Beam Physics
Seminar
Sponsored by the Accelerator
Division
"Electron Beam Polarimetry at Jefferson Lab"
Dave Gaskell,
Jefferson Lab
Knowledge of the
polarization of the electron beam is the limiting systematic uncertainty
for an increasing number of experiments at Jefferson Lab. For example,
the Qweak experiment in Hall C and PREX experiment in Hall A both
require a systematic uncertainty of dP/P=1% (or better) for the beam
polarization. Future experiments proposed for 12 GeV are striving for
0.5%. In this presentation, I will give an overview of the techniques
and devices used at Jefferson Lab to measure the electron beam
polarization. In addition, I will discuss some of the efforts underway
to either upgrade these devices or build new devices with the goal of
improving the precision of polarization measurements. I will argue that
the prudent experimentalist cannot rely on any single device exclusively
and that multiple measurements of the polarization with multiple devices
(in the same experimental hall as well as cross-hall comparisons) are
key to achieving the high precision required.
Thursday, February 14, 2008
3:30 p.m.
ARC, Room 231/233
Talk Slides: (Slides)
For more information, please
contact Dr.
Alex Bogacz, Chair of CASA Seminar Committee
contact casaweb@jlab.org