Resolved, expanding jets in the Galactic black hole candidate XTE J1908+094

• Author(s) / Creator(s)

  • Rushton, Anthony P.
  • Miller-Jones, James C. A.
  • Curran, P. A.
  • Sivakoff, Gregory Robert
  • Rupen, Michael P.
  • Paragi, Zsolt
  • Spencer, Ralph E.
  • Yang, Jinhyuk
  • Altamirano, Diego
  • Belloni, Thomaso M.
  • Fender, Rob P.
  • Krimm, H. A.
  • Maitra, D.
  • Migliari, Simone
  • Russell, D. M.
  • Russell, Thomas D.
  • Soria, Roberto
  • Tudose, Valeriu

• Black hole X-ray binaries undergo occasional outbursts caused by changing inner accretion flows. Here we report high angular resolution radio observations of the 2013 outburst of the black hole candidate X-ray binary system XTE J1908+094, using data from the Very Long Baseline Array and European VLBI Network. We show that following a hard-to-soft state transition, we detect moving jet knots that appear asymmetric in morphology and brightness, and expand to become laterally resolved as they move away from the core, along an axis aligned approximately −11° east of north. We initially see only the southern component, whose evolution gives rise to a 15-mJy radio flare and generates the observed radio polarization. This fades and becomes resolved out after 4 days, after which a second component appears to the north, moving in the opposite direction. From the timing of the appearance of the knots relative to the X-ray state transition, a 90° swing of the inferred magnetic field orientation, the asymmetric appearance of the knots, their complex and evolving morphology, and their low speeds, we interpret the knots as working surfaces where the jets impact the surrounding medium. This would imply a substantially denser environment surrounding XTE J1908+094 than has been inferred to exist around the microquasar sources GRS 1915+105 and GRO J1655−40.

• Date created

  2017-01-01

• Subjects / Keywords

  • X-Rays: Binaries
  • Ism: Jets And Outflows
  • Radio Continuum: Stars
  • Stars: Individual: Xte J1908+094

• Type of Item

  Article (Published)

• DOI

  https://doi.org/10.7939/r3-1paq-kj76

• License

  This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2017 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.