Silicon-37

Properties and data of the isotope ³⁷Si.

Contents

Silicon-37 is a radioisotope of the chemical element silicon, which, in addition to the element-specific 14 protons, has 23 neutrons in the atomic nucleus, resulting in the mass number 37. The very short-lived, only artificially producible, unstable and therefore radioactive nuclide has no practical significance; Dealing with ³⁷Si is for academic purposes only.

A report on the discovery of the radioactive nuclide appeared in 1979: According to this, silicon-27 could be produced by strong inelastic reactions induced by irradiating a uranium-236 template with argon-40 ions of an energy of 263 MeV[1].

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

General data

Name of the isotope:Silicon-37; Si-37Symbol:³⁷Si or 3714SiMass number A:37 (= number of nucleons)Atomic number Z:14 (= number of protons)Neutrons N:23Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.6428571428571 (= neutron-proton ratio)Neutron excess (N-Z):9Isotopic mass:36.99295(12) u (atomic weight of Silicon-37)Nuclide mass:36.98527 u (calculated nuclear mass without electrons)Mass excess:-6.56703 MeVMass defect:0.315893516 u (per nucleus)Nuclear binding energy:294.25291479 MeV (per nucleus)
7.95278148 MeV (average binding energy per nucleon)Separation energy:S_N = 2.207(135) MeV (first neutron)
S_P = 19.811(188) MeV (first proton)Half-life:141.0(35) msDecay constant λ:491.59374507798 s^-1Specific activity α:8.223463274231 × 10⁺²⁴ Bq g^-1
2.222557641684 × 10⁺¹⁴ Ci g^-1Spin and parity:
(nuclear angular momentum)(5/2-)Year of discovery:1979

Radioactive Decay

Half-life T_½ = 141.0(35) ms respectively 1.410 × 10^-3 seconds s.

Decay mode	Daughter	Probability	Decay energy
β^-	³⁷P	83(13) %	12.42(12) MeV
β^-, n	³⁶P	17(13) %	5.608(115) MeV
β^-, 2n ?

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 23) and isobaric (same nucleon number A = 37) with Silicon-37. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 23	Isobar A = 37
10	³³Ne
11	³⁴Na	³⁷Na
12	³⁵Mg	³⁷Mg
13	³⁶Al	³⁷Al
14	³⁷Si	³⁷Si
15	³⁸P	³⁷P
16	³⁹S	³⁷S
17	⁴⁰Cl	³⁷Cl
18	⁴¹Ar	³⁷Ar
19	⁴²K	³⁷K
20	⁴³Ca	³⁷Ca
21	⁴⁴Sc	³⁷Sc
22	⁴⁵Ti
23	⁴⁶V
24	⁴⁷Cr
25	⁴⁸Mn
26	⁴⁹Fe
27	⁵⁰Co
28	⁵¹Ni

External data and identifiers

Adopted Levels, Gammas:NuDat 37Si

Literature and References

[1] - P. Auger, T. H. Chiang, J. Galin et al.:
Observation of new nuclides ³⁷Si, ⁴⁰P, ⁴¹S, ⁴²S produced in deeply inelastic reactions induced by ⁴⁰Ar on ²³⁸U.
In: Zeitschrift für Physik A, 289, (1979), DOI 10.1007/BF01415785.

[2] - T. H. Ogunbeku et al.:
First half-life measurement of a low-lying isomer in ³⁷Si.
In: Physical Review C, 108, 034304, (2023), DOI 10.1103/PhysRevC.108.034304.