Isotopes of gold

Gold (Au) has one stable isotope, ¹⁹⁷Au, and 18 radioisotopes with ¹⁹⁵Au being the most stable with a half-life of 186 days.

Gold has been proposed as a salting material for nuclear weapons (cobalt is another, better-known salting material). A jacket of natural gold, irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, would transmute into the radioactive isotope Au-198 with a half-life of 2.697 days and produce approximately .411 MeV of gamma radiation, significantly increasing the radioactivity of the weapon's fallout for several days. Such a weapon is not known to have ever been built, tested, or used. The highest amount of ¹⁹⁸Au detected in any United States nuclear test was in shot "Sedan" detonated at Nevada Test Site on July 6, 1962. [cite book |last=Miller |first=Richard L. |title=U.S. Atlas of Nuclear Fallout, 1951-1970 |origdate= |origyear= |origmonth= |url=http://books.google.com/books?id=EC03ta0ErHAC&pg=PA340&lpg=PA340&dq=sedan+shot+fallout&source=web&ots=Oo8YinY22a&sig=r3fVc10ZTCcGA_Mrhpt8T71y5Ag&hl=en&sa=X&oi=book_result&resnum=9&ct=result#PPA340,M1 |accessdate=2008-07-19 |edition=Abridged General Reader Edition |volume=1 |year=2002 |month= |publisher=Two Sixty Press |isbn=1881043134 |pages=340 ]

Standard atomic mass: 196.966569(4) u

Table

Notes

* Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses.
* Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC which use expanded uncertainties.

References

* Isotope masses from [http://www.nndc.bnl.gov/amdc/index.html Ame2003 Atomic Mass Evaluation] by G. Audi, A.H. Wapstra, C. Thibault, J. Blachot and O. Bersillon in "Nuclear Physics" A729 (2003).
* Isotopic compositions and standard atomic masses from [http://www.iupac.org/publications/pac/2003/7506/7506x0683.html Atomic weights of the elements. Review 2000 (IUPAC Technical Report)] . "Pure Appl. Chem." Vol. 75, No. 6, pp. 683-800, (2003) and [http://www.iupac.org/news/archives/2005/atomic-weights_revised05.html Atomic Weights Revised (2005)] .
* Half-life, spin, and isomer data selected from these sources. Editing notes on this article's talk page.
** Audi, Bersillon, Blachot, Wapstra. [http://amdc.in2p3.fr/web/nubase_en.html The Nubase2003 evaluation of nuclear and decay properties] , Nuc. Phys. A 729, pp. 3-128 (2003).
** National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the [http://www.nndc.bnl.gov/nudat2/ NuDat 2.1 database] (retrieved Sept. 2005).
** 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.
*It's Elemental - Isotope of the Element Gold [http://education.jlab.org/itselemental/iso079.html]