World News – UA – LIGO and Virgo announce new detections in updated gravitational wave catalog

Detection of gravitational waves has now become mainstream, just five years after the first detection in September 2015 With 50 detections of gravitational waves, scientists from IUCAA and other institutions have updated and published a new catalog

After several months of in-depth analyzes, an updated catalog of gravitational wave detections has been published by the scientific collaboration LIGO (Laser Interferometer Gravitational Wave Observatory) and the collaboration Virgo The catalog contains 39 new signals from black hole or neutron star collisions detected between April 1 and October 1, 2019, more than tripling the number of confirmed detections

This second updated catalog – Gravitational-Wave Transient Catalog 2 – and accompanying documents of gravitational wave (GW) events detected by the LIGO and Virgo gravitational wave detectors were to be published in The Astrophysical Journal , The Astrophysical Journal Letters, Physical Exam D and Physical Exam X October 29

The new set includes interesting systems and allows qualitatively new studies of astrophysical populations and fundamental physics “What is significant about this catalog, which lists the 50 binaries of black holes and neutron stars discovered so far by LIGO and Virgo is that it establishes quite firmly now that stellar mass black hole binaries and their collisions are relatively common in the universe. , and that a good part of them are heavier than what we thought before when our sample was mainly limited to black holes in our own galaxy, ”said Dr Sukanta Bose, president of the LIGO-India scientific collaboration (LISC), at The Indian Express

« This gives clues to the properties of the mother stars from which they first formed A large observational sample helps guard against bias The LIGO-India detector, which plans to join other detectors in the future in such observations, can help in this pursuit Almost 100 scientists – especially students and young researchers – have collaborated with their LIGO-Virgo partners to make these discoveries and enrich our understanding of some of the densest objects in the cosmos and where they come from. What’s just as fascinating is that we use them to test Einstein’s theory of gravity.If there is any deviation from his predictions, chances are good that observations like these reveal them first So far we have not found any evidence suggesting abnormalities, ”said Dr Bose

The sharp increase in the number of detections was made possible by significant improvements in the instruments compared to previous observation periods, said the senior scientist at the Interuniversity Center for Astronomy and Astrophysics These included increased laser power, improved mirrors, and the use of quantum compression technology Overall, these improvements resulted in an almost 60% improvement in signal detection range. The detectors were also able to operate continuously more often than in the past, with an improved duty cycle of approximately 75% compared to 60%

With all these new signals, we can begin to better understand the populations of black holes and neutron stars, scientists said.They also explained that the many signals in the updated catalog can be used to update tests Einstein’s theory of gravity more and better than before

This was done by comparing the data to theoretical predictions and limiting possible deviations The results of several signals were combined using new statistical methods to achieve the most stringent constraints to date on the properties of gravity in the strong and highly dynamic regime of black hole fusions With the new catalog, LIGO and Virgo were also able to directly study the properties of the remaining objects produced during the mergers: by measuring the vibrations of these objects, and by excluding any « echoes » after the main signals, LIGO and Virgo confirmed that the remains behaved as we would expect from black holes in Einstein’s theory

The results reported in the new catalog correspond only to the first six months of the third observation period of LIGO and Virgo The results of the remaining five months are currently being analyzed

In the meantime, the LIGO and Virgo instruments are being upgraded for the fourth round of observations, for which they will also be joined by the KAGRA detector in Japan. Other exciting discoveries are on the way. horizon, according to scientists

📣 The Indian Express is now on Telegram Click here to join our channel (@indianexpress) and stay up to date with the latest headlines

Black hole, Gravitational wave, Gravity, LIGO, Virgo interferometer