Constraining the Jet Properties of the New Transient X-ray Binary, Swift J1745-26, With the Submillimeter Array and James Clerk Maxwell Telescope

• Author / Creator

  Tetarenko, Alexandra Jean

• Accreting astrophysical sources are an important end-result of intricate stellar dynamics. A particularly puzzling aspect of this accretion process is the production and evolution of plasma outflows (known as jets). Although astrophysical jets have been studied for decades in accreting sources, the underlying physics that governs jet behaviour is still poorly understood. Since black hole X-ray binary (BHXRB) systems evolve on short timescales, the steady, compact relativistic plasma jet that is present at the onset of a BHXRB outburst serves as an important probe of jet physics and analogue for the universal process of jet production in other astrophysical systems. The detailed properties of BHXRB jets are encoded in the broadband spectral energy distribution (SED). However, we could only recently begin to fill in a large void in our broadband coverage, the mm/sub-mm regime. In this thesis, I discuss the results obtained from our observing campaign of the 2012 outburst of the new transient BHXRB, Swift J1745-26. These observations represent the first ever simultaneous radio and multiple-band mm/sub-mm observations of a BHXRB. The instruments used to obtain the data were the Karl G. Jansky Very Large Array (VLA), the Submillimeter Array (SMA) and the Submillimetre Common User Bolometer Array 2 detector on the James Clerk Maxwell Telescope (SCUBA-2 on the JCMT). With the combination of radio and mm/sub-mm data, I am able to directly measure the spectral indices in and between the radio and mm/sub-mm regimes as well as probe a relatively untested part of the jet spectrum (mm/sub-mm regime). I present these spectral measurements to determine whether the jet emission in the mm/sub-mm regime is consistent with typical jet models, where a single power-law can accurately describe the radio through sub-mm SED, as well as to constrain the origin of high mm/sub-mm fluxes that have been observed in the few BHXRBs in outburst. The spectral fitting process revealed that both the mm (230 GHz) and sub-mm (350 GHz) measurements are consistent with extrapolations from contemporaneous radio data (1-30 GHz) of a slightly inverted spectra (i.e., I measure higher flux density at higher frequencies). This indicates that even at higher mm/sub-mm frequencies a power-law can sufficiently describe the spectrum. Moreover, this suggests that the mechanism driving spectral inversion could be the same mechanism driving high mm/sub-mm fluxes in outbursting BHXRBs, rather then anomalous excess emission. Finally, I consider the effects of complex spectral features and flux variability at radio frequencies on our interpretation of the jet spectrum. Our analysis solidifies the importance of the mm/sub-mm regime in bridging the crucial gap between radio and IR frequencies in the jet spectrum, demonstrates the capacity of current mm/sub-mm instruments to address questions in this regime, and justifies the need to explore this regime in multiple sources.

• Subjects / Keywords

  • Mm astronomy
  • Synchrotron emission
  • Accretion
  • Spectral evolution
  • Stellar mass black hole
  • Radio astronomy
  • Relativistic outflow
  • Hard accretion state
  • Relativistic jet
  • X-ray binary
  • Sub-mm astronomy
  • X-ray binary outburst
  • Swift J1745-26
  • Spectral break
  • Supermassive black hole
  • Black holes
  • Black hole physics
  • Transient x-ray binary
  • High energy astrophysics
  • Black hole x-ray binary
  • Spectral energy distribution

• Graduation date

  Fall 2014

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3JD4PV4W

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.