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Related papers: U-Spin Tests of the Standard Model and New Physics

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Recent measurements of the time-dependent CP asymmetry of the B -> phi K_S decay give results whose central values differ from standard model expectations. It is shown how such data can be used to identify new physics contributions in a…

High Energy Physics - Phenomenology · Physics 2008-11-26 Cheng-Wei Chiang , Jonathan L. Rosner

We perform a comprehensive study of the impact of new-physics operators with different Lorentz structures on decays involving the b -> s mu+ mu- transition. We examine the effects of new vector-axial vector (VA), scalar-pseudoscalar (SP)…

High Energy Physics - Phenomenology · Physics 2015-05-19 Ashutosh Kumar Alok , Alakabha Datta , Amol Dighe , Murugeswaran Duraisamy , Diptimoy Ghosh , David London

The most sensitive experimental searches for $D-\bar D$ mixing use $D^0 \to K^+ \pi^-$ decays. It is often assumed that effects of New Physics and, in particular, CP violation, can appear through the mixing, while the $c \to d u \bar s$…

High Energy Physics - Phenomenology · Physics 2009-10-31 Sven Bergmann , Yosef Nir

We comment on the implications of the recently measured CP asymmetry in B --> Phi K_S decay. The data disfavor the Standard Model at 2.7 sigma and -if the trend persists in the future with higher statistics - require the existence of CP…

High Energy Physics - Phenomenology · Physics 2009-11-07 Gudrun Hiller

New physics contributions to the $Z$ penguin are revisited in the light of the recently-reported discrepancy of the direct CP violation in $K\to\pi\pi$. Interference effects between the standard model and new physics contributions to…

High Energy Physics - Phenomenology · Physics 2017-05-22 Motoi Endo , Teppei Kitahara , Satoshi Mishima , Kei Yamamoto

The B^0_s -> K^+K^- decay is the U-spin partner of B^0_d -> pi^+\pi^- and allows a determination of the angle gamma of the unitarity triangle of the Cabibbo-Kobayashi-Maskawa matrix. Using updated information on the branching ratio and the…

High Energy Physics - Phenomenology · Physics 2012-04-11 Robert Fleischer , Robert Knegjens

We report measurements of CP violation parameters in $B^0 \to K^0 \pi^0$ decays based on a data sample of $657 \times 10^6 B\bar{B}$ pairs collected with the Belle detector at the KEKB $e^+ e^-$ asymmetric-energy collider. We use $B^0 \to…

High Energy Physics - Experiment · Physics 2019-08-13 M. Fujikawa , Y. Yusa

It is shown that in the approximation of $|\frac{q}{p}|$=1 the CP violation in $B^0_{d,s} \to l^+ l^-$ decays vanishes in SM. In a 2HDM with CP violating phases and MSSM the CP asymmetries depend on the parameters of models and can be as…

High Energy Physics - Phenomenology · Physics 2009-10-31 Chao-Shang Huang , Liao Wei

Based on the low-energy effective Hamiltonian with the generalized factorization, we calculate the new physics contributions to branching ratios and CP-violating asymmetries of the charmless hadronic decays $B_s \to h_1 h_2$ in the standard…

High Energy Physics - Phenomenology · Physics 2009-10-31 Dong Zhang , Zhenjun Xiao , Chong Sheng Li

We update the profile of the CKM matrix. The apex (rhobar,etabar) of the Unitarity Triangle is given by means of a global fit. We propose to include therein sin2alpha from the CP-violating asymmetries in B0->rho+rho-, using isospin to…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Charles , A. Hocker , H. Lacker , S. Laplace , F. R. Le Diberder , J. Malcles , J. Ocariz , M. Pivk , L. Roos

The decay $B^0 \to K^0 \pi^0$, dominated by a $b \to s$ penguin amplitude, holds the potential for exhibiting new physics in this amplitude. In the pure QCD penguin limit one expects $\ckp = 0$ and $\skp = \sin 2 \beta$ for the coefficients…

High Energy Physics - Phenomenology · Physics 2008-11-26 Michael Gronau , Jonathan L. Rosner

In light of the recent experimental data from $B$ factories, We try to explain the large branching ratio (compared to the Standard Model prediction) of the decay $B^{\pm}\to \eta' K^{\pm}$ in the context of R-parity violating ($\rpv$)…

High Energy Physics - Phenomenology · Physics 2009-11-07 B. Dutta , C. S. Kim , Sechul Oh

We consider the impact of R-parity violating suprsymmetry in the nonleptonic decay B --> pi+ pi-. This is one of the rare instances where new physics contributes to both B-Bbar mixing and B --> pi+ pi- decay. We do a numerical analysis to…

High Energy Physics - Phenomenology · Physics 2010-11-23 Gautam Bhattacharyya , Amitava Datta , Anirban Kundu

For any new physics possibly emerging in the future B experiments, the problem is how to extract the signals from the SM background. We consider the decay $b\to s s\bar d$ which is very small in the SM. In the MSSM this decay is possibly…

High Energy Physics - Phenomenology · Physics 2009-10-31 Katri Huitu , Cai-Dian Lü , Paul Singer , Da-Xin Zhang

An isospin analysis of $B\to\pi\pi$ decays yields $\sin 2\alpha$, where $\alpha$ is the usual CKM angle $\alpha\equiv arg [-V_{td}V_{tb}^\ast /(V_{ud}V_{ub}^\ast)]$, without hadronic uncertainty if isospin is a perfect symmetry. Isospin,…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Gardner

The B_s to mu+ mu- decay plays an outstanding role in tests of the Standard Model and physics beyond it. The LHCb collaboration has recently reported the first evidence for this decay at the 3.5 sigma level, with a branching ratio in the…

High Energy Physics - Phenomenology · Physics 2014-12-19 Andrzej J. Buras , Robert Fleischer , Jennifer Girrbach , Robert Knegjens

We discuss the possible existence of new long-range forces mediated by spin-1 or spin-0 particles. By adding their effects to those of gravity, they could lead to apparent violations of the Equivalence Principle. While the vector part in…

High Energy Physics - Phenomenology · Physics 2015-06-25 Pierre Fayet

In radiative B decays to final states containing one spin zero meson, one spin one meson and a photon, the photon polarization can be measured from the angular distribution of the final state. The P-odd, C-even components of this…

High Energy Physics - Phenomenology · Physics 2007-05-23 David Atwood , Tim Gershon , Masashi Hazumi , Amarjit Soni

The decays $B_d\to \pi^+ \pi^-$ and $B_s\to K^+ K^-$ are related to each other by interchanging all down and strange quarks, i.e. through the $U$-spin flavour symmetry of strong interactions. A completely general parametrization of the…

High Energy Physics - Phenomenology · Physics 2010-11-23 Robert Fleischer

The LHCb collaboration has recently reported the first observation of CP violation in the penguin-dominated $B^0_s\to K^-K^+$ decay and further new measurements, indicating differences between the direct CP asymmetries of both the $B^0_s\to…

High Energy Physics - Phenomenology · Physics 2023-03-01 Robert Fleischer , Ruben Jaarsma , K. Keri Vos