Transcript 中国mini-SONG项目技术方案介绍

An Introduction to mini-SONG Project
Natioanl Astronomical Observatories
Chinese Academy of Sciences
Xiaojun Jiang
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Overview of the mini-SONG project
mini-SONG telescopes
mini-SONG instruments
progress and project schedule
Overview of the mini-SONG project
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Plan to setup on the 4 SONG sites in Northern Hemisphere
Consists of a 50-cm twin-telescope at each site
Scientific goals:
 General multi-color survey of open clusters
Long term multi-color time-domain observations of selected cluster
fields
Superiority:
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Global network groups
Long time baseline
High resolutions in frequency space
Multi-color photometry
mini-SONG telescopes
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Structure:
twin telescope
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Aperture:
50cm
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Mount:
German EQ
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Optical system:
Ritchey-Chrétien
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Focal ratio:
F/3 primary; F/9.5 system
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Focal length:
4753mm ± 25mm
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FOV:
20' x 20'
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Wavelength:
B or V for one telescope and R
for the other (covers Johnson, SDSS, Strömgren
systems)
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Mirror material:
Astro Sitall
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Coating:
Al+SiO2, Enhanced
Aluminum (SiO2/TiO2) Overcoat
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Wave front accuracy: ≤1/8λ@633nm
mini-SONG telescopes cont.
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RC Open Truss Carbon Tube
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Precision Secondary Mirror Focuser
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Conical Secondary Light Baffle
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Lateral roller bearings support mirror cell
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Active computer controlled cooling
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“light weight” Dovetail Plates Dust Cover over primary
mirror
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Focuser capacity: 8Kg
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RC Field Flattener/Corrector
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Direct Drive Mount
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8" RMS pointing accuracy(Zenith distance <70 degree)
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Open-loop tracking: 0.1" over 10sec and 0.35" over
300sec RMS
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Slew speed: 10deg/s for both axes
mini-SONG telescopes cont.
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Dome Design
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Diameter 4m
Total height 2.9m
Total height when parked 2.5m
mini-SONG instruments
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CCD:
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Andor, DZ-936
Pixel size: 13.5μm
Active pixels: 2048x2048 (20'x20')
Filters
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Size: 50mmx50mm
Thickness: 5mm
Positions on each wheel: 4
Progress and project schedule
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2011.6 – Completed project review and evaluation
2011.7 – Completed detailed design, review and evaluation
2011.8~2011.10 – Key components order
2011.11~2012.6 – Telescope structure machining
2011.11~2012.12 – Control sys. development and debugging
2011.11~2012.12 – Software development and debugging
2012.07~2012.09 – Telescope assembly
2012.12 – Complete whole structure assembly, development of control
system/software/networking, etc.
2013.01～2013.04 – On-site installation and commissioning
2013.05 – Acceptance test
Problems
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Sites: no confirmation/permission excepts Chinese site
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Construction: finished preliminary design, need detailed
site info to complete final construction design
Thanks!