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There are many different detectors for different radiation,such as NaI,HpGe,CsI for $\gamma$ detection,and ionization chamber,proportional counter,Geiger counter for $\alpha$, $\beta$ detection,but how to select a suitable detector for different radiation?I mean compare between them,what is the advantages and defects of them?

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    $\begingroup$ This might help understand the detectors offered by the industry. reak.bme.hu/Wigner_Course/2004/WignerManuals/Bratislava/… . $\endgroup$
    – anna v
    Nov 1, 2012 at 9:59
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    $\begingroup$ Unlisted detection technologies include, Cerenkov radiation, transition radiation, time projection chambers (both the traditional gas ones and the spiffy new liquid argon ones), plastic scintillators, liquid organic scintillators, cloud and bubble chambers, spark chambers, silicon photodiodes (in multiple classes), and on and on. You can be in this business for years and not really know them all. $\endgroup$ Nov 1, 2012 at 12:47

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In some sense the question is simple too big. I mean, it always comes down to a balance between your ultimate goal, your budget and any engineering constraints imposed by the goal.

Consider the differences between

  • a personal dose monitor (film badge, TLD, leaf electroscope...) which must be small and light enough to clip onto your person and can't run out of batteries either.
  • a survey meter used for checking the degree of radioactivation of material proposed for removal from a controled area (reactor facility, or whatever)
  • a combined PET/fMRI scanner (these are available now, but the expense in painful)
  • a visible cosmic ray demo for a museum
  • a in-the-hole device for a oil drilling company use to for understanding the geology under their feet

all the way up to things like

  • a ground station for a UHE cosmic ray experiment
  • a neutrino oscillation experiment
  • a collider experiment detector package

Like any other engineering situation we trade things off in order to get what we need (and maybe some of what we want) as easily as possible. In each case we consider things like

  • the range and energy of the radiation to be detected (you can't bury a alpha detection element behind in a sealed, rugged case, because the particles will range out before they get there)
  • the size of the detector elements (and the size of the readout equipment which may be separate) and their arrangement relative each other, the source and other bits which
  • the sensitivity and efficiency needs (to different kinds of radiation, to different energies that might be present)
  • Cost, cost, cost. Some of this kit can be very, very expensive, and you might choose a not-quite-the-best choice if you already have it and the necessary readout gear sitting around the lab from a old experiment. This is the equivalent of a "Don't laugh it's paid for" bumper sticker.
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  • $\begingroup$ Excellent answer. I am a "measurements specialist" in the Material Control and Accountability group on a fuel processing plant, we have three people in our group whose sole job is making these kinds of determinations for just our one plant and the few isotopes of concern. $\endgroup$ Nov 1, 2012 at 13:21
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Generally scintillation detector is used in the detection and measurement of gamma, beta and alpha activity. However, scintillator kept above the photomultiplier tube within the sealed detector differs in each case.

  1. NaI (Tl) crystal is fitted above the photomultiplier tube for gamma detection.
  2. Plastic scintillator is fitted above the photomultiplier tube for beta detection.
  3. ZnS(Ag) is is fitted above the photomultiplier tube for alpha detection.
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  • $\begingroup$ This is also unduly simplified. We use plastic scintillator hodoscopes for gamma detection quite often when we only care about getting their direction (rather than calorimetry) simply because they are inexpensive ad can cover large areas. Nor are we restricted to scintillation: solid state detectors are very popular these days because of their small form factors and modest HV requirements. They are also exceeding good for modest energy alphas as many of them require no windows. $\endgroup$ Sep 5, 2013 at 5:24

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