Taking dibaryon fields seriously
نویسندگان
چکیده
We propose a low energy effective field theory of QCD at the scale of pion mass for the NB = 2 sector, NB being the baryon number, which contains two dibaryon fields in addition to the nucleons and pions. It has a well defined counting, is renormalizable and the nucleon-nucleon scattering amplitudes are manifestly unitary at leading order. We work out a lower energy effective theory for nucleons with energy much lower than the pion mass and three momentum comparable to it, which also has a well defined counting and is renormalizable. The dibaryon fields must also be kept as explicit degrees of freedom in this theory. We calculate the scattering amplitudes at next-toleading order for the S0 and S1 channels in this framework and obtain an excellent description of the phase shifts for center of mass energies in the 0− 50MeV range. PACS: 14.20.Pt, 13.75.Cs, 21.30.Fe, 21.45.Bc, 03.65.Nk .
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