SU616534A1 - Method of selecting photoelectronic multipliers for registering weak light fluxes in single-electron mode - Google Patents

Description

This invention relates to photometry and can be used in spectroscopy, astronomy, nuclear physics, etc.

A known method for selecting photomultiplier tubes (PMT) for recording weak "ketov streams according to their electronic characteristics. The method is characterized by the absence of quantitative criteria for the quality of the PMT.

There is also known a method for selecting a photomultiplier for detecting weak light fluxes in a single-electron mode, which includes a preliminary training of a photomultiplier under voltage in the dark.

The reliability of this method is very low because the method does not take into account such characteristics of the photomultiplier as the spectral function of the photocathode, the shape of the single-electromotive angle and the darkness and load.

The invention is an increase in the credibility of the PMT selection method,

This is achieved by the fact that the ndcne of the photomultiplier training measures the single-ectronic distribution of dark amplitudes in amplitude and illuminates the photocathode mono. chromatic light emission, measure the single-electron amplitude distribution of the photopulses, calculate the numerical criterion

4 (w ".v

1/2

..with

B

ft. ".soi,)

Vm amplitude one-electron

where is the pulse voltage of the PMT}

Mf | OL - single-electron distribution of photopulses over amplude when illuminating the photocathode with monochromatic light-inguing}

ti- (od) t: the distribution of the tempo impuses by amplitude;

and according to its value the ruling on the PMT | PMTs are considered ideal. 361 The essential difference between the proposed method and the known one consists in the presence of successive operations: measuring the dark-pulsed amplitude of the dark pulses by amplitude, illuminating the photocathode with monochromatic light, and using one-time illumination of one's weights. , Is the most qualitative criterion for the quality of a PMT operating in one-electron mode after a training operation EI in the dark under stress. Using the quantitative criterion of the suitability of a single-electron photomultiplier for recording weak expression fluxes allows one to take into account the basis of the characteristics of the photomultiplier, its integral quality. Namely: with the spectral sensitivity of the photocattop, the shape of the single-electron distribution of dark pulses, the integral intensity of the new ones, PMT pulses. In the drawing a block diagram of an apparatus for carrying out the method is given. The device contains a monochromatic light source and a source of light 1, a light source 2, a light-emitter 3, a photomultiplier under study, a high-voltage power supply unit 5 of the photomultiplier, a pulse amplifier 7, a multichannel pulse amplitude analyzer 8, a digital computer 9 in Dicatf 1O. The method of selecting a photomultiplier for detecting weak light fluxes into a single electron. The number is realized in the following way. Light attenuator 2 is set to the 100% attenuation position. This is my occult secular use of the pulses from source 1, completely nosv О 1 1 ос ос ос н ntv Л 2, не not: go to the beam splitter 3 on the photocathode using PMT PMT 4, which is derived from HIGH VOLUME, ANGULA, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I will be able to go at the output of the PMT 4 npecgrTct jnoT, you will give the following questions about how to connect the PMCs to the Chesh Chests (first time in amplitude, 1x the first time for the PMT under the PMC under the PMCS on the PMC under the PMC to connect the PMT under the MSC of the PMC to the scam of the PMT, see Training is carried out at a higher rate of each other, according to the family, at 1 WTF, you can use the FEP to learn more about your needs. A differential one-electron distribution of dark pulses in amplitude is obtained at its output. Numerical data are fed to computer 9 and recorded in its memory. Computer 9 and an amplitude of 1 pulses by means of a multichannel analyzer 8 have been reversed so that It would be worthwhile at the output of the multichannel analyzer of the amplitude of the pulses the differential, single-electron distribution of the dark pulses over the amillite with a predetermined accuracy, especially in channels with a large order). Light attenuator 2 is switched to the transmission position. In this case, monochromatic light radiation from source 1 passes through oSpabite 2 light radiation and divides into two equal parts with a splitter 3. One half of the light flux is measured with a calibrated radiometer 6, the other under the photocathode of the photomultiplier under investigation 4, At the output of the PM, a drug photons and photon-4 pulses, one-electron distribution in amplitude of which differs from the one of the electron distributors of dark pulses. Both dark and photo-pulses amplify the amplitude of the pulse body t7 with amplitude and and the entrance of the vehicle to the analyst is 8 amplJytydy. At the output of this anapa gation, one obtains a differential electron distribution of the mixture of themes} {OBI1x and photo power on ashpude. Numeric data is served in the SPM and; evl will be remembered in her memory. Between the computer 9 and the multichannel anashsetiator, the amplitude of the pulses was fed back so as to obtain at the output of the multichannel pulse amplitude analyzer a differential single-path1 CM & GVI dark and photopulse pulse amplitude with a given accuracy (in particular, in the case channels, in this case, in the case of the case channels, in this case, in the case of the case, in this case, in the case of the X-ray channels, and in the case of the X-ray channels, in the case of the X-ray clocks, and in the case of the X-ray channels, in the case of the X-ray channels, and in the case of the X-ray channels, the pulse and amplitude amplitudes of the pulses dkoyem number). Further operations produces M 9: subtracts the differential and single-electron and the dark mixture raopredepeni fotoimlulsov amplitude differential-electron .raspredelenie dark pulses, thereby obtaining a differential-electron distribution pho toimpupos e amplitude but upon illumination with monochromatic light PMT photocathode zhym nalucheniem then squares the obtained one-electron distribution photopulse amplitude with 561 illumination of the photocathode of the PMT with monochromatic light puff Niemi ;, divides the resulting dependence on the differential distribution of the one-electron and the dark mixture fotoimpupsov and numerically integrates the resulting function within channel numbers 8 analiaatora multichannel pulse amplitude. The numerical value of the integral is displayed if | with the indicator 10, the investigated PMTs are ranked by quality in accordance with the digital indicator 1O shown. If necessary, the prediction of the maximum luminous flux intent for the PMT of the PMT is equal to the monochromatic illumination of the photocathode monochromatic and measured, calibrated by the radio address, for | b of the reader with the coil, the expressions pt are captured, where is the assumed value of the extra time (W (1chv (of the filter of the optimal processing system of one electron of a photomultiplier signal, which is usually limited by a temporary neshalom nab; pyudena a. Using the proposed method of selecting a photomultiplier for recording spam light fluxes in one-path {hpp ohm mode, provides high reliability and express speed, as well as a clear physical sense of the quality criterion of a photomultiplier operating in single-mode mode. “Formula of an abbreviation, the selection method of photoelectron multipliers for registering the weak 4 light fluxes in one-electron mode, including the preliminary training of the PMT under Voltage in Femnot characterized in that, in order to increase reliability, after a PMT exercise, the single electron distribution of dark pulses in amplitude is measured, the photocathode is illuminated with monochromatic light radiation, the single electron distribution of photo stimuli in amplitude is measured by counting from the numerical criterion W -1 ((U de - amplitude of single-pulse PMT pulse; “(Qi) one-electron distribution of photo pulses in amplitude when illuminating a photocathode with monochromatic light and scattering; W (U) is the single-electron distribution of dark impulses in a and 1 degree} by its magnitude judging the quality of the photomultiplier, Sources of information, 1 adopted in the schedule during the examination: 1, Anisimova I.I., Gpukhovskry B, M, Photoelectric multipliers. Soviet Adio, M., 1974, p. 41-44. 2, Lomonosov I.I. Kandidatska Dio Sertash, Minsk, BSU, 1066.