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DOE OSTI · 21474464

MAPPING THE DIFFUSE ULTRAVIOLET SKY WITH THE GALAXY EVOLUTION EXPLORER

Murthy, Jayant·Sujatha, N V
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Abstract

We present a map of the diffuse ultraviolet cosmic background in two wavelength bands (FUV: 1530 A and NUV: 2310 A) over almost 75% of the sky using archival data from the Galaxy Evolution Explorer (GALEX) mission. Most of the diffuse flux is due to dust-scattered starlight and follows a cosecant law with slopes of 545 photons cm{sup -2} s{sup -1} sr{sup -1} A{sup -1} and 433 photons cm{sup -2} s{sup -1} sr{sup -1} A{sup -1} in the FUV and NUV bands, respectively. There is a strong correlation with the 100 {mu}m Infrared Astronomy Satellite (IRAS) flux with an average UV/IR ratio of 300 photons cm{sup -2} s{sup -1} sr{sup -1} A{sup -1} (MJy sr{sup -1}){sup -1} in the FUV band and that of 220 photons cm{sup -2} s{sup -1} sr{sup -1} A{sup -1} (MJy sr{sup -1}){sup -1} in the NUV band but with significant variations over the sky. In addition to the large-scale distribution of the diffuse light, we note a number of individual features including bright spots around the hot stars Spica and Achernar.

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79 ASTRONOMY AND ASTROPHYSICSASTRONOMYBOSONSDUSTSELECTROMAGNETIC RADIATIONELEMENTARY PARTICLESEVOLUTIONGALACTIC EVOLUTIONGALAXIESMASSLESS PARTICLESPHOTONSRADIATIONSSTARSULTRAVIOLET RADIATION

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Murthy, Jayant, Sujatha, N V. 2010-12-01. MAPPING THE DIFFUSE ULTRAVIOLET SKY WITH THE GALAXY EVOLUTION EXPLORER. https://doi.org/10.1088/0004-637x%2F724%2F2%2F1389

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