S
S. J. Unger
Researcher at University of London
Publications - 18
Citations - 390
S. J. Unger is an academic researcher from University of London. The author has contributed to research in topics: Spectroscopy & Spectrometer. The author has an hindex of 8, co-authored 18 publications receiving 386 citations. Previous affiliations of S. J. Unger include Queen Mary University of London & Rutherford Appleton Laboratory.
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Journal ArticleDOI
ISO LWS Spectroscopy of M82: A Unified Evolutionary Model
James Colbert,Matthew A. Malkan,Peter E. Clegg,Pierre Cox,Jacqueline Fischer,Steven D. Lord,M. L. Luhman,Shobita Satyapal,Howard A. Smith,Luigi Spinoglio,Gordon J. Stacey,S. J. Unger +11 more
TL;DR: In this article, the authors presented the first complete far-infrared spectrum (43-197 μm) of M82, the brightest infrared galaxy in the sky, taken with the Long Wavelength Spectrometer of the Infrared Space Observatory (ISO), and fitted their ratios to a combination starburst and photodissociation region (PDR) model.
ISO LWS Spectroscopy of M82: A Unified Evolutionary Model
James Colbert,Matthew A. Malkan,P. E. Blegg,Pierre Cox,J. Fischer,S. D. Lord,M. L. Luhman,Shobita Satyapal,H. A. Smith,Luigi Spinoglio,Gordon J. Stacey,S. J. Unger +11 more
Abstract: We present the first complete far-infrared spectrum (43-197 μm) of M82, the brightest infrared galaxy in the sky, taken with the Long Wavelength Spectrometer of the Infrared Space Observatory (ISO). We detected seven fine structure emission lines, [O I] 63 and 145 μm, [O III] 52 and 88 μm , [N II] 122 μm, [N III] 57 μm, and [C II] 158 μm, and fitted their ratios to a combination starburst and photodissociation region (PDR) model. The best fit is obtained with H II regions with n = 250 cm-3, an ionization parameter of 10-3.5, and PDRs with n = 103.3 cm-3 and a far-ultraviolet flux of G0 = 102.8. We applied both continuous and instantaneous starburst models, with our best fit being a 3-5 Myr old instantaneous burst model with a 100 M⊙ cutoff. We also detected the ground-state rotational line of OH in absorption at 119.4 μm. No excited level OH transitions are apparent, indicating that the OH is almost entirely in its ground state with a column density ∼4 × 1014 cm-2. The spectral energy distribution over the long-wavelength spectrometer wavelength range is well fitted with a 48 K dust temperature and an optical depth, τDust ∝ λ-1.
Journal ArticleDOI
ISO Far-IR spectroscopy of IR-bright galaxies and ULIRGs
Jacqueline Fischer,M. L. Luhman,Shobita Satyapal,Matthew A. Greenhouse,Gordon J. Stacey,Charles M. Bradford,Steven D. Lord,J. Brauher,S. J. Unger,Peter E. Clegg,Howard A. Smith,Gary J. Melnick,James Colbert,Matthew A. Malkan,Luigi Spinoglio,Pierre Cox,V. Harvey,J. P. Suter,V. Strelnitski +18 more
TL;DR: In this article, a far-infrared spectroscopy of a small sample of nearbyinfrared-bright and ultraluminous infrared galaxies (ULIRGs) with theISO Long Wavelength Spectrometer was used to find an adramatic progression in ionic/atomic fine-structure emission line and molecular/atomic absorption line characteristics.
ReportDOI
The ISO Long-Wavelength Spectrometer
P. E. Clegg,Peter A. R. Ade,C. Armand,Jean-Paul Baluteau,M. J. Barlow,M. A. Buckley,J.-C. Berges,Martin Burgdorf,Emmanuel Caux,Cecilia Ceccarelli,R. Cerulli,Sarah E. Church,F. Cotin,Pierre Cox,P. Cruvellier,J. L. Culhane,Gary R. Davis,A. M. di Giorgio,B. R. Diplock,D. L.. Drummond,R. J. Emery,J. D. Ewart,J. Fischer,I. Furniss,W. M. Glencross,Matthew A. Greenhouse,Matthew Joseph Griffin,Cecile Gry,A. S. Harwood,A. Hazell,M. Joubert,K. J. King,T. L. Lim,René Liseau,J. A. Long,Dario Lorenzetti,Sergio Molinari,A. G. Murray,David A. Naylor,Brunella Nisini,K. Norman,A. Omont,R. Orfei,T. J. Patrick,D. Pequignot,D. Pouliquen,Mark C. Price,Nguyen-Q-Rieu,A. J. Rogers,F. D. Robinson,Michel Saisse,Paolo Saraceno,G. Serra,Sunil Sidher,A. F. Smith,Howard A. Smith,Luigi Spinoglio,B. M. Swinyard,D. Texier,W. A. Towlson,Norman R. Trams,S. J. Unger,Glenn J. White +62 more
TL;DR: The Long-Wavelength Spectrometer (LWS) is one of two complementary spectrometers aboard the European Space Agency's Infrared Space Observatory (ISO) (Kessler et al., 1996) as mentioned in this paper.
Posted Content
ISO Far-IR Spectroscopy of IR-Bright Galaxies and ULIRGs
Jacqueline Fischer,M. L. Luhman,Shobita Satyapal,Matthew A. Greenhouse,Gordon J. Stacey,Charles M. Bradford,Steven D. Lord,J. Brauher,S. J. Unger,Peter E. Clegg,Howard A. Smith,Gary J. Melnick,James Colbert,Matthew A. Malkan,Luigi Spinoglio,Pierre Cox,V. Harvey,J. P. Suter,V. Strelnitski +18 more
TL;DR: In this paper, far-infrared spectroscopy of a small sample of nearby infrared-bright and ultraluminous infrared galaxies (ULIRGs) with the ISO Long Wavelength Spectrometer was used to find a dramatic progression in ionic/atomic fine-structure emission line and molecular/atomic absorption line characteristics.