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

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The standard-model explanations of the anomalously-large transverse polarization fraction fT in B -> phi K* can be tested by measuring the polarizations of the two decays B+ -> rho+ K*0 and B+ -> rho0 K*+. For the scenario in which the…

High Energy Physics - Phenomenology · Physics 2009-11-11 Seungwon Baek , Alakabha Datta , Philippe Hamel , Oscar F. Hernandez , David London

It is well known that one can use B -> pi pi decays to probe the CP-violating phase \alpha. In this paper we show that these same decays can be used to search for new physics. This is done by comparing two weak phases which are equal in the…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. London , N. Sinha , R. Sinha

Within the Standard Model, the branching fraction of the rare decay $B_s\to K^0\bar K^0$ is related to other decay rates and CP asymmetries through the approximate $SU(3)$ flavor symmetry of the strong interactions and the heavy-quark…

High Energy Physics - Phenomenology · Physics 2025-06-11 Yuval Grossman , Yosef Nir , Matthias Neubert , Yogev Shpilman , Yehonatan Viernik

The LHCb Collaboration has recently found a large CP-violating rate asymmetry in the $b$-baryon decay $\Lambda^0_b \to pK^-\pi^+\pi^-$. This is the first observation of CP violation in baryon processes, opening a new window to test its…

High Energy Physics - Phenomenology · Physics 2025-04-09 Xiao-Gang He , Chia-Wei Liu , Jusak Tandean

We analyse the breaking of U-spin on a group theoretical basis. Due to the simple behaviour of the weak effective hamiltonian under U-spin and the unique structure of the breaking terms such a group theoretical analysis leads to a…

High Energy Physics - Phenomenology · Physics 2009-12-30 Martin Jung , Thomas Mannel

We present an analysis of the rare exclusive $B$ decays $B\to K\nu\bar\nu$ and $B\to K^{*}\nu\bar\nu$ within the Standard Model (SM), in a model-independent manner, and in a number of new physics (NP) models. Combining new form factor…

High Energy Physics - Phenomenology · Physics 2014-12-17 Andrzej J. Buras , Jennifer Girrbach-Noe , Christoph Niehoff , David M. Straub

The measured B -> pi pi, pi K branching ratios exhibit puzzling patterns. We point out that the B -> pi pi hierarchy can be nicely accommodated in the Standard Model (SM) through non-factorizable hadronic interference effects, whereas the B…

High Energy Physics - Phenomenology · Physics 2009-11-10 Andrzej J. Buras , Robert Fleischer , Stefan Recksiegel , Felix Schwab

A model-independent analytical analysis for charmless B decays is presented. It is demonstrated that the CP-averaging branching ratio difference $\Delta R = R_c - R_n$ in $B\to \pi K$ decays with $R_c = 2Br(\pi^0K^-)/Br(\pi^-\bar{K}^0)$ and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yue-Liang Wu , Yu-Feng Zhou , Ci Zhuang

We make a systematic analysis of the effects of new physics in the B decay amplitudes on the CP asymmetries in neutral B decays. Although these are expected to be smaller than new physics effects on the mixing amplitude, they are easier to…

High Energy Physics - Phenomenology · Physics 2016-11-03 Yuval Grossman , Mihir P. Worah

We perform a model independent analysis of new physics in $B^*_s \rightarrow \mu^+ \mu^-$ decay. We intend to identify new physics operator(s) which can provide large enhancement in the branching ratio of $B^*_s \rightarrow \mu^+ \mu^-$…

High Energy Physics - Phenomenology · Physics 2018-02-14 Dinesh Kumar , Jyoti Saini , Shireen Gangal , Sanjeeda Bharati Das

Employing the SU(2) isospin symmetry of strong interactions and estimates borrowed from effective field theory, we explore the impact of new physics on the decays $B^\pm\to \phi K^\pm$ and $B_d\to \phi K_S$ in a model-independent manner. To…

High Energy Physics - Phenomenology · Physics 2010-05-28 Robert Fleischer , Thomas Mannel

We summarize a recent strategy for a global analysis of the B -> pi pi, pi K systems and rare decays. We find that the present B -> pi pi and B -> pi K data cannot be simultaneously described in the Standard Model. In a simple extension in…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrzej J. Buras , Robert Fleischer , Stefan Recksiegel , Felix Schwab

The CP-violating asymmetries in the exclusive decay B->K^*l^+l^- (l=e,mu,tau) are predicted to be exceedingly small in the standard model (SM), thereby offering an opportunity to assess various new-physics scenarios. We derive quantitative…

High Energy Physics - Phenomenology · Physics 2011-03-23 F. Krüger , E. Lunghi

The observation of a sizable direct CP asymmetry in the inclusive decays B -> X_s gamma would be a clean signal of New Physics. In the Standard Model, this asymmetry is below 1% in magnitude. In extensions of the Standard Model with new…

High Energy Physics - Phenomenology · Physics 2007-05-23 Matthias Neubert

In the light of new experimental results on $B \to K\pi$ decays, we study the decay processes $B \to K \pi$ in the framework of both R-parity conserving (SUGRA) and R-parity violating supersymmetric models. We find that any possible…

High Energy Physics - Phenomenology · Physics 2008-11-26 Richard Arnowitt , Bhaskar Dutta , Bo Hu , Sechul Oh

New CP violating physics in $b\to s$ transitions will modify the CP asymmetries in B decays into final CP eigenstates ($\phi K_S$, $\eta^\prime K_S$, $\pi^0 K_S$, $\omega K_S$, $\rho^0 K_S$ and $\eta K_S$) from their Standard Model values.…

High Energy Physics - Phenomenology · Physics 2009-11-11 Gerhard Buchalla , Gudrun Hiller , Yosef Nir , Guy Raz

The observation of a sizable CP asymmetry in the inclusive decays B -> Xs gamma would be a clean signal of New Physics. In the Standard Model, this asymmetry is below 1 % in magnitude. In extensions of the Standard Model with new…

High Energy Physics - Phenomenology · Physics 2009-10-31 Matthias Neubert

A sum rule relation is proposed for direct CP asymmetries in $B\to K\pi$ decays. Leading terms are identical in the isospin symmetry limit, while subleading terms are equal in the flavor SU(3) and heavy quark limits. The sum rule predicts…

High Energy Physics - Phenomenology · Physics 2010-04-05 Michael Gronau

In the presence of large New Physics contributions to loop-induced b->s transitions, sizable direct CP violation in B-> phi K decays is expected on general grounds. We compute explicitly CP-violating effects using QCD factorization and find…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Ciuchini , L. Silvestrini

Over the last two decades, $B \to \pi K$ modes have received a lot of attention. They are particularly interesting since the main contribution to these decays comes from QCD penguin topologies. Furthermore, electroweak penguin amplitudes…

High Energy Physics - Phenomenology · Physics 2018-12-07 Robert Fleischer , Ruben Jaarsma , Eleftheria Malami , K. Keri Vos