Nuclear Particle Spectrometers for Satellites and Space Probes

Abstract

A series of particle detectors have been used by the University of Chicago in the cosmic ray research program. The first of the series used a grouping of seven methane-argon semiproportional counters. Of the two balloon-borne spectrometers one used a thin (0.358 gms-cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> ) and a thick (13.53 gms-cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> ) CsI(Tl) scintillator and the associated photomultiplier tubes, while the other used a thin CsI(Tl) (0.716 gms-cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> ) scintillator and a Cerenkov counter (1/2-in. thick lucite) with their associated photomultiplier tubes. The first of these spectrometers was used to obtain the cosmic ray spectrum over the charge range of 6 ≤ Z ≤ 26 and the energy range of 50 to 500 Mev/ nucleon while the second spectrometer was used over the same charge range but the energy range was from 400 Mev/nucleon to 10 Bev/nucleon. The Mariner A spectrometer is similar in principle to the low energy balloon-borne spectrometer but it operated over a slightly different energy and charge range. The charge range was Li, Be, B, C, N, and O, while the energy range was from 44 to 112 Mev/nucleon for Li <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">7</sub> and from 23.1 to 220 Mev/nucleon for O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">16</sub> . The Mariner instrument uses a gold-silicon diode to provide -(dE/dx) information and it uses a photodiode to detect light pulses from the thick CsI(Tl) s cintillator.