element

Information about Cesium-121:


Wikipedia	Neutron Cross Sections	X-Ray Transitions	X-Ray Attenuation

Mass-Energy Data:

Atomic Mass:	120.917184	±	0.000015	amu
Excess Mass (Δ):	-77.142934	±	0.014128	MeV
Binding Energy:	1010.743556	±	0.014129	MeV
β^- Decay Energy:	-6.802021	±	0.303531	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: 128 s ( 128 sec., λ = 0.00541521 s^-1)
Mode of decay:
E.C.
to
121
54
Xe
(Q = 5.400 MeV)
Meta state at 0.068 Mev
Spin: 9/2(+) 128
Half life: 122 s ( 122 sec., λ = 0.00568153 s^-1)
Mode of decay:
E.C.
to
121
54
Xe
(Q = 5.469 MeV) Branch ratio: 83.00 %
Mode of decay: γ (IT) (Q = 0.068 MeV) Branch ratio: 17.00 %
Possible parent nuclides:
E.C. from
121
56
Ba

E.C. +
1
1
p⁺ from
122
57
La

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	2.27 m	3/2+	+0.770(4)		[133Cs]	ABLS	NP A468 1 (87)
			0.79(2)		[133Cs]	AB	NP A292 144 (77)
				+0.838(9) st		ABLS	NP A468 1 (87)
~36	2.02 m	9/2+	+5.41(3)		[133Cs]	ABLS	NP A468 1 (87)
				+2.69(5) st		ABLS	NP A468 1 (87)

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