Sprecher
Beschreibung
We developed a formalism to study momentum anisotropy, in particular, the collective flow $v_2$, in the ultra-relativistic onium-onium scattering. We derived the impact-parameter dependent cross section up to the next-to-leading order in the eikonal approximation. With this formalism, we are able to interpret the origin and behavior of $v_2$ in the dilute limit, by investigating the elementary dipole-dipole scattering, $q\bar q+q\bar q\to g+X$. We calculated $v_2$ in the $\pi+\pi\to g+X$ process at a comprehensive coverage of impact parameter and transverse momentum. The valence sector light-front wave function of the $\pi$ is obtained numerically from the Basis Light-Front Quantization, a non-perturbative light-front Hamiltonian approach, in a holographic basis. For comparison and as a complementary study, we also calculated $v_2$ in the $J/\psi+J/\psi\to g+X$ process. The $J/\psi$ light-front wavefunction is built analytically from the phenomenological framework of Small-basis Light-Front Wavefunction. With this work, we have shown that momentum anisotropy can develop due to the interference of the valence quarks. This formalism is generic and can be applied to other hadrons and photons in the future.
Affiliation
Universtiy of Santiago de Compostela, Shandong University
| Experiment/Theory | Theory/Phenomenology |
|---|