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Title: Twist-3 fragmentation effects for A LT in light hadron production from proton-proton collisions

Here, we compute the contribution from the twist-3 fragmentation function for light hadron production in collisions between transversely and longitudinally polarized protons, i.e., View the MathML sourcep↑p →hX, which can cause a double-spin asymmetry (DSA) A LT. This is a naïve T-even twist-3 observable that we analyze in collinear factorization using both Feynman gauge and lightcone gauge as well as give a general proof of color gauge invariance. So far only twist-3 effects in the transversely polarized proton have been studied for A LT in p↑p →hX. However, there are indications that the naïve T-odd transverse single-spin asymmetry (SSA) A N in p↑p→hX is dominated not by such distribution effects but rather by a fragmentation mechanism. Therefore, one may expect similarly that the fragmentation contribution is important for A LT. As a result, given possible plans at RHIC to measure this observable, it is timely to provide a calculation of this term.
 [1] ;  [2] ;  [1] ;  [1]
  1. Niigata Univ., Niigata (Japan)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 0370-2693; R&D Project: PO-3
Grant/Contract Number:
Published Article
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 752; Journal Issue: C; Journal ID: ISSN 0370-2693
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Country of Publication:
United States
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Riken BNL Research Center; twist-3 effects; spin asymmetries; fragmentation
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1246797