J/MNRAS/403/L54 Lyα emitters (LAE) in A1689-7.1 (Matsuda+, 2010)
A search for galaxies in and around an HI overdense region at z=5.
Matsuda Y., Richard J., Smail I., Kashikawa N., Shimasaku K., Frye B.L.,
Yamada T., Nakamura Y., Hayashino T., Fujii T.
<Mon. Not. R. Astron. Soc., 403, L54-L58 (2010)>
=2010MNRAS.403L..54M 2010MNRAS.403L..54M
ADC_Keywords: Galaxies, photometry ; Ultraviolet ; Equivalent widths
Keywords: galaxies: evolution - galaxies: formation -
galaxies: individual: A1689-7.1 - cosmology: observations
Abstract:
We present the discovery of a large-scale structure of emission-line
galaxies at redshift z=4.86 behind a massive cluster of galaxies,
A1689. Previous spectroscopic observations of a galaxy, A1689-7.1 at
z=4.87, near this structure, revealed a possible overdense region of
intergalactic medium (IGM) around the galaxy, which extends at least
∼80 comoving Mpc along the line of sight. In order to investigate
whether this z∼5 IGM overdense region contains a galaxy overdensity,
we undertook narrow- and broad-band imaging observations around
A1689-7.1 with Subaru/Suprime-Cam. We detected 51 candidates as
Lyα emitters at redshift z=4.86±0.03 in the 32x24-arcmin2
field of view. After correction for lensing by the foreground cluster,
we found a large-scale (∼20x60 comoving Mpc) overdense region of
galaxies around A1689-7.1 in the source plane at z=4.86. The densest
peak in this region has an overdensity of δ∼4, suggesting that
this structure is probably a good candidate for a protocluster which
may evolve into a massive cluster of galaxies in the present-day
Universe. A1689-7.1 is located at the edge of this region, where the
local galaxy density is ∼1.6 times the mean density and is close to
the density contrast in the IGM along the line of sight to A1689-7.1
estimated from the optical depth. The overdensities of galaxies we
have found may suggest that at least some parts of the IGM overdense
region have already started to form galaxies and moreover they relate
to the formation of a protocluster. Although we lack information on
the three-dimensional distributions of both IGM and galaxy overdense
regions, the similarity of the scales of both regions may suggest that
the two are parts of a single large-scale structure, which would be an
large edge-on sheet along the line of sight with a size of ∼20x60x80
comoving Mpc.
Description:
We obtained narrow- and broad-band imaging centred at
(RA, DE)=13:11:29.5, -01:20:17 (J2000.0) on 2009 May 23-24 (UT)
using Suprime-Cam on the 8.2-m Subaru Telescope as an open use normal
programme (S09A-104). We also used archival V-band data of the same
field taken on 2001 April 24 (UT).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tables1.dat 85 51 Properties of the 51 candidate z=4.86 LAEs in
A1689 field
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See also:
J/A+A/498/13 : Lyman-α emitters from redshifts z∼2-3 (Nilsson+, 2009)
J/ApJ/706/762 : LAEs at z∼4.5 in the LALA Cetus field (Wang+, 2009)
J/ApJ/736/31 : HETDEX pilot survey. II. 1.9<z<3.8 LAEs (Blanc+, 2011)
J/ApJ/738/136 : LAEs between 0.19<z<1.25 with GALEX grism (Cowie+, 2011)
J/ApJ/743/9 : z=3.1 LAEs morphological properties (Gronwall+, 2011)
J/ApJ/744/110 : LAE galaxies between 2.1=<z≤3.1 (Ciardullo+, 2012)
J/ApJ/751/29 : Lyα profiles of LAEs at z=3.1 (Yamada+, 2012)
J/ApJ/753/95 : LAE galaxies in the ECDF-S at z∼2.1 and z∼3.1 (Bond+, 2012)
Byte-by-byte Description of file: tables1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- LAE Sequential number, [MRS2010] NN in Simbad (1)
4- 5 I2 h RAh Right ascension (J2000)
7- 8 I2 min RAm Right ascension (J2000)
10- 14 F5.2 s RAs Right ascension (J2000)
16 A1 --- DE- Declination sign (J2000)
17- 18 I2 deg DEd Declination (J2000)
20- 21 I2 arcmin DEm Declination (J2000)
23- 26 F4.1 arcsec DEs Declination (J2000)
28- 32 F5.1 arcsec oRAs Offset in right ascension (2)
34- 38 F5.1 arcsec oDEs Offset in declination (2)
40- 44 F5.2 mag NB711 [23.2/25.7] Subaru/NB711 magnitude (AB) (3)
46- 50 F5.2 mag Rimag Ri magnitude (7066Å) (AB) (3)
52- 56 F5.2 mag Vmag V magnitude (5447Å) (AB) (3)
58- 62 F5.2 mag Rmag R magnitude (6498Å) (AB) (3)
64- 68 F5.2 mag i'mag i' magnitude (7633Å) (AB) (3)
70- 74 F5.2 mag NB711i Intrinsic (unlensed) NB711 magnitude (AB)
76- 80 F5.2 [10-7W] logLLya Lymanα luminosity
82- 85 I4 0.1nm EWobs Observed Lymanα equivalent width (Å)
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Note (1): The LAEs are ranked in terms of intrinsic (unlensed) NB711
magnitude, NB711i.
Note (2): Offsets of LAEs in the source plane. The positive values show
offsets to East and North directions.
Note (3): Magnitudes below 1-σ are replaced by 1-σ upper limits.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 30-Sep-2014