Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

QWEAK: a precision measurement of the proton's weak charge

Conference ·
OSTI ID:882272
The Q_weak experiment at Jefferson Lab will measure the parity-violating asymmetry in e-p elastic scattering at low Q^2 using a polarized electron beam and a LH_2 target. The experiment will provide the first measurement of the weak charge of the proton to an accuracy of 4%. Q^P_W is related to the weak mixing angle, and thus provides the means for a precision test of the SM. Since the value of sin^2 theta_w is approximately 1/4, the weak charge of the proton Q^p_w = 1 - 4sin^2 theta_w is suppressed in the SM, making it sensitive to the value of the mixing angle and to possible new physics. At the kinematics selected, the systematic uncertainties from hadronic processes are strongly suppressed.
Research Organization:
Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA
Sponsoring Organization:
USDOE - Office of Energy Research (ER)
DOE Contract Number:
AC05-84ER40150
OSTI ID:
882272
Report Number(s):
JLAB-PHY-04-60; DOE/ER/40150-3871
Country of Publication:
United States
Language:
English