  A few times a century, a core collapse supernova (CCSN) occurs in our galaxy.
When such galactic CCSNe happen, over 99\% of its gravitational binding energy
is released in the form of neutrinos. Over a period of tens of seconds, a
powerful neutrino flux is emitted from the collapsing star. When the exploding
shock wave finally reaches the surface of the star, optical photons escaping
the expanding stellar envelope leave the star and eventually arrive at Earth as
a visible brightening. Crucially, although the neutrino signal is prompt, the
time to the shock wave breakout can be minutes to many hours later. This means
that the neutrino signal will serve as an alert, warning the optical astronomy
community the light from the explosion is coming. Quickly identifying the
location of the supernova on the sky and disseminating it to the all available
ground and spaced-based instruments will be critical to learn as much as
possible about the event. Some neutrino experiments can report pointing
information for these galactic CCSNe. In particular, the Super-Kamiokande
experiment can point to a few degrees for CCSNe near the center of our galaxy.
A CCSN located 10 kpc from Earth is expected to result in a pointing resolution
on the order of 3 degrees. LSST's field of view (FOV) is well matched to this
initial search box. LSSTs depth is also uniquely suited for identifying CCSNe
even if they fail or are obscured by the dust of the galactic plane. This is a
proposal to, upon receipt of such an alert, prioritize the use of LSST for a
full day of observing to continuously monitor a pre-identified region of sky
and, by using difference imaging, identify and announce the location of the
supernova.
