LSST Basic Configuration
Current pdf format of Baseline Configuration
(Last Updated 02-27-2007) Click here to view the Science Requirements Summary table
System
- Representative Key Science Missions:
- Dark energy
- Solar system survey
- Optical transients
- Galactic map
- First light schedule: Spring, 2014
- Sky coverage: 20,000 degrees2 (General Survey)
- Standard cadence (per visit): 15 sec expose + 1 sec shutter overhead, 2 sec read, 15 sec expose + 1 sec shutter overhead, 2 sec read, 5 sec slew = 39 sec total
- Etendue ( AΩ ): 319 meter2degrees2
- Field of View: 3.5 degrees (9.6 square degrees)
- Effective clear aperture (On-Axis): 6.68m (adjusted for obscuration)
- Wavelength coverage: 320nm to 1080nm
- Number of active filters: five
- Initial filter set (FWHM points - nm)
- u: 350nm to 400nm
- g: 400nm to 552nm
- r: 552nm to 691nm
- i: 691nm to 818nm
- z: 818nm to 922nm
- Y: 948nm to 1060nm
Telescope and Site
- Optical Configuration: 3-mirror modified Paul-Baker with 3 element refractive corrector
- Final f-ratio: f/1.234
- Plate scale: 50.9 microns/arcsec
- Image diameter at focal plane: 64 cm
- Mount configuration: Alt - Azimuth
- Primary mirror diameter (physical): 8.40 m
- Primary mirror optical aperture: 8.36 m
- Secondary mirror diameter: 3.40 m
- Tertiary mirror diameter: 4.96 m
- Overall system length: 6.39 m
- First camera refractive lens diameter: 1.55 m
- Residual design aberrations (mean 80% encircled energy
diameter for each filter band)
- u: 0.26 arcsec
- g: 0.26 arcsec
- r: 0.18 arcsec
- i: 0.18 arcsec
- z: 0.19 arcsec
- Y: 0.20 arcsec
- Step-and-settle time: < 10 seconds
- Atmospheric dispersion corrector: Not required
- Site: Cerro Pachón, Chile
Camera
(includes focal plane, electronics, refractive corrector lenses, shutter, filters, filter mechanism, dewar, body)
- Pixel count: 3.2 Gpixels
- Pixel pitch: 10 microns
- Readout time: 2 sec
- Dynamic range: 16 bits
- Nominal exposure time: 15 seconds
- Plate scale: 50.9 microns/arcsec
- Focal plane temperature: -100°C
- Camera rotation range: ±90 degrees
- Filter change time: 120 seconds
Data Management
- Real-time alert latency: 60 seconds
- Nightly data generation rate
- Raw pixel data: 15 Tbytes (16 bit)
- Image through pipelines: 30 Tbytes raw science (32 bits) + 108 TB (32 bit) intermediate images
- Archived images + metadata: 15 + 1 Tbytes (32 bits compressed to 16 bits)
- Catalogs (transient phenomena): 1 Tbyte (32 bits compressed to 16 bits)
- Data release volume (average per release)
- Source Catalog: 560 TB
- Deep Object Catalog: 140 TB
- Yearly data archive rate (average)
- Images: 6.5 Pbytes
- Catalogs: 6.5 Pbytes
- Metadata: 0.5 Pbytes
- Total disk storage
- Summit / Telescope site: 100 Tbytes (4 nights + spare capacity, fixed over 10 yrs)
- La Serena Base Facility: 200 Tbytes (4 nights + spare capacity, fixed over 10 yrs)
- NCSA Archive Center (Catalogs): 70 Pbytes (1 catalog release per year over 10 yrs)
- NCSA Archive Center (Images): 65 Pbytes (total image archive)
- Cache and Spare: 15 Pbytes (total over 10 yrs)
- Nominal computer requirement
- At Telescope site: < 1 Tflops
- At base site: 25 Tflops
- At Archive Center: 100 Tflops
- Communications Bandwidth
- Telescope to base site: 10 Gbits/sec
- Base site to archive: 2.5 Gbits/sec