Pulsar in binary system seen with UTMOST

31/05/15 PSR J1141-6545 has been seen orbiting its white dwarf companion every 4.8 hours using the UTMOST telescope.

The system is a binary radio pulsar that consists of a neutron star and white dwarf in an eccentric orbit (e=0.2) that exhibits a wide range of relativistic phenomena. The binary completes five orbits per day and has a large rate of advance of periastron(5.33o/yr) explained by Einstein’s General Theory of Relativity.

Data were taken by PhD student Vivek V Krishnan on the night of May 30th 2015. The error bars are too small to see in the plot, which shows the change in the pulsar’s frequency as a function of time, over a little more than a complete orbit.

Screenshot - 310515 - 13:39:35
A plot of the arrival times of the pulses from the neutron star in the binary system, versus time, showing a characteristic nearly sinusoidal variation as stars orbit each other.
Data taken with UTMOST show the pulse from the neutron star (bottom panel) as well as its characteristics as a function of time and frequency (middle panels). The vertically aligned pulse as a function of phase (middle right panel) indicates an excellent fit for the orbit has been achieved.

Image credits: Vivek V Krishnan and Matthew Bailes.