Theory had previously predicted a half-life of 4.6×1019 years. It had been suspected to be radioactive for a long time.[6] The decay produces a 3.14 MeV alpha particle plus thallium-205.[3][4]
Bismuth-209 occurs in the neptunium series decay chain.
If perturbed, it would join in lead-bismuth neutron capture cycle from lead-206/207/208 to bismuth-209, despite low capture cross sections. Even thallium-205, the decay product of bismuth-209, reverts to lead when fully ionized.[8]
Due to its hugely long half-life, for nearly all applications 209Bi can be treated as non-radioactive. It is much less radioactive than human flesh, so it poses no real radiation hazard. Though 209Bi holds the half-life record for alpha decay, it does not have the longest known half-life of any nuclide; this distinction belongs to tellurium-128 (128Te) with a half-life estimated at 7.7 × 1024 years by double β-decay (double beta decay).[9][10][11]
The half-life of 209Bi was confirmed in 2012 by an Italian team in Gran Sasso who reported (2.01±0.08)×1019 years. They also reported an even longer half-life for alpha decay of 209Bi to the first excited state of 205Tl (at 204 keV), was estimated at 1.66×1021 years.[12] Even though this value is shorter than the half-life of 128Te, both alpha decays of 209Bi hold the record of the thinnest natural line widths of any measurable physical excitation, estimated respectively at ΔΕ~5.5×10−43 eV and ΔΕ~1.3×10−44 eV in application of the uncertainty principle[13] (double beta decay would produce energy lines only in neutrinoless transitions, which has not been observed yet).
Because all primordial bismuth is bismuth-209, bismuth-209 is used for all normal applications of bismuth, such as being used as a replacement for lead,[14][15] in cosmetics,[16][17] in paints,[18] and in several medicines such as Pepto-Bismol.[5][19][20] Alloys containing bismuth-209 such as bismuth bronze have been used for thousands of years.[21]
210Po can be manufactured by bombarding 209Bi with neutrons in a nuclear reactor.[22] Only around 100 grams of 210Po are produced each year.[23][22]209Po and 208Po can be made through the proton bombardment of 209Bi in a cyclotron.[24]Astatine can also be produced by bombarding 209Bi with alpha particles.[25][26][27] Traces of 209Bi have also been used to creategold in nuclear reactors.[28][29]
Bismuth-209 is created in the final part of the s-process.[a]
In the red giant stars of the asymptotic giant branch, the s-process (slow process) is ongoing to produce bismuth-209 and polonium-210 by neutron capture as the heaviest elements to be formed,[44] and the latter quickly decays.[44] All elements heavier than it are formed in the r-process, or rapid process, which occurs during the first fifteen minutes of supernovas.[45][44] Bismuth-209 is also created during the r-process.[44]
^Red horizontal lines with a circle in their right ends represent neutron captures; blue arrows pointing up-left represent beta decays; green arrows pointing down-left represent alpha decays; cyan/light-green arrows pointing down-right represent electron captures.
^ abMarcillac, Pierre de; Noël Coron; Gérard Dambier; Jacques Leblanc; Jean-Pierre Moalic (April 2003). "Experimental detection of α-particles from the radioactive decay of natural bismuth". Nature. 422 (6934): 876–878. Bibcode:2003Natur.422..876D. doi:10.1038/nature01541. PMID12712201. S2CID4415582.
^ abKean, Sam (2011). The Disappearing Spoon (and other true tales of madness, love, and the history of the world from the Periodic Table of Elements). New York/Boston: Back Bay Books. pp. 158–160. ISBN978-0-316-051637.
^"Noble Gas Research". Archived from the original on 2011-09-28. Retrieved 2013-01-10. Tellurium-128 information and half-life. Accessed July 14, 2009.
^B. Gunter "Inorganic Colored Pigments” in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2012.
^Madisch A, Morgner A, Stolte M, Miehlke S (December 2008). "Investigational treatment options in microscopic colitis". Expert Opinion on Investigational Drugs. 17 (12): 1829–37. doi:10.1517/13543780802514500. PMID19012499. S2CID72294495.
^Larsen, R. H.; Wieland, B. W.; Zalutsky, M. R. J. (1996). "Evaluation of an Internal Cyclotron Target for the Production of 211At via the 209Bi (α,2n)211At reaction". Applied Radiation and Isotopes. 47 (2): 135–143. doi:10.1016/0969-8043(95)00285-5. PMID8852627.
^ abMunzenberg; Hofmann, S.; Heßberger, F. P.; Reisdorf, W.; Schmidt, K. H.; Schneider, J. H. R.; Armbruster, P.; Sahm, C. C.; Thuma, B. (1981). "Identification of element 107 by α correlation chains". Z. Phys. A. 300 (1): 107–108. Bibcode:1981ZPhyA.300..107M. doi:10.1007/BF01412623. S2CID118312056.
^Hessberger, F. P.; Münzenberg, G.; Hofmann, S.; Agarwal, Y. K.; Poppensieker, K.; Reisdorf, W.; Schmidt, K.-H.; Schneider, J. R. H.; Schneider, W. F. W.; Schött, H. J.; Armbruster, P.; Thuma, B.; Sahm, C.-C.; Vermeulen, D. (1985). "The new isotopes 258105,257105,254Lr and 253Lr". Z. Phys. A. 322 (4): 4. Bibcode:1985ZPhyA.322..557H. doi:10.1007/BF01415134. S2CID100784990.
^Hofmann, S.; Ninov, V.; Heßberger, F. P.; Armbruster, P.; Folger, H.; Münzenberg, G.; Schött, H. J.; Popeko, A. G.; et al. (1995). "The new element 111". Zeitschrift für Physik A. 350 (4): 281–282. Bibcode:1995ZPhyA.350..281H. doi:10.1007/BF01291182. S2CID18804192.
^Hofmann, S.; Heßberger, F. P.; Ackermann, D.; Münzenberg, G.; Antalic, S.; Cagarda, P.; Kindler, B.; Kojouharova, J.; et al. (2002). "New results on elements 111 and 112". The European Physical Journal A. 14 (2): 147–157. Bibcode:2002EPJA...14..147H. doi:10.1140/epja/i2001-10119-x. S2CID8773326.
^Morita, K.; Morimoto, K. K.; Kaji, D.; Goto, S.; Haba, H.; Ideguchi, E.; Kanungo, R.; Katori, K.; Koura, H.; Kudo, H.; Ohnishi, T.; Ozawa, A.; Peter, J. C.; Suda, T.; Sueki, K.; Tanihata, I.; Tokanai, F.; Xu, H.; Yeremin, A. V.; Yoneda, A.; Yoshida, A.; Zhao, Y.-L.; Zheng, T. (2004). "Status of heavy element research using GARIS at RIKEN". Nuclear Physics A. 734: 101–108. Bibcode:2004NuPhA.734..101M. doi:10.1016/j.nuclphysa.2004.01.019.
^Morita, Kosuke; Morimoto, Kouji; Kaji, Daiya; Akiyama, Takahiro; Goto, Sin-Ichi; Haba, Hiromitsu; Ideguchi, Eiji; Kanungo, Rituparna; et al. (2004). "Experiment on the Synthesis of Element 113 in the Reaction 209Bi(70Zn, n)278113". Journal of the Physical Society of Japan. 73 (10): 2593–2596. Bibcode:2004JPSJ...73.2593M. doi:10.1143/JPSJ.73.2593.
^K. Morita; Morimoto, Kouji; Kaji, Daiya; Haba, Hiromitsu; Ozeki, Kazutaka; Kudou, Yuki; Sumita, Takayuki; Wakabayashi, Yasuo; Yoneda, Akira; Tanaka, Kengo; et al. (2012). "New Results in the Production and Decay of an Isotope, 278113, of the 113th Element". Journal of the Physical Society of Japan. 81 (10): 103201. arXiv:1209.6431. Bibcode:2012JPSJ...81j3201M. doi:10.1143/JPSJ.81.103201. S2CID119217928.