Abstract
In the course of our ongoing search for serendipitous high-redshift Lyα emission in deep archival Keck spectra, we discovered two very high equivalent width (W ≳ 450 Å, 2 σ) Lyα emission-line candidates at z ~ 3 in a moderate dispersion (λ/Δλ ≃ 1200) spectrogram. Both lines have low velocity dispersions (σv ~ 60 km s-1) and deconvolved radii r ≈ 1 h kpc. We argue that the lines are Lyα and are powered by stellar ionization. The surface density of robust, high equivalent width Lyα candidates is estimated to be ~3 ± 2 arcmin-2 per unit redshift at z ≃ 3, consistent with the recent estimate of Cowie & Hu. The Lyα emission-line source characteristics are consistent with the galaxies undergoing their first burst of star formation, i.e., with being primeval. Source sizes and velocity dispersions are comparable to the theoretical primeval galaxy model of Lin & Murray based on the inside out, self-similar collapse of an isothermal sphere. In this model, star formation among field galaxies is a protracted process.
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.
