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<pre wrap="">Theory Center Seminar
Tuesday, Feb. 2, 2010
1:00 p.m.
CEBAF Center, Room L104
Coffee at 12:45 p.m.
<b>Subtractive Renormalization of Chiral Effective Theory NN Potentials Up
to Next-to-Next-to Leading Order</b>
Chieh Jen Yang
Ohio University
We have developed a subtractive renormalization method with which we can
evaluate NN scattering phase shifts produced by the NN potential
obtained at leading, next-to-leading, and next-to-next-to-leading order
(NNLO) in the chiral effective theory. In this method the low-energy
constants associated with short-distance NN physics are eliminated from
the Lippmann-Schwinger equation (LSE) for the NN t-matrix, in favor of
physical observables. This allows to straightforwardly compute
scattering phase shifts for ultra-violet cutoffs of at least 10 GeV. We
then perform detailed analyses of several renormalization issues and
determine the maximum cutoff at which the use of an effective field NN
potential in the LSE makes sense.</pre>
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