1、Recognized as anAmerican National Standard (ANSI)Copyright 1972 byThe Institute of Electrical and Electronics Engineers, Inc.345 East 47th Street, New York, NY 10017-2394, USANo part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior
2、written per-mission of the publisher.ANSI/IEEE Std 398-1972(R2006)IEEE Standard Test Procedures for Photomultipliers for ScintillationCounting and Glossary for ScintillationCounting FieldSecretariat for American National Standards Committee N42Institute of Electrical and Electronics EngineersSponsor
3、Nuclear Instumentation and Detectors Committeeof theIEEE Nuclear Science GroupReaffirmed 13 January 2000Approved 28 April 1972American National Standards InstituteReaffirmed 30 March 2006Approved 21 March 1972IEEE-SA Standards BoardiiAmerican National StandardAn American National Standard implies a
4、consensus of those substantially concerned with its scope and provisions.An American National Standard is intended as a guide to aid the manufacturer, the consumer, and the general public.The existence of an American National Standard does not in any respect preclude anyone, whether he has approved
5、thestandard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures notconforming to the standard. American National Standards are subject to periodic review and users are cautioned toobtain the latest editions.CAUTION NOTICE: This American National Standard ma
6、y be revised or withdrawn at any time. The procedures ofthe American National Standards Institute require that action be taken to reafrm, revise, or withdraw this standard nolater than ve years from the date of publication. Purchasers of American National Standards may receive currentinformation on
7、all standards by calling or writing the American National Standards Institute.iiiForeword(This Foreword is not a part of IEEE Std 398-1972, Test Procedures for Photomultipliers for Scintillation Counting and Glossary forScintillation Counting Field, ANSI N42.9-1972.)Photomultipliers are extensively
8、used in scintillation counting for the detection and analysis of ionizing radiation. Theutilization of these detectors in a variety of technical disciplines have made standard test procedures desirable so thatmeasurements may have the same meaning to all manufacturers and users.This standard is not
9、intended to imply that all tests and procedures described herein are mandatory for everyapplication, but only that such tests as are carried out on photomultipliers for scintillation and Cerenkov countingshould be performed in accordance with the procedures given in this document.This publication wa
10、s prepared by the Nuclear Instruments and Detectors Committee of the IEEE Nuclear ScienceGroup:G. L. Miller, Chair Louis Costrell, Secretary R. K. AbeleJ. L. BlankenshipW. L. BrownR. L. ButenhoffJ. A. ColemanD.C. CookF.S. GouldingT.R. KohlerH.R. KrallW.W. ManaganH.M. MannD.E. PersykW.G. SpearJ.H. Tr
11、ainorS. WagnerF.J. WalterH.R. WassonA.L. WhetstoneProject leaders for the development of this IEEE Standard were:D. E. Persyk H.R. KrallAt the time it approved this standard, the American National Standards Committee N42 on Radiation Instrumentationhad the following personnel:Louis Costrell, Chair D
12、avid C. Cook, Recording SecretarySava I. Sherr, Executive SecretaryAmerican Chemical Society.Louis P. Remsberg, JrAmerican Conference of Governmental Industrial HygienistsJesse LiebermanAmerican Industrial Hygiene Association .W. H. RayAmerican Nuclear Society W. C. LipinskiThomas Mulcahey (Alt)Amer
13、ican Society of Mechanical Engineers.R. C. AustinAmerican Society of Safety Engineers .(Representation Vacant)American Society for Testing and MaterialsJohn L. KuranzJack Bystrom (Alt)Atomic Industrial Forum.(Representation Vacant)Electric Light and Power Group G. S. KeeleyG. A. Olson (Alt)Health Ph
14、ysics Society. J. B. Horner KuperRobert L. Butenhoff (Alt)Institute of Electrical and Electronics Engineers .Louis CostrellLester Kornblith, JrP. J. SpurginJ. Forster (Alt)ivInstrument Society of America . M.T. SlindJ. E. Kaveckis (Alt)Manufacturing Chemists Association . Mont G. MasonNational Elect
15、rical Manufacturers Association Theodore HamburgerOak Ridge National Laboratory. Frank W. ManningScientic Apparatus Makers Association Robert BreenUnderwriters Laboratories.Leonard HornU.S. Atomic Energy Commission, Division of Biology and Medicine .Hodge R. WassonU.S. Atomic Energy Commission, Divi
16、sion of Reactor Development and Technology . Paul L. HavensteinW. E. Womac (Alt)U.S. Department of the Army, Materiel Command .Abraham E. CohenU.S. Department of the Army, Ofce of Civil Defense Mobilization Carl R. Siebentritt, JrT. G. Provenzano (Alt)U.S. Department of Commerce, National Bureau of
17、Standards Louis CostrellU.S. Department of Health, Education, and Welfare Public Health Service Henry J. L. Rechen, JrRoger Schneider (Alt)U.S. Naval Research Laboratory. D.C. CookMembers-at-Large.J. G. BellianO. W. BilharzS. H. HanauerJohn M. Gallagher, JrVoss A. MooreR. F. SheavWhen the IEEE Stand
18、ards Committee approved this standard on March 21, 1972, it had the following membership:J. Forster, Chair B. O. Weinschel, Vice Chair S.I. Sherr, Secretary S. J. AngelloS. AronowJ. AvinsB. B. BarrowF. K. BeckerR. BreretonW. H. CookL. CostrellG.E. HertigJ.L. KoepfingerH. LanceB.J. LeonD.T. MichaelJ.
19、D.M. PhelpsR.H. Rose, IIS.W. RosenthalG. ShapiroR.M. ShowersP.H. SmithF.G. TimmelL. van RooijR.V. WachterW.T. WintringhamviCLAUSE PAGE1. General 11.1 The Scintillation Counter . 11.2 The Cerenkov Counter . 12. Photomultiplier Characteristics.12.1 General Characteristics 12.2 Additional Characteristi
20、cs Specific to Scintillation and Cerenkov Counters 23. Testing of Photomultiplier Characteristics .23.1 Pulse-Height Characteristics 23.2 Spurious-Pulse Characteristics. 93.3 Pulse Timing Characteristics . 93.4 Measurement Techniques 114. Test Conditions for Photomultipliers205. Test Instrumentation
21、 .206. Glossary for Scintillation Counting Field .217. Common Acronyms 27Copyright 1972 IEEE All Rights Reserved1An American National StandardIEEE Standard Test Procedures for Photomultipliers for Scintillation Counting and Glossary for Scintillation Counting Field1. GeneralThe photomultiplier is an
22、 essential component in scintillation and Cerenkov counting. In these applications there arespecial requirements with regard to pulse-height characteristics, spurious pulses, and timing.1.1 The Scintillation CounterThe scintillation counter is a radiation detector that consists of three major compon
23、ents: a scintillating medium thatproduces a ash of light when ionizing radiation interacts with it; one or more photomultipliers, optically coupled tothe scintillator, which converts the light ash to an amplied electrical impulse; and associated electronicinstrumentation which powers the photomultip
24、lier and processes the output signal.1.2 The Cerenkov CounterThe Cerenkov counter is a radiation detector that consists of three major parts: a medium in which light is produced bythe Cerenkov effect; one or more photomultipliers, optically coupled to the Cerenkov medium; and the associatedelectroni
25、c instrumentation which powers the photomultiplier and processes the output signal.2. Photomultiplier Characteristics2.1 General CharacteristicsThe tests herein described for photomultipliers to be used in scintillation counters are supplementary to those testsdescribed in IEEE Std 158-1962 , Method
26、s of Testing Electron Tubes, which covers the following basic characteristicscommonly requiring specication for photomultipliers (numbers in brackets refer to section numbers of IEEE Std 158-1962 , Part 5.):Radiant sensitivity 2.4Uniformity of sensitivity 2.7Current amplication 3.2Current-voltage re
27、lationship 4.2Dynamic performance, pulse performance 5.22Copyright 1972 IEEE All Rights ReservedIEEE Std 398-1972 IEEE STANDARD TEST PROCEDURES FOR PHOTOMULTIPLIERS FORElectrode dark current 6Noise 7Peak-output-current limitations 92.2 Additional Characteristics Specific to Scintillation and Cerenko
28、v CountersAdditional specications and tests required for photomultipliers used in scintillation and Cerenkov counting inconnection with the preceding basic characteristics are the following:1) Pulse-height characteristics2) Spurious-pulse characteristics3) Pulse-timing characteristics3. Testing of P
29、hotomultiplier Characteristics3.1 Pulse-Height CharacteristicsThe following sections deal with pulse characteristics of photomultipliers used in counting applications. Throughoutthis section it is assumed that the pulse-height analyzer is linear and that channel numbers are with respect to theextrap
30、olated pulse-height analyzer zero.3.1.1 Pulse Height.A photomultiplier consists of a photocathode which produces photoelectrons and an electron multiplier structurewhich provides gain by secondary electron multiplication. For a given number Nof photoelectrons emitted from thephotocathode, a number G
31、Nelectrons are observed at the anode. The factor Gis the multiplier gain, which dependsupon the interstage potential differences applied to the electrodes. The counting rates and resolving times shall be suchthat pulse pileup is sufciently low so as not to signicantly affect the accuracy of the resu
32、lts.When the input consists of photon packets sufciently well spaced in time, the photomultiplier can resolve them asseparate events, and the output signal consists of separate charge pulses. These pulses can be amplied with a charge-sensitive preamplier, followed by a main amplier, and sorted with
33、a pulse-height analyzer. The term pulse height iscommonly used to designate the charge associated with a PMT (photomultiplier tube) output pulse.Pulse height is measured with a charge-sensitive preamplier and a pulse-height analyzer. The system can becalibrated in terms of coulombs per channel with
34、a precision pulser. The slope and zero intercept shall be determined.3.1.2 Pulse-Height Resolution.A photomultiplier produces a charge output proportional to the number of photons incident on the photocathode.Because of the statistical variations inherent in the conversion of photons to photoelectro
35、ns, together with thestatistical nature of the secondary emission process, the output-signal charge varies from one pulse to the next even forequal numbers of incident photons. The resulting distribution in pulse height limits the photon resolution of the deviceand hence limits the energy resolution
36、 of a scintillator-photomultiplier combination. For this reason a gure of meritcalled PHR (pulse-height resolution) is introduced to characterize the devices ability to discriminate between slightlydifferent input-signal amplitudes.PHR is the fractional full width at half maximum of the pulse-height
37、-distribution curve (FWHM/A1) of the peak ofinterest, where A 1 is the pulse height corresponding to the maximum of the distribution curve. It is customary to statePHR in units of percent. The following discussion outlines several kinds of PHR measurements that are used tocharacterize photomultiplie
38、rs.Copyright 1972 IEEE All Rights Reserved3SCINTILLATION COUNTING AND GLOSSARY FOR SCINTILLATION COUNTING FIELD IEEE Std 398-1972In general there are ve distinct PHR measurements that serve to dene the photon-and-electron resolution ofphotomultipliers and photomultiplier-scintillator combinations.1)
39、137Cs PHR for a Scintillation-Crystal PMT Combination.This PHR is principally a function. of thephotocathode quantum efciency and spatial uniformity, as well as the resolution of the scintillation crystal.2)Light-Emitting Diode PHR.This PHR is obtained with an LED (light-emitting diode) calibrated t
40、o provide a137Cs-equivalent signal (or stated number of photoelectrons per pulse). The LED PHR is numerically smallerthan the scintillator-PMT PHR because the contribution of the crystal is not present. (See Fig. 1.)3)55Fe PHR for a Scintillation-Crystal-PMT Combination. This is the PHR obtained fro
41、m a scintillation crystaland an 55Fe source. This PHR depends on both the crystal and the photomultiplier.4)Single-Electron PHR. The PHR of the SEPHR (single-electron spectrum)has signicance only for thosephotomultipliers that can resolve a single-electron peak. A weak dc light is used as the source
42、 of singleelectrons from the photocathode. (Note that this measures only the resolution of the electron multipliersection of the device.)5)Electron Resolution. Electron resolution is a measure of the ability of the electron multiplier section of thedevice to resolve inputs consisting of either one o
43、r two electrons. The measurement applies only to thosephotomultipliers that can resolve one- and two-electron events. As an alternative to measuring the FWHM ofthe electron peak, the peak-to-valley ratio can be measured. (See Fig. 2.)Measurement of 137Cs PHR requires a 137Cs source, an NaI(T1) scint
44、illation crystal of approximately the samediameter as the photocathode, a pulse-height analyzer, and the photomultiplier to be tested. The PMT is opticallycoupled to the scintillation crystal, for example, with the aid of silicone grease or viscous oil. The crystal housing mustbe at photocathode pot
45、ential. The source is placed in contact with the crystal housing.The PMT should be operated at a voltage such that linear response is obtained; that is, output is proportional to inputintensity. Improper anode bias, excessive gain (and thus excessive anode current), or improper voltage divider circu
46、itsmay give rise to a compression of the output-pulse distribution, yielding an incorrect (low value) of PHR.The scintillation-crystal-PMT combination must operate for several hours to obtain optimum PHR.Phosphorescence of the crystal and PMT faceplate may require several hours to decay to a low eno
47、ugh level to permitaccurate measurements to be made. Therefore, photomultipliers and crystals should not be exposed to ambientlaboratory light for some time before measurements are made.The test enclosure must be designed to avoid high electric elds in the region of the photocathode. If the PMT isop
48、erated at photocathode ground (positive high voltage), there is little problem with external electric elds at thephotocathode. If negative high voltage is used, electric elds near the photocathode must be low. This may beaccomplished by an electrostatic shield having the same potential as the photoc
49、athode. Otherwise, excessive noise onthe output signal and electrolysis, followed by eventual loss of photosensitivity, may develop. As with other PMTmeasurements, a magnetic shield is required.4Copyright 1972 IEEE All Rights ReservedIEEE Std 398-1972 IEEE STANDARD TEST PROCEDURES FOR PHOTOMULTIPLIERS FORFigure 1137Cs Equivalent LED spectrumCopyright 1972 IEEE All Rights Reserved5SCINTILLATION COUNTING AND GLOSSARY FOR SCINTILLATION COUNTING FIELD IEEE Std 398-1972Figure 2Typical Electron Resolution of Photomultiplier Tube Inco
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