15 research outputs found
The ISO LWS high-resolution spectral survey towards Sagittarius B2
No full textInternational audienceA full spectral survey was carried out towards the giant molecular cloud complex, Sagittarius B2 (SgrB2), using the Infrared Space Observatory (ISO) Long Wavelength Spectrometer (LWS) Fabry-Pérot mode. This provided complete wavelength coverage in the range 47-196mum (6.38-1.53THz) with a spectral resolution of 30-40kms-1. This is a unique data set covering wavelengths inaccessible from the ground. It is an extremely important region of the spectrum as it contains both the peak of the thermal emission from dust, and crucial spectral lines of key atomic (OI, CII, OIII, NII and NIII) and molecular species (NH3, NH2, NH, H2O, OH, H3O+, CH, CH2, C3, HF and H2D+). In total, 95 spectral lines have been identified and 11 features with absorption depth greater than 3sigma remain unassigned. Most of the molecular lines are seen in absorption against the strong continuum, whereas the atomic and ionic lines appear in emission (except for absorption in the OI 63mum and CII 158mum lines). SgrB2 is located close to the Galactic Centre and so many of the features also show a broad absorption profile due to material located along the line of sight. A full description of the survey data set is given with an overview of each detected species and final line lists for both assigned and unassigned features
The ISO LWS high-resolution spectral survey towards Sagittarius B2
No full textInternational audienceA full spectral survey was carried out towards the giant molecular cloud complex, Sagittarius B2 (SgrB2), using the Infrared Space Observatory (ISO) Long Wavelength Spectrometer (LWS) Fabry-Pérot mode. This provided complete wavelength coverage in the range 47-196mum (6.38-1.53THz) with a spectral resolution of 30-40kms-1. This is a unique data set covering wavelengths inaccessible from the ground. It is an extremely important region of the spectrum as it contains both the peak of the thermal emission from dust, and crucial spectral lines of key atomic (OI, CII, OIII, NII and NIII) and molecular species (NH3, NH2, NH, H2O, OH, H3O+, CH, CH2, C3, HF and H2D+). In total, 95 spectral lines have been identified and 11 features with absorption depth greater than 3sigma remain unassigned. Most of the molecular lines are seen in absorption against the strong continuum, whereas the atomic and ionic lines appear in emission (except for absorption in the OI 63mum and CII 158mum lines). SgrB2 is located close to the Galactic Centre and so many of the features also show a broad absorption profile due to material located along the line of sight. A full description of the survey data set is given with an overview of each detected species and final line lists for both assigned and unassigned features
The ISO LWS high-resolution spectral survey towards Sagittarius B2
No full textInternational audienceA full spectral survey was carried out towards the giant molecular cloud complex, Sagittarius B2 (SgrB2), using the Infrared Space Observatory (ISO) Long Wavelength Spectrometer (LWS) Fabry-Pérot mode. This provided complete wavelength coverage in the range 47-196mum (6.38-1.53THz) with a spectral resolution of 30-40kms-1. This is a unique data set covering wavelengths inaccessible from the ground. It is an extremely important region of the spectrum as it contains both the peak of the thermal emission from dust, and crucial spectral lines of key atomic (OI, CII, OIII, NII and NIII) and molecular species (NH3, NH2, NH, H2O, OH, H3O+, CH, CH2, C3, HF and H2D+). In total, 95 spectral lines have been identified and 11 features with absorption depth greater than 3sigma remain unassigned. Most of the molecular lines are seen in absorption against the strong continuum, whereas the atomic and ionic lines appear in emission (except for absorption in the OI 63mum and CII 158mum lines). SgrB2 is located close to the Galactic Centre and so many of the features also show a broad absorption profile due to material located along the line of sight. A full description of the survey data set is given with an overview of each detected species and final line lists for both assigned and unassigned features
The ISO LWS high-resolution spectral survey towards Sagittarius B2
No full textInternational audienceA full spectral survey was carried out towards the giant molecular cloud complex, Sagittarius B2 (SgrB2), using the Infrared Space Observatory (ISO) Long Wavelength Spectrometer (LWS) Fabry-Pérot mode. This provided complete wavelength coverage in the range 47-196mum (6.38-1.53THz) with a spectral resolution of 30-40kms-1. This is a unique data set covering wavelengths inaccessible from the ground. It is an extremely important region of the spectrum as it contains both the peak of the thermal emission from dust, and crucial spectral lines of key atomic (OI, CII, OIII, NII and NIII) and molecular species (NH3, NH2, NH, H2O, OH, H3O+, CH, CH2, C3, HF and H2D+). In total, 95 spectral lines have been identified and 11 features with absorption depth greater than 3sigma remain unassigned. Most of the molecular lines are seen in absorption against the strong continuum, whereas the atomic and ionic lines appear in emission (except for absorption in the OI 63mum and CII 158mum lines). SgrB2 is located close to the Galactic Centre and so many of the features also show a broad absorption profile due to material located along the line of sight. A full description of the survey data set is given with an overview of each detected species and final line lists for both assigned and unassigned features
A far-infrared molecular and atomic line survey of the Orion KL region
No full textInternational audienceWe have carried out a high spectral resolution (lambda/Deltalambda ~ 6800-9700) line survey towards the Orion Kleinmann-Low (KL) cluster from 44 to 188 mum. The observations were taken with the Long Wavelength Spectrometer (LWS) in Fabry-Pérot mode, on board the Infrared Space Observatory (ISO). A total of 152 lines are clearly detected and a further 34 features are present as possible detections. The spectrum is dominated by the molecular species H2O, OH and CO, along with [OI] and [CII] lines from photodissociation region (PDR) or shocked gas and [O III] and [NIII] lines from the foreground M42 HII region. Several isotopic species, as well as NH3, are also detected. HDO and H3O+ are tentatively detected for the first time in the far-infrared (FIR) range towards Orion KL. A basic analysis of the line observations is carried out, by comparing with previous measurements and published models and deriving rotational temperatures and column densities in the case of the molecular species
A far-infrared molecular and atomic line survey of the Orion KL region
No full textInternational audienceWe have carried out a high spectral resolution (lambda/Deltalambda ~ 6800-9700) line survey towards the Orion Kleinmann-Low (KL) cluster from 44 to 188 mum. The observations were taken with the Long Wavelength Spectrometer (LWS) in Fabry-Pérot mode, on board the Infrared Space Observatory (ISO). A total of 152 lines are clearly detected and a further 34 features are present as possible detections. The spectrum is dominated by the molecular species H2O, OH and CO, along with [OI] and [CII] lines from photodissociation region (PDR) or shocked gas and [O III] and [NIII] lines from the foreground M42 HII region. Several isotopic species, as well as NH3, are also detected. HDO and H3O+ are tentatively detected for the first time in the far-infrared (FIR) range towards Orion KL. A basic analysis of the line observations is carried out, by comparing with previous measurements and published models and deriving rotational temperatures and column densities in the case of the molecular species
FIRST-SPIRE spectrometer: a novel imaging FTS for the submillimeter
No full textThe SPIRE instrument for the FIRST mission will consist of a three band imaging submillimeter photometer and a two band imaging Fourier Transform Spectrometer (FTS) optimized for the 200 - 400 micrometers range, and with extended coverage out to 670 micrometers. The FTS will be used for follow-up spectroscopic studies of objects detected in photometric surveys by SPIRE and other facilities, and to perform medium resolving power (R approximately 500 at 250 micrometers ) imaging spectroscopy on galactic and nearby extra-galactic sources
