Beam functions for N-jettiness at N$^3$LO in perturbative QCD

Autor: Daniel Baranowski, Arnd Behring, Kirill Melnikov, Lorenzo Tancredi, Christopher Wever
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Journal of High Energy Physics, 2023 (2), Art.-Nr.: 73
Journal of High Energy Physics
ISSN: 1029-8479
1126-6708
1127-2236
DOI: 10.5445/ir/1000156396
Popis: We present a calculation of all matching coefficients for $N$-jettiness beam functions at next-to-next-to-next-to-leading order (N$^3$LO) in perturbative quantum chromodynamics (QCD). Our computation is performed starting from the respective collinear splitting kernels, which we integrate using the axial gauge. We use reverse unitarity to map the relevant phase-space integrals to loop integrals, which allows us to employ multi-loop techniques including integration-by-parts identities and differential equations. We find a canonical basis and use an algorithm to establish non-trivial partial fraction relations among the resulting master integrals, which allows us to reduce their number substantially. By use of regularity conditions, we express all necessary boundary constants in terms of an independent set, which we compute by direct integration of the corresponding integrals in the soft limit. In this way, we provide an entirely independent calculation of the matching coefficients which were previously computed in arXiv:2006.03056.
Comment: 57 pages, 3 figures, 4 ancillary files
Databáze: OpenAIRE
Externí odkaz: