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Related papers: Z -> b b-bar Excess from R-Parity Violation

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The baryon asymmetry of the Universe requires CP violation, but the Standard Model falls short by a factor of $10^{-10}$ or more. Starting from a clue at the $B$ factories, we point out that the large Yukawa couplings of the sequential…

High Energy Physics - Phenomenology · Physics 2008-10-27 Wei-Shu Hou

We study CP violating B decays in the minimal supersymmetric standard model with R-parity violation. We estimate how much R-parity violation modifies the SM predictions for CP asymmetries in B decays within the present bounds. The effects…

High Energy Physics - Phenomenology · Physics 2016-08-25 Ji-Ho Jang , Jae Sik Lee

In the minimal supersymmetric standard model the R-parity violating interactions can trigger various exotic three-body decays for the top quark, which may be accessible at the LHC. In this work we examine the R-violating decays t-> c X_1…

High Energy Physics - Phenomenology · Physics 2009-05-29 Zhaoxia Heng , Gongru Lu , Lei Wu , Jin Min Yang

We study $R$-parity violation in the framework of GUTs, focusing on the case that $R$-parity is broken exclusively through $\Delta B=1$, $\Delta L=0$ effective interactions. We construct two such models, an $SU(5)$ and an $SU(5)\times…

High Energy Physics - Phenomenology · Physics 2016-09-01 K. Tamvakis

CP-violating asymmetries in the processes e+e- -> t tbar and gamma gamma -> ttbar can provide information about CP-violating couplings of the top quark, whose presence would signal physics beyond the standard model. Work on studies of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Saurabh D. Rindani

We explore baryon-number-violating ($|\Delta B| = 2$) processes beyond the well-known neutron-antineutron ($n - \bar{n}$) oscillations, focusing on the $\Lambda - \bar \Lambda$ system. The presence of a strange quark in the $\Lambda$ baryon…

High Energy Physics - Phenomenology · Physics 2025-11-11 Arnau Bas i Beneito , Svjetlana Fajfer , Alexey A. Petrov

Bounds on R-parity violating couplings in the supersymmetric standard model are reviewed, and some new bounds arising from non-observation of certain rare B-decays (such as $B \rightarrow K^+K^-$) are presented. The focus is on…

High Energy Physics - Phenomenology · Physics 2007-05-23 Marc Sher

In minimal supersymmetric standard model the R-parity violating interactions can induce anomalous top pair productions at the LHC through the t-channel process d_R \bar d_R -> t_L \bar t_L by exchanging a slepton or u-channel process d_R…

High Energy Physics - Phenomenology · Physics 2008-11-26 Peiying Li , Gongru Lu , Jin Min Yang , Huanjun Zhang

Recently, it was pointed out that the mixing phase in the Bs-Bsbar system is large, contrary to the expectations in the Standard Model as well as in minimal flavour violation models. The leptonic decay widths of the D_s meson are also found…

High Energy Physics - Phenomenology · Physics 2008-11-26 Anirban Kundu , Soumitra Nandi

In these Lectures we review the Minimal Supersymmetric Standard Model as well as some of its extensions that include R-Parity violation. The cases of spontaneous breaking of R-Parity as well as that of explicit violation through bilinear…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jorge C. Romao

The contribution of the R-parity violating minimal supersymmetric standard model to the neutron beta decay at the one-loop level is investigated. It is found that the baryon number and R-parity violating interactions contribute to the D…

High Energy Physics - Phenomenology · Physics 2012-11-01 Nodoka Yamanaka , Toru Sato , Takahiro Kubota

It has been pointed out recently by Chanowitz that the $Z \to b\bar{b}$ decay asymmetry poses a problem for the standard model whether it is genuine or not [Chanowitz:2001bv]. If this conflict is interpreted as new physics in the b-quark…

High Energy Physics - Phenomenology · Physics 2014-11-17 Xiao-Gang He , G. Valencia

In this article we consider the contribution of $R_p$ violating couplings to the process $e^+e^-(\mu^+\mu^-)\to t{\bar c}$ at high energy lepton collider. We show that the present upper bound on the relevant $R_p$ violating coulpings…

High Energy Physics - Phenomenology · Physics 2009-10-30 Uma Mahanta , Ambar Ghosal

We consider generation of baryon asymmetry of the universe through $R-$parity violation in a scenario in which out-of-equilibrium condition is satisfied by making the electroweak phase transition to be first order. We study all the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Utpal Sarkar , Rathin Adhikari

We obtain analytical formulae for the cross section and the angular distributions of the b(bbar) quarks in the process e+e- -> t tbar, with t -> W+ b (tbar -> W- bbar) assuming CP violation in the \gamma t tbar and Z t tbar vertices. We…

High Energy Physics - Phenomenology · Physics 2016-08-25 A. Bartl , E. Christova , T. Gajdosik , W. Majerotto

We point out that the recent excess observed in searches for a right-handed gauge boson W_R at CMS can be explained in a left-right symmetric model with D parity violation. In a class of SO(10) models, in which D parity is broken at a high…

High Energy Physics - Phenomenology · Physics 2015-06-22 Frank F. Deppisch , Tomas E. Gonzalo , Sudhanwa Patra , Narendra Sahu , Utpal Sarkar

We have derived new upper limits on several products (two at a time) of lepton number violating $\lambda'$-type couplings from the consideration of $\Delta S = 2$ and $\Delta B = 2$ box graphs. Each box contains one scalar lepton and one…

High Energy Physics - Phenomenology · Physics 2008-11-26 Gautam Bhattacharyya , Amitava Raychaudhuri

We calculate contributions to $B_s-\bar{B}_s$ mixing through tree-level sneutrino exchange in the framework of the minimal supersymmetric standard model with R-parity violation, including the next-to-leading-order QCD corrections. We…

High Energy Physics - Phenomenology · Physics 2008-11-26 Xiangdong Gao , Chong Sheng Li , Li Lin Yang

If the b and c quarks mix with new heavy quarks of weak isospin I_3 = -1 and 0 respectively, then the Z -> b b(bar) (c c(bar)) rate is necessarily greater (smaller) than that of the standard model. This may be the reason for the R_b excess…

High Energy Physics - Phenomenology · Physics 2009-12-30 Ernest Ma

Motivated by $-2 \sigma$ deviation from the Standard Model prediction for the forward--backward asymmetry of $Z \to b \bar{b}$ decay in the LEP data, we explore the anomalous couplings of $Z b \bar{b}$ vertex through the electroweak…

High Energy Physics - Phenomenology · Physics 2009-10-31 Kang Young Lee