Isotopes of californium

Californium (Cf)
Has no stable isotopes. A standard atomic mass cannot be given.

Table

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
	excitation energy
Cf-237	98	139	237.06207(54)#	2.1(3) s	5/2+#
Cf-238	98	140	238.06141(43)#	21.1(13) ms	0+
Cf-239	98	141	239.06242(23)#	60(30) s [39(+37-12) s]	5/2+#
Cf-240	98	142	240.06230(22)#	1.06(15) min	0+
Cf-241	98	143	241.06373(27)#	3.78(70) min	7/2-#
Cf-242	98	144	242.06370(4)	3.49(15) min	0+
Cf-243	98	145	243.06543(15)#	10.7(5) min	(1/2+)
Cf-244	98	146	244.066001(3)	19.4(6) min	0+
Cf-245	98	147	245.068049(3)	45.0(15) min	(5/2+)
Cf-246	98	148	246.0688053(22)	35.7(5) h	0+
Cf-247	98	149	247.071001(9)	3.11(3) h	(7/2+)#
Cf-248	98	150	248.072185(6)	333.5(28) d	0+
Cf-249	98	151	249.0748535(24)	351(2) a	9/2-
Cf-249m	144.98(5) keV			45(5) µs	5/2+
Cf-250	98	152	250.0764061(22)	13.08(9) a	0+
Cf-251	98	153	251.079587(5)	900(40) a	1/2+
Cf-252	98	154	252.081626(5)	2.645(8) a	0+
Cf-253	98	155	253.085133(7)	17.81(8) d	(7/2+)
Cf-254	98	156	254.087323(13)	60.5(2) d	0+
Cf-255	98	157	255.09105(22)#	85(18) min	(7/2+)
Cf-256	98	158	256.09344(32)#	12.3(12) min	0+

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 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 Atomic weights of the elements. Review 2000 (IUPAC Technical Report). Pure Appl. Chem. Vol. 75, No. 6, pp. 683-800, (2003) and 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. 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 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.