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<font color="#000099"><b><font color="#3333ff">Physics Seminar<br>
Friday, December 4, 2009<br>
11:00AM<br>
CEBAF Center AUD.<br>
Cookies & Coffee at 10:45AM</font></b><br>
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<b><font color="#990000">"Measurements of Electric Form Factor of the
Neutron at High Momentum Transfer"
<br>
<br>
Seamus Riordan
<br>
University of Virginia
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<br>
The electric and magnetic form factors of the nucleons parameterize
elastic scattering in the one photon exchange approximation and provide
experimental access to the underlying quark charge and magnetic moment
distributions. These form factors are excellent testing grounds for
QCD and QCD-inspired models and are of fundamental importance in our
understanding of non-perturbative QCD. Of the four nucleon form
factors, the electric form factor of the neutron, GEn, has been
measured in the smallest range of momentum transfer. Hall A at
Jefferson Lab has recently performed measurements of GEn which greatly
extend the range in Q<sup class="moz-txt-sup">2</sup> and new
experiments have been approved for the 12 GeV upgrade to extend the
range even further. Results for GEn at three Q<sup class="moz-txt-sup">2</sup>
points, 1.7, 2.5 and 3.5 GeV<sup class="moz-txt-sup">2</sup> will be
presented and compared with QCD-based models and phenomenological
approaches. An overview of approved 12 GeV GEn measurements will also
be presented.
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Upcoming Seminar:
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<br>
Dec. 15 - Heidi Schellman (Northwestern)<br>
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