Broadband X-ray study of the galactic black hole binary 4U 1630-47 with Suzaku

Abstract

We present the results from our Suzaku observations of the Galactic black hole binary 4U 1630-47. 4U 1630-47 was observed in the very high state (VHS) during the 2012 September-October outburst. The inner disk appears slightly truncated by comparison with a previous high/soft state (HSS) of this source, even by taking into account energetic coupling between the disk and corona. The spectra do not show the Doppler-shifted emission lines indicating baryonic jets that were seen four days previously in an XMM-Newton observation, despite the source being in a similar state. There are no significant absorption lines from highly ionized iron ions. We also observed 4U 1630-47 in the HSS simultaneously with Suzaku and NuSTAR in an early epoch of the 2015 outburst. All Suzaku spectra in the HSS show variable iron-K absorption line features. We find that the ionization state of the disk wind rapidly increased when the continuum showed significant spectral hardening. This behavior is consistent with that expected from a thermally driven wind.

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