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Isotopes of nobelium

Nobelium (No) has no stable isotopes. A standard atomic mass cannot be given.

Nobelium has also been called eka-ytterbium.

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)
nuclide symbol	excitation energy			half-life	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
²⁴⁸No	102	146	248.08660(32)#	<2 µs	0+
²⁴⁹No	102	147	249.08783(37)#	57(12) µs [54(+15-10) µs]	5/2+#
²⁵⁰No	102	148	250.08751(22)#	5.7(8) µs	0+
²⁵¹No	102	149	251.08901(19)#	0.78(2) s	7/2+#
^251mNo	110(180)# keV			1.7(10) s	9/2-#
²⁵²No	102	150	252.088977(14)	2.27(14) s	0+
²⁵³No	102	151	253.09068(11)#	1.62(15) min	(9/2-)#
^253mNo	129(19) keV			31 µs	5/2+#
²⁵⁴No	102	152	254.090955(19)	51(10) s	0+
^254mNo	500(100)# keV			0.28(4) s	0+
²⁵⁵No	102	153	255.093241(11)	3.1(2) min	(1/2+)
²⁵⁶No	102	154	256.094283(8)	2.91(5) s	0+
²⁵⁷No	102	155	257.096877(23)	25(2) s	(7/2+)
²⁵⁸No	102	156	258.09821(22)#	1.2(2) ms	0+
²⁵⁹No	102	157	259.10103(11)#	58(5) min	(9/2+)#
²⁶⁰No	102	158	260.10264(22)#	106(8) ms	0+
²⁶¹No	102	159	261.10575(32)#	3# h	3/2+#
²⁶²No	102	160	262.10730(48)#	~5 ms	0+
²⁶³No	102	161	263.11055(53)#	20# min
²⁶⁴No	102	162	264.11235(69)#	1# min	0+

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.

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.

Isotopes of mendelevium	Isotopes of nobelium	Isotopes of lawrencium
Index to isotope pages

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Isotopes_of_nobelium". A list of authors is available in Wikipedia.