TMD factorization and evolution at large $$b_T$$

Conference · Mon Jul 20 00:00:00 EDT 2015

OSTI ID:1223378

Collins, John ^[1]; Rogers, Ted ^[2]

---

1. Pennsylvania State Univ., University Park, PA (United States)
2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Old Dominion Univ., Norfolk, VA (United States)

In using transverse-momentum-dependent (TMD) parton densities and fragmentation functions, important non-perturbative information is at large transverse position $$b_T$$. This concerns both the TMD functions and their evolution. Fits to high energy data tend to predict too rapid evolution when extrapolated to low energies where larger values of $$b_T$$ dominate. I summarize a new analysis of the issues. It results in a proposal for much weaker $$b_T$$ dependence at large $$b_T$$ for the evolution kernel, while preserving the accuracy of the existing fits. The results are particularly important for using transverse-spin-dependent functions like the Sivers function.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1223378
• Report Number(s): JLAB-THY-15-2024; DOE/OR/23177-3525; arXiv:1507.05542; TRN: US1601418
• Resource Relation: Conference: XXIII International Workshop on Deep-Inelastic Scattering and Related Subjects, Dallas, TX (United States), 27 Apr - 1 May 2015
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
DATA
ENERGY DEPENDENCE
FUNCTIONS
TRANSVERSE MOMENTUM
QUARKS
DENSITY
FACTORIZATION
ACCURACY
FRAGMENTATION
KERNELS