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I don't know that all of the information contained in this section is accurate. There are numerous theoretical reports that contradict the statement that "electrons whose kinetic energy is larger than the rest energy (511 keV) emit photons in forward direction while electrons with a small energy emit photons isotropically" (notably, L. Kissel, C. A. Quarles, and R. H. Pratt, At. Data Nucl. Data Tables 28, 381 (1983), on which the widely-used Monte Carlo code, PENELOPE, is based). Also, there are quite a few experimental reports that contradict the statement, as well (two examples off the top of my head: J. G. Chervenak and A. Liuzzi, Phys. Rev. A 12, 26 (1975) and D. Gonzales, B. Cavness, and S. Williams, Phys. Rev. A 84, 052726 (2011)). Maybe this section should be edited. 71.170.7.22 (talk) 21:28, 19 May 2013 (UTC)scott
Should the cross section per photon energy and angle by Köhn and Ebert be removed? I find it to be rather bulky, while equivalent equations exist in H. W. Koch, J. W. Motz, Bremsstrahlung Cross-Section Formulas and Related Data; Rev. Mod. Phys. 31, 920 and R. L. Gluckstern and M. H. Hull, Jr., Polarization Dependence of the Integrated Bremsstrahlung Cross Section; Phys. Rev. 90, 1030. The latter paper gives hints about how to solve the integrals from the Bethe-Heitler diferential cross section per frequency and photon and electron angles. Perhaps it is best to substitute Köhn and Ebert's equation for the simpler, older equation. — Preceding unsigned comment added by 83.165.101.201 (talk) 16:46, 25 September 2014 (UTC)
"-strahlung radiation" means "radiation radiation". I vote to put this article back to Bremsstrahlung where it belongs. Kosebamse 17:50 15 Jul 2003 (UTC)
Braking radiation has a graphical representation in the graph of X-ray intensity versus wavelength. This illustration can be found at http://fisica.indivia.net/frespettro.gif. I find it more descriptive than the verbal explanations....
http://fisica.indivia.net/frespettro.gif seems to be a dead link. Is there another place to see the illustration? —Preceding unsigned comment added by 170.134.55.135 (talk) 16:33, 2 January 2010 (UTC)
Art Carlson, Nikola Tesla was the first scientist to study X-rays produced by Bremsstrahlung. He may not be the most important (others would have more precisely research this). He didn't name this ... but he DID identify this process for obtaining x-rays (this is how he got some of his radiographs). -Anon
There was an inconsistency: The deffinition here coverd only breaking radiation, while the use in the article on gyrotrons was the more general one. David Ingham
The plasma section seems a little sparse. The formulas fall from the sky, with no references or non-numerical expression. I looked up the calculation in Ichimaru's book "basic principles of plasma physics: a statistical approach", p. 228. I get a formula (with hbar's, c',s etc.) I'll add in a few moments to the main article. Numerically it's within 10% of the quoted numerical result. I guess this partly depends on how you average over velocity distribution and so on. Also, Ichimaru's calculation involves a maximum wavenumber cutoff, which has a different value based on whether the classical distance of closest approach or the deBroglie wavelength is longer (same issue occurs when finding the Coulomb logarithm). The formulas in this section use the quantum (deBroglie) cutoff, which is correct for most hot, fully-ionized plasmas. Dstrozzi 19:23, 18 December 2005 (UTC)
One of the formulas on the page comes up with some sort of failed to parse error. Someone might want to work on that...
The figure seems to have an error. E1 is greater than E2, so it should be h(nu) (or hf) = E1-E2. —Preceding unsigned comment added by 198.129.216.160 (talk) 19:15, 9 July 2008 (UTC)
I added this section but couldn't think of a shorter name for the section. The name is a bit long.Rotiro
Evgeny, may I ask what is "BS" about Griffith's treatment of bremsstrahlung? I'm pretty sure the difference between Griffiths' and Diver's angular power distributions is that Diver's is valid in the rest frame of the moving particle, whereas Griffiths gives the radiation that an observer would see when watching a particle move with speed v subject to acceleration a. The latter is arguably more useful, and is certainly not "BS" !! I would suggest reverting the edit, except the relativistic generalization is useful. I think some combination of the two versions of this section would be best. Rotiro (talk) 20:01, 11 February 2008 (UTC) I wish I had my texts with me, but I don't. Consider consulting Landau & Lifshitz; that's a fairly authoritative source. Rotiro (talk) 20:10, 11 February 2008 (UTC)
Evgeny, I'm sure others will appreciate it if you use some critical thought and check well-established citations before replacing perfectly good content, and especially if you exercise some restraint before calling something "BS" (though perhaps you were referring to "BremSstrahlung" ? ;) ) Anyway, there were some weaknesses with the previously-existing content, which I have tried to fix, while also including some good points you put in. However, I think this should be kept fairly simple ... the intended audience is neither physics PhD's nor MSc's. Rotiro (talk) 13:26, 12 February 2008 (UTC)
In fact, the additional term due to a dot v in your expression gives a gamma^8 (!!!) dependance, which, along with the gamma^6 of the other term, only makes my point stronger. I have a strong preference for avoiding the complications of a discussion on proper vs. observer time, and not introducing additional notation, so do you mind if we change beta dot to (gamma a / c) ? And, do you have an expression for the relativistic angular power distribution for arbitrary a and v? I agree with you that there's not much point to consider only the case a||v. Rotiro (talk) 22:57, 15 February 2008 (UTC)
I added this section after being frustrated that every discussion on Bremsstrahlung radiation (BR) ignores its use in astrophysics, and specifically that BR has a broader application in the thermalized regime. The text is very simplistic, but is intended so to keep the reader from being bogged down in the specifics of calculations and physics details.
somebody recently shortened the article cutting away a lot of text and the plot. Why? It is true that the previous incarnation was somewhat chaotic, but there was some valuable information that disappeared Gringo.ch 17:19, 9 November 2006 (UTC)
This article really needs an explanation of what causes bremsstrahlung. There's a definition of the term, but that's it. Maury 13:09, 21 November 2006 (UTC)
"the photon's energy comes from the electron/neutron pair"
Should this read "...from the electron/proton pair"? --67.69.5.166 21:19, 23 January 2007 (UTC)
Shouldnt it be spelt Brehmsstrahlung? This spelling is supported by numerous website, and also the paper I am currently reading. —The preceding unsigned comment was added by RogueNinja (talk • contribs) 19:46, 2 February 2007 (UTC).
No, the spelling is correct (from german "bremsen", meaning to brake). 129.132.63.41 16:25, 1 March 2007 (UTC)
I came here to confirm I was spelling it correctly, as R. W. Bussard fairly consistently spelled it "bremmstrahlung", and I felt compelled to check after encountering that twice tonight. His spell-checker had no clue either way. The spelling in this article is consistent with every solid reference I've checked. Tomligon (talk) 03:08, 15 January 2009 (UTC)
defintely not "Brehmstrahlung", there's a german classic called "Brehms Thierleben", but that doesn't have anything to do with high energy fizzics =) ( cf. http://en.wikipedia.org/wiki/Alfred_Brehm, http://en.wikipedia.org/wiki/Brehms_Tierleben ) edit: wrong paste =)
I am from Germany, and it is Bremsstrahlung, without h and with one m. 137.226.140.178 (talk) 15:34, 26 November 2013 (UTC)
Somebody added a plural form "Bremsstrahlungen". I removed it, since I do not believe this is used in english. The OED (second edition) does not report it. —The preceding unsigned comment was added by Gringo.ch (talk • contribs) 14:16, 2 April 2007 (UTC).
: second that, "Bremsstrahlungen" doesn't make any sense, at least to a native speaker =) —Preceding unsigned comment added by 87.79.148.234 (talk) 22:53, 24 November 2009 (UTC)
I've always wondered : Bremsstrahlung can occur when a particle enters a medium for which the speed of light is less that its actual speed. What happens when the speed of the particle has reduced to be equal to the speed of light - in terms of the dilation factor being infinite?
Also, is there any conceptual link between BS (no pun intended) and tachyons? OrangUtanUK 17:30, 16 August 2007 (UTC)
You may find the page on Cerenkov radiation helpful; this refers to light emitted when a charged particle moves faster than the speed of light inside a medium. When you refer to the "dilation factor", perhaps you mean the Lorentz factor ("gamma") that appears in special relativity? The speed of light "c" in the Lorentz factor is always the speed of light *in vacuum*, so nothing "mysterious" happens from the special-relativistic viewpoint when a particle moves at the speed of light *in a medium.*
I don't think there's any link between brems. and tachyons (with BS, perhaps), but I am not a high-energy physicist.
Your comments triggered my BS detector regarding various misconceptions surrounding "the speed of light." In case you or others are not clear, as far as physics is currently known, there is no way to send information faster than c (speed of light in vacuum). Inside a medium, wave phenomena (such as light) have several "speeds", in particular a phase velocity and group velocity. Typically, information and energy travel at the group vel, which is always <= c, although the phase velocity can exceed c (this is the usual case in plasma physics). Dstrozzi 18:01, 18 August 2007 (UTC)
Could someone put in a section on contrasts with other raditions? Just wondering. J. D. Redding 21:40, 11 March 2008 (UTC)
Is this the same phenomena? http://www.sciam.com/article.cfm?id=x-ray-machine-adhesive-tape --82.181.201.182 (talk) 18:17, 28 October 2008 (UTC)
The Continuous x-ray (edit | talk | history | protect | delete | links | watch | logs | views) article looks like it duplicates material from bremsstrahlung, along with a bit of material from either photon or electron volt. It doesn't seem to introduce any new information, and doesn't seem to be a detailed enough treatment to justify a separate article, so I've proposed the merge. Please comment as to whether or not a merge should occur. --Christopher Thomas (talk) 21:19, 8 October 2009 (UTC)
Done. I actually added a whole section, "Output of X-ray tube", explaining the concept, then turned continuous x-ray into a redirect. :-) --Steve (talk) 19:08, 20 February 2010 (UTC)
The article says
but I'm sure the power spectrum is finite and constant at low frequencies (which is the origin of the infrared divergence). It's only the number of photons that diverges, not their power. --Michael C. Price talk 05:41, 20 February 2010 (UTC)
Should bremsstrahlung be capitalized or not? It looks like there is an arbitrary mix of capitalizing it and not on the page already... so is there some consistent and correct approach? —Preceding unsigned comment added by 98.155.93.196 (talk) 06:27, 11 May 2011 (UTC)
I just noticed that the use of italics is similarly inconsistent. Art Carlson (talk) 07:47, 11 May 2011 (UTC)
'free-free absorption' appropriately redirects to this page, but it isn't mentioned once in the article. While emission is the more common and important thing to discuss, absorption definitely needs to be addressed as-well --- i think it warrants its own section. All Clues Key (talk) 18:48, 28 July 2012 (UTC)
Please read Talk:Larmor_formula#Inconsistent_with_Bremsstrahlung?? and discuss there. Thanks!! --Steve (talk) 14:21, 12 December 2012 (UTC)
"The absolute value of the virtual photon between the nucleus and electron is..."
Absolute value is a mathematical concept.
Something like a virtual photon cannot have an "absolute value".
A real number, a complex number, a vector, etc., does have an absolute value.47.215.180.7 (talk) 18:35, 27 February 2018 (UTC)
Perhaps add some mention of transmission-bremsstrahlung effect, where x-ray photons have generally the same trajectory as the relativistic electrons producing the x-rays? (Or should this be a separate WP article entirely?) For relativistic e-beams, the emission angle is not the 180deg seen with conventional x-ray tubes. Some higher-resolution (microfocus) x-ray tubes employ so-called "tantalum converter" membranes (or membranes of W or Pt;) naturally producing an x-ray output in a narrow beam; the same phenomenon being well known in accelerator experiments (search "Tantalum Converter," bremsstrahlung converts gast electrons into a narrow beam of x-rays. This is not the commonly-explained "reflection bremsstrahlung.") When I first became curious about this topic, online search turned up zilch. A few years later I stumbled across the proper search terms: "Cone-beam" x-ray tubes based on "Transmission" bremsstrahlung, also "Tantalum Converters" using bremsstrahlung to "convert" MeV electron beams into MeV x-ray beams. Recent example, Sandia's Hermes-III (a military bomb-effects simulator) sends an e-beam against a meter-wide tungsten sheet, and a meter-wide, kilometer-long x-ray beam exits from the other side of the sheet. 128.95.172.170 (talk) 22:50, 6 January 2021 (UTC)
absorptivity is defined but its value is not given. Also $I_nu$ is defined in the section "Thermal bremsstrahlung: emission and absorption" But insead a new variable B_Br is defined in the next section. Can someone complete this by giving the formulae for these? — Preceding unsigned comment added by 2600:4040:233A:BE00:9925:8EEE:A87D:366 (talk) 19:38, 12 July 2022 (UTC)