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Author Gisbert, H.; Pich, A.
Title Direct CP violation in K-0 -> pi pi : Standard Model Status Type Journal Article
Year 2018 Publication Reports on Progress in Physics Abbreviated Journal Rep. Prog. Phys.
Volume 81 Issue 7 Pages 076201 - 22pp
Keywords Kaon decays; CP violation; Standard Model
Abstract In 1988 the NA31 experiment presented the first evidence of direct CP violation in the K-0 -> pi pi decay amplitudes. A clear signal with a 7.2 sigma statistical significance was later established with the full data samples from the NA31, E731, NA48 and KTeV experiments, confirming that CP violation is associated with a Delta S = 1 quark transition, as predicted by the Standard Model. However, the theoretical prediction for the measured ratio epsilon'/epsilon has been a subject of strong controversy along the years. Although the underlying physics was already clarified in 2001, the recent release of improved lattice data has revived again the theoretical debate. We review the current status, discussing in detail the different ingredients that enter into the calculation of this observable and the reasons why seemingly contradictory predictions were obtained in the past by several groups. An update of the Standard Model prediction is presented and the prospects for future improvements are analysed. Taking into account all known short-distance and long-distance contributions, one obtains Re (epsilon' / epsilon) = (15 +/- 7) . 10(-4), in good agreement with the experimental measurement.
Address [Gisbert, Hector; Pich, Antonio] Univ Valencia, CSIC, IFIC, Dept Fis Teor, Apt Correus 22085, E-46071 Valencia, Spain, Email: Antonio.Pich@ific.uv.es
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 (up) Edition
ISSN 0034-4885 ISBN Medium
Area Expedition Conference
Notes WOS:000436545600001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3641
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Author Aguilar, A.C.; Cardona, J.C.; Ferreira, M.N.; Papavassiliou, J.
Title Quark gap equation with non-Abelian Ball-Chiu vertex Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 1 Pages 014002 - 15pp
Keywords
Abstract The full quark-gluon vertex is a crucial ingredient for the dynamical generation of a constituent quark mass from the standard quark gap equation, and its nontransverse part may be determined exactly from the nonlinear Slav nov-Taylor identity that it satisfies. The resulting expression involves not only the quark propagator, but also the ghost dressing function and the quark-ghost kernel, and constitutes the non-abelian extension of the so-called “Ball-Chiu vertex,” known from QED. In the present work we carry out a detailed study of the impact of this vertex on the gap equation and the quark masses generated from it, putting particular emphasis on the contributions directly related with the ghost sector of the theory, and especially the quark-ghost kernel. In particular, we set up and solve the coupled system of six equations that determine the four form factors of the latter kernel and the two typical Dirac structures composing the quark propagator. Due to the incomplete implementation of the multiplicative renormalizability at the level of the gap equation, the correct anomalous dimension of the quark mass is recovered through the inclusion of a certain function, whose ultraviolet behavior is fixed, but its infrared completion is unknown; three particular Ansatze for this function are considered, and their effect on the quark mass and the pion decay constant is explored. The main results of this study indicate that the numerical impact of the quark-ghost kernel is considerable; the transition from a tree-level kernel to the one computed hem leads to a 20% increase in the value of the quark mass at the origin. Particularly interesting is the contribution of the fourth Ball-Chiu form factor, which, contrary to the Abelian case, is nonvanishing, and accounts for 10% of the total constituent quark mass.
Address [Aguilar, A. C.; Cardona, J. C.; Ferreira, M. N.] Univ Campinas UNICAMP, Inst Phys Gleb Wataghin, BR-13083859 Campinas, SP, Brazil
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 (up) Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000436941600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3642
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Author Pavao, R.; Sakai, S.; Oset, E.
Title Production of N*(1535) and N*(1650) in Lambda(c)-> (K)over-bar(0)eta p (pi N) decay Type Journal Article
Year 2018 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 98 Issue 1 Pages 015201 - 8pp
Keywords
Abstract To study the properties of the N*(1535) and N*(1650), we calculate the mass distributions of MB in the Lambda(c) -> (K) over bar (MB)-M-0 decay, with MB = pi N(I = 1/2), eta p, and K Sigma(I = 1/2). We do this by calculating the tree-level and loop contributions, mixing pseudoscalar-baryon and vector-baryon channels using the local hidden gauge formalism. The loop contributions for each channel are calculated using the chiral unitary approach. We observe that for the eta N mass distribution only the N* (1535) is seen, with the N* (1650) contributing to the width of the curve, but for the pi N mass distribution both resonances are clearly visible. In the case of MB = K Sigma, we found that the strength of the K E mass distribution is smaller than that of the mass distributions of the pi N and eta p in the Lambda(+)(c)-> (K) over bar (0)pi N and Lambda(+)(c) -> (K) over bar (0)eta p processes, in spite of this channel having a large coupling to the N* (1650). This is because the K Sigma pair production is suppressed in the primary production from the Lambda(c) decay.
Address [Pavao, R.] Ctr Mixto Univ Valencia, CSIC Inst Invest Paterna, Dept Fis Teor, Valencia 46071, Spain, Email: rpavao@ific.uv.es
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 (up) Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000436940200003 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3643
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Author Liang, W.H.; Oset, E.
Title Pseudoscalar or vector meson production in non-leptonic decays of heavy hadrons Type Journal Article
Year 2018 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 78 Issue 6 Pages 528 - 26pp
Keywords
Abstract We have addressed the study of non-leptonic weak decays of heavy hadrons (Lambda b, Lambda c, B and D), with external and internal emission to give two final hadrons, taking into account the spin-angular momentum structure of the mesons and baryons produced. A detailed angular momentum formulation is developed which leads to easy final formulas. By means of them we have made predictions for a large amount of reactions, up to a global factor, common tomany of them, that we take from some particular data. Comparing the theoretical predictions with the experimental data, the agreement found is quite good in general and the discrepancies should give valuable information on intrinsic form factors, independent of the spin structure studied here. The formulas obtained are also useful in order to evaluate meson-meson or meson-baryon loops, for instance of B decays, in which one has PP, PV, VP or VV intermediate states, with P for pseudoscalar mesons and V for vector meson and lay the grounds for studies of decays into three final particles.
Address [Liang, Wei-Hong] Guangxi Normal Univ, Dept Phys, Guilin 541004, Peoples R China, Email: liangwh@gxnu.edu.cn;
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 (up) Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000437225200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3644
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Author Bhattacharyya, G.; Das, D.; Jay Perez, M.; Saha, I.; Santamaria, A.; Vives, O.
Title Can measurements of 2HDM parameters provide hints for high scale supersymmetry? Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 97 Issue 9 Pages 095018 - 9pp
Keywords
Abstract Two-Higgs-doublet models (2HDMs) arc minimal extensions of the Standard Model (SM) that may still be discovered at the LHC. The quartic couplings of their potentials can be determined from the measurement of the masses and branching ratios of their extended scalar sectors. We show that the evolution of these couplings through renormalization group equations can determine whether the observed 2HDM is a low energy manifestation of a more fundamental theory, as for instance, supersymmetry, which fixes the quartic couplings in terms of the gauge couplings. At leading order, the minimal supersymmetric extension of the SM (MSSM) dictates all the quartic couplings, which can be translated into a predictive structure for the scalar masses and mixings at the weak scale. Running these couplings to higher scales, one can check if they converge to their MSSM values, and more interestingly, whether one can infer the supersymmetry breaking scale. Although we study this question in the context of supersymmetry, this strategy could be applied to any theory whose ultraviolet completion unambiguously predicts all scalar quartic couplings.
Address [Bhattacharyya, Gautam] HBNI, Saha Inst Nucl Phys, 1-AF Bidhan Nagar, Kolkata 700064, India, Email: gautam.bhattacharyya@saha.ac.in;
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 (up) Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000433026000006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3645
Permanent link to this record