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We propose a method of measuring the CP-odd part of the Yukawa interaction of Higgs boson and $\tau$ leptons by observing the forward-backward asymmetry in the decay $H \to \tau^+ \, \tau^- \, \gamma$. The source of such asymmetry is the…

High Energy Physics - Phenomenology · Physics 2024-04-16 Erlend Aakvaag , Nikolai Fomin , Anna Lipniacka , Stefan Pokorski , Janusz Rosiek , Dibyakrupa Sahoo

We present a new measurement of the time-dependent CP-violating parameters in B0 --> pi+ pi- decays with 275 x 10^6 BB-bar pairs collected with the Belle detector at the KEKB asymmetric-energy e+e- collider operating at the Upsilon(4S)…

High Energy Physics - Experiment · Physics 2008-11-26 Belle Collaboration , K. Abe

The extraction of CKM-matrix-element information from hadronic B-decays generally suffers from discrete ambiguities, hampering the diagnosis of physics beyond the Standard Model. We show that a measurement of the rate asymmetry, which is…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Gardner , H. B. O'Connell , A. W. Thomas

In the framework of Perturbative QCD (PQCD) approach we study the direct $CP$ asymmetry for the decay channel $\bar{B}_{s}\rightarrow P\pi^+\pi^-$ around the resonance range via the $\rho-\omega$ mixing mechanism (where P refer to…

High Energy Physics - Phenomenology · Physics 2018-07-25 Gang Lü , Yu-Ting Wang , Qin-Qin Zhi

We study direct CP violation in the bottom baryon decays \Lambda_b -> f \rho^0 (\omega) -> f\pi^+\pi^- (f=n or \Lambda). It is found that in these decays via \rho-\omega mixing the CP violation could be very large when the invariant mass of…

High Energy Physics - Phenomenology · Physics 2010-02-17 X. -H. Guo , A. W. Thomas

Using a sample of $(225.2\pm 2.8)\times 10^6$ $J/\psi$ events collected with the Beijing Spectrometer (BESIII) at the Beijing Electron-Positron Collider, CP and $P$ violating decays of $\eta$, $\eta'$ and $\etac$ into $\pi^+\pi^-$ and…

High Energy Physics - Experiment · Physics 2011-09-08 The BESIII Collaboration , M. Ablikim

Strictly within the standard electro-weak interaction, CP violation in the flavour conserving process $\eta \ra \pi + \pi $ could originate from the mixing of the $\eta$ meson with the virtual scalar Higgs $ H^{0}$ via $ W^{+}+W^{-}$ and…

High Energy Physics - Phenomenology · Physics 2007-05-23 X. Y. Pham

We report improved measurements of B decays with an eta meson in the final state using 492 fb^{-1} of data collected by the Belle detector at the KEKB e^+ e^- collider. We observe the decays B^{+-}-> eta pi^{+-} and B^{+-}-> eta K^{+-}; the…

High Energy Physics - Experiment · Physics 2019-08-14 P. Chang

We study effects of CP violation in the associated production of a charged Higgs boson and a top quark at the LHC, $pp \to tH^\pm + X$. We calculate the CP violating asymmetry between the total cross section for $H^+$ and $H^-$ production…

High Energy Physics - Phenomenology · Physics 2009-10-29 E. Christova , H. Eberl , E. Ginina , W. Majerotto

Recently observed increase of direct CP asymmetry in charm meson nonleptonic decays is difficult to explain within the SM. If this effect is induced by new physics, this might be investigated in other charm processes. We propose to…

High Energy Physics - Phenomenology · Physics 2013-03-27 Svjetlana Fajfer , Nejc Kosnik

We present updated measurements of the CP-violating parameters S_pipi and C_pipi in B0 -> pi+pi- decays. Using a sample of 227 million Y(4S) -> BBbar decays collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at…

High Energy Physics - Experiment · Physics 2008-11-26 B. Aubert , BaBar Collaboration

We study in a model-independent way anomalous CP-violating tbW effective couplings that might arise from new physics in the processes pp-> tW^- X and pp-> tbar W^+X, followed by semileptonic decay of t and tbar. These processes have a…

High Energy Physics - Phenomenology · Physics 2012-05-22 Saurabh D. Rindani , Pankaj Sharma

In perturbative QCD approach, we study the direct $CP$ violation in the decay of $\bar{B}_s^0\to\rho(\omega )\phi\to {\pi^+}{\pi^-}\phi$ via isospin symmetry breaking. An interesting mechanism involving the charge symmetry violating between…

High Energy Physics - Phenomenology · Physics 2019-06-19 Sheng-Tao Li , Gang Lü

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 discovery of leptonic CP violation is one of the primary goals of next-generation neutrino oscillation experiments, which is feasible due to the recent measurement of a relatively large leptonic mixing angle \theta_{13}. We suggest two…

High Energy Physics - Phenomenology · Physics 2013-03-19 Tommy Ohlsson , He Zhang , Shun Zhou

We consider CP-violating effects in tau -> 3 pi nu_ tau and 4 pi nu_ tau (Delta S = 0), and tau -> K pi pi nu_tau (Delta S = 1), assuming that the usual Standard Model amplitudes for these processes interfere with analogous amplitudes…

High Energy Physics - Phenomenology · Physics 2013-01-01 Ken Kiers

We show that an anomalous CP-violating gamma-gamma-Z vertex gives rise to a novel asymmetry with transversely polarized electron and positron beams in the process e+e- -> gamma Z. This asymmetry, which is odd under naive time reversal, is…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Ananthanarayan , Saurabh D. Rindani , Ritesh K. Singh , A. Bartl

C-odd asymmetry can be studied from an accurate measurement of the angular distribution due to the interference between the S- and P-waves in e+e- --> pi+ pi- at order alpha^3. The asymmetry is dominated by the pion rescattering diagram…

High Energy Physics - Phenomenology · Physics 2009-09-29 J. Layssac , S. Narison

In this talk I discuss CP violation in hyperon decays in Left-Right symmetric models. I show that the asymmetry in polarization in $\Lambda \to p\pi^-$ can be as large as $6\times 10^{-4}$ in these models, which is an order of magnitude…

High Energy Physics - Phenomenology · Physics 2016-09-01 Xiao-Gang He

Using the experimental upper bound on the neutron EDM and experimental result on $b\rightarrow s\gamma$ branching ratio we have calculated CP asymmetry and $\Gamma^{2HDM}(b\rightarrow s{\it{l^{+}l^{-}}})/\Gamma^{SM}(b\rightarrow…

High Energy Physics - Phenomenology · Physics 2009-10-28 T. M. Aliev , D. A. Demir , E. Iltan , N. K. PAK