• 제목/요약/키워드: Mid-infrared

검색결과 274건 처리시간 0.025초

Mid-IR Luminosity Functions of Local Galaxies in the North Ecliptic Pole Field

  • Kim, Seong Jin;Lee, Hyung Mok;Jeong, Woong-Seob
    • 천문학회보
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    • 제40권1호
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    • pp.72.3-72.3
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    • 2015
  • We present the mid-infrared (MIR) luminosity function (LF) of local (z < 0.3) star forming (SF) galaxies based on the AKARI's NEP-Wide Survey data. We utilized a combination of the NEP-Wide point source catalogue containing a large number (114,000) of infrared (IR) sources distributed over the wide (5.4 sq. deg) field and spectroscopic redshift (z) data for 1790 selected targets obtained by optical follow-up surveys with MMT/Hectospec and WIYN/Hydra. The AKARI's continuous $2{\sim}24{\mu}m$ wavelength coverage and the spectroscopic redshifts for sample galaxies enable us to derive accurate spectral energy distributions (SEDs) in the mid-infrared. We carried out SED-fit analysis and employed 1/Vmax method to derive the mid-IR (e.g., $8{\mu}m$, $12{\mu}m$, and $15{\mu}m$ rest-frame) luminosity functions. Our results for local galaxies from the NEP region generally consistent with various previous works for other fields over wide luminosity ranges. The comparison with the results of the NEP-Deep data implies the luminosity evolution from higher redshifts towards the present epoch. We attempted to fit our derived LFs to the double power-laws and present the resulting power indices. We also examined the correlation between mid-IR luminosity and total IR luminosity.

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중적외선 영상 잡음 감소를 위한 SW 필터의 설계 및 구현 (Design and Software Implementation of Noise Reduction Filter for Mid-wave Infrared Images)

  • 박현성;김정호;이성호
    • 한국군사과학기술학회지
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    • 제19권4호
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    • pp.500-507
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    • 2016
  • In order to increase the survivability of combatant ship, measuring and analyzing the infrared radiation is important. Consequently, providing analysis report is also important for the progress of the new combatant ship design. This paper proposes a design and software implementation of filtering for the noise reduction of mid-wave IR camera image. We reduced the total test cost by using the suggested software filtering technique instead of hardware replacement or re-calibration. In addition, we enhanced the accuracy of analysis results by adjusting the parameters of software filtering according to the results of filtered image.

Quantitative Measurement of Ethane Using Mid-infrared Cavity Ring-down Spectroscopy

  • Yonghee Kim;Byung Jae Chun;Lim Lee;Kwang-Hoon Ko;Seung-Kyu Park;Taek-Soo Kim;Hyunmin Park
    • Current Optics and Photonics
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    • 제7권4호
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    • pp.457-462
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    • 2023
  • Quantitative measurement of trace ethane is important in environmental science and biomedical applications. For these applications, we typically require a few tens of part-per-trillion level measurement sensitivity. To measure trace-level ethane, we constructed a cavity ring-down spectroscopy setup in the 3.37 ㎛ mid-infrared wavelength range, which is applicable to multi-species chemical analysis. We demonstrated that the detection limit of ethane is approximately 300 parts per trillion, and the measured concentration is in agreement with the amounts of the injected sample. We expect that these results can be applied to the chemical analysis of ethane and applications such as breath test equipment.

칼날 주사방식을 이용한 중적외선 렌즈의 변조전달함수 측정 장치 (Modulation Transfer Function System for a Mid-infrared Lens by Knife-edge Scanning Technique)

  • 송세용;조재흥;홍성목;이회윤;이윤우
    • 한국광학회지
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    • 제22권1호
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    • pp.16-22
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    • 2011
  • 중적외선 결상용 실리콘 렌즈의 변조전달함수(MTF)를 칼날 주사방식으로 측정하는 적외선 MTF 측정장치를 구성하였다. 이를 위하여 반달형 칼날 물체를 사용하여 초점거리 50 mm, F/4인 실리콘 렌즈에 대한 중적외선 파장대인 $3{\sim}5\;{\mu}m$에서의 축상 자오 방향에 대한 MTF를 측정하였다. 이 때 무한 물체를 만들기 위해서 초점거리가 2.545 m인 비축 포물 반사경을 사용하였다. 측정한 MTF는 렌즈의 설계 자료로부터 구한 MTF와 비교한 결과, 7 lp/mm 이하에서 2 % 이내의 MTF 허용오차를 만족하고 있음을 알 수 있었다.

THE CURRENT STATUS OF THE AKARI MID-INFRARED ALL-SKY DIFFUSE MAPS

  • Amatsutsu, Tomoya;Ishihara, Daisuke;Kondo, Toru;Kaneda, Hidehiro;Oyabu, Shinki;Yamagishi, Mitsuyoshi;Nakamichi, Keichiro;Sano, Hidetoshi;Onaka, Takashi
    • 천문학논총
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    • 제32권1호
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    • pp.25-27
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    • 2017
  • We are creating all-sky diffuse maps from the AKARI mid-infrared survey data with the two photometric bands centered at wavelengths of 9 and $18{\mu}m$. The AKARI mid-infrared diffuse maps achieve higher spatial resolution and higher sensitivity than the IRAS maps. In particular, the $9{\mu}m$ data are unique resources as an all-sky tracer of the emission of polycyclic aromatic hydrocarbons (PAHs). However, the original data suffer many artifacts. Thus, we have been developing correction methods. Among them, we have recently improved correction methods for the non-linearity and the reset anomaly of the detector response. These corrections successfully reduce the artifact level down to $0.1MJy\;sr^{-1}$ on average, which is essential for discussion on faint extended emission (e.g., the Galactic PAH emission). We have also made progress in the subtraction of the scattered light caused in the camera optics. We plan to release the improved diffuse maps to the public within a year.

THE NEXT-GENERATION INFRARED ASTRONOMY MISSION SPICA UNDER THE NEW FRAMEWORK

  • NAKAGAWA, TAKAO;SHIBAI, HIROSHI;ONAKA, TAKASHI;MATSUHARA, HIDEO;KANEDA, HIDEHIRO;KAWAKATSU, YASUHIRO
    • 천문학논총
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    • 제30권2호
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    • pp.621-624
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    • 2015
  • We present the current status (as of August 2014) of SPICA (Space Infrared Telescope for Cosmology and Astrophysics), which is a mission optimized for mid- and far-infrared astronomy with a cryogenically cooled 3m-class telescope. SPICA is expected to achieve high spatial resolution and unprecedented sensitivity in the mid- and far-infrared, which will enable us to address a number of key problems in present-day astronomy, ranging from the star-formation history of the universe to the formation of planets. We have carried out the "Risk Mitigation Phase" activity, in which key technologies essential to the realization of the mission have been extensively developed. Consequently, technical risks for the success of the mission have been significantly mitigated. Along with these technical activities, the international collaboration framework of SPICA has been revisited, which resulted in la arger contribution from ESA than that in the original plan. To enable the ESA participation under the new framework, a SPICA proposal to ESA is under consideration as a medium-class mission under the framework of the ESA Cosmic Vision. The target launch year of SPICA under the new framework is the mid-2020s.

중적외선 영역의 DLC 코팅된 ZnS 기판의 광학 특성 (Optical Properties of DLC-coated ZnS Substrates in the Mid-infrared Region)

  • 권태형;여서영;김창일;남산;권민철;추병욱;백종후
    • 센서학회지
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    • 제28권2호
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    • pp.101-105
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    • 2019
  • ZnS substrates with excellent transmittance in the mid-infrared region ($3-5{\mu}m$) were prepared using hot pressing instead of conventional chemical vapor deposition (CVD). Diamond-like carbon(DLC) was coated on either one or both sides of the ZnS substrates to improve their mechanical properties and transmittance. More specifically DLC was coated using CVD with an Ar and $C_2H_2$ mixed gas, and Ge was used as the bonding layer. During CVD, the bias voltage was fixed to 500 V and analyzed by Fourier transform infrared spectroscopy (FT-IR), nanoindenter, scanning electron microscope and energy dispersive spectrometry. Results of hardness analysis using the nanoindenter, showed that DLC coating increased from 5.9 to 17.7 GPa after deposition. The FT-IR spectroscopy results showed that, in the mid-infrared region ($3-5{\mu}m$), the average transmittance of the samples with DLC coating on one and both sides increased by approximately 6% and approximately 11.2% respectively. In conclusion, the DLC coating improved the durability and transmittance of the ZnS substrates.

Chalcogenide 광섬유를 이용한 호흡측정 센서 개발을 위한 기초 연구 (Feasibility study on the development of respiration sensor using a chalcogenide optical fiber)

  • 유욱재;조동현;장경원;오정은;이봉수;탁계래
    • 센서학회지
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    • 제16권5호
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    • pp.331-336
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    • 2007
  • In this study, we have fabricated an infrared optical fiber based sensor which can monitor the respiration of a patient. The design of a chalcogenide optical fiber based sensor is suitable for insertion into a high electro-magnetic field environment because the sensor consists of low cost and compact mid-infrared components such as an infrared light source, a chalcogenide optical fiber and a thermopile sensor. A fiber-optic respiration sensor is capable of detecting carbon dioxide ($CO_{2}$) in exhalation of a patient using the infrared absorption characteristics of carbon gases. The modulated infrared radiation due to the presence of carbon dioxide is guided to the thermopile sensor via a chalcogenide receiving fiber. It is expected that a mid-infrared fiber-optic respiration sensor which can be developed based on the results of this study would be highly suitable for respiration measurements of a patient during the procedure of an MRI.

MID- AND FAR-INFRARED PROPERTIES OF LOCAL ACTIVE GALACTIC NUCLEI

  • Ichikawa, Kohei;Ueda, Yoshihiro;Terashima, Yuichi;Oyabu, Shinki;Gandhi, Poshak;Matsuta, Keiko;Nakagawa, Takao
    • 천문학논총
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    • 제27권4호
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    • pp.275-279
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    • 2012
  • We investigate the mid-infrared (MIR) to far-infrared (FIR) properties of a nearly complete sample of local active galactic nuclei (AGNs) detected in the Swift/Burst Alert telescope (BAT) all-sky hard X-ray (14-195 keV) survey, based on the cross correlation with the infrared survey catalogs of AKARI, IRAS and WISE. Out of 135 non-blazar AGNs in the Swift/BAT 9-month catalog, we obtain the MIR photometric data for 128 sources in either the 9, 12, 18, 22, and $25{\mu}m$ band. We find a good correlation between their hard X-ray and MIR luminosities ranging three orders of magnitude (42 < log ${\lambda}L_{\lambda}$(9, $18{\mu}m$) < 45), which is tighter than that with the FIR luminosities at $90{\mu}m$. Both X-ray unabsorbed and absorbed AGNs follow the same correlation, implying isotropic infrared emission, as expected in clumpy dust tori models rather than homogeneous ones.

레이저 자기공명 분광기용 광대역 CO 레이저의 개발 (Development of a Broad-Band CO laser for the Laser Magnetic Resonance Spectrometer)

  • 김용평
    • 한국광학회:학술대회논문집
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    • 한국광학회 1989년도 제4회 파동 및 레이저 학술발표회 4th Conference on Waves and lasers 논문집 - 한국광학회
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    • pp.70-72
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    • 1989
  • The laser magnetic resonance (LMR) which makes use of paramagnetic properties of transient species is a powerful technique for the study of molecular radical ions. A liquid nitrogen cooled cw CO laser is developed for the LMR spectrometer in the mid-infrared region of the spectrum. The laser mid-infrared region of the spectrum. The laser system is designed to allow broad-band operation from 5 to 8${\mu}{\textrm}{m}$. The design details will be presented.

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