Sobral, D. and Best, P. N. and Geach, J. E. and Smail, Ian and Kurk, J. and Cirasuolo, M. and Casali, M. and Ivison, R. J. and Coppin, K. and Dalton, G. B. (2009) Bright Lyα emitters at z ~ 9:constraints on the LF from HizELS. Monthly Notices of the Royal Astronomical Society: Letters, 398 (1). L68-L72. ISSN 1745-3933
Full text not available from this repository.Abstract
New results are presented, as part of the Hi-z Emission Line Survey (HizELS), from the largest area survey to date (1.4 deg 2) for Lyα emitters (LAEs) at z ~ 9. The survey, which is primarily targeting Hα emitters at z <3, uses the Wide Field CAMera on the United Kingdom Infrared Telescope and a custom narrow-band filter in the J band and reaches a Lyα luminosity limit of ~10 43.8ergs -1 over a co-moving volume of 1.12 × 10 6 Mpc 3 at z = 8.96 ± 0.06. Only two candidates were found out of 1517 line emitters and those were rejected as LAEs after follow-up observations. The limit on the space density of bright LAEs is improved by three orders of magnitude, consistent with suppression of the bright end of the Lyα luminosity function beyond z ~ 6. Combined with upper limits from smaller but deeper surveys, this rules out some of the most extreme models for high-redshift LAEs. The potential contamination of future narrow-band Lyα surveys at z > 7 by Galactic brown dwarf stars is also examined, leading to the conclusion that such contamination may well be significant for searches at 7.7 <z <8.0, 9.1 <z <9.5 and 11.7 <z <12.2.