Orbiting Cloud Chamber

[Happablapp]

I've read that cosmic rays are far higher energy than those generated in manmade particle accelerators. Would it be worthwhile to build an orbiting cloud chamber to collect cosmic rays before they impact the Earth's atmosphere? Or would the collision rate be too low to provide statistically sound scientific data?

[ZapperZ]

What kind if information are you expecting to get out of such a cloud chamber? You will note that the detectors that we have at all of these particle colliders (CDF, D0, ATLAS, CMS, etc) are huge, complicated beasts, all to be able to make very precise measurement of various properties of the collision. In other words, they are not simple cloud chamber.

So it isn't just a matter of having a collision, but also a matter of having the right detector to detect as much as possible the result of that collision.

Zz.

[Astronuc]

The Alpha Magnetic Spectrometer Experiment was proposed for the International Space Station, but has been postponed or deferred indefinitely due to the limited budget and problems with Shuttle.

http://ams.cern.ch/

http://ams.cern.ch/AMS/ams01_homepage.html


One objective is to better define the energy spectrum of high energy solar and cosmic particles. Such particles cause spallation reactions in structural materials which greatly increases exposure to astronauts.

[Vanadium 50]

For many years, people flew particle detectors - mostly emulsions - on balloons to do exactly what the OP described. This ended up running out of steam for very high energies for two reasons: one is that the size of the detector grows ~linearly with the energy of the cosmic ray you want to look at, and it gets harder and harder for a balloon to lift it, and you don't know in advance where a high energy collision will occur, so you have to fly for a longer and longer time to get as many as you would like.

As Astronuc pointed out, the last major experiment to be canceled from the ISS was a particle detector.

[D H]

We have some already. The Compton Gamma Ray Observatory (launched 1991, deorbited 2000), International Gamma-Ray Astrophysics Laboratory (launched 2002), Swift Gamma-Ray Burst Mission (launched 2004), Gamma-ray Large Area Space Telescope (launched 2008) are orbiting gamma ray detectors. The Compton Gamma Ray Observatory (launched 1991, deorbited 2000) did exactly that. The CGRO observation of gamma ray burst 990123 helped determine that GRBs are highly collimated explosions.

[Happablapp]

I guess the idea would be to detect the Higgs particle, or find proof for or against superstrings, etc. What energy level would be beyond the capability of any feasible ground-based atom smasher, but still possible with an orbiting cloud chamber?

[Astronuc]

The energies of cosmic rays exceed man-made particle accelerators by several orders of magntiude, i.e. >> 10 TeV.

These particles are known as ultra-high-energy cosmic rays and have energies up to 1020 eV, or 108 TeV.
http://en.wikipedia.org/wiki/Ultra-high-energy_cosmic_ray

[Happablapp]

So they are rare, but they have been detected. Why is there still debate over Higg's particles then? How much better does the observation have to get to these ultra-high energy cosmic rays to resolve the standard model conclusively?

[Vanadium 50]

Most collisions that are energetic enough to produce a Higgs don't. Maybe only one in a billion or a few billion do. So while there is a cosmic ray with the equivalent energy of an LHC collision hitting the earth every few minutes, the actual Higgs production rate is perhaps one per thousand years or so.

Also, the LHC detectors weigh thousand of tons for a reason - you need that level of instrumentation right up to the collision point to tell if it's a Higgs or something else. Nothing nearly that heavy has ever been flown, much less orbited. It wouldn't help if you did - not only do you have the 1000 year problem, you don't know where the cosmic ray is going to hit in time to move your detector into position.

[D H]

So they are rare, but they have been detected. Why is there still debate over Higg's particles then? How much better does the observation have to get to these ultra-high energy cosmic rays to resolve the standard model conclusively?

These ultra-high energy gamma rays are (drum roll please) ultra-high energy gamma rays; i.e. photons. They are not Higgs particles.