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<font color="#000099"><b><font color="#3333ff">Physics Seminar<br>
</font></b></font><font color="#3333ff"><b>April 13, 2012<br>
11:00 AM<br>
CEBAF Center AUD.<br>
Cookies and Coffee 10:45AM<br>
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<b><font color="#990000">Xiaochao Zheng
<br>
University of Virginia
<br>
<br>
"Measurement of the Parity Violation Asymmetry in Deep Inelastic
Scattering"</font>
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The parity violation asymmetry in electron deep inelastic scattering
off an isoscalar target such as the deuteron is sensitive to the
electroweak neutral couplings of electrons and quarks, as well as the
deuteron structure. During the JLab 6 GeV PVDIS experiment in 2009,
this asymmetry was measured at two Q2 values of 1.1 and 1.9 GeV$^2$, to
statistical precisions of 3\% and 4\%, respectively. Assuming the
higher twist effect to be small compared to the uncertainty of the
measurement, the asymmetry at 1.9 GeV<sup class="moz-txt-sup">2</sup>
is used to extract the EW coupling combination $2C_{2u}-C_{2d}$. The
asymmetries at both Q2 values were used to perform a simutaneous fit to
the $C_{2q}$ and the higher twist coefficient $\beta_{HT}$.
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<br>
In this talk I will review the experiment and describe all systematic
uncertainties. I will present the final results on the asymmetries.
Because the radiative corrections are not completely done, I will
present only the preliminary uncertainty on $2C_{2u}-C_{2d}$ and
$\beta_{HT}$.
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