We present joint XMM-Newton and NuSTAR observations of the ‘ bare ’ narrow line Seyfert 1 Ton S180 ( z = 0.062 ) , carried out in 2016 and providing the first hard X-ray view of this luminous galaxy .
We find that the 0.4–30 keV band can not be self-consistently reproduced by relativistic reflection models , which fail to account simultaneously for the soft and hard X-ray emission .
The smooth soft excess prefers extreme blurring parameters , confirmed by the nearly featureless nature of the RGS spectrum , while the moderately broad Fe K line and the modest hard excess above 10 keV appear to arise in a milder gravity regime .
By allowing a different origin of the soft excess , the broadband X-ray spectrum and overall spectral energy distribution ( SED ) are well explained by a combination of : ( a ) direct thermal emission from the accretion disc , dominating from the optical to the far/extreme UV ; ( b ) Comptonization of seed disc photons by a warm ( kT _ { e } \sim 0.3 keV ) and optically thick ( \tau \sim 10 ) corona , mostly contributing to the soft X-rays ; ( c ) Comptonization by a standard hot ( kT _ { e } \ga 100 keV ) and optically thin ( \tau < 0.5 ) corona , responsible for the primary X-ray continuum ; and ( d ) reflection from the mid/outer part of the disc .
The two coronae are suggested to be rather compact , with R _ { hot } \la R _ { warm } \la 10 r _ { g } .
Our SED analysis implies that Ton S180 accretes at super-Eddington rates .
This is a key condition for the launch of a wind , marginal ( i.e. , 3.1 \sigma significance ) evidence of which is indeed found in the RGS spectrum .