Talk:Gamma-ray burst

Changes

Hm, I see a lot of changes have been made in the past month or so. While splitting up the article is probably a positive development some of the recently edited or added text is rather incoherent or poorly worded... I'll try to do some cleanup in the next couple weeks. I made some small changes tonight but did not do a very thorough job with referencing; something I'll try to work on soon if somebody else doesn't beat me to it. Daniel Perley (talk) 10:46, 21 November 2007 (UTC)

Credibility of History Channel as source

I noticed that the vast majority of cited sources in this article are highly credible, academic sources, with one major exception: Source #32, "History Channel, Mega Disasters, Gamma Ray Burst". I've seen some of the History Channel "documentaries" before; they're highly un-academic and seem to focus garnering viewers through sensationalism (particularly through exaggerating the possibility of some big apocalyptic disaster, then leaving viewers hanging for more details after a commercial break, which then turns out to be anti-climatic) more than being factually accurate or presenting all relevant information. Even Wikipedia's own article on it has plenty of dirt that I would consider enough to discredit it as a source, especially for a statement that says something could "incinerate the Earth". I'll remove the statement and citation from the article for now, but I'd like to hear if anybody has any arguments for keeping it in. --Poochy (talk) 06:27, 24 March 2008 (UTC)

What needs to be seen is if history channel attributed the statement to someone well known in this field, then maybe we can add the cite and state that "History channel showed a documentary in which Mr XYZ said so and so...."....but if the point was made by channel itself and not by some specialist, then i guess deleting it might be justified. Maybe someone who saw the episode might be of some help here ... Gprince007 (talk) 07:41, 24 March 2008 (UTC)

Mass extinction on Earth - 10% survival rate citation

this is said by one of the sientist who also worked on the "Did a gamma-ray burst initiate the late Ordovician mass extinction?" report, on the episode "Human Extinction" of the "Earth Investigated" on the National "Geographic Channel"

posting this here to be sure that this information doesn't get lost (and it's not enough for reference)

My comments

Alrighty, Jehochman! First off, I must admit that while I do work on mostly science articles, I know very little about astronomical physics. However, I firmly believe in the value of fresh eyes. So here's my plan of attack: First, I'll go through the article and find weaknesses in the prose. If I notice any major gaps in the content, I'll list them here too. Second, I'll go through the references to check for reliability and such. After that, I'll compare the current article to the revision as of the end of the previous FAC and see which of the objections have been adequately dealt with and which have not. As for completeness and content, consider contacting the members of WP:SPACE or WP:AST if you haven't already. All that being said, let's get started! --Cryptic C62 · Talk 22:54, 29 November 2008 (UTC)

Thank you for these ideas. I will work on it the next chance I get. Jehochman ^Talk 01:30, 2 December 2008 (UTC)

General

• The article mixes "gamma ray" with "gamma-ray". Which is correct? Even if both are correct, the article should be consistent.  Done
  • The literature appears to be unanimous in using the hyphenated version. I've moved the article and related articles, but we will need to clean up Category:Gamma ray bursts. Perhaps somebody has an automated tool that can help. Jehochman ^Talk 16:29, 19 December 2008 (UTC)

I just got permission to use AWB. I'll try it out in the next few days. Done

The standard rule (eg, ApJ, Nature ...) has been that "gamma-ray" should be hyphenated when used as an adjective, as in "gamma-ray telescope" or "gamma-ray burst", but not when used as a noun, as "Gamma rays are the shortest-wavelength form of ...." Seems fussy (and often broken) but I believe it still applies. (The same rule applied to "x ray", BTW.) Wwheaton (talk) 18:20, 10 January 2009 (UTC)

• Here's something that confuses me. Why is it that the first GRB detected was assigned the number 670702? It seems to me that the first should be labelled 000001! I'm joking, of course, but I think that if you can find information about how GRB numbers are designated, it would make a good addition to the article.

  Hrm, I just noticed Note 12. This is an odd place for the explanation. Any way you can squeeze it into the main article somewhere?

Lead

Resolved comments

• "...but the number of GRBs that could be observed from Earth is about three times this and is currently limited by the efficiency of the instruments." Not sure what this means. Are you saying we should be able to see more GRBs based on theoretical data, and that the only reason we don't is because of bad equipment?  Done
• "...a different process, the leading candidate being the collision..." I was unaware that GRBs participate in elections! Perhaps you meant something like "the leading theory being" or "a commonly accepted theory being".  Done
• "All known GRBs originate from outside our own galaxy" + "The sources of most GRBs are billions of light years away." These two statements imply characteristics that are true for all GRBs, past present & future, which I'm assuming isn't exactly true. Consider replacing the instances of present tense with the present perfect (have originated, have been).  Done
  • I have fixed the above items. Please check. Jehochman ^Talk 15:05, 3 December 2008 (UTC)  Done

    Looks good. I agree with your choice to delete the bit about the inaccurate equipment. To explain it clearly would require going into much more detail than the lead really needs. --Cryptic C62 · Talk 17:49, 3 December 2008 (UTC)

Discovery and History

• "Cosmic gamma-ray bursts" This is the first and only use of "cosmic," yet there is no explanation of the word given. Eh?  Done
• "...details of the Vela Incident..." It's not clear why this particular incident is singled out. Is this the only notable incident involving the Vela satellites? If so, this should be stated explicitly. Perhaps it should also be moved into its own sentence, as it reads awkwardly enough as it is now. Done
• "looked nothing like a nuclear weapons signature" Do you mean a nuclear weapon's signature or nuclear weapon signatures?  Done
  • Rereading this sentence, the word "looked" doesn't seem quite right. It's neither encyclopedic nor scientific. Also, using "looked" implies that the analysis of these radiation flashes was based entirely upon a simple visual comparison, which I have a hard time believing. If it really is about visible differences, consider rewording to include the word "appearance". It it isn't just about visible differences, find a more specific word.
• "These results were published in 1973" Results of what? Perhaps "findings".  Done
• "prompting the scientific study of GRBs" Huh? The paragraph jumps straight from discovery of the events to studying them without even explaining how they were identified and named. At the very least, this should be rewritten to "the scientific study of what were then identified as GRBs". Done Also, by whom were these studies conducted? What new information did they find?  Done
• "such as Apollo and the Soviet Venera probes" Somewhat US-centric. Why does it clarify that Venera probes were Soviet, but not that Apollo was a US program?  Done
• "However, some believe there is a third type of GRBs.$\sum _{n=5}^{9}[n]$" Wow. Lots of citations. If it's that amazing, why is there no elaboration or explanation of this third type whatsoever?  Done
• "as predicted by most models" If scientists had no idea where the GRBs were coming from, how could they model them? Perhaps you need to clarify what sort of model you're talking about.  Done Unclear what the statement meant, so I have removed it. Jehochman ^Talk 21:25, 5 December 2008 (UTC)
• "the first of many to come" I can't seem to find the relevant policy page at the moment, but it goes something like this: Don't hint at information that will appear later in the article. If it's relevant now, state it plainly. If it isn't, leave it out.  Done
• "which combines a sensitive gamma-ray detector with the ability to slew on-board X-ray and optical telescopes" I'm not a scientist, so I could easily be wrong here, but "slew" doesn't sound like a very scientific verb, and even if it is, it might not immediately make sense to the average user. Perhaps "aim" or "point" ?  Done
• "The mission has also discovered huge X-ray flares" "Huge" doesn't carry with it a particularly encyclopedic tone. How about "large" ?  Done
• "On June 11, 2008 NASA's Gamma-ray Large Area Space Telescope (GLAST), later renamed the Fermi Gamma-ray Space Telescope, was launched." Several problems here: First, it's a one-sentence paragraph. Second, it has no citation. Third, it is unclear how this statement is relevant. What's special about GLAST?  Done

Galactic vs. extragalactic models

Resolved comments

• "the distance scale to GRBs was completely unknown" Does this mean from Earth to the GRBs, or from our galaxy to the GRBs?  Done
• "only two theories were considered generally viable" considered generally viable? or generally considered viable? also, by whom are these theories being considered?  Done
• " that GRBs originate from a very large, diffuse halo (or "corona") around our own galaxy" The phrase "around our galaxy" implies that the GRBs do not originate from within our galaxy, but instead, nearby. However, the title of the section is Galactic vs. Extragalactic. Perhaps replacing "around" with "in or nearby" would clear up the ambiguity.  Done
• "Supporters of the galactic model pointed to the class" The verb "pointed to" doesn't carry with it a very encyclopedic tone. Perhaps "suggested"?  Done
  • I have checked all the above and done a copy edit to reduce ambiguity and improve tone. Please check. Jehochman2 (talk) 16:05, 7 December 2008 (UTC)

    Your corrections all seem fine to me. When discussing the three possible origins of a GRB, is "merger" the correct word for that sentence? It doesn't sound very scientific, but I've been wrong about these kinds of things before.--Cryptic C62 · Talk 21:02, 7 December 2008 (UTC)

• "and that an extragalactic model was far more natural regardless of its problems" Doesn't flow particularly well, and "natural" isn't the best word choice. How about "and that an extragalactic model, despite its various flaws, would more closely fit the available data." or something like that?
• "while the most distant known (GRB 080913) has a redshift of 6.7" has or had?
• "GRB 080913's "lookback time"" either link "lookback time" to an appropriate article, or give a short explanation here.

  Items immediately above are  Done. Jehochman ^Talk 22:43, 7 December 2008 (UTC)

GRB Jets collimated emission

• "Many GRBs have been observed to undergo a jet break in their light curve" What is a jet break? It's unclear if the second clause defines the term or is just elaborating.  Done
• "the optical afterglow quickly changes from slowly fading to rapidly fading as the jet slows down" Way too many speed-related adverbs in this sentence. Also, what's a jet?  Done
• As I continue to read this paragraph, it becomes more and more confusing as it continues to use phrases including "jet". There is obviously a large disconnect between the article and your understanding of jets. What they are and how the word is used needs to be clearly stated near the beginning of the section.  Done
• "the true energy release of a (long) GRB is approximately constant—about 1044 J" Why is long in parentheses? Also, does this sentence mean that all long GRBs have the same energy release? Or that for the duration of any single GRB, the rate of energy release is constant?  Done
• "1044 J, or around 1/2000 of a solar mass" there appear to be conflicting units here. Why would a solar mass be measured in joules? Do you mean "1/2000 of the energy released by a solar mass"?  Done
• "Bright hypernovae do in fact appear to accompany some GRBs" This implies some deeper connection between hypernovae and GRBs, but then the paragraph ends. Eh?  Done
  • "suggesting that hypernovae may be a source" Source of what?
• "only a small fraction happen to be pointed the right way to allow detection" The use of "allow" implies some form of control. How 'bout "...pointed such that they can be detected." or something along those lines?  Done
• Short GRBs probably shouldn't be its own subsection. It's very short, and it refers to "the above arguments".  Done
• "They appear to be generally less beamed or possibly not beamed" I think "not beamed" needs to be emphasized further. How about "or possibly not beamed at all"?  Done

Progenitors

Resolved comments

• The title of this section is more fit for a children's book than an encyclopedia. I'd just shorten it to "Progenitors" and include a brief definition of the word somewhere early on in the section. Example: "...has made investigation of the progenitors, the systems that produce these explosions, ..."  Done
• "The currently favored model" Unnatural wording. How about "Currently, the most widely-accepted model..." or something like that?  Done
• "in which the core of an extremely massive, low-metallicity, rapidly-rotating star collapses into a black hole" Issue that needs to be clarified here: Is a collapsar an event that is already known to occur which scientists believe cause GRBs? Or is a collapsar a purely theoretical model whose only purpose is to explain the existence of the GRBs? In other words, which came first in the history of science?  Done
• "While the collapsar model has enjoyed a great deal of success" This phrasing seems better suited to describing a musician, not a theoretical model. What does "a great deal of success" even mean? Lots of people support it? It sufficiently explains many of the observed data? It has been written about more than any other model? It was a model on Project Runway?  Done
• "Winds from highly magnetized, newly-formed neutron stars (protomagnetars)" It seems like there's something missing here. How does a newly formed star create wind? Perhaps a wikilink to a relevant article would help.  Done

Emission mechanisms

Resolved comments

• "(X-ray through radio)" those readers not entirely familiar with wavelengths will probably be confused by this parenthetical comment. Wikilinking will help, as will expanding it to something like "ranging from X-ray through radio".  Done
• The title of the section is plural, and the first sentence points out that there is no single accepted theory. So why is it that this section only discusses one theory (the synchrotron emission)?  Done
• "Inverse Compton scattering may cause gamma ray emissions observed after a GRB" Doesn't quite read correctly. Either adding "the" before "gamma ray" or changing "a GRB" to "GRBs" would make it flow better. Done
• "If a GRB progenitor ... explodes within a stellar cluster, the resulting shock wave may generate gamma rays" Consider changing to the subjunctive mood: "If a GRB progenitor ... were to explode within a stellar cluster, the resulting shock wave could generate gamma rays" Done
• " As the relativistic matter ejected from an explosion slowed and interacted with ultraviolet wavelength photons, some photons would gain energy, generating gamma-rays" You've slipped back into the past tense here. Also, should there be a hyphen between "ultraviolet" and "wavelength"?  Done
• The second paragraph of this section is too short. Consider expanding upon the different models, adding more theories, or rearranging the section to more evenly divide the content.  Done expanded. These two theories seem to be the only ones worth mentioning.

Mass extinctions

• "The idea that a nearby gamma-ray burst could significantly affect the Earth's atmosphere and potentially cause severe damage to the biosphere was introduced in 1995 by physicist Stephen Thorsett, then at Princeton University." This reads a bit too much like a Dan Brown novel. Consider rearranging the sentence so Thorsett and 1995 are introduced at the beginning.  Done
• "Gamma-ray bursts within the Milky Way galaxy every 100,000 - 1,000,000 years." This is what English professors like to refer to as "not a sentence".  Done I thought I had typed a verb. :-)
• Why the sudden jump from 1995 to 2005? Did nothing happen with this theory in 10 years? At the very least, Thorsett's theory should be elaborated upon before moving on to the NASA/University of Kansas study.  Done Apparently not much happened on this speculative/sensationalistic theory.
• "rather the strength of their work was their atmospheric modeling, essentially a "what if" scenario." Huh? I really have no idea what the last clause is referring to.  Done
• "ultraviolet radiation from the Sun would kill much of the life on land and near the surface of oceans and lakes, disrupting the food chain" Having the food chain bit at the end makes it seem like the most important consequence. Perhaps you should go on to elaborate as to why disruption of the food chain is such a big deal.  Done
• "metal-deficient galaxies are the most likely candidates." Again, they are not participating in an election.
• "The likelihood of the metal-rich Milky Way galaxy hosting a GRB was estimated at less than 0.15%, significantly reducing the likelihood that a burst had caused mass extinction events on Earth"  Done Gone back to the original paper and deciphered what they were saying.
  • The statistic presented is meaningless without context. Does it mean that there is a .15% chance that it ever hosted a GRB? Some kind of time frame needs to be added.  Done
  • An estimate doesn't change the likelihood of something else happening. Perhaps you meant to say that the estimate suggested a significantly lower likelihood or some such.  Done
• "at least one nearby event has probably hit the Earth in the past billion years, with life on Earth being at least 3.5 billion years old" While it may be obvious to us what the second clause is implying, not everyone will understand. It should be explicitly stated that if a GRB occurred in the Milky Way while life was present on earth, it could have caused an extinction event.  Done
• "has been found to have a rotational axis aligned within 16° of the solar system. The chances of it producing a gamma-ray burst are small, ..." So what? This paragraph needs to be expanded, and it should be made clear why the rotational axis alignment is relevant here.  Done
• "Comparative work in 2006" By whom? A quick glance at the citation at the end of the paragraph doesn't even state who was conducting this work. It's especially important to be clear about this here because the other paragraphs all mention specific persons and organizations.  Done
• "it is most unlikely that a nearby GRB has caused mass extinction events on Earth" This conclusion should not be presented as fact; the very next paragraph reaches the opposite conclusion. It should be made clearer that neither of the two conclusions are known to be true or false.  Done

Notable GRBs

• Knowing that you plan to bring this article to FAC again, I think a bulleted list is the wrong way of organizing this section. I recommend picking a few GRBs that are highly notable and are not already mentioned in the article and expanding those into full paragraphs. Consider the following question: If the GRBs are notable enough to appear in the article, shouldn't they be notable enough to be in a full paragraph?  Done
• To avoid making this section too long, consider adding GRBs with their own articles to the See Also section. Category:Gamma ray bursts would also be a helpful link, either as a hatnote or part of the See Also section.  Done
• "This was the first with a successfully detected afterglow." Unclear meaning. Was "this" the first satellite to successfully detect an afterglow? Or was "this" the first detected GRB to also have its afterglow detected?
• "GRB 970508 was the first with a measured redshift. The extent to which the radiation is redshifted allows astronomers to calculate an estimate of the distance of the event), 0.835." Uh...  Done
• "momentarily reaching or exceeding a magnitude of 8.9"
  • Is this the magnitude of GRB 990123, or of GRB 080319B?
  • 8.9 what? Pirates?
• "despite its distance of nearly 10 billion light years" Distance requires two points. I'm assuming this means 10 billions light years from earth?  Done
• "GRB 030329A was an extremely close (z=0.168), and therefore extremely bright GRB" - References did not look good for this one, so removed it.  Done
  • What is (z=0.168)? This bit of terminology definitely needs to be clarified.
  • Here you imply that a close GRB will also be a bright GRB, but in the previous paragraph, you mentioned that the brightest GRB ever was 10 billion light years away. Hmm...
• "GRB 030329 was so bright..." The sentence before this was about GRB 030329A. Different incidents, or typo? Removed  Done

References

Most of my comments here are pretty trivial, so I'll probably correct them later if you don't. I'll list them here either way so you know what I'm doing.

• Consider separating the explanatory notes and references into two separate sections. This might solve the problem of where to put the information about the GRB naming conventions. See Wikipedia:Footnotes#Separating_reference_lists_and_explanatory_notes.
• I think that when you provide a DOI, you're not supposed to link the name of the article. I'll check with Ealdgyth.

  According to SandyGeorgia, if the DOI and the URL both link to the same page, the URL is unnecessary. If, however, the DOI goes to an abstract while the URL leads to the full article, then both are to be included. I'll go through the journal refs and makes changes where necessary.

• Note 3 (A Gamma-Ray Burst Bibliography) has the author listed First initial. Last name whereas the rest of the citations use Last name, First initial.
• Note 4 (Spatial distribution of gamma-ray bursts...) has no space between the author's two initials, while the rest of the citations use a space.
• Note 17, 24, 47, 50 use The Astrophysical Journal while the rest use Astrophysical Journal. Are these the same publication?
• Note 24 (Jet Breaks in Short Gamma-Ray Bursts) lists all of the authors while the other citations with more than 3 authors use et al.
• Note 27 and 28 are missing first initials for the main author.
• Note 31 and 33 use ApJ as the publication, whereas the rest spell out the full title, which I presume to be Astrophysical Journal.
• Note 37 (Gamma-ray bursts from synchrotron self-Compton emission) is missing information that's readily available on the article's page.
• Note 39 (Optical and Long-Wavelength Afterglow from Gamma-Ray Bursts) has a random tilde (~) in it?
• Note 46 (badastronomy.com) is incomplete.

I fixed most of these, but am unsure about 37 and the correct publisher for 46. Jehochman ^Talk 03:23, 7 January 2009 (UTC) ...

Third paragraph in lead

I find part of the following sentence a bit confusing:

“ Though the short duration of a gamma ray burst would limit the immediate damage to life, a nearby burst might alter atmospheric chemistry by reducing the ozone layer and generating acidic nitrogen oxides. ”

The fragment Though the short duration of a gamma ray burst would limit the immediate damage to life is vague. GRB will cause mass extinction in Earth, whether short lived or long lived. This is why I think this part is unnecessary. What is meant by "limit the immediate damage to life"? How are you calculating the damage with the duration of the GRB? What is the standard time a GRB will need to cause mass extinction? Otolemur crassicaudatus (talk) 17:21, 10 December 2008 (UTC)

Another important point, the fact that mass extinction on Earth due to GRB is highly unlikely should be mentioned in the lead to give a clear picture. Otolemur crassicaudatus (talk) 17:50, 10 December 2008 (UTC)

It seems like you and I have made the necessary changes. Are you satisfied with the current lead? Jehochman ^Talk 14:03, 19 December 2008 (UTC)

To be done before FAC

We need to expand the Types of bursts and Research missions sections, based on comments at the last FAC over a year ago. In particular, there are a few significant missions that have not been mentioned (RXTE and HETE), and we probably need to identify the InterPlanetary Network and the Gamma-ray Burst Coordinates Network. Jehochman ^Talk 15:48, 10 January 2009 (UTC)

Okey doke. I can try to assist with the research if you want, but I don't know how much help I'll be. Leave a message either here or on my talk page when you're done expanding those sections, and I'll start reviewing them, yeh? --Cryptic C62 · Talk 17:23, 10 January 2009 (UTC)

Vela gamma-ray detectors looked for nuclear tests in space

I have reverted an edit today, by El Wray (talk), that claimed that the Vela satellites were intended to detect gamma-rays from nuclear tests on the Earth, not in space. This is incorrect. The 1963 Nuclear Test Ban Treaty barred tests in the atmosphere or in space. There was a concern that tests in space would not be noticed by earth-based monitoring. The optical flash of such tests might be bright, but would be very brief, and not necessarily obvious if exploded far from Earth, on the day side of the Earth, or behind the Moon. A test in the atmosphere, if conducted at low altitude (say below 10 km), would not produce a gamma-ray flash observable from space, due to absorption in the overlying air. (There could be a much slower, minutes to hours, rise seen in space detectors due to delayed emission from radioactive materials lofted by the cloud of debris.) The very short, very intense flash of gamma rays from a space nuclear test would be easily observable and distinct from the natural sources known before the Vela spacecraft were launched. By spacing them around the Earth at distances of about 100,000 km, approximate positions (and hence also device yields) could be determined from the relative timing of the burst observations. Even a test behind the Moon would produce an expanding sphere of very fast-moving, intensely radioactive fission products, that would spread beyond the rim of the Moon within about a second. If I recall the Vela spacecraft did have detectors that might have detected the optical flash from a surface test, or possibly other signatures. A good reference for the design and capabilities of the Vela spacecraft would probably be in the proceedings of the October 1973 Los Alamos conference on gamma-ray bursts, of which I believe I still have a copy, though not conveniently at hand. Wwheaton (talk) 04:22, 29 January 2009 (UTC)

Our own Wiki Vela article gives further details about the spacecraft and their capabilites, and confirms my statements above. The capability of observing on-Earth tests was added in the second series of "Advanced Vela" satellites, and resulted in the detection of the characteristic optical flash of a nuclear explosion in the atmosphere, on 22 September 1979, by the Vela 6911 spacecraft, somewhere over the southern circumpolar ocean, near South Africa. I believe this "Vela Incident" is now widely believed to have been a nuclear test, possibly due to a collaboration between South Africa and Israel. Wwheaton (talk) 05:00, 29 January 2009 (UTC)

Reorganization?

As I continue to expand upon the Research Missions section, it is becoming increasingly apparent that the organization of this article is flawed. As it stands now, most pieces of information could logically fit into two distinct locations in the article. Discovery and Research Missions provide a general overview in chronological order, while the rest of the article focus primarily on our current understanding of GRBs, but instead broken up by subtopic. Any suggestions on how to reorganize the information to reduce the opportunity for redundancy and improve the flow? --Cryptic C62 · Talk 21:41, 20 February 2009 (UTC)

Actually i've had this article on my watchlist for a long while now....i had copyedited this article a long time back and since then it has changed a lot....infact in past few months, there have been too many additions and i had stopped keeping track of it....however, i feel that the article may need some restructuring and i'll be glad to help with copyediting once the article becomes STABLE. Once the structure of the article is agreed upon by editors and article is STABLE, I'll be glad to offer my services in copyediting the article !!! Gprince007 (talk) 14:53, 22 February 2009 (UTC)

GROND credit

I have created a stub for GROND. I'm bringing this up because of the confusion I've seen in the popular media and web forums about the importance of the GROND team's work in the observation of GRBs, and the significance of the discoveries (ie, modeling of GRB emission mechanics; interpretation of redshift, distance scale and energetics).

For example, both GRB 080913 and GRB 080916C (the most-distant and most-powerful GRBs observed to date, respectively) were observed and back-extrapolated by the GROND team (NASA pr 1, NASA pr 2). Though Fermi and Swift detect GRBs and alert the network (and that is amazing in itself), in both of these cases the work of Jochen Greiner's team was essential in determining distance and energy.

I'm planning on working this into Gamma-Ray_Burst#Distance_scale_and_energetics (minimally... I've seen the history of splitting this article into smaller pieces) unless there are any objections. Also, this is a heads up that there is now an article to link to when there are other news-worthy stories regarding GRBs (and there will almost certainly be more). demonburrito (talk) 23:04, 23 February 2009 (UTC)

Notable GRBs organization

Hey all. I've updated and cleaned this section a bit.

For the organization of this section in its current form, I've made a draft here with subsections for each event. I saw the earlier objections to making it a list; but I thought that subsections might work well, for the following reasons:

1. Some paragraphs are too long, while providing the bare minimum of info to show the notability.
2. In the future, each event could have a main article link (all but one of them have articles).
3. In the distant future, event descriptions could be a transcluded from a stand-alone list article.

Even if none of the above apply, it still looks pretty and is more navigable. I suspect lots of people hit this article first when looking for background on news reported in the popular science press. demonburrito (talk) 14:26, 28 February 2009 (UTC)

Major retooling

For those who haven't noticed, this week (2009 May 5-12) I'm trying to do a another major retool of the site to bring it fully up to date and improve the organization/emphasis a little. Feel free to point out or correct any problems that come up with rewritten sections or if there is resistance to removing particular content. (Grammar cleanup and typo patrol also appreciated.) Daniel Perley (talk) 09:24, 8 May 2009 (UTC)

You may be interested in using {{In use}} or {{Under construction}}. --Cryptic C62 · Talk 11:10, 9 May 2009 (UTC)

Good to know! By the way, I see someone has been uncapitalizing the uses of "Galactic". This is not a typo; Galactic in this sense means referring to the Milky Way Galaxy. Anyway, after some exhaustive editing I'm now essentially done. Daniel Perley (talk) 10:55, 12 May 2009 (UTC)

Some redlinks

1. Afterglow (gamma-ray burst)
2. Ray Klebesadel
3. GRB 980425
4. WR 124
5. GRB 790305b
6. Acta Astronomica

Could make for some interesting DYKs... Cirt (talk) 20:24, 15 May 2009 (UTC)

Aye, I definitely plan on DYKing an Afterglow article at some point if no one else gets to it. I'll probably have to wait until January 2010 before I have access to good sources, though. --Cryptic C62 · Talk 20:26, 15 May 2009 (UTC)

Added one more, Acta Astronomica. Cirt (talk) 06:31, 16 May 2009 (UTC)

I noticed an afterglow stub article was made for a while, but now it just redirects right back to gamma-ray burst... what's up with that? Daniel Perley (talk) 11:16, 23 May 2009 (UTC)

PBH Evaporation

Adding this is fine, though the classification section should probably (in my opinion) stick to models that have been confirmed to apply in at least come cases or are otherwise broadly accepted by the community. Primordial black hole evaporation is still entirely theoretical; PBH's are not known to exist in nature and no GRB has been convincingly shown to have the characteristics of an evaporation explosion. It's definitely worth mentioning in the Progenitors section, though so I'll leave that one and move the wikilinks there. —Preceding unsigned comment added by Daniel Perley (talk • contribs) 23:16, 17 May 2009 (UTC)

That's fine. I was not sure where to mention it. Jehochman ^Talk 00:15, 18 May 2009 (UTC)

"since the Big Bang"?

"They are the most luminous electromagnetic events in the universe since the Big Bang." Reference? What exactly is meant by the luminosity of the Big Bang? --98.176.24.91 (talk) 21:09, 3 June 2009 (UTC)

The mentioning of the Big Bang in this sentense only causes confusion. I propose to change "They are the most luminous electromagnetic events in the universe since the Big Bang." to "They are the most luminous electromagnetic events occurring in the universe". --65.105.195.14 (talk) 00:25, 16 June 2009 (UTC)

Dear RobertG, "previous edit lost the idea that the big bang was more luminous" - yes, that was the exact intent of the edit. I couldn't find any source that would give a definition of the luminosity of the Big Bang. Could you cite one? And regarding your question "where else" can events occur if not in the universe. I think it's inaccurate to say that the Big Bang was an "event that occurred in the universe". So I thought that adding "in the universe" to the sentense would make it more accurate and less confusing. --65.105.195.14 (talk) 20:11, 24 June 2009 (UTC)

Dear Jehochman, "This is what the sources say; not for us to decide truth; we just report". Right. So could you please reference a verifiable source of the statement in question? Thank you. --65.105.195.14 (talk) 21:04, 24 June 2009 (UTC)

Dear All, let me clarify my concerns. I am trying to understand the meaning of the phrase "They are the most luminous electromagnetic events in the universe since the Big Bang". I have some basic training in physics and math. I am not a native English speaker, but I rarely have problems with reading comprehention. So please help me interprete the phrase correctly. If "since the Big Bang" is interpreted as "after the Big Bang" it makes the phrase meaningless but harmless: no new information means no wrong information. However if we interprete "since the Big Bang" as "apart from the Big Bang" then we either need to explain what exactly is the luminosity of the BB or to reference a verifiable source. So, what does "since" mean in this context? Thank you much for your attention and time. --65.105.195.14 (talk) 23:49, 24 June 2009 (UTC)

I believe that the sentence was intended to convey the second meaning that you proposed: "apart from the Big Bang". I do not remember this being explicitly stated in any of the sources. I believe the sentence that you proposed is a fair compromise for now, and I will revert back to it. Jehochman may not have been the one who originally wrote that sentence; we recently asked an expert contribute to the article: User:Daniel Perley. He is probably not active anymore. You may wish to contact him, though I can do it myself if you'd like. --Cryptic C62 · Talk 03:16, 25 June 2009 (UTC)

Thank you Cryptic C62. I have seen mentionings of the big bang luminosity and even of its spectrum in special articles on cosmology, but have never found any definition of those terms. Which photons do we count? Over what time period? I agree that we should better refrain from mentioning it until experts tell us what it really is. --98.176.24.91 (talk) 04:28, 25 June 2009 (UTC)

Let me explain my edit. This edit changed the page to say that gamma-ray bursts are "the most luminous electromagnetic events occurring in the universe", and I removed "occurring in the universe" as entirely superfluous. I then read it again, and it now said "[gamma-ray bursts] are the most luminous electromagnetic events" which was not what the earlier version of the article said. However, I partially agreed with the original edit, because calling them the "most luminous electromagnetic events since the Big Bang" might imply that more-luminous events were known before the Big Bang, which we cannot observe. So I partially restored what was there before as "apart from the Big Bang". I do not know whether the Big Bang was more luminous than gamma-ray bursts, but the article recently passed WP:FAC with that sentence in place. --RobertG ♬ talk 08:23, 25 June 2009 (UTC)

Thank you RobertG. Maybe "the most luminous electromagnetic events observed" would be a better formulation?. Such claim would be readiliy verifiable by the sources. --98.176.24.91 (talk) 12:43, 25 June 2009 (UTC)

How about "the most luminous electromagnetic events occurring in the known universe"? The addition of "known" may make it clearer that there exists the possibility of more luminous events that have not yet been discovered. --Cryptic C62 · Talk 14:55, 25 June 2009 (UTC)

"The known universe" sounds kind of sci-fi to me. But I better leave the choice of wording up to native speakers.--65.105.195.14 (talk) 16:06, 25 June 2009 (UTC)

causes of GRB's

Shouldn't it have something about the possible causes of the explosions relating to these extremely rare events? I read somewhere that they can happen when: Either two neutron stars rapidly spiral together, eventually to collide and anhialate eachother. Or, even rarer, an abnormally large star explodes into a hypernova... It was on a poster from an acclaimed sciency magazine, but i forgte the name. Must be the heat. If these causes are already stated, that is fine, because i have only read the bits which possibly relate to this. Stakingsin (talk) 17:34, 30 June 2009 (UTC)

The relevant section of the article is "Progenitors". --Cryptic C62 · Talk 17:42, 30 June 2009 (UTC)

Thanks for thatStakingsin (talk) 19:28, 30 June 2009 (UTC) —Preceding unsigned comment added by Stakingsin (talk • contribs) 19:20, 30 June 2009 (UTC)

Hyphenation

In other articles, like the one about mass extinction and gamma radiation itself, "gamma ray" is not hyphenated. But in this particular article it is hyphenated. Shouldn't this be changed for consistency? Kutera Genesis (talk) 20:05, 4 September 2009 (UTC)

There are two cases: gamma-ray burst is hyphenated, but 'gamma ray' is not. The grammar rule is that two word adjective phrases need hyphens. For instance, She was a flat-bottom boat, but The boat has a flat bottom.. I hope this helps. Jehochman ^Talk 01:05, 5 September 2009 (UTC)

==beaming==-76.167.77.165 (talk) There's a whole section on beaming. However, nothing in this section explains anything about why beaming might occur.-76.167.77.165 (talk) 06:38, 4 November 2009 (UTC)