Gravitational wave detectors rigorously probe the universe to reveal phenomena that have remained mysteries. But these instruments are highly sensitive. Scientists say that
even earthquakes of magnitude four on the Richter scale could interfere with the detector’s functions.
Last month, Nikhil Mukund of IUCAA in collaboration with institutes in Italy, the United States, and the United Kingdom reported a technique for dealing with earthquakes. They took archival data on seismic events and, using machine learning algorithms, devised ways to predict the impact of earthquakes and take appropriate measures. Using algorithms, they can now switch control configurations, such that the interferometers remain locked even under excessive ground motions.
Though measures have been taken to isolate these detectors from large-magnitude earthquakes, small magnitude tremors still posed a problem. Last fortnight, Nikhil Mukund and Sanjith Mitra from the IUCAA, Pune and Surendra Nadh Somala from the IIT Hyderabad collaborated with the Laser Interferometer GravitationalWave Observatory in Livingston, USA to develop a model to understand the effects of these small-magnitude earthquakes.
They found that the major source for such earthquakes is the hydromechanical drilling carried out by oil industries in the surrounding region. Such drilling exposes the underlying fault lines to high pressure, resulting in tremors. Though these seismic events cannot cause any structural damage, they affect gravitational wave detectors. However, the algorithms created to deal with large earthquakes cannot deal with small tremors caused by nearby industries. The team stresses the need to curb such activities by oil industries in the vicinity of the detectors. They also call for highly sensitive seismometers that can detect low magnitude tremors precisely and rapidly.
With many countries aiming to build both above ground and underground detectors, such contributions make Indian scientists leaders in this area of research, even before gravitational detectors are built here.
DOI: 10.1088/1361-6382/ab0d2c 2
DOI: 10.1088/1361-6382/ab1360
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