https://doi.org/10.1140/epjc/s10052-007-0473-6
Regular Article - Theoretical Physics
Field-theoretical approach to particle oscillations in absorbing matter
Institute for Nuclear Research of RAS, 60th October Anniversary Prospect 7a, 117312, Moscow, Russia
* e-mail: nazaruk@inr.ru
Received:
1
July
2007
Published online:
6
December
2007
The ab oscillations in absorbing matter are considered. The standard model based on an optical potential does not describe the total ab transition probability as well as the channel corresponding to absorption of the b-particle. We calculate directly the off-diagonal matrix element in the framework of the field-theoretical approach. Contrary to the one-particle model, the final-state absorption does not tend to suppress the channels mentioned above; or, similarly, calculation with a Hermitian Hamiltonian leads to an increase of the corresponding values. Our approach reproduces all the results on the particle oscillations; however, it is oriented to the description of the above-mentioned channels. Also we touch on the general problems of the theory of reactions and decays; in particular, on infrared divergences. The approach in our study is infrared-free. For the correct construction and verification of the models of complicated processes, we propose the use of the low-density limit for the intermediate-state particle.
© Springer-Verlag , 2008