Fries, R. J. and Schaefer, A. and Weiss, C. (2003) Polarized antiquark flavor asymmetry Delta(u)over-bar(x)-Delta(d)over-bar(x) and the pion cloud. EUROPEAN PHYSICAL JOURNAL A, 17 (4). pp. 509-512. ISSN 1434-6001
Full text not available from this repository.Abstract
The flavor asymmetry of the unpolarized antiquark distributions in the proton, (v) over bar (x) - (d) over bar (x) < 0, can qualitatively be explained as an effect of the pion cloud. Corresponding predictions have been made for the polarized asymmetry, Delta(u) over bar (x) - Delta(d) over bar (x), based on rho-meson contributions. These estimates differ in sign and magnitude from those obtained in quark-based models, which give Delta(u) over bar (x) - Delta(d) over bar (x) > 0. Using a simple chiral linear sigma model as an example, we demonstrate that in the meson cloud picture a large positive Delta(u) over bar (x) - Delta(d) over bar (x) can be obtained from pi-sigma interference contributions. This calls into question previous estimates based on rho-meson contributions alone, and indicates how the results of the meson cloud picture may be reconciled with those of quark-based models.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | INELASTIC LEPTON SCATTERING; SEMIINCLUSIVE SPIN ASYMMETRIES; DRELL-YAN PROCESSES; LIGHT-QUARK SEA; MESON-CLOUD; PARTON DISTRIBUTIONS; NUCLEON SEA; FORM-FACTORS; PROTON; LIMIT; |
| Subjects: | 500 Science > 530 Physics |
| Divisions: | Physics > Institute of Theroretical Physics > Chair Professor Schäfer > Group Andreas Schäfer |
| Depositing User: | Dr. Gernot Deinzer |
| Date Deposited: | 10 Aug 2021 13:30 |
| Last Modified: | 10 Aug 2021 13:30 |
| URI: | https://pred.uni-regensburg.de/id/eprint/38852 |
Actions (login required)
 |
View Item |
