The low-luminosity accretion disc wind of the black hole transient V4641 Sagittarii

Abstract

We present an optical spectroscopic study of the black hole X-ray transient V4641 Sgr (=SAX J1819.3-2525) covering the 1999, 2002 and 2004 outbursts. The spectra were taken over 22 different epochs during the low luminosity phases that follow the sharp and bright outburst peaks displayed by the system. The data reveal the frequent presence of wind-related features in H (Balmer) and He I emission lines in the form of P-Cygni profiles and strong emission lines with broad wings. The terminal velocity of the wind, as measured in the blue-shifted absorption (P-Cygni) components, is in the range of ~ 900-1600 km/s, while the broad emission line wings (so-called nebular phases) imply outflow velocities of up to ~3000 km/s. We show that, at least for several of the wind detections, the radio jet was active and the system was likely in the hard state. This, together with previous detections reported in the literature, shows that V4641 Sgr is the second source of this class, after V404 Cyg, where the presence of these cold wind outflows has been clearly established. We discuss the similar phenomenology observed in both systems as well as the possible nature of the outflow and its impact on the accretion process.

Accepted for publication in MNRAS

References in corpus (15)

• The magnetic nature of disk accretion onto black holes
• Studies of the Diffuse Interstellar Bands. III. HD 183143
• Black hole-like hysteresis and accretion states in neutron star low mass X-ray binaries
• Regulation of black-hole accretion by a disk wind during a violent outburst of V404 Cygni
• On the masses and evolutionary status of the black hole binary GX 339-4. A twin system of XTE J1550-564?
• Strong disc winds traced throughout outbursts in black-hole X-ray binaries
• Evidence for simultaneous jets and disk winds in luminous low-mass X-ray binaries
• Swift observations of V404 Cyg during the 2015 outburst: X-ray outflows from super-Eddington accretion
• The black hole binary V404 Cygni: an obscured AGN analogue
• A connection between accretion state and $\text{Fe K absorption}$ in an accreting neutron star: black hole-like soft state winds?
• On the Fe K absorption - accretion state connection in the Galactic center neutron star X-ray binary AX J1745.6-2901
• Flares, wind and nebulae: the 2015 December mini-outburst of V404 Cygni
• Photoionization instability of the Fe K absorbing plasma in the neutron star transient AX J1745.6-2901
• Outbursts of the intermediate-mass black hole HLX-1: a wind instability scenario
• The nova-like nebular optical spectrum of V404 Cygni at the beginning of the 2015 outburst decay

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