Authors: Simeonov, L.I.
Reference: Proceedings of the Nat.Conf. with Intern.Part.:
ELECTRONICA`98, Botevgrad, 96-101,1998.
Abstract:
Presented are experimental results from laboratory durability
tests of microchannel plates. The tests were carried out for design
purposes of the chevron detectors for registration of secondary electron
emission from the carbon foil and the solid-state detector on STOF
sensor of CELIAS on SOHO. The main task was to determine the function of
performance stability of amplification in a long-term test. The
experimental setup allow investigation of the individual performance of
different regions of the microchannel plate by blinding by choice of 15
of the 4x4 pixels, while irradiating the surface with a stable Fe55
source. The duration of the test cycle was 9000 minutes. Some of the
prototypes showed a considerable drop of the amplification after the
first 500 minutes and stabilization at the new low level. This kind of
performance indicates a clear initial degradation of the microchannel
surface, which is difficult to correct via ground command in a real
experiment in space. Most of the prototypes showed a satisfactory
stability over the test period.