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I know that synchrotron radiation is produced when a charged particle is accelerated radially by a magnetic field, but I was wondering if synchrotron radiation could also be produced by an uncharged particle radially accelerated by a gravitational field?

Or to put it another way: is synchrotron radiation caused by the radial acceleration of a particle, regardless of the source of acceleration?

Jacob
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  • Why would you think that it could be explained that way? – Kyle Kanos Jan 09 '15 at 19:17
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    I don't think OP is suggesting that the synchrotron radiation that we observe is actually gravitational radiating. I think he is asking whether a similar setup with uncharged particles could produce gravitational waves. In that case I don't see any reason why they wouldn't, although the gravitational waves would be incredibly weak. – JotThisDown Jan 09 '15 at 19:53
  • @JedThompson: OP states, "I was wondering if it could also..." where "it" must refer to synchrotron radiation (no other applicable noun). I can see your interpretation, but it would be a poorly worded question in that case. Hopefully OP can clarify on the issue. – Kyle Kanos Jan 09 '15 at 21:37
  • @KyleKanos: I agree with the grammar, but based on the fact that he immediately talks about uncharged particles (which don't produce electromagnetic waves when accelerated), I believe he is referring to the analogous case of gravitational waves. It is a little bit poorly worded though, and a clarification would be great. – JotThisDown Jan 10 '15 at 00:25
  • Similar question about Cherenkov radiation – endolith Jan 15 '16 at 04:11

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I believe that you're essentially asking whether a massive particle orbiting around some gravitational well produces gravitational waves, and the answer in that case is yes. Imagine that you have two massive objects orbiting each other. In this case, the system certainly radiates energy in the form of gravitational waves. Below I have attached a simulated picture of two black holes orbiting each other in two dimensions. The ripples represent the gravitational waves propagating outward. Now take the limit as the mass of one of the black holes grows very large. Now the heavy black hole will barely move and the other one will orbit around it in the same way that a charged particle moves in a synchrotron. Gravitational waves will still be produced.

Of course, it's worth noting that if you tried to do this with small particles, like neutrons, the gravitational waves would be far too weak to detect. You would really need very massive objects orbiting very quickly.

Two black holes orbiting each other

JotThisDown
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Okay, I think I'll answer your question with a paper,

basically I'm doing a dissertation on Gamma Ray Bursts and Gravitational Waves. Look for a paper called 'Gravitational Wave Memory from Gamma Ray Bursts’ Jets'

It's not mine, I'm referencing it. Basically I think the answer is yes. You will get GWs in your direction if a jet from a gamma ray burst is pointed at you, from the acceleration of the matter. However this would be more symptomatic of Mildly relativistic Cyclotron Radiation rather than full on Synchotron, as the gamma factor is about 100-1000. But for massive 300M collapsars maybe. (sorry for all Jargon, but you wanted to know). However this radiation from these GRBs (Mergers or Stellar Collapse), would be masked by the GWs given out by the Burst, as its far greater in energy.

But to answer your q, Yeah I think they are analogous of eachother.

PS, I'm here cos I'm looking for the answer to this myself

  • (a) Don't apologize for jargon, but if you feel strongly about it, perhaps linking to Wikipedia articles on the phrases (b) This seems like an opinion without any facts (c) presenting a link (or simply a title) doesn't usually make for a good answer for this site (we prefer Q's and A's to be self-contained). – Kyle Kanos Apr 20 '15 at 02:44
  • (A) It's an actual link to an actual paper, by an actual astrophysicist.You can use google scholar to find it, it's easy enough. (B) The facts you will find in that paper. Which is more reliable than wikipedia entries just so you know. (C) just answering a question I spotted, next time I wont bother.

    (D) People who respond in lettered bullet points (except sarcastically) come across as a bit of a ****.

     –  Apr 25 '15 at 14:45
  • Uh, you know that there isn't even a link here, right? Note also that I am an actual astrophysicist too (click on my name to see my profile). Wikipedia is actually a pretty good resource for more basic jargon terms (such as synchrotron & cyclotron radiation), there isn't a need to cite Rybicki & Lightman (or what have you) for such things. – Kyle Kanos Apr 25 '15 at 15:05
  • My initial remarks were in an attempt for you to improve your answer, not to shoot you down in any way. Physics StackExchange wants to be the best source of information about physics, having high-quality answers is therefore desirous to this end. "Not-even-link-only" does not fall under the "high quality" category, so (again) my remarks were to get you to do more than just say, "Go read this paper to find your answer!" – Kyle Kanos Apr 25 '15 at 15:08