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Author (down) 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 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 (down) Romero-Lopez, F.; Rusetsky, A.; Urbach, C.
Title Two- and three-body interactions in phi 4 theory from lattice simulations Type Journal Article
Year 2018 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 78 Issue 10 Pages 846 - 15pp
Keywords
Abstract We calculate the one-, two- and three-particle energy levels for different lattice volumes in the complex phi(4) theory on the lattice. We argue that the exponentially suppressed finite-volume corrections for the two- and three-particle energy shifts can be reduced significantly by using the single particle mass, which includes the finite-size effects. We show numerically that, for a set of bare parameters, corresponding to the weak repulsive interaction, one can reliably extract the two- and three-particle energy shifts. From those, we extract the scattering length, the effective range and the effective three-body coupling. We show that the parameters, extracted from the two- and three-particle energy shifts, are consistent. Moreover, the effective three-body coupling is significantly different from zero.
Address [Romero-Lopez, F.] 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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000448080300003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3778
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Author (down) Romero-Lopez, F.; Rusetsky, A.; Schlage, N.; Urbach, C.
Title Relativistic N-particle energy shift in finite volume Type Journal Article
Year 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 060 - 52pp
Keywords Lattice QCD; Lattice Quantum Field Theory
Abstract We present a general method for deriving the energy shift of an interacting system of N spinless particles in a finite volume. To this end, we use the nonrelativistic effective field theory (NREFT), and match the pertinent low-energy constants to the scattering amplitudes. Relativistic corrections are explicitly included up to a given order in the 1/L expansion. We apply this method to obtain the ground state of N particles, and the first excited state of two and three particles to order L-6 in terms of the threshold parameters of the two- and three-particle relativistic scattering amplitudes. We use these expressions to analyze the N-particle ground state energy shift in the complex phi (4) theory.
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:000617678000002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4711
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Author (down) Hernandez, P.; Romero-Lopez, F.
Title The large N-c limit of QCD on the lattice Type Journal Article
Year 2021 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 57 Issue 2 Pages 52 - 19pp
Keywords
Abstract We review recent progress in the study of the large N-c limit of gauge theories from lattice simulations. The focus is not only the planar limit but also the size of O(N-c(-1)) corrections for values of N-c greater than or similar to 3. Some concrete examples of the topics we include are tests of large- Nc factorization, the topological susceptibility, the glueball, meson and baryon spectra, the chiral dependence of masses and decay constants, and weak matrix elements related to the Delta I = 1/2 rule in kaon decays.
Address [Romero-Lopez, Fernando] Univ Valencia, Inst Fis Corpuscular, Valencia, Spain, Email: m.pilar.hernandez@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 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000617515000003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4718
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Author (down) Hernandez, P.; Pena, C.; Romero-Lopez, F.
Title Large Nc scaling of meson masses and decay constants Type Journal Article
Year 2019 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 79 Issue 10 Pages 865 - 13pp
Keywords
Abstract We perform an ab initio calculation of the Nc scaling of the low-energy couplings of the chiral Lagrangian of low-energy strong interactions, extracted from the mass dependence of meson masses and decay constants. We compute these observables on the lattice with four degenerate fermions, Nf=4, and varying number of colours, Nc=3-6, at a lattice spacing of a similar or equal to 0.075 fm. We find good agreement with the expected Nc scaling and measure the coefficients of the leading and subleading terms in the large Nc expansion. From the subleading Nc corrections, we can also infer the Nf dependence, that we use to extract the value of the low-energy couplings for different values of Nf. We find agreement with previous determinations at Nc=3 and Nf=2,3 and also, our results support a strong paramagnetic suppression of the chiral condensate in moving from Nf=2 to Nf=3.
Address [Hernandez, P.; Romero-Lopez, F.] IFIC CSIC UVEG, Edificio Inst Invest,Apt 22085, Valencia 46071, 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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000492031700002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4186
Permanent link to this record