Calcium-48

Properties and data of the isotope ⁴⁸Ca.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

Literature

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

General data

Name of the isotope:Calcium-48; Ca-48Symbol:⁴⁸Ca or 4820CaMass number A:48 (= number of nucleons)Atomic number Z:20 (= number of protons)Neutrons N:28Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.4 (= neutron-proton ratio)Neutron excess (N-Z):8Isotopic mass:47.952522654(19) u (atomic weight of Calcium-48)Nuclide mass:47.9415512 u (calculated nuclear mass without electrons)Mass excess:-44.22486 MeVMass defect:0.446595634 u (per nucleus)Nuclear binding energy:416.0011535 MeV (per nucleus)
8.6666907 MeV (average binding energy per nucleon)Separation energy:S_N = 9.9515(22) MeV (first neutron)
S_P = 15.8019(14) MeV (first proton)Half-life:5.3 × 10¹⁹ yearsDecay constant λ:4.147085454658 × 10^-28 s^-1Specific activity α:5.208137334484 × 10^-6 Bq g^-1
1.407604684995 × 10^-16 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Charge radius:3.4771(20) femtometer fmMirror nucleus:Nickel-48Year of discovery:1938

Radioactive Decay

Half-life T_½ = 5.3 × 10¹⁹ years respectively 1.6714080 × 10²⁷ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	⁴⁸Sc	25 %	0.2793 MeV
2β^-	⁴⁸Ti	75 %	4.272 MeV

Parent Nuclides

Direct parent isotopes are: ⁴⁸K, ⁴⁹K.

Occurrence

Comparison of the natural Calcium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):

	Atomic Mass m_a	Quantity	Half-life	Spin
Calcium Isotopic mixture	40.078 u	100 %
Isotope ⁴⁰Ca	39.9625909(2) u	96.941(156) %	stable	0+
Isotope ⁴¹Ca	40.96227792(15) u	[trace]	9.94(15) × 10⁴ years	7/2-
Isotope ⁴²Ca	41.958618(1) u	0.647(23) %	stable	0+
Isotope ⁴⁴Ca	43.955482(2) u	2.086(110) %	stable	0+
Isotope ⁴⁶Ca	45.95369(2) u	0.004(3) %	stable	0+
Isotope ⁴⁸Ca	47.952522654(19) u	0.187(21) %	5.3 × 10¹⁹ years	0+
Isotope ⁴³Ca	42.95876638(24) u	0.135(10) %	stable	7/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 28) and isobaric (same nucleon number A = 48) with Calcium-48. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 28	Isobar A = 48
11	³⁹Na
12	⁴⁰Mg
13	⁴¹Al
14	⁴²Si
15	⁴³P
16	⁴⁴S	⁴⁸S
17	⁴⁵Cl	⁴⁸Cl
18	⁴⁶Ar	⁴⁸Ar
19	⁴⁷K	⁴⁸K
20	⁴⁸Ca	⁴⁸Ca
21	⁴⁹Sc	⁴⁸Sc
22	⁵⁰Ti	⁴⁸Ti
23	⁵¹V	⁴⁸V
24	⁵²Cr	⁴⁸Cr
25	⁵³Mn	⁴⁸Mn
26	⁵⁴Fe	⁴⁸Fe
27	⁵⁵Co	⁴⁸Co
28	⁵⁶Ni	⁴⁸Ni
29	⁵⁷Cu
30	⁵⁸Zn
31	⁵⁹Ga
32	⁶⁰Ge

External data and identifiers

Adopted Levels, Gammas:NuDat 48Ca

Literature and References

[1] - A. Balysh, A. De Silva, V. I. Lebedev et al.:
Double Beta Decay of ⁴⁸Ca.
In: Physical Review Letters, 77, 5186, (1996), DOI 10.1103/PhysRevLett.77.5186.

[2] - Alexander Barabash:
Precise Half-Life Values for Two-Neutrino Double-β Decay: 2020 Review.
In: Universe, 6(10), 159, (2020), DOI 10.3390/universe6100159.