E-Paper
80 astronomers graviate to NCRA, Pune for future roadmap
Post the upgrade in NCRA’s GRMT, telescope has now become three times more sensitive and can be used in measuring low-frequency waves, a key factor behind NCRA being able to host the meet
Eighty international astronomers from 12 countries and 20 from India have registered to be a part of the annual meeting of International Pulsar Timing Array Collaboration, which will be held at the National Centre for Radio Astrophysics (NCRA) in Ganeshkhind.
The meet has been divided into two halves; one for students which began on June 10 and will conclude on June 17. The students component saw 55 students from 12 countries participate in the programme, while the second part of the meet will begin on June 17 and continue to June 21.
The current status of the quest for ultra-low frequency gravitational waves and the road map for the future, including both technical and scientific challenges, will be the main focus of the meeting.
Post the upgrade in NCRA’s the Giant Metrewave Radio Telescope (GRMT), the telescope has now become three times more sensitive and can be used in measuring low-frequency waves, a key factor behind NCRA being able to host the meet.
A recent discovery of gravitational waves, which are small wrinkles in space-time, came almost a hundred years after Albert Einstein’s prediction of these waves. This has opened a new window to study the universe. Like normal light, the gravitational waves also come in a wide range of wavelengths.
International Pulsar Timing Array collaboration (IPTA) is a collaboration of radio astronomers from a dozen countries around the globe. The IPTA uses more than 12 radio telescopes around the world with an aim to detect ultra-low frequency gravitational waves or nano-hertz gravitational waves.
“Gravitational waves are produced, when two massive compact astronomical objects such as black-holes orbit each other or merge. To measure the tiny wrinkles in space-time, we need extremely accurate clocks in the sky. Neutron stars formed after a massive star explodes provide such clocks. Some neutron stars emit radio emission in a pulsed manner. These pulsars can be used to form a giant celestial telescope to detect gravitational waves with a period of a billionth of a second,” said BC Joshi, senior scientist, NCRA, explaining in lay man’s terms.
Astronomers across the world have been using some of the largest radio telescopes for recording the pulsar signals from an array of pulsars, which forms a “Pulsar Timing Array (PTA)”, to detect which can identify ultra-low frequency waves (i.e, ultra-long wavelength gravitational waves).
Three PTA experiments in the US, Europe and in Australia have been in existence for last two decades in the quest of these long-wavelength gravitational waves, which are yet to be discovered, while an Indian experiment has been in operation for last three years using the upgraded GMRT and the Ooty Radio Telescope (ORT). All these experiments pool their data in a big international collaboration called International Pulsar Timing Array collaboration (IPTA).
A scientist on the condition of anonymity said, “These waves are wrinkles in space-time produced by two massive black holes, each revolving around the other. Such black holes, which weigh billion times more than our sun, are found in the centres of colliding galaxies. These waves affect radio pulses from 10 km size stars called radio pulsars by changing ever so slightly the period of radio pulsation of these stars. Measuring these periods to a precision of 10s of nano-seconds is likely to allow IPTA experiment to discover Gravitational Waves with a period of about a billionth of seconds,” said visiting professor, Mavia McLaughlin, Professor of Physics and Astronomy, West Virginia University, USA.
