Finding New Compact Binaries Using High-precision Photometry
Abstract
The mass and orbital distribution of existing black holes and neutron stars in binaries can have important implications on binary massive stellar evolution, shedding light on gravitational wave astronomy. However, the detected number of compact objects in binaries is orders of magnitude less than those predicted. Traditional ways to look for black holes (e.g., in X-ray binaries) are known to be biased against wide binaries, and possibly mass-gap black holes. Recent studies employing radial velocity searches and optical photometry have started to reveal new systems less probed before. In recent years, exoplanet-search satellites such as Transiting Exoplanet Survey Satellite (TESS) have opened an era of high-precision photometry of a large number of stars. In this talk, the speaker will demonstrate that TESS photometric data do contain periodicity signals of known redback pulsar-like systems, by observing the orbital period-modulated flux variation from the stellar companion. The speaker and his research group went on to identify a group of potential pulsar binaries within Fermi gamma-ray source locations. They have also made an estimate of searchable black hole binaries (~a few) in the field of Kepler. Identifying orbital period-modulated flux variation due to compact objects is a non-trivial task, and he will report the ongoing progress. Upcoming and planned exoplanet-search satellites such as PLATO, Roman, Earth 2.0 guarantee the discovery space in such a hunt for compact objects. In the end of the talk, he will introduce the CSST Big Bay Area Science Center and the upcoming funding opportunities.
About the speaker
Prof. Thomas Tam Pak Hin received his BSc from the University of Hong Kong in 2002 and PhD from Heidelberg University in 2008. He then moved to the National Tsing Hua University in Taiwan as a Postdoctoral Fellow and joined the Sun Yat-Sen University in 2014. He is now an Associate Professor in the Sun Yat-Sen University.
Prof. Tam is a high-energy astrophysicist and his research focuses on the studies of gamma-ray binaries, compact binaries, and gamma-ray bursts. His major academic accomplishments include establishing the mysterious GeV flares from PSR B1259-63 and a new high-energy component in gamma-ray bursts. Both phenomena remain unresolved. Over the years, he has been a member of several international collaborations of operating high-energy experiments: H.E.S.S., CTA, LHAASO. He has been promoting high-energy astrophysics in East Asia within the Fermi Asian Network and beyond.
For Attendees' Attention:
This talk will be held online via Zoom. To join the talk online, please join the Zoom meeting at https://hkust.zoom.us/j/96462318783.
