Talk:Red-giant branch

Requested move 28 April 2016

 * The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section. 

The result of the move request was: Moved to Red-giant branch. (non-admin closure) Omni Flames   let's talk about it  00:31, 25 May 2016 (UTC)

Red giant branch → Red-giant branch – The term is properly hyphenated, because it is not the giant branch that is red, but the branch of red giants. – JorisvS (talk) 17:29, 28 April 2016 (UTC)
 * For some discussion, see User talk:JorisvS. --JorisvS (talk) 12:18, 1 May 2016 (UTC)
 * Summary of my point now: A "giant branch" exists, which can be seen as short for "giant-star branch". The asymptotic giant branch is the 'branch of giants that is asymptotic'. Originally, all (giant) stars on the 'giant branch' were thought to be red giants. Later, this proved to be false and a qualifier was necessary to indicate specifically the branch of the red giants, not of all giants in general, which resulted in the '(red giant) branch', which should hence be hyphenated. Hence, it should be 'red-giant branch', despite the asymmetry with the non-hyphenated 'asymptotic giant branch' (this is asymmetry stems from the asymmetry in the meaning). --JorisvS (talk) 12:18, 1 May 2016 (UTC)
 * This is a contested technical request (permalink). &mdash; Amakuru (talk) 11:44, 1 May 2016 (UTC)


 * Contested request -  I have reverted the move and listing this for full discussion, following request by Lithopsian.  &mdash; Amakuru (talk) 11:44, 1 May 2016 (UTC)


 * Support the hyphen that clarifies the parse. Here the compound "red giant" modifies "branch", so the compound gets a hyphen to help the reader see that, per MOS:HYPHEN.  While only about 20% of modern books include the hyphen, that's enough to indicate its acceptance; as is typical in many fields, it gets omitted in specialist literature where help with parsing not needed; let's not do that; see WP:SSF.  Dicklyon (talk) 15:02, 1 May 2016 (UTC)


 * Oppose the change. The hyphen is not in common use in this term, nor is it grammatically necessary or helpful.  Two editors have now stated that the compound "red giant" is modifying branch, but this is incorrect.  The modifier is the word "red".  The "red giant branch" is one of two giant branches, or two halves of one giant branch.  The other is the Asymptotic giant branch, originally but now very rarely called the second giant branch (eg. ). The first giant branch is a term still sometimes used (see Pols 1998) for the red giant branch.  Nobody would dream of hyphenating those three terms and nobody should hyphenate the equivalent red giant branch.  To do so is misleading - it gives the impression, as some editors have already mistakenly concluded, that it is actually the "branch of red giants".  It is unfortunate that the current most commonly used name allows for this confusion, but we shouldn't make it worse by hyphenation. Lithopsian (talk) 13:50, 2 May 2016 (UTC)
 * Books and papers do very frequently use "branch of red giants" (see RGB here) as well as the hyphenated "red-giant branch". Your interpretation the red modifies "giant branch" seem peculiar, and is not supported by the usage evidence.  Dicklyon (talk) 14:22, 2 May 2016 (UTC)


 * Oppose – The hyphen is not necessary. The title is syntactically ambiguous without it, but that doesn't make it incorrect. The phrase without the hyphen is used more by the sources, so that's what the title should be. KSF T C 21:34, 2 May 2016 (UTC)
 * I think WP style is generally to prefer less ambiguousity. The hyphen helps the reader experience by removing the syntactic ambiguity.  Frequency in sources is not very relevant to such styling decisions; especially in specialist sources; see WP:SSF.  Dicklyon (talk) 23:17, 2 May 2016 (UTC)
 * Support hyphen. Aside from the fact that it's easy to find the hyphen usage in sources, it would be a profound disservice to readers—especially all those who are not experts and don't see this compound item regularly. When I first saw the notification here, I thought it was a giant branch (entirely plausible). Removing the hyphen is unacceptable. Wikipedia is written for everyone, not just experts who become lazy with typography because they've coded an item through daily exposure to it. Tony   (talk)  03:07, 3 May 2016 (UTC)
 * Support hyphen. Arianewiki1 (talk) 05:08, 3 May 2016 (UTC)
 * Support: This is normal hyphenation in mainstream English. Highly specialized journals (of many sorts) tend to drop these hyphens when using terms of art already understood by their professional, in-that-field readers. Those are not our readership, and insisting on dropping a hyphen that specialists drop when writing for other specialists is the WP:Specialized-style fallacy (the very name of which illustrates the same point as this RM – it's not the specialized fallacy of style, but the fallacy of specialized style, and the hyphen disambiguates).  — SMcCandlish ☺ ☏ ¢ ≽ʌⱷ҅ᴥⱷʌ≼  06:02, 3 May 2016 (UTC)
 * This isn't about correcting the grammar of stupid scientists to help lay readers. This is about changing the meaning of a term.  The whole reason this article has been expanded from a redirect (to Red Giant) is that it specifically is not about the "branch of red giants".  The Red Giant article could express that concept entirely adequately.  If you understand it as having a meaning that should have a hyphen then it may as well still be a simple redirect.  If the article doesn't make the distinction clear then I'll be happy to attempt some rewording. Lithopsian (talk) 13:25, 3 May 2016 (UTC)
 * Yes, please explain. How is the "branch of red giants" different from what you called the "Red Giant Branch" (your caps), and where in the literature can we find that distinction?  This book says they're the same. Dicklyon (talk) 14:41, 3 May 2016 (UTC)


 * Oppose it is more commonly not used. Hyphenation would therefore be incorrect as ti doesn't follow practice. It is unhelpful to the readership as it separates the readers from the actual usage, giving them an unrealistic expectation of the spelling used. -- 70.51.200.96 (talk) 09:51, 3 May 2016 (UTC)
 * Really? Tony   (talk)  11:10, 3 May 2016 (UTC)
 * Support per . –Compassionate727 (T·C) 13:53, 3 May 2016 (UTC)
 * I accidentally voted twice, and my stronger argument is below. –Compassionate727 (T·C) 16:58, 9 May 2016 (UTC)
 * Oppose hyphen, per ADS search results:
 * 1) ADS abstract search for   returns 4311 results.
 * 2) ADS abstract search for   returns 214 results.
 * 3) Google search results are identical and inconclusive.
 * 4) Google trends doesn't have enough information to produce a chart for either term.
 * So it seems that no-hyphen is favored ~ 20:1 over hyphen.  ~ Tom.Reding (talk ⋅dgaf)  14:43, 3 May 2016 (UTC)
 * If results were split closer to 50/50, even 60/40, I'd say go with whichever is grammatically correct (hyphen probably), but WP relies solely on primary, secondary, tertiary sources; it is not a driver of what is "correct", but a passenger. As language/terminology changes, as it appears to be doing here based on overwhelming usage, it isn't up to us to stand in the way, but to reflect that. I would still like to know the non-ADS usage ratio, though, to feel better about this, and I have no problem with having something like "The red giant branch, or red-giant branch, ..." in the lead to reflect what's going on.  ~ Tom.Reding (talk ⋅dgaf)  15:08, 3 May 2016 (UTC)
 * For the latest years on Ngram it's 4:1, not 20:1, but frequencies are largely irrelevant. — kwami (talk) 00:26, 4 May 2016 (UTC)
 * , what's your math on 4:1? Or your reference, if you're not going by ADS?
 * Per my ADS links above:
 * For 2016, it's ~70/2 = 35:1.
 * For 2015, it's ~190/19 = 10:1.
 * For 2014, it's ~153/7 = 21.9:1.  ~ Tom.Reding (talk ⋅dgaf)  15:09, 6 May 2016 (UTC)
 * Found the Ngram link up to 2008. The 4:1 ratio is from 2004-2008, and between 4:1 & 10:1 since the mid 1970s.  ~ Tom.Reding (talk ⋅dgaf)  12:25, 8 May 2016 (UTC)


 * Support. Pace Tom Reding above, we do not follow common usage for stylistic issues, but rather the MOS. Every publisher has an in-house style, and WP is no different. Hyphenation is clearly required per the MOS. If the argument is to abandon the MOS, then the discussion should be held there.  — kwami (talk) 00:17, 4 May 2016 (UTC)
 * ADS represents dozens of separate publishers, so this is hardly a publisher-specific argument.  ~ Tom.Reding (talk ⋅dgaf)  12:24, 4 May 2016 (UTC)
 * Irrelevant. We follow our MOS, not a hodgepodge of others' MOSs. — kwami (talk) 02:54, 7 May 2016 (UTC)


 * Support. Not a lot in it either way, but better hyphenated. It's a bit more precise, removes any ambiguity, and therefore more recognisable. Either is acceptable by usage. Andrewa (talk) 19:37, 6 May 2016 (UTC)
 * Support. There's not a huge difference since redirects are a thing, while having the hyphen clarifies whether giant is associated with red or branch. –Compassionate727 (T·C) 14:06, 6 May 2016 (UTC)
 * Support as per Compassionate727, agreed the hyphen clarifies whether giant is associated with red or branch and it also looks well um nicer? (Although I guess that is simply a personal opinion). Davidbuddy9  Talk 20:36, 9 May 2016 (UTC)
 * Comment. Tip of the red-giant branch is an article about the "tip" of the subject of this article? That already has a hyphen in the title, but what's up with " It uses the luminosity of the brightest red-giant-branch stars "... seems that, as alluded to by som:e comments above, a hyphen could also legitimately be inserted between giant and branch as well – which possibly explains why many don't bother with them at all for this term. wbm1058 (talk) 20:27, 17 May 2016 (UTC)
 * That second hyphen makes sense because in that context the compound noun red-giant branch is used as a modifier of stars. Like ultra-high definition and ultra-high-definition television and such things.  Dicklyon (talk) 22:03, 17 May 2016 (UTC)
 * A number of articles, including the one you describe, have already been edited on the assumption that Red giant branch should be hyphenated. I would suggest that this should not prejudice the outcome of this discussion. Use, or not, of the hyphen in contexts outside Wikipedia might be considered relevant. Use of the entire term red giant branch as a modifier, for example in the phrase "red giant branch star" would be (should be, on strictly grammatical grounds) hyphenated regardless of the outcome of this discussion. This discussion concerns two fairly narrow issues: whether the modifier in red giant branch is "red giant" or simply "red"; and if the modifier is "red giant" then is Wikipedia justified in changing a term that is widely used without the hyphen in order to meet a grammatical or presentational need. Lithopsian (talk) 22:07, 17 May 2016 (UTC)


 * Question: What is a giant branch? That redirects to red giant, but the term is not defined there. Searching for that, Google steers me much towards asymptotic giant branch rather than red giant. wbm1058 (talk) 20:38, 17 May 2016 (UTC)
 * The giant branch can be understood as short for giant-star branch. It is an outdated idea of there being one branch on the Hertzsprung–Russell diagram that contains all giant stars. When it became clear that not all giant stars are red giants, the term was specified, with the asymptotic giant branch being distinguished from the red-giant branch. --JorisvS (talk) 20:46, 17 May 2016 (UTC)
 * giant-star branch, giant star branch... both red links. wbm1058 (talk) 21:14, 17 May 2016 (UTC)
 * That older concept of a giant-star branch can be found in books and magazines, but looks like we didn't have need of such a redirect here. Could do as needed.  Dicklyon (talk) 22:03, 17 May 2016 (UTC)
 * Giant branch is no longer a redirect to red giant since that article does not mention the term. I have made it a disambiguation page referencing the articles about the two giant branches in modern parlance. Lithopsian (talk) 22:22, 17 May 2016 (UTC)


 * Note. I see that there is also a horizontal branch. I'm lost here, and don't know how anyone can fairly assess whether a hyphen is called for here without having some knowledge of the topic. What the heck is a "branch" anyway? ... I think we're dealing with Stellar astronomy and Stellar evolution; hmmm Stellar evolution... Subgiant phase... Red-giant-branch phase... Horizontal branch... Asymptotic-giant-branch phase... Post-AGB. So should we use Red-giant-branch, or if everything is hyphenated, does that make the hyphens pointless? wbm1058 (talk) 21:05, 17 May 2016 (UTC)
 * Hyphens have a purpose. You would not use one in asymptotic giant branch (unless asymptotic giant is a thing, which I think it's not), but when that compound modifies phase, then you would use hyphens to keep it together as a compound modifier.  If you don't understand this role of hyphens in English, why are you even discussing hyphens here?  Dicklyon (talk) 00:07, 18 May 2016 (UTC)
 * A branch in this context is a region of the Hertzsprung–Russell diagram where there is a particular grouping of stars. Historically, it came about from the notion that stars moved along the branches as part of their evolution. The giant branch is, or was since the term is not often seen in modern writing alone without qualifiers, the region of the HR diagram where giants (aka giant stars) are clustered. You can find it used standalone if you look in papers published 40-80 years ago, but rarely since then. The giant branch of that time was implicitly a single branch containing giants and they were all red, whereas now there are two widely-accepted giant branches as well as giants of other colours. There is no article on giant branch and perhaps doesn't need to be, but it deserves a mention somewhere, especially since there are redirects. I'll address that, perhaps sending the redirects to the new article. Lithopsian (talk) 22:07, 17 May 2016 (UTC)


 * So HERE is a picture to help visualize all this. We can view these "branches" in various ways:
 * A horizontal branch, a subgiant branch, an asymptoic-giant and a red-giant branch or
 * A horizontal branch, a subgiant branch, and two (asymptoic and red) giant-branches. wbm1058 (talk) 21:48, 17 May 2016 (UTC)
 * Exactly! In the interests of disclosure, it is worth noting that I drew that picture, although similar images are widely available. Lithopsian (talk) 22:07, 17 May 2016 (UTC)
 * Crazy! English does not hyphenate two-word compound nouns like gaint-branch (except when they are used as modifiers).  And the idea the red and asymptotic are parallel is probably just wrong, too (see usage differences).  Dicklyon (talk) 00:07, 18 May 2016 (UTC)


 * The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.

Values of the Table in Section 2.5
Some of the values in the table in section 2.5 don't really make sense. For example, in the column Radius (R☉) under RGBend, the values are as follows:

M☉=0.6, R☉=207

M☉=1.0, R☉=179

M☉=2.0, R☉=23.5

M☉=5.0, R☉=115

There are a few things like this. Where did the 23.5 come from? Is there any source for the values in this table?

Thanks for any help you can provide, JNeutrino (talk) 01:51, 9 May 2016 (UTC)


 * The reference for the data in the table is here. It got attached to the end of the descriptive text.  Maybe would be better attached to a title for the table? Lithopsian (talk) 15:39, 9 May 2016 (UTC)


 * Yeah, I think that would be better. Sorry I didn't respond sooner; I was busy and forgot to check or put it on my watch list.


 * But I still don't really understand where some of the values in the table are from, because they don't always follow any pattern that would make sense (see the example above, where one might expect as I did that, as mass increased, radius would decrease because the higher the mass, the more material was expelled, and the radii for 0.6 M☉, 1.0 M☉, and 5.0 M☉ support this expectation, but 2.0 M☉ had a much lower radius than any of the others). Lacking the knowledge to read the paper straight through, and lacking the time to look up everything I don't understand in the paper, I was wondering if you could help me by pointing me towards the specific section or part of the paper that the table values were from, so that I could better understand the subject. Sorry for my ignorance, and thanks. JNeutrino (talk) 02:11, 30 June 2016 (UTC)


 * A diagram showing evolutionary tracks for 1, 2, and 5 solar mass stars would clarify why the properties at the end of the RGB appear inconsistent. That is not near the top of my list, so you'll just have to look at the slightly cluttered versions in the reference.  It is explained in the text, but a picture is worth a thousand words (although the explanation only took a few hundred!).  Lithopsian (talk) 16:46, 30 June 2016 (UTC)


 * Ok, thanks. JNeutrino (talk) 16:52, 30 June 2016 (UTC)