Wikipedia:Reference desk/Archives/Science/2025 August 9

Science desk
< August 8	<< Jul | August | Sep >>	August 10 >

Welcome to the Wikipedia Science Reference Desk Archives
The page you are currently viewing is a transcluded archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.

August 9

W boson

I am having trouble understanding the wikipedia article. Is it saying that a neutrino scatters off a quark with a W boson which then changes the nature of the quark?Rich (talk) 13:15, 9 August 2025 (UTC)[reply]

Whereabouts in which article – W and Z bosons, W boson exchange, or some other? {The poster formerly known as 87.81.230.195} 90.210.150.115 (talk) 18:27, 9 August 2025 (UTC)[reply]

W and Z bosons but I read through the other one too.Rich (talk) 19:16, 9 August 2025 (UTC)[reply]

But which one is the article in which you saw a mention of a neutrino scattering off a quark? This can happen in deep inelastic scattering, in which the force carrier of the interaction is a virtual W or Z boson. You can see a Feynman diagram of this type of interaction in the section Weak interaction § Charged-current interaction, where an electron anti-neutrino interacts with a down quark, resulting in an electron and an up quark. Hopefully, the diagram clarifies things. This article does not use the term "scatter", though, so you must have read this somewhere else.  ​‑‑Lambiam 12:32, 10 August 2025 (UTC)[reply]

I surfed around the web on it. Anyway what is the answer?Rich (talk) 13:27, 10 August 2025 (UTC)[reply]

All the articles mentioned above show the same Feynman diagram, namely the one for neutron decay. Here the (anti)neutrino is not scattered (even for a broad definition of "scattering") but emitted (time flows upwards in the diagram; the inverted arrow on the neutrino's line indicates that it is an antiparticle). You can replace the outgoing antineutrino by an incoming neutrino, so the reaction is ν
_e + n → e⁻
+ p, which is a case of induced neutrino decay. That reaction has been used to detect solar neutrinos, the neutron being embedded in ${\displaystyle ^{37}\mathrm {Cl} }$ , which decays to ${\displaystyle ^{37}\mathrm {Ar} }$ . But you really need to be more specific about which part of which article you are talking about. --Wrongfilter (talk) 14:57, 10 August 2025 (UTC)[reply]

Since n = udd and p = udu, in which the u's are up quarks and the d's are down quarks, the reaction can be pared down to

ν_e + d → e⁻ + u,

with a down quark in and an up quark out. The question whether these are different quarks or the outgoing quark is the same particle as the incoming quark (except that its electric charge got changed) has no physical meaning.

A diagram depicting, explicitly, neutrino–quark scattering can be seen in Figure 1 (b) on page 2 here. This is essentially the same weak interaction, involving a W boson that emerges and disappears in the process.  ​‑‑Lambiam 18:44, 11 August 2025 (UTC)[reply]

Perforated rock

 

Hi, any ideas how these perforations were formed? I think the rock is limestone. Rock was about 40 cm across, lying on a beach at the foot of a sea cliff. Little sea creatures at work? ITookSomePhotos (talk) 18:08, 9 August 2025 (UTC)[reply]

Looks to me like a sea-worn chunk of stony coral, but although I have geologist friends, I'm not one myself, so don't take my word as definitive.

As well as some living corals, fossilised coral is found around the Isle of Wight, particularly in the areas of Caim and Compton Bay, Yaverland, and the beaches between Bouldnor and Hamstead. {The poster formerly known as 87.81.230.195} 90.210.150.115 (talk) 18:23, 9 August 2025 (UTC)[reply]

A number of marine invertibrates will bore into limestone, see this article and this one. Alansplodge (talk) 19:53, 9 August 2025 (UTC)[reply]

I'm wondering about the limestone ID. The only limestone at St Catherine's Point is the chalk, which lies at the top of the sequence. Without knowing the exact ___location, there's no way of being sure, but the holes look more like the result of honeycomb weathering, which would mean that this would more likely be sandstone. The rock that forms the cliff there is a sandstone, but, of course, rocks can fall down from higher up the sequence - see the map at Geology of the Isle of Wight. Mikenorton (talk) 20:41, 14 August 2025 (UTC)[reply]

I earlier took the word "limestone" out of the filename on the basis of the comment above about coral, but forgot to take it out of the description, which I have now done. I don't have the rock with me -- sadly it was too heavy to carry home -- but from my recollection I feel quite doubtful that it was sandstone. Of course I could be wrong. ITookSomePhotos (talk) 18:42, 16 August 2025 (UTC)[reply]