Vishnu Balakrishnan (Max Planck Institute for Radio Astronomy (MPIfR))

Vishnu Balakrishnan Colloquium: Advanced Techniques to Search for Relativistic Binary Pulsars

Marsfield lecture theatre

Abstract

Relativistic binary pulsar systems, such as double neutron star and neutron star-white dwarf binaries are currently some of the best tools available to test Einstein’s theory of general relativity and the alternative theories of gravity in the strong gravitational field regime. A radio pulsar with a black hole companion would be a model system for such tests because of the immense orbital velocities and gravitational potentials present. However, finding such systems is difficult because of their apparent spin period changes due to the Doppler effect. Acceleration searches are commonly used to take this into account but still have limited sensitivity in the case of short orbital period binaries. In this talk, I will describe a new search technique using the stochastic template-bank algorithm that can search coherently for circular binary orbits of any orbital period, thereby increasing our sensitivity to the potential pulsar-black hole binaries in our galaxy. I will also present some early results using this technique on the most sensitive blind pulsar survey to date, High Time Resolution Universe Low Latitude (HTRU-S Lowlat) survey which was observed using the Parkes Radio Telescope.