Ben Pennell   (Canada)

bepennell @ mpia.de

Modelling and understanding the incidence of compact binaries in our Galaxy

In this era of multi-epoch and full-sky surveys, namely the Gaia mission, it is possible to make powerful inferences on statistical models of stellar populations. In my work, I will develop methods to use the breadth of astrometric data available to better constrain models of populations of objects in our Galaxy, with an aim to deduce the physics behind these systems.

As an example, most stars appear in binaries, and many stars will have non-luminous companions (planets, black holes, etc.). With Gaia, one gets many measurements of a star's motion across the sky. Since a single star should move in a (nearly) straight line, deviating from this straight line could indicate the star is orbiting an unseen companion. With a large enough ensemble of statistics of this nature, one can place powerful constraints on the underlying population of binaries and the objects that they're made of. The ultimate goal is to place constraints on the populations of black holes and neutron stars.

Outside of this research, I also take an interest in the history and philosophy of science.

Supervisor:    Hans-Walter Rix  (MPIA)