Related papers: Finite one-loop radiative corrections in the Loren…
We calculate the one-photon loop radiative corrections to charged pion Compton scattering, $\pi^- \gamma \to \pi^- \gamma $. Ultraviolet and infrared divergencies are both treated in dimensional regularization. Analytical expressions for…
I review the main results leading to Factorization of QCD amplitudes in momentum space and, in view of the analogue results in coordinate space, the one-loop jet function in coordinate space is computed and Landau's equations for the…
We calculate the electroweak and QCD corrections to W-W+ -> tt and ZZ -> tt. We also consider the interplay of these corrections with the effect of anomalous interactions that affect the massive weak bosons and the top. The results at the…
QCD one-loop corrections to the semileptonic process $e^+ e^- \to \mu^- \bar \nu_\mu u \bar d$ are computed. We compare the exact calculation with a ``naive'' approach to strong radiative corrections which has been widely used in the…
We purpose a study a Lorentz-breaking extension of the scalar QED. We calculate the contributions in the Lorentz-violating parameters to the two-point functions of scalar and gauge fields. We found that the two background tensors, coming…
We use on-shell recursion relations to determine the one-loop QCD scattering amplitudes with a massless external quark pair and an arbitrary number (n-2) of positive-helicity gluons. These amplitudes are the last of the unknown infrared-…
We present the first next-to-leading-logarithmic QCD analysis of the electromagnetic corrections to the semileptonic weak Hamiltonian, including the mixed $\mathcal{O}(\alpha\,\alpha_s^2)$ corrections to the vector coupling $g_V$. The…
We present two novel results about the universal structure of radiative QED amplitudes in the soft and in the collinear limit. On the one hand, we extend the well-known Low-Burnett-Kroll theorem to the one-loop level and give the explicit…
Lorentz invariance is a cornerstone of modern physics, yet its possible violation remains both theoretically intriguing and experimentally significant. In this work, using quantum electrodynamics as an example, we explore how Lorentz…
We compute the complete one-loop corrections to the simplest class of QCD gluon amplitudes, those with two color-adjacent opposite-helicity external particles. We present results for an arbitrary number of external legs. The computation…
Radiative effects in the electroproduction of photons in polarized $ep$-scattering are calculated with the next-to-leading (NLO) accuracy. The contributions of loops and two photon emission were presented in analytical form. The covariant…
This talk at the CPT'19 meeting outlines a few recent developments in Lorentz and CPT violation, with particular attention to results obtained by researchers at the Indiana University Center for Spacetime Symmetries.
We explore the radiative corrections to the process $Z \to b \bar b$ in models with extended Higgs sectors. The observables $R_b = \Gamma(Z \to b \bar b)/\Gamma(Z \to \rm{hadrons})$ and the $Z b \bar b$ coupling asymmetry, $A_b = (g_L^2 -…
We perform detailed calculations of electroweak radiative corrections to parity violating lepton scattering with a proton target up to quadratic and reducible two-loop level using a covariant approach. Our numerical results are presented at…
The QED radiative corrections to virtual Compton scattering (reaction $e p \to e p \gamma$) are calculated to first order in $\alpha_{em} \equiv e^2 / 4 \pi$. A detailed study is presented for the one-loop virtual corrections and for the…
We compute the full vacuum polarization tensor in the minimal QED extension. We find that its low-energy limit is dominated by the radiatively induced Chern-Simons-like term and the high-energy limit is dominated by the c-type coefficients.…
Analytical calculation is presented of the QCD radiative corrections to the rate of the process $b\to c\tau\bar\nu_\tau$ and to the $\tau$ lepton longitudinal polarization in $\tau\bar\nu_\tau$ rest frame. The results are given in the form…
We calculate by the method of dimensional regularization and derivative expansion the one-loop effective action for a Dirac fermion with a Lorentz-violating and CPT-odd kinetic term in the background of a gauge field. We show that this term…
Using the infinite-volume photon propagator, we developed a method which allows us to calculate electromagnetic corrections to stable hadron masses with only exponentially suppressed finite-volume effects. The key idea is that the infinite…
QCD one-loop corrections to the full gauge invariant set of electroweak diagrams describing the hadronic process $e^+ e^- \to u~\bar d~s~\bar c$ are computed. Four-jet shape variables for $WW$ events are studied at next-to-leading order and…