Abstract
This paper reports a new photoluminescence (PL) band in indirect GaAs1xPx that lies between donor-bound and free exciton PL peaks. It has relatively strong X-point phonon sidebands and an asymmetric shape with an abrupt high-energy cutoff. The lifetime varies rapidly over the PL linewidth. Properties of excitons in fluctuating random-alloy potentials are discussed. It is suggested that this line is due to excitons trapped by such potentials.