| Autor: |
Buisson, DJK, Parker, ML, Kara, E, Vasudevan, RV, Lohfink, AM, Pinto, C, Fabian, AC, Ballantyne, DR, Boggs, SE, Christensen, FE, Craig, WW, Farrah, D, Hailey, CJ, Harrison, FA, Ricci, C, Stern, D, Walton, DJ, Zhang, WW |
| Předmět: |
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| Popis: |
We present two new NuSTAR observations of the narrow line Seyfert 1 (NLS1) galaxy Mrk 766 and give constraints on the two scenarios previously proposed to explain its spectrum and that of other NLS1s: relativistic reflection and partial covering. The NuSTAR spectra show a strong hard (> 15 keV) X-ray excess, while simultaneous soft X-ray coverage of one of the observations provided by XMM-Newton constrains the ionised absorption in the source. The pure reflection model requires a black hole of high spin (a > 0.92) viewed at a moderate inclination (i = 46 +1 −4 ). The pure partial covering model requires extreme parameters: the cut-off of the primary continuum is very low (22 +7 −5 keV) in one observation and the intrinsic X-ray emission must provide a large fraction (75%) of the bolometric luminosity. Allowing a hybrid model with both partial covering and reflection provides more reasonable absorption parameters and relaxes the constraints on reflection parameters. The fractional variability reduces around the iron K band and at high energies including the Compton hump, suggesting that the reflected emission is less variable than the continuum. |
| Databáze: |
OpenAIRE |
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