Four solar neutrino experiments are currently taking data. Other frequently-discussed weak interaction solutions to the solar neutrino problem are also not expected to change significantly the line profile. 1 The characteristic modulation of the 7Be line shape that would be caused by either vacuum neutrino oscillations or by matter-enhanced (MSW) neutrino oscillations is shown to be small. The energy profile of the 7Be neutrino line should be taken into account in calculations of vacuum neutrino oscillations and of the absorption cross section for 7 Be solar neutrinos incident on 7 Li nuclei. The effective temperature of the high-energy exponential tail is 15 × 106 K.
The line shape is asymmetric: on the low-energy side, the line shape is Gaussian with a half-width at half-maximum of 0.6 keV and on the high-energy side, the line shape is exponential with a half-width at halfmaximum of 1.1 keV. The energy profile of the 7Be line is derived analytically and is evaluated numerically. Therefore, a measurement of the energy shift is a measurement of the central temperature distribution of the sun. The energy shift is approximately equal to the average temperature of the solar core, computed by integrating the temperature over the solar interior with a weighting factor equal to the locally-produced 7Be neutrino emission. This energy shift is calculated to be 1.29 keV (to an accuracy of a few percent) for the dominant ground-state to ground-state transition. The success of these scientists is truly something in which Canadians can take great pride.A precise test of the theory of stellar evolution can be performed by measuring the average difference in energy between the neutrino line produced by 7Be electron capture in the solar interior and the corresponding neutrino line produced in a terrestrial laboratory. Maxime Bernier, Minister of Industry and Minister responsible for NSERC, added, "The world-class facilities at SNO, coupled with a community of top-notch physicists have made Canada a global leader in the search for answers to some of the deepest mysteries of the universe. "I was fortunate to have joined the collaboration at a time when contributions from TRIUMF in its infrastructure role supporting the Canadian Subatomic Physics community were extremely important." Helmer, who oversaw the design, fabrication, installation, and commissioning of several key detector components. "The entire SNO team feels greatly honoured to have been awarded this prize," said Dr.
Their results also proved that neutrinos have a tiny mass, where previously they were thought to be massless. The detector is used to look for neutrinos, tiny subatomic particles that are extremely difficult to detect - in fact, billions of neutrinos pass through people's bodies every second with no effect.Īfter more than seven years of data taking, the SNO team of research scientists from 14 different universities and research laboratories in Canada (including TRIUMF), the United States, and Great Britain have used the SNO detector to solve a 30-year-old scientific problem: the discrepancy between the number of neutrinos observed, and the number theoretically predicted, to come from the sun. The detector consists of the world's largest acrylic vessel, holding 1,000 tonnes of heavy water on loan from the Atomic Energy Canada Ltd. SNO operates a giant 10-story tall detector housed in the world's deepest underground laboratory at CVRD-Inco Ltd's Creighton nickel mine near Sudbury, Ontario. Polanyi Award will recognize a recent outstanding advance made by Canadian researchers in any field of the natural sciences or engineering. John Polanyi, winner of the 1986 Nobel Prize for Chemistry. The Natural Sciences and Engineering Research Council (NSERC) created the $250,000 science and engineering research prize in honour of Canadian scientist Dr. Richard Helmer will be among those so honoured. Polanyi Award are the Canadian scientists of the Sudbury Neutrino Observatory (SNO) collaboration, who are being honoured for their groundbreaking research on neutrinos which solved a 30-year-old scientific puzzle. (Vancouver, B.C.) - The winners of the inaugural $250,000 NSERC John C. News Release | For Immediate Release | November 15, 2006