Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-11-21
Astrophys.J.693:1579-1587,2009
Astronomy and Astrophysics
Astrophysics
10 pages, 7 figures, accepted for publication in ApJ
Scientific paper
10.1088/0004-637X/693/2/1579
To obtain an unbiased sample of bright LyA blobs [L(LyA) > 10^43 ergs/s], we have undertaken a blind, wide-field, narrow-band imaging survey in the NOAO Deep Wide Field Survey Bootes field with the Steward Bok-2.3m telescope. After searching over 4.82 sq. degrees at z=2.3, we discover four LyA blobs with L(LyA) = 1.6-5.3 x 10^43 ergs/s, isophotal areas of 28-57 sq. arcsec, and broad LyA line profiles (FWHM = 900-1250 km/s). In contrast with the extended Lyman alpha halos associated with high-z radio galaxies, none of our four blobs are radio-loud. The X-ray luminosities and optical spectra of these blobs are diverse. Two blobs (3 and 4) are X-ray-detected with L_X(2-7 keV) = 2-4 x 10^44 ergs/s and have broad optical emission lines (C IV) characteristic of AGN, implying that 50% of our sample blobs are associated with strong AGN. The other 50% of blobs (1 and 2) are not X-ray or optically-detected as AGN down to similar limits. The number density of the four blobs is ~3 x 10^{-6} Mpc^{-3}, comparable to that of galaxy clusters at similar redshifts and 3x lower than that found in the SSA22 proto-cluster at z=3.1, even after accounting for the over-density of that region. The two X-ray undetected blobs are separated by only 70" (550 kpc) and have almost identical redshifts (< 360 kpc along the line-of-sight), suggesting that they are part of the same system. Given the rarity of the blobs and our discovery of a close pair, we speculate that blobs occupy the highest density regions and thus may be precursors of today's rich cluster galaxies.
Dav'e Romeel
Eisenstein Daniel
Tremonti Christy
Yang Yujin
Zabludoff Ann
No associations
LandOfFree
Extended Lyman Alpha Nebulae at z ~ 2.3: An Extremely Rare and Strongly Clustered Population? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Extended Lyman Alpha Nebulae at z ~ 2.3: An Extremely Rare and Strongly Clustered Population?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Extended Lyman Alpha Nebulae at z ~ 2.3: An Extremely Rare and Strongly Clustered Population? will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-162618