An 'outside-in' outburst of Aql X-1
An 'outside-in' outburst of Aql X-1
We present optical spectroscopy and optical and infrared photometry of the neutron star soft X-ray transient Aql X--1 during its X-ray outburst of August 1997. By modelling the X-ray, optical, and IR light curves, we find a 3 day delay between the IR and X-ray rise times, analogous to the …