Central Powering of the Largest Lyman-alpha Nebula is Revealed by Polarized Radiation

Details Central Powering of the Largest Lyman-alpha Nebula is Revealed by Polarized Radiation Central Powering of the Largest Lyman-alpha Nebula is Revealed by Polarized Radiation

2011-08-16

arxiv.org/abs/1108.3332v1

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

Published in the August 18 issue of Nature. 1750 words, 3 figures, and full Supplementary Information. Version has not undergo

Scientific paper

10.1038/nature10320

High-redshift Lyman-alpha blobs are extended, luminous, but rare structures that appear to be associated with the highest peaks in the matter density of the Universe. Their energy output and morphology are similar to powerful radio galaxies, but the source of the luminosity is unclear. Some blobs are associated with ultraviolet or infrared bright galaxies, suggesting an extreme starburst event or accretion onto a central black hole. Another possibility is gas that is shock excited by supernovae. However some blobs are not associated with galaxies, and may instead be heated by gas falling into a dark matter halo. The polarization of the Ly-alpha emission can in principle distinguish between these options, but a previous attempt to detect this signature returned a null detection. Here we report on the detection of polarized Ly-alpha from the blob LAB1. Although the central region shows no measurable polarization, the polarized fraction (P) increases to ~20 per cent at a radius of 45 kpc, forming an almost complete polarized ring. The detection of polarized radiation is inconsistent with the in situ production of Ly-alpha photons, and we conclude that they must have been produced in the galaxies hosted within the nebula, and re-scattered by neutral hydrogen.

Affiliated with

Also associated with

No associations

Rating

Central Powering of the Largest Lyman-alpha Nebula is Revealed by Polarized Radiation does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Central Powering of the Largest Lyman-alpha Nebula is Revealed by Polarized Radiation, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Central Powering of the Largest Lyman-alpha Nebula is Revealed by Polarized Radiation will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-539465