Talk:Island of stability/Archive 2
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Archive 1 | Archive 2 |
Local Minimum Binding Energy?
I'm wondering about why the second paragraph states "the binding energy per nucleon will reach a local minimum" for "neutrons and protons completely fill the energy levels of a given shell in the nucleus." The article on binding energy says that binding energy is "the energy required to disassemble a nucleus into free unbound neutrons and protons", so if the binding energy is at a minimum, wouldn't that mean the nucleus would be unstable? Mathfreak11235 (talk) 11:27, 1 January 2008 (UTC)
factual errors
This article has some serious factual errors, and needs attention from an expert. Whoever wrote it doesn't seem to realize that the predicted island(s) of stability occurs at magic numbers which are deformed magic numbers, not spherical magic numbers; you can tell there's a problem because the magic numbers in the text don't match up with the locations of the predicted islands on the 3-d chart. I believe the sentence beginning "Of particular note is Ubh-310 ..." is also completely incorrect, for the following reasons: (1) 126 is a spherical magic number, not a deformed one; (2) it disagrees with the 3-d chart; (3) I believe there is no feasible technique for producing anything this heavy; and (4) I don't think there is any prediction that anything this heavy would be (meta-)stable with respect to fission.--76.93.42.50 (talk) 00:00, 11 January 2008 (UTC)
Beyond and Before
I am kind of confused. Firstly, what lays beyond the Island of Stability? Which element is where? What's before Lead in the map? I think a new map should be made with the following criteria:
It shows beyond ununoctium (including ununseptium)up to element 150 (unpentnilium), and before lead to hydrogen. It shows where every element is located in the map.
Please post your opinions about this below the following line.
—Preceding unsigned comment added by 163.153.102.156 (talk) 17:50, 8 February 2008 (UTC)
- Recent claim for discovery of a stable superheavy element. Ununbibium: Atomic Mass Number 292, Atomic Number 122 and half life of 100+ million years. Wayne (talk) 05:50, 3 May 2008 (UTC)
- Marinov is a known pathological scientist in this field. Also, 122-292 is a particularly ludicrous candidate for a stable element. I would be highly skeptical unless confirmed by an independent source. The way, the truth, and the light (talk) 06:05, 3 May 2008 (UTC)
Roentgenium
I'm confused, because on this page, it gives the longest half-life of Rg as 3.6 seconds, but the Wikipedia page on Rg says its longest half-life lasts about 10 minutes. Which is it? Paul Davidson (talk) 16:03, 9 July 2008 (UTC)
- See below. Kevin Baastalk 14:15, 12 June 2009 (UTC)
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Archive 1 | Archive 2 |
Doubly-magic superheavy nucleus
In the History section, Element 126 is noted as being doubly-magic, and therefore "most likely to have a very long half-life"; in Island of relative stability we have "such superheavy nuclei would undergo alpha decay within microseconds or, less", and element 126 is merely "stable with respect to fission". Is there agreement on current theoretical estimates for half-lives of nuclei around this superheavy island? Bobathon (talk) 13:13, 10 May 2009 (UTC)
- Are you asking if theory agrees with theory? Kevin Baastalk 14:16, 12 June 2009 (UTC)
Editing Needed!
In the long, gray table in this article, listing isotopes for elements 100-118, there needs to be a horizontal line between the isotopes shown for elements 114 and 115. I'd fix this myself, if I knew how, but I do not. Would someone with Wikipedia-editing skills which exceed my own please take care of this? Thanks! RobertAustin (talk) 16:51, 21 July 2009 (UTC)
- It looks fine on my browser. It may be caused by a browser glitch.—Tetracube (talk) 18:22, 21 July 2009 (UTC)
neutron stars
Check out website of Proton-21. Very cool stuff indeed - not much recognized though, which makes it even more intriguing: there is a whole bunch of superheavy, stable elements already synthesized!
- I'd be quite skeptical of that. See also hydrino; just because someone claims something happened doesn't mean it is true. Stonemason89 (talk) 17:32, 5 December 2009 (UTC)
Incorrect caption
The caption and line marked "lead/uranium" is way in the wrong place. Uranium has 92 protons and about 145 neutrons and should be near the middle of the picture, not the left edge.Eregli bob (talk) 06:59, 21 March 2010 (UTC)
Cognitive Dissonance
The colour codes are fighting each other at cross purposes. The code for the first chart (3D map) has stability increasing to warm tones (browns) and the second chart (periodic table) has stability increasing to cool tones (blues). This needs to be fixed. It would probably be easier to fix the second chart. Hu (talk) 18:27, 21 February 2010 (UTC)
- I agree, but I'd like to point out that both color schemes are justified. The 3D map is based on the geographic analogy with an island in a sea, where one would expect the land to be brown and the sea to be blue. At any rate, the user who created the 3D map is inactive. --Smack (talk) 23:15, 11 April 2010 (UTC)
Predicted halflifes
I am not a physicist (a biochemist), but found this very interesting. I was wondering what were the predicted halflives, which this article does not state that clearly, so I read a paper which does some maths showing these nuclei might be stable max for 30min (for Z=114 N=289), while layman's news articles obviously claim they are stable for ever (which would make them extremely useful) instead of being just a curiosity. Could someone make the article clear about that in the intro?--Squidonius (talk) 10:01, 9 October 2009 (UTC)
- "superheavy elements with certain combinations of protons and neutrons arranged in shells in the nucleus would be relatively stable, eventually reaching an "Island of Stability" where their lifetimes could be measured in minutes or days - or even, some optimists think, in millions of years. [...] Based on the ideas of the 1960s, we thought when we got to element 114 we would have reached the Island of Stability. More recent theories suggest enhanced stability at other proton numbers, perhaps 120, perhaps 126. The work we're doing now will help us decide which theories are correct and how we should modify our models. [...] During the last 20 years, many relatively stable isotopes have been discovered that lie between the known heavy element isotopes and the Island of Stability - essentially they can be considered as 'stepping stones' to this island. The question is, how far does the Island extend - from 114 to perhaps 120 or 126? And how high does it rise out the Sea of Instability." [1] (enphasis added) I'll try my hand at amending the intro. -- Limulus (talk) 06:51, 11 October 2009 (UTC)
- I thought the Island did nothing for alpha decay, so we're still talking about very short half lives. kwami (talk) 07:02, 11 October 2009 (UTC)
- I think the Island idea is largely about reduced alpha decay / spontaneous fission (not necessarily approaching actual stability) and that beta decay operates the same way as for lower masses, with beta-decay stable isobars numbering 1 per odd mass number and 1-3 per even mass number. --JWB (talk) 16:37, 11 October 2009 (UTC)
- I thought the Island did nothing for alpha decay, so we're still talking about very short half lives. kwami (talk) 07:02, 11 October 2009 (UTC)
There are 3 modes of structural change of the (heavy) atomic nuclei. They are 1: Beta- decay, where the nucleus emits an electron an decays to a more stable Z+1 atomic structure, 2: Alpha decay, where the atom throws off an alpha (2He4 nucleus) particle, and decays to a Z-2 atomic structure (with the same number of "excess neutrons" (greater than Z number), and 3: where the atomic structure is "fissioned" or fractured into 2 lesser Z number structures. And this decay process is not as closely related to the total numbers of Protons and Neutrons contained in the nucleus as it is to the ability of the composite atomic structure to maintain a dynamic balance of structural properties resulting from the accumulation process. Thus too many extra neutrons will result in B- emission, with an extra neutron changing into a proton. And an inadequacy of extra neutrons will result in an alpha particle emission. And in the heavy element areas with an adequacy of extra neutrons, the less dynamic balanced structure atoms and particularly the EO (even proton/odd neutron)elements, are subject to the occurrence of the atomic splitting or "fission" process. And therefor these decay processes seem to be more closely related to the relationship of the atomic Z number and the extra neutron value (A - 2Z or N - p) value. and there are nuclide charts formulated to better show the Z versus (A - 2Z) value than the standard N versus P charts. SeeUser:JWB/Nuclide chart with skew 1.WFPM (talk) 18:26, 4 September 2010 (UTC)
Article shake-up
I have begun adding, moving and deleting text in this article hoping to breath some new life into it. I feel the following text doesn't have a good place in the current form of the article but at the same time is not without worth.
The feelings of some about the island of stability can be reflected in the following quote:
- "We search for the island of stability because, like Mount Everest, it is there. But, as with Everest, there is profound emotion, too, infusing the scientific search to test a hypothesis. The quest for the magic island shows us that science is far from being coldness and calculation, as many people imagine, but is shot through with passion, longing and romance."
The alpha-decay half-lives of 1700 nuclei with 100 ≤ Z ≤ 130 have been calculated in a quantum tunneling model with both experimental and theoretical alpha-decay Q-values.[2][3][4][5][6][7] The theoretical calculations are in good agreement with the available experimental data.
Maybe after some more work it will be clear where this text fits.
Phancy Physicist (talk) 20:55, 2 December 2010 (UTC)
References
- ^ "Greetings From the Island of Stability", Opinion in the New York Times, February 8, 2004
- ^ P. Roy Chowdhury, C. Samanta, and D. N. Basu (January 26, 2006). "α decay half-lives of new superheavy elements". Phys. Rev. C. 73: 014612. doi:10.1103/PhysRevC.73.014612.
{{cite journal}}
: CS1 maint: multiple names: authors list (link) - ^ C. Samanta, P. Roy Chowdhury and D.N. Basu (2007). "Predictions of alpha decay half lives of heavy and superheavy elements". Nucl. Phys. A. 789: 142–154. doi:10.1016/j.nuclphysa.2007.04.001.
- ^ P. Roy Chowdhury, C. Samanta, and D. N. Basu (2008). "Search for long lived heaviest nuclei beyond the valley of stability". Phys. Rev. C. 77 (4): 044603. doi:10.1103/PhysRevC.77.044603.
{{cite journal}}
: CS1 maint: multiple names: authors list (link) - ^ P. Roy Chowdhury, C. Samanta, and D. N. Basu (2008). "Nuclear half-lives for α -radioactivity of elements with 100 < Z < 130". At. Data & Nucl. Data Tables. 94 (6): 781. doi:10.1016/j.adt.2008.01.003.
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: CS1 maint: multiple names: authors list (link) - ^ P. Roy Chowdhury, D. N. Basu and C. Samanta (January 26, 2007). "α decay chains from element 113". Phys. Rev. C. 75 (4): 047306. doi:10.1103/PhysRevC.75.047306.
- ^ Chhanda Samanta, Devasish Narayan Basu, and Partha Roy Chowdhury (2007). "Quantum tunneling in 277112 and its alpha-decay chain". Journal of the Physical Society of Japan. 76 (12): 124201–124204. doi:10.1143/JPSJ.76.124201.
{{cite journal}}
: CS1 maint: multiple names: authors list (link)
History
I would like to write something on the long lasting search for elements in the island of stability in nature and in experiments only making sense if the element has half live measured in years. I will start wit an article of Hoffmann from 2000.
John Archibald Wheeler in 1955 and Gertrude Scharff Goldhaber in 1957 established the first thoughts. William D. Myers and Wladyslaw J. Swiatecki were able to coin the new word of the island of stability in 1966. From that point on several calculation promised very stable isotopes even with half live in the range of uranium or thorium making them possible primordial elements.
Two possible ways to ways to discover the elements were used. The first one was to produce the isotopes by fusion of smaller nuclei in an particle accelerators. The other method was to search for the element in nature.
References
- Myers, W (1966). "Nuclear masses and deformations". Nuclear Physics. 81: 1. doi:10.1016/0029-5582(66)90639-0.
- . doi:10.1023/A:100679450895900.
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(help) - "Enrichment of the Superheavy Element Rg in Natural Au". 1970. arXiv:1011.6510.
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(help) - Marinov, A.; Rodushkin, I.; Kolb, D.; Pape, A.; Kashiv, Y.; Brandt, R.; Gentry, R. V.; Miller, H. W. (2010). "EVIDENCE FOR THE POSSIBLE EXISTENCE OF A LONG-LIVED SUPERHEAVY NUCLEUS WITH ATOMIC MASS NUMBER A = 292 AND ATOMIC NUMBER Z ≅ 122 IN NATURAL Th". International Journal of Modern Physics E. 19: 131. doi:10.1142/S0218301310014662.
- Marinov, A.; Batty, C. J.; Kilvington, A. I.; Newton, G. W. A.; Robinson, V. J.; Hemingway, J. D. (1971). "Evidence for the Possible Existence of a Superheavy Element with Atomic Number 112". Nature. 229 (5285): 464–7. doi:10.1038/229464a0. PMID 16059298.
- Schultheis, H.; Schultheis, R. (1977). "Prediction of ternary fission rates for element 126". Physical Review C. 15 (4): 1601. doi:10.1103/PhysRevC.15.1601.
- "ON THE DISCOVERY OF THE ELEMENTS 110–112".
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(help) - Kapoor, S S; Ramamurthy, V S; Lal, M; Kataria, S K (1977). "Search for superheavy elements in monazite from beach sands of South India". Pramana. 9 (5): 515. doi:10.1007/BF02846257.
- Lubkin, Gloria B. (1976). "Mica giant halos suggest natural superheavy elements". Physics Today. 29 (8): 17. doi:10.1063/1.3023606.
- Sheline, Raymond K. (1976). "A suggested source of element 126". Zeitschrift f�r Physik A: Atoms and Nuclei. 279 (3): 255. doi:10.1007/BF01408296.
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: replacement character in|journal=
at position 14 (help) - Konovalov, B. (1974). "SHALLOWS OFF THE ISLAND OF STABILITY". Current Digest of the Post-Soviet Press. 26 (44): 26–27.
- Hoffman, D.C. (2000). Journal of Radioanalytical and Nuclear Chemistry. 243: 13. doi:10.1023/A:1006794508959.
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: Missing or empty|title=
(help) - "New Outlook on the Possible Existence of Superheavy Elements in Nature" (PDF).
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: Cite journal requires|journal=
(help) - Frazier, K. (1978). "Superheavy Elements". Science News. 113 (15): 236–238. doi:10.2307/3963006. JSTOR 3963006.
- Ketelle, B.; O'Kelley, G.; Stoughton, R.; Halperin, J. (1976). "Search for Superheavy-Element Decay in Samples of Madagascar Monazite". Physical Review Letters. 37 (26): 1734. doi:10.1103/PhysRevLett.37.1734.
- Marinov, A.; Eshhar, S.; Weil, J.; Kolb, D. (1984). "Consistent Interpretation of the Secondary-Reaction Experiments in W Targets and Prospects for Production of Superheavy Elements in Ordinary Heavy-Ion Reactions". Physical Review Letters. 53 (11): 1120. doi:10.1103/PhysRevLett.53.1120.2.
- Marinov, A.; Eshhar, S.; Weil, J.; Kolb, D. (1984). "Consistent Interpretation of the Secondary-Reaction Experiments in W Targets and Prospects for Production of Superheavy Elements in Ordinary Heavy-Ion Reactions". Physical Review Letters. 52 (25): 2209. doi:10.1103/PhysRevLett.52.2209.
- http://www.phys.huji.ac.il/~marinov/publications/PRL84_42.pdf.
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(help) - Ultra-heavy cosmic rays in the moonA. Proceedings of the Lunar Science Conference.
- search for superheavy elements in lunar material. Proceedings of the Lunar Science Conference.
- Langrock, E; Vater, P.; Brandt, R.; Langrock, G.; Schumer, F.; Schreck, P. (1999). "Attempts in search for superheavy elements in nature II". Radiation Measurements. 31: 563. doi:10.1016/S1350-4487(99)00200-0.
- Langrock, E; Vater, P.; Brandt, R.; Molzahn, D. (1995). "New attempts in search for superheavy elements in nature". Radiation Measurements. 25: 287. doi:10.1016/1350-4487(95)00094-U.
- Herrmann, G (1974). "The Search for Superheavy Elements in Nature". Physica Scripta. 10: 71. doi:10.1088/0031-8949/10/A/011.
- Stephan, C.; Tys, J.; Sowinski, M.; Cieslak, E.; Meunier, M. (1975). "Search for superheavy elements in nature". Journal de Physique. 36 (2): 105. doi:10.1051/jphys:01975003602010500.
- Goncharov, G.N. (2005). "Exotic Nuclei (EXON2004) - Proceedings of the International Symposium": 279. doi:10.1142/9789812701749_0039. ISBN 9789812563927.
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:|chapter=
ignored (help); Cite journal requires|journal=
(help) - Cheifetz, E.; Jared, R.; Giusti, E.; Thompson, S. (1972). "Search for Superheavy Elements in Nature". Physical Review C. 6 (4): 1348. doi:10.1103/PhysRevC.6.1348.
- "SEARCH FOR RELATIVELY STABLE SUPER HEAVY ELEMENTS IN NATURE BY FOSSIL TRACK STUDIES OF CRYSTALS FROM METEORITES AND MOON SURFACE" (PDF).
- Seaborg, Glenn Theodore (1994). "Modern alchemy: selected papers of Glenn T. Seaborg". Chemical & Engineering News. 57 (16): 46. doi:10.1021/cen-v057n016.p046. ISBN 9789810214401.
- Grumann, Jens; Mosel, Ulrich; Fink, Bernd; Greiner, Walter (1969). "Investigation of the stability of superheavy nuclei aroundZ=114 andZ=164". Zeitschrift f�r Physik. 228 (5): 371. doi:10.1007/BF01406719.
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: replacement character in|journal=
at position 14 (help) - Herzberg, R.-D.; Greenlees, P. T.; Butler, P. A.; Jones, G. D.; Venhart, M.; Darby, I. G.; Eeckhaudt, S.; Eskola, K.; Grahn, T. (2006). "Nuclear isomers in superheavy elements as stepping stones towards the island of stability". Nature. 442 (7105): 896–9. doi:10.1038/nature05069. PMID 16929293.
--Stone (talk) 12:37, 5 December 2010 (UTC)
Reference found for "when"
http://dc.cod.edu/cgi/viewcontent.cgi?article=1356&context=essai — Preceding unsigned comment added by 64.245.113.164 (talk) 22:26, 12 April 2012 (UTC)
Image Colors
This isn't that important, but I noticed that the two images in this article (the 3D graph and periodic table) use similar colors to represent stability, but in opposite order. Could one of these images have its colors reversed for consistency? I think the periodic table, being an SVG image, might be particularly easy to modify in such a manner. 138.16.32.85 (talk) 18:44, 6 November 2011 (UTC)
- Since the periodic table adds nothing to this article it would be simpler to remove it and maybe replace it with a Segre chart of the known heavier nuclides. Something like [2] if it could be used. - Rod57 (talk) 21:45, 20 August 2012 (UTC)
Better diagrams needed
Apart from the unsourced 3D diagram at the top we could do with some clearer (non-3d) diagrams of various predictions of the IoS. The various external links include diagrams with IoS Z-N peaks varying between 114-182, 115-182, 118-178, 110-180. eg [3], [4] - Rod57 (talk) 22:31, 20 August 2012 (UTC)
Importance
So what's the theoretical usefulness of isotopes in the island of stability? 108.201.221.204 (talk) 09:19, 7 October 2013 (UTC)
It's probably worth mentioning that the "island of stability" appeared as a critical plot-point in Samuel R. Delany's 1968 novel, Nova. In that book, the vanishingly small existence of "illyrion"--very-high density radioactive elements more or less exactly as described in this article ("trans-300 elements")--provided the high-energy power source needed for faster-than-light space travel. The "quest" of the novel is to obtain a massive haul of illyrion by harvesting the nucleus of an exploding sun, by traveling through the north-south "tunnel" that Delany postulated would be created by the rotational inertia of the exploding star. It's possible that Delany's prediction far predated those of theoretical physics, which would make it an interesting and uncanny prediction on the order of John Brunner's Stand on Zanzibar. Sofa King (talk) 17:56, 11 October 2013 (UTC)
- That might be worth mentioning in Nova (novel) if sourced, but not here. The island of stability has nothing to do with a high-energy power source. These elements are more stable, i.e. less radioactive, and unlikely to be especially dense due to periodicity. And your "far predated" speculation is contradicted by the article - Seaborg introduced the notion in the 1960s, so Delany may even have copied his notion from an existing science concept. --Roentgenium111 (talk) 20:44, 6 May 2014 (UTC)
Half-life disagreement
the color-coded table and the list of half-lives for elements 100-118 don't match up. the table says 113 has a half life of over 1 minutes while the table claims something around one second. many other elements are also incorrect. —Preceding unsigned comment added by 67.148.155.36 (talk) 00:23, 4 April 2009 (UTC)
- I noticed this too. I went to some of the individual element articles to verify, and I think I discovered the cause of the discrepancy: The list shows longest measured half life whereas the colored table uses the longest estimated half life. This confusion can be cleared up by adding columns for estimated longest half life to the list. And I think this should be done. Kevin Baastalk 14:14, 12 June 2009 (UTC)
- To me, the estimated half-lives do not seem very reliable. E.g. for Mt-278, Isotopes_of_meitnerium predicts a half-life of ~30 min, but it really has a half-life of ~8 seconds according to meitnerium (the isotope has recently been created as a decay product of Uus). --Roentgenium111 (talk) 17:44, 11 April 2010 (UTC)
- In fact, in all the "contradicting" cases (109, 111, 112, 113), several of the isotopes claimed to have an estimated half-life of >1 min are now experimentally known to have a much shorter (<1 min) half-life. So all these 4 elements should be coloured purple instead of red. Could someone change the image accordingly? --Roentgenium111 (talk) 23:45, 3 December 2010 (UTC)
- For the ununseptium the halflive is on one side theoretical and on the other side a different value was recorded
https://wiki.riteme.site/wiki/Ununseptium#Nuclear_stability_and_isotopes Wich numbers should be taken? — Preceding unsigned comment added by 193.171.250.130 (talk) 07:04, 15 May 2014 (UTC)
"Straits of instability"
I don't think anyone's drawn this, but the stable "continent" ought to have straits cutting through at Tc (longest-lived isotope 98Tc, t1/2 = 4.2 ×106 a, between Pa and Np) and Pm (longest-lived isotope 145Pm, t1/2 = 17.7 a, between Es and Ac). Below Es, the half-lives are so short that you can't actually see the elements in macroscopic quantities. Double sharp (talk) 03:25, 19 June 2016 (UTC)
- P.S. If the first island is Ra–Cf, then that would mean that the one we are looking for around Fl would be the second, so that the one around element 164 would be the third, no? Double sharp (talk) 03:28, 19 June 2016 (UTC)
New Periodic Table
It is suggested that elements 126 to 134 are completely stable, as File:Extended_periodic_table,_118-218_elements.png used to show (although it was deleted, you can still find the image by looking up "extended periodic table."). Note that although the structure of the table might be incorrect, the marked half-lives of elements 119 to 218 are just a different theory for where the island of stability might be (cyan=stable, green=half life over 4,000,000 years, yellow=half life between 800 and 34,000 years, orange=half life between 1 day and 103 years, red=half life less than 1 day, purple=half life less than several minutes, and dark blue=very short-lived). After all, the image used to be on the Island of Stability category on Commons. 108.66.234.235 (talk) 23:27, 24 November 2016 (UTC)
- It is not so suggested by anyone who actually did the calculations, which expect the island to be somewhat earlier in the known reaches of Z (albeit not in the known reaches of N), around 291,293Cn (predicted half-life 1200 years). Double sharp (talk) 16:32, 6 December 2016 (UTC)
- I thought that the elements on the island of stability (126-134) were completely stable. 108.66.233.20 (talk) 01:58, 13 December 2016 (UTC)
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New article on this issue
Check out the New York times article for new advances on this topic article. Perhaps there is some information here that could be included in the article. Remember (talk) 21:13, 7 April 2010 (UTC)
- No, there is not. NYT is not an "authoritative source" when it comes to science.(Although generally reliable.)173.184.23.223 (talk) 16:55, 29 December 2017 (UTC)
The diagram in the beginning of the article has wrong numbers in the Z(proton number) axis
The Island of stability should be at Z=110, not 120. I never really edited an article myself, can you please fix this? I even found an alternative to that diagram, which is ok. It's this one: http://wiki.riteme.site/wiki/File:Island-of-Stability.png Jackissimus (talk) 14:55, 24 August 2012 (UTC)
Yes, I noticed that too. There seems to be several problems with this diagram. The "Stable mountains - lead to uranium" to the left seems to actually be ytterbium-171 to bismuth-209 (with thorium-232, uranium-235/238 and curium-247 in the "Deformed nuclei" area) and the "island" (with corrected scales) has a single peak at Hassium-288 (108p+180n) while the text indicates several possible peaks at 114p, 120p and 126p+184n. — Preceding unsigned comment added by 84.48.67.188 (talk) 05:53, 8 February 2013 (UTC)
- Same here. The z axis is shifted. It should start at 70 not 80. Even the n axis looks out by a few units.1812ahill (talk) 18:40, 22 March 2014 (UTC)
- It’s amazing. One @Jackissimus: alerted the community about the problem that doesn’t exist, and one @InvaderXan: brought Jackissimus’ mistake into a real SVG image. I could fix the SVG; should I do it? Incnis Mrsi (talk) 19:15, 22 March 2014 (UTC)
- Amazing how quickly you assumed moral high ground here. The island should be at Z=110. The image is confusing. This sentence in the "Island of relative stability" section confirms this: "On the contrary, the nucleus with Z = 110, N = 183 (293Ds) appears to be near the center of a possible 'magic island' (Z = 104–116, N ≈ 176–186)." Furthermore, you can see that the image is wrong when you look at the "bay" at N=130. Its Z location should be between 80 and 90 (see this reference: http://www.frankswebspace.org.uk/ScienceAndMaths/physics/physicsGCE/nuclearImages/islandOfStability.jpg). It's not, the Z axis is shifted throughout this image. If you looked at the location of other stable elements in the image, you would see it. No red element should be beyond Z=100. Think before you post. Jackissimus (talk) 14:16, 8 July 2014 (UTC)
- Please do it. Wikipedia must show real information, not errors. --Zerabat (talk) 12:30, 30 March 2014 (UTC)
- As the image was not updated, I shifted the proton numbers and the SVG to agree with the correct png version. I believe that resolves this issue. Kylegodbey (talk) 16:37, 12 April 2017 (UTC)
- Yes, it does; thank you! Double sharp (talk) 14:28, 17 January 2018 (UTC)
- As the image was not updated, I shifted the proton numbers and the SVG to agree with the correct png version. I believe that resolves this issue. Kylegodbey (talk) 16:37, 12 April 2017 (UTC)
- It’s amazing. One @Jackissimus: alerted the community about the problem that doesn’t exist, and one @InvaderXan: brought Jackissimus’ mistake into a real SVG image. I could fix the SVG; should I do it? Incnis Mrsi (talk) 19:15, 22 March 2014 (UTC)
History
The history section has some problems with the facts. The shell model was not developed in the 1960s, or even in the late 1950s, but actually by Maria Goeppert Mayer and Hans Jensen in the 1940s.
The first sentence of the second paragraph credits Seaborg with introducing the concept of an island of stability, based on a somewhat dubious blog. But in a book co-authored by Seaborg himself he gives others the credit. This seems consistent with most of the sources I have read, which credit Myers, Swiatecki and Meldner (although Oganessian and Rykaczewski give Viola Jr. and Seaborg a share of the credit).
This section is also somewhat haphazard in the way it introduces the concepts, and probably not an easy read for someone new to the subject. I am writing a new version of this section. RockMagnetist(talk) 22:15, 17 February 2019 (UTC)
- @RockMagnetist: Thank you very much for the rewrite, I was wondering if this was necessary, and if so, how to explain it. I was not aware of these inaccuracies as many of the earlier sources that I am aware of do not say much about developments before the 1950s. There are a few small things I tweaked, and I tried to merge some of the shorter sentences. However, I feel that first two paragraphs of § Nuclide stability can be combined into one and are perhaps better explained in valley of stability, to which I added a hatnote - as the properties of lighter elements are not as relevant as the general concepts of binding energy and the nuclear shell model. ComplexRational (talk) 23:46, 17 February 2019 (UTC)
- I'm glad you like the new version. Your tweaks look good, although I tweaked one of them myself to make it flow better. RockMagnetist(talk) 04:30, 18 February 2019 (UTC)
Half-life table
There seem to be plenty of disagreements between half-lives in the three sources for the table in Discoveries. I added one as a footnote, but it might be better to just expand the table with a column for each source. Or maybe one of the sources is more authoritative? RockMagnetist(talk) 00:32, 6 March 2019 (UTC)
@ComplexRational: You seem to think that the correct half-life for Db-268 is 1.2 hours; but Emsley (p. 566) says 29 hours, as does NUBASE 2016, while Oganessian (2016) gives 26 hours - as I said in the note I added to the table. RockMagnetist(talk) 01:11, 6 March 2019 (UTC)
- In general, I try to use the values given in the most recent source (whether it be {{NUBASE 2016}} or a paper from 2016 or later) and keep the values consistent across all articles. In the case of superheavy elements, I find that NUBASE is inconsistent with the most recent publications (e.g. it gives 290Mc as 410 ms and 294Ts as 80 ms, with rather large error margins); however, I am unsure which is preferable because NUBASE gives symmetrical error margins (a ± b) whereas many other papers give a (+b -c). Later I will review the entire list, though I would generally favor a publication if it is from 2016 or later (e.g. for 269Sg, the ref is from 2018) and NUBASE otherwise. BTW, I was fixing the half-life of 268Db; it was mistakenly changed to 1.2 hours by an IP editor. ComplexRational (talk) 01:38, 6 March 2019 (UTC)
- Yes, it was the IP editor's action that drew my attention to the numbers. In the article, you should make it clear how you chose the numbers. RockMagnetist(talk) 02:02, 6 March 2019 (UTC)
- @RockMagnetist: And regarding columns, I'd only recommend it if two sources from approximately the same time give different values or if the most recent source cannot clearly be determined. There is no reason to include, for example, a source from 2010 if it is superseded by a source from 2015. ComplexRational (talk) 01:44, 6 March 2019 (UTC)
Re: the anchor problem: try clicking on NUBASE 2016 in the first Note - it doesn't go anywhere. Is there a way to modify it so it works, using {{NUBASE 2016}}? RockMagnetist(talk) 01:15, 6 March 2019 (UTC)
- As it turns out, {{NUBASE 2016}} has a ref parameter where harvid can be specified; I tested it and it should work now. ComplexRational (talk) 01:38, 6 March 2019 (UTC)
- O.k., that works. RockMagnetist(talk) 02:02, 6 March 2019 (UTC)
Half-lives from various sources
Element | Isotope | Half-life | ||
---|---|---|---|---|
NUBASE 2016 | Most recent publication | Ref | ||
104 | 267Rf | 2.5 h | 1.3 h | [t 1] |
105 | 268Db | 29 hours (1.2 d) | 26 hours (1.1 d) | [t 1] |
106 | 269Sg | 5 min | 14 min | [t 2] |
107 | 270Bh | 3.8 min | 61 seconds (1.02 min) | [t 1] |
108 | 269Hs | 16 s | 9.7 s | [t 3] |
270Hs | 9 s | 7.6 s | [t 3] | |
109 | 278Mt | 7 s | 4.5 s | [t 1] |
110 | 281Ds | 14 s | 12.7 s | [t 1] |
111 | 282Rg | 1.6 min | 100 seconds (1.7 min) | [t 1] |
112 | 285Cn | 32 s | 28 s | [t 1] |
113 | 286Nh | 7 s | 9.5 s | [t 1] |
114 | 289Fl | 2.4 s | 1.9 s | [t 1] |
115 | 290Mc | 410 ms | 650 ms | [t 1] |
116 | 293Lv | 80 ms | 57 ms | [t 1] |
117 | 294Ts | 70 ms | 51 ms | [t 1] |
118 | 294Og | 1.15 ms | 0.69 ms | [t 1] |
References
@RockMagnetist: Here's what I found; there are several inconsistencies and I do not know which values to choose (maybe NUBASE since it is used in all isotopes pages?). I also realized that all the recent sources give a longer half-life for 269Hs than 270Hs, and haven't found anything from 2017 or later. This would necessitate changing the values in all articles related to hassium. ComplexRational (talk) 22:26, 6 March 2019 (UTC)
- It's strange that these sources don't cite each other. That way the NUBASE data are available but you also make the point that some of these numbers aren't written in stone yet. RockMagnetist(talk) 22:59, 6 March 2019 (UTC)
- Indeed it is strange. In that case, which set of values is more appropriate to use (I think the current set is almost identical to the most recent publication column of this table)? ComplexRational (talk) 03:33, 7 March 2019 (UTC)
- Oops, I edited out my suggestion, which is that you use the table above with NUBASE and most recent values. It's better that readers know there is some disagreement. RockMagnetist(talk) 03:52, 7 March 2019 (UTC)
- Indeed it is strange. In that case, which set of values is more appropriate to use (I think the current set is almost identical to the most recent publication column of this table)? ComplexRational (talk) 03:33, 7 March 2019 (UTC)
The basics...
I've been the editor of the Valley of stability article. An obvious omission is apparent in this article, viz., why the term "island of stability"? The answer seems to be, I believe, is that first there was the Valley of Stability, stemming from the obvious set of stable nuclides and the roughly parabolic valley of binding energy, this, then, was surrounded by the "Sea of instability", and then one finally gets to "Island of stability", a small region of stability within the unstable sea. The actual origins of all these term are not known to me, but I believe that is the order. If one goes from "Valley of stability" (a valley is a depression below a surface) to a "Island of stability" (a protuberance above a surface), one has a mixed metaphor...but the physical intent is the same; it should perhaps have been a "pothole of stability", though that is not quite as poetic. I suspect Valley of stability dates to the 1930s, while Island of stability to the 1960s. Anyhow, the origins of this terminology is missing from the article, such that "Island of stability" seems to appear out of nowhere, whereas it has this mixed-metaphor, historical basis. My 2 cents, Bdushaw (talk) 00:20, 8 May 2019 (UTC)
- I don't think we're ever going to know. Many sources attributed the term to Seaborg, but (in my opinion) the most reliable tentatively credited Myers and Świątecki. They didn't explain their choice. RockMagnetist(talk) 00:32, 8 May 2019 (UTC)
Meaning of A
The symbol A appears from nowhere in A = 60. Elsewhere A is the baryon number with A = AZ + N. The use the for continent of stability is as baryon number, but does the A = 60 mean that? In any case it needs an introduction like A or N. Graeme Bartlett (talk) 13:06, 31 July 2019 (UTC)
- @Graeme Bartlett: Yes, it means isotopic mass (Z + N). I added it in the first paragraph of that section. ComplexRational (talk) 13:28, 31 July 2019 (UTC)
- “A + N” makes no sense. Z + N is called the mass number. Isotopic (or, generally, atomic) mass is a related, but distinct quantity. Incnis Mrsi (talk) 14:37, 31 July 2019 (UTC)
- I should have been more careful typing (I really meant Z + N). Anyway symbols should be explained at first use. Graeme Bartlett (talk) 21:27, 31 July 2019 (UTC)
Discovered vs. predicted
Section #Discoveries now has hatnote Main article: Extended periodic table. Isn't this a contradiction?
At the moment, with Og confirmed, all elements of the regular PT (=not extended) are discovered. The extension pertains to non-discovered elements. If predictions are part of this section, the title needs change. Otherwise, the hatnote better be removed/repositioned to an other section. -DePiep (talk) 14:41, 9 November 2019 (UTC)
- @DePiep: It was initially there because of the reference to failed synthesis attempts for elements 119–127. Now that you mention this, it probably is better placed in the section discussing other islands of stability in much heavier, undiscovered elements (some predictions for Z = 126 and Z = 164). ComplexRational (talk) 14:55, 9 November 2019 (UTC)
- Yes, understandable. OK now. -DePiep (talk) 15:09, 9 November 2019 (UTC)
Magic numbers and sphericity
Having magic numbers like 184 for neutrons, with regard to the Island of Stability, is unlikely to be correct. This is because predicted spin-orbit magic number 184 applies solely to SPHERICAL nuclei, and no nucleus heavier than lead-208 is spherical.
The vast majority of atomic nuclei are actually deformed, either in the direction of prolate ellipsoids of rotation, or oblate. Most are prolate. In any case the sequence of magic numbers generally considered apply to spherical nuclei. Deformed nuclei have their own sets of magic numbers.
For spherical nuclei in a simple harmonic oscillator model (lacking such collective effects as spin-orbit coupling), the magic numbers are exactly 2x tetrahedral numbers from the Pascal Triangle. So 2, 8, 20, 40, 70, 112, 168.... This is no accident. The shell sizes here are all doubled triangular numbers- 2, 6, 12, 20, 30, 42, 56, 72... and these then sum to doubled tetrahedral numbers. The doubling appears to be due to counting spin-opposed pairs of nucleons. The harmonic oscillator equation always delivers numbers of stable states (shell sizes) whose values are terms of Pascal Triangle diagonals, and the only determining factor is the dimensionality of the oscillator. More dimensions pushes you deeper into the Triangle, and later diagonals.
One seldom (if ever) seen measure of deformation is the oscillator ratio (OR). In western countries the OR's numerator expresses the relative extent of the matter wave in the polar direction of the ellipsoid, and the denominator that for the equatorial direction. For the sphere the OR is 1:1. Here we have ONE use of each doubled triangular number between every SINGLE magic number. For a prolate ellipsoid of OR 2:1 (twice as long as thick), there is also one doubled triangular number between every magic number, but now each magic number is itself used TWICE successively to generate a magic. So we have components sized 2, 2, 6, 6, 12, 12, 20, 20, 30, 30.... giving summed magics 2, 4, 10, 16, 28, 40, 60, 80, 110, 140.... Same-sized components here come from different shells relative to the default sphere. With OR 3:1, each component is used THRICE successively to generate magic numbers, and there is one doubled triangular number between ever magic. The OR numerator MULTIPLIES the use of each doubled triangular number-sized component.
With oblate nuclei, however, under the harmonic-oscillator only model, things are different. With OR 1:2 (twice as thick as long), each doubled triangular number is used only once, but now the doubled triangular intervals are found not between every single magic, but between every SECOND magic. And with 1:3 between every THIRD, etc. The OR denominator splits usage of the doubled triangular number intervals. A further complication arises at the beginnings of any magic number sequence for an oblate nucleus with a specified OR. Up until there are the OR denominator's worth of magics, the magics themselves are doubled triangular number in size, so 2, 6, 12, 20...., after which the system goes to the splitting rule. When neither the OR's numerator nor denominator are 1, BOTH rules apply to the sequence of magic numbers (with the sequence-initial exceptions noted).
The above applies only to simple harmonic oscillator nuclei. For more realistic models including spin-orbit coupling there is no easy way to work out the sequence of shells except for spheres. And since all nuclei above that of Lead-208 are deformed, predictions of 114 protons and 184 neutrons for the vicinity of the Island of Stability are misplaced.Tetrahedral2020 (talk) 15:52, 21 March 2020 (UTC)
- Thank you for this detailed explanation. I must ask you, though, to put forward sources supporting these claims, otherwise it is considered original research and should not be included in articles in the absence of verifiability from reliable sources.
- I learned a long time ago that simple numerical extrapolations are not always correct, and whatever the article says is directly drawn from the most reliable sources. Most (if not all) of the sources support the magic numbers as they are described in the articles, and they concede that not all predictions are consistent. Since superheavy nuclei are not yet well-characterized, most content is speculative, but there is general consensus that an island of stability for spherical superheavy nuclei exists around Z ~ 114 and N ~ 184 and there is a correlation between closed shells, nuclear shape (spherical vs. deformed), and nuclear stability (e.g. fission barriers). In the absence of sources to the contrary, it seems likely that not all nuclei above lead-208 are necessarily (highly) deformed, and the next spherical doubly magic nucleus will likely be relatively long-lived (even if we don't know exactly which nuclide it is). Although I must admit all this is speculative (the article describes how several predictions have changed with newer models), please provide sources if you disagree with this strongly supported set of predictions. ComplexRational (talk) 17:26, 21 March 2020 (UTC)
This is so cool
Thank you so much to the team of writer(s) who worked so hard to make this a featured article and who got it featured on the front page today! Such a cool topic. I've never learned about nuclear physics before but this was an inspired, fascinating tidbit and it caught my eye on the front page. —Shrinkydinks (talk) 18:24, 21 March 2020 (UTC)
Swapping axis of Z and N very confusing
The first two graphics cover not only different scales, but the Axis of the graphs has been swapped making comparison difficult. Can someone come up with a better graphic, ideally one with identical scaling, and the region in question highlighted, perhaps bordered in yellow?-G (talk) 11:48, 8 April 2020 (UTC)
- I can try to upload a version of the second graphic transformed such that the scales match the first. But the island of stability is outside the range of that one; only known nuclides are shown, and extending the limit of Z or N would be rather difficult. The real reason it's there is to provide context of currently known nuclides; the other graphs "zoom in" on the upper right. I'll see if I can do anything. ComplexRational (talk) 12:45, 8 April 2020 (UTC)
I agree, the axes should all be consistent - very confusing now - please, please fix.151.230.160.24 (talk) 23:35, 17 September 2020 (UTC)
Source of Z=112 stability
The first figure prominently shows several more-stable Copernicium nuclides (Z=112), but the text focuses heavily on Z=114 being a likely magic number. Is there reason to think that the island of stability should be centered around 112 rather than 114? Is this difference due to uncertainties in modelling the band structure of heavy atoms, or are there processes beyond shell closure that contribute to stability? Either way, it might be good to mention 112 more in the text to make it consistent with the figures. --Quantum7 12:15, 9 February 2021 (UTC)
- As I understand it, the occurrence of the island of stability is thought to be more a consequence of the neutron shell closure N = 184 than the proton shell closure (for which predictions vary, and which is widely thought to have a weaker influence anyway; see the KTUY chart). The neutron shell closure would provide additional stability towards alpha decay and spontaneous fission, but then one must also consider beta decay for nuclides off the beta-stability line, so the greatest stability exists for nuclides in the vicinity of N = 184 along the beta-stability line. Additionally, even near the shell closure, nucleon pairing influences alpha decay and SF half-lives (following the pattern for known nuclides), which would mean that the most stable nuclide in the region is probably not even-even.
- Regarding 112, it's not thought to be a shell closure itself and it's not the only prediction mentioned in the article (110, 114, and others are theorized by some authors, and even these give a range of relatively long-lived nuclides), so mentioning it consistently elsewhere might give undue weight (the only consistency is N = 184, which is not specific to a single element). The figures illustrating the 112 predictions are some of the most accessible and illustrative of the general trends, even if predictions for the most stable nuclide vary. ComplexRational (talk) 14:33, 9 February 2021 (UTC)