GMRT scientists Bhattacharya and Roys research published in Astrophysical Journal Letters.
Research by two scientists at the Giant Metrewave Radio Telescope (GMRT) near Pune has led to a new technique to help in precise identification and localisation of faint millisecond pulsars.
Millisecond pulsars are dense neutron stars with mass as huge as the sun. All this mass being compressed into a small,20-km radius makes millisecond pulsars (MSPs) very dense and compact. MSPs rotate a few hundred times a second thus the name millisecond pulsars and send out radio waves periodically directed towards the Earth,much like a lighthouse. The periodic motion has also made them natures best clock.
After initial localisation of a new pulsar,the usual method for precise identification of location needs a series of observations spanning months. The new method can help in precise and faster identification and localisation of pulsars to an accuracy 1,000 times more than initial localisation,according to Bhaswati Bhattacharya and Jayanta Roy of GMRT who have developed the technique. We developed a novel technique of gated imaging for millisecond pulsars. By taking the difference of these two images,precise identification and localisation is possible through a single set of observations to an accuracy 1,000 times more than initial localisation, said Bhattacharya,Radio Astro Physicist at GMRT.
Such immediate knowledge of accurate position accelerates follow-up study which can uncover their properties,like suitability for use in International Pulsar Timing array designed to detect gravitational wave signals in the universe. Such precise localisation facilitates the search for counterparts of pulsars,at optical and X-ray wavelengths, said Roy.
The development of this imaging technique and precise localisation of five newly discovered millisecond pulsars with GMRT have been published in March 10 issue of the Astrophysical Journal Letters.
Extension of these techniques to future large radio telescopes like the Square Kilometre Array (SKA) offers the only way for processing signals from such extended telescopes that could be spread over hundreds of kilometres,much larger than the GMRT, said Roy.