Astronomy Seminar Abstracts
Alice Allen (University of Maryland)
Receiving Credit for Research Software
Though computational methods are widely used in many disciplines, those who author these methods have not always received credit for their work. This presentation will cover recent changes in astronomy, and indeed, in many other disciplines, that include new journals, policy changes for existing journals, community resources, changes to infrastructure, and availability of new workflows that make recognizing the contributions of software authors easier. This talk will include steps coders can take to increase the probability of having their software cited correctly and steps researchers can take to improve their articles by including citations for the computational methods that enabled their research.
Griffin Hosseinzadeh (CfA)
2020: The Year of Twenty Thousand Transients
This year, for the first time, the IAU Transient Name Server is on track to surpass 20,000 astronomical transient reports. This presents both an enormous opportunity, in that previously “rare” classes of transients are now discovered routinely, but also a wake-up call that traditional techniques of classification and analysis are not cut out for the job. In this seminar, I will describe the landscape of transient astronomy in the coming decade: the aspects of stellar physics we can constrain using large samples of stellar explosions, as well as the data science methods our field must adopt in order to take full advantage of our observations. For example, initial samples of tens of core-collapse supernovae have provided surprising clues about pre-explosion eruptions in massive stars; orders-of-magnitude larger samples from the upcoming Legacy Survey of Space and Time will determine how commonly supernovae interact with circumstellar material from these eruptions. Likewise, Advanced LIGO and Virgo enabled the first direct observation of r-process nucleosynthesis in a binary neutron star merger; upgraded four- and five-detector networks will allow us to understand the diversity of these merger events. In both cases, modern cyberinfrastructure (e.g., real-time discovery alerts, robotic follow-up observations, robust image subtraction, machine-learning classification) will be key to maximizing the science return from these powerful discovery engines.
Kavitha Arur (Georga Tech)
Using the bispectrum to examine the geometry of the black hole corona
Quasi-periodic oscillations (QPOs), observed in the X-ray power spectrum of accreting black holes, are excellent probes of the physics governing the innermost regions of accretion disks. However, the process behind the origin of QPOs is still under debate. Sophisticated timing analysis techniques are thus required to break degeneracies between different models that produce identical power spectra. One such technique is a higher order time series analysis technique known as the bispectrum. I will present the results of the first systematic application of this novel bispectral analysis on QPOs and how this can be used to understand the geometry of the regions close to the black hole.
Emmanuel Fonseca (McGill University)
An Evolving View of FRB Astrophysics in the Era of CHIME
Fast radio bursts (FRBs) are intense, millisecond-duration signals of extragalactic origin; the physical nature of FRB sources is largely unknown and the subject of active debate. Current projections indicate that thousands of FRBs randomly occur across the sky per day, though most premier observatories are not naturally suited for real-time FRB detection. In this talk, I will discuss the autonomous FRB detection instrument built for the wide-field Canadian Hydrogen Intensity Mapping Experiment (CHIME) and its growing impact on FRB astrophysics. I will highlight recent science results from the CHIME/FRB project, and provide a view of the next steps being taken to further diversify its capabilities.