Low-energy photon–photon collisions to two loops revisited
نویسندگان
چکیده
منابع مشابه
The Low Energy π π Amplitude To One and Two Loops
The low-energy ππ amplitude is computed explicitly to two-loop accuracy in the chiral expansion. It depends only on six independent (combinations of) low-energy constants which are not fixed by chiral symmetry. Four of these constants are determined via sum rules which are evaluated using ππ scattering data at higher energies. Dependence of the low-energy phase shifts and of the threshold param...
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ژورنال
عنوان ژورنال: Nuclear Physics B
سال: 2005
ISSN: 0550-3213
DOI: 10.1016/j.nuclphysb.2005.09.010