DESIGN OF PHOTOMULTIPLIERS FOR THE SUBMILLIMICROSECOND REGION

Journal Article · Mon Dec 01 04:00:00 EST 1958 · IRE Trans. Nuclear Sci.

DOI:https://doi.org/10.1109/TNS2.1958.4315635· OSTI ID:4285540

Morton, G A; Matheson, R M; Greenblatt, M H

In considering the design of a photomultiplier with good time resolution characteristics, it is convenient to divide the problem into two pants, one dealing with the photocathode-to-first dynode region, the other with the secondary emission multiplier structore. The two principal causes of poor time resolution in both of these parts are: (1) the different path lengths of electrons originating from separated points on a second and (2) the effect of initial velocities of the emitted electrons on transit times. The electron optical approach to the alleviation of the transit time spread due to path differences is discussed for both the cathode region and the structore. The focusing spiral method of analyzing the performance of a structore is of considerable value. The effects of initial velocities can be reduced by ensuring that the electron velocities within the photomultiplier are very high. It is not practical to obtain these high velocities simply by applying a high over-all voltage to the tobe because of the loss of secondary emission gain and because of internal and external insulation difficulties. However, the necessary high velocities can be obtained by the use of high voltage field electrodes between successive dynodes, so arranged thot electrons are rapidly accelerated to a high velocity and then decelerated before they reach the next dynode. A photomultiplier is described whose design is based upon these two principles. A high voltage central electrode system between successive dynodes serves to give electrons the high velocity required to minimize transit time spread. Calculated and measured characteristics of this structure are given. When operated in conjunction with suitable circuitry, resolutions of a few micromicroseconds should be obtainable. (auth)

• Research Organization: RCA Labs., Princeton, N.J.
• Sponsoring Organization: USDOE
• NSA Number: NSA-13-003758
• OSTI ID: 4285540
• Journal Information: IRE Trans. Nuclear Sci., Journal Name: IRE Trans. Nuclear Sci. Vol. Vol: NS-5
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

CATHODES
CIRCUITS
CONFIGURATION
DYNODES
EFFICIENCY
ELECTRIC CONDUCTIVITY
ELECTRIC FIELDS
ELECTRIC POTENTIAL
ELECTRODES
ELECTRONS
EMISSION
EQUATIONS
FOCUSING
INSTRUMENTS
LOSSES
MEASURED VALUES
MOTION
NUMERICALS
OPERATION
PERFORMANCE
PHOTOELECTRIC EFFECT
PHOTOMULTIPLIERS
PLANNING
RESOLUTION
SECONDARY EMISSION
VELOCITY