Evidence for simultaneous jets and disk winds in luminous low-mass X-ray binaries

TL;DR

This study provides evidence that in luminous low-mass X-ray binaries, jets and disk winds can occur simultaneously, challenging the previous notion that they are mutually exclusive and mainly occur in different spectral states.

Contribution

The paper demonstrates that jets and disk winds can coexist in luminous LMXBs, using archival data and literature to show simultaneous presence in specific spectral states.

Findings

Jets and disk winds occur in the same location on the X-ray color-color diagram.

Simultaneous jets and winds are observed in multiple luminous LMXBs.

This behavior is more common in high-luminosity states than previously thought.

Abstract

Recent work on jets and disk winds in low-mass X-ray binaries (LMXBs) suggests that they are to a large extent mutually exclusive, with jets observed in spectrally hard states and disk winds observed in spectrally soft states. In this paper we use existing literature on jets and disk winds in the luminous neutron star (NS) LMXB GX 13+1, in combination with archival Rossi X-ray Timing Explorer data, to show that this source is likely able to produce jets and disk winds simultaneously. We find that jets and disk winds occur in the same location on the source's track in its X-ray color-color diagram. A further study of literature on other luminous LMXBs reveals that this behavior is more common, with indications for simultaneous jets and disk winds in the black hole LMXBs V404 Cyg and GRS 1915+105 and the NS LMXBs Sco X-1 and Cir X-1. For the three sources for which we have the necessary spectral information, we find that the simultaneous jets/winds all occur in their spectrally hardest states. Our findings indicate that in LMXBs with luminosities above a few tens of percent of the Eddington luminosity, jets and disk winds are not mutually exclusive, and that the presence of disk winds does not necessarily result in jet suppression.