LIGO-India is a collaborative project proposed by the LIGO Laboratory and the Indian Initiative in Gravitational Observations (IndIGO) to create a world-class gravitational-wave detector in India. The LIGO Laboratory, with permission from the U.S. National Science Foundation and Advanced LIGO partners from the U.K, Germany and Australia, has offered to provide all of the designs and hardware for one of the two planned Hanford Advanced LIGO detectors to be installed, commissioned, and operated by an Indian team of scientists in a facility to be built in and by India.
The motivations behind this project are clear and compelling. The expansion of worldwide activities in gravitational-wave detection to produce an effective global network has been a goal of LIGO for many years. In 2010, a developmental roadmap issued by the Gravitational Wave International Committee (GWIC) recommended that an expansion of the global array of interferometric detectors be pursued as a highest priority. Such a network would afford astrophysicists with more robust search capabilities and higher scientific yields. The current agreement between the LIGO Scientific Collaboration and the Virgo collaboration links three comparable sensitivity detectors and forms the core of this international network. Yet further detectors are extremely important. A fourth site not in the plane formed by the present three and distant from them all greatly improves source localization ability. Studies indicate that the localization of sources by a network that includes a detector in India would provide significant improvements. Improvements in localization averages are predicted to be approximately an order of magnitude, with substantially larger improvements in certain regions of the sky.
The project requires the support and agreement of both governments in addition to the the LIGO Laboratory and IndiGO. The project was discussed at a Joint Commission meeting between India and the US in June 2012. In parallel, the proposal was evaluated by LIGO's funding agency, the NSF. As the basis of the LIGO-India project entails the transfer of one of LIGO's detectors to India, the plan would affect work and scheduling on the Advanced LIGO upgrades already underway. In August 2012, the U.S. National Science Board approved the LIGO Laboratory's request to modify the scope of Advanced LIGO by not installing the Hanford "H2" interferometer, and to prepare it instead for storage in anticipation of sending it to LIGO-India. In India, the project has been presented to the Department of Atomic Energy and the Department of Science and Technology for approval and funding. Final approval is pending.