• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.94.2-94.2
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• 2014

After successful commissioning observations, IGRINS will soon begin its normal scientific operations on the 2.7m Harlan J. Smith telescope at the McDonald Observatory. We will present a working version of the IGRINS operation plan. A fraction of IGRINS guaranteed time will be devoted to a selection of strategic programs with legacy values, whereas the rest of the time will be used for normal programs. We will also describe the current status of the IGRINS data reduction pipeline package and its future development plan.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.41.4-42
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• 2015

The Immersion Grating Infrared Spectrograph (IGRINS) is the first of a new generation of infrared instruments with high sensitivity, high spectral resolution, and broad spectral grasp. IGRINS, a joint project of the University of Texas and the Korea Astronomy and Space Science Institute, designed and constructed by a team at UT, KASI, and Kyung Hee University, has been available to the Korean and Texas communities on the McDonald Observatory 2.7m telescope since 2014 September. On this modest-sized telescope, the instrument has 30 times the spectral grasp of CRIRES at the 8m VLT and is only slightly less sensitive. Already, Korean and UT astronomers have produced a raft of new results in star formation studies, investigations of the interstellar medium, and the nature of cool stars. Several programs are under way to detect and study the atmospheres of exoplanets. We will present highlights from the first 6 months of IGRINS operations and look at the future of IR spectroscopy both with IGRINS and with GMTNIRS, a UT/KASI/KHU instrument for the Giant Magellan Telescope.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.154.1-154.1
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• 2011

IGRINS (Immersion Grating Infrared Spectrometer) is a cross-dispersed high resolution near-infrared spectrograph whose primary disperser is a silicon immersion grating (SIG) and cross-dispersers are two volume phase holographic gratings (VPHG). IGRINS covers the full ranges of H and K astronomical wavelength bands at a single exposure with the spectral resolution of 40,000. The overall layout of the IGRINS Cryostat is a $960{\times}600{\times}380$ cubic millimeter rectangular box and the whole optical train is sitting on an $880{\times}520{\times}50\;mm^3$ rectangular Optical Bench. The total volume of the instrument has been revolutionarily reduced and remained compact for the spectral coverage and sensitivity of a high resolution spectrograph in infrared. We, in this presentation, introduce the design models, the structural and thermal analysis results of the mechanics and cryogenics of IGRINS.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.78.2-78.2
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• 2016

There are many telluric absorption lines which are laid on the science spectrum in ground based spectroscopic observations. In especial, the IR region spectra are considerably contaminated by telluric lines. Therefore, many scientists have a difficulty in removing the telluric effect. We thus tried removing telluric lines with IGRINS data by two methods. One is using the standard stellar spectrum as telluric lines. The other adopt calculated synthetic telluric spectrum. Here we present the results of test for precise removing telluric lines on IGRINS spectra.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.62.1-62.1
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• 2013

We present the Exposure Time Calculator of IGRINS (Immersion Grating Infrared Spectrograph). The noises of IGRINS and the simulated emission line can be calculated from the combination of Telluric background emission and absorptions, the emission and transmission of the telescope and instrument optics, and the dark noise and the read noise of the infrared arrays. For the atmospheric transmissions, we apply the simulated spectra depending on the Precipitable Water Vapor (PWV) values. In case of calculation of noises, the user needs to input the expected target magnitude, the weather conditions, and the desired exposure time. In addition to the simulated emission line, the parameters of rest wavelength, line-flux, Doppler shift and line-width are needed. The output would be the expected signal-to-noise for each spectral resolution element. The source-code of IGRINS-ETC v2.1.1 is available to be downloaded on the World Wide Web.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.150.1-150.1
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• 2011

한국천문연구원은 미국 텍사스 대학 및 경희대와 함께 2개의 적외선 고분산 분광기 프로젝트를 진행하고 있다. 2013년 완성을 목표로 진행하고 있는 IGRINS ((the Immersion GRating INfrared Spectrograph) 는 최종 설계를 완료하여 지난 8월 25일 최종 설계 검토 회의를 진행하였으며, 내년 상반기까지 제작, 하반기 실험실 정렬을 거쳐 2013년맥도날드 2.7미터 부착 시험 관측을 예정하고 있다. 한국이 참여하고 있는 거대망원경 GMT (Giant Magellan Telescope)의 제 1세대 관측기 기로 제안한 고분산 적외선 분광기 GMTNIRS 는 IGRINS의 성능에 J, L, M band 분광기능을 더한 것이다. 총 6개의 개념 설계 기기중 하나로 선정되어 지난 1년간 개념설계를 진행해 왔으며, 10월 3일 최종 개념 설계 검토 회의를 진행할 예정이다. 이 두 기기의 성능, 현재까지의 진행상황 그리고 앞으로의 계획에 대해 설명한다.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.84.1-84.1
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• 2013

We present a python-based data reduction pipeline for the Immersion GRating INfrared Spectrograph (IGRINS). IGRINS covers the complete H- and K-bands in a single exposure with a spectral resolving power of greater than 40,000. IGRINS is designed to be compatible with telescopes of diameters ranging from 2.7-m (the Harlan J. Smith telescope at McDonald Observatory) to 8-10m. Commissioning and initial operation will be on the 2.7-m telescope from late 2013. The pipeline package is a part of the IGRINS software and designed to be compatible with other package that maneuvers the spectrograph during the observation. This package provides high-quality spectra with minimal human intervention and the processes of order extraction, distortion correction, and wavelength calibration can be automatically carried out using the predefined functions (e.g. echellogram mapping and 2D transform). Since the IGRINS is a prototype of the Giant Magellan Telescope Near-Infrared Spectrometer (GMTNIRS), this pipeline will be extended to the GMTNIRS software.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.95-95
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• 2014

The mass measurement of neutron stars or black holes is of fundamental importance in our understanding of the evolution of massive stars and core-collapse supernova explosions as well as some exotic physics of the extreme conditions. Despite the importance, however, it's very difficult to measure mass of these objects directly. One way to do this, if they are in binary systems, to measure their binary motions (i.e., Doppler shifts) which can give us direct information on their mass. Recently many new highly-obscured massive X-ray binaries have been discovered by new hard X-ray satellites such as INTEGRAL and NuSTAR. The new highly-obscured massive X-ray binaries are faint in the optical, but bright in the infrared with many emission lines. Based on the near-infrared spectroscopy, one can first understand the nature of stellar companions to the compact objects, determining its spectral types and luminosity classes as well as mass losses and conditions of (potential) circumstellar material. Next, spectroscopic monitoring of these objects can be used to estimate the mass of compact objects via measuring the Doppler shifts of the lines. For the former, broad-band spectroscopy is essential; for the latter, high-resolution spectroscopy is critical. Therefore, IGRINS appears to be an ideal instrument to study them. An IGRINS survey of these new highly-obscured massive X-ray binaries can give us a rare opportunity to carry out population analyses for understanding the evolution of massive binary systems and formation of compact objects and their mass ranges. In this talk, we will present a sample near-infrared high resolution spectra of HMXB, IGR J19140+0951 and discuss about its spectral feature. These spectra are obtained on 13th July, 2014 from IGRINS commissioning run at McDonald 2.7m telescope. And at final, we will introduce the upgrade plan of IGRINS Operation Software (IGOS), to gather the input from IGRINS observer.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.41.1-41.1
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• 2010

IGRINS (the Immersion GRating Infrared Spectrograph) is a high resolution infrared spectrograph which is being developed by a collaboration of the University of Texas, the Korea Astronomy and Space Science Institute, and Kyung Hee University. The wavelength calibration unit of IGRINS will be situated between the telescope flange and IGRINS dewar. It will include Th-Ar hallow cathode lamp, optical elements, and gas absorption cell for the case that requires precise calibration (e.g., radial velocity observation). The system will also use a tungsten halogen lamp in an integrating sphere as a blackbody source for the flat-field imaging. IGRINS will be placed initially on the McDonald 2.7m Harlan J. Smith telescope and later on 4-8m class telescopes. We present an overview of the plan for the wavelength calibration sources and of the development process for the optical and mechanical design of the IGRINS calibration system.

• Bulletin of the Korean Space Science Society
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• 2011.04a
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• pp.31.2-31.2
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• 2011

IGRINS (Immersion GRating INfrared Spectrometer) is a high resolution wide-band infrared spectrograph developed by Korea Astronomy and Space Science Institute (KASI) and the University of Texas at Austin (UT). The slit-viewing camera is one of four re-imaging optics in IGRINS including the input relay optics and the H- and K- band spectrograph cameras. Consisting of five lenses and one Ks-band filter, the slit viewing camera relays the infrared image of $2'{\times}2'$ field around the slit to the detector focal plane. Since IGRINS is a cryogenic instrument, the lens barrel is designed to be optimized at the operating temperature of 130 K. The barrel design also aims to achieve easy alignment and assembly. We use radial springs and axial springs to support lenses and lens spacers against the gravity and thermal contraction. Total weight of the lens barrel is estimated to be 1.2 kg. Results from structural analysis are presented.