We improved the antenna efficiency of the Taeduk Radio Astronomy Observatory (TRAO) 13.7-m radio telescope by adjusting the antenna panels based on digital photogrammetric measurements. First of all, we measured the surface accuracy of the main reflector of this antenna at three elevation angles of 35°, 45°, and 60°. We performed a total of four sets of the photogrammetric measurements and panel adjustments. When adjusting the panels, we positioned the antenna to the zenith and applied the measured data sets at the elevation of 45°. We found that the antenna surface accuracy has been improved by a factor of ~ 3 times after the final adjustment in comparison with the value before the adjustments. And we also found that the antenna surface accuracy tended to be slightly better at the elevation angles of 35° and 60° than that at the elevation angle of 45°. After the final panel adjustment, the aperture and beam efficiencies of the telescope have has been improved from 35% to 44%, and from 41% to 51%, respectively.

We present a multi-dimensional reduction method of the surveyed cube database obtained using a single- dish radio telescope in Taeduk Radio Astronomy Observatory (TRAO). The multibeam receiver system installed at the 14 m telescope in TRAO was not optimized at the initial stage, though it became more stabilized in the following season. We conducted a Galactic Plane survey using the multibeam receiver system. We show that the noise level of the first part of the survey was higher than expected, and a special reduction process seemed to be definitely required. Along with a brief review of classical methods, a multi-dimensional method of reduction is introduced; It is found that the ‘background’ task within IRAF (Image Reduction and Analysis Facility) can be applied to all three directions of the cube database. Various statistics of reduction results is tested using several IRAF tasks. The rms value of raw survey data is 0.241 K, and after primitive baseline subtraction and elimination of bad channel sections, the rms value turned out to be 0.210 K. After the one-dimensional reduction using ‘background’ task, the rms value is estimated to be 0.176 K. The average rms of the final reduced image is 0.137 K. Thus, the image quality is found to be improved about 43% using the new reduction method.

We present results of a test-study of the large-scale survey using the multi-beam receiver system recently installed on the 14 m telescope at Taeduk Radio Astronomy Observatory (TRAO). We have tested several modes of mapping, and found suitable (time-saving) mapping parameters of 'ON-SOURCE' = 8, 'OFF-SOURCE' = 1 when using 'RPT' = 3 as a position-switching mode. We observed 504 spectra towards the NGC 7538, a star forming molecular cloud in the transition of J = 1 - 0 of 12CO . From the Outer Galaxy Survey database (Heyer et al., 1998) we obtained 504 spectra for the same region. We compared integrated intensities, line profiles of two databases, and found that they are consistent to each other. From the intensity ratio of these two databases we also found that the value of forward spillover scattering of the TRAO telescope system is 0.58.

A survey project of TRAO with the fifteen beam array receiver system is presented. A multibeam array receiver system has been purchased from FCRAO, and is being installed on TRAO 14m telescope. The target region of the survey is from ι=120° ~137°, b=-1°~+1°, and velocity resolution would be 1 km/sec after smoothing from the original resolution of 0.64km s-1in the transition of J = 1-0 of 13CO The survey region is a part of the 12CO Outer Galaxy Survey(OGS), and would be an extension of the Bell Laboratories 13CO Galactic Plane Survey. By combining with the existing 12CO database of the Outer Galaxy Survey, we will derive physical properties of identified molecular clouds and will conduct and statistical analysis of the Outer Galalxy molecular clouds. Reduction process and analysis methods will be introduced.