The ISO Long-Wavelength Spectrometer

Clegg, P. E.; Ade, Peter A. R.; Armand, Céline; Baluteau, Jean-Paul; Barlow, M. J.; Buckley, M. A.; Berges, J.; Burgdorf, M.; Caux, E.; Ceccarelli, C.; Cerulli, R.; Church, S.; Cotin, F.; Cox, P.; Cruvellier, P.; Culhane, J. L.; Davis, G. R.; Giorgio, A. Di; Diplock, B. R.; Drummond, D.; Emery, Roger; Ewart, J. D.; Fischer, J.; Furniss, I.; Glencross, W. M.; Greenhouse, Matthew A.; Griffin, M. J.; Gry, C.; Harwood, A. S.; Hazell, A.; Joubert, M.-F.; King, Kenneth J.; Lim, T.; Liseau, R.; Long, Jiale; Lorenzetti, D.; Molinari, S.; Murray, Alexander; Naylor, David; Nisini, B.; Norman, K.; Omont, A.; Orfei, R.; Patrick, T. J.; Pequignot, D.; Pouliquen, Dominque; Price, M. C.; Nguyen-Q-Rieu,; Rogers, Anne; Robinson, F. David; Saïsse, M.; Saraceno, P.; Serra, G.; Sidher, S.; Aj, Smith; Smith, H. A.; Spinoglio, L.; Swinyard, B. M.; Texier, D.; Towlson, W. A.; Trams, N. R.; Unger, S. J.; White, G. J.

doi:10.21236/ada464621

Cited by 142 publications

(139 citation statements)

References 3 publications

Supporting

Mentioning

139

Contrasting

Order By: Relevance

“…ISO spectra observed using the Short Wavelength Spectrometer (SWS; de Graaw et al 1996) and Long Wavelength Spectrometer (LWS; Clegg et al 1996) have previously been analysed, showing that the majority of the detected features in the FIR range are due to the rotational transitions of water (W Hya SWS: Neufeld et al 1996; W Hya LWS: Barlow et al 1996;R Cas LWS: Truong-Bach et al 1999; VY CMa SWS: Neufeld et al 1999).…”

Section: Introductionmentioning

confidence: 99%

The ISO Long Wavelength Spectrometer line spectrum of VY Canis Majoris and other oxygen-rich evolved stars

Polehampton

Menten

Tak

et al. 2010

A&A

View full text Add to dashboard Cite

Context. The far-infrared spectra of circumstellar envelopes around various oxygen-rich stars were observed using the ISO Long Wavelength Spectrometer (LWS). These have been shown to be spectrally rich, particularly in water lines, indicating a high H 2 O abundance. Aims. We have examined high signal-to-noise ISO LWS observations of the luminous supergiant star, VY CMa, with the aim of identifying all of the spectral lines. By paying particular attention to water lines, we aim to separate the lines due to other species, in particular, to prepare for forthcoming observations that will cover the same spectral range using Herschel PACS and at higher spectral resolution using Herschel HIFI and SOFIA. Methods. We have developed a fitting method to account for blended water lines using a simple weighting scheme to distribute the flux. We have used this fit to separate lines due to other species which cannot be assigned to water. We have applied this approach to several other stars which we compare with VY CMa. Results. We present line fluxes for the unblended H 2 O and CO lines, and present detections of several possible ν 2 = 1 vibrationally excited water lines. We also identify blended lines of OH, one unblended and several blended lines of NH 3 , and one possible detection of H 3 O + . Conclusions. The spectrum of VY CMa shows a detection of emission from virtually every water line up to 2000 K above the ground state, as well as many additional higher energy and some vibrationally excited lines. A simple rotation diagram analysis shows large scatter (probably due to some optically thick lines). The fit gives a rotational temperature of 670 +210 −130 K, and lower limit on the water column density of (7.0 ± 1.2) × 10 19 cm −2 . We estimate a CO column density ∼100 times lower, showing that water is the dominant oxygen carrier. The other stars that we examined have similar rotation temperatures, but their H 2 O column densities are an order of magnitude lower (as are the mass loss rates).

show abstract

Section: Introductionmentioning

confidence: 99%

The ISO Long Wavelength Spectrometer line spectrum of VY Canis Majoris and other oxygen-rich evolved stars

Polehampton

Menten

Tak

et al. 2010

A&A

View full text Add to dashboard Cite

show abstract

“…Photometrically useful observations of asteroids from ISOPHOT (Lemke et al 1996), SWS (de Graauw et al 1996) and LWS (Clegg et al 1996) are presented and discussed. We summarize these new observations and the special data reduction procedures which were necessary to calibrate the observations exclusively against stars and planets (Sect.…”

Section: Introductionmentioning

confidence: 99%

Asteroids as calibration standards in the thermal infrared for space observatories

Müller

Lagerros

2002

A&A

View full text Add to dashboard Cite

Abstract.Asteroids have been used extensively as calibration sources for the Infrared Space Observatory (ISO) and are planned to be used by future groundbased, airborne and space-based projects in the thermal infrared (IR) and in the sub-millimetre. We summarize the general IR observational parameters with a focus on space observatories and discuss brightness variations, apparent velocities and background influences. During the ISO mission ten wellstudied asteroids were used for the photometric calibration of ISOPHOT, but additionally the bright asteroids turned out to be of great interest for many technical tests and calibration aspects. We evaluated the different applications, like testing the photometry of the spectrometers, validation of relative spectral response functions, determination of beam profiles or colour correction tests. The description of the asteroids' thermal emission has been obtained by a recent thermophysical model (TPM). The important model aspects are size, albedo, shape together with the spin vector, a beaming model, thermal inertia and a wavelength-dependent emissivity. With a large sample of observational data provided by three different ISO instruments we had for the first time the possibility to study the thermal emission of several asteroids in detail. The intercomparison between results from different instruments allowed us to distinguish between observational errors and model shortcomings. It turned out that the accuracy of TPM predictions is in many cases strongly related to the limited knowledge of the asteroid shapes. The concepts of beaming, thermal inertia and wavelength dependent emissivities were nicely confirmed for a wide range of observing and illumination geometries under many aspect angles for different asteroids. The TPM predictions for Ceres, Pallas and Vesta are accurate within 5% over the full wavelength range from 5 to 200 µm, for Hygiea and a few other asteroids the predictions and observations agree within 10 to 15%. We found similar emissivity behaviour for the four large asteroids over the full ISO wavelength range. Up to now, no clear spectral features have been seen in the asteroid far-IR spectra.

show abstract

“…We present accurate frequencies and line strengths for the 2 Π 3/2 J = 5/2-3/2 transition calculated from laboratory measurements. We then present observations of this transition towards Sgr B2 using the ISO Long Wavelength Spectrometer (LWS; Clegg et al 1996) …”

Section: Introductionmentioning

confidence: 99%

Far-infrared detection of $^{\mathsf{17}}$OH towards Sagittarius B2

Polehampton

Brown

Swinyard

et al. 2003

A&A

Self Cite

View full text Add to dashboard Cite

Abstract. The frequencies and line strengths of the 2 Π 3/2 J = 5/2-3/2 rotational transition of 17 OH have been calculated from an analysis of its far-infrared laser magnetic resonance spectrum. These results have been used to make the first detection of a pure rotational transition of 17 OH in the ISM. Two resolved components of this transition appear in absorption towards the giant molecular cloud Sagittarius B2, which was observed at a spectral resolution of 33 km s −1 with the Fabry-Pérot mode of the ISO Long Wavelength Spectrometer. The corresponding transition of 18 OH was also observed and its line shape was modelled using H  measurements. The 18 O/ 17 O ratio of 3.5 was then used to compare this with the observed 17 OH line shape.

show abstract

The ISO Long-Wavelength Spectrometer

Cited by 142 publications

References 3 publications

The ISO Long Wavelength Spectrometer line spectrum of VY Canis Majoris and other oxygen-rich evolved stars

The ISO Long Wavelength Spectrometer line spectrum of VY Canis Majoris and other oxygen-rich evolved stars

Asteroids as calibration standards in the thermal infrared for space observatories

Far-infrared detection of $^{\mathsf{17}}$OH towards Sagittarius B2

Contact Info

Product

Resources

About