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Author Hansen, M.T.; Romero-Lopez, F.; Sharpe, S.R.
Title Generalizing the relativistic quantization condition to include all three-pion isospin channels Type Journal Article
Year (down) 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue 7 Pages 047 - 49pp
Keywords Lattice QCD; Scattering Amplitudes
Abstract We present a generalization of the relativistic, finite-volume, three-particle quantization condition for non-identical pions in isosymmetric QCD. The resulting formalism allows one to use discrete finite-volume energies, determined using lattice QCD, to constrain scattering amplitudes for all possible values of two- and three-pion isospin. As for the case of identical pions considered previously, the result splits into two steps: the first defines a non-perturbative function with roots equal to the allowed energies, E-n(L), in a given cubic volume with side-length L. This function depends on an intermediate three-body quantity, denoted K-df;3, which can thus be constrained from lattice QCD input. The second step is a set of integral equations relating K-df,K-3 to the physical scattering amplitude, M-3. Both of the key relations, E-n(L) <-> K-df,K-3 and K-df,K-3 <-> M-3, are shown to be block-diagonal in the basis of definite three-pion isospin, I-pi pi pi, so that one in fact recovers four independent relations, corresponding to I-pi pi pi = 0; 1; 2; 3. We also provide the generalized threshold expansion of K-df,K-3 for all channels, as well as parameterizations for all three-pion resonances present for I-pi pi pi = 0 and I-pi pi pi = 1. As an example of the utility of the generalized formalism, we present a toy implementation of the quantization condition for I-pi pi pi = 0, focusing on the quantum numbers of the omega and h(1) resonances.
Address [Hansen, Maxwell T.] Univ Geneva, Theoret Phys Dept, CH-1211 Geneva 23, Switzerland, Email: maxwell.hansen@cern.ch;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000551981200002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4474
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Author Molina, R.; Ruiz de Elvira, J.
Title Light- and strange-quark mass dependence of the rho(770) meson revisited Type Journal Article
Year (down) 2020 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 11 Issue 11 Pages 017 - 74pp
Keywords Chiral Lagrangians; Lattice QCD
Abstract Recent lattice data on pi pi -scattering phase shifts in the vector-isovector channel, pseudoscalar meson masses and decay constants for strange-quark masses smaller or equal to the physical value allow us to study the strangeness dependence of these observables for the first time. We perform a global analysis on two kind of lattice trajectories depending on whether the sum of quark masses or the strange-quark mass is kept fixed to the physical point. The quark mass dependence of these observables is extracted from unitarized coupled-channel one-loop Chiral Perturbation Theory. This analysis guides new predictions on the rho (770) meson properties over trajectories where the strange-quark mass is lighter than the physical mass, as well as on the SU(3) symmetric line. As a result, the light- and strange-quark mass dependence of the rho (770) meson parameters are discussed and precise values of the Low Energy Constants present in unitarized one-loop Chiral Perturbation Theory are given. Finally, the current discrepancy between two- and three-flavor lattice results for the rho (770) meson is studied.
Address [Molina, R.] Ctr Mixto Univ Valencia CSIC, Dept Fis Teor, Inst Invest Paterna, Aptdo 22085, Valencia 46071, Spain, Email: raqumoli@ucm.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000591048300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4615
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Author Blanton, T.D.; Romero-Lopez, F.; Sharpe, S.R.
Title Implementing the three-particle quantization condition including higher partial waves Type Journal Article
Year (down) 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages 106 - 56pp
Keywords Lattice QCD; Lattice Quantum Field Theory; Scattering Amplitudes
Abstract We present an implementation of the relativistic three-particle quantization condition including both s- and d-wave two-particle channels. For this, we develop a systematic expansion of the three-particle K matrix, K-df,K-3, about threshold, which is the generalization of the effective range expansion of the two-particle K matrix, K-2. Relativistic invariance plays an important role in this expansion. We find that d-wave two-particle channels enter first at quadratic order. We explain how to implement the resulting multichannel quantization condition, and present several examples of its application. We derive the leading dependence of the threshold three-particle state on the two-particle d-wave scattering amplitude, and use this to test our implementation. We show how strong two-particle d-wave interactions can lead to significant effects on the finite-volume three-particle spectrum, including the possibility of a generalized three-particle Efimov-like bound state. We also explore the application to the 3 pi(+) system, which is accessible to lattice QCD simulations, where we study the sensitivity of the spectrum to the components of K-df,K-3. Finally, we investigate the circumstances under which the quantization condition has unphysical solutions.
Address [Blanton, Tyler D.; Sharpe, Stephen R.] Univ Washington, Dept Phys, 3910 15th Ave NE, Seattle, WA 98195 USA, Email: blanton1@uw.edu;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000462325900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3953
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Author Romero-Lopez, F.; Sharpe, S.R.; Blanton, T.D.; Briceno, R.A.; Hansen, M.T.
Title Numerical exploration of three relativistic particles in a finite volume including two-particle resonances and bound states Type Journal Article
Year (down) 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 007 - 43pp
Keywords Lattice QCD; Scattering Amplitudes
Abstract In this work, we use an extension of the quantization condition, given in ref. [1], to numerically explore the finite-volume spectrum of three relativistic particles, in the case that two-particle subsets are either resonant or bound. The original form of the relativistic three-particle quantization condition was derived under a technical assumption on the two-particle K matrix that required the absence of two-particle bound states or narrow two-particle resonances. Here we describe how this restriction can be lifted in a simple way using the freedom in the definition of the K-matrix-like quantity that enters the quantization condition. With this in hand, we extend previous numerical studies of the quantization condition to explore the finite-volume signature for a variety of two- and three-particle interactions. We determine the spectrum for parameters such that the system contains both dimers (two-particle bound states) and one or more trimers (in which all three particles are bound), and also for cases where the two-particle subchannel is resonant. We also show how the quantization condition provides a tool for determining infinite-volume dimer-particle scattering amplitudes for energies below the dimer breakup. We illustrate this for a series of examples, including one that parallels physical deuteron-nucleon scattering. All calculations presented here are restricted to the case of three identical scalar particles.
Address [Romero-Lopez, Fernando] Univ Valencia, CSIC, IFIC, Paterna 46980, Spain, Email: fernando.romero@uv.es;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000497979000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4207
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Author Ren, X.L.; Alvarez-Ruso, L.; Geng, L.S.; Ledwig, T.; Meng, J.; Vicente Vacas, M.J.
Title Consistency between SU(3) and SU(2) covariant baryon chiral perturbation theory for the nucleon mass Type Journal Article
Year (down) 2017 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 766 Issue Pages 325-333
Keywords Baryon chiral perturbation theory; Lattice QCD; Nucleon mass and sigma term
Abstract Treating the strange quark mass as a heavy scale compared to the light quark mass, we perform a matching of the nucleon mass in the SU(3) sector to the two-flavor case in covariant baryon chiral perturbation theory. The validity of the 19low-energy constants appearing in the octet baryon masses up to next-to-next-to-next-to-leading order[1] is supported by comparing the effective parameters (the combinations of the 19couplings) with the corresponding low-energy constants in the SU(2) sector[2]. In addition, it is shown that the dependence of the effective parameters and the pion-nucleon sigma term on the strange quark mass is relatively weak around its physical value, thus providing support to the assumption made in Ref.[2] that the SU(2) baryon chiral perturbation theory can be applied to study n(f) = 2 + 1lattice QCD simulations as long as the strange quark mass is close to its physical value.
Address [Ren, Xiu-Lei; Geng, Li-Sheng; Meng, Jie] Beihang Univ, Sch Phys & Nucl Energy Engn, Beijing 100191, Peoples R China, Email: lisheng.geng@buaa.edu.cn
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000396438300043 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3003
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Author Zhou, B.; Sun, Z.F.; Liu, X.; Zhu, S.L.
Title Chiral corrections to the 1(-+) exotic meson mass Type Journal Article
Year (down) 2017 Publication Chinese Physics C Abbreviated Journal Chin. Phys. C
Volume 41 Issue 4 Pages 043101 - 12pp
Keywords exotic mesons; hybrid state; lattice QCD
Abstract We first construct the effective chiral Lagrangians for the 1(-+) exotic mesons. With the infrared regularization scheme, we derive the one-loop infrared singular chiral corrections to the pi(1) (1600) mass explicitly. We investigate the variation of the different chiral corrections with the pion mass under two schemes. Hopefully, the explicit non-analytical chiral structures will be helpful for the chiral extrapolation of lattice data from the dynamical lattice QCD simulation of either the exotic light hybrid meson or the tetraquark state.
Address [Zhou, Bin] Peking Univ, Dept Phys, Beijing 100871, Peoples R China, Email: binzhou@pku.edu.cn;
Corporate Author Thesis
Publisher Chinese Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1674-1137 ISBN Medium
Area Expedition Conference
Notes WOS:000400124800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3106
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Author Ayala, C.; Cvetic, G.; Kogerler, R.
Title Lattice-motivated holomorphic nearly perturbative QCD Type Journal Article
Year (down) 2017 Publication Journal of Physics G Abbreviated Journal J. Phys. G
Volume 44 Issue 7 Pages 075001 - 30pp
Keywords perturbative QCD; lattice QCD; QCD phenomenology; resummation
Abstract Newer lattice results indicate that, in the Landau gauge at low spacelike momenta, the gluon propagator and the ghost dressing function are finite non-zero. This leads to a definition of the QCD running coupling, in a specific scheme, that goes to zero at low spacelike momenta. We construct a running coupling which fulfills these conditions, and at the same time reproduces to a high precision the perturbative behavior at high momenta. The coupling is constructed in such a way that it reflects qualitatively correctly the holomorphic (analytic) behavior of spacelike observables in the complex plane of the squared momenta, as dictated by the general principles of quantum field theories. Further, we require the coupling to reproduce correctly the nonstrange semihadronic decay rate of tau lepton which is the best measured low-momentum QCD observable with small higher-twist effects. Subsequent application of the Borel sum rules to the V + A spectral functions of tau lepton decays, as measured by OPAL Collaboration, determines the values of the gluon condensate and of the V + A six-dimensional condensate, and reproduces the data to a significantly higher precision than the usual (MS) over bar running coupling.
Address [Ayala, Cesar] Univ Valencia, Dept Theoret Phys, E-46100 Valencia, Spain, Email: Gorazd.Cvetic@usm.cl
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0954-3899 ISBN Medium
Area Expedition Conference
Notes WOS:000402509800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3167
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Author Martinez Torres, A.; Oset, E.; Prelovsek, S.; Ramos, A.
Title Reanalysis of lattice QCD spectra leading to the Ds0*(2317) and Ds1*(2460) Type Journal Article
Year (down) 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 153 - 22pp
Keywords Lattice QCD; Phenomenological Models; QCD
Abstract We perform a reanalysis of the energy levels obtained in a recent lattice QCD simulation, from where the existence of bound states of KD and KD* are induced and identified with the narrow D-s0*(2317) and D-s1*(2460) resonances. The reanalysis is done in terms of an auxiliary potential, employing a single-channel basis KD(*()), and a two-channel basis KD(*()), eta D-s(()*()). By means of an extended Luscher method we determine poles of the continuum t-matrix, bound by about 40 MeV with respect to the KD and KD* thresholds, which we identify with the D-s0*(2317) and D-s1*(2460) resonances. Using a sum rule that reformulates Weinberg compositeness condition we can determine that the state D-s0*(2317) contains a KD component in an amount of about 70%, while the state D-s1*(2460) contains a similar amount of KD*. We argue that the present lattice simulation results do not still allow us to determine which are the missing channels in the bound state wave functions and we discuss the necessary information that can lead to answer this question.
Address [Martinez Torres, A.] Univ Sao Paulo, Inst Fis, BR-05389970 Sao Paulo, SP, Brazil, Email: amartine@if.usp.br;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000355346500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2258
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Author Bernardoni, F.; Blossier, B.; Bulava, J.; Della Morte, M.; Fritzsch, P.; Garron, N.; Gerardin, A.; Heitger, J.; von Hippel, G.; Simma, H.; Sommer, R.
Title The b-quark mass from non-perturbative N-f=2 Heavy Quark Effective Theory at O(1/m(h)) Type Journal Article
Year (down) 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 730 Issue Pages 171-177
Keywords Lattice QCD; Heavy Quark Effective Theory; b-quark mass
Abstract We report our final estimate of the b-quark mass from N-f = 2 lattice QCD simulations using Heavy Quark Effective Theory non-perturbatively matched to QCD at O(1/m(h)). Treating systematic and statistical errors in a conservative manner, we obtain (m) over bar ((MS) over bar)(b) (2 GeV) = 4.88(15) GeV after an extrapolation to the physical point.
Address [Bernardoni, Fabio; Simma, Hubert; Sommer, Rainer] DESY, NIC, D-15738 Zeuthen, Germany
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000333506400031 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1742
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Author Bernardoni, F.; Blossier, B.; Bulava, J.; Della Morte, M.; Fritzsch, P.; Garron, N.; Gerardin, A.; Heitger, J.; von Hippel, G.; Simma, H.; Sommer, R.
Title Decay constants of B-mesons from non-perturbative HQET with two light dynamical quarks Type Journal Article
Year (down) 2014 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 735 Issue Pages 349-356
Keywords Lattice QCD; Heavy Quark Effective Theory; Bottom quarks; Meson decay
Abstract We present a computation of B-meson decay constants from lattice QCD simulations within the framework of Heavy Quark Effective Theory for the b-quark. The next-to-leading order corrections in the HQET expansion are included non-perturbatively. Based on N-f = 2 gauge field ensembles, covering three lattice spacings a approximate to (0.08-0.05) fm and pion masses down to 190 MeV, a variational method for extracting hadronic matrix elements is used to keep systematic errors under control. In addition we perform a careful autocorrelation analysis in the extrapolation to the continuum and to the physical pion mass limits. Our final results read f(B) = 186(13) MeV, f(Bs) = 224(14) MeV and f(Bs)/f(B) = 1.203(65). A comparison with other results in the literature does not reveal a dependence on the number of dynamical quarks, and effects from truncating HQET appear to be negligible.
Address [Bernardoni, Fabio; Simma, Hubert; Sommer, Rainer] NIC DESY, D-15738 Zeuthen, Germany
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000340048900061 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1881
Permanent link to this record