Open Access
Table 1.
Best-fitting parameters obtained in the spectral analysis of NICER and NuSTAR data during the three periods of observation.
Component | Parameter (unit) | Description | Values |
||
---|---|---|---|---|---|
Period 1 | Period 2 | Period 3 | |||
tbabs | NH(1022 cm−2) | Hydrogen column density | 0.17 ± 0.01 | 0.18 ± 0.01 | 0.19 ± 0.01 |
kerrbb | η | Inner-torque modification | 0 ( † ) | – | – |
a | BH spin | 0.992 ± 0.003 | – | – | |
i (deg) | Inclination | 75 ( † ) | – | – | |
MBH (M⊙) | BH mass | 4.6 ( † ) | – | – | |
Ṁ (1016 g s−1) | Mass accretion rate | 3.47 ± 0.04 | 3.59 ± 0.04 | 3.72 ± 0.05 | |
D (kpc) | Distance | 7.8 ( † ) | – | – | |
hd | hardening factor | 1.7 ( † ) | – | – | |
rflag | Self-irradiation | 1 ( † ) | – | – | |
sflag | Limb-darkening | 0 ( † ) | – | – | |
Norm | Normalisation | 1 ( † ) | – | – | |
expabs | EC (keV) | e-folding energy | 1.39 ± 0.02 | 1.41 ± 0.02 | 1.44 ± 0.02 |
powerlaw | Γ | Photon index | 1.93 ± 0.21 | – | – |
Norm (10−3) | Normalisation | 10.05 ± 4.67 | 4.74 ± 2.11 | 2.79 ± 1.29 | |
χ2/d.o.f. | 975.4/951 |
Notes. The expabs e-folding energy was obtained from an initial modelling using diskbb. Parameters marked with ( † )are kept frozen in the spectral analysis.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.