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SUMMARY:Mapping the Transient Sky with Gaia - Simon Hodgkin
DTSTART:20181121T134500Z
DTEND:20181121T141500Z
UID:TALK111433@talks.cam.ac.uk
CONTACT:Dr Giovanni Rosotti
DESCRIPTION:Gaia is an ESA cornerstone mission\, delivering precision phot
 ometry\, astrometry\, spectrophotometry\, and spectroscopy\, all based on 
 regular image-scanning the sky through two telescopes and the largest foca
 l-plane array (1Gpixel) yet launched. This\, by design\, makes the time-do
 main the heart of Gaia’s scientific requirements and capabilities. Gaia 
 is monitoring the sky with cadences of seconds (between CCDs)\, hours (bet
 ween fields-of-view) and weeks (between visits)\, with real-time source de
 tection implemented by a fixed\, available\, and well understood on-board 
 algorithm. Every Gaia source obtains near-simultaneous spectrophotometry.\
 n\nThe GaiaAlerts system has been running routinely and reliably since Jan
 uary 2016\, publishing 6 transients per day (see http://gsaweb.ast.cam.ac.
 uk/alerts/home)\, using well-defined selection criteria. We scan the whole
  sky exploring into the Galactic plane and crowded regions which are typic
 ally hard to do from the ground. I will describe the challenges we face in
  searching through half a billion CCD measurements every day to identify a
 nd publish Gaia's transient events. I will discuss the properties of the a
 lerts published to date and highlight some of our most interesting discove
 ries. I will examine the completeness and biases in our selection criteria
 \, and look ahead to ongoing updates to the system\, including making the 
 most of Gaia's spectrophotometry and astrometry.
LOCATION:Sackler Lecture Theatre\, IoA
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