CII Diffuse Emission Observed by IRTS

Publications of the Astronomical Society of Japan

Nakagawa, Takao³  Matsuhara, Hideo¹  Makiuti, Sin'itirou³  Hiromoto, Norihisa²  Okuda, Haruyuki³  Okumura, Ken'ichi²  Shibai, Hiroshi³ 

[1] Department of Physics, School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-01;Communications Research Laboratory, 4-2-1 Nukui-kitamachi, Koganei, Tokyo 184;The Institute of Space and Astronautical Science, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229 E-mail (HS):

关键词: "Galaxies: Milky Way";    "Interstellar: clouds";    "Interstellar: medium";    "Infrared: spectra";    Spacecraft;   

DOI  :  10.1093/pasj/48.6.L127

学科分类：天文学(综合)

来源: Oxford University Press

【 摘 要 】

TheCII158μmlineemissionandthefar-infraredcontinuumemissionat155μmwereobservedbytheFar-InfraredLineMapper(FILM)aboardtheInfraredTelescopeinSpace(IRTS)withitshighsensitivityandresolution.Theobservationwasmadealongagreatcirclecrossingthegalacticplaneatl=50°and230°.Twocomponentswerefoundintheirintensitydistributions.Thefirstcomponentconcentratesonthegalacticplane.Itisprominentontheplaneatl=50°,butisveryfaintat230°.Thesecondcomponentextendsoveratleast20°ingalacticlatitude,andhasnearlythesameintensityatbothcrossingpartsofthegalacticplane.Therefore,thefirstonecanbeascribedtoemissionfromthegalacticdisk,andthesecondcomponenttoemissionfromthelocalinterstellargas.Theintensitydistributionofthe[CII]lineofthesecondcomponentissimilartothatoftheHI21cmintegratedintensity.Thisfactsuggeststhatthelocal[CII]emissioncomponentarisesintheHI21cmlineemittinggas.FromtheratiooftheCIIlineluminositytothehydrogencolumndensity,theinterstellarcoolingrateoftheHIgasis(5.6±2.6)×10−27ergs−1/H-atom,correspondingtothecoldneutralgaswhosepressureisafewhundredcm−3K.

【 授权许可】

Unknown