%0 Generic %1 Clément2011 %A Clément, B. %A Cuby, J. G. %A Courbin, F. %A Fontana, A. %A Freudling, W. %A Fynbo, J. %A Gallego, J. %A Hibon, P. %A Kneib, J. P. %A Fèvre, O. Le %A Lidman, C. %A McMahon, R. %A Milvang-Jensen, B. %A Moller, P. %A Moorwood, A. %A Nilsson, K. K. %A Pentericci, L. %A Venemans, B. %A Villar, V. %A Willis, J. %D 2011 %K igm lumfunc lya reionization %T Evolution of the Ly-alpha luminosity function from z = 6.5 to z = 7.7: evidence for the epoch of reionization ? %U http://arxiv.org/abs/1105.4235 %X Aims. Ly-alpha emitters (LAEs) can be detected out to very high redshifts, during the epoch of reionization. The evolution of the LAE luminosity function with redshift is a direct probe of the Ly-alpha transmission of the intergalactic medium (IGM), and therefore of the IGM neutral-hydrogen fraction. Measuring the Ly-alpha luminosity function (LF) of Ly-alpha emitters at redshift z = 7.7 therefore allows us to constrain the ionizing state of the Universe at this redshift. Methods. We observe three 7.5'x7.5' fields with the HAWK-I instrument at the VLT with a narrowband filter centered at 1.06 $\mu$m, targeting Ly-alpha emitters at redshift z ~ 7.7. The fields are chosen for the availability of multi-wavelength data. One field is a galaxy cluster, the Bullet Cluster, allowing us to use gravitational amplification to probe luminosities fainter than in the field. The two other fields are sub-areas of the GOODS Chandra Deep Field South and CFHTLS-D4 deep field. We select z = 7.7 LAE candidates from a variety of color criteria, in particular from the absence of detection in the optical bands. Results. We do not find LAE candidates at z = 7.7 in ~2.4 x 10^4 Mpc^3 down to a narrow band AB magnitude of ~ 26, which allows us to infer robust constraints on the Ly-alpha LAE luminosity function at this redshift. Conclusions. The luminosity functions of lower redshift LAEs do not all agree. Depending on which values we refer to at redshift 6.5, we exclude a non evolution scenario at 85% confidence without requiring a strong change in the IGM Ly-alpha transmission, or at 99% confidence with a significant quenching of the IGM Ly-alpha transmission, possibly due to a strong increase of the high neutral-hydrogen fraction between z = 6.5 and z = 7.7.

@misc{Clément2011, abstract = { Aims. Ly-alpha emitters (LAEs) can be detected out to very high redshifts, during the epoch of reionization. The evolution of the LAE luminosity function with redshift is a direct probe of the Ly-alpha transmission of the intergalactic medium (IGM), and therefore of the IGM neutral-hydrogen fraction. Measuring the Ly-alpha luminosity function (LF) of Ly-alpha emitters at redshift z = 7.7 therefore allows us to constrain the ionizing state of the Universe at this redshift. Methods. We observe three 7.5'x7.5' fields with the HAWK-I instrument at the VLT with a narrowband filter centered at 1.06 $\mu$m, targeting Ly-alpha emitters at redshift z ~ 7.7. The fields are chosen for the availability of multi-wavelength data. One field is a galaxy cluster, the Bullet Cluster, allowing us to use gravitational amplification to probe luminosities fainter than in the field. The two other fields are sub-areas of the GOODS Chandra Deep Field South and CFHTLS-D4 deep field. We select z = 7.7 LAE candidates from a variety of color criteria, in particular from the absence of detection in the optical bands. Results. We do not find LAE candidates at z = 7.7 in ~2.4 x 10^4 Mpc^3 down to a narrow band AB magnitude of ~ 26, which allows us to infer robust constraints on the Ly-alpha LAE luminosity function at this redshift. Conclusions. The luminosity functions of lower redshift LAEs do not all agree. Depending on which values we refer to at redshift 6.5, we exclude a non evolution scenario at 85% confidence without requiring a strong change in the IGM Ly-alpha transmission, or at 99% confidence with a significant quenching of the IGM Ly-alpha transmission, possibly due to a strong increase of the high neutral-hydrogen fraction between z = 6.5 and z = 7.7. }, added-at = {2011-05-24T17:02:08.000+0200}, author = {Clément, B. and Cuby, J. G. and Courbin, F. and Fontana, A. and Freudling, W. and Fynbo, J. and Gallego, J. and Hibon, P. and Kneib, J. P. and Fèvre, O. Le and Lidman, C. and McMahon, R. and Milvang-Jensen, B. and Moller, P. and Moorwood, A. and Nilsson, K. K. and Pentericci, L. and Venemans, B. and Villar, V. and Willis, J.}, biburl = {https://www.bibsonomy.org/bibtex/2e6a7867db50167388b857c97fcc61dc0/miki}, description = {[1105.4235] Evolution of the Ly-alpha luminosity function from z = 6.5 to z = 7.7: evidence for the epoch of reionization ?}, interhash = {359d5f024ac4eb44dcd548e69c8443a2}, intrahash = {e6a7867db50167388b857c97fcc61dc0}, keywords = {igm lumfunc lya reionization}, note = {cite arxiv:1105.4235 Comment: 14 pages, 6 figures, submitted to A&A}, timestamp = {2011-05-24T17:02:08.000+0200}, title = {Evolution of the Ly-alpha luminosity function from z = 6.5 to z = 7.7: evidence for the epoch of reionization ?}, url = {http://arxiv.org/abs/1105.4235}, year = 2011 }