Hello from Southern California!

[KailieNadine]

Hi, I'm a physics student at a community college in California. I am working on a research project that is investigating the charge contribution of muons in certain materials, which has naturally led us to starting to build muon detectors. In the process I have also become quite curious about other types of detectors, so I am here to learn more.

[iRad]

Hi Kailie - Hope this site is able to broaden your curiosity of charged particles and deepen your understanding of the world of physics. We look forward to your contributions. Cheers, Tom

[Sesselmann]

Hi Kailie,

Welcome to the forum. I hope you find the information you are seeking and I hope you share your own experiments and findinga s well. It sounds interesting.

Steven

[ColoRad-o]

Hi Kailie,
Welcome! If you follow the links to "Advanced search" you can pull up SOME information about detecting muons. I'm curious about how muons can contribute charge in some materials--do you mean that they IONIZE atoms in the materials and this is collected by a detector? (They lose lots of energy in transit, because muons from the top of the atmosphere are produced with tremendous energies, in the GeV range.) They don't give rise to sharp features, as do gamma rays from decays of unstable nuclei. As a result how much energy they lose (and is there to be detected) is directly proportional to their path length, and end up usually being higher than ordinary gamma ray detectors can easily measure. Best wishes in your work.

[KailieNadine]

Hi Kailie,
Welcome! If you follow the links to "Advanced search" you can pull up SOME information about detecting muons. I'm curious about how muons can contribute charge in some materials--do you mean that they IONIZE atoms in the materials and this is collected by a detector? (They lose lots of energy in transit, because muons from the top of the atmosphere are produced with tremendous energies, in the GeV range.) They don't give rise to sharp features, as do gamma rays from decays of unstable nuclei. As a result how much energy they lose (and is there to be detected) is directly proportional to their path length, and end up usually being higher than ordinary gamma ray detectors can easily measure. Best wishes in your work.

What we are focusing on is how they might affect material (specifically, highly disordered insulating polymers used on spacecraft) charging/discharging during testing. For example, during electron irradiation/cathodoluminescence tests, some of these materials will exhibit occasional strong increases in radiance and current after they have been irradiated for some time, which we think might be the result of a muon passing through the sample and exciting trapped electrons. The plan is to create a large grid of muon detectors around the test chamber, with the goal of establishing whether muon detection is coincident with these charge events, and if they are coincident, to hopefully determine the events' dependence on angle, rate, and energies of the incident muons. We have only been working on this for about 3 months now, so are not too far along yet; still very much working out the ideal detector and grid design, along with some computer simulations/mathematical models.

[ColoRad-o]

Kailie,
Thanks for the explanation!

This sounds a lot like thermoluminescence. In the context of archaeology, for example, ceramics used for pots are of course baked when they are made. Thereafter, they absorb background radiation over centuries. Because many ceramics are non-crystalline, they have lots of "traps" for electrons which were promoted out of whatever states they were in. Often such states are metastable but with very long lifetimes--archaeological times. So one generally makes a very carefully prepared sample (often from gentle grinding of the original ceramic) and then runs it through a temperature cycle, looking for the number of photons (and maybe their energy too) as the sample heats up and releases electrons from their traps, emitting light. Presumably no traps are occupied after this "anneal", depending on the temperature range used. Generally you have to calibrate the *sensitivity* of the material to radiation in order to use it for dating--you have to expose it to a calibration dose (often of X rays) and re-run the annealing process. From a known dose of X-rays you can deduce the approximate dose the original sample had been exposed to, and from the background radiation rate you can deduce how long the sample was exposed, hence the date from the ceramics original manufacture. (This is MUCH less refined than radiocarbon dating, however.)

It sounds like you'd be looking at fairly deep traps--see the estimates I made of energy deposited per unit length by typical muons, which in a scintillator like NaI is in the ballpark of 10-25 MeV.