Wednesday Colloquia

LIGO-India Project

by Dr. Sendhil Raja (Advanced Lasers & Optics Division, RRCAT, Indore)

Wednesday, July 18, 2018 from to (Asia/Kolkata)
at Lecture Theatre ( AG-66 )
TIFR
Description
Gravitational waves can be detected using many techniques such as resonant bars, resonant spheres, satellite position monitoring, interferometric detection, pulsar timing, etc. Of these the interferometer detector is most promising due to it broadband sensitivity and scalability. The Michelson interferometer is a 'natural' detector of gravitational waves because of the differential changes in the two orthogonal arms induced by the quadruple field of the gravitational waves. A passing gravitational wave will modulate the distance between two inertial test masses. This change in distance is very very small, even the strongest gravitational waves from known astrophysical sources will produce a strain of 10^-22. Interferometer detectors with arm length of kms and working at the shot noise limit are required to be able to detect such small strains. Two such km class detectors are the Laser Interferometer Gravitational-wave Observatory (LIGO) detectors in the United States, located in Livingston, Louisiana, and Hanford, Washington, separated by about three thousand kms. A third detector labeled LIGO-India is being setup in India under a joint collaboration between NSF and DAE-DST.

The talk will provide an overview of the LIGO-India Project, its current status and progress. The talk will also cover the various activities being pursued at RRCAT for developing ultra-precise optics and narrow line width lasers for both the Advanced-LIGO detector and the next generation of Gravitational Wave detectors. The talk will present the challenges in fabrication of optics for future upgrades to the Advanced-LIGO detectors and the next generation of Gravitational Wave detectors.