COMPARING ULTRAVIOLET- AND INFRARED-SELECTED STARBURST GALAXIES IN DUST OBSCURATION AND LUMINOSITY

Journal Article · Tue Jun 01 00:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/715/2/986· OSTI ID:21450933

Sargsyan, Lusine A ^[1]; Weedman, Daniel W

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1. Byurakan Astrophysical Observatory, 378433, Byurakan, Aragatzotn Province (Armenia)

We present samples of starburst galaxies that represent the extremes discovered with infrared and ultraviolet observations, including 25 Markarian galaxies, 23 ultraviolet-luminous galaxies discovered with GALEX, and the 50 starburst galaxies having the largest infrared/ultraviolet ratios. These sources have z < 0.5 and cover a luminosity range of {approx}10{sup 4}. Comparisons between infrared luminosities determined with the 7.7 {mu}m polycyclic aromatic hydrocarbon feature and ultraviolet luminosities from the stellar continuum at 153 nm are used to determine obscuration in starbursts and dependence of this obscuration on infrared or ultraviolet luminosity. A strong selection effect arises for the ultraviolet-selected samples: the brightest sources appear bright because they have the least obscuration. Obscuration correction for the ultraviolet-selected Markarian+GALEX sample has the form log[UV(intrinsic)/UV(observed)] = 0.07({+-}0.04)M(UV) + 2.09 {+-} 0.69 but for the full infrared-selected Spitzer sample is log[UV(intrinsic)/UV(observed)] = 0.17({+-}0.02)M(UV) + 4.55 {+-} 0.4. The relation of total bolometric luminosity L {sub ir} to M(UV) is also determined for infrared-selected and ultraviolet-selected samples. For ultraviolet-selected galaxies, log L {sub ir} = -(0.33 {+-} 0.04)M(UV) + 4.52 {+-} 0.69. For the full infrared-selected sample, log L {sub ir} = -(0.23 {+-} 0.02)M(UV) + 6.99 {+-} 0.41, all for L {sub ir} in L{sub sun} and M(UV) the AB magnitude at rest frame 153 nm. These results imply that obscuration corrections by factors of 2-3 determined from reddening of the ultraviolet continuum for Lyman break galaxies with z>2 are insufficient, and should be at least a factor of 10 for M(UV) {approx} -17, with decreasing correction for more luminous sources.

• OSTI ID: 21450933
• Journal Information: Astrophysical Journal, Vol. 715, Issue 2; Other Information: DOI: 10.1088/0004-637X/715/2/986; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BOLOMETERS
DUSTS
GALACTIC EVOLUTION
LUMINOSITY
MARKARIAN GALAXIES
POLYCYCLIC AROMATIC HYDROCARBONS
RED SHIFT
ULTRAVIOLET RADIATION
AROMATICS
ELECTROMAGNETIC RADIATION
EVOLUTION
GALAXIES
HYDROCARBONS
MEASURING INSTRUMENTS
OPTICAL PROPERTIES
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
RADIATIONS