- th / 0 20 20 38 v 2 8 J ul 2 00 2 Chiral restoration from pionic atoms ?
نویسنده
چکیده
We evaluate widths and shifts of pionic atoms using a theoretical microscopical potential in which the pion decay constant fπ is changed by an in–medium density dependent one ( fπ(ρ)), predicted by different partial Chiral restoration calculations. We show that the results obtained for shifts and widths are worse than if this modification were not implemented. On the other hand, we argue that in microscopic many body approaches for the pion selfenergy, based on effective Lagrangians, the mechanisms responsible for the change of fπ in the medium should be automatically incorporated. Therefore, the replacement of fπ by fπ(ρ) in the many body derivation of the microscopic potential would be inappropriate.
منابع مشابه
- th / 0 20 20 38 v 1 1 2 Fe b 20 02 Chiral restoration from pionic atoms ?
We evaluate widths and shifts of pionic atoms using a theoretical microscopical potential in which the pion decay constant fπ is changed by the medium fπ(ρ) one, predicted by many different approaches. We show that the results obtained for shifts and widths are worse than if the correction is not implemented. Only in the case where one implements the modification in the real part of the s−wave ...
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