India goes underground in hunt for neutri**s Deep beneath some granite hills in the south of India, the country's largest basic sciences project is in the works. DW's Murali Krishnan reports from Chennai on why the country's embarking on a subatomic megaproject. neutri**s are probably the strangest of all elementary particles - quick as light, unimaginable numbers of them race through space. They are a neutral, subatomic particle with a mass close to zero and a half-integral spin. They rarely interact with **rmal matter, which is perhaps why scientists around the world are eager to capture - and analyze - this process. "We have been part of many collaborations abroad," said the India-based Neutri** Observatory's outreach coordinator, physicist D. Indumathi. "Here, we have a fully Indian experiment where we have the chance to determine our own physics goals and ideas, our own experiments, our equipment." The I** will be housed in a 1.3 km-long tunnel (three quarters of a mile) that contains three caverns and a 50,000-ton iron calorimeter, which detects changes in heat. That neutri** detector will be the most massive in the world. Because neutri**s only weakly interact with other particles of matter, neutri** detectors must be very large in order to detect a significant number of neutri**s. "The tech**logy that we are building indige**usly is totally different from all the detectors that are built for neutri**s," says Anil Prabhakar, a professor in electrical engineering. "While a lot of other basic fundamental particles have been studied in large experiments, the neutri** has always been elusive." A slippery particle neutri**s come in three types, or "flavors": electron-neutri**, muon-neutri** and tau-neutri**. They oscillate among the three. Each neutri** flavor has a slightly different mass, although physicists do **t yet k**w exactly what those masses are. "These neutri**s do a three-level Jekyll and Hyde," says Indumathi. "They keep kind of oscillating into each other. So sometimes you see a neutri** as one type and as it goes along, it oscillates or transforms into a**ther type." One of the main aims of the experiment is to measure the mass of these neutri**s through these oscillations. The mass differences among flavors are believed to be the main factor affecting how neutri**s oscillate or morph as they pass through space, matter and Earth. Calculations suggest there must be around 40 billion of the "invisible" neutri**s in a cubic centimeter of the atmosphere. Despite their small size, the neutri** mass has far-reaching inferences - for example, implying that they played a decisive role in the formation of the universe. It potentially blurs the distinction between matter and antimatter, which might account for the apparent absence of antimatter. "One can address larger questions like matter and anti-matter asymmetry," says M V N Murthy, who is also associated with the project. "In order to understand all these things, neutri** is an important part which may lead to a better understanding of our universe." Neutri** race? Most advanced countries are already working vigorously in neutri** science with dedicated labs. These include the United States, Russia, France, Italy, China, Japan and South Korea. In March this year, China also an**unced the construction of a neutri** observatory in its Jiangmen province with similar goals. Like the I**, the Jiangmen underground neutri** observatory is expected to be completed by 2020. Work has already begun. With so many countries studying the properties of neutri** it would almost seem as if there is a race among growing eco**mies But Indumathi feels differently. "I think there are neutri** physicists everywhere on earth. Some are underground, some are on the surface of the earth, and some are at the South Pole. I think there is ** limit to neutri** physicists in choosing sites," she says. This project in India involves nearly 26 scientific institutions and about 100 scientists drawn from the country, a collaboration which is expected to grow further in the coming years. Apart from the scientific aims, it is the largest basic sciences project ever considered in India. The scientific community believes the ambitious project could open up new vistas in the fields of astro**my and astrophysics, communication and even in medical imaging, through the detector spin-offs. While environmental impact concerns have delayed the project, the scientists involved expect research results within 15 years.
08-19-2015, 11:48 PM
India goes underground in hunt for neutri**s
Deep beneath some granite hills in the south of India, the country's largest basic sciences project is in the works. DW's Murali Krishnan reports from Chennai on why the country's embarking on a subatomic megaproject. neutri**s are probably the strangest of all elementary particles - quick as light, unimaginable numbers of them race through space. They are a neutral, subatomic particle with a mass close to zero and a half-integral spin. They rarely interact with **rmal matter, which is perhaps why scientists around the world are eager to capture - and analyze - this process. "We have been part of many collaborations abroad," said the India-based Neutri** Observatory's outreach coordinator, physicist D. Indumathi. "Here, we have a fully Indian experiment where we have the chance to determine our own physics goals and ideas, our own experiments, our equipment." The I** will be housed in a 1.3 km-long tunnel (three quarters of a mile) that contains three caverns and a 50,000-ton iron calorimeter, which detects changes in heat. That neutri** detector will be the most massive in the world. Because neutri**s only weakly interact with other particles of matter, neutri** detectors must be very large in order to detect a significant number of neutri**s. "The tech**logy that we are building indige**usly is totally different from all the detectors that are built for neutri**s," says Anil Prabhakar, a professor in electrical engineering. "While a lot of other basic fundamental particles have been studied in large experiments, the neutri** has always been elusive." A slippery particle neutri**s come in three types, or "flavors": electron-neutri**, muon-neutri** and tau-neutri**. They oscillate among the three. Each neutri** flavor has a slightly different mass, although physicists do **t yet k**w exactly what those masses are. "These neutri**s do a three-level Jekyll and Hyde," says Indumathi. "They keep kind of oscillating into each other. So sometimes you see a neutri** as one type and as it goes along, it oscillates or transforms into a**ther type." One of the main aims of the experiment is to measure the mass of these neutri**s through these oscillations. The mass differences among flavors are believed to be the main factor affecting how neutri**s oscillate or morph as they pass through space, matter and Earth. Calculations suggest there must be around 40 billion of the "invisible" neutri**s in a cubic centimeter of the atmosphere. Despite their small size, the neutri** mass has far-reaching inferences - for example, implying that they played a decisive role in the formation of the universe. It potentially blurs the distinction between matter and antimatter, which might account for the apparent absence of antimatter. "One can address larger questions like matter and anti-matter asymmetry," says M V N Murthy, who is also associated with the project. "In order to understand all these things, neutri** is an important part which may lead to a better understanding of our universe." Neutri** race? Most advanced countries are already working vigorously in neutri** science with dedicated labs. These include the United States, Russia, France, Italy, China, Japan and South Korea. In March this year, China also an**unced the construction of a neutri** observatory in its Jiangmen province with similar goals. Like the I**, the Jiangmen underground neutri** observatory is expected to be completed by 2020. Work has already begun. With so many countries studying the properties of neutri** it would almost seem as if there is a race among growing eco**mies But Indumathi feels differently. "I think there are neutri** physicists everywhere on earth. Some are underground, some are on the surface of the earth, and some are at the South Pole. I think there is ** limit to neutri** physicists in choosing sites," she says. This project in India involves nearly 26 scientific institutions and about 100 scientists drawn from the country, a collaboration which is expected to grow further in the coming years. Apart from the scientific aims, it is the largest basic sciences project ever considered in India. The scientific community believes the ambitious project could open up new vistas in the fields of astro**my and astrophysics, communication and even in medical imaging, through the detector spin-offs. While environmental impact concerns have delayed the project, the scientists involved expect research results within 15 years.
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