Accession Number:

ADA009698

Title:

Doppler Shift Lifetime and Gamma-Ray Angular Measurements in 93NB.

Descriptive Note:

Final rept.,

Corporate Author:

BALLISTIC RESEARCH LABS ABERDEEN PROVING GROUND MD

Personal Author(s):

Report Date:

1975-04-01

Pagination or Media Count:

68.0

Abstract:

Mean lifetimes for four levels in 93Nb have been measured by the Doppler-shift attenuation method. Gamma-ray angular distributions have been measured for the gamma decay of excited levels in 93Nb up to 1127 keV in excitation. The levels were excited by the 90Zralpha, p gamma93Nb reaction at a bombarding energy of 14.77 MeV. Spectra of gamma rays in coincidence with protons were obtained with a 55-cc GeLi detector. Spin assignments obtained from the present results for the low-lying positive-parity levels in 93Nb are in agreement with previous assignments. A spin of 32- has been assigned to a level at 685 keV in excitation and a spin of 52- 32- has been assigned to an 809-keV negative-parity level. Gamma-ray mixing ratios measured for the gamma decay of excited low-lying levels in 93Nb have been combined with lifetime measurements to calculate the electromagnetic transition strengths. The experimental E2 transition strengths are shown to be consistent with those predicted by a weak-coupling model.

Subject Categories:

  • Nuclear Physics and Elementary Particle Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE