Stratified wind from a super-Eddington X-ray binary is slower than expected

Abstract

Accretion discs in strong gravity ubiquitously produce winds, seen as blueshifted absorption lines in the X-ray band of both stellar mass X-ray binaries (black holes and neutron stars), and supermassive black holes. Some of the most powerful winds (termed Eddington winds) are expected to arise from systems where radiation pressure is sufficient to unbind material from the inner disc ($L\gtrsim L_{\mathrm{Edd}}$). These winds should be extremely fast and carry a large amount of kinetic power, which, when associated with supermassive black holes, would make them a prime contender for the feedback mechanism linking the growth of those black holes with their host galaxies. Here we show the XRISM Resolve spectrum of the Galactic neutron star X-ray binary, GX 13+1, which reveals one of the densest winds ever seen in absorption lines. This Compton-thick wind significantly attenuates the flux, making it appear faint, although it is intrinsically more luminous than usual ($L\gtrsim L_{\mathrm{Edd}}$). However, the wind is extremely slow, more consistent with the predictions of thermal-radiative winds launched by X-ray irradiation of the outer disc, than with the expected Eddington wind driven by radiation pressure from the inner disc. This puts new constraints on the origin of winds from bright accretion flows in binaries, but also highlights the very different origin required for the ultrafast ($v\sim 0.3c$) winds seen in recent Resolve observations of a supermassive black hole at similarly high Eddington ratio.

author version of the accepted manuscript. see final published version at https://doi.org/10.1038/s41586-025-09495-w (Nature September 17 2025)

References in corpus (44)

• Powerful Outflows and Feedback from Active Galactic Nuclei
• Super-critically accreting stellar-mass black holes as ultraluminous X-ray sources
• Ubiquitous equatorial accretion disc winds in black hole soft states
• Global Structure of Three Distinct Accretion Flows and Outflows around Black Holes through Two-Dimensional Radiation-Magnetohydrodynamic Simulations
• The Chandra High Energy Transmission Grating: Design, Fabrication, Ground Calibration and Five Years in Flight
• Black hole feedback in the luminous quasar PDS 456
• Three-dimensional simulations of super-critical black hole accretion disks --- luminosities, photon trapping and variability
• The Accretion Disk Wind in the Black Hole GRO J1655-40
• Spectral changes during dipping in low-mass X-ray binaries due to highly-ionized absorbers
• The Physics of the 'Heartbeat' State of GRS 1915+105
• Revisiting a fundamental test of the disc instability model for X-ray binaries
• Accretion disc atmospheres and winds in low-mass X-ray binaries
• Systematic comparison of photoionised plasma codes with application to spectroscopic studies of AGN in X-rays
• Spectrum Synthesis Modeling of the X-ray Spectrum of GRO J1655-40 Taken During the 2005 Outburst
• The Accretion Disk Wind in the Black Hole GRS 1915+105
• Thermal Winds in Stellar Mass Black Hole and Neutron Star Binary Systems
• XMM-Newton observations of GX 13+1: correlation between photoionised absorption and broad line emission
• Discovery of narrow X-ray absorption features from the low-mass X-ray binary X 1254-690 with XMM-Newton
• An Obscured, Seyfert-2-like State of the Stellar-mass Black Hole GRS 1915+105 Caused by Failed Disk Winds
• Density diagnostics of ionized outflows in active galactic nuclei: X-ray and UV absorption lines from metastable levels in Be-like to C-like ions
• Structured ionized winds shooting out from a quasar at relativistic speeds
• An optically-thick disk wind in GRO J1655-40?
• Thermal Disk Winds in X-ray Binaries: Realistic Heating and Cooling Rates Give Rise to Slow, but Massive Outflows
• Multiphase AGN winds from X-ray irradiated disk atmospheres
• A Super-Eddington Compton-Thick Wind in GRO J1655-40?
• Chandra X-ray spectroscopy of a clear dip in GX 13+1
• Simultaneous radio and X-ray observations of the low-mass X-ray binary GX 13+1
• A NICER View of a Highly-Absorbed Flare in GRS 1915+105
• The thermal-radiative wind in low mass X-ray binary H 1743-322; Radiation hydrodynamic simulations
• The Disk Wind in the Neutron Star Low-mass X-Ray Binary GX 13+1
• Radiation-hydrodynamic simulations of thermally-driven disc winds in X-ray binaries: A direct comparison to GRO J1655-40
• What powers the wind from the black hole accretion disc in GRO J1655-40?
• Discovery of periodic dips in the light curve of GX 13+1: the X-ray orbital ephemeris of the source
• The thermal-radiative wind in low mass X-ray binary H 1743-322: II. iron line predictions from Monte Carlo radiation transfer
• The Case for Massive, Evolving Winds in Black Hole X-ray Binaries
• The current state of disk wind observations in BHLMXBs through X-ray absorption lines in the iron band
• Properties of the 24 Day Modulation in GX 13+1 from Near-Infrared and X-ray Observations
• New polarimetric study of the galactic X-ray burster GX 13+1
• Optimization of x-ray event screening using ground and in-orbit data for the Resolve instrument onboard the XRISM satellite
• Variable Doppler shifts of the thermal wind absorption lines in low-mass X-ray binaries
• A different view of wind in X-ray binaries: The Accretion Disc Corona source 2S 0921-630
• Application of the Thermal Wind Model to Absorption Features in the Black Hole X-ray Binary H 1743-322
• Impact of the disk magnetization on MHD disk wind signature
• On Synthetic Absorption Line Profiles of Thermally Driven Winds from Active Galactic Nuclei

Cited by in corpus (2)

• Accretion disc winds in X-ray binaries
• A highly ionised outflow in the X-ray binary 4U 1624-49 detected with XRISM