Transcript 2.4m Telescope Group Yunnan Observatory of CAS

2.4m Telescope Group
Yunnan Observatory of CAS
Status of LiJET Project
&
The Coude Echelle Spectrograph
for the Lijang 1.8m Telescope
China-Japan Collaboration Project Meeting @Xinglong
Chang, Liang 常 亮
Yunnan Astronomical Observatory
雲南天文台
[email protected]
2.4m Telescope Group
Yunnan Observatory of CAS
1.
LiJiang Extremely High Precision ExtraSolar Planet Tracker
1）LIJET Project collaborators:
China: USTC, YNAO, NJU
USA: UFL
Supported by Chinese Academy of Science and National Science Foundation of China, University
of Florida, and National Science Foundation of USA and also participating institutions including
YNAO, USTC, and NJU.
2 ）Our Design Goals:
* Use low-cost, compact, robust, low maintenance, but high precision and throughput Doppler
instruments
* Target bright F,G,K dwarfs (V<8) with slow rotation for detection of super Earth mass
planets, including habitable ones
* Integrate at least 15 min to minimize RV noises from stellar oscillations for low mass planet
detection
2.4m Telescope Group
Yunnan Observatory of CAS
* A nearly perfect match of ~15 min exposure time requirements and photon noise limit
offered by a 2 meter telescope for 0.5-1 m/s
• For astro-seismology, only target V<5 stars and ~1 min exposures
* Target faint solar type stars up to V~12 for moderate-high Doppler precision measurements
• Offer continuous high precision radial velocity measurements for V<8 F,G,K stars with 0.51 m/s Doppler precision in 30 min or less
• Follow up planet candidates from SDSS-III MARVELS planet survey
• Observe other science targets provided by the consortium members
* Network resources will be available to the entire consortium members
2.4m Telescope Group
Yunnan Observatory of CAS
3）. Summary of optical characteristics
Telescope
Lijiang 2.4m, F/8
Fiber Input Focal Ratio
F/4
Fiber Output Focal Ratio
F/4
Slit Size
72um
Main disperser
R2 Echelle, 63deg blaze, 87 l/mm
Cross disperser
PBM2Y prism, 45 deg apex angle
Collimated beam size
85mm
Detector
4096 x 4096 CCD, 15 micron pixels
Spectra Range
RVM: 390nm-690nm; DEM: 390nm-1000nm
Spectra Resolution
RVM: R=18000, DEM: R=27000
Fiber core diameter
RVM: 105um; DEM: 50um
2.4m Telescope Group
Yunnan Observatory of CAS
LiJET setup in the UF lab
LiJET inside
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2.4m Telescope Group
Yunnan Observatory of CAS
LIJET telescope interface including a fiber feeding system, a fiber tip guiding and a calibration fiber
light source. The calibration light was fed from the calibration lamps on the calibration bench inside
the instrument control chassis
2.4m Telescope Group
Yunnan Observatory of CAS
4 ) LiJET Status
☺ LiJET already be packed in UF, will ship to China for commissioning in December or Next
January（It depends on China Customs）
☺ LiJET RMS RV errors are close to the required values, <1.5m/s for bright calibration sources in
UF lab now.
☺ We already built a instrument room for LiJET in 2.4m telescope basement. It’s a temperature
and humidity stable room, temperature design goal is ±0.5℃,it have reached ±0.2℃ precision in
3 months. And humidity is controlled in 40%-60%.
☺ We have prepared all tools and spare parts for LiJET set up for commissioning.
2.4m Telescope Group
Yunnan Observatory of CAS
***Commissioning Plan, Instrument Testing and Early Science***
☺ ~6 months of commissioning (weather and instrument unpredicted nature and past
EXPERT experience), one run/month, ~15 nights/run;
☺ First run with three weeks, 1st week, hardware installation, 2nd week integration with
the telescope, 3rd week trial observations;
☺ Results to meet proposal requirements;
☺ Short (<14 days) and long term (~1 yr) RMS precision;
☺ Commissioning targets (≥2 RV stable starts, ≥2 RV known planets (one with short period
and one with > 1 month period);
☺ Early Science: No promise of any science results, but demonstrate its science capability;
☺ Commissioning science targets: In Aug. 12th, 2010, the LiJET Project Collaborators
discussed detailed commissioning science targets at Hefei City; It includes ~1 m/s science,
~3‐5 m/s science within 6 months and other science targets and plan.
2.4m Telescope Group
Yunnan Observatory of CAS
2. The Coude Echelle Spectrograph for the Lijang 1.8mTelescope
1)1.8m Telescope optical System
•Cassegrain system
•Primary Mirror: Paraboloid,
Clear Aperture:1760mm
Focal Ratio: F/1.5
•Two Secondary Mirrors: Hyperboloid
•Coude Focus : F/# = 89
•Nesmyth Focus: F/# = 12
•FOV: Nasmyth:18’×18’, Coude:±1.5’
2.4m Telescope Group
Yunnan Observatory of CAS
Alt-Azimuth Mounting
The Mass:25000kg
The Hight：7.2m
2.4m Telescope Group
Yunnan Observatory of CAS
2.4m Telescope Group
Yunnan Observatory of CAS
2.4m Telescope Group
Yunnan Observatory of CAS
2）1.8m Telescope Reducer Design
Design Description：
* From F/89 to F/45
* FOV: 3’
* Spectra Range:330nm-1100nm
Blue Region: 331.17nm-577.42nm, Central wavelength 402.13nm
Red Region 562.98nm-1103.39nm, Central wavelength 703.73nm
Clear Aperture: 149.03 mm
2.4m Telescope Group
Yunnan Observatory of CAS
2.4m Telescope Group
Yunnan Observatory of CAS
Telescope
Lijiang 1.8m, F/89
Input Focal Ratio
Lijiang 1.8m, F/89
F/45
F/45
Main disperser
R2 echelle grating
79 gr/mm
R2 echelle grating
31/.6 gr/mm
Cross disperser
60 degree UBK7 prism.
60 degree ZF3 prism.
Spectra Range
330-580nm
580-1100nm
8200
37000
170000
12000
44000
170000
Spectra Resolution
WHEN ?????
2.4m Telescope Group
Yunnan Observatory of CAS
THE END
THANKS