Co-ordinating two searchers for an object hidden on an interval

Two unit-speed searchers starting at 0 seek a stationary target hidden according to a known bounded symmetric distribution. The objective is to minimize the expected time for the searchers to return to 0 after one of them has found the target. The paper finds a general optimality condition and uses it to solve the problem when the target has a uniform, triangular, or turncated, exponential distribution. The problem has applications to parallel processing and to the optimal choice of drilling depths in the search for an underground mineral.