http://arxiv.org/abs/1611.09712
We present the design and noise performance of a fully cryogenic (T=4 K) HEMT-based charge amplifier for readout of massive semiconductor dark matter detectors operating at sub-Kelvin temperatures. The amplifier has been developed to allow direct detection experiments such as CDMS and EDELWEISS to probe WIMP masses below 10 GeV/$c^2$ while retaining electromagnetic background discrimination. The amplifier dissipates only 1 mW of power and has a measured noise performance three times better than traditional JFET-based charge amplifiers. The predicted optimal filter baseline ionization energy resolution using the measured intrinsic amplifier noise performance and typical detector characteristics is $\sigma_E \approx 100 \,\text{eV}_{ee}$ (33 electrons). We have measured a calibrated baseline energy resolution of $\sigma_E = 91\,\text{eV}_{ee}$ when coupled to a live CDMS II detector. To our knowledge, this is the best resolution achieved on such massive ($\approx$150 pF capacitance) radiation detectors.
A. Phipps, A. Juillard, B. Sadoulet, et. al.
Wed, 30 Nov 16
30/69
Comments: Submitted to JINST
You must be logged in to post a comment.