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There's a short fictional account of a science teacher constructing a gold leaf electroscope using stuff in the school, and plaster dug out of the wall of the classroom to help map radioactivity after a limited-strike nuclear war, in "Warday" by Whitley Strieber & James Kunetka. (at least one of these authors has a bit of a nutty back-story, It's important to remember the book lies solidly in the realms of fiction)

I always thought it was somewhat fantastical. I'm rather delighted they could have beaded some polystyrene and stuck it in a cup for much the same effect.

Several SF novels mention using scintillation plastic. Is that also simply fantasy, or are there passive scintillation meters which could in fact detect levels of radioactivity? The 1900s models demanded 20 minutes of acclimatisation inside a dark chamber and were notoriously hard to use. Rutherford refused to use a counter while he could show his trained workers (women mainly) were as accurate. Those counters were photomultiplier tubes. I think quite a lot of the tech here was a precursor to TV, and ultimately the CCD in some ways.

Filmstrip exposure would tell you about a lethal dose, after the event. Helpful for budding scientists if they have enough lab rats to send out with a chunk of film in a wrapper.




Scintillation plastic is very much a thing. Big accelerators, like CERN or Fermilab, used to use long, floppy strips of plastic attached to a photomultiplier tube, which goes to the counters. I believe they still use scintillator detectors farther from the collision region, but the trend has been to move towards silicon pixel detectors closer in.

One thing with scintillators though: You're typically detecting a few photons at a time, so a photomultiplier tube (PMT) is really required for any kind of reasonable SNR with any kind of reasonable temporal resolution.

> Those counters were photomultiplier tubes.

A PMT is actually not a counter (but they are normally used with a counter). It's just a transducer that produces electrical charge at the output in response to photons at the input.

Normally the PMT is connected to a "discriminator" (very fast voltage threshold detector, with adjustable threshold(s)) which takes the very narrow pulses (~2-3 ns) from the PMT and stretches them into pulses with fixed rise time, width and voltage. Those pulses are then counted using whatever hardware you can dream up.

A PMT is really just an electron multiplier with a photocathode in front, so you have all the same issues as you do with electron multipliers and thus use a discriminator for all the same reasons (mainly to remove "runt pulses" that didn't originate from a photon at the input window). Normally you'd use a single level discriminator, but "multi-channel" ones exist also.

Having an adjustable threshold on the discriminator is important to maximize SNR because the electron multiplier within the PMT will wear out and produce smaller pulses, and there can be significant variation in pulse size across serial numbers.

> Rutherford refused to use a counter while he could show his trained workers (women mainly) were as accurate.

I'm skeptical of this account, and the only thing I can find with a quick Google is that Rutherford hired women to count scintillation events because he could pay them less than men(-counters).


Polyvinyl toluene is scintillation plastic.


Not the same thing, but had me remembering the "official" way of disposing of toluene after Chemistry lab in my US High School.

Carefully carry it to the window overlooking the lower roof. Toss it on the roof. Let it evaporate.


We poured ours down the drain.


Sounds like youre looking for the Kearny Fallout Meter:

https://en.wikipedia.org/wiki/Kearny_fallout_meter




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