• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.243-243
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• 1996

UBV observations have been made jointly at three observatories for the recent eclipse of the long period atmospheric eclipsing binary star Zeta Aur in 1995-6. Observations covered successfully the phases before, during, and after the eclipse enable us to determine the accurate time of mid-eclipse and the duration of the totality. The hypothesis of the expansion of the K supergiant has been tested and the positive conclusion may be derived.

• Publications of The Korean Astronomical Society
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• v.2 no.1
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• pp.39-46
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• 1985

We analyzed the reddening of 873 bright G and K stars from the DDO photometry in combination with MK spectral classes and (B-V) colors. About a quarter of the sample stars have DDO indices beyond the limits of DDO calibrations. To extend the reddening determination to all stars, we applied a scheme for reddening determination of field G and K stars by using the DDO calibrations (Janes 1977, 1979b) and MK-(B-V) relation of FitzGerald (1970).

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.85.3-85.3
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• 2019

Pulsating variable is a star whose luminosity changes through periodic pulsation. There are radiative and dynamical mechanisms hidden in periodic brightness changes, and the physical quantities related with the mechanisms are also expected to vary periodically. The purpose of this study is to investigate the periodic variations of the physical quantities of the ${\delta}$ Scuti type variable, V350 Peg by simultaneous photometry and spectroscopy. In this poster, we present preliminary results on apparent magnitude and radial velocity at the surface.

• Journal of Astronomy and Space Sciences
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• v.15 no.2
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• pp.277-289
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• 1998

We report V-(B - V) CCD Color Magnitude Diagrams (CMDs) for 23 southern Galactic globular clusters. Limiting magnitudes for each cluster are between 18 and 20 magnitudes in V. Most CMDs show subgiant starts, red giant stars, and horizontal branch stars. From the CMDs, we have determined the horizontal branch magnitudes, V(HB), reddenings, E(B - V), and distances of each cluster.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.51.2-51.2
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• 2017

As a result of our decade-long effort, we developed a new approach wherein small-aperture telescope powered by ingeniously designed narrow-band filter systems can have the capability to measure not only the heavy but also the lighter elemental abundances of the red-giant branch (RGB) and asymptotic-giant branch (AGB) stars in the globular clusters. Our novel approach can complement the intrinsic weakness of the results from the prestigious instruments, such as HST and the VLT. In our talk, we will present the multiple stellar populations of the RGB and the AGB stars in M5, as a pilot work.

• Journal of The Korean Astronomical Society
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• v.36 no.2
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• pp.49-54
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• 2003

CCD observations in V, I and H$\alpha$ for NGC 3389 are used to present photometry of 61 HII regions. Their positions, diameters and absolute luminosities have been determined. The luminosity and size distribution functions of the HII regions in NGC 3389 are discussed.

• Journal of The Korean Astronomical Society
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• v.30 no.1
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• pp.1-11
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• 1997

Near infrared JHK magnitudes are presented for two hundred two high proper motion stars. We have observed high proper motion stars in the near-infrared bands(JHK) using the COB detector on the Kitt Peak 1.3m, 2.1m and 4m telescopes. The observations and data reduction procedures are described. The infrared color magnitude diagram and color-color diagrams for the program stars are presented.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.84.2-84.2
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• 2014

We report the discovery of a new Milky Way globular cluster (GC) candidate in the Galactic plane. We found this object during our WISE survey of star clusters in the Milky Way. We derived physical parameters of this object using the 2MASS JHK photometry. The color-magnitude diagram of the resolved stars shows a well-developed red giant branch (RGB). We derived its reddening, distance and metallicity. These results indicate that it is probably an old globular cluster, located behind the Galactic disk.

• Journal of Astronomy and Space Sciences
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• v.29 no.2
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• pp.141-143
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• 2012

Some Algol-type interacting binary stars exhibit strange photometric variations that can be phase-dependent and/or secular. This paper discusses the possibility of explaining these observed variations as resulting from an accretion structure eclipsing one or both of the stars. Some previous studies are reviewed and suggestions for future work are made, including the prospective of incorporating data from the Kepler Observatory.

• Bulletin of the Korean Space Science Society
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• 1999.04a
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• pp.24-24
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• 1999

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