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Author Li, X.Q.; Li, Y.M.; Lu, G.R.; Su, F.
Title B-s(0)-(B)over-bar(s)(0) mixing in a family non-universal Z ' model revisited Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 05 Issue 5 Pages 049 - 27pp
Keywords Beyond Standard Model; B-Physics; CP violation
Abstract Motivated by the very recent measurements performed at the LHCb and the Tevatron of the B-s(0) – (B) over bar (0)(s) mixing, in this paper we revisit it in a family non-universal Z' model, to check if a simultaneous explanation for all the mixing observables, especially for the like-sign dimuon charge asymmetry observed by the D0 collaboration, could be made in such a specific model. In the first scenario where the Z' boson contributes only to the off-diagonal element M-12(s), it is found that, once the combined constraints from Delta M-s, phi(s) and Delta Gamma(s) are imposed, the model could not explain the measured flavour-specific CP asymmetry a(fs)(s), at least within its 1 sigma ranges. In the second scenario where the NP contributes also to the absorptive part Gamma(s)(12) via tree-level Z'-induced b -> c (c) over bars operators, we find that, with the constraints from Delta M-s, phi(s) and the indirect CP asymmetry in (B) over bar (d) -> J/psi K-S taken into account, the present measured 1 sigma experimental ranges for a(fs)(s) could not be reproduced too. Thus, such a specific Z' model with our specific assumptions could not simultaneously reconcile all the present data on B-s(0) – B-s(0) mixing. Future improved measurements from the LHCb and the proposed superB experiments, especially of the flavour-specific CP asymmetries, are expected to shed light on the issue.
Address [Li, Xin-Qiang; Li, Yan-Min; Lu, Gong-Ru] Henan Normal Univ, Dept Phys, Xinxiang 453007, Henan, Peoples R China, Email: xqli@itp.ac.cn;
Corporate Author Thesis
Publisher (up) Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000305236000049 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1103
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Author Jung, M.; Li, X.Q.; Pich, A.
Title Exclusive radiative B-meson decays within the aligned two-Higgs-doublet model Type Journal Article
Year 2012 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 063 - 33pp
Keywords Higgs Physics; Beyond Standard Model; B-Physics; CP violation
Abstract In the aligned two-Higgs-doublet model, the alignment of Yukawa matrices in flavour space guarantees the absence of tree-level flavour-changing neutral currents, while allowing at the same time for new sources of CP violation, implying potentially large effects in many low-energy processes. In this work we study the constraints from exclusive radiative B -> V gamma decays, where V denotes a light vector meson. The current experimental data on the CP-averaged branching ratios and the direct CP and isospin asymmetries are analyzed. It is found that, while the branching ratios and direct CP asymmetries do not constrain the parameter space much further compared to the inclusive B -> X-s,X-d gamma decays, complementary constraints can be obtained from the isospin asymmetries Delta(K*gamma) and Delta(rho gamma). In addition, correlations between the various observables in exclusive B -> V gamma and inclusive B -> X-s,X-d gamma decays are investigated in detail, and predictions are made for several so far unmeasured observables.
Address [Jung, Martin] Tech Univ Dortmund, Inst Phys, D-44221 Dortmund, Germany, Email: martin2.jung@tu-dortmund.de;
Corporate Author Thesis
Publisher (up) Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000310851800004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1293
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Author Celis, A.; Jung, M.; Li, X.Q.; Pich, A.
Title Sensitivity to charged scalars in B -> D-(*)tau nu(tau) and B -> tau nu(tau) decays Type Journal Article
Year 2013 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 054 - 27pp
Keywords Beyond Standard Model; B-Physics
Abstract We analyze the recent experimental evidence for an excess of tau-lepton production in several exclusive semileptonic B-meson decays in the context of two-Higgs-doublet models. These decay modes are sensitive to the exchange of charged scalars and constrain strongly their Yukawa interactions. While the usual Type-II scenario cannot accommodate the recent BaBar data, this is possible within more general models in which the charged-scalar couplings to up-type quarks are not as suppressed. Both the B -> D-(*)tau nu(tau) and the B -> tau nu(tau) data can be fitted within the framework of the Aligned Two-Higgs-Doublet Model, but the resulting parameter ranges are in conflict with the constraints from leptonic charm decays. This could indicate a departure from the family universality of the Yukawa couplings, beyond their characteristic fermion mass dependence. We discuss several new observables that are sensitive to a hypothetical charged-scalar contribution, demonstrating that they are well suited to distinguish between different scenarios of new physics in the scalar sector, and also between this group and models with different Dirac structures; their experimental study would therefore shed light on the relevance of scalar exchanges in semileptonic b -> c tau(-)(nu) over bar (tau) transitions.
Address [Celis, Alejandro; Li, Xin-Qiang; Pich, Antonio] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: alejandro.celis@ific.uv.es;
Corporate Author Thesis
Publisher (up) Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1126-6708 ISBN Medium
Area Expedition Conference
Notes WOS:000315583200054 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1368
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Author Li, X.Q.; Lu, J.; Pich, A.
Title Bs,d(0) -> l(+)l(-) decays in the aligned two-Higgs-doublet model Type Journal Article
Year 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 022 - 39pp
Keywords Higgs Physics; Rare Decays; Beyond Standard Model; B-Physics
Abstract The rare decays B-s,d(0) -> l(+)l(-) are analyzed within the general framework of the aligned two-Higgs doublet model. We present a complete one-loop calculation of the relevant short-distance Wilson coefficients, giving a detailed technical summary of our results and comparing them with previous calculations performed in particular limits or approximations. We investigate the impact of various model parameters on the branching ratios and study the phenomenological constraints imposed by present data.
Address [Li, Xin-Qiang] Cent China Normal Univ, Inst Particle Phys, Wuhan 430079, Hubei, Peoples R China, Email: xqli@itp.ac.cn;
Corporate Author Thesis
Publisher (up) 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:000338520600002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1855
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Author Abbas, G.; Celis, A.; Li, X.Q.; Lu, J.; Pich, A.
Title Flavour-changing top decays in the aligned two-Higgs-doublet model Type Journal Article
Year 2015 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 06 Issue 6 Pages 005 - 26pp
Keywords Rare Decays; Beyond Standard Model; Heavy Quark Physics
Abstract We perform a complete one-loop computation of the two-body flavour-changing top decays t --> ch and t --> cV (V = gamma, Z), within the aligned two-Higgs-doublet model. We evaluate the impact of the model parameters on the associated branching ratios, taking into account constraints from flavour data and measurements of the Higgs properties. Assuming that the 125 GeV Higgs corresponds to the lightest CP-even scalar of the CP-conserving aligned two-Higgs-doublet model, we find that the rates for such flavour-changing top decays lie below the expected sensitivity of the future high-luminosity phase of the LHC. Measurements of the Higgs signal strength in the di-photon channel are found to play an important role in limiting the size of the t --> ch decay rate when the charged scalar of the model is light.
Address [Abbas, Gauhar; Pich, Antonio] Univ Valencia, CSIC, IFIC, E-46071 Valencia, Spain, Email: Gauhar.Abbas@ific.uv.es;
Corporate Author Thesis
Publisher (up) 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:000355745800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2255
Permanent link to this record