PERFORMANCE OF THE TRAO 13.7-M TELESCOPE WITH NEW SYSTEMS

다국어 초록 (Multilingual Abstract)

We report the performance of the 13.7-meter Taeduk Radio Astronomy Observatory (TRAO) radio telescope. The telescope has been equipped with a new receiver, SEQUOIA-TRAO, a new backend system, FFT2G, and a new VxWorks operating system. The receiver system features a 16-pixel focal plane array using high-performance MMIC preamplifiers; it shows very low system noise levels, with system noise temperatures from 150 K to 450 K at frequencies from 86 to 115 GHz. With the new backend system, we can simultaneously obtain 32 spectra, each with a velocity coverage of 163 kms¯1 and a resolution of 0.04 kms¯1 at 115 GHz. The new operating system, VxWorks, has successfully handled the LMTMC-TRAO observing software. The main observing method is the on-the-fly (OTF) mapping mode; a position-switching mode is available for small-area observations. Remote observing is provided. The antenna surface has been newly adjusted using digital photogrammetry, achieving a rms surface accuracy better than 130 μm. The pointing uncertainty is found to be less than 500 over the entire sky. We tested the new receiver system with multi-frequency observations in OTF mode. The aperture efficiencies are 43±1%, 42±1%, 37±1%, and 33±1%, the beam efficiencies are 45±2%, 48±2%, 46±2%, and 41±2% at 86, 98, 110, and 115 GHz, respectively.

참고문헌 (Reference)

1 Mangum, J. G., "The On-The-Fly Imaging Technique" 474 : 679-, 2007

2 Baars, J. W. M., "The Measurement of Large Anten-nas with Cosmic Radio Sources" 21 : 461-, 1973

3 이영웅, "TWO MOLECULAR CLOUDS WITH ANOMALOUS VELOCITIES IN THE GALACTIC ANTICENTER" 한국천문학회 47 (47): 319-325, 2014

4 Lee, S. -S., "Single-Dish Performance of KVN 21-m Radio Telescopes: Simultane-ous Observations at 22 and 43 GHz" 123 : 1398-, 2011

5 Koo, B. -C., "Shocked Molecular Gas in the Supernova Remnant HB 21" 552 : 175-, 2001

6 Weiland, J. L., "Seven-year Wilkinson Microwave Anisotropy Probe (WMAP)Observations: Planets and Celestial Calibration Sources" 192 : 19-, 2011

7 Lee, C., "Panel Adjust-ment of the TRAO 13.7-m Antenna Using Photogramme-try" 29 : 53-, 2014

8 Bon-ChulKoo, "PERFORMANCE OF THE SRAO 6-METER RADIO TELESCOPE" 한국천문학회 36 (36): 43-48, 2003

9 Sawada, T., "On-The-Fly Observing System of the Nobeyama 45-m and ASTE 10-m Telescopes" 60 : 445-, 2008

10 Loughnane, R. M., "Observations of HCN Hyper ne Line Anomalies towards Low-and High-mass Star-forming cores" 420 : 1367-, 2012

11 Cho, S. -H., "Observa-tions of SiO (v = 0; 1; 2) J = 3-2 and J = 2-1 Emission in Late-Type Stars" 115 : 277-, 1998

12 Joiner, J., "Modeling of Jupiter's Millimeter Wave Emission Utilizing Laboratory Measure-ments of Ammonia (NH3) Opacity" 96 : 17-, 1991

13 Cho, S. -H., "First Detection of the SiO(v = 3, J = 2-1)Maser Emission from χCygni" 657 : 482-, 2007

14 Roh, D. -G., "Characteristics of TRAO 14m Radio Telescope (1999)" 14 : 123-, 1999

15 Ladd, N., "Beam Size, Shape and E ciencies for the ATNF Mopra Radio Tele-scope at 86{115 GHz" 22 : 62-, 2005

16 Balanis, C. A., "Advanced Engineering Electromagnetics" John Wiley & Sons 1989

17 Erickson, N. R., "A Cryogenic Focal Plane Array for 85-115 GHz Using MMIC Preamplifiers" 47 : 2212-, 1999

18 Erickson, N. R., "A 15 Element Focal Plane Array for 100 GHz" 40 : 1-, 1992