Related papers: Complete angular analysis of polarized top decay a…
We calculate one-loop R-parity violating corrections to the top quark decay into a bottom quark and a polarized W-gauge boson. The corrections are presented according to the total corrections, the longitudinal corrections and the transverse…
An optimal-observable analysis of the angular and energy distributions of the leptons and bottom quarks in the process e+e- --> tt-bar --> l^{+-}/b(b-bar)... has been performed in order to measure the most general top-quark couplings to…
We study the measurement of the quark fragmentation functions for spin-1/2 baryon production ($\Lambda$ and $\bar \Lambda$, in particular) in unpolarized $e^+e^-$ annihilation. The spin-dependent fragmentation functions $\hat g_1(z)$ and…
In the leading order of the (1/m_b)-expansion in HQET the dominant contribution to the semi-inclusive decays of polarized Lambda_b baryons into the charm-strangeness mesons D_s and D_s^* is given by the partonic process b(up) -> c + (D_s^-,…
Theoretical results are presented for top quarks produced in annihilation of polarized electrons on positrons. Polarization studies for $t\bar t$ pairs near threshold are free from hadronization ambiguities. This is due to the short…
We calculate the b-dependent self-energy of the top quark at O(g^2 \alpha_s) by using a general massive two-loop algorithm proposed in a previous article. From this we derive by unitarity the O(\alpha_s) radiative corrections to the decay…
We perform perturbative QCD factorization of infrared radiations associated with an energetic $b$ quark from a polarized top quark decay, taking the semi-leptonic channel as an example. The resultant formula is expressed as a convolution of…
Order $\beta_0^n \alpha_s^{n+1}$ QCD corrections to top quark decays into $W^+$ and $H^+$ bosons are computed to all orders in perturbation theory. Predictions for the radiative corrections to the top quark width are compared with the…
We provide analytical results for the $O(\alpha_s)$ corrections to the polar angle dependence of the longitudinal spin-spin correlation asymmetry in $e^+e^-\to q\bar q$. For top quark pair production the $O(\alpha_s)$ corrections to the…
In the presence of an electric dipole coupling of $t \bar t$ to a photon, and an analogous ``weak" dipole coupling to the $Z$, $CP$ violation in the process $e^+e^- \rightarrow t \bar t$ leads to the polarization of the top and anti-top.…
The polarization of the $W$ boson in $t \to W b$ decay is unambiguously predicted by the Standard Model of weak interactions and is a powerful test of our understanding of the $tbW$ vertex. The subsequent $W \to l \nu$ decay serves as a…
When a top quark is highly boosted, the $W$ boson from its decay has a substantial linear polarization that results in a $\cos 2\phi$ azimuthal angular correlation among the top decay products. We show that this correlation can be measured…
Analytic formulae are given for QCD corrections to the lepton spectra in decays of polarised up and down type heavy quarks. These formulae are much simpler than the published ones for the corrections to the spectra of charged leptons…
When a top quark decays there is a large amount of angular correlation, in its rest frame, between its spin orientation and the direction of flight of the charged lepton from its decay. In this letter we investigate the prospects of…
We compute the supersymmetric QCD corrections to the decay distribution of polarized top quarks for the semileptonic decay mode $t(\uparrow)\to b l^+\nu_l$. As a byproduct, we reinvestigate the SUSY-QCD corrections to the total decay width…
Full one-loop electroweak-corrections for an $e^-e^+\rightarrow t \bar{t}$ process associated with sequential $t\rightarrow b \mu\nu_\mu$ decay are discussed. At the one-loop level, the spin-polarization effects of the initial electron and…
Since the discovery of parity violation in 1957, angular distributions of leptons coming from the weak decay of polarized fermions have been used to probe the structure of the Wqq' vertex. Vector and axial vector couplings reveal themselves…
Angular distribution of the final particles in the decay $\Lambda_c^+\to K^- \, \Delta (1232)^{++} \to K^- \, p \, \pi^+$ of the polarized charmed baryon is discussed. Asymmetries are proposed which allow for determination of the components…
Analytic expression for energy and angular dependence of a secondary charged lepton in the decay of a polarized top quark with anomalous $tWb$ couplings in the presence of all anomalous couplings are derived. The angular distribution of the…
Corrections of $O(\alpha_s^2)$ to the decay of the top quark into a W boson and a bottom quark are calculated. The method is based on an expansion of the top quark propagator for small external momentum, q, as compared to the top quark…