Apparatus for determining the dose equivalent of neutrons

Claim 1

An apparatus for obtaining an indication of the dose equivalent independent of the energy of the neutrons and dose rate equivalent of neutrons without registering any thermal neutrons, which includes in combination: a detector operable to absorb neutrons and to emit voltage pulses, a mantle surrounding said detector having only a single moderator layer for moderating purposes and for absorbing neutrons, amplifying means following and in series with said detector for amplifying the voltage pulses emitted by said detector, a voltage discriminator arranged to receive the amplified voltage pulses, recording means following and arranged in series with said voltage discriminator for registering the time average number of the voltage pulses emitted by said voltage discriminator withholding voltage impulses while said detector for neutrons with energies up to at least 10 6 eV emits voltage pulses the height of which depends both on the energy freed by the nuclear processes initiated by the absorbed neutrons and on the kinetic energy of the absorbed neutrons, and while the number of the voltage pulses with a height located within the range of the energies freed in the nuclear processes is at a maximum, said voltage discriminator having the height of the voltage threshold located above the height of the voltage of the by far greatest number of the voltage pulses distributed about said maximum, that part of said mantle which faces said detector comprising a cadmium layer having a thickness of from 0.1 to 2 millimeters to preclude thermal neutrons.

Claim 2

An apparatus for obtaining an indication of the dose equivalent independent of the energy of the neutrons and dose rate equivalent of neutrons without registering any thermal neutrons, which includes in combination: a detector operable to absorb neutrons and to emit voltage pulses, a mantle surrounding said detector having only a single moderator layer for moderating purposes and for absorbing neutrons, amplifying means following and in series with said detector for amplifying the voltage pulses emitted by said detector, a voltage discriminator arranged to receive the amplified voltage pulses, recording means following and arranged in series with said voltage discriminator for registering the time average number of the voltage pulses emitted by said voltage discriminator withholding voltage impulses while said detector for neutrons with energies up to at least 10 6 eV emits voltage pulses the height of which depends both on the energy freed by the nuclear processes initiated by the absorbed neutrons and on the kinetic energy of the absorbed neutrons, and while the number of the voltage pulses with a height located within the range of the energies freed in the nuclear processes is at a maximum, said voltage discriminator having the height of the voltage threshold located above the height of the voltage of the by far greatest number of the voltage pulses distributed about said maximum, that part of said mantle which faces said detector comprising a cadmium layer having a thickness of from 0.1 to 2 millimeters to preclude thermal neutrons.