Transcript LSST Phys Colloquium

Exploration
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Wavelength
Angular resolution
Area surveyed
Depth
Time resolution
• Large aspheric optics
• Microelectronics
• Software
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What if we could go faint fast
over the entire visible sky?
• Unprecedented Planetary Probes
 NEO > 250m, KBO, Comets, debris
• Probe Dark Energy & Dark Matter
• Open the Time Window
 Faint Transients (GRB, SN, …?)
 Variability studies: stars, galaxies…
Requires: reach 24 V mag in ~10 sec
over ~5-10 sq deg field
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8.4m diameter primary mirror
7 square degree field of view
>15000 Gbytes per night
Real-time analysis
Celestial Cinematography
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LSST Data Flow Model
~600 MB/sec peak, 15 sec cycle
Calib. insertion
Stacked Sum
“Static” DB
Working Flat
Readout and Flatfield
Image Difference
~ 18 TB/night
Boxcar Flat Gen
Variability Detection
103 – 104/night?, 1-10 GB?
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Known Obj?
Update LC DB
10-100GBytes/night?
Update Calib DB
Classifier
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Alert, export:
• photometry
• flags
• Light Curve...
LSST 2017: 15 Petabyte
time-tagged imaging database
1 TB photometric catalog
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Petabytes on spinning disks
Now
LSST
• Not a problem in 2008
• Multi-site disk farms
• Co-located computing
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A Challenge: Software
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Key Project Pipelines
Robust Automated Variability Discrimination
Automated Variability Classification
Software adaptive optics – PSF control
Detection Efficiency Calibration
Lossy mining algorithms
Data visualization
We can start now, and are doing so.
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Key Science Pipelines
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multi-taps & realtime calibration
defined data products
data quality verification
duplicate pipelines for testing
industrial model
build on SLOAN, DLS, S-MACHO
Data Quality Assessment
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Challenge:
Craft the database and tools to
enable answers to unanticipated
questions
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LSST Precursor Projects
• SDSS
• Deep Lens Survey
• Super MACHO
• RAPTOR
80-member LSST Collaboration
has members from all these
projects
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The Large Synoptic Survey Telescope –
Massively Parallel Astronomy
DATA PUBLIC Simultaneously address:
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Solar System Probes: Earth-crossing asteroids, Comets, TNOs
Space assets & space junk to 1 cm
Dark matter/dark energy via weak lensing
Dark matter/dark energy via supernovae
Galactic Structure encompassing local group
Dense astrometry over 30000 sq.deg -> deep proper motion science
Gamma Ray Bursts and transients to high z
Gravitational mlensing
Variable stars/galaxies
QSO time delays vs z
Transients to 25 mag: the unknown
5-band 27 mag photometric survey
Unprecedented many Pbyte time-tagged photometric database