PULSE PHASE SPECTROSCOPY OF A-0535+26 DURING ITS 1994 GIANT OUTBURST OBSERVED WITH OSSE

We present pulse phase spectroscopy of A 0535+26 in the energy range 3 5-200 keV from OSSE observations of its giant outburst in 1994. We dis cuss the phase dependence of the continuum parameters and the cyclotro n resonance feature (CRF) at 110 keV already found in the phase averag ed spectrum. We find that a CRF is required at every phase. The behavi our of the line parameters with phase and the pulse shape indicate tha t the emission occurs in a pencil-beam geometry.