Radioactive Projectile Excitation Experiments

The Transient Field technique was successfully used to measure the magnetic moment of radioactive 76Kr at Berkeley.
A proposal RIB-112: Measurement of the 2+ state of 132Te produced as radioactive beam was approved and a test experiment was performed in July 2004. A summary of the experiment is provided here . With the lessons learned, a new chamber was installed and the experiment rescheduled for spring 2007. The radioactive beam could not be delivered as scheduled and instead the new setup was tested with stable 130Te. The results of this test are summarized.

The findings are:

Experiment from June 22. to July 3. 2007

Two different targets were used;
1.3 mg/cm2 C on 4.9 mg/cm2 Gd backed by 0.8 mg/cm2 of Cu (added solely to improve thermal conductivity) and
   1 mg/cm2 C on 4.4 mg/cm2 Fe.
Both targets were cooled to 77 K with liquid nitrogen. The coincidence rate was at best 1 every 18 seconds per Clover detector for a total of about 700 counts per Clover and field direction. The data are still being analyzed but the preliminary result g(2+) = +0.3(0.17) is in agreement with Ref. [1]. An important part of this experiment was the determination of the sign of the g factor, which is as expected positive. The success of this experiment provides a proof of principle and is a guide for future measurements. A report can be found in the HRIBF News Letter. The experiment was also reported at the DNP meeting of the APS in October 2007 in Newport News, VA (BAPS Vol. 52, No. 9 October 2007, DA47, HG7).

The final publication can be found in Phys. Lett. B664, 241-245 (2008)

N. J. Stone, A. E. Stuchbery, M. Danchev, J. Pavan, C. Timlin, C. Baktash, C. Barton, J. Beene, N. Benczer-Koller, C. R. Bingham, J. Dupak.  A. Galindo-Uribarri, C. J. Gross, G. Kumbartzki, D. C. Radford, J. R. Stone and N. V. Zamfir, Phys. Rev. Lett. 94, 192501 (2005).

Gerfried Kumbartzki
Last modified: Thu Jan 21 21:21:07 EST 2010