SNO, SNEWS, and the Next Galactic Supernova
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 Clarence J. Virtue, Laurentian University, for the SNO Collaboration  

A type II supernova releases 99% of its energy in the form of
neutrinos over a brief timescale of tens of seconds. These neutrinos
escape from the proto-neutron star following core collapse and are an
excellent window into the dynamics of the supernova process itself,
whose detailed understanding is seen as one of the remaining ?grand
challenges? of computational physics. The Sudbury Neutrino Observatory
(SNO) is one of several detectors worldwide capable of observing
galactic supernovae, through the detection of hundreds to thousands of
neutrino interaction events. Current models of the supernova process
have robust and distinguishing features in their neutrino energy,
flavour and luminosity spectra. SNO?s capabilities to extract neutrino
energy and flavour distributions are therefore important tools in
providing experimental constraints to supernovae theory. A tantalizing
aspect of supernova neutrino detection is that the neutrinos precede,
by up to 10 hours, the visible eruption of the mantle of the
star. This potentially allows for an alert to be issued before the
supernova is otherwise detectable. Though galactic supernovae are rare
events, occurring approximately every 10-50 years, a false
announcement from a neutrino detector would be very disruptive to the
observing programs of astronomical instruments around the
world. However, a prompt announcement following on the real-time
observation of a supernova neutrino signal would also be a unique
opportunity for the astronomical community to observe a near-by
supernova with modern instruments from the earliest possible
moment. In order to ensure a prompt and positive alert several
neutrino detectors have formed the Supernova Early Warning System
(SNEWS). This presentation will outline the potential of SNO for
supernova physics and the techniques in place to maximize this
scientific opportunity by providing a reliable and timely alert to the
astronomical community through SNEWS.