The Large The Large Synoptic Survey Synoptic Survey

Telescope:Telescope:The power of wide-fieldThe power of wide-field

imagingimaging

Michael Strauss, Princeton University

Large Synoptic Survey Large Synoptic Survey TelescopeTelescope

An effective aperture of 6.9 An effective aperture of 6.9 meters, and a camera with a 9.6 meters, and a camera with a 9.6 degdeg22

field of view, gives an field of view, gives an étendue of 320 métendue of 320 m22 deg deg22..

0

40

80

120

160

200

Relative Figure of Merit

LSST SNAP(opt) DES PS-4 Subaru CFHT SDSS MMT

Time (x10)

Stellar

Galaxies(x2)

Relative

Relative étendue

étendue

Telescope will be on Telescope will be on Cerro Pachón in Chilean Cerro Pachón in Chilean

AndesAndesTelescope will be dedicated to the Telescope will be dedicated to the survey, and will operate for ten survey, and will operate for ten

years.years.

Three-mirror design, Three-mirror design, with tertiary built with tertiary built

intointo primary primary

The LSST opticsThe LSST optics

Camera will have Camera will have 3.2 Gigapixels, 3.2 Gigapixels, each 0.2”. Six each 0.2”. Six filters, ugrizy. filters, ugrizy.

A very fast compact A very fast compact designdesign

Photometric system similar Photometric system similar to SDSS (with addition of to SDSS (with addition of

yy filter) filter)

A dedicated 10-year A dedicated 10-year surveysurvey

Main survey will cover 20,000 square Main survey will cover 20,000 square degrees, with over 300 15-second degrees, with over 300 15-second exposures in each of exposures in each of r r, , ii, , zz, and , and YY..

55 depth after two exposures: 23.9 ( depth after two exposures: 23.9 (uu), ), 25.0 (25.0 (gg), 24.7 (), 24.7 (rr), 24.0 (), 24.0 (ii), 23.3 (), 23.3 (zz), ), 22.1 (22.1 (yy))

Depth at end of the survey: 26.2 (Depth at end of the survey: 26.2 (uu), ), 27.4 (27.4 (gg), 27.6 (), 27.6 (rr), 26.9 (), 26.9 (ii), 26.1 (), 26.1 (zz), ), 24.8 (24.8 (yy))

Perhaps 10% of the time will be devoted Perhaps 10% of the time will be devoted to cadences designed to observe faint to cadences designed to observe faint distant Kuiper Belt Objects, and to get distant Kuiper Belt Objects, and to get good light curves for supernovae.good light curves for supernovae.

Extremely high-quality Extremely high-quality datadata

Median delivered image quality of 0.67”Median delivered image quality of 0.67” Can cover all the available sky in a Can cover all the available sky in a given filter in roughly 3 nights. given filter in roughly 3 nights.

Probes of variability on timescales Probes of variability on timescales from 15 seconds to 10 years. from 15 seconds to 10 years.

Stellar photometric calibration to 1% Stellar photometric calibration to 1% or better; stellar repeatability to or better; stellar repeatability to 0.5%.0.5%.

Astrometry to 10 mas per visit, Astrometry to 10 mas per visit, allowing proper motions uncertainty of allowing proper motions uncertainty of 0.2 mas/year, and parallax uncertainty 0.2 mas/year, and parallax uncertainty of 1 mas over the course of the survey. of 1 mas over the course of the survey.

SimulatiSimulations of ons of LSST sky LSST sky coverage coverage in six in six bands; bands; equatoriequatorial al coordinacoordinates. tes.

First light as early as the end of 2015 First light as early as the end of 2015 (subject to funding), with a one-year (subject to funding), with a one-year commissioning period.commissioning period.

Major construction proposal submitted to Major construction proposal submitted to NSF in February 2007. There is a hope NSF in February 2007. There is a hope for substantial funds for the camera for substantial funds for the camera from DOE. from DOE.

The project is currently being discussed The project is currently being discussed by the US 2010 Decadal Survey. by the US 2010 Decadal Survey.

Budget: $390 million in 2006 dollars Budget: $390 million in 2006 dollars (including 30% contingency), plus $45 (including 30% contingency), plus $45 million per year in operating costs.million per year in operating costs.

The LSST The LSST construction construction proposal was proposal was submitted to submitted to NSF in NSF in February February 2007. 2007. We’re We’re waiting for waiting for the the recommendatirecommendation of the on of the Decadal Decadal Survey.Survey.

Primary/Tertiary has Primary/Tertiary has been cast!been cast!

Who is involved?Who is involved? Brookhaven National LaboratoryBrookhaven National Laboratory, , California Institute of California Institute of

Technology, Carnegie-Mellon, Columbia UniversityTechnology, Carnegie-Mellon, Columbia University, , Cornell, Drexel UniversityCornell, Drexel University, , Google Inc.Google Inc., Harvard-, Harvard-Smithsonian Center for Astrophysics, IN2P3 (Paris), Johns Smithsonian Center for Astrophysics, IN2P3 (Paris), Johns Hopkins University, Kavli Institute for Particle Astrophysics Hopkins University, Kavli Institute for Particle Astrophysics and Cosmology at Stanford University, Las Cumbres and Cosmology at Stanford University, Las Cumbres Observatory, Lawrence Livermore National Laboratory, Observatory, Lawrence Livermore National Laboratory, National Optical Astronomy Observatory, National Optical Astronomy Observatory, Princeton Princeton UniversityUniversity, Purdue University, Research Corporation, , Purdue University, Research Corporation, Rutgers University, Space Telescope Science Institute, Rutgers University, Space Telescope Science Institute, Stanford Linear Accelerator Center, The Pennsylvania Stanford Linear Accelerator Center, The Pennsylvania State University, The University of Arizona, University of State University, The University of Arizona, University of California, Davis, University of California, Irvine, University California, Davis, University of California, Irvine, University of Illinois at Urbana-Champaign, University of of Illinois at Urbana-Champaign, University of Pennsylvania, University of Washington, Vanderbilt Pennsylvania, University of Washington, Vanderbilt University, and the Chilean astronomical community.University, and the Chilean astronomical community.

A Series of Science A Series of Science CollaborationsCollaborations

Weak lensing (Weak lensing (Bhuvnesh Jain and Dave WittmanBhuvnesh Jain and Dave Wittman)) Strong lensing (Strong lensing (Phil MarshallPhil Marshall)) Supernovae (Supernovae (Michael Wood-VaseyMichael Wood-Vasey)) Large-scale structure/BAO (Large-scale structure/BAO (Hu ZhanHu Zhan)) AGN (AGN (Niel BrandtNiel Brandt)) Galaxies (Galaxies (Harry FergusonHarry Ferguson)) Galactic structure (Galactic structure (Beth WillmanBeth Willman)) Stellar populations (Stellar populations (Abi Saha and Kevin Abi Saha and Kevin CoveyCovey))

Variability and transients (Variability and transients (Lucianne Lucianne Walkowicz andWalkowicz and Josh BloomJosh Bloom))

Solar system (Solar system (Steve Chesley and Lynne JonesSteve Chesley and Lynne Jones))

Final thoughtsFinal thoughts LSST is the most ambitious (and longest LSST is the most ambitious (and longest timescale) of a whole series of planned timescale) of a whole series of planned wide-field imaging surveys.wide-field imaging surveys.

The data will be made public The data will be made public immediately, especially important for immediately, especially important for transients. transients.

The need for spectroscopic follow-up The need for spectroscopic follow-up and support (especially calibration of and support (especially calibration of photo-zs) is obvious; many photo-zs) is obvious; many opportunities for synergy with bigBOSS! opportunities for synergy with bigBOSS!