Diffuse ultraviolet radiation in the intergalactic medium

Diffuse solar ultraviolet radiation.

The solar UV exposure to the eyes of humans is due to the direct and diffuse components of solar radiation. The direct ocular UV exposures to the eyes are reduced due to the natural aversion of the majority of people from looking directly at the sun. The diffuse UV is incident from all directions and as a result, it is more difficult to minimise the ocular exposure to this component of the sola...

The Diffuse Ultraviolet Background Radiation

I review the nature of the diffuse cosmic ultraviolet background radiation. The ultraviolet background is the last frontier: all the other diffuse backgrounds have been examined, at least at some level. The ultraviolet background has only begun to be explored; it offers rich promise of new astrophysical knowledge.

Intergalactic Medium

Diffuse Component of the Solar Ultraviolet Radiation in Tree Shade

This paper has provided the first set of quantitative data of diffuse erythemal UV and UVA in tree shade at a sub-tropical Southern Hemisphere latitude. Over the summer, approximately 60% of the erythemal UV radiation in the tree shade is due to the diffuse component. Similarly, approximately 56% of the UVA radiation in the tree shade is due to the diffuse component. In the tree shade these dif...

EXTREME ULTRAVIOLET ABSORPTION LINES IN Lyα FOREST ABSORBERS AND THE OXYGEN ABUNDANCE IN THE INTERGALACTIC MEDIUM

We create stacked composite absorption spectra from Hubble Space Telescope Faint Object Spectrograph data from four quasi-stellar objects to search for absorption lines in the extreme ultraviolet wavelength region associated with Lyα forest absorbers in the redshift range 1.6 < z < 2.9. We successfully detect O V λ630 in Lyα absorbers throughout the 1013 to 1016.2 cm−2 column density range. For...