The Definitive All-Sky Observational Study Of Accretion Disc Physics In Galactic Black Hole X-ray Binaries

  • Author / Creator
    Tetarenko, Bailey E
  • Stellar mass black holes (BHs) accreting in binary systems provide valuable insight into how binary systems evolve and how mass is transferred via accretion. Although in recent years a canonical picture of the outburst evolution in black hole X-ray binaries (BHXRBs) has emerged, these systems actually exhibit a wide range of unorthodox behaviour as well. Using today's more sensitive all-sky X-ray instruments, which have made an in-depth exploration of the X-ray Universe possible, we have the ability to classify the range of behaviours exhibited by these accreting BHs. Taking advantage of these resources, we have established a comprehensive database of BH (and BH candidate) XRB activity over the last 18 years as revealed by the Swift Burst Alert Telescope (BAT), Monitor of All-Sky X-ray Image (MAXI) telescope, Rossi X-ray Timing Explorer (RXTE), and the INTErnational Gamma-ray Astrophysics Laboratory (INTEGRAL). As a result we have detected 90 outbursts occurring in 43 transient BHXRBs, tracked the long-term behaviour of 9 persistent BHXRBs, and estimate that the current suite of instruments in space can detect ~ 6-12 transient outbursts every year, more than a factor of two larger than with RXTE alone. Perhaps our most noteworthy result comes in the discovery that, despite the prevailing opinion, the outbursts undergone by BHXRBs that do not complete the canonical pattern (i.e., those that fail to transition to the soft accretion states) make up ~ 50% of all outbursts occurring in transient BHXRBs in the past 18 years. Interestingly enough, we find that these "failed" outbursts are not just limited to the transient systems but are also exhibited by a fair number of persistently accreting systems in the form of long continuous periods spent in the hard state. This "failed" behaviour being neither a rare nor recent phenomena, challenges the standard paradigm for accretion behaviour in both transient and persistent BHXRBs. The questions that remain are, "what ramifications do the larger number of these "failed" outbursts have on the mass-transfer history of the Galactic BHXRB population" and "what observational parameters best probe the degree to which this behaviour impacts the population as a whole". In this thesis we present the detailed findings of our database making use of X-ray hardness, luminosity, disc fraction, and mass-transfer rate to probe canonical and anomalous outburst behaviour exhibited by BHXRBs, its impact on the physical observables of individual systems alone, and the universal properties of the population as a whole. We show that enumerating the frequency at which outbursts occur and quantitatively classifying the wide range of behaviour exhibited during outburst is critical to furthering our understanding of the physical mechanisms driving mass-accretion in BHXRBs and a key step toward filling in the many gaps in our knowledge of how BHXRBs form, accrete, and evolve.

  • Subjects / Keywords
  • Graduation date
    Fall 2014
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • 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.
  • Language
  • Institution
    University of Alberta
  • Degree level
  • Department
  • Supervisor / co-supervisor and their department(s)
  • Examining committee members and their departments
    • Sydora, Richard (Physics)
    • Ivanova, Natasha (Physics)
    • Heinke, Craig (Physics)