Luminosity Dependent Study of the High Mass X-ray Binary Pulsar 4U 0114 + 65 with ASCA

Abstract. Here we report the spectral characteristics of the high and low states of the pulsar 4U 0114 + 65 and examine the change in the para-meters of the spectral model. A power law and a photoelectric absorption by material along the line of sight together with a high energy cut-off suffice to describe the continuum spectrum in both the states. A fluorescence iron line at ∼6.4 keV is present in the high as well as in the low state, though it is less intense in the latter. The photon index, cut-off energy and e-folding energy values hardly show any discernible change over the states. We compare these spectral characteristics as observed with ASCA with those of other satellites. We also compare the spectral characteristics of 4U 0114 + 650 with other X-ray sources which show intensity variation at different time scales