  Half-lives of proton emission for Z$\ge$51 nuclei are calculated within a
simple analytical model based on the WKB approximation for the barrier
penetration probability which includes the centrifugal and overlapping effects
besides the electrostatic repulsion. The model has a single free parameter
associated to a Hulthen potential which emulates a Coulomb electrostatic
interaction only at short distance. The agreement with experimental data is
very good for most of the considered nuclei. Theoretical predictions are made
for few cases with uncertain emitting state configuration or incomplete decay
information. The model's assignment of the proton orbital momentum is in
agreement with the differentiation of the experimental data by orbital momentum
values realized with a newly introduced correlation formula.
