We present a comprehensive study of the spectrum of the narrow-line Seyfert 1 galaxy RE J1034+396 , summarizing the information obtained from the optical to X-rays with observations from the William Herschel 4.2m Telescope ( WHT ) , the Hubble Space Telescope ( HST ) , the Extreme UltraViolet Explorer ( EUVE ) , ROSAT , ASCA and Beppo-SAX .
The Beppo-SAX spectra reveal a soft component which is well-represented by two blackbodies with kT _ { eff } =60 eV and 160 eV , mimicking that expected from a hot , optically-thick accretion disc around a low-mass black hole .
This is borne out by our modeling of the optical to X-ray nuclear continuum , which constrains the physical parameters of a NLS1 for the first time .
The models demonstrate that RE J1034+396 is likely to be a system with a nearly edge-on accretion disk ( 60 to 75 ^ { \circ } from the disk axis ) , accreting at nearly Eddington rates ( 0.3 to 0.7 L _ { Edd } ) onto a low mass black hole ( M _ { bh } \sim 2 to 10 \times 10 ^ { 6 } M _ { \odot } ) .
This is consistent with the hypothesis that NLS1s are Seyfert-scale analogies of Galactic Black Hole Candidates .
The unusually high temperature of the big blue bump reveals a flat power-law like continuum in the optical/UV which is consistent with an extrapolation to the hard X-ray power-law , and which we speculate may be similar to the continuum component observed in BL Lac objects in their quiescent periods .
From the Beppo-SAX and ASCA data , we find that the slope of the hard X-ray power-law depends very much on the form of the soft component which is assumed .
For our best-fitting models , it lies somewhere between \alpha =0.7 and 1.3 and thus may not be significantly softer than AGN in general .