Chris Mann

The Subaru Pathfinder Instrument for Discovering Exoplanets and Retrieving Spectra (SPIDERS) is an experimental setup testing the feasibility of adding some new technologies and procedures to a telescope's repertoire. Sitting behind an AO system to correct for atmospheric turbulence, SPIDERS employs a coronograph and closed-loop self-coherent camera to achieve even better wavefront control and extremely high-contrast images. My involvement is on the image post-processing side employing a technique called Coherent Differential Imaging (CDI). CDI enhances the already formidable contrast, allowing for the detection of faint exoplanets near their bright hosts. SPIDERS will be installed on the Subaru telescope in Hawaii to provide on-sky verification of its capabilities.

The Transiting Exoplanet Survey Satellite (TESS) was designed to find and characterize exoplanets around nearby and bright stars. It has done its job very well, discovering thousands of new exoplanet candidates! Impressive as this feat is, an equally expansive effort must be undertaken to validate each and every one. The TESS Follow-up Observing Program (TFOP) organizes this multi-disciplinary, multi-national, and multi-faceted endeavour into an efficient and effective force for verifying these candidates. Even so, a huge amount of work involved. Typically, small telescopes are used to check for false-positive detections, and refine the candidates' physical and orbital properties. Particular dedication is required for candidates that exibit only a single transit in the TESS data, severely limiting our ability to constrain the nature of system. These longer-period targets are tackled by the TESS Single Transit Planet Candidate (TSTPC) working group. I have been closely involved with TFOP and the TSTPC groups throughout my Ph.D. studies and beyond, and I have a particular interest in catching re-transits of targets with very uncertain periods, locking in their orbital characteristics and enabling them for additional study.

The Near-Earth Object Surveillance Satellite (NEOSSat) is a small Canadian cube-sat jointly operated by the Canadian Space Agency and Defence Research and Development Canada. As its name implies, NEOSSat was designed to improve our understanding of local space, observing near-Earth asteroids and artificial satellites. In recent years, NEOSSat has been opened to Canadian astronomers for general astronomical observations.

I have been leveraging NEOSSat's space-based vantage point to provide long-baseline exoplanet transit coverage for targets that are challenging to observe from the ground. NEOSSat's ability to stare continuously for long durations is extremely valuable for hunting uncertain planetary periods.

The Dragonfly Telephoto Array (or simply, "Dragonfly") is a composite refractor telescope built by combining 48 individual telephoto lenses and imagers to improve the sensitivity. Designed to capture ultra-faint structures like diffuse galaxies and stellar streams, Dragonfly would operate during dark skies when the moon was below the horizon.

In collaboration with the Dragonfly team, I adapted the observing routines and developed new scheduling and reduction procedures to enable the instrument for exoplanet transit observations. I employed Dragonfly to make semi-automatic observations for the TESS Follow-up Observing Program, providing physical and orbital constraints on exoplanet candidates.

IMBHs are somewhat of an enigma in modern astronomy. Small black holes on the scale of a few solar masses or huge ones of millions or billions of solar masses are well documented. The largely missing objects of a few thousand solar masses represent a break in the presumed chain of growth of these objects. One environment where these objects are potentially thought to reside are the dense cores of globular clusters. By carefully measuring the motions of stars in the cluster 47 Tucanae, I developed a multi-component model of stars and stellar remnants that reproduces the observed velocities. We determined that plausible dark populations of small black holes and neutron stars could adequately reproduce the data in the core, without the need for invoking a IMBH.