English
Related papers

Related papers: CP Violation in radiative Z Decays

200 papers

The weak dipole moments of leptons and quarks, \ie those related to their $Z$--coupling, are reviewed. Standard Model predictions and experimental results may result in a stringent test for both their pointlike structure and also for the…

High Energy Physics - Phenomenology · Physics 2016-08-15 J. Bernabéu , G. A. González-Sprinberg , J. Vidal

We present a detailed estimate of the transverse muon polarization (P_T) due to electromagnetic final-state interactions in the decay $K^+ \to \mu^+ \nu \gamma$. This CP-conserving effect represents the dominant contribution to P_T within…

High Energy Physics - Phenomenology · Physics 2009-10-31 Gudrun Hiller , Gino Isidori

We use spin correlations to constrain anomalous $\tau$-lepton couplings at the LHC including its anomalous magnetic moment, electric dipole moment and weak dipole moments. Single spin correlations are ideal to probe interference terms…

High Energy Physics - Phenomenology · Physics 2015-09-02 Alper Hayreter , German Valencia

We study CP violation in fermion pair decays of neutral boson particles with spin 0 or 1. We study a new asymmetry to measure CP violation in $\eta, K_L \rightarrow \mu^+\mu^-$ decays and discuss the possibility of measuring it…

High Energy Physics - Phenomenology · Physics 2010-11-01 Xiao-Gang He , J. P. Ma , B. McKellar

In the presence of an electric dipole coupling of t-tbar to a photon, and an analogous "weak" dipole coupling to the Z, CP violation in the process e+e- --> t tbar results in modified polarization of the top and anti-top. This polarization…

High Energy Physics - Phenomenology · Physics 2008-11-26 Saurabh D. Rindani

The electric dipole moment of atomic $^{199}$Hg induced by the nuclear Schiff moment and tensor-pseudotensor electron-nucleus interactions has been calculated. For this, we have developed and employed a novel method based on the…

Atomic Physics · Physics 2009-12-29 K. V. P. Latha , D. Angom , B. P. Das , D. Mukherjee

Searches for CP violating effects in atoms and molecules provide important constrains on competing extensions to the standard model of elementary particles. In particular, CP violation in an atom leads to the CP-odd (T,P-odd) polarizability…

High Energy Physics - Experiment · Physics 2014-11-17 Boris Ravaine , M. G. Kozlov , Andrei Derevianko

We discuss in detail signals for CP violation in the Higgs boson and tau-slepton sectors through the production processes $\mu^+\mu^- \to \tilde{\tau}_i^- \tilde{\tau}_j^+$, where $i,j=1,2$ label the two $\tau$ slepton mass eigenstates in…

High Energy Physics - Phenomenology · Physics 2014-11-17 S. Y. Choi , M. Drees , B. Gaissmaier , Jae Sik Lee

We show that certain CP-odd momentum correlations in the production and subsequent decay of tau pairs in $e^+e^-$ collisions get enhanced when the electron beam is longitudinally polarized. Analytic expressions for these correlations are…

High Energy Physics - Phenomenology · Physics 2010-11-01 B. Ananthanarayan , Saurabh D. Rindani

We review CP-violating effects in Z --> 3 jet and Z --> 4 jet decays, assuming the presence of CP-violating effective Z b bbar G and Z b bbar G G couplings. Longitudinal beam polarization is included in the studies. We propose a direct…

High Energy Physics - Phenomenology · Physics 2011-03-23 O. Nachtmann , C. Schwanenberger

We consider the most general gauge-invariant, chirality-conserving contact interactions in the process e +e- -> gamma Z, of the type proposed Abraham and Lampe, in order to explore the possibility of CP violation at future linear colliders…

High Energy Physics - Phenomenology · Physics 2010-11-05 B. Ananthanarayan , Saurabh D. Rindani

CP violation in top physics is reviewed. The Standard Model has negligible effects, consequently CP violation searches involving the top quark may constitute the best way to look for physics beyond the Standard Model. Non-standard sources…

High Energy Physics - Phenomenology · Physics 2009-09-25 David Atwood , Shaouly Bar-Shalom , Gad Eilam , Amarjit Soni

We study the general Higgs-weak boson coupling with CP-violation via the process e+e- -> f \bar f h. We categorize the signal channels by sub-processes Zh production and ZZ fusion and construct four CP asymmetries by exploiting polarized…

High Energy Physics - Phenomenology · Physics 2014-11-17 T. Han , J. Jiang

Aiming at a model-independent analysis of possible new physics effects in semileptonic processes at various energy scales, we list and study a complete set of $SU(3)_c\times SU(2)_L\times U(1)_Y$ invariant 4-Fermi operators which consist of…

High Energy Physics - Phenomenology · Physics 2007-05-23 We-Fu Chang , John N. Ng

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

The B -> K^* l^+ l^- (l = mu, tau) is analyzed in a minimally extended Standard Model in which the Wilson coefficients have new CP-odd phases. The sensitivity of the CP asymmetry and lepton polarization asymmetries to the new phases is…

High Energy Physics - Phenomenology · Physics 2011-03-23 T. M. Aliev , D. A. Demir , M. Savci

We study CP violation in the lepton sector of the supersymmetric extension of the Standard Model with three generations of massive singlet neutrinos with Yukawa couplings $Y_\nu$ to lepton doublets, in a minimal seesaw model for light…

High Energy Physics - Phenomenology · Physics 2008-11-26 John Ellis , Junji Hisano , Smaragda Lola , Martti Raidal

We study how to probe the anomalous CP-violating couplings of top quark with photon, Z and gluon in the ttbar threshold region at future e+e- colliders. These couplings contribute to the difference of the t and tbar polarization vectors…

High Energy Physics - Phenomenology · Physics 2014-11-17 M. Jezabek , T. Nagano , Y. Sumino

Rare kaon decays are an important testing ground of the electroweak flavor theory: They can provide new signals of CP-violating phenomena. The interplay of long-distance QCD effects in strangeness-changing transitions can be analyzed with…

High Energy Physics - Phenomenology · Physics 2007-05-23 Fabrizio Gabbiani

Observing charge-parity (CP) or time-reversal (T) violations in the leptonic sector will give useful information to elucidate the nature of neutrinos. CP-violating couplings in charged leptonic currents carry out the weak phases necessary…

High Energy Physics - Phenomenology · Physics 2010-03-11 G. López Castro , L. López-Lozano , A. Rosado