• Title/Summary/Keyword: solar imaging spectrograph

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Chromospheric oscillation signatures observed by the NST FISS

  • Kim, Yeon-Han;Cho, Il-Hyun;Bong, Su-Chan;Cho, Kyung-Suk;Yang, Heesu;Park, Young-Deuk
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.92.1-92.1
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    • 2013
  • In this study, we examined chromospheric oscillation signatures in two solar active regions, a limb active region and a sunspot with a light bridge, observed by the Fast Imaging Solar Spectrograph (FISS) of the 1.6m New Solar Telescope (NST) at Big Bear Solar Observatory. The FISS is a slit spectrograph with a fast imaging capability and can observe the solar chromosphere in $H{\alpha}$ and Ca II $8542{\AA}$ bands simultaneously with high spectral resolutions. After dark and flat correction, we compensated for image rotation at the Coude focus and made image alignment. We estimated Doppler shifts over active regions using the bisector method and investigated the temporal and spatial fluctuations of Doppler shifts for some selected cases. And we obtain the power map by using the Lomb-Scargle periodogram technique to examine the oscillation power at different features. Finally, we will discuss our results and implications.

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Observations of Solar Filaments with Fast Imaging Solar Spectrograph of the 1.6 meter New Solar Telescope at Big Bear Solar Observatory

  • Song, Dong-Uk;Park, Hyung-Min;Chae, Jong-Chul;Yang, Hee-Su;Park, Young-Deuk;Nah, Ja-Kyoung;Cho, Kyung-Suk;Jang, Bi-Ho;Ahn, Kwang-Su;Cao, Wenda;Goode, Philip R.
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.88.2-88.2
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    • 2011
  • Fast Imaging Solar Spectrograph (FISS) is an instrument developed by Seoul National University and Korea Astronomy and Space Science Institute and installed at the 1.6 meter New Solar Telescope of Big Bear Solar Observatory. Using this instrument, we observed solar filaments and analyzed the data focusing on determining the temperature and non-thermal velocity. We inferred the Doppler absorption widths of $H{\alpha}$ and Ca II 8542$\bar{A}$ lines from the line profiles using the cloud model. From these values, we separately determined temperature and non-thermal velocity. Our first result came from a solar filament observed on 2010 July 29th. Temperature inside a small selected region of this ranges from 4500K to 12000K and non-thermal velocity, from 3.5km/s to 7km/s. We also found temperature varied a lot with time. For example temperature at a fixed point varied from 8000K to 18000K for 40 minutes, displaying an oscillating pattern with a period of about 8 minutes and amplitude of about 2000K. We will also present new results from filaments observed in 2011 summer.

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Chromospheric Sunspot Oscillations in H-alpha and Ca II 8542A

  • Maurya, Ram Ajor
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.61.2-61.2
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    • 2013
  • We study chromospheric oscillations including umbral flashes and running penumbral waves in a sunspot using scanning spectroscopy in H-alpha and Ca II 8542A, with the Fast Imaging Solar Spectrograph (FISS) at the 1.6 meter New Solar Telescope at Big Bear Solar Observatory. A bisector method is applied to spectral observations to construct chromospheric Doppler velocity maps. Temporal sequence analysis of these shows enhanced high-frequency oscillations inside the sunspot umbra in both lines. Their peak frequency gradually decreases outward from the umbra. The oscillation power is found to be associated with magnetic-field strength and inclination, with different relationships in different frequency bands.

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Solar and Interplanetary Observations and Models in Korea (국내 우주환경 자료 보유 현황: 태양·행성간 공간)

  • Oh, Suyeon;Lee, Jin-Yi;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.160-177
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    • 2021
  • The Solar and Space Environment Division of the Korean Space Science Society investigated the use and possession of ground and satellite observations and models of solar and planetary data operated by domestic research institutes and universities. Based on the findings, we would like to introduce observational instruments, data, and models in solar and interplanetary fields in this paper to improve understanding and use of each data and explore opportunities for interdisciplinary research. The ground and satellite observations, which require a lot of investment, were mainly held by research institutes (National Meteorological Satellite Center, Polar Research Institute, Korean Space Weather, Korea Astronomy and Space Science Institute and KAIST Satellite Research Institute), and model development was overwhelmingly carried out at Kyung Hee University. In solar and interplanetary fields, we introduce Fast Imaging Solar Spectrograph (FISS), neutron monitors, and the analysis models [for the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA) and Hinode/X-Ray Telescope (XRT) observations] in nonequilibrium ionization state as representatives. Survey on solar and interplanetary fields can be downloaded from the website of the Korean Space Science Society (http://ksss.or.kr/). The paper makes know the importance of long-term and continuous management of space science-related materials, and hopes to contribute to enhancing the status of domestic space science data by utilizing locally produced data by various personnel participating in space science research.

2019 Total Solar Eclipse Expedition of KASI

  • Bong, Su-Chan;Yang, Heesu;Lee, Jae-Ok;Kim, Jinhyun;Jeon, Young-Beom;Jang, Bi-Ho;Seough, Jungjoon;Park, Young-Deuk
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.69.2-69.2
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    • 2020
  • Korea Astronomy and Space Science Institute (KASI) is developing a coronagraph to measure the coronal electron density, temperature, and speed utilizing spectral change of the K-corona around 400 nm. However, near UV light is more affected by atmospheric effect on the ground than visible light. For the total solar eclipse on July 2 2019, KASI organized an expedition team to test the possibility of the similar measurement scheme in the visible light. The observation site was in Las Flores, San Juan, Argentina. We built an imaging spectrograph using micro lenslet array and grism, named Coronal Integral Field Spectrograph (CorIFS). In addition, images of white light corona, wide field background, and all sky were taken with various camera settings. We present the preliminary results of the expedition.

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