• Title/Summary/Keyword: 보현산

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LIGHT CURVE ANALYSIS OF CONTACT BINARY SYSTEM V523 CASSIOPEIAE (접촉쌍성 V523 CAS의 광도곡선 분석)

  • 김진희;정장해
    • Journal of Astronomy and Space Sciences
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    • v.19 no.4
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    • pp.263-272
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    • 2002
  • A total of 616 observations (308 in B, 308 in V) to. V523 Cas was made on three nights from October 19 to 21 in 1999 using the 1.8m telescope with 2K CCD camera of the Bohyunsan Optical Astronomy Observatory of KAO. With our data we constructed the BV light curves and determined 4 times of minimum light. We also obtained physical parameters of the system by combined analysis of both light and radial velocity curves using the Wilson-Devinney code.

고분산 분광 관측을 통한 공생별 AG Draconis와 EG Andromedae의 특성 연구

  • Kim, Su-Hyeon;Yun, Tae-Seok;Lee, Byeong-Cheol
    • Bulletin of the Korean Space Science Society
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    • 2010.04a
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    • pp.32.2-32.2
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    • 2010
  • 보현산 천문대 1.8-m 망원경과 고분산 에셀 분광기 BOES(BOao Echelle Spectrograph)를 이용해 관측한 다년간의 공생별 관측자료 중 AG Draconis와 EG Andromedae의 방출선들을 분석하여 그 분광학적 특성을 밝혀내고자 한다. 수소 Balmer 계열 방출선들과 He I $\lambda5875{\AA}$, He I $\lambda6678{\AA}$, He I $\lambda7065{\AA}$, He II $\lambda4686{\AA}$, O VI $\lambda6030{\AA}$, O VI $\lambda7088{\AA}$ 방출선들의 단 장기 변화와 특징을 살펴보며, 그 방출선들 간의 비교를 통해 두 공생별의 특성 변화에 대해 알아본다.

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A Brief Overview of the KASI-Deep Rolling Imaging Fast-optics Telescope(K-DRIFT): Exploring the Low-surface-brightness(LSB) Universe

  • Ko, Jongwan
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.55.4-55.4
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    • 2021
  • 한국천문연구원에서는 낮은 표면밝기(Low Surface Brightness; LSB)의 천체를 효율적으로 관측할 수 있는 소형(〉30cm) 광시야(〉1°×1°) 광학망원경 및 관측기술 개발을 통한 은하형성 규명 연구를 수행 중에 있다. 이번에 개발한 K-DRIFT pathfinder는 비축 자유곡면 3반사 망원경 시스템(Linear Astigmatism Free-Three Mirror System; LAF-TMS)으로 넓은 시야에서 고품질의 이미지를 효율적으로 얻을 수 있는 광학 설계를 적용하고, 배경 값 변동 요인을 분석하여 가까운 우주의 LSB 천체 관측에 최적화될 수 있도록 하였다. 이번 특별세션에서는 '왜 LSB 우주 탐사를 하고, K-DRIFT를 개발하는지?'에 대해서 소개하고, K-DRIFT pathfinder의 개발 과정, 보현산 천문대에서의 시험관측 결과 소개와 함께, LSB 천체 연구를 위한 맞춤형 시뮬레이션 개발 및 수행 내용을 소개한다.

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A Search for New Variable Stars in the Open Cluster NGC 129 using a Small Telescope (소형망원경을 이용한 산개성단 NGC 129 영역의 변광성 탐사)

  • Lee, Eun-Jung;Jeon, Young-Beom;Lee, Ho;Park, Hong-Suh
    • Journal of the Korean earth science society
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    • v.28 no.1
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    • pp.87-104
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    • 2007
  • As part of the SPVS (Short-Period Variability Survey) which is a wide-field $(90'{\times}60')$ photometric monitering program at Bohyunsan Optical Astronomy (BOAO), we performed V band time-series CCD photometric observations ofthe young open cluster NGC 129 for 11 nights between October 12, 2004 and November 3, 2005 using the 155mm refractor equipped with $3K{\times}2K$ CCD camera. From the observation we obtained 2400 V band CCD frames and color-magnitude diagram of the cluster. To transform instrumental magnitude to standard magnitude, we applied ensemble normalization technique to all observed time-series data. After the photometric reduction process, we examined variations of 9537 stars. As a result, sixty six of the new variable stars were discovered. To determine the periods of the sevariables, we used DFT(Discrete Fourier Transform) and phase-matching technique. According to light curve shape, period, amplitude and the position on a C-M diagram, we classified these variables as 9 SPB type, 9 ${\delta}$ Scuti type, 29 eclipsing, 17 long term variables. However, two of them were not classified. From this study, we learned that small telescopes could be a very useful tool to observe variable stars in the open cluster in survey program.

The Vascular Plants in Mt. Bohyeon, Gyeongbuk, Korea (보현산(경북)의 관속식물상 연구)

  • Park, Kyu Tae;Choi, Kyoung Su;Son, Ogyeong;Lee, Eun Mi;Kim, Hae Sik;Boo, Da Un;Park, SeonJoo
    • Korean Journal of Plant Resources
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    • v.28 no.2
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    • pp.193-216
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    • 2015
  • This study was carried out to investigate the vascular plants of Mt. Bohyeon (Gyeongbuk). The vascular plants were collected 22 times and summarized as 589 taxa, including 105 families, 327 genera, 522 species, 11 subspecies, 48 varieties and 8 forms respectively. Among them, 13 Korean endemics, 10 red list of vascular plants, 2 endangered plants and 83 specially designated plants by the Ministry of Environment were included respectively. The naturalized plants were 37 taxa and the naturalized ratio was 6.41 of 589 taxa. Usage of 589 taxa were consists of 240 taxa (40.1%) of edible plants, 205 taxa (34.2%) of medicinal plants, 62 taxa (10.3%) of ornamental plants, 213 taxa (35.6%) of pasture plants, 15 taxa (2.5%) of timber plants, 8 taxa (1.3%) of fiberplants, and 3 taxa (0.5%) of industrial plants.

Ionospheric and Upper Atmospheric Observations in Korea (국내 우주환경 자료 보유 현황: 전리권/고층대기)

  • Lee, Changsup;Lee, Woo Kyoung;Division of Solar and Space Environment of KSSS,
    • Journal of Space Technology and Applications
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    • v.1 no.2
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    • pp.199-216
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    • 2021
  • In 2020, the solar and space environment division at the Korea Space Science Society surveyed the status of data archives in solar physics, magnetosphere, and ionosphere/upper atmosphere in Korea to promote broader utilization of the data and research collaboration. The survey includes ground- and satellite-based instruments and developing models by research institutes and universities in Korea. Based on the survey results, this study reports the status of the ground-based instruments, data products in the ionosphere and upper atmosphere, and documentation of them. The ground-based instruments operated by the Korea Polar Research Institute and Korea Astronomy and Space Science Institute include ionosonde, Fabry-Perot interferometer in Arctic Dasan stations, Antarctic King Sejong/Jang Bogo stations, and an all-sky camera, VHF radar in Korea. We also provide information on total electron content and scintillation observations derived from the Global Navigation Satellite System (GNSS) station networks in Korea. All data are available via the webpage, FTP, or by request. Information on ionospheric data and models is available at http://ksss.or.kr. We hope that this report will increase data accessibility and encourage the research community to engage in the establishment of a new Space Science Data Ecosystem, which supports archiving, searching, analyzing, and sharing the data with diverse communities, including educators, industries, and the public as wells as the research scientist.

A Comparison between Infrared and Visible Light Curves of Short Period Variables

  • Lim, Jihye;Sohn, Jungjoo
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.2
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    • pp.58.1-58.1
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    • 2015
  • 단주기 변광성들의 적외선 광도곡선이 가시광선 광도 곡선과 어떠한 차이가 있는지 알아보기 위해 주기가 하루 이내로 짧은 다양한 유형의 변광성을 대상으로 보현산 천문대의 1.8m 반사망원경과 적외선검출기(KASINICS)를 이용한 J($1.25{\mu}m$), H($1.64{\mu}m$), K($2.15{\mu}m$)필터 관측을 수행하였다. 관측 대상은 맥동변광성으로 분류되는 BO Lyn외 2개 대상, 격변변광성으로 분류되는 RX And외 3개 대상, 그리고 식변광성으로 분류되는 V1007 Cas외 1개 대상이다. IRAF를 이용한 전처리 및 구경 측광을 실시하여 각 필터별 적외선 광도곡선을 얻었다. 이를 통해 현재 각 분류 대상별 주기분석과 여러 해 동안 관측한 자료를 이용하여 각 대상들의 장주기에서의 변광 요인 유무도 확인하여 가시광선 광도곡선과의 비교 분석 연구를 수행하고 있다. 격변변광성의 경우 가시광 광도 곡선이 주로 강착원반의 더 뜨거운 내부고리와 대기에 의한 것인 반면 적외선 광도 곡선은 동반성과 차가운 강착원반에 의한 것이라 여겨지며, 맥동변광성과 식변광성의 경우도 가시광선과 적외선이 서로 다른 깊이를 보게 될 것이므로 파장대별 최대 밝기 위치와 광도 윤곽에서의 차이가 기대된다.

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THE SLOPE OF ΔM LIGHT CURVE DEPENDING UPON THE ITS LOCATION IN CCD FRAME (CCD 이미지 상의 그 위치와 ΔM 광도곡선의 기울기)

  • 정장해;임인성
    • Journal of Astronomy and Space Sciences
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    • v.19 no.1
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    • pp.39-46
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    • 2002
  • BV observations for V523 Cas were performed with 1.8m telescope and 2K CCD camera at Bohyunsan Optical Astronomy Observatory, Korea, on October 27, 1999. ${\Delta}m$ light curves for 11 comparison objects were made. It was found that their light curve slopes are different each other. Factor analysis for items of slope, (b-v) , magnitude, X pixel, and Y pixel results that there is strong correlation between the slope and the location (X,Y). It might be due to problems of CCD cooling system.

CHARACTERISTICS OF THE BOAO 2K CCD CAMERA (보현산천문대 2K CCD 카메라의 특성)

  • PARK BYEONG-GON;CHUN MOO-YOUNG;YUK IN-SOO;SEONG HYEON-CHEOL
    • Publications of The Korean Astronomical Society
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    • v.16 no.1
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    • pp.31-36
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    • 2001
  • We present the characteristics of the 2K CCD camera at the Bohyunsan Optical Astronomy Observatory of the Korea Astronomy Observatory at the time of its development. The purpose of this paper is to support the observers who may need detailed information on the characteristics of the camera and to provide helpful information on the optimization' of a CCD camera for those who try to develop their own camera. The 2K CCD camera was optimized to have a gain of $1.8e^-/ADU$ and a read out noise of $7e^-$ from an experiment using radioactive $^{55}Fe$ X-ray source. The charge transfer efficiency was measured as 0.9999976 for serial and 0.9999942 for parallel direction, which means $0.5\%$ charge loss along the serial direction and $1.2\%$ along the parallel direction across the chip. The quantum efficiency of the camera was measured from an experiment using a homogeneous light source consisting of a halogen lamp and an integrating sphere with a monochromator. The resulting quantum efficiency of the camera peaked at the wavelength range 600-700 nm with the value of $\~0.89$.

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CONSTRUCTION OF THE BOAO ECHELLE SPECTROGRAPH (BOES) (보현산천문대 고분산 에셀분광기(BOES) 제작)

  • KIM KANG-MIN;JANG JEONG GYUN;CHUN MOO-YOUNG;PARK BYEONG-GON;HYUNG SIEK;HAN INWOO;YOON TAE SEOG;VOGT STEVEN S.
    • Publications of The Korean Astronomical Society
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    • v.15 no.spc1
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    • pp.119-126
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    • 2000
  • The BOES (BOAO Echelle Spectrograph), a fiber-fed echelle spectrograph of the BOAO 1.8 m telescope, has been designed and now is being manufactured. The BOES follows a white pupil design collimated with two off-axis parabolic mirrors. The 136mm collimating beam leaving the 41.59 grooves/mm R4 echelle grating is refocused near the narrow folding mirror. Through the two cross-disperser prisms and $\phi250 mm(f/1.5)$ transmission camera, the beam images on EEV $2k\times4k$ CCD. The BOES can take the wavelength range of 3700 to $10100{\AA}$ at a single spot with spectral resolution R = 20000 to 40000 depending on the fiber set employed. We describe the key sciences and performance, current status of construction, and future plan of the BOES.

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