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Author Donini, A.; Hernandez, P.; Pena, C.; Romero-Lopez, F.
Title Nonleptonic kaon decays at large N-c Type Journal Article
Year 2016 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 94 Issue 11 Pages 114511 - 6pp
Keywords (up)
Abstract We study the scaling with the number of colors, N-c, of the weak amplitudes mediating kaon mixing and decay. We evaluate the amplitudes of the two relevant current-current operators on the lattice for N-c = 3-7. We conclude that the subleading 1/N-c corrections in B-k, are small, but those in the K -> pi pi amplitudes are large and fully anticoirelated in the I = 0, 2 isospin channels. We briefly comment on the implications for the Delta I = 1/2 rule.
Address [Donini, A.; Hernandez, P.; Romero-Lopez, F.] IFIC CSIC UVEG, Edificio Inst Invest,Apt 22085, E-46071 Valencia, Spain
Corporate Author Thesis
Publisher Amer 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 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000390275100007 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2894
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Author 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 (up)
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 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 (up)
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
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Author Blanton, T.D.; Romero-Lopez, F.; Sharpe, S.R.
Title I=3 Three-Pion Scattering Amplitude from Lattice QCD Type Journal Article
Year 2020 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 124 Issue 3 Pages 032001 - 7pp
Keywords (up)
Abstract We analyze the spectrum of two- and three-pion states of maximal isospin obtained recently for isosymmetric QCD with pion mass M approximate to 200 MeV in Horz and Hanlon, [Phys. Rev. Lett. 123, 142002 (2019)]. Using the relativistic three-particle quantization condition, we find similar to 2 sigma evidence for a nonzero value for the contact part of the 3 pi(+) (I = 3) scattering amplitude. We also compare our results to leading-order chiral perturbation theory. We find good agreement at threshold and some tension in the energy dependent part of the 3 pi(+) scattering amplitude. We also find that the 2 pi(+) (I = 2) spectrum is fit well by an s-wave phase shift that incorporates the expected Adler zero.
Address [Blanton, Tyler D.; Sharpe, Stephen R.] Univ Washington, Phys Dept, Seattle, WA 98195 USA, Email: blanton1@uw.edu;
Corporate Author Thesis
Publisher Amer 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 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000509506000002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4264
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Author Donini, A.; Hernandez, P.; Pena, C.; Romero-Lopez, F.
Title Dissecting the Delta I=1/2 rule at large N-c Type Journal Article
Year 2020 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 80 Issue 7 Pages 638 - 12pp
Keywords (up)
Abstract We study the scaling of kaon decay amplitudes with the number of colours, N-c, in a theory with four degenerate flavours, N-f = 4. In this scenario, two current-current operators, Q(+/-), mediate Delta S = 1 transitions, such as the two isospin amplitudes of non-leptonic kaon decays for K -> (pi pi)(I=0,2), A(0) and A(2.) In particular, we concentrate on the simpler K -> pi amplitudes, A(+/-), mediated by these two operators. A diagrammatic analysis of the large-N-c scaling of these observables is presented, which demonstrates the anticorrelation of the leading O(1/N-c) and O(N-f/N-c(2)) corrections in both amplitudes. Using our new N-f = 4 and previous quenched data, we confirm this expectation and show that these corrections are naturally large and may be at the origin of the Delta I = 1/2 rule. The evidence for the latter is indirect, based on the matching of the amplitudes to their prediction in Chiral Perturbation Theory, from which the LO low-energy couplings of the chiral weak Hamiltonian, g(+/-), can be determined. A NLO estimate of the K -> (pi pi)(I=0,2) isospin amplitudes can then be derived, which is in good agreement with the experimental value.
Address [Donini, Andrea; Hernandez, Pilar; Romero-Lopez, Fernando] 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:000552393200003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4480
Permanent link to this record