Information about Cerium-137:


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Mass-Energy Data:

Atomic Mass:	136.907778	±	0.000051	amu
Excess Mass (Δ):	-85.904567	±	0.047755	MeV
Binding Energy:	1146.299295	±	0.047756	MeV
β^- Decay Energy:	-2.702000	±	0.010000	MeV

"The 1995 update to the atomic mass evaluation" by G.Audi and A.H.Wapstra, Nuclear Physics A595 vol. 4 p.409-480, December 25, 1995.

Radioactive Decay Data:

Spin: 3/2+
Half life: 9.0 h ( 32400 sec., λ = 2.13934×10^-05 s^-1)
Mode of decay:
E.C.
to
137
57
La
(Q = 1.222 MeV)
Meta state at 0.254 Mev
Spin: 11/2- 9.0
Half life: 34.4 h ( 123840 sec., λ = 5.59712×10^-06 s^-1)
Mode of decay: γ (IT) (Q = 0.254 MeV) Branch ratio: 99.22 %
Mode of decay:
E.C.
to
137
57
La
(Q = 1.476 MeV) Branch ratio: 0.78 %
Possible parent nuclides:
E.C. from
137
59
Pr

R.R.Kinsey, et al.,The NUDAT/PCNUDAT Program for Nuclear Data,paper submitted to the 9 th International Symposium of Capture-Gamma_raySpectroscopy and Related Topics, Budapest, Hungary, Octover 1996.Data extracted from NUDAT database (Jan. 14/1999)

Magnetic Dipole Moments and Electric Quadrupole Moments
Ex(kev)	T_1/2	Spin	m(nm)	Q(b)	Ref. Std.	Method	Reference
0	9.0 h	3/2+	0.96(4)			NMR/ON	JPJa 60 845 (91)
			0.90(15)			NO/S	PR 129 1601 (63)
254	34.4 h	11/2-	1.01(4)			NMR/ON	JPJa 60 845 (91)
			0.70(3)			NO/S	PR 143 78 (66)
			0.96(9)			NO/S	PR 121 591 (61)

N. J. Stone, Table of Nuclear Magnetic Dipole and Electric Quadrupole Moments, to be published. 2000 Courtesy of T. Burrows at BNL/NNDC.