First observation of the parity violaing asymmetry in moller scattering

Thesis/Dissertation · Sat Nov 01 04:00:00 EST 2003

DOI:https://doi.org/10.2172/915445· OSTI ID:915445

Younus, Imran ^[1]

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1. Syracuse Univ., NY (United States)

This thesis reports on the E158 experiment at Stanford Linear Accelerator Center (SLAC), which has made the first observation of the parity non-conserving asymmetry in Moller scattering. Longitudinally polarized 48 GeV electrons are scattered off unpolarized (atomic) electrons in a liquid hydrogen target with an average Q² of 0.027 GeV². The asymmetry in this process is proportional to ( 1 4 ₋ sin2 θ_W), where sin² =W gives the weak mixing angle. The thesis describes the experiment in detail, with a particular focus on the design and construction of the electromagnetic calorimeter. This calorimeter was the primary detector in the experiment used to measure the flux of the scattered Moller electrons and eP electrons. It employed the quartz fiber calorimetry technique, and was built at Syracuse University. The preliminary results from the first experimental data taken in spring 2002 give APV = ₋151.9±29.0(stat)±32.5(syst) parts per billion. This in turn gives sin²θ_W = 0.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Energy Research (ER)
• DOE Contract Number: AC05-84ER40150
• OSTI ID: 915445
• Report Number(s): JLAB-PHY--03-239; DOE/ER/40150--4350
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
43 PARTICLE ACCELERATORS
ASYMMETRY
CALORIMETERS
CALORIMETRY
CONSTRUCTION
DESIGN
ELECTRONS
FIBERS
HYDROGEN
PARITY
QUARTZ
SCATTERING
STANFORD LINEAR ACCELERATOR CENTER
TARGETS