  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.

Nuclear Experiment;Nuclear Theory