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Title: QCD and Standard Model Studies

Abstract

Our group has focused on using jets in STAR to investigate the longitudinal and transverse spin structure of the proton. We performed measurements of the longitudinal double-spin asymmetry for inclusive jet production that provide the strongest evidence to date that the gluons in the proton with x>0.05 are polarized. We also made the first observation of the Collins effect in pp collisions, thereby providing an important test of the universality of the Collins fragmentation function and opening a new tool to probe quark transversity in the proton. Our studies of forward rapidity electromagnetic jet-like events raise serious question whether the large transverse spin asymmetries that have been seen for forward inclusive hadron production arise from conventional 2 → 2 parton scattering. This is the final technical report for DOE Grant DE-FG02-93ER40765. It covers activities during the period January 1, 2015 through November 30, 2016.

Authors:
 [1]
  1. Texas A & M Univ., College Station, TX (United States)
Publication Date:
Research Org.:
Texas A & M Univ., College Station, TX (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Nuclear Physics (NP) (SC-26)
OSTI Identifier:
1345044
Report Number(s):
DOE-TAMU-40765
DOE Contract Number:
FG02-93ER40765
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Proton spin; gluon polarization; Collins effect; transverse single-spin asymmetries

Citation Formats

Gagliardi, Carl A. QCD and Standard Model Studies. United States: N. p., 2017. Web. doi:10.2172/1345044.
Gagliardi, Carl A. QCD and Standard Model Studies. United States. doi:10.2172/1345044.
Gagliardi, Carl A. Tue . "QCD and Standard Model Studies". United States. doi:10.2172/1345044. https://www.osti.gov/servlets/purl/1345044.
@article{osti_1345044,
title = {QCD and Standard Model Studies},
author = {Gagliardi, Carl A},
abstractNote = {Our group has focused on using jets in STAR to investigate the longitudinal and transverse spin structure of the proton. We performed measurements of the longitudinal double-spin asymmetry for inclusive jet production that provide the strongest evidence to date that the gluons in the proton with x>0.05 are polarized. We also made the first observation of the Collins effect in pp collisions, thereby providing an important test of the universality of the Collins fragmentation function and opening a new tool to probe quark transversity in the proton. Our studies of forward rapidity electromagnetic jet-like events raise serious question whether the large transverse spin asymmetries that have been seen for forward inclusive hadron production arise from conventional 2 → 2 parton scattering. This is the final technical report for DOE Grant DE-FG02-93ER40765. It covers activities during the period January 1, 2015 through November 30, 2016.},
doi = {10.2172/1345044},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Feb 28 00:00:00 EST 2017},
month = {Tue Feb 28 00:00:00 EST 2017}
}

Technical Report:

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