It is over a decade since Indian scientists began formal work on one of the country’s biggest research projects in basic sciences: the India-based Neutrino Observatory or INO. Proposed to be set up in a cavern under a 1,300 metre tall peak in the Bodi West Hills in Theni district, the observatory has run into unexpected delays. But finally, there seems to be light at the end of the tunnel with researchers deciding to begin operations from a rented building in Madurai.
Speaking to The Hindu over phone, INO spokesperson Naba K. Mondal, also a physicist with the Tata Institute of Fundamental Research (TIFR), a nodal agency for the implementation of the project, said that it has been proposed to rent a building near Madurai Kamaraj University at Nagamalai Pudukottai until the proposed National Centre for High Energy Physics (NCHEP) here begins taking shape. “We will start operations very soon,” he said on a positive note.
Mr. Mondal said that works relating to surveying the area, clearance of jungle and erection of fencing around the INO site in Theni as well as the NCHEP site here were in the final stages. The State Highways Department had been asked to lay the approach roads. “They will start making the roads soon in order to facilitate movement of construction materials to the site,” he said. The Union Ministry of Environment and Forests (MoEF) had accorded clearance to the site in October 2010.
The project, estimated to cost around Rs.1,350 crore, was being funded jointly by the Department of Atomic Energy and Department of Science and Technology. It was originally planned to be established in the Nilgiri hills. But the MoEF refused clearance on the ground that the location might disturb the natural habitat of wild animals. It was then that the Neutrino Collaboration Group (NCG), an association of different scientific institutions, shifted the site to West Bodi Hills.
The observatory will be located in a cavern at the bottom of peak number 1589 situated in a reserve forest area. The cavern could be accessed through a 2,100 metre long and 7.5 metre wide tunnel to be dug at the bottom of the peak. About 26 hectares of revenue land have been acquired near the entrance to the proposed tunnel for the purpose of establishing surface facilities required for operating the observatory.
What are neutrinos? According to scientists involved in the project, neutrinos are elementary particles, like electrons, but not part of atoms. They are available in abundance in the universe. The human body also emits neutrinos. These particles were created in large numbers during the Big Bang that led to the creation of the universe. They also continue to get created when the cosmic rays interact with the atmosphere. Scores of neutrinos pass through the human body without causing any harm because they hardly interact with matter.
Their non-interacting nature makes them difficult to detect especially on the earth’s surface, which is overwhelmed with cosmic ray events. Therefore, it had been decided to establish the observatory under a peak to shield it from cosmic ray particles. A magnetised Iron Calorimeter (ICAL) detector weighing about 50,000 tonnes would be installed in the INO cavern laboratory to study the neutrinos in detail as even their mass had not yet been measured accurately by the scientific community.
Though the NCG had managed to obtain government clearances required for the project as well as able to quell most of the apprehensions of the locals through a series of meetings with them, the project was nevertheless facing criticism from environmental activists like V.T. Padmanabhan who had been claiming that the INO would have an adverse biological, geological and radiological impact. However, the NCG has denied the apprehensions raised by him.
Mr. Padmanabhan has claimed that there was a plan to beam neutrinos manufactured at Fermilab, a high energy physics laboratory in the United States to the proposed INO in Theni for the purpose of studying the changes that occur during the journey. However, the NCG has denied this claim. It says that the primary goal of the INO lab was to study naturally occurring neutrinos in the atmosphere. There was no possibility of studying neutrino beams for the next 10 to 20 years.
Even assuming that such a study of neutrino beams was carried out, it would not be harmful in any way as “a person standing in front of the beam continuously for about 100 years would find that only one neutrino had interacted with his body in a lifetime, while billions of neutrinos would have passed harmlessly every second,” the NCG has claimed.