Balloon Flight Test of a Compton Telescope Based on Scintillators with Silicon Photomultiplier Readouts
P. F. Bloser, J. S. Legere, C. M. Bancroft, J. M. Ryan, M. L. McConnell
(Submitted on 24 Feb 2016)
We present the results of the first high-altitude balloon flight test of a concept for an advanced Compton telescope making use of modern scintillator materials with silicon photomultiplier (SiPM) readouts. There is a need in the fields of high-energy astronomy and solar physics for new medium-energy gamma-ray (~0.4 – 10 MeV) detectors capable of making sensitive observations. A fast scintillator- based Compton telescope with SiPM readouts is a promising solution to this instrumentation challenge, since the fast response of the scintillators permits the rejection of background via time-of-flight (ToF) discrimination. The Solar Compton Telescope (SolCompT) prototype was designed to demonstrate stable performance of this technology under balloon-flight conditions. The SolCompT instrument was a simple two-element Compton telescope, consisting of an approximately one-inch cylindrical stilbene crystal for a scattering detector and a one-inch cubic LaBr3:Ce crystal for a calorimeter detector. Both scintillator detectors were read out by 2 x 2 arrays of Hamamatsu S11828-3344 MPPC devices. Custom front-end electronics provided optimum signal rise time and linearity, and custom power supplies automatically adjusted the SiPM bias voltage to compensate for temperature-induced gain variations. A tagged calibration source, consisting of ~240 nCi of Co-60 embedded in plastic scintillator, was placed in the field of view and provided a known source of gamma rays to measure in flight. The SolCompT balloon payload was launched on 24 August 2014 from Fort Sumner, NM, and spent ~3.75 hours at a float altitude of ~123,000 feet. The instrument performed well throughout the flight. After correcting for small (~10%) residual gain variations, we measured an in-flight ToF resolution of ~760 ps (FWHM). Advanced scintillators with SiPM readouts continue to show great promise for future gamma-ray instruments.
Comments: 39 pages, 25 figures, to appear in NIM-A
Subjects: Instrumentation and Methods for Astrophysics (astro-ph.IM); Instrumentation and Detectors (physics.ins-det)
Journal reference: Nuclear Instruments and Methods in Physics Research A, 812 (2016) 92
DOI: 10.1016/j.nima.2015.12.047
Cite as: arXiv:1602.07581 [astro-ph.IM (or arXiv:1602.07581v1 [astro-ph.IM] for this version)
Submission history
From: Peter Bloser
[v1] Wed, 24 Feb 2016 16:30:49 GMT (2584kb)
http://arxiv.org/abs/1602.07581
