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New page! Merged proton/neutron drip line

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Just merged the proton drip line and neutron drip line pages. I created the proton drip line page awhile back, but this is what I should have done. Although the two are different because of the Coulomb interaction, it's a unified concept which is basically setting the boundaries for nuclear stability, and there is no reason to have two pages explaining nearly identical information. I will immediately be editing the page to make it more unified, since my first safety step was to copy and paste the articles together before implementing redirection so no information will be lost. I considered also the title 'particle drip line' so if you have a better name for this article, please create the page and make this a redirect. DAID (talk) 12:47, 6 April 2010 (UTC)[reply]

Merge complete. Cleaning and improvements welcome.DAID (talk) 15:33, 6 April 2010 (UTC)[reply]

Improvements Requested

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We need more citations, astrophysical relevance of the proton drip line to the rp-process, general discussion of photodisintegration in astrophysics to distinguish it from the drip lines, some figures, and a section generally outlining the importance of the Coulomb barrier in differentiating the properties and locations of the different drip lines. And since the proton drip line is fairly well known, we should add that information too. DAID (talk) 15:37, 6 April 2010 (UTC)[reply]

Some progress. I also would like to insist that we cite peer reviewed original scientific publication and not some popular science digest. I am happy for the inclusion of any citations before I began working on this wiki, but honestly, sciencedaily is not a proper citation. Sure, it's a reputable source, but we need to cite primary sources in peer reviewed journals for scientific wikis. This needs to be a cleanup tag for wiki if it doesn't already exist, because adding a few citations of popular science magazines to me does not qualify to remove a "this article does not cite sources" tag in science.DAID (talk) 03:56, 7 April 2010 (UTC)[reply]

I find the first sentence misleading. Isn't the dripline the limit of stability against single nucleon decay? As it stands, it seems to imply that beta- emitters are outside the drip line. I guess this is probably a change that should have been done when the neutron- and proton dripline pages were merged. Lsutvs (talk) 11:15, 3 January 2017 (UTC)[reply]

How to display the drip lines

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While we need some figures, we also need a good way to list, say, the known nuclei at the proton drip line. A list in a sentence is preposterous, but I've never used tables on wiki, and I assume it is very different than in html. If I have time, I will figure out hot to make tables. In the mean time, if someone else can do even a small table as a template, then I can do the nuclear physics data input. DAID (talk) 07:07, 7 April 2010 (UTC)[reply]

Although I had this information, I previously refrained from posting it while awaiting some discussion on how to format it. Rather than discuss that point with me in an effort to assist the content of the article, MrFizyx marked the article as needing verification. Thus, I have posted a crap table with the relevant data so maybe someone will see the ugly table and fix it rather than ignoring my discussion in the future. Thanks to anyone who can help! DAID (talk) 06:24, 13 April 2010 (UTC)[reply]

Alpha drip line

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This subject needs some better review, and the description given here could be wrong. This is not a commonly used idea, as, for example, it is not in any text books I have read. I have heard the idea, and the analogy is perfectly reasonable, but its use is very uncommon. This may make it a subject for removal or only a single note rather than its present discussion. I also considered that spontaneous fission may link the proton and neutron drip lines, or that alpha decay may be competing with fission here and there. Since it may be difficult to find an authoritative reference on the matter, then that is also a reason to limit discussion. DAID (talk) 12:21, 7 April 2010 (UTC)[reply]

It's over eight years later and I haven't found the term alpha drip line in any source. Even though the description is reasonable, does this necessitate its removal as WP:OR? ComplexRational (talk) 21:52, 27 December 2018 (UTC)[reply]

Need for additional citations, verification

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This is a reasonable start, but there seems to be much that is inaccurate, misleading, or at the very least, needing citation. For example, to suggest that there are "well established" "known values" of the proton drip line up to A~100 is vague and possibly misleading. Does this mean that the limits of particle stability have been predicted by some model into this mass region or that the proton separation energy of these nuclei have been probed by experiment? It seems that I've read papers by Michael Thoennessen that might be a good place for someone working on this to start. Happy editing. -MrFizyx (talk) 15:55, 9 April 2010 (UTC)[reply]

Actually that's experimentally determined. For example, one might check on the National Nuclear Data Center database; of course I have plans to do this to improve the article with regard to citations and adding more information, but it can be easily verified, in any case. How well the models do in this region I'm not sure off-hand, but it's kind of irrelevant to the experimental facts. What other things are inaccurate, misleading, and need citation. This is one example. For the case given, the most it needs is citation and a listing of the known proton drip line nuclei (see section on that above). In the case that More than 50% of the drip-line is not known, the wording of the article could be revised, but given that we for sure know it up to Z~26 then basically that's half right there. DAID (talk) 01:32, 13 April 2010 (UTC)[reply]
Sorry, the "we for sure know" for up to A=26 is just because I work with light, proton-rich nuclei in the lab. DAID (talk) 02:25, 13 April 2010 (UTC)[reply]
Tag is now removed. According to the Wikipedia standards on verifiability this article never should have been tagged. It states, "The threshold for inclusion in Wikipedia is verifiability, not truth—whether readers can check that material added to Wikipedia has already been published by a reliable source, not whether editors think it is true." It is easy to check with any of the worldwide nuclear data groups that the proton drip line is well established; any reasonable person who was interested could easily verify this fact. For that point, I request all contributors to Wikipedia to make a reasonable effort in an attempt to verify information before indicating articles contain information that is it is likely not possible to verify. In regard to the citations tag, at the time the article was tagged, the article already contained 7 references to peer-reviewed scientific journals, making the general tag generally inappropriate for the article as a whole, which is not very lengthy at present. Finally, there was already a thread discussing the proton drip line nuclei, so beginning a new comment can lead to confusion and a less stream-lined discussion. DAID (talk) 06:21, 13 April 2010 (UTC)[reply]
Perhaps you have a different view of the {{refimprove}} tag. It is not intended to insult the author or to devalue the entire article. I put it there because there are many statements made in the article that are unreferenced. This does not mean that they are untrue or that they cannot be verified. Also, it should be reasonable to expect the author of statements to provide the sources, and not to expect readers to do so. Thanks for your efforts to improve the quality of the article, but I will still feel free to request a citation where having one given will improve it. -MrFizyx (talk) 03:53, 15 April 2010 (UTC)[reply]
I don't think we disagree on the idea of tagging for more references. However, I was annoyed that, after taking two stub articles, combining them, and adding a respectable amount of references, that the whole article would be tagged. This is consistent with the comments which were targeted, as far as I understood, at a specific section and not the article as a whole. I'll agree with the idea that section needed references, but, perhaps as a fault to the tags available, that also questions general verifiability, which I do not believe was ever a matter at stake. To be honest, I couldn't care less if articles I've virtually created are edited to kingdom come. But based on the comments posted, particularly in seeming disregard to recent comments that already existed, it seemed more hostile than helpful to me. On the flip side, I do very significantly edit articles, and I encourage others to do so too, including any I've worked on. But tagging articles, to me, really indicates you ought to have a reasonable knowledge of the article's topic, which was certainly not so clear to me. DAID (talk) 17:26, 19 May 2010 (UTC)[reply]

Proton/Neutron Decay Versus Emission

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Roentgenium111 has changed all instances of 'proton decay' into 'proton emission' to avoid confusion with a term in particle physics. The idea that these two names are used for different phenomena was even removed. Although someone in particle physics may feel different than myself in nuclear physics, nuclear physics has at least as much claim to use the term as in particle physics. The term "proton decay" is not uncommonly used, and so I think any use of the term at all on the article is justified for consistency with literature and texts; of course proton emission is also found, and honestly, I think interchanging the two makes for a better read anyway. Alpha-decay was how the nucleus was discovered, and this goes with the same nomenclature of that term, so any dispute on linguistic terms seems moot to me. So alpha decay might be confused with potential radioactivity of 4He? This is only because there isn't a theory contradicted by experiment indicating that that decay happens (it's only contradicted by experiment). The upper lifetime of the proton half-life is so much larger than the age of the universe. I think it's not fair that an article in nuclear physics is restricted from using a term that's also found in particle physics, and I think using that term here allows someone finding "proton decay" in the literature that is the same as "proton emission" could only be more confused if Wikipedia refuses to recognize this usage. Offhand I don't have references, since this is a pretty common thing; certainly in real life the term is used plenty, so I can only assume it's also found in the literature. This would obviously be the main point for decision. I hope that if instances of this usage in scientific literature can be found, then it is agreed the term should be used on this page.

Unfortunately, this is not an isolated problem. It would be similar to how on the isospin page, there is no mention that a different value is often used in nuclear physics, and only the particle physics definition is given; the best part is I assumed that would be true without ever having read the page, found the page, and that's exactly how it appears. Particle physics mentality overwhelms nuclear physics mentality on most subjects which I've viewed on Wikipedia, and I'd rather not continue the trend on a page that's not even related to particle physics. DAID (talk) 01:53, 13 April 2010 (UTC)[reply]

The first reference[1] I can find to this term are indeed in nuclear physics and not particle physics, meaning proton emission. So even historically if anyone should use a different term, it ought to be those in the particle physics community. Indeed, it is well linked with astrophysics which I emphasized when overhauling this page. The first instance I can find of a similar concept in particle physics is 8 years later, and uses 'protonic decay' [2]; this is consistent with the next paper I can find on the same subject. The first instance I can find in particle physics of this term is in 1960 in this paper. However, even after that time it's usage continues in nuclear physics (paper 1, paper 2). Of course I could continue this search up to the present time, and from 2010 I can find the usage of the term in both disciplines meaning different things. I was pretty sure I had initiated discussion of this on the proton decay page requesting a disambiguation, but apparently I did not do that yet. (Sorry I got lazy properly formatting references for the talk page for later examples.) For those interested, my method is obviously using the ADS Database to query abstracts; searching text of very old papers is much more difficult. In any case, it's very clear this term is used in nuclear physics, and it should be added back in to the article. I will wait to see if there is any discussion before proceeding with the change. DAID (talk) 02:14, 13 April 2010 (UTC)[reply]

References

  1. ^ Fujimoto, Y.; Yamaguchi, Y. (1948). "On the Proton-Decay in Cosmic-ray Stars". Progress of Theoretical Physics. 3: 462.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ^ Fry, W. F.; Schneps, J.; Snow, G. A.; Swami, M. S. (1956). "Mass of the Σ+ Hyperon". Physical Review. 103: 226. doi:10.1103/PhysRev.103.226.{{cite journal}}: CS1 maint: multiple names: authors list (link)

I saw that edit by Roentgenium111 and thought it was a good idea to just use the less ambiguous term. I don't view this as a refusal to acknowledge the alternative expression for the phenomena, but rather as a way to make a clear statement without the tangential discussion of semantics. -MrFizyx (talk) 04:04, 15 April 2010 (UTC)[reply]

I agree. Since Wikipedia articles are meant to be read by the general public, not just experts in one small subfield, specialized jargon that conflicts with other subfields, especially one so closely related as particle physics, are best avoided. Some sensitivity might be given to this more generally: for example, a particle physicist would regard the statement that "alpha decay is the only of the natural radioactive decays that is a particle decay" as pure nonsense: beta decay is certainly a particle decay as well, a purist might include photon emission in this category. The sentence means to say that it is the only one involving nucleon emission, and should say it in a way that avoids ambiguity. In general, much of this article reads like a rough draft, and could be made much more comprehensible to someone not already familiar with the subject. It would be nice if some effort were made to edit it in that direction. Dusty14 (talk) 16:06, 18 April 2010 (UTC)[reply]

I think my attempt to conform with present Wikipedia articles, as they exist, is somewhat at fault. If we want to debate jargon, then the point I think I've clearly made is that Wikipedia is badly in error. To me, it's more convenient to talk about "proton decay" instead of "emission of a proton." The note on nomenclature, I reiterate, was made *because I know Wikipedia has a one-sided view on this matter*. The general population is a concern, but more so is actually being correct. I made disambiguation and clarification because right now Wikipedia only suggests that "proton decay" means one thing, and that one thing is not only theoretical but historically later than nuclear physics ideas of the same name. I guess what bothers me is that if I just wrote the article as it should read (to me), I'd never make that reference and disambiguation. If that was the case, please tell me that you would have noticed and corrected it. I have a lot of pending edits on discussion pages that concern both nuclear and particle physics about how much bias there is towards particle physics, which, according to this comment, extends even to domains of nuclear physics which are not on unrelated to particle physics, but involve terms that were invented first in nuclear physics and have been usurped on Wikipedia by particle physicists. DAID (talk) 17:38, 19 May 2010 (UTC) DAID (talk) 17:41, 19 May 2010 (UTC)[reply]

Copyvio?

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Is it possible that part of this article (added in this edit, specifically) is copied from some text? The sentence "The idea may become more common place with the advent of radioactive ion beam accelerators in the late 1980s, which are allowing nuclear physicists to really probe the limits of nuclear stability" is completely out-of-place in an online encyclopedia article written just a month ago. —Dinoguy1000 (talk · contribs) as 66.116.30.96 (talk) (what's this?) 02:19, 6 May 2011 (UTC)[reply]

Nah, that's my original text. Feel free to change it or move it around, but it wasn't copied from anywhere. I wrote this free-hand. DAID (talk) 05:41, 15 August 2011 (UTC)[reply]

No naturally occurring nuclei that emit neutrons?

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In the section "Nuclei near the drip lines are not common on Earth" there is the following statement: "Although there are no naturally occurring nuclei on Earth which undergo proton emission or neutron emission, such nuclei can be created, for example, in the laboratory with accelerators or naturally in stars." I'm not a scientist, but my understanding is that are natural neutron sources. Am I missing something here, or is this statement simply incorrect? modify 06:52, 25 December 2011 (UTC)[reply]

They're also created inside of reactors; they form that critical .65% of fission products which are delayed in emitting neutrons, and thereby make control of reactors possible.
Quite a belated reply, so sorry.. Spontaneous fission, like uranium isotopes (235, 238) will emit neutrons as a part of fission. However, that is not because they are near the drip line. I like your idea about reactors as an additional example and relevance, though. DAID (talk) 07:49, 8 June 2016 (UTC)[reply]

Rewritten Lede

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There's been a tag here since 2013 rightly suggesting that the lede was inappropriate. I've rewritten to make it more concise. In particular, I've removed much of the parenthetical or textbook-style explanations. In the lede, I assume an understanding of some terms. A reader may have to look these up elsewhere, or to see more detail in the body of the article; however, that allows this new lede to communicate quickly to the reader what exactly a drip line is.

Now, one improvement that someone could make would be to insert a picture of a chart of nuclides, with the drip line indicated. If that's right by the lede, then it's pretty clear what the term means right away. Moishe Rosenbaum (talk) 23:04, 30 December 2016 (UTC)[reply]

List of bound isotopes of light elements

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Z = 0: 1n

Z = 1: 1-3H

Z = 2: 3-4He, 6He, 8He

Z = 3: 6-9Li, 11Li

Z = 4: 7Be, 9-12Be, 14Be

Z = 5: 8B, 10-15B, 17B, 19B

Z = 6: 9-22C

Z = 7: 12-23N

Z = 8: 13-24O

Z = 9: 17-31F

Z = 10: 17-32Ne, 34Ne (33Ne is unbound, see here)

Z = 11: 20-37Na, 39Na

Z = 12: 20-40Mg

I can't find the exact definition of bindness, so I list 26O (half-life 4.5 ps) and 19Mg (5 ps) as unbound. Actually, those N = 128,129 nuclides like 212,213Po seem very much like unbound to me. 14.52.231.91 (talk) 01:11, 16 August 2024 (UTC)[reply]

If I remember correctly, nuclides that can possibly undergo proton emission or neutron emission are counted as unbound. So even nuclides like 147Tm (half-life 0.58 s, branching ratio 15%[1], thus its proton emission partial half-life will be 3.9 seconds!) are still counted as unbound despite long half-lives. Nucleus hydro elemon (talk) 15:00, 16 August 2024 (UTC)[reply]
Thanks! But 26O and 19Mg cannot undergo proton emission or neutron emission; they undergo double proton emission or double neutron emission instead. So I'm not sure about their bindness. 14.52.231.91 (talk) 00:42, 19 August 2024 (UTC)[reply]
I think those decay by 2p emission or 2n emission are also unbound too.
The hardest case is actually 8Be. It is extremely stable to both proton emission and neutron emission, yet it is commonly counted as unbound since it decays to 2 4He in less than 10−16 seconds. I found references about alpha-unbound states,[2] but all of them are about light nuclides rather than heavy nuclides (e.g. 238U and 187Os) that are observed or predicted to undergo alpha decay.
Maybe "bound" is just related to the nuclide's half-life, not their decay mode? I can't find the value that defines the border however. Nucleus hydro elemon (talk) 06:43, 19 August 2024 (UTC)[reply]
I think the most commonly used border is 10-14 seconds, but a few picoseconds for aforementioned 26O and 19Mg look still extremely short... 14.52.231.91 (talk) 00:38, 22 August 2024 (UTC)[reply]

References

  1. ^ Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
  2. ^ doi:10.1103/PhysRevC.79.055805, doi:10.1103/PhysRevC.97.054613, doi:10.1103/PhysRevC.107.055802