9th International Conference on High Energy Particle and Nuclear Physics in the LHC Era

Homotopy approach for scattering amplitude for running QCD coupling

7 Jan 2025, 17:30

20m

Building A (Santa Maria University)

parallel Parallel session 4: QCD (1/2)

Speaker

José Garrido (Universidad Técnica Federico Santa María)

Description

In this talk, I will present the development of the homotopy method for solving the nonlinear Balitsky-Kovchegov (BK) equation with a running QCD coupling. I will show how an analytic solution is obtained for a simplified equation with a leading-twist BFKL kernel, satisfying initial and boundary conditions. In the second stage, we calculate the corrections to this solution. These corrections were computed numerically, but the equation remains analytic, avoiding uncertainties. The first iteration achieves 5% accuracy, while the second iteration improves the accuracy to ≤ 1%. At high energies, the solution approaches the unitarity limit, reproducing key features such as "$\zeta$-scaling" and its breakdown at low $l-l_s$​.

Presentation materials

HEPNP2025_JoseGarrido.pdf