ADOPTED LEVELS, GAMMAS for 42Si

Authors: Jun Chen and Balraj Singh |  Citation: Nucl. Data Sheets 135, 1 (2016) |  Cutoff date: 31-May-2016 

 Full ENSDF file | Adopted Levels (PDF version) 


Q(β-)=15550 keV SYS(n)= 3630 keV SYS(p)= 24620 keV SYQ(α)= -19940 keV SY
Reference: 2012WA38

References:
  A  9Be(44S,42SiG)  B  C(44S,42SiG)

General Comments:

1990Le03: 42Si identified and produced in 64Ni(48Ca,X) reaction at E=44 MeV/nucleon, followed by a measurement of fragment spectra versus atomic number.

2004Gr20 (also 2004Gr28,2003Gr22): 42Si produced in 9Be(48Ca,X) at E=60 MeV/nucleon, LISE3 spectrometer at GANIL, isotopic identification by energy loss, time-of-flight and magnetic rigidities, double-sided Si strip (DSSD) detectors for residues. Measured (β)(residues) time correlations and half-life using scintillation detectors for β rays. Detailed QRPA calculations. Predictions of Gamow-Teller strengths, Iβ and %β-n for spherical, prolate (ε=+0.3) and oblate (ε=-0.3) shapes. The measured half-life suggests deformed shape when compared with QRPA calculations

2006Fr13 (also 2005Fr19), 2006GrZZ: see 9Be(44S,Xγ) data-set

1999YoZW, from fragmentation of 48Ca beam using 9Be(48Ca,X) and 181Ta(48Ca,X) reactions at 70 MeV/nucleon; measured T1/2 and %β-n; according to the authors, the results are preliminary.

Mass measurement: mass excess=15160 580 (2007Ju03)

Recent theory papers: 2016Li07, 2011Li47, 2011Ka03, 2010Sm02 and 2010Ga15 (shell-model calculations), 2010Ha33 (quadrupole moment), 2009Co21 (half-life), 2009No01 and 2009Zi01 (B(E2))

Q-value: Estimated uncertainties (syst,2012Wa38): ΔQ(β-)=550, ΔS(n)=620, ΔS(p)=780, ΔQ(α)=710 (2012Wa38)

Q-value: S(2n)=5010 550, S(2p)=46620 780, Q(β-n)=13470 510 (syst,2012Wa38)








E(level)
(keV)
XREFJπ(level) T1/2(level)E(γ)
(keV)
Final Levels
     0AB 0+ 12.5 ms 35 
% β- = 100
% β-n = ?
% β-2n = ?
   
   742 8 AB (2+)      742 8 
     0
0+
  2173 14  B (4+)     1431 11 
   742
(2+)
  2774 12 ? B     2032 9 ?
   742
(2+)

E(level): From a least-square fit to γ energies.

Jπ(level): From systematics of even-even nuclei

E(γ): From C(44S,42Siγ).

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Additional Level Data and Comments:

E(level)Jπ(level)T1/2(level)Comments
     00+ 12.5 ms 35 
% β- = 100
% β-n = ?
% β-2n = ?
-n=103 48 (1999YoZW, preliminary result).
E(level): %β-n=103 48 (1999YoZW, preliminary result).
   742(2+)   Low energy of 2+ state and comparison of measured half-life with QRPA calculations (2004Gr20) suggest that 42Si is deformed and that there is collapse of n=28 closed shell at Z=14. But the small production cross section of 42Si in both studies (2006Fr13 and 2006GrZZ) suggest closed shell nature of 42Si.
E(level): Low energy of 2+ state and comparison of measured half-life with QRPA calculations (2004Gr20) suggest that 42Si is deformed and that there is collapse of n=28 closed shell at Z=14. But the small production cross section of 42Si in both studies (2006Fr13 and 2006GrZZ) suggest closed shell nature of 42Si.

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Additional Gamma Comments:

E(level)E(gamma)Comments
   742   742E(γ): 770 19 from 9Be(44S,42Siγ).
  2774  2032E(γ): possible partial feeding of the 2+ state at 742 keV (2012Ta20)

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