![Page 1: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/1.jpg)
Plans for QTT —Overall Introduction
Wang Na
Xinjiang Astronomical Observatory, CAS
May 19-21,2014 Green Bank
![Page 2: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/2.jpg)
Outline • Background • General Plan • QTT Site • Science Goal • Technique Schemes • Progress
2 3rd US-China Meeting 2014-5-19
![Page 3: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/3.jpg)
Background
3 3rd US-China Meeting 2014-5-19
Almost all of our knowledge about the universe are based on the received electromagnetic radiation by the observer, only a small part are from real material (such as meteor)
The transmission window of the atmosphere for radio frequency: 10MHz ~ 1THz(30m ~ 0.3mm)
Radio wavelength spanning: λmax/λmin ~ 3×104 Optical: λmax/λmin ~ 2
![Page 4: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/4.jpg)
SKA,低频阵列,预研 GMRT低频阵列,印度,1998 ALMA,高频阵列,美国,2010年
Background Giant single telescopes
2014-5-19 3rd US-China Meeting 4
中国,FAST 500米,在建 美国 305米,1963年
Arrays
![Page 5: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/5.jpg)
英国76米,1958年
澳大利亚 64米,1961年
德国100米,1972年
美国100× 110米,2000年
Fully steerable telescopes
Background
2014-5-19 3rd US-China Meeting 5
![Page 6: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/6.jpg)
Background
6 3rd US-China Meeting 2014-5-19
佘山25米,1987年 南山25米,1993年
密云50米,2005年 昆明40米,2006年 上海65,2012年
![Page 7: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/7.jpg)
• QiTai radio Telescope (QTT) – Steerable 110m radio telescope
7 3rd US-China Meeting 2014-5-19
General Plan
![Page 8: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/8.jpg)
General Plan
• Features
– Prime/Gregorian paraboloid, Az/El
– Aperture: 110 m
– Fully Steerable
– Active Surface
– Freq Range 150 MHz – 115 GHz
8 3rd US-China Meeting 2014-5-19
![Page 9: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/9.jpg)
General Plan
• China VLBI (CVN): astrometry, space exploration
CVN+QTT: sensitivity increases 1.8 times
CVN+QTT+65m: sensitivity increases 3 times
• EVN
9 3rd US-China Meeting 2014-5-19
Band (cm) EVN
Available Tele SEFD (Jy) (NS 25m)
SEFD (Jy) (QTT)
Ratio improvement
18 10 13 9 30%
13 8 61 17 71%
6 10 14 12 16%
3.6 8 31 21 34%
1.3 6 149 101 33%
![Page 10: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/10.jpg)
General Plan
• Surface Accuracy (rms): – main reflector:
≤0.6mm (no active surface) ≤0.3mm (active surface, long term ≤0.2mm) single panel:≤ 0.07mm
– sub-reflector: ≤0.1mm single panel:≤0.05mm
3rd US-China Meeting 2014-5-19 10
![Page 11: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/11.jpg)
General Plan
• Pointing Accuracy @ 6mm wave length with wind speed≤4m/s, temperature drift≤2℃/h, observation time: 69.5% – blind pointing≤5arcs – repeatability precision≤2.5arcs
• QTT Electric Performances
3rd US-China Meeting 2014-5-19 11
Band 100cm 30cm 5cm 1cm 6mm 3mm
Efficiency
(Optimum El.) 60% 63% 63%
60%
~50%
54%
~30%
30%
~12%
System Noise (K) 30 25 20 20 45 100
![Page 12: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/12.jpg)
General Plan
3rd US-China Meeting 2014-5-19
Type
Band (cm)
RF Freq (GHz)
Focus Feed Poln Science Goals
Single Pixel
100 0.15 – 0.6 Primary Kildal Linear Pulsar, RRT
30 0.6 – 4 Primary Horn Linear Pulsar, RRT, HI, OH, Galaxies
5 2 – 12 Greg. Horn Linear Molecular spectrum, Galaxies; VLBI
1 12 – 36 Greg. Horn Linear Pulsar, H2O, NH3, VLBI
0.6 36 – 50 Greg. Horn Linear Molecular spectrum, High-z CO
0.3 72 – 115 Greg. Horn Linear Molecular spectrum, Galaxies
Dual- Band
13/3.6 2.2 – 2.5
8 – 9 Greg. Horn Circular
VLBI, space exploration, System measurement (3.6cm)
3.6/0.9 8 – 9
30 – 34 Greg. Horn Circular
VLBI, space exploration
Multi- Pixel
15 1 – 2 Primary PAF Linear Pulsar, RRT, HI, OH, Galaxies
0.6 36 – 50 Greg. Horn
(multi Beam) Linear
Molecular spectrum, Galaxies
12
![Page 13: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/13.jpg)
QTT Site
13 3rd US-China Meeting 2014-5-19
Shihezi Village
Qitai
Nanshan
Urumqi
Ulastai
![Page 14: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/14.jpg)
QTT Site
14 3rd US-China Meeting 2014-5-19
• 1.5 km ×2 km basin
• Altitude range from 1730 m to 2250 m
• Surrounding ridges form an isolated layer with outside region
![Page 15: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/15.jpg)
• Elevation of mountain shelter
QTT Site
3rd US-China Meeting 2014-5-19 15
![Page 16: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/16.jpg)
QTT Site
16 3rd US-China Meeting 2014-5-19
• Average annual rainfall of area: – 180 to 200 mm
• Average evaporation capacity of Xinjiang area: – ~2000mm
• Atmospheric water vapour content: – Summer: ~19 mm – Spring and Autumn: ~9mm – Winter: ~3 mm
![Page 17: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/17.jpg)
QTT Site
17 3rd US-China Meeting 2014-5-19
• Temperature range:
– max +29.3 °, min-26.6 °
• Temperature drifting:
Temperature
drifting Ratio
≤ 5 ℃/hr 99.0% ≤ 3 ℃/hr 92.7% ≤ 2 ℃/hr 82.7%
![Page 18: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/18.jpg)
QTT Site
18 3rd US-China Meeting 2014-5-19
Roses diagram
• Frequency distribution of max. wind speed:
Wind speed Ratio
Qitai_Day Qitai_Night Qitai_Average GBT ≤4m/s (3 beaufort scale) 48.9% 83.0% 65.9% 45.9% ≤6m/s (4 beaufort scale) 74.3% 92.9% 83.6% 64.5% ≤8m/s (5 beaufort scale) 91.0% 96.6% 93.7% 79.2% ≤10m/s (6 beaufort scale) 96.7% 98.3% 97.5% 88.9%
≥17m/s (8 beaufort scale) 0.21% 0.06% 0.14% 0.5%
![Page 19: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/19.jpg)
QTT Site
19 3rd US-China Meeting 2014-5-19
• RFI: SKA-FAST measurement and processing standards
• Most interference are recognizable: − Measured 150 MHz ─ 13 GHz − 2 or 3-G mobile wireless communication (UHF, L, S band) − broadcast television (analog digital, VHF, UHF band) − differential rotation system of wireless satellite television (UHF, C
band) − satellite navigations
![Page 20: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/20.jpg)
3rd US-China Meeting 2014-5-19 20
Science Goal Astronomy
• Molecular spectra observations • High precision pulsar timing • Active galactic nuclei • Dark matter • VLBI astrometry, astro-dynamics and space
VLBI • Sky survey: detecting organic molecule and
sulphur chain molecule Application
• VLBI orbit measurement for space exploration • Pulsar time standard • Deep space pulsar autonomous navigation
NASA/GSFC
![Page 21: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/21.jpg)
Science Goal
21 3rd US-China Meeting 2014-5-19
(Lyne, 2010)
High precision pulsar timing
![Page 22: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/22.jpg)
Science Goal Gravitational wave detection
22 3rd US-China Meeting 2014-5-19
PSR J1045-4509, DM correction, reduces residual by ~50%
20cm
50cm
PSR J1744-1134, polarization correction, residual reduces from 487 to 195ns
NANOGrav, IPTA, PPTA
Best: ~50 ns
![Page 23: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/23.jpg)
Science Goal • Follow up obs. of FAST pulsar survey • Spectrum survey at 6mm & 3mm
23 3rd US-China Meeting 2014-5-19
![Page 24: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/24.jpg)
24 3rd US-China Meeting 2014-5-19
General • Structure design: high antenna efficiency • Servo control: accurate pointing • Active surface: quasi closed-loop control • Track: welded track + heavy load • Structure and electronics: temp under -30℃ • Rx: wide band feed • Multi-beam / PAF
15°
ring1…… ring22
15°
5m2, 2856 12.5m2, 888
Technique Schemes
![Page 25: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/25.jpg)
Technique Schemes Telescope efficiency
– Conformal design – Homology design – Active surface
25 3rd US-China Meeting 2014-5-19
Frequency (GHz)
Ape
rture
effi
cien
cy
Gai
n (K
/Jy)
![Page 26: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/26.jpg)
Technique Schemes Active surface
• Deformation: – Gravity, thermal, temperature drifting, wind load
• FEM to Quick measurement: OOF • Closed-loop control
26 3rd US-China Meeting 2014-5-19 GBT:25mins at Q-band 25m
![Page 27: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/27.jpg)
Technique Schemes
Wheel-track antenna mount: 4 or 6 feet support
Max. load
2014-5-19 3rd US-China Meeting 27
![Page 28: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/28.jpg)
0 10 20 30 40 50 600
10
20
30
40
50
60Technique Schemes
Segmented main surface – Single joint, 27 rings, ~4000@4m2 – Secondary joint
28 3rd US-China Meeting 2014-5-19
1x2 strut
2x2-1 strut
2x2-2 strut
1x3 strut
Panel : Back sub-truss 1:1.53 1:1.27
![Page 29: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/29.jpg)
Technique Schemes
Pointing correction • Thermal deformation • Temperature deformation • Wind load
29 3rd US-China Meeting 2014-5-19
![Page 30: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/30.jpg)
Technique Schemes
2014-5-19 3rd US-China Meeting 30
Increase the resonance frequency
Increase the rigidity, reduce structure transmission impassable range
Reduce the systematic and random error of servo system
PI regulator+
Front feed compound control(FF)+
LQG
Digital control sys
Compound control
technique
Low speed large torque
drive
Telescope control
![Page 31: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/31.jpg)
Technique schemes
Welded wheel track – Heavy load: ~5000 ton – Temperature range-30—+30℃
31 3rd US-China Meeting 2014-5-19
![Page 32: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/32.jpg)
Technique Schemes
Sub-reflector
– carbon fiber
– 6-pole adjust system
– Rotate to change Rx
32 3rd US-China Meeting 2014-5-19
![Page 33: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/33.jpg)
33 3rd US-China Meeting 2014-5-19
Technique schemes
Four ridge feedBW: 10 octave band • Better radiation pattern • High-pass filter
ELEVEN feed • Simplify structure • Compact, low cost • Stable phase center • Constant beam width
Ultra-wideband feed – Increase S/N – Simultaneous multi spectrum line obs.
![Page 34: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/34.jpg)
Technique Scemes
34 3rd US-China Meeting 2014-5-19
Software
![Page 35: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/35.jpg)
Progress
• Leading group by Nuer Baikeli (Chairman of XJ) Bai Chunli (President of CAS)
• Leading group office / Site headquarters Liu Hua (secretary of XJ government)
35 3rd US-China Meeting 2014-5-19
![Page 36: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/36.jpg)
Progress
36 3rd US-China Meeting 2014-5-19
• Evaluations organized by CAS & NAO • Ceremony for laying foundation • Manufactures involved • Design
![Page 37: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/37.jpg)
Progress
37 3rd US-China Meeting 2014-5-19
2012 Nov. 29—Dec. 1 QTT International Advisory Workshop
Suggestions about conceptual design, 3mm science, operating, cost
![Page 38: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/38.jpg)
International collaboration:
– NRAO: Memorandum of Agreement for Scientific and Technical Consultation on the Planned Qi-Tai Radio Telescope (QTT)
– KASI, NAOJ, MPIfR
Progress
2014-5-19 3rd US-China Meeting 38
![Page 39: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/39.jpg)
Progress Infrastructure
– Land acquisition: approved – Herdsman relocate: 130 families, move in 3 years – Classified road: build this year – Power: satisfy the infrastructure requirement – Water supply plan: assessed – Fiber connection: done for construction period – RFI & meterological daily monitoring
3rd US-China Meeting 2014-5-19 39
![Page 40: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/40.jpg)
Progress Site planning
40 3rd US-China Meeting 2014-5-19
![Page 41: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/41.jpg)
QTT Site - Radio Protection Area
3rd US-China Meeting 2014-5-19
radio quiet zones @different protection levels: – core area – restricted area – coordination area
41
![Page 42: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/42.jpg)
Progress
Recent
– Project Approval Intension: Qitai Station for Astronomical
Observation and Popular Science Education
– Funding from XJ this year
2014-5-19 3rd US-China Meeting 42
![Page 43: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/43.jpg)
Summary
• QTT: general purpose telescope
• Site is good for 6mm and above
• Engineering specifications: 6mm
• Design aimed to 3mm
• Technique challenges: structure, pointing control, surface
accuracy, active surface adjust, wideband Rx
• Science: pulsars, spectrum line, AGN, VLBI
• Present: infrastructure construction moving on
• Pursue for approving by 13th 5-year plan
43 3rd US-China Meeting 2014-5-19
![Page 44: Plans for QTT —Overall Introduction · —Overall Introduction Wang Na . Xinjiang Astronomical Observatory, CAS . May 19-21,2014 Green Bank . Outline • Background • General](https://reader034.vdocuments.site/reader034/viewer/2022051808/600b20c72a48f33f3c4e27be/html5/thumbnails/44.jpg)
44 3rd US-China Meeting 2014-5-19