RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • SCISCIESCOPUS

        Excitation of Molecular Hydrogen in the Orion Bar PhotodissociationRegion from a Deep Near-infrared IGRINS Spectrum

        Kaplan, Kyle F.,Dinerstein, Harriet L.,Oh, Heeyoung,Mace, Gregory N.,Kim, Hwihyun,Sokal, Kimberly R.,Pavel, Michael D.,Lee, Sungho,Pak, Soojong,Park, Chan,Oh, Jae Sok,Jaffe, Daniel T. American Astronomical Society 2017 The Astrophysical journal Vol.838 No.2

        <P>We present a deep near-infrared spectrum of the Orion Bar Photodissociation Region (PDR) taken with the Immersion Grating INfrared Spectrometer (IGRINS) on the 2.7 m telescope at the McDonald Observatory. IGRINS has high spectral resolution (R similar to 45,000) and instantaneous broad wavelength coverage (1.45-2.45 mu m), enabling us to detect 87 emission lines from rovibrationally excited molecular hydrogen (H-2) that arise from transitions out of 69 upper rovibration levels of the electronic ground state. These levels cover a large range of rotational and vibrational quantum numbers and excitation energies, making them excellent probes of the excitation mechanisms of H2 and physical conditions within the PDR. The Orion Bar PDR is thought to consist of cooler high density clumps or filaments (T = 50-250 K, n(H) = 10(5)-10(7) cm(-3)) embedded in a warmer lower density medium (T = 250-1000 K, n(H) = 10(4)-10(5) cm(-3)). We fit a grid of constant temperature and density Cloudy models, which recreate the observed H2 level populations well, to constrain the temperature to a range of 600-650. K and the density to n(H) = 2.5 x 10(3) -10(4) cm(-3). The best-fit model gives T = 625 K and n(H) = 5 x 10(3) cm(-3). This well-constrained warm temperature is consistent with kinetic temperatures found by other studies for the Orion Bar's lower density medium. However, the range of densities well fit by the model grid is marginally lower than those reported by other studies. We could be observing lower density gas than the surrounding medium, or perhaps a density-sensitive parameter in our models is not properly estimated.</P>

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼