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<div><font color="#000080"><b>Old Dominion University</b></font></div>
<div><font color="#000080"><b>Department of Physics</b></font></div>
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<div><font color="#31849B"><b>Spring Colloquium Series</b></font></div>
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<div><font color="#17365D" size="5"><b>Tuesday February 21, 2012</b></font></div>
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<div><font color="#31849B" size="5"><b>"Studies of the Building Blocks of Atomic Nuclei and the Onset of the Quark Parton Model"</b></font></div>
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<font color="#1F497D" size="5" face="Times New Roman, serif"><b>Dr. Rolf Ent</b></font></font></div>
<div><font color="#1F497D" size="5"><b>Jefferson Lab</b></font></div>
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<div><font size="3">The quarks and gluons of QCD are hidden. At high energies the property of QCD known as asymptotic freedom, which causes quarks to interact very weakly at short distances, allows for an efficient perturbative
description of the interior landscape of nucleons in terms of a sea of quarks and gluons with a few ever-present valence quarks. In contrast, protons and neutrons that are the constituents of nuclei are identified with color singlet states that have strong
interactions very different from that of the gluon exchange by colored quarks and gluons. Protons and neutrons rather seem bound together by the exchange of evanescent mesons at distance scales comparable to their sizes (~1 fm). Despite this apparent dichotomy,
a striking similarity between data measured at high and low energies is observed. As a corollary, the quark parton model, developed to describe high-energy scattering data, has been found to be remarkably successful in also describing data at relatively modest
energies of order 5 GeV. With the 12-GeV Jefferson Lab Upgrade, this will then in turn allow for a rich field of investigations of the underlying quark-gluon description of the building blocks of atomic nuclei.</font></div>
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<div><font size="4">Presentation: Physical Sciences Building II 1100 @ 3:00 pm</font></div>
<div><font size="4">Refreshments: 1st Floor Atrium @ 2:30 pm</font></div>
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<div><font size="4">More details at <a href="http://www.physics.odu.edu">
http://www.physics.odu.edu</a></font></div>
<div><font size="4">All are Welcome<font size="3">!</font></font></div>
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