Sample variance and Lyman-alpha forest transmission statistics

Дата и время публикации : 2012-09-23T17:02:16Z

Авторы публикации и институты :
Emmanuel Rollinde
Tom Theuns
Joop Schaye
Isabelle Pâris
Patrick Petitjean

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: 12 pages, 9 figures, accepted for publication in MNRAS
Первичная категория: astro-ph.CO

Все категории : astro-ph.CO

Краткий обзор статьи: We compare the observed probability distribution function of the transmission in the HI Lyman-alpha forest, measured from the UVES ‘Large Programme’ sample at redshifts z=[2,2.5,3], to results from the GIMIC cosmological simulations. Our measured values for the mean transmission and its PDF are in good agreement with published results. Errors on statistics measured from high-resolution data are typically estimated using bootstrap or jack-knife resampling techniques after splitting the spectra into chunks. We demonstrate that these methods tend to underestimate the sample variance unless the chunk size is much larger than is commonly the case. We therefore estimate the sample variance from the simulations. We conclude that observed and simulated transmission statistics are in good agreement, in particular, we do not require the temperature-density relation to be ‘inverted’.

Category: Physics