Helicity-dependent showers and matching with VINCIA

• Main Authors: Larkoski, Andrew (Contributor), Lopez-Villarejo, J. J. (Author), Skands, P. (Author)
• Other Authors: Massachusetts Institute of Technology. Center for Theoretical Physics (Contributor)
• Format: Article
• Language: English
• Published: American Physical Society, 2013-07-12T19:00:38Z.
• Subjects: Article
• Online Access: Get fulltext

We present an antenna shower formalism that includes helicity dependence for massless partons. The formalism applies to both traditional (global) showers and sector-based variants. We combine the shower with vincia's multiplicative approach to matrix-element matching, generalized to operate on each helicity configuration separately. The result is a substantial gain in computational speed for high parton multiplicities. We present an implementation of both sector and global showers, with min/max variations, and helicity-dependent tree-level matching applied through n≤4 for V/H→qq̅ +n partons and through n≤5 for H→n gluons.
United States. Dept. of Energy (Contract DE-FG02-05ER41360)
National Science Foundation (U.S.) (Grant NSF-PHY-0969510)
U.S. LHC Theory Initiative