Radiative Electron Capture to Continuum RECC in Near-Relativistic Collisions

M. Nofal, S. Hagmann, Th. Stöhlker ,D. Jakubassa-Amundsen, C. Kozhuharov, R. Moshammer, J. Ullrich, A. Gumberidze,U. Spillmann, R. Reuschl, S. Heß, S.Trotsenko, D. Banas, F. Bosch, D. Liesen,H. Rothard , R. Dörner, Max Planck Institut für Kernphysik, Heidelberg, GSI, Darmstadt, Inst. f. Kernphysik, Univ. Frankfurt, 4 Mathematisches Institut der LMU München , CIRIL-Ganil,Caen,France Swift heavy-ion collisions offer a powerful tool to investigate a number of fundamental processes, e.g. REC/ photoionization (PI) [1] and (e,2e) for highly charged ions [2] in configurations which are not accessible otherwise. We have recently shown that the short wavelength limit of electron-nucleus bremsstrahlung (BS) [3] can be studied in a unique fashion by measuring differential cross sections for the radiative electron capture (RECC) into the projectile continuum in near relativistic collisions of highly charged ions with atoms [4]. In the projectile frame the RECC is the kinematic inverse of the electronnucleus bremsstrahlung at the short wavelength limit (SWL) [5]: a quasifree electron from the target is decelerated from velocity vproj to v≈0 while emitting a photon of energy Ex= (γ-1)mc. Fano and Pratt [6,7] emphasize that the short wavelength limit of BS is very closely related to PI and may serve as precision probe for the active electron's wavefunction in the extreme E-fields in the immediate vicinity of the nucleus.