The proximity Effect on the Lyman alpha Forest due to a Foreground QSO

1995/04/06 by A. Fernandez-Soto, X. Barcons, Fernandez-Soto, A. +5
Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #astro-ph

paper · pdf · doi:10.48550/arxiv.astro-ph/9504017

2 pages uuencoded compressed PostScript file. To appear in the Proceedings of the 1994 ESO Workshop on QSO Absorption lines. Summary of a larger work submitted to MNRAS

arxiv created 1995/04/06 · arxiv updated 2009/12/01

Abstract

We present the results of our study on three close pairs of QSOs. Our results are consistent with the existence of a proximity effect due to the foreground QSO, but due to its weakness we can only reject the absence of such effect at approx. 1 sigma level. By modelling this proximity effect in terms of a simple photoionisation model, we find the best value for the UV ionizing background to be approx. 10**(-20.5) erg cm**(-2) s**(-1) Hz**(-1) srad**(-1) at the Lyman limit, and an absolute lower limit (95% confidence) of 10**(-21.8) in the same units. This lower limit rejects a number of models for the UV background where it is mostly contributed by QSOs and absorption by Lyman limit systems is taken into account.

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