We present a spectroscopic survey of Ly α emitters in the Extended Groth Strip (EGS) field, targeting the regime near the Epoch of Reionization. Using Keck/DEep Imaging Multi-Object Spectrograph, we observed 947 high-z candidates with photometric redshifts from 3 < zphot < 7 and down to an H-band (Hubble Space Telescope/Wide Field Camera 3 F160W) magnitude limit of <27.5. Observations were taken over the course of eight nights, with integration times ranging from 4 to 7.8 h. Our survey secured 137 unique redshifts, 126 of which are Ly α emitters at 2.8 < z < 6.3 with a mean redshift of $\overline{z} = 4.3$. We provide a comprehensive redshift catalogue for our targets, as well as the reduced one- and two-dimensional spectra for each object. These observations will provide an important auxiliary data set for the JWST Directors Discretionary Early Release Science programme the Cosmic Evolution Early Release Science Survey, which recently completed near- and mid-infrared imaging and spectroscopy of galaxies in the EGS field.
A UV-visible prime focus camera for the Keck telescopes
Many areas of astronomical research rely on deep blue wide-field imaging. Mauna Kea enjoys the very best UV transparency from the ground and the Keck telescopes with 10 meter f/1.75 primaries are well suited to a prime focus camera with a large angular field. Swinburne University leads a proposal to provide a camera (KWFI, for Keck Wide Field Imager) that is optimized in the UV but works well to 1μm wavelength. Keck has interchangeable top end modules, of which one is now unused and easily capable of housing the required corrector lens and detector enclosure. This paper concentrates on details of the KWFI optical design.
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- Award ID(s):
- 2009278
- NSF-PAR ID:
- 10285650
- Editor(s):
- Ellis, Simon C.; d'Orgeville, Céline
- Date Published:
- Journal Name:
- Proceedings of the SPIE
- Volume:
- 11203
- Page Range / eLocation ID:
- 14
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1117/12.2540717
