James1d ago

#Radiation measurements on a recent #flight I was on, it is interesting to see that immediately after takeoff, the rate drops significantly and only goes up higher again once you gain altitude. I guess it's due to the proximity to the ground and all that concrete and #rock #geology near the surface and then the #CosmicRays in the upper #atmosphere.

There was one #HighEnergy event on the next flight. Probably due to a cosmic ray.

#radiacode #science #chart #measurement #physics

Show threadThree plus or minus five1d ago
@LostGuppy
I’d be thinking it was an environmental effect, like cabin pressure. If you are using a PMT or Geiger those can be affected by lots of things…
Show threadJames1d ago
@ThreeSigma Radiacode sensors (scintillation detectors) are not directly affected by air pressure changes, as they are solid-state, not gas-filled tubes like traditional Geiger counters. 
Show threadThree plus or minus five
@LostGuppy
Website describes their scintillator, but not their readout. Given the form factor, I guess they're likely using an APD. Those won't have a huge vibration or electrical sensitivity the way PMTs do. But I also just doubt that the air providing a lot of shielding for high-energy gammas from the ground. Maybe the tarmac is especially 'hot'?
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