[en] The entry line has been measured for ⁷²Se populated in the reaction ⁵⁸Ni(¹⁶O, 2pγ) at bombarding energies of 54.5, 59.5 and 64.5 MeV, by use of a new technique. The entry line is the locus of energy and spin which results from averaging the population of the γ-emitting region over spin as a function of excitation energy. The excitation energy in ⁷²Se has been measured by summing the γ-energy released in each γ-ray cascade in a large NaI(Tl) (20 x 25 cm) detector. The average spin is simultaneously determined by measuring the γ-ray multiplicity as a function of summed γ-energy. The high efficiency of this method makes it useful in studying the exit channels which originate from the highest angular momentum and excitation energy regions. (author)