• Journal of The Korean Astronomical Society
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• v.38 no.2
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• pp.103-106
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• 2005

The Submillimeter Array (SMA), a collaborative project of the Smithsonian Astrophysical Observatory (SAO) and the Academia Sinica Institute of Astronomy & Astrophysics (ASIAA), has begun operation on Mauna Kea in Hawaii. A total of eight 6-m radio telescopes comprise the array with currently working receiver bands at 230, 345, and 690 GHz. The array will have 8 receiver bands covering the frequency range of 180-900 GHz. The backend is flexible analog-digital correlator with a full bandwidth of 2GHz, which is very powerful to cover several line emissions simultaneously. The current status and future plans of the SMA are described with emphasis on Taiwanese efforts.

• The Bulletin of The Korean Astronomical Society
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• v.25 no.2
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• pp.21-21
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• 2000

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.39.2-39.2
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• 2015

The World Space Observatory Ultraviolet (WSO-UV) is the space mission that will grant access to the UV range in the post Hubble epoch. WSO-UV is equipped with instrumentation for imaging and spectroscopy and it is fully devoted to UV astronomy. In this talk, we outline the WSO-UV mission model and present the current status of the project. Also, the NEO observing mission SODA (System of Observation of Day-time Asteroids) is also presented.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.427-428
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• 1996

The Struve astrometric satellite which is being developed at Pulkovo Observatory in cooperation with Krasno-yarsk Institute of Applied Mechanics, S.I. Vavilov's State Optical Institute and some others space instrumentation institutes, will produce observations of a second epoch for the Hipparcos stars. The project is devoted to maintaining the Hipparcos coordinate system as well as extending it to a density of $\approx$ 100 stars per square degree. Possibilities of submilliarcsecond accuracy of observations with single aperture on-board telescopes are discussed. Requirements to the optical scheme and to the dynamic properties of the spacecraft are formulated. CCD and microchannel plates are discussed as a focal assembly detectors.

• Publications of The Korean Astronomical Society
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• v.32 no.1
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• pp.355-357
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• 2017

For future space IR missions, such as SPICA, it is crucial to establish an experimental method for evaluating the performance of mid-IR detectors. In particular, the wavelength dependence of the sensitivity is important but difficult to be measured properly. We are now preparing a testing system for mid-IR Si:As/Si:Sb detectors on SPICA. We have designed a cryogenic optical system in which IR signal light from a pinhole is collimated, passed through an optical filter, and focused onto a detector. With this system, we can measure the photoresponse of the detector for various IR light using optical filters with different wavelength properties. We have fabricated aluminum mirrors which are adopted to minimize thermal distortion effects and evaluated the surface figure errors. The total wavefront error of the optical system is $1.3{\mu}m$ RMS, which is small enough for the target wavelengths ($20-37{\mu}m$) of SPICA. The point spread function measured at a room temperature is consistent with that predicted by the simulation. We report the optical performance of the system at cryogenic temperatures.

• Journal of The Korean Astronomical Society
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• v.38 no.2
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• pp.109-112
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• 2005

We present the design, expected performance, and current status of the wide field near-infrared camera (OAOWFC) now being developed at Okayama Astrophysical Observatory, NAOJ, NINS. OAOWFC is a near-infrared survey telescope whose effective aperture is 91cm. It works at Y, J, H, and $K_s$ bands and is dedicated to the survey of long period variable stars in the Galactic plane. The field of view is $0.95 {\times} 0.95 deg^2$ which is covered by one HAWAII-2 RG detector of 2048 ${\times}$ 2048 pixels with the pixel size of $18.5 {\mu}m\;{\times}\;18.5{\mu}m$, that results in the sampling pitch of 1.6 arcsec/pixel. OAOWFC can sweep the area of $840 deg^2$ every 3 weeks, attaining a limiting magnitude of 13 in $K_s$ band. It allows us to observe long period variables embedded in the Galactic plane where interstellar extinction is severe in optical.

• Journal of The Korean Astronomical Society
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• v.35 no.4
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• pp.221-227
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• 2002

Cassegrain interface module (CIM) of the fiber-fed high resolution echelle spectrograph has been designed and manufactured for the 1.8 m reflector at the Bohynsan Optical Astronomy Observatory. We also constructed a long slit spectrograph attached to this CIM, which would replace the earlier rather inefficient medium dispersion spectrometer. We present detailed description for design and manufacturing concepts of the CIM which consists of a slit assembly, slit monitoring system, calibration lamp system and a long slit spectrograph, in order to provide how the overall system and each part. are constructed. The preliminary performance test carried out so far seems to indicate a successful result.

• Publications of The Korean Astronomical Society
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• v.16 no.1
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• pp.37-42
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• 2001

We developed an observation program for a 2K CCD camera, which was newly attached at the SOAO (Sobaeksan Optical Astronomy Observatory) 61cm telescope. The program was designed to control the telescope as well as the CCD camera and to monitor the CCD image quality, with very easy under the window-based graphical user interface (GUI). Furthermore, applying the automated differential photometric algorithm, we can obtain the instrumental magnitudes of several variable and comparison stars in real-time. Simultaneous photometry enables us to get precise differential magnitudes of variable stars even if the weather condition is not photometric. This new observation system has been using for many astronomical observations from September, 2001.

• Publications of The Korean Astronomical Society
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• v.33 no.2
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• pp.21-30
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• 2018

Formation processes of high-mass stars have been long-standing issues in astronomy and astrophysics. This is mainly because of major difficulties in observational studies such as a smaller number of high-mass young stellar objects (YSOs), larger distances, and more complex structures in young high-mass clusters compared with nearby low-mass isolated star-forming regions (SFRs), and extremely large opacity of interstellar dust except for centimeter to submillimeter wavelengths. High resolution and high sensitivity observations with Atacama Large Millimeter/Submillimeter Array (ALMA) at millimeter/submillimeter wavelengths will overcome these observational difficulties even for statistical studies with increasing number of high-mass YSO samples. This review will summarize recent progresses in high-mass star-formation studies with ALMA such as clumps and filaments in giant molecular cloud complexes and infrared dark clouds (IRDCs), protostellar disks and outflows in dense cores, chemistry, masers, and accretion bursts in high-mass SFRs.

• Publications of The Korean Astronomical Society
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• v.18 no.1
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• pp.81-86
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• 2003

We tested the characteristics of the newly made Long Slit Spectrograph (LSS) of the BOAO which replaced the Medium Dispersion Spectrograph (MDS) in the year of 2003. Performance test results on the spectrogram shift by gravity direction variation, slit illumination function, efficiency and the precision of the radial velocity measurements show the capabilities of the LSS are much improved in every respect comparing with those of the MDS.