Published in The Astrophysical Journal Supplement Series, Volume 178, Issue 2, pp. 280-301, 2008.
astro-ph/0805.2930

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A COMPENDIUM OF FAR-INFRARED LINE AND CONTINUUM EMISSION FOR 227 GALAXIES OBSERVED BY THE INFRARED SPACE OBSERVATORY

James R. Brauher 1, Daniel A. Dale 2, George Helou 1


1 California Institute of Technology, MC 314-6, Pasadena, CA 91101
2 Department of Physics and Astronomy, University of Wyoming, Laramie, WY 82071; ddale@uwyo.edu


Abstract. Far-infrared line and continuum fluxes are presented for a sample of 227 galaxies observed with the Long Wavelength Spectrometer on the Infrared Space Observatory. The galaxy sample includes normal star-forming systems, starbursts, and active galactic nuclei covering a wide range of colors and morphologies. The dataset spans some 1300 line fluxes, 600 line upper limits, and 800 continuum fluxes. Several fine structure emission lines are detected that arise in either photodissociation or H2 regions: [O III] 52 µm, [N III] 57 µm, [O I] 63 µm, [O III] 88 µm, [N II] 122 µm, [O I] 145 µm, and [C II] 158 µm. Molecular lines such as OH at 53 µm, 79 µm, 84 µm, 119 µm, and 163 µm, and H2O at 58 µm, 66 µm, 75 µm, 101 µm, and 108 µm are also detected in some galaxies. In addition to those lines emitted by the target galaxies, serendipitous detections of Milky Way [C II] 158 µm and an unidentified line near 74 µm in NGC 1068 are also reported. Finally, continuum fluxes at 52 µm, 57 µm, 63 µm, 88 µm, 122 µm, 145 µm, 158 µm, and 170 µm are derived for a subset of galaxies in which the far-infrared emission is contained within the ~ 75" ISO LWS beam. The statistics of this large database of continuum and line fluxes, including trends in line ratios with the far-infrared color and infrared-to-optical ratio, are explored.


Keywords: infrared: galaxies - infrared: interstellar medium


Table of Contents

INTRODUCTION

THE SAMPLE AND DATA

OBSERVATIONS AND DATA ANALYSIS

THE CONTINUUM DATA
Comparison with IRAS 60 and 100 µm Data
Comparison with ISOPHOT 170 µm Continuum Data
Comparison with Models of Galaxy Infrared Spectral Energy Distributions

THE LINE DATA
Far-Infrared Fine Structure Lines
Molecular Lines
Unidentified Line
Serendipitous Galactic [C II] 158 µm

STATISTICAL TRENDS IN THE LINE DATA
[C II] 158 µm / FIR
[O I] 63 µm / FIR
[N II] 122 µm / FIR
[O III] 88 µm / FIR
[O I] 63 µm/[C II] 158 µm
[N II] 122 µm/[C II] 158 µm
[O I] 145 µm/[O I] 63 µm
([O I] 63 µm + [C II] 158 µm) / FIR
[O III] 88 µm/[C II] 158 µm
[O III] 88 µm/[O I] 63 µm
[O III] 88 µm/[N II] 122 µm

SUMMARY

APPENDIX

REFERENCES

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