Beta}({bar B} {yields} X{sub sg}) {approx} 15% imply that the additional kaon production would lead to 1{sigma} agreement with observed charged and neutral kaon yields. The K{sub s} momentum spectrum would be consistent with recent CLEO bounds in the end point region. Search strategies for enhanced b {yields} sg are discussed in light of large theoretical uncertainty in the standard model fast kaon background from b {yields} s penguin operators.

  4. Why most flavor-dependence predictions for nonleptonic charm decays are wrong: flavor symmetry and final-state interactions in nonleptonic decays of charmed hadrons

    SciTech Connect

    Lipkin, H.J.

    1980-09-01

    Nonleptonic weak decays of strange hadrons are complicated by the interplay of weak and strong interactions. Models based either on symmetry properties or on the selection of certain types of diagrams are both open to criticism. The symmetries used are all broken in strong interactions, and the selection of some diagrams and neglect of others is never seriously justified. Furthermore, the number of related decays of strange hadrons is small, so that experimental data are insufficient for singificant tests of phenomenological models with a few free parameters. The discovery of charmed particles with many open channels for nonleptonic decays has provided a new impetus for a theoretical understanding of these processes. The GIM current provides a well defined weak hamiltonian, which can justifiably be used to first order. The QCD approach to strong interactions gives flavor-indpendent couplings and flavor symmetry broken only by quark masses. In a model with n generations of quarks and 2n flavors, a flavor symmetry group SU(2n) can be defined which is broken only by H/sub weak/ and the quark masses.Here again, the same two approaches by symmetry and dynamics have been used. But both types of treatment tend to consider only the symmetry properties or dominant diagrams of the weak interaction, including some subtle effects, while overlooking rather obvious effects of strong interactions.

  5. AIRWAY LABELING USING A HIDDEN MARKOV TREE MODEL

    PubMed Central

    Ross, James C.; Díaz, Alejandro A.; Okajima, Yuka; Wassermann, Demian; Washko, George R.; Dy, Jennifer; San José Estépar, Raúl

    2014-01-01

    We present a novel airway labeling algorithm based on a Hidden Markov Tree Model (HMTM). We obtain a collection of discrete points along the segmented airway tree using particles sampling [1] and establish topology using Kruskal’s minimum spanning tree algorithm. Following this, our HMTM algorithm probabilistically assigns labels to each point. While alternative methods label airway branches out to the segmental level, we describe a general method and demonstrate its performance out to the subsubsegmental level (two generations further than previously published approaches). We present results on a collection of 25 computed tomography (CT) datasets taken from a Chronic Obstructive Pulmonary Disease (COPD) study. PMID:25436039

  6. Hidden Symmetries of Higher-Dimensional Black Hole Spacetimes

    NASA Astrophysics Data System (ADS)

    Frolov, V. P.

    The paper contains a brief review of recent results onhidden symmetries in higher dimensional black hole spacetimes. We show how the existence of a principal CKY tensor (that is a closed non-degenerate conformal Killing-Yano 2-form) allows one to generate a `tower' of Killing-Yano and Killing tensors responcible for hidden symmetries. These symmetries imply complete integrability of geodesic equations and the complete separation of variables in the Hamilton-Jacobi, Klein-Gordon and Dirac equations in the general Kerr-NUT-(A)dS metrics.

  7. New hidden beauty molecules predicted by the local hidden gauge approach and heavy quark spin symmetry

    NASA Astrophysics Data System (ADS)

    Xiao, C. W.; Ozpineci, A.; Oset, E.

    2015-10-01

    Using a coupled channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-meson interaction with hidden beauty. We obtain several new states of isospin I = 0: six bound states, and weakly bound six more possible states which depend on the influence of the coupled channel effects.

  8. Detection and characterization of regulatory elements using probabilistic conditional random field and hidden Markov models.

    PubMed

    Wang, Hongyan; Zhou, Xiaobo

    2013-04-01

    By altering the electrostatic charge of histones or providing binding sites to protein recognition molecules, Chromatin marks have been proposed to regulate gene expression, a property that has motivated researchers to link these marks to cis-regulatory elements. With the help of next generation sequencing technologies, we can now correlate one specific chromatin mark with regulatory elements (e.g. enhancers or promoters) and also build tools, such as hidden Markov models, to gain insight into mark combinations. However, hidden Markov models have limitation for their character of generative models and assume that a current observation depends only on a current hidden state in the chain. Here, we employed two graphical probabilistic models, namely the linear conditional random field model and multivariate hidden Markov model, to mark gene regions with different states based on recurrent and spatially coherent character of these eight marks. Both models revealed chromatin states that may correspond to enhancers and promoters, transcribed regions, transcriptional elongation, and low-signal regions. We also found that the linear conditional random field model was more effective than the hidden Markov model in recognizing regulatory elements, such as promoter-, enhancer-, and transcriptional elongation-associated regions, which gives us a better choice. PMID:23237214

  9. Automatic Hidden-Web Table Interpretation by Sibling Page Comparison

    NASA Astrophysics Data System (ADS)

    Tao, Cui; Embley, David W.

    The longstanding problem of automatic table interpretation still illudes us. Its solution would not only be an aid to table processing applications such as large volume table conversion, but would also be an aid in solving related problems such as information extraction and semi-structured data management. In this paper, we offer a conceptual modeling solution for the common special case in which so-called sibling pages are available. The sibling pages we consider are pages on the hidden web, commonly generated from underlying databases. We compare them to identify and connect nonvarying components (category labels) and varying components (data values). We tested our solution using more than 2,000 tables in source pages from three different domains—car advertisements, molecular biology, and geopolitical information. Experimental results show that the system can successfully identify sibling tables, generate structure patterns, interpret tables using the generated patterns, and automatically adjust the structure patterns, if necessary, as it processes a sequence of hidden-web pages. For these activities, the system was able to achieve an overall F-measure of 94.5%.

  10. Generations.

    PubMed

    Chambers, David W

    2005-01-01

    Groups naturally promote their strengths and prefer values and rules that give them an identity and an advantage. This shows up as generational tensions across cohorts who share common experiences, including common elders. Dramatic cultural events in America since 1925 can help create an understanding of the differing value structures of the Silents, the Boomers, Gen Xers, and the Millennials. Differences in how these generations see motivation and values, fundamental reality, relations with others, and work are presented, as are some applications of these differences to the dental profession. PMID:16623137