Exploring the high-redshift Universe
The Nature of Hbeta+[OIII] and [OII] emitters to z ~ 5 with HiZELS: stellar mass functions and the evolution of EWs
Ali Ahmad Khostovan
David Sobral (Lancaster Univ.), Bahram Mobasher (UCR), Ian Smail (ICC-Durham), Behnam Darvish (Caltech), Hooshang Nayyeri (UCI), Shoubaneh Hemmati (IPAC), John P. Stott (Oxford)
University of California, Riverside
I will present new results from a unique sample of ∼ 7000 narrow-band selected galaxies with strong Hβ+[Oiii] and [Oii] nebular emission lines from the High-z Emission Line Survey (HiZELS) between z ∼ 0.8 − 5.0. Our sample covers a wide range of stellar mass (Mstellar ∼ 107.5−12.0 M ), rest-frame equivalent widths (EWrest ∼ 10 − 105 Å), and line luminosities. We study the evolution of the Hβ+[Oiii]- and [Oii]-selected stellar mass functions for the first time. We find a strong evolution matching with the stellar mass growth in the mainstream literature. I will also present new results of the EWrest evolution.
We find an increasing trend up to z ∼ 2 and z ∼ 3 for Hβ+[Oiii] and [Oii], respectively.
Interestingly, we find evidence for a slower evolution for z > 2 in the Hβ+[Oiii] EWrest and a decreasing trend for z > 3 in the [Oii] EWrest evolution. I will conclude with an analysis on the shifts in the EWrest evolution and what this implies about the changes in the [Oiii]/[Oii] line ratios, an indicator of the ionization parameter.
16:30 - 18:00
EX - LT2 (200)