Year: 2018
Type: article
Abstract: A bstract We consider the expansion of small- x resummed DGLAP splitting functions at next-to-leading logarithmic (NLL) accuracy to four-loop order, namely next-to-next-to-next-to-leading order (N 3 LO). From this, we extract the exact LL and NLL small- x contributions to the yet unknown N 3 LO splitting functions, both in the standard $$ \overline{\mathrm{MS}} $$ M S ¯ scheme and in the Q 0 $$ \overline{\mathrm{MS}} $$ M S ¯ scheme usually considered in small- x literature. We show that the impact of unknown subleading logarithmic contributions (NNLL and beyond) at N 3 LO is significant, thus motivating future work towards their computation. Our results will be also needed in future to match NLL resummation to N 3 LO evolution. In turn, we propose an improved implementation of the small- x resummation and therefore release a new version of the resummation code (HELL 3.0) which contains these changes.
Source: Journal of High Energy Physics
Authors: Marco Bonvini, Simone Marzani
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W2804153144