Bonn 2010 – wissenschaftliches Programm
HK 36.29: Poster
Mittwoch, 17. März 2010, 14:00–16:00, HG Aula
Upper limit of 83Rb release into the gas phase from a 83mKr calibration source for the XENON project — Elena Aprile1, Francesco Arneodo2, Laura Baudis3, Marcus Beck4, Alfredo D. Ferella3, Karl Giboni1, Volker Hannen4, •Karen Hugenberg4, Raphael F. Lang1, Ondrej Lebeda5, Antonin Spalek5, Drahos Venos5, and Christian Weinheimer4 — 1Columbia University, USA — 2Gran Sasso National Laboratory LNGS, Italy — 3Zurich University, Switzerland — 4Institut für Kernphysik, WWU Münster, Germany — 5Nuclear Physics Institute, ASCR, Rez, Czech Republic
The isomer 83mKr with its half-life of 1.83 h is an ideal calibration source for a liquid noble gas dark matter experiment like the XENON project. For such a low counting experiment the possibility that traces of the much longer living mother isotop 83Rb (t1/2 = 86.2 d) contaminate the detector must be avoided. In this work the 83Rb release of a 1.8 MBq strong 83Rb source embedded in zeolite spheres has been investigated by searching for the characteristic 83Rb γ lines with the ultra-sensitive germanium detector Gator at LNGS after collecting a possible 83Rb release in a cryogenic trap for about 10 days. No signal has been found. The corresponding upper limit for the 83Rb release of 200 µBq means, that such a 83Rb source as 83mKr generator can be used at the XENON project as well as for the KATRIN experiment. The germanium detector also allowed to set upper limits on the possible release of the isotopes 84Rb and 86Rb, which were produced during the 83Rb production at the Rez cyclotron to some amount.