Talk:Neutron

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Neutron was a Natural sciences good articles nominee, but did not meet the good article criteria at the time. There may be suggestions below for improving the article. Once these issues have been addressed, the article can be renominated. Editors may also seek a reassessment of the decision if they believe there was a mistake.

Article milestones
Date	Process	Result
June 16, 2012	Good article nominee	Not listed

Archives: Index 1, 2, 3, 4

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neutron "mean lifetime" - beam vs bottle values

Perhaps this has been discussed already, but I've stepped in it just now...the controversy regarding the neutron's lifetime. There are discrepancies between the mean lifetimes of ultracold neutrons and "in beam" neutrons. Out of ignorance, I've just modified the numbers to the ultracold neutrons. We should decide what to do...and mention the controversy perhaps? I seek a consensus... Bdushaw (talk) 12:53, 1 April 2024 (UTC)[reply]

From the neutron lifetime article: "On 13 October 2021 the lifetime from the bottle method was updated to τ n = 877.75 s [13][1] increasing the difference to 10 seconds below the beam method value of τ n = 887.7 s [14][15]"...so our values should be updated. 10 s is no small number! Bdushaw (talk) 13:06, 1 April 2024 (UTC)[reply]

I took a stab at including a short paragraph on the issue...there does not seem to be much point in specifying a precise value for the lifetime just yet, given how the measured numbers are changing and conflicting! Bdushaw (talk) 13:42, 1 April 2024 (UTC)[reply]

The Particle Data Group value is the recognized standard and their value should be quoted. I updated the ref. However the current text has derived values so we have no idea if they are correct or not. Johnjbarton (talk) 15:12, 1 April 2024 (UTC)[reply]

But there is no "standard" value... The citation actually talks about averaging the "bottle" values with one of the "beam" values, but those values are different, hence shouldn't be averaged. Meanwhile, both values seem to be changing year by year! Bdushaw (talk) 15:19, 1 April 2024 (UTC)[reply]

Positron capture

I've been working on citations and find myself somewhat stymied for a citation on positron capture. Firstly, although the text in the article associated with the term seems to me correct, "positron capture" is mostly ignored by standard text and references, certainly insofar as giving the basic discussion given in the article. I find, e.g., online course pages with discussion of the reaction. This form of "beta decay" is certainly correct, but unobservable/non-existent in ordinary existence. However, it seems to play a non-negligible role in the stellar formation of the elements. See W.A. Fowler, "The quest for the origin of the Elements", Science, 226, Nov 23, 1984. Perhaps the topic is too far astray for this Neutron article and the whole thing should be removed. Requesting comment! Bdushaw (talk) 07:52, 9 May 2024 (UTC)[reply]

I looked around and also found little. It's possible that the positron-neutron reaction in stars has a different name. My suggestion is just to delete that sentence. If we find a source it can be added back. Johnjbarton (talk) 14:55, 9 May 2024 (UTC)[reply]

I've revised the paragraph, including the citation I gave above. I've removed much of the "improvisational" material. Keeping the mention of "positron" capture in stars supports the mention of nucleosynthesis in stars in the lead (which the article does not yet seem to mention!). Partly, I have a remote association with Fowler, who won the Nobel Prize... Bdushaw (talk) 20:22, 9 May 2024 (UTC)[reply]

Radius

Proton has a charge radius. Is the neutron radius also a charge radius (even though it is neutral overall) ? Can we link to how the radii are defined and measured or derived ? - Rod57 (talk) 11:40, 8 August 2024 (UTC)[reply]