Building Blocks for Subleading Helicity Operators
Abstract
On-shell helicity methods provide powerful tools for determining scattering amplitudes, which have a one-to-one correspondence with leading power helicity operators in the Soft-Collinear Effective Theory (SCET) away from singular regions of phase space. We show that helicity based operators are also useful for enumerating power suppressed SCET operators, which encode subleading amplitude information about singular limits. In particular, we present a complete set of scalar helicity building blocks that are valid for constructing operators at any order in the SCET power expansion. We also describe an interesting angular momentum selection rule that restricts how these building blocks can be assembled.
Keywords
Cite
@article{arxiv.1601.02607,
title = {Building Blocks for Subleading Helicity Operators},
author = {Daniel W. Kolodrubetz and Ian Moult and Iain W. Stewart},
journal= {arXiv preprint arXiv:1601.02607},
year = {2016}
}
Comments
22 pages without references, 2 figures v2. Updated minor typo in Table 1