Köln 2004 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HK: Physik der Hadronen und Kerne
HK 5: Theory I
HK 5.5: Vortrag
Montag, 8. März 2004, 17:00–17:15, D
Chiral Perturbation Theory for Heavy Nuclei — •Akaki Rusetsky1, Luca Girlanda2, and Wolfram Weise2,3 — 1HISKP (Th), Universität Bonn, Bonn, Germany — 2ECT*, Trento, Italy — 3Physik-Department, TU München, Garching, Germany
We propose a novel formulation of Chiral Perturbation Theory in a nuclear background, characterized by a static, non-uniform distribution of the baryon number that describes the finite nucleus[1]. The proposed approach is directly applicable to study of the deeply bound (1s) states of pionic atoms formed with Pb and Sn isotopes, whose spectrum has been measured at GSI[2]. The results of this high-precision experiment have recently triggered a discussion about the possibility of observation of the “fingerprints of chiral restoration” in nuclear medium. This issue, however, can only be resolved, provided a systematic theoretical framework is available for the description of pionic atoms within Chiral Perturbation Theory, taking into account the effects of the finite nuclear size. The proposed approach intends to fill this gap. In addition, it opens perspectives for many applications of ChPT in nuclear physics – especially for the problems in which the finite boundaries of the system are crucial.
In the limiting case of a uniform distribution, the proposed framework[1] reduces to the well-known zero-temperature in-medium ChPT. We further use the approach to calculate the self-energy of the charged pion in the background of the heavy nucleus at O(p5) in the chiral expansion, and to derive the leading terms of the pion-nucleus optical potential.
[1] L. Girlanda, A. Rusetsky and W. Weise, arXiv:hep-ph/0311128.
[2] K. Suzuki et al., arXiv:nucl-ex/0211023.