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Related papers: $t\rightarrow \gamma$ decay in the ACD model

200 papers

We compute the partial width of the FCNC top quark decay t->c h in the framework of the Minimal Supersymmetric Standard Model, where h = h0, H0, A0 is any of the neutral Higgs of the MSSM. We include the SUSY electroweak, Higgs, and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jaume Guasch

We study the CP asymmetries of the rare top-quark decays $t \to c \gamma$ and $t \to cg$ in the aligned two-Higgs-doublet model (A2HDM), which is generically characterized by new sources of CP violation beyond the Standard Model (SM).…

High Energy Physics - Phenomenology · Physics 2025-03-17 Fang-Min Cai , Rui-Lin Fan , Xin-Qiang Li , Ya-Dong Yang

We present standard model (SM) estimates for exclusive $c \to u \gamma$ processes in heavy quark and hybrid frameworks. Measured branching ratios ${\cal{B}}(D^0 \to (\phi, \bar K^{*0}) \gamma)$ are at or somewhat exceeding the upper range…

High Energy Physics - Phenomenology · Physics 2018-10-01 Stefan de Boer , Gudrun Hiller

In the present study, we investigate the decays of the top quark $t\rightarrow c\gamma$, $t\rightarrow cg$, $t\rightarrow cZ$ and $t\rightarrow ch$. They are extremely rare processes in the Standard Model (SM). As the $U(1)$ extension of…

High Energy Physics - Phenomenology · Physics 2024-07-30 Ming-Yue Liu , Shu-Min Zhao , Song Gao , Xing-Yu Han , Tai-Fu Feng

In this paper, we calculate the top quark rare decay t-ch in a supersymmetric extension of the standard model where baryon and lepton numbers are local gauge symmetries. Adopting reasonable assumptions on the parameter space, we find that…

High Energy Physics - Phenomenology · Physics 2014-10-07 Tie-Jun Gao , Tai-Fu Feng , Fei Sun , Hai-Bin Zhang , Shu-Min Zhao

We study the decay $t\rightarrow c\gamma$ with flavor-changing neutral interactions in scalar sector of the type III Two Higgs Doublet Model (THDM-III) with mixing between neutral scalar fields as a result of considering the most general…

High Energy Physics - Phenomenology · Physics 2014-07-30 R. Gaitan-Lozano , R. Martinez , J. H. Montes de Oca

We evaluate all two-body decay modes of the heavy scalar top quark in the Minimal Supersymmetric Standard Model with complex parameters (cMSSM) and no generation mixing. The evaluation is based on a full one-loop calculation of all decay…

High Energy Physics - Phenomenology · Physics 2013-05-30 T. Fritzsche , S. Heinemeyer , H. Rzehak , C. Schappacher

The experimental decay branching ratios of mesons like $B_s\to \ell\bar \ell$ and $B_d\to \ell\bar \ell$ ($\ell=e$ or $\mu$) do not agree completely with the standard model (SM). Cartan's supersymmetry predicts relation of the coupling of…

General Physics · Physics 2015-11-25 Sadataka Furui

QCD corrections to $b \to s \gamma$ decay in the two Higgs doublet model are calculated from the energy scale of top quark to that of bottom. The constraints on the two Higgs doublet model from the new experimental bounds of $b\to s\gamma$…

High Energy Physics - Phenomenology · Physics 2007-05-23 Cai-Dian Lu

If new physics (e.g. SUSY) does not show up as direct evidence at the LHC, it could still be observable in FCNC processes involving the $t$-quark. We take a close look at the process $t\to c + h/Z$ and show that its branching ratio in the…

High Energy Physics - Phenomenology · Physics 2017-05-25 Debjyoti Bardhan

We study the decay B\to X_s\gamma in a minimal extension of the standard model with extra up- and down-type quarks whose left- and right-handed components are both SU(2) singlets. Constraints on the extended Cabibbo-Kobayashi-Maskawa matrix…

High Energy Physics - Phenomenology · Physics 2009-10-31 Mayumi Aoki , Eri Asakawa , Makiko Nagashima , Noriyuki Oshimo , Akio Sugamoto

The various decay modes of the type $B \to \gamma D^* $ are dynamically different. In general there are factorizable contributions, and there are pole diagrams and pseudoscalar exchange contributions at meson level. The purpose of this…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. O. Eeg J. A. Macdonald Sørensen

Within the framework of the Top-color-assisted Technicolor (TC2) model, we calculate the new physics contributions to the branching ratios $\calb(B_{s,d} \to \gamma \gamma)$ and CP violating asymmetries $\rcpm(B_{s,d} \to \gamma \gamma)$ in…

High Energy Physics - Phenomenology · Physics 2016-08-16 Zhenjun Xiao , Cai-Dian Lü , Wujun Huo

The top quark decay process $\tcups$ is studied in the Standard Model and the Minimal Supersymmetric Standard Model with conserved and violated $R-$parity. In dealing with the heavy quarkonium, $\ups$, production, we take both color-singlet…

High Energy Physics - Phenomenology · Physics 2008-11-26 L. T. Handoko , C. -F. Qiao

The two Higgs doublet model for the top (T2HDM) is a 2HDM in which the top quark receives a special status, which endows it with a naturally large mass, and also gives rise to unique FC charged and neutral scalar interactions. We calculate…

High Energy Physics - Phenomenology · Physics 2007-11-09 Itzhak Baum

We investigate the radiative process of the $\Lambda_b\rightarrow \Lambda \gamma$ in the standard model as well as models with one or two compact universal extra dimensions. Using the form factors entered to the low energy matrix elements,…

High Energy Physics - Phenomenology · Physics 2013-07-22 K. Azizi , S. Kartal , A. T. Olgun , Z. Tavukoglu

The large value of the top quark mass implies that the rare top decays $t \rightarrow b W^+ Z, s W^+ Z$ and $d W^+ Z$, and $t \rightarrow c W^+ W^-$ and $u W^+ W^-$, are kinematically allowed decays so long as $m_t \ge m_W + m_Z + m_{d_i}…

High Energy Physics - Phenomenology · Physics 2008-11-26 Elizabeth Jenkins

We study the decays of top squarks (~t_{1,2}) and bottom squarks (~b_{1,2}) in the Minimal Supersymmetric Standard Model (MSSM) with complex parameters A_t, A_b, mu and M_1. We show that including the corresponding phases strongly affects…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Bartl , S. Hesselbach , K. Hidaka , T. Kernreiter , W. Porod

We discuss possible non-standard contributions to the top-quark width, particularly the virtual effects on the standard decay $t\rightarrow W^+\,b$ within the context of the MSSM. We also place a renewed emphasis on the unconventional mode…

High Energy Physics - Phenomenology · Physics 2008-02-03 Joan Sola

We study the decay mode of top quark decaying into Wb in the TC2 model where the top quark is distinguished from other fermions by participating in a strong interaction. We find that the TC2 correction to the decay width $\Gamma (t \to b W)…

High Energy Physics - Phenomenology · Physics 2011-03-23 Xuelei Wang , Qiaoli Zhang , Qingpeng Qiao