Limits on the release of Rb isotopes from a zeolite based 83mKr calibration source for the XENON project

Understand

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.

• However, the risk of contamination of the detector with traces of the much longer lived mother isotop 83Rb (86.2 d half-life) has to be ruled out.
• In this work the release of 83Rb atoms from a 1.8 MBq 83Rb source embedded in zeolite beads has been investigated.
• To do so, a cryogenic trap has been connected to the source for about 10 days, after which it was removed and probed for the strongest 83Rb gamma-rays with an ultra-sensitive Germanium detector.