Laser-stimulated two-step recombination of highly charged ions and electrons in a storage ring

Two-step resonant laser-stimulated recombination of highly charged ions was performed for the first time. Nd:YAG laser pulses overlapped with an Ar[sup 18+] beam in the electron cooler of the ESR storage ring at GSI induced transitions from the continuum to the [ital n]=81 state of hydrogenlike Ar[sup 17+]. To avoid reionization in the bending magnet before reaching the detector, the [ital n]=81 population was transferred to a state well below the reionization threshold by a Ti:sapphire laser. Tuning of this laser yielded the [ital n]=81 to 36 and 37 transition-line profiles. The two-step method provides access to detailed Rydberg spectroscopy in an electron beam environment.

Test of Special Relativity in a Heavy Ion Storage Ring

New access to the magnetic moment distribution in the nucleus by laser spectroscopy of highly charged ions

Abstract The availability of high intensity, high quality beams of highly charged ions has started a new application for laser spectroscopy. High resolution spectroscopy can now be applied to a study of hydrogen-like atomic states in heavy elements. In principal, this will allow a determination of the hyperfine splitting with an accuracy in the 10 −6 -range or better. Presently this exceeds the limits given by the uncertainties of the nuclear quantities, especially the distribution of the nuclear magnetization in the nucleus. Since the new approach can be applied to a family of test cases, it can provide a wide experimental basis for the separation of nuclear and QED effects. This is especi…

Ion beam preparation of 7Li+ for precision experiments at heavy ion storage rings

Abstract Heavy ion storage rings allow for tests of the structure of local space time via the Doppler effect. At the TSR/Heidelberg an experiment with high resolution laser spectroscopy at 7 Li + is performed. To gain the maximum resolution for saturation spectroscopy new methods of relativistic ion beam preparation and diagnostics have been developed. The laser cooling of the beam allows for precision determination of the mean velocity of the ions. A novel phase synchronous detection scheme, ultimately sensitive to single ions, gives insights into the cooling mechanism and dynamics. With an additional synchronous excitation scheme systematic uncertainties of the test experiment can be dras…

Hyperfine measurements in a storage ring

Starting with a look at the outstanding role of the hydrogen atom in modern physics, this work reviews aspects of an extension of precision spectroscopy to the ground-state hyperfine structure of highly charged hydrogenic ions. In this connection, the preferences of heavy-ion storage rings are outlined and illuminated by the laser-spectroscopic measurement (the first of that kind) of the 1s hyperfine splitting of 209Bi82+, stored in the heavy-ion storage ring at GSI. The experimental results, including the mean lifetime of the upper 1s substate, are compared with the presently available theoretical calculations. The relevance of studying further hydrogenicc ions in the vicinity of the doubl…