Observations of Hercules X-1 by the Extreme Ultraviolet Explorer ( EUVE ) covering low state and the early part of the Short High state are reported here .
This is the first EUV observation of this part of the 35-day cycle of Her X-1 .
The low state portion of the EUV light curve ( prior to the start of the Short High state ) has similar properties as that following the end of the Short High state ( [ Leahy & Marshall 1999 ] ) .
This is evidence that the low state EUV emission is primarily due to EUV reflection from the companion star HZ Her .
The EUV lightcurve during the Short High state is pulsed and closely resembles the average 2-12 keV X-ray Short High state lightcurve indicating that the EUV emission , like the X-ray emission , originates near the neutron star .
The Short High state EUV spectrum is consistent with a blackbody of temperature \simeq 0.13 keV and radius \simeq 230 km .
The Short High state EUV spectrum and pulse shape are similar to that in the soft X-rays ( 0.1 - 1 keV ) .
The most likely origin of the EUV emission is reprocessed X-rays from the inner edge of the accretion disk , and the radius of the inner edge of the accretion disk is likely to be small , consistent with that determined from analysis of the X-ray pulse shape evolution ( [ Scott , Leahy & Wilson 2000 ] ) .