Measurement of the anti-quark flavor asymmetry in the nucleon sea
- Univ. of Texas, Austin, TX (United States)
A precise measurement of the ratio of Drell-Yan yields from an 800 GeV/c proton beam incident on liquid hydrogen and deuterium targets is reported. Over 370,000 Drell-Yan muon pairs were recorded. From these data, the ratio of anti- down ($$\bar{d}$$) to anti-up ($$\bar{u}$$) quark distributions in the proton sea is determined over a wide range in Bjorken-x. A strong x dependence is observed in the ratio $$\bar{d}$$ / $$\bar{d}$$. From this result, the integral of ($$\bar{d}$$- $$\bar{u}$$) is evaluated for 0.015 < x < 0.35 and compared with deep inelastic scattering results. The origin of this asymmetry is probably due to non-perturbative effects such as those contained in pion cloud models. This measurement has instigated new global fits since previous parameterizations of the proton could not accommodate this large asymmetry.
- Research Organization:
- Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
- DOE Contract Number:
- AC02-07CH11359
- OSTI ID:
- 1155653
- Report Number(s):
- FERMILAB-THESIS--1999-26; UMI--99-47415
- Country of Publication:
- United States
- Language:
- English
Similar Records
Measurement of the Antiquark Flavor Asymmetry in the Nucleon Sea
Measurement of the light antiquark flavor asymmetry in the nucleon sea
Improved measurement of the {ovr d}/{ovr u} asymmetry in the nucleon sea.
Thesis/Dissertation
·
Tue May 01 00:00:00 EDT 2001
·
OSTI ID:1421416
Measurement of the light antiquark flavor asymmetry in the nucleon sea
Thesis/Dissertation
·
Sat Aug 01 00:00:00 EDT 1998
·
OSTI ID:3120
Improved measurement of the {ovr d}/{ovr u} asymmetry in the nucleon sea.
Journal Article
·
Sat Sep 01 00:00:00 EDT 2001
· Phys. Rev. D
·
OSTI ID:943279