Measurement of the Proton's Weak Charge at the Qweak Experiment
The Qweak experiment at Jefferson Laboratory measures the parity violating asymmetry of polarized electrons scattering from a proton target at very low momentum transfer. In the Standard Model, this asymmetry reveals the proton's coupling to the neutral vector current, the weak charge. This value, measured directly for the first time, will provide a precision test of the Standard Model and will constrain the possibility of relevant physics beyond the Standard Model. The planned precision will probe certain classes of new physics at the ~2 TeV scale. In order to challenge the precise predictions, the asymmetry will be measured with a 2.5 percent accuracy. To achieve such a precision, great care has to be taken on many aspects of the experiment. The very low momentum transfer reduces the hadronic effects to the asymmetry and must be determined to half of a percent accuracy. Beam stability is controlled and monitored constantly and background events are carefully studied.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- AC05-06OR23177
- OSTI ID:
- 1068964
- Report Number(s):
- JLAB-PHY-11-1447; DOE/OR/23177-1892; arXiv:1110.2218
- Resource Relation:
- Conference: Meeting of the Division of Particles and Fields of the American Physical Society (DPF11), August 9-13, 2011, Providence, Rhode Island; Related Information: JLAB-E08-016 (Qweak)
- Country of Publication:
- United States
- Language:
- English
Similar Records
Qweak: First Direct Measurement of the Weak Charge of the Proton
Searches for Physics beyond the Standard Model