beta-decay studies of Sn135-137 using selective resonance laser ionization techniques
Artikel i vetenskaplig tidskrift, 2002

The decays of the very neutron rich Sn isotopes Sn135-137 were studied at CERN/ISOLDE using isotopic and isobaric selectivity achieved by the use of a resonance ionization laser ion source and mass spectroscopy, respectively. Neutron decay rates, gamma-ray singles, and gamma-gamma coincidence data were collected as a function of time. The half-life (T-1/2) and delayed neutron emission probability (P-n) values of 135 Sn were measured to be 530(20) ms and 21(3)%, respectively. For Sn-136, a T-1/2 of 250(30) ms was determined along with a P-n value of 30(5)%. For Sn-137, a T-1/2 of 190(60) ms and a P-n value of 58(15)% were deduced. Identification of low-energy transitions in Sb-135 was made possible by comparison of laser-on and laser-off gamma-ray spectra. Those data combined with gamma-gamma coincidence spectra were used to construct a level scheme for Sb-135 that includes an unexpectedly low first excited state at 282 keV. A ground state beta branch of 33.2% was measured by following the growth and decay of the Sb-135 daughter. Shell-model calculations are consistent with the observed Sb-135 level structure and can account for a lowered first excited state.

ISOTOPES

STATES

IMPACT

MN

NUCLEAR-STRUCTURE

SB-133

SINGLE-PROTON

ISOLDE

SHELL-MODEL

Författare

J. Shergur

B. A. Brown

V. Fedoseyev

U. Koster

K. L. Kratz

D. Sweryniak

W. B. Walters

A. Wohr

D. Fedorov

M. Hannawald

M. Hjorth-Jensen

V. Mishin

B. Pfeiffer

J. J. Ressler

H. O. U. Fynbo

P. Hoff

H. Mach

Katarina Wilhelmsen Rolander

H. Simon

A. Bickley

Physical Review C - Nuclear Physics

0556-2813 (ISSN) 1089-490X (eISSN)

Vol. 65

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