Publikationsansicht

Discovery of a Giant Lyα Emitter Near the Reionization Epoch. (2009)

Abstract
Original article can be found at: http://www.iop.org/EJ/journal/ap Copyright American Astronomical Society. DOI: 10.1088/0004-637X/696/2/1164 [Full text of this article is not available in the UHRA]. We report the discovery of a giant Lyα emitter (LAE) with a Spitzer/Infrared Array Camera (IRAC) counterpart near the reionization epoch at z = 6.595. The giant LAE is found from the extensive 1 deg2 Subaru narrowband survey for z = 6.6 LAEs in the Subaru/XMM-Newton Deep Survey (SXDS) field, and subsequently identified by deep spectroscopy of Keck/DEIMOS and Magellan/IMACS. Among our 207 LAE candidates, this LAE is not only the brightest narrowband object with L(Lyα) = 3.9 ± 0.2 × 1043 erg s–1 in our survey volume of 106 Mpc3, but also a spatially extended Lyα nebula with the largest isophotal area whose major axis is at least 3''. This object is more likely to be a large Lyα nebula with a size of 17 kpc than to be a strongly lensed galaxy by a foreground object. Our Keck spectrum with medium-high spectral and spatial resolutions suggests that the velocity width is v FWHM = 251 ± 21 km s–1, and that the line-center velocity changes by 60 km s–1 in a 10 kpc range. The stellar mass and star formation rate are estimated to be 0.9-5.0 × 1010 M and >34 M yr–1, respectively, from the combination of deep optical to infrared images of Subaru, UKIDSS-Ultra Deep Survey, and Spitzer/IRAC. Although the nature of this object is not yet clearly understood, this could be an important object for studying cooling clouds accreting onto a massive halo, or forming-massive galaxies with significant outflows contributing to cosmic reionization and metal enrichment of intergalactic medium.

Details der Publikation
Download http://hdl.handle.net/2299/3430
Herausgeber IOP Publishing
Archiv University of Hertfordshire Research Archive (United Kingdom)
Typ Article
Sprache Englisch