Development of the optical system for the SST-1M telescope ...
SST – Space Solar Telescope
description
Transcript of SST – Space Solar Telescope
SST – Space Solar TelescopeSST – Space Solar Telescope
SatelliteSatellite
Solar synchronous circular orbit
Orbit height: 735 km
Inclination: 98.3°Period: 99.3 min
Attitude: accuracy ±6", stability ±3"/s
Weight: 2 ton
Duration: 3 years
Launch: LM-4B
PayloadPayload MOT: with a 2-D polarizing spectrograph for
simultaneously working in 8 channels EUT: viewing the solar corona and transition
region at various temperatures HWT: whole sun viewing WBS: investigating high energy flare
process SIR: nonthermal electron populations
MOT 0.1 2.8'×1.5' 8 channels
2×10 -4
EUT 0.5 8.5'×8.5' 4 channels
HWT 1 0.7°×0.7°
WBS -ray, hard x-ray, soft x-ray
SIR 1-60 MHZ
Correlation Tracker Correlation Tracker
Sensitivity 0.01
Time constant <1 ms
Tracking accuracy ± 0.015 Control rang ± 7.5´
Close-loop bandwidth 100 Hz
CT testCT test horizontal 10Hz, vertical 11Hz, amplitude ±6 pixels
Loop closed Loop opened
CT open loop CT close loop
On Board Data ProcessingOn Board Data Processing
PP
MM
DSP DSP
CEU
OBDH
DL
EUT EUT (Phase A requirements)(Phase A requirements)
Based on the EUVSAT proposal. Consists of a bundle of four normal incidence telescopes mounted in a vacuum vessel, which should overlap, be well aligned and synchronized with each other and with the images of the MOT.
Field of view 8.5’×8.5’
Pixel resolution 0.25”
Format 2048 2048
Wave length 12.8 17.1 19.5 30.4 nm
(subject to change)
DetectorDetector
A CCD imager is to be used with format
changing optics (fiber optic taper) in front of it. In order to achieve high sensitivity, an image
intensifier is proposed. A front phosphor screen is needed to
converse EUV photons to visibles.
Camera Configuration
The proposal of CIOM The proposal of CIOM
Wave length 17.1nm
FOV 8.58.5Pixel resolution 0.4(0.25)
Focal length 7.4 m
Distance between Mirrors 1.817 m
From PM to FP >0.1 m
Primary Mirror 120 mm
Secondary mirror 48 mm
Camera system RequirementsCamera system Requirements1. Inputs: EUV image pixel & Format:
9m× 9m (0.25), 2048 ×2048 Wavelengths &
EUV Photon flux per pixel per second:
(TBC)Wavelengths 12.8 17.1 19.5 30.4
Photon flux 7.3810-
4(quiet)
>710 (flare)
125 80 189
Camera system RequirementsCamera system Requirements
2. Radiometric performances: Dynamic range & linearity:
>2500, 0.5% in full range 12-bits digitization SNR: >250
Camera system RequirementsCamera system Requirements
3. Temporal Resolution: < 2 sec.
4. Dimensions and Weights Overall size:
<100mm×150mm Total Weight:
<2.5Kg/each Camera set
Camera system RequirementsCamera system Requirements
5. Power supply: 25~30v input , <10 watt/each camera set6. Operational Environments Radiational: ToT: 20Krad(Si) SEU/L: TBD Thermal: -20ºC~+50ºC, passive cooler for CCDs EMC: TBD Vibration, Shock, etc.
Front illuminated CCD, size 2048×2048 pixels.
Pixel size on CCD 14 m × 14 m, resulting in 28.6mm × 28.6mm image size.
CCD operated in full-frame mode. Readout simultaneously through 2
channels; failure mode with readout through the remaining functional channel.
CCD operated in MPP mode, with low dark charge and noise.
Correlated double sampling (CDS) with digitizing by 12 bit ADCs.
Camera System pecificationsCamera System pecifications
Main Difficulties on EUT Main Difficulties on EUT instrumentationinstrumentation
Resolution: the optics and the detector
Test on observation wavelength.
EUT Financing EUT Financing
Before 2003 0.8M RMB NAOC
2003 2.0M RMB NSFC
2004 2.0M RMB NAOC
NATIONAL ASTRONOMICAL NATIONAL ASTRONOMICAL
OBSERVATORYOBSERVATORY