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snarkophilus
2006-Jul-14, 01:45 AM
Idly curious, and too lazy (does that make me a laser?) to look it up myself... does anyone know if there are systems in space (stars, star forming regions, shock fronts, et cetera) where stimulated emission is the dominant (or even a significant) radiative process? If so, what are they called and where can I learn more?

trinitree88
2006-Jul-14, 02:54 AM
Idly curious, and too lazy (does that make me a laser?) to look it up myself... does anyone know if there are systems in space (stars, star forming regions, shock fronts, et cetera) where stimulated emission is the dominant (or even a significant) radiative process? If so, what are they called and where can I learn more?

Snarkophilus. You can look up hydroxyl masers...microwave amplification by stimulated emission of radiation...MASER. James Moran of the Harvard Smithsonian Center for Astrophysics specializes in them. His cv reads like Who's Who in radio astronomy. Hydroxyl is the OH- radical from dissociated water molecules. They become pumped into a classic population inversion...and mase. "Fountains" of masing hydroxyl are seen. Jim is one of the worlds leading microwave astronomy gurus. I have had discussions with him in his Cambridge office after an intro by way of his former MIT colleagues. Very gracious, knowledgeable...and liked most of my ideas. He was particulary interested in the CMB..Local Bubble..foreground calculations, and Dwek's dust emissions.
Try http:www.NASA Astrophysics Database Search References. masers ...you'll be buried with good "stuff". Ciao. Pete.

yuzuha
2006-Jul-14, 11:14 AM
Think eta carinae is lasing in the optical region and parts of the crab nebula may be playing free electron laser.

snarkophilus
2006-Jul-15, 07:00 AM
Cool. Thanks, guys. This will keep me up all weekend. :)

trinitree88
2006-Jul-17, 10:42 AM
Cool. Thanks, guys. This will keep me up all weekend. :)

snarkophilus. You're welcome. NASA Astrophysics Database is the real fountain of knowledge for any topic in several fields..physics, geophysics, astrophysics....as is Arxiv, in it.
One of the things you learn is that nobody goes back to black out things published...later found to be untrue. So that can be a little tricky. Also of help is Science Citation Index....how many times has a particular paper been cited for relevance in other papers. This too, has it's Achilles heel....relevant papers get cited by many independent authors, but there are no rules against continuing your research in a thought train, and self-citing previous work. There are more than a few who predominantly self-cite to help their SCI rating....but, to be fair even the very best, (the late John Bahcall) self-cited a lot.
Good luck with your interest in stimulated emission. Pete.