Citation:
Abstract:
Understanding the nature of distant Lyα nebulae, aka "blobs," andconnecting them to their present-day descendants requires constrainingtheir number density, clustering, and large-scale environment. Tomeasure these basic quantities, we conduct a deep narrowband imagingsurvey in four different fields, Chandra Deep Field South (CDFS),Chandra Deep Field North (CDFN), and two COSMOS subfields, for a totalsurvey area of 1.2 deg2. We discover 25 blobs at z = 2.3 withLyα luminosities of L Lyα= (0.7-8) ×1043 erg s-1 and isophotal areas of Aiso = 10-60 sq arcsec. The transition from compact Lyαemitters (LAEs; A iso ~ a few sq arcsec) to extendedLyα blobs (A iso > 10 sq arcsec) is continuous,suggesting a single family perhaps governed by similar emissionmechanisms. Surprisingly, most blobs (16/25) are in one survey field,the CDFS. The six brightest, largest blobs with L Lyαgsim 1.5×1043 erg s-1 and A iso> 16 sq arcsec lie only in the CDFS. These large, bright blobs have a
