Preferred Label : photomultiplier tube;
IUPAC acronym : CEM;
IUPAC definition : A vacuum phototube with additional amplification by electron multiplication. It consists
of a photocathode, a series of dynodes, called a dynode chain on which a secondary-electron
multiplication process occurs, and an anode. According to the desired response time,
transit time, time spread, gain, or low dark current, different types of dynode structures
have been developed, e.g. circular cage structure, linear focused structure, venetian
blind structure, box and grid structure. Some special dynode structures permit combination
with additional electric or magnetic fields. A strip dynode photomultiplier tube consists
of a photocathode followed by thin dynode material on an insulating substrate. In
a continuous-strip photomultiplier, two strip dynodes are arranged in parallel. A
potential applied to the ends of the two strips produces an electric field across
the continuous strip dynodes, giving rise to electron multiplication along the dynodes.
In a resistance-strip magnetic photomultiplier, a uniform magnetic field is applied
to the planes of the strips, so that the electrons travel in the crossed electric
and magnetic fields. A channel photomultiplier tube photocathode consists of a channel
electron multiplier (CEM) system for the photoelectrons, and an anode to collect the
final electron current. The basic part of the CEM is a tube with a semiconducting
inner surface. In general it is curved in order to inhibit the acceleration of positive
ions towards the photocathode. A number of small channels called microchannels can
be constructed in arrays for imaging applications.;
Origin ID : P04626;
UMLS CUI : C1709530;
Automatic exact mappings (from CISMeF team)
- Currated CISMeF NLP mapping
- False automatic mappings
- See also
- Semantic type(s)
- UMLS correspondences (same concept)
A vacuum phototube with additional amplification by electron multiplication. It consists
of a photocathode, a series of dynodes, called a dynode chain on which a secondary-electron
multiplication process occurs, and an anode. According to the desired response time,
transit time, time spread, gain, or low dark current, different types of dynode structures
have been developed, e.g. circular cage structure, linear focused structure, venetian
blind structure, box and grid structure. Some special dynode structures permit combination
with additional electric or magnetic fields. A strip dynode photomultiplier tube consists
of a photocathode followed by thin dynode material on an insulating substrate. In
a continuous-strip photomultiplier, two strip dynodes are arranged in parallel. A
potential applied to the ends of the two strips produces an electric field across
the continuous strip dynodes, giving rise to electron multiplication along the dynodes.
In a resistance-strip magnetic photomultiplier, a uniform magnetic field is applied
to the planes of the strips, so that the electrons travel in the crossed electric
and magnetic fields. A channel photomultiplier tube photocathode consists of a channel
electron multiplier (CEM) system for the photoelectrons, and an anode to collect the
final electron current. The basic part of the CEM is a tube with a semiconducting
inner surface. In general it is curved in order to inhibit the acceleration of positive
ions towards the photocathode. A number of small channels called microchannels can
be constructed in arrays for imaging applications.
