Helicity evolution at smallx
We construct smallx evolution equations which can be used to calculate quark and antiquark helicity TMDs and PDFs, along with the g1 structure function. These evolution equations resum powers of α _{s} ln ^{2}(1/x) in the polarizationdependent evolution along with the powers of α _{s} ln(1/x) in the unpolarized evolution which includes saturation efects. The equations are written in an operator form in terms of polarizationdependent Wilson linelike operators. While the equations do not close in general, they become closed and selfcontained systems of nonlinear equations in the largeN _{c} and largeN _{c} & N _{f} limits. As a crosscheck, in the ladder approximation, our equations map onto the same ladder limit of the infrared evolution equations for g _{1} structure function derived previously by Bartels, Ermolaev and Ryskin.
 Authors:

^{[1]};
^{[2]};
^{[2]}
 The Ohio State Univ., Columbus, OH (United States)
 Brookhaven National Lab. (BNL), Upton, NY (United States)
 Publication Date:
 Report Number(s):
 BNL1116242015JA; BNL1122092016JA
Journal ID: ISSN 10298479; R&D Project: PO3
 Grant/Contract Number:
 SC00112704
 Type:
 Accepted Manuscript
 Journal Name:
 Journal of High Energy Physics (Online)
 Additional Journal Information:
 Journal Name: Journal of High Energy Physics (Online); Journal Volume: 2016; Journal Issue: 1; Journal ID: ISSN 10298479
 Publisher:
 Springer Berlin
 Research Org:
 Brookhaven National Laboratory (BNL), Upton, NY (United States)
 Sponsoring Org:
 USDOE Office of Science (SC), Nuclear Physics (NP) (SC26)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; resummation; perturbative QCD
 OSTI Identifier:
 1232702
 Alternate Identifier(s):
 OSTI ID: 1295201
Kovchegov, Yuri V., Pitonyak, Daniel, and Sievert, Matthew D.. Helicity evolution at smallx. United States: N. p.,
Web. doi:10.1007/JHEP01(2016)072.
Kovchegov, Yuri V., Pitonyak, Daniel, & Sievert, Matthew D.. Helicity evolution at smallx. United States. doi:10.1007/JHEP01(2016)072.
Kovchegov, Yuri V., Pitonyak, Daniel, and Sievert, Matthew D.. 2016.
"Helicity evolution at smallx". United States.
doi:10.1007/JHEP01(2016)072. https://www.osti.gov/servlets/purl/1232702.
@article{osti_1232702,
title = {Helicity evolution at smallx},
author = {Kovchegov, Yuri V. and Pitonyak, Daniel and Sievert, Matthew D.},
abstractNote = {We construct smallx evolution equations which can be used to calculate quark and antiquark helicity TMDs and PDFs, along with the g1 structure function. These evolution equations resum powers of αs ln2(1/x) in the polarizationdependent evolution along with the powers of αs ln(1/x) in the unpolarized evolution which includes saturation efects. The equations are written in an operator form in terms of polarizationdependent Wilson linelike operators. While the equations do not close in general, they become closed and selfcontained systems of nonlinear equations in the largeNc and largeNc & Nf limits. As a crosscheck, in the ladder approximation, our equations map onto the same ladder limit of the infrared evolution equations for g1 structure function derived previously by Bartels, Ermolaev and Ryskin.},
doi = {10.1007/JHEP01(2016)072},
journal = {Journal of High Energy Physics (Online)},
number = 1,
volume = 2016,
place = {United States},
year = {2016},
month = {1}
}