36th Annual Report (2023-24)

27 custom built sensors and actuators are also developed. The horizontal sensors use a Folded Pendulum Sensor (FPS) design and the vertical sensors use a Geometric Anti-Spring (GAS) design. These sensors have been fabricated and are being tested at present and show promising results. Displacement sensors (OSEMs) which are used in LIGO detectors have been adapted for use in these seismic sensors. Work is ongoing to improve the signal to noise ratio of these sensors in the 0.1-10 Hz frequency band where these sensors suffer fromhigh 1/f noise. Exploration of isolator design, sensing and actuation in this integrated facility forms one of the training modules for LIGO-India commissioning and operation. LIGO-India ¬ The LIGO-India project received approval by the Union Cabinet last year which created a lot of excitement in the country. The project is funded by the Department of Atomic Energy (DAE) and the Department of Science and Technology (DST), Government of India, with a Memorandum of Understanding (MoU) with the National Science Foundation (NSF), USA, along with several national and international research and academic institutions. IUCAA is one of the four lead institutions executing the project. IUCAA is responsible for computing facilities and human resource development for the project. IUCAA is also the key science stakeholder for the project and interface to the national and international scientific communities. It is playing a major role in growing the community. The observatory aims to start science operations by 2030 Figure showing a CAD rendering of the Roberts Linkage seismic isolator, Folded Pendulum Seismometer and the Low Frequency Geophone designs. There are many more instrumentation modules and experiments are being developed at IUCAA for human resource development, which also have strong research potential, which can mature in the next few years. This program is however evolving to cater to the needs of the LIGO- India project.