Effective Field Theory Approach to Pionium
نویسنده
چکیده
The various dynamical scales below the pion mass involved in π+ π− atoms are sequentially integrated out using non-relativistic effective field theory techniques. This allows us to systematically organise the corrections to the energy levels and decay width. We present our results in terms of a single unknown constant which may be obtained by matching to the Chiral Lagrangian with electromagnetic interactions at two loops.
منابع مشابه
ar X iv : h ep - p h / 99 05 54 3 v 1 2 9 M ay 1 99 9 Effective Field Theory Approach to Pionium
The various dynamical scales below the pion mass involved in π + π − atoms are sequentially integrated out using non-relativistic effective field theory techniques. This allows us to systematically organise the corrections to the energy levels and decay width. We present our results in terms of a single unknown constant which may be obtained by matching to the Chiral Lagrangian with electromagn...
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تاریخ انتشار 1999