Abstract
The term proximity effect refers to the relative lack of Lyα absorption in quasar spectra close to the ionizing source, produced by the enhanced photoionization rate due the local radiation field. This effect can be detected both by looking along the line of sight of the quasar, (proximity effect along the line of sight) and also by studying the effect produced in the Lyα forest of a bright quasar by a foreground source located close to the quasar line of sight (transverse proximity effect). The proximity effect has been appreciated as a tool to investigate on the ionization level of the Universe at redshifts approaching the reionization epoch, and to study the environment and properties of quasars. In this work we discuss the limits related to the use of the proximity effect along the lines of sight towards high-z quasars to measure the neutral hydrogen fraction at z ≈ 6. Moreover, we present the first-ever detection of the transverse proximity effect in the HI Lyα forest.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
