Isomeric 17/2$sup -$ level and parity mixing in $sup 93$Tc

Journal Article · Mon Mar 01 04:00:00 EST 1976 · Phys. Rev., C, v. 13, no. 3, pp. 1194-1199

OSTI ID:4011810

Brown, B A; Fossan, D B; Lesser, P M.S.; Poletti, A R

The $sup 90$Zr($sup 6$Li, 3n$gamma$$)$$sup 93$Tc reaction has been used in conjunction with pulsed-beam $gamma$, $gamma$$-$$gamma$ coincidence, and $gamma$ angular distribution measurements to investigate a proposed (g$sub 9$$/$$sub 2$$)$$sup 4$$P$$sub 1$$/$$sub 2$17/2$sup -$ isomer in $sup 93$Tc. The isomeric level was found at 2185 keV on the basis of its decay properties and lifetime. The mean lifetime of the 17/2$sup -$ isomeric level was measured to be tau=15.2+-1.0 $mu$sec. The level decays by a 39.7-keV E2 branch (73.7+-1.0%) to the 2145-keV 13/2$sup -$ level and by a 750.7-keV M2/E3 branch (26.3+-1.0%) to the 1434-keV 13/ 2$sup +$ level. An experimental B (E2) 17/2$sup -$$Yields$13/2$sup -$=11.4+-0.9 e$sup 2$fm$sup 4$ is obtained for the E2 branch, impyling an effective charge of e/subp/=2.49+-0.10. To explore possible parity mixing between the nearly degenerate 17/2$sup -$ and 17/2$sup +$ levels, the precise energy separation of these levels was measured to be 0.44+-0.02 keV. On the basis of the observed decay properties, the parity nonconserving matrix element vertical-bar<17/2$sup +$vertical-barH/sub PN/vertical-bar17/2$sup -$>vertical-bar was determined to be less than 0.34 eV. (AIP)

• Research Organization: Department of Physics, State University of New York, Stony Brook, New York 11794
• NSA Number: NSA-33-031809
• OSTI ID: 4011810
• Journal Information: Phys. Rev., C, v. 13, no. 3, pp. 1194-1199, Journal Name: Phys. Rev., C, v. 13, no. 3, pp. 1194-1199; ISSN PRVCA
• Country of Publication: United States
• Language: English

Related Subjects

*TECHNETIUM 93-- ISOMERIC TRANSITIONS
*ZIRCONIUM 90 TARGET-- LITHIUM 6 REACTIONS
*ZIRCONIUM 90-- LITHIUM 6 REACTIONS
642803*
ENERGY LEVELS
N68731* --Physics (Nuclear
Experimental)--Nuclear Properties &amp; Reactions
90 &lt;= A &lt;= 149--Energy Levels &amp; Transitions
N68751 --Physics (Nuclear
Experimental)--Nuclear Properties &amp; Reactions
90 &lt;= A &lt;= 149--Nuclear Reactions &amp; Scattering
SHELL MODELS