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Register a new userCompact vacuum phototriodes for operation in strong magnetic field
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The results of tests of 1 vacuum phototriodes in a magnetic field up to 4.5 T are presented. It was found that output amplitude decreases by about 6 % per tesla in the magnetic field range from 2.0 to 4.0 T. For devices with an anode mesh pitch of 16$mu$m, the output amplitude at 4.0 T is 30 % lower than that at zero field.
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In this paper we describe the technology of building a vacuum-tight high voltage feedthrough which is able to operate at voltages up to 30 kV. The feedthrough has a coaxial structure with a grounded sheath which makes it capable to lead high voltage potentials into cryogenic liquids, without risk of surface discharges in the gas phase above the liquid level. The feedthrough is designed to be used in ionization detectors, based on liquefied noble gases, such as Argon or Xenon.
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