The quenching of the experimental spectroscopic factor for proton emission from the short-lived $d_{ 3/2}$ isomeric state in $^{ 151m}$Lu was a long-standing problem. In the present work, proton emission from this isomer has been reinvestigated in an experiment at the Accelerator Laboratory of the University of Jyv\"{ a}skyl\"{ a}. The proton-decay energy and half-life of this isomer were measured to be 1295(5) keV and 15.4(8) $\mu$s, respectively, in agreement with another recent study. These new experimental data can resolve the discrepancy in the spectroscopic factor calculated using the spherical WKB approximation. Using the R-matrix approach it is found that the proton formation probability indicates no significant hindrance for the proton decay of $^{ 151m}$Lu.
Categories: nucl-ex nucl-th