Tantalum-171

Properties and data of the isotope ¹⁷¹Ta.

Content

General data

Name of the isotope:Tantalum-171; Ta-171Symbol:¹⁷¹Ta or 17173TaMass number A:171 (= number of nucleons)Atomic number Z:73 (= number of protons)Neutrons N:98Isotopic mass:170.94448(3) u (atomic weight of Tantalum-171)Nuclide mass:170.9044376 u (calculated nuclear mass without electrons)Mass excess:-51.71655 MeVMass defect:1.475909104 u (per nucleus)Nuclear binding energy:1374.80047492 MeV (per nucleus)
8.03976886 MeV (average binding energy per nucleon)Separation energy:S_N = 9.65(4) MeV (first neutron)
S_P = 2.76(4) MeV (first proton)Half-life:23.3(3) minDecay constant λ:0.00049581343387693 s^-1Specific activity α:1.756387258268 × 10⁺¹⁸ Bq g^-1
47469925.899138 Ci g^-1Spin and parity:
(nuclear angular momentum)(5/2-)Year of discovery:1969

Radioactive Decay

Half-life T_½ = 23.3(3) min (minutes) respectively 1.398 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EE/β⁺	¹⁷¹Hf	100 %	3.71(4) MeV

Parent Nuclides

Direct parent isotope is: ¹⁷¹W.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 98) and isobaric (same nucleon number A = 171) with Tantalum-171. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 98	Isobar A = 171
57	¹⁵⁵La
58	¹⁵⁶Ce
59	¹⁵⁷Pr
60	¹⁵⁸Nd
61	¹⁵⁹Pm
62	¹⁶⁰Sm
63	¹⁶¹Eu
64	¹⁶²Gd
65	¹⁶³Tb	¹⁷¹Tb
66	¹⁶⁴Dy	¹⁷¹Dy
67	¹⁶⁵Ho	¹⁷¹Ho
68	¹⁶⁶Er	¹⁷¹Er
69	¹⁶⁷Tm	¹⁷¹Tm
70	¹⁶⁸Yb	¹⁷¹Yb
71	¹⁶⁹Lu	¹⁷¹Lu
72	¹⁷⁰Hf	¹⁷¹Hf
73	¹⁷¹Ta	¹⁷¹Ta
74	¹⁷²W	¹⁷¹W
75	¹⁷³Re	¹⁷¹Re
76	¹⁷⁴Os	¹⁷¹Os
77	¹⁷⁵Ir	¹⁷¹Ir
78	¹⁷⁶Pt	¹⁷¹Pt
79	¹⁷⁷Au	¹⁷¹Au
80	¹⁷⁸Hg	¹⁷¹Hg
81	¹⁷⁹Tl
82	¹⁸⁰Pb