Abstract
The paper describes the analytical calculation of helicity amplitudes for hard photon and gluon bremsstrahlung using the spinor formalism for processes such as \(\bar{q}q\to g\gamma\) and \(qg\to q\gamma\) . The presented amplitudes are expressed in terms of strength bivectors. The dependence on particle helicities and masses is taken into account. Numerical calculations have been performed for the annihilation process of a \(\bar{c}c\) quark pair at energies of 24, 91, and 500 GeV in the center-of-mass frame, taking into account various combinations of the helicities of the quarks and the photon in the final state. The study is part of the ongoing development of a theoretical framework within the SANC system, aimed at analyzing polarized observables in proton–proton collisions at the NICA collider.
