• Title/Summary/Keyword: infrared%3A telescope

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The CTIO 4m UBVI & $H{\alpha}$ photometry and spatial variation of the reddening law in the ${\eta}$ Carina nebula

  • Hur, Hyeonoh;Sung, Hwan Kyung;Lim, Beomdu;Chun, Moo-Young;Sohn, Sangmo Tony
    • The Bulletin of The Korean Astronomical Society
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    • v.40 no.1
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    • pp.71.3-71.3
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    • 2015
  • Deep UBVI and $H{\alpha}$ photometry of the ${\eta}$ Carina nebula, one of the brightest nebulae on the sky, was obtained with the CTIO 4m telescope and MOSAIC II CCD Camera to determine the initial mass function down to low-mass (~1 M¤) stars. We modified the spatial variation coefficients in transformation relations of the MOSAIC II CCD. From the cross-identification of optical sources with previous surveys in X-ray, near-infrared, and mid-infrared, a clear PMS sequence is revealed in the optical color-magnitude diagrams down to V=23 mag. Our previous SSO 1m UBVI data for Trumpler 14 (Tr 14) and Trumpler 16 (Tr 16) region, and additional SSO 1m UBVI data for Trumpler 15 (Tr 15) region were combined with the CTIO 4m data to re-examine the reddening law and distance of the young open clusters in the ${\eta}$ Carina nebula. From the new photometric data for Tr 15 region, we report that RV[=AV/E(B-V)], the total-to-selective extinction ratio, decreases from southern part of the nebula (Tr 14 and Tr 16) to northern part (Tr 15) in our field of view.

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On Orbit Data Analysis About the Passive Cooling of MIRIS, a Compact Space Infrared Telescope

  • Lee, Duk-Hang;Moon, Bongkon;Jeong, Woong-Seob;Pyo, Jeonghyun;Lee, Chol;Kim, Son-Goo;Park, Youngsik;Lee, Dae-Hee;Park, Sung-Joon;Kim, Il-Joong;Park, Won-Kee;Seon, Kwang-Il;Nam, Uk-Won;Cha, Sang-Mok;Park, Kwijong;Park, Jang-Hyun;Yuk, In-Soo;Ree, Chang Hee;Jin, Ho;Yang, Sun Choel;Park, Hong-Young;Shin, Ku-Whan;Suh, Jeong-Ki;Rhee, Seung-Wu;Park, Jong-Oh;Lee, Hyung Mok;Matsumoto, Toshio;Han, Wonyong
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.50.1-50.1
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    • 2014
  • The Multi-purpose InfraRed Imaging System (MIRIS) is the main payload of Science and Technology Satellite 3 (STSAT-3), which was launched onboard Dnepr rocket from Russian Yasny Launch Base in November 2013. The MIRIS is an infrared (IR) camera, and the telescope has to be cooled down to below 200K in order to reduce thermal background noise. For the effective cooling and low-power consumption, we applied passive cooling method to the thermal design of the MIRIS. We also conducted thermal analysis and tested for the passive cooling before the launch of STSAT-3. After the launch, we have received State-of-Health (SOH) data from the satellite on orbit, including temperature monitoring results. It is important that the temperature of the telescope was shown to be cooled down to below 200K. In this paper, we present both the temperature data of the MIRIS on orbit and the thermal analysis results in the laboratory. We also compare these results and discuss the verification of the passive cooling.

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SPICA Near-Infrared Instrument, FPC and its Science

  • Jeong, Woong-Seob;Matsumoto, Toshio;Lee, Dae-Hee;Ree, Chang-Hee;Park, Young-Sik;Moon, Bong-Kon;Park, Sung-Joon;Pyo, Jeong-Hyun;Han, Won-Yong;Lee, Hyung-Mok;Im, Myung-Shin;Koo, Bon-Chul;Ishiguro, Masateru;Woo, Jong-Hak
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.76-76
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    • 2011
  • The SPICA (SPace Infrared Telescope for Cosmology & Astrophysics) project is a next-generation astronomical mission optimized for mid- and far-infrared observation with a cryogenically cooled 3m-class telescope. Due to its high angular resolution and unprecedented sensitivity, SPICA will enable us to resolve many key issues from the star-formation history of the universe to the planetary formation. As an international collaboration, KASI proposed the near-infrared instrument which is composed of two parts; (1) science observation with the capability of imaging and spectroscopy covering $0.7{\mu}m$ to $5{\mu}m$ (FPC-S) (2) fine guiding to stabilize and improve the attitude (FPC-G). Here, we present the current status of SPICA/FPC.

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OKAYAMA ASTROPHYSICAL OBSERVATORY WIDE-FIELD CAMERA

  • YANAGISAWA KENSHI
    • 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.

Intracluster Light Study of the Distant Galaxy Cluster SPT2106-5844 at z=1.132 with Hubble Space Telescope Infrared Imaging Data

  • Joo, Hyungjin;Jee, Myungkook James;Ko, Jongwan
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.76.3-76.3
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    • 2019
  • Intracluster stars are believed to be gravitationally bound to a galaxy cluster, however, not to individual cluster galaxies. Their presence is observed as diffuse light typically in the central region extended from the brightest cluster galaxy. The diffuse light, often referred to as intracluster light (ICL), is difficult to quantify in distant high-redshift galaxy clusters because of the significant surface brightness dimming although ICL observations in high-redshift clusters provide powerful constraints on the origin of intracluster stars. In this poster, we present ICL study of the distant galaxy cluster SPT2106-5844 at z=1.132 with Hubble Space Telescope IR imaging data. With careful control of systematics, we successfully quantify the total amount of the ICL, measure the color profile, and obtain its two-dimensional distribution. Our measurement of the high abundance of the intracluster stars in this young cluster favors the ICL formation scenario, wherein production of intracluster stars are predominantly associated with the BCG formation.

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Developments of the Wide Wavelength Range Polarimeter of the Domeless Solar Telescope at the Hida Observatory

  • Anan, Tetsu;Ichimoto, Kiyoshi;Oi, Akihito;Ueno, Satoru;Kimura, Goichi;Nakatani, Yoshikazu
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.86.1-86.1
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    • 2011
  • We are developing a new universal spectropolarimeter on the Domeless Solar Telescope (DST) at the Hida Observatory to realize precise spectropolarimetric observations in a wide range of wavelength in visible and near infrared. The system aims to open a new window of plasma diagnostics by using Zeeman effect, Hanle effect, Stark effect, impact polarization, and atomic polarization for measuring the external magnetic field, electric field, or an anisotropy in the excitation of the atoms. The polarimeter is a successor of formerly developed polarimeter on DST, which make possible to observe a polarization in a photospheric spectral line with polarimetric accuracy of 10-2 (Kiyohara et al. 2004). The new system consists of a 60cm aperture vacuum telescope, a high dispersion vacuum spectrograph, polarization modulator / analyzer composed of a rotating waveplate whose retardation is constant for a wide range of wavelength and Wallaston prism, and a fast and large format CCD camera or IR camera. Spectral images in both orthogonal polarizations are taken simultaneously with a frame rate of ~20Hz while the waveplate rotates continuously in a rate of 1rev./sec. Thus It takes 5 ~ 60 sec to observe polarization with accuracy of 10-3 in a wide wavelength range (400 - 1100nm). We also examined a polarimetric model of the telescope with accuracy of 10-3 to calibrate instrumental polarization on some wavelengths. In this talk, I will focus on the performance of the instrument.

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A MULTI-WAVELENGTH STUDY OF 30 DORADUS COMPLEX IN THE LARGE MAGELLANIC CLOUD

  • Kim, Sung-Eun
    • Journal of The Korean Astronomical Society
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    • v.38 no.3
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    • pp.365-370
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    • 2005
  • We have made a multi-wavelength study of the X-ray bright giant shell complex 30 Doradus in the Large Magellanic Cloud (LMC). This is the one of the largest H II complexes in the Local Group. The Australia Telescope Compact Array (ATCA) and the Parkes 64-m single dish observations reveal that the distribution and internal motions of H I gas show the effects of fast stellar winds and supernova blasts. The hot emitting gas within the 30 Doradus complex and the entire giant H II complex are encompassed by an expanding H I shell. We investigate the dynamical age of this H I shell and compare to the age of starbursts occurred in the 30 Doradus nebula using the radiative transfer model and the infrared properties.

Near-infrared Spectroscopy of Young Stellar Objects around the Supernova Remnant G54.1+0.3

  • Kim, Hyun-Jeong;Koo, Bon-Chul;Moon, Dae-Sik;Lee, Sang-Gak
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.1
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    • pp.68.2-68.2
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    • 2010
  • We present near-infrared (NIR) spectra of 6 young stellar objects (YSOs) around the supernova remnant G54.1+0.3 obtained with TripleSpec, a slit-based NIR cross-dispersion echelle spectrograph on th 5-m Palomar Hale telescope covering the entire NIR atmospheric window of 1-2.4 micron. These YSOs, whose formation was possibly triggered by the progenitor of G54.1+0.3, show significant mid-infrared (MIR) excess and have been proposed to be late O- and early B-type YSOs based on their spectral energy distribution. Our TripleSpec observations reveal the existence of strong H and He I lines, consistent with the previous interpretation of their spectral types, while the absence of Br-gamma emission line indicates that the YSOs do not have a nearby circumstellar disk. We discuss the relation between these YSOs and G54.1+0.3 based on the TripleSpec data and previous photometric data as well.

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COSMIC STAR FORMATION HISTORY AND AGN EVOLUTION NEAR AND FAR: AKARI REVEALS BOTH

  • Goto, Tomotsugu;AKARI NEP team, AKARI NEP team;AKARI all sky survey team, AKARI all sky survey team
    • Publications of The Korean Astronomical Society
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    • v.27 no.4
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    • pp.347-352
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    • 2012
  • Understanding infrared (IR) luminosity is fundamental to understanding the cosmic star formation history and AGN evolution, since their most intense stages are often obscured by dust. Japanese infrared satellite, AKARI, provided unique data sets to probe this both at low and high redshifts. The AKARI performed an all sky survey in 6 IR bands (9, 18, 65, 90, 140, and $160{\mu}m$) with 3-10 times better sensitivity than IRAS, covering the crucial far-IR wavelengths across the peak of the dust emission. Combined with a better spatial resolution, AKARI can measure the total infrared luminosity ($L_{TIR}$) of individual galaxies much more precisely, and thus, the total infrared luminosity density of the local Universe. In the AKARI NEP deep field, we construct restframe $8{\mu}m$, $12{\mu}m$, and total infrared (TIR) luminosity functions (LFs) at 0.15 < z < 2.2 using 4,128 infrared sources. A continuous filter coverage in the mid-IR wavelength (2.4, 3.2, 4.1, 7, 9, 11, 15, 18, and $24{\mu}m$) by the AKARI satellite allows us to estimate restframe $8{\mu}m$ and $12{\mu}m$ luminosities without using a large extrapolation based on a SED fit, which was the largest uncertainty in previous work. By combining these two results, we reveal dust-hidden cosmic star formation history and AGN evolution from z = 0 to z = 2.2, all probed by the AKARI satellite.

A catalog of infrared supernova remnants in the Large Magellanic Cloud

  • Seok, Ji-Yeon;Koo, Bon-Chul
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.104.1-104.1
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    • 2011
  • We present a catalog of infrared supernova remnants (SNRs) in the Large Magellanic Cloud (LMC). We have searched the Spitzer archival data for infrared counterparts to all 45 known SNRs in the LMC, and identified 21 which is 47% of the known SNRs. Seven of them are newly detected: SNR 0450-70.9, SNR in N4, N103B, DEM L241, DEM L249, DEM L316A, and DEM L316B. All newly discovered SNRs show emission at several IRAC 3.4, 4.5, 5.8, and 8.0 micron bands and/or MIPS 24 and 70 micron bands. Most SNRs show shell structures. We derive infrared fluxes of these newly detected SNRs. The catalog contains general information of each SNR such as location, age, and SN type together with AKARI and/or Spitzer fluxes. For the entire SNR sample, we examine their infrared colors and the possible correlation of the infrared fluxes with the fluxes at other wavelengths. For the newly detected SNRs except the SNR in N4, we also performed follow-up imaging observations of [Fe II] 1.644 micron line using IRIS2 mounted on the Anglo Australian Telescope. Three out of six SNRs show [Fe II] emission corresponding to their infrared shells. [Fe II] knots are also detected in N103B which show good spatial correlation to infrared emission seen at Spitzer images as well as knotty $H{\alpha}$ emission. We investigate the characteristics and origin of the infrared emission in individual SNRs, and discuss the environmental and evolutionary effects.

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