  We report a new measurement of the cross section for the production of
isolated photons, with transverse energies (ET) above 10 GeV and
pseudorapidities |eta| < 2.5, in p pbar collisions at sqrt{s} = 1.8 TeV. The
results are based on a data sample of 107.6 pb-1 recorded during 1992--1995
with the D0 detector at the Fermilab Tevatron collider. The background,
predominantly from jets which fragment to neutral mesons, was estimated using
the longitudinal shower shape of photon candidates in the calorimeter. The
measured cross section is in good agreement with the next-to-leading order
(NLO) QCD calculation for ET > 36 GeV.
