Editing Sodium (section)

===Isotopes===
{{main|Isotopes of sodium}}
Twenty isotopes of sodium are known, but only <sup>23</sup>Na is stable. <sup>23</sup>Na is created in the [[carbon-burning process]] in stars by fusing two [[carbon]] atoms together; this requires temperatures above 600 megakelvins and a star of at least three solar masses.<ref>{{cite journal|bibcode=1987SvAL...13..214D|title= Sodium Synthesis in Hydrogen Burning Stars|last1=Denisenkov |first1=P. A.|last2=Ivanov|first2=V. V.|volume=13| date=1987|page= 214|journal=Soviet Astronomy Letters}}</ref> Two [[radioactive decay|radioactive]], [[cosmogenic]] isotopes are the byproduct of [[cosmic ray spallation]]: <sup>22</sup>Na has a [[half-life]] of 2.6 years and <sup>24</sup>Na, a half-life of 15 hours; all other isotopes have a half-life of less than one minute.<ref>{{NUBASE 2003}}</ref>

Two [[nuclear isomer]]s have been discovered, the longer-lived one being <sup>24m</sup>Na with a half-life of around 20.2 milliseconds. Acute neutron radiation, as from a nuclear [[criticality accident]], converts some of the stable <sup>23</sup>Na in human blood to <sup>24</sup>Na; the neutron radiation dosage of a victim can be calculated by measuring the concentration of <sup>24</sup>Na relative to <sup>23</sup>Na.<ref>{{cite journal|title=Neutron Activation of Sodium in Anthropomorphous Phantoms|journal=Health Physics| volume=8|issue=4| pages=371–379| date=1962| last1=Sanders| first1=F. W.|last2=Auxier|first2=J. A.| doi= 10.1097/00004032-196208000-00005|pmid=14496815|bibcode=1962HeaPh...8..371S |s2cid=38195963 }}</ref>