Cerium-134

Properties and data of the isotope ¹³⁴Ce.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

Literature

Cerium-134 is a radioisotope of the chemical element cerium, which has 76 neutrons in its atomic nucleus in addition to the element-specific 58 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 134. The very short-lived, only artificially produced, unstable and thus radioactive nuclide has no practical significance; the study of ¹³⁴Ce is exclusively for academic purposes.

The discovery of Cer-134 was first reported in 1951. The isotope was formed by proton bombardment of lanthanum oxide with proton energies between 60 and 80 MeV in the reaction ¹³⁹La(p,6n)¹³⁴Ce. Identification was based on absorption curves and measurements with magnetic counters. The assignment was based on the growth of the characteristic activity of the daughter nuclide lanthanum-134 during the decay of cerium activity, which clearly demonstrated the existence of the isotope [1].

See also: List of individual Cerium isotopes (and general data sources).

General data

Name of the isotope:Cerium-134; Ce-134Symbol:¹³⁴Ce or 13458CeMass number A:134 (= number of nucleons)Atomic number Z:58 (= number of protons)Neutrons N:76Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.3103448275862 (= neutron-proton ratio)Neutron excess (N-Z):18Isotopic mass:133.908928(22) u (atomic weight of Cerium-134)Nuclide mass:133.8771126 u (calculated nuclear mass without electrons)Mass excess:-84.83302 MeVMass defect:1.203457472 u (per nucleus)Nuclear binding energy:1121.01341442 MeV (per nucleus)
8.36577175 MeV (average binding energy per nucleon)Separation energy:S_N = 10.486(26) MeV (first neutron)
S_P = 6.627(35) MeV (first proton)Half-life:3.16(4) dDecay constant λ:2.538777472163 × 10^-6 s^-1Specific activity α:1.149539514992 × 10⁺¹⁶ Bq g^-1
310686.35540343 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:1951

Radioactive Decay

Half-life T_½ = 3.16(4) d respectively 2.73024 × 10⁵ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC	¹³⁴La		0.386(29) MeV

Parent Nuclides

Direct parent isotope is: ¹³⁴Pr.

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
^134mCe	3208.6(4) keV	308(5) ns	10+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 76) and isobaric (same nucleon number A = 134) with Cerium-134. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 76	Isobar A = 134
42	¹¹⁸Mo
43	¹¹⁹Tc
44	¹²⁰Ru
45	¹²¹Rh
46	¹²²Pd
47	¹²³Ag
48	¹²⁴Cd	¹³⁴Cd
49	¹²⁵In	¹³⁴In
50	¹²⁶Sn	¹³⁴Sn
51	¹²⁷Sb	¹³⁴Sb
52	¹²⁸Te	¹³⁴Te
53	¹²⁹I	¹³⁴I
54	¹³⁰Xe	¹³⁴Xe
55	¹³¹Cs	¹³⁴Cs
56	¹³²Ba	¹³⁴Ba
57	¹³³La	¹³⁴La
58	¹³⁴Ce	¹³⁴Ce
59	¹³⁵Pr	¹³⁴Pr
60	¹³⁶Nd	¹³⁴Nd
61	¹³⁷Pm	¹³⁴Pm
62	¹³⁸Sm	¹³⁴Sm
63	¹³⁹Eu	¹³⁴Eu
64	¹⁴⁰Gd	¹³⁴Gd
65	¹⁴¹Tb
66	¹⁴²Dy
67	¹⁴³Ho
68	¹⁴⁴Er
69	¹⁴⁵Tm