Cosmic rays pose dangers to frequent flyers. This radiation detector could help.

[Admin]

Cosmic rays coming from ultrapowerful sources in the distant universe can pose risks to humans on Earth — particularly frequent air travelers, who are routinely exposed at the high altitudes of commercial flights.

Cosmic rays pose dangers to frequent flyers. This radiation detector could help. : Read more

 

[Unclear Engineer]

I have no problem with folks mapping cosmic ray intensties as a function of time over various routes used by passenger aircraft.

But, I find it annoying that people publish articles about it in the popular media without actually specifying any radiation dose information. How about providing:
1. the average estimated total radiation dose to people on the ground;
2. the average radiation dose for a flight from Washington DC to LA on San Francisco;
3. the dose limit that applies to flight crews?

That would provide some useful perspective.

And, additional perspective could be provided by telling us the dose rates in terrestrial hot spots, like the one in India, where the does rate is about 10 times the average dose rate for people around the globe. I have not followed this for decades, but the last I read, health effects were not detected in the populations of those unusually high terrestrial radiation areas.

The media tends to get scary numbers by using statistical analyses that show very low additional dose rates to a very large number of people, and multiply those by very low individual risk numbers gleened from linearly extrapolating the effects of high does toward zero dose rate.

On the other hand, I just needed some medical CAT scans, and they gave my eyes 10 times the allowed annual dose to professionals who are monitored for radiation - coming to 75% of the short-term dose that is deterministically known to cause cataracks with about 8 years of lag time. I was scheduled for more x-rays, but asked to be switched to MRIs instead, because I knew the risk. But, you don't read scare stories in the media about medical sources of radiation.

 

[bernie]

Rather little detail on the detection technique used. I suspect that all is being done is to detect the resulting gamma ray intensity. A much easier thing to do than detect cosmic ray intensity, and not novel. Just take a Geiger counter up with you on your next flight and observe the results. My gamma alarm was set off!! The gamma count was 10 times higher than at sea level.

 

[Unclear Engineer]

By the time the "shower" products of cosmic rays that have interacted with matter reach inside the metal cans we call airplanes, I doubt there are any charged particles left to be absorbed by people, just the high energy photons we call gamma rays.

 

[Atilla De Bum]

Once these highly charged 'heavy particles' interact with the skin of the aircraft, only about 10% of them are actually absorbed in a dire ct collision, giving off a shower of highly ionized particles measurable by a 'dosimeter'. Of the remainder (90%) are effectively 'slowed down' by their ionic-drag of attracted ions in a comet like trail. Dosimeters are historically 'directional' and only show about half of the total dose, that coming from the Effective Aperture of the material used for detection. A thin sheet of film is mostly effective in a direct or perpendicular direction and the efficiency drops off to Zero in a 90 degree collision. Even Thermo Luminescent Devices (TLD's) display this directivity. Hopefully, these newly developed detection devices have a better cross section capture. But what exactly are they capturing? Gamma? High Speed charged ions? If so, what energy ranges?

I've seen nothing in print on these new devices to be able to pass judgement. I've carried film badges and modern TLD's on 24 hour flights both day and night and have only seen less than 1% of an additional dose that I would have seen on the ground. No doubt, my devices were not very efficient or accurate.

 

[Unclear Engineer]

Seems like an old liquid scintillation detector would give the 4 pi detection sensitivity.

Some TLDs I have used were thick crytals, too, so not clear to me that they are not also 4 pi.

But, when looking for cosmic ray dose, it seems that "up" is the prefered direction, anyway.