ADOPTED LEVELS, GAMMAS for 31Na
Authors: Jun Chen and Balraj Singh | Citation: Nucl. Data Sheets 184, 29 (2022) | Cutoff date: 24-Jun-2022
Full ENSDF file | Adopted Levels (PDF version)
| Q(β-)=15368 keV 14 | S(n)= 4300 keV 15 | S(p)= 1.832×104 keV 25 | Q(α)= -1.531×104 keV 12 | ||
| Reference: 2021WA16 |
| References: | |||
| A | 1H(31Na,31Na’γ) | B | 4He(HI,xγ) |
| C | 12C(32Na,31NaG) | D | 197Au(31Na,31Na’γ) |
| E(level) (keV) | XREF | Jπ(level) | T1/2(level) | E(γ) (keV) | I(γ) | Final Levels | |
| 0.0 | ABCD | 3/2+ | 17.0 ms 4 % β- = 100 % β-n = 39 5 % B-3N < 0.05 % β-2n = 0.7 1 | ||||
| 375.1 7 | ABCD | (5/2+) | 375.1 7 | 100 | 0.0 | 3/2+ | |
| 1162.9 10 | BC | (7/2+) | 787.8 7 | 100 | 375.1 | (5/2+) | |
Additional Level Data and Comments:
| E(level) | Jπ(level) | T1/2(level) | Comments |
| 0.0 | 3/2+ | 17.0 ms 4 % β- = 100 % β-n = 39 5 % B-3N < 0.05 % β-2n = 0.7 1 | μ=+2.298 2 (2000Ke09,2000Ge20) %β-2n=0.9 2 and %β-n=37.1 59 are deduced from %β-n+%β-2n=38 6 (1984La03) and %β-2n/(%β-n+%β-2n)=0.023 5 (1980De26) by neutron counting; %β-2n=0.7 1 and %β-n=40 5 are from 2019Ni04 by γ counting based on known absolute γ-ray intensities in the daughter nuclei 31Al (2005Ma86), 30Al (2008Hi05,2016Ol06), 29Al (1984Gu19) of 31Na β, βn and β2n decays, respectively. Adopted values are weighted averages of above values. Others: %β-n+%β-2n=30 8 (1974Ro31); %β-n=40 12 and %β-2n<1.5 (1984Gu19); %β-=40 14 (2008ReZZ). Upper limit of 0.05% in 1984Gu19 for β-3n decay mode was based on non-observation of long-lived activity of 28Mg (1984Gu19 mention 28Al, which seems a misprint). E(level): %β-2n=0.9 2 and %β-n=37.1 59 are deduced from %β-n+%β-2n=38 6 (1984La03) and %β-2n/(%β-n+%β-2n)=0.023 5 (1980De26) by neutron counting; %β-2n=0.7 1 and %β-n=40 5 are from 2019Ni04 by γ counting based on known absolute γ-ray intensities in the daughter nuclei 31Al (2005Ma86), 30Al (2008Hi05,2016Ol06), 29Al (1984Gu19) of 31Na β, βn and β2n decays, respectively. Adopted values are weighted averages of above values. Others: %β-n+%β-2n=30 8 (1974Ro31); %β-n=40 12 and %β-2n<1.5 (1984Gu19); %β-=40 14 (2008ReZZ). Upper limit of 0.05% in 1984Gu19 for β-3n decay mode was based on non-observation of long-lived activity of 28Mg (1984Gu19 mention 28Al, which seems a misprint). Possible member of Kπ=3/2+ band (2001Pr01). |
| 375.1 | (5/2+) | B(E2)=0.031 +17-13 (2002Pr12,2001Pr01), β2=0.59 10 (2001Pr01) β2 from 197Au(31Na,31Na’γ) reaction. E(level): Possible member of Kπ=3/2+ band (2001Pr01). |
| E(level) | E(gamma) | Comments |
| 375.1 | 375.1 | E(γ): others: 370 12 (2006El03), 376 4 (2010Do05) and 350 20 (2001Pr01), from 1H(31Na,31Na’γ), 12C(32Na,31Naγ) and 197Au(31Na,31Na’γ), respectively. |
| 1162.9 | 787.8 | E(γ): other: 787 8 from 12C(32Na,31Naγ) (2010Do05) |
Mass measurements: 2017Ga20, 2013Ch49, 2007Ju03, 1991Or01, 1991Zh24, 1987Gi05, 1975Th08
Isotopic identification, yield and half-life measurements:
1969Kl08: E=24 GeV, 31Na first identified in Ir(p,X) and U(p,X) reactions.
1972Kl04: U(p,X) E=24 GeV, measured production σ and half-life of 31Na
1972RiZJ: 238U(p,F), measured half-life and yield
1974Ro31: Measured half-life, %β-n
1979We10: Be(48Ca,X) E=212 MeV/nucleon, measured cross section
1979Sy01: 12C(40Ar,X) E=205 MeV/nucleon, measured cross section
1979De02: U(p,X) E=24 GeV, mass spectroscopy
1980De26: Measured two neutron emission
1981ZiZW: 31Na from U(p,X) E=600 MeV, measured beta-delayed neutron activity, deduced strength functions at ISOLDE-CERN facility
1984Gu19: 31Na from Ir(p,X) E(p)=10 GeV, CERN
1984La03: Measured β-delayed neutron emission
1997Ha11: U(p,X) E=1 GeV, measured yield.
1999Dl01, 1997Ta22: Ta(36S,X) E=78 MeV/nucleon; LISE-GANIL facility, measured cross section, half-life
1998NoZW, 1998NoZZ: Ta(40Ar,X) E=95 MeV/nucleon, measured half-life
1999YoZW: Ta(48Ca,X) E=70 MeV/nucleon, measured half-life, %β-n (preliminary results)
2001Pe14: Be(36S,X) E=75 MeV/nucleon; LISE-GANIL facility, measured cross section, half-life, %β-n
2006Tr02: measured yield of 31Na in Be(48Ca,X) E=12.3 MeV/nucleon
2006Kh08: Si(31Na,X) E=30-65 MeV/nucleon, measured cross section, deduced radii, isospin dependence
2012Kw02: 9Be,Ni,181Ta(40Ar,X) E=140 MeV/nucleon at NSCL. Measured fission fragment spectra.
2015Mo17: 9Be(40Ar,X) E=95 MeV/nucleon at RIKEN. Measured momentum distributions of fragments.
2017Ha23: 9Be(40Ar,X) E=69.2 MeV/nucleon at HIRFL, Lanzhou. Measured implant-β(t). Deduced T1/2.
Measurements of hyperfine structure, isotope shifts: 2000Ke09 (β-NMR method), 1996Ke08 (β-NMR method), 1982To05, 1978Hu12 (laser spectroscopy)
Measurements of rms radii: 1998Su07, 1997Su04, 1995Su18
Theoretical calculations: 41 primary references for structure and five for decay characteristics retrieved from the NSR database (www.nndc.bnl.gov/nsr/) are listed under ’document records’.
Q-value: S(2n)=6577 16, S(2p)=42480 530, Q(β-n)=13056 14 (2021Wa16)
Q-value: Q(β-2n)=6716 14 and Q(β-3n)=3053 14 deduced by evaluators from masses in 2021Wa16.