Talk:Isotopes of beryllium

This article is part of Wikipedia:Wikiproject Isotopes. Please keep style and phrasings consistent across the set of pages. For later reference and improved reliability, data from all considered multiple sources is collected here. References are denoted by these letters:

• (A) G. Audi, O. Bersillon, J. Blachot, A.H. Wapstra. The Nubase2003 evaluation of nuclear and decay properties, Nuc. Phys. A 729, pp. 3-128 (2003). — Where this source indicates a speculative value, the # mark is also applied to values with weak assignment arguments from other sources, if grouped together. An asterisk after the A means that a comment of some importance may be available in the original.
• (B) National Nuclear Data Center, Brookhaven National Laboratory, information extracted from the NuDat 2.1 database. (Retrieved Sept. 2005, from the code of the popup boxes).
• (C) David R. Lide (ed.), Norman E. Holden in CRC Handbook of Chemistry and Physics, 85th Edition, online version. CRC Press. Boca Raton, Florida (2005). Section 11, Table of the Isotopes. — The CRC uses rounded numbers with implied uncertainties, where this concurs with the range of another source it is treated as exactly equal in this comparison.
• (D) More specific level data from reference B's Levels and Gammas database.
• (E) Same as B but excitation energy replaced with that from D.

  Z   N refs symbol   half-life                   spin              excitation energy
  4   1 ABC |Be-5    |                           |(1/2+)#
  4   2 A   |Be-6    |5.0(3)E-21 s               |0+
  4   2 BC  |Be-6    |[0.092(6) MeV]             |0+
  4   3 AB  |Be-7    |53.22(6) d                 |3/2-
  4   3 C   |Be-7    |53.28 d                    |3/2-
  4   4 A   |Be-8    |67(17)E-18 s               |0+
  4   4 BC  |Be-8    |[6.8(17) eV]               |0+
  4   5 ABC |Be-9    |STABLE                     |3/2-
  4   6 AB  |Be-10   |1.51(6)E+6 a               |0+
  4   6 C   |Be-10   |1.52E+6 a                  |0+
  4   7 ABC |Be-11   |13.81(8) s                 |1/2+
  4   8 AC  |Be-12   |21.50(4) ms                |0+
  4   8 B   |Be-12   |21.49(3) ms                |0+
  4   9 A   |Be-13   |0.5(1) ns                  |(1/2+)
  4   9 B   |Be-13   |2.7(18)E-21 s              |(1/2-)
  4   9 C   |Be-13   |[~1 MeV]                   |
  4  10 A   |Be-14   |4.35(17) ms                |0+
  4  10 B   |Be-14   |4.84(10) ms                |0+
  4  10 C   |Be-14   |4.6 ms                     |0+
  4  11 AB  |Be-15   |<200 ns                    |
  4  12 A*B |Be-16   |<200 ns                    |0+

Femto 15:23, 19 November 2005 (UTC)

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⁵Be half life?

What does it mean that this is blank? Unknown? 72.254.60.149 (talk) 22:26, 9 October 2009 (UTC)

Yes. Lanthanum-138 (talk) 04:42, 4 February 2011 (UTC)

⁸Be half life measure

decay width = 5.57 (25) eV per http://www-nds.iaea.org/relnsd/NdsEnsdf/showensdfdata.jsp?NucNo=8&NucID=BE Using standard decay width to time conversion ħ/Γ = half-life in s and applying error range to the same 1.18 (5) x 10^-16s

So I would say that both values are incorrect as listed currently on the Table for this isotope. 24.8.144.79 (talk) 07:05, 28 April 2013 (UTC)

⁸Be: Shouldn't alpha decay to helium-4 (read: two helium-4 nuclei) be considered fission?

Given that an alpha particle happens to be a helium-4 nucleus in the first place, why is alpha decay ***to*** helium-4 not noted as fission if the daughter nuclei are identical? It would make more sense to note it that way in my opinion (and to that of the average reader) to denote it as such. Thank you. 2602:306:BCA6:AC60:28F0:1D2E:C6A4:796D (talk) 07:23, 24 June 2013 (UTC)

Positron emission

Given that the isotope EO4Be9 is the isotope that supplies the positrons for the Fermi positron acceleration experiments, why isn't there a description of how this is accomplished? Is that due to the decay of a proton or a neutron? And how can a point source contain a +1 electrostatic charge?WFPM (talk) 21:30, 13 November 2013 (UTC)

I have no idea what you're talking about and can see no way that Be-9, our normal Be isotope, could supply positrons. Do you have a link? As for how a point source can be charged it's no harder for a positron than an electron. Ultimately it's still a mystery although QED helps explain what happens to space at such high field strengths very near the point charge. Ultimately the vacuum breaks down into virtual particles that prevent infinite field strengths. SBHarris 08:55, 14 November 2013 (UTC)

It's from the May 1985 National Geographic article about the "Worlds within the Atom", where the element Beryllium is described as the source the "manufactured antiprotons" needed for the proton-antiproton collision experiments. And these "antiprotons would thus be negative unit charged particles with the same mass as the proton. I guess I'm wrong about the production of a positron, because the article says antiproton. But somehow, the interacting positive proton is causing the presumably EO4Be9 atom to emit a negative unit charged particle. And the question is what it would be after it did that? It's a good article, but I don't agree with its drawing portrayal of the nucleus of the EE6c12 Atomic nucleus.WFPM (talk) 03:49, 15 November 2013 (UTC) PS In the Wiki antiproton article, it now says they're using a 29In (Indium) rod as a target. So I guess you have to keep close tabs on these things.WFPM (talk) 02:01, 16 November 2013 (UTC)

At Fermilab now they use a target of Inconel, an iron/nickel/chromium superalloy steel that can withstand sudden thermal shock stresses from proton beam heating. [1] Antiprotons are then focused with a lithium lens, basically a cylinder of lithium with a current running down it. Lithium because it is the least dense electric current conductor, thus minimizing scattering and annihiliation loss as the antiprotons travel through it. It's a fascinating problem in engineering physics, as is anything to do with accelerators. But I see no role for beryllium except its usual one to keep other metals from oxidizing while itself serving as a low density window for various radiations. SBHarris 02:46, 16 November 2013 (UTC)

Okay but that's what the article said. And I'm studying "The hunting of the Quark" By Michael Riordan, which details the history of SLAC and trying to understand how both point particles and quark containing composite particles can wind up with a net unit electric charge. Since it would have to be for different reasons, it sounds like quite a coincidence.WFPM (talk) 00:07, 17 November 2013 (UTC)