Evidence of “penetration effects” for the 94 keVK-allowed unhindered transitionin169Tm

Abstract

From the time differential angular correlation measurement of the 94-63 keV cascade in {sup 169}Tm, a pure {ital M1} character of the 94 keV {gamma} ray is suggested in contrast to the 4{percent} {ital E2} admixture observed in conversion coefficient measurements. Our result indicates {open_quotes}penetration effects{close_quotes} on the internal conversion processes for the 94 keV transition. The observation of penetration effects for a {ital K}-allowed unhindered transition is probably the first. The magnetic moment of the 379 keV state has been remeasured, and the value [{mu}=(3.04{plus_minus}0.14){mu}{ital {sub N}}] is in close agreement with the theoretical prediction (4.5{ital {mu}{sub N}}). {copyright} {ital 1997} {ital The American Physical Society}