Study of electron bremsstrahlung in strong coulomb fields at the ESR storage ring

T. Ludziejewski^a,b), Th. Stöhlker^a,c), S. Keller^d), H. Beyer^a), F. Bosch^a),
O. Brinzanescu^a), C. Kozhuharov^a), A. Krämer^a), D. Liesen^a),
P. H. Mokler^a), R. H. Pratt^e), P. Rymuza^b), C. D. Shaffer^f),
Z. Stachura^g), P. wiat^h), A. Warczak<sup>h)

a)</sup> Gesellschaft für Schwerionenforschung, D-64220 Darmstadt, Germany
^b)Institute for Nuclear Studies, 05-400 wierk, Poland
^c) University of Frankfurt, D-60486 Frankfurt, Germany
^d) University of Frankfurt, D-60054 Frankfurt, Germany
^e)University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
^f)Wayne State College, Wayne, NE 68787, USA
^g)Institute of Nuclear Physics, 31-342 Cracow, Poland
^h)Jagiellonian University, 30-059 Cracow, Poland

Abstract:

Electron bremsstrahlung has been investigated for collisions of 223.2 MeV/amu He-like uranium ions with N₂ and Ar gaseous targets. The doubly differential cross-sections for bremsstrahlung are compared to the predictions of relativistic first order Born calculations (Bethe-Heitler formula with Elwert correction factor) and to the calculations based on the exact wave-functions for electrons moving in the external point-Coulomb potential of the projectile. Whereas the ``exact'' IPA calculations give an improved agreement with experimental data, as compared to the Bethe-Heitler theory, in particular at the end-point region of the bremsstrahlung spectra, discrepancies still remain at lower photon energies.