Cs feed tests and emittance measurements on a modified MC-SNICS ion source for radiocarbon AMS
Citable URI
https://hdl.handle.net/1912/4389Abstract
We report on 2 recent developments in an ongoing program of characterizing and improving the National
Electrostatics Corp. (NEC) MC-SNICS ion source at University of California (UC) Irvine’s Keck AMS laboratory. First, we
have investigated the possibility of modifying a large-body (134-sample) MC-SNICS to incorporate the UC Irvine Cs oven
and vacuum-insulated Cs feed tube, which provide better confinement of Cs than the standard NEC setup. In our 40-sample
source, the feed tube enters the source housing directly below the ionizer assembly. This area cannot be accessed for machining
on the 134-sample source, but we have successfully tested a modified geometry where the delivery tube enters the body
via the source end flange. Second, we recently installed a second beam profile monitor in the injection line of our spectrometer
to allow us to make online emittance measurements. At full output (150 μA of C– at 55 keV), the emittance of our source
at 8 kV sputtering voltage is approximately 40π mm mrad.
Description
Author Posting. © Arizona Board of Regents on behalf of the University of Arizona, 2007. This article is posted here by permission of Dept. of Geosciences, University of Arizona for personal use, not for redistribution. The definitive version was published in Radiocarbon 49 (2007): 301-306.