J/A+A/461/823 Candidate Lyα emitting galaxies (Venemans+, 2007)
Protoclusters associated with z > 2 radio galaxies.
I. Characteristics of high redshift protoclusters.
Venemans B.P., Roettgering H.J.A., Miley G.K., van Breugel W.J.M.,
De Breuck C., Kurk J.D., Pentericci L., Stanford S.A., Overzier R.A.,
Croft S., Ford H.
<Astron. Astrophys., 461, 823-845 (2007)>
=2007A&A...461..823V 2007A&A...461..823V
ADC_Keywords: Galaxies, radio ; Active gal. nuclei ; Redshifts
Keywords: galaxies: active - galaxies: clusters: general -
cosmology: observations - cosmology: early Universe -
cosmology: large scale structure of Universe
Abstract:
We present the results of a large program conducted with the Very
Large Telescope and augmented by observations with the Keck telescope
to search for forming clusters of galaxies near powerful radio
galaxies at 2.0<z<5.2. Besides MRC 1138-262 at z=2.16, the radio
galaxy observed in our pilot program, we obtained narrow- and
broad-band images of eight radio galaxies and their surroundings. The
imaging was used to select candidate Lyα emitting galaxies in
∼3x3Mpc2 areas near the radio galaxies. A total of 300 candidate
emitters were found with a rest-frame Lyα equivalent width of
EW0>15Å and significance Sigma{equiv.to}(EW0/DEW0)>3. Follow-up
spectroscopy was performed on 152 candidates in seven of the radio
galaxy fields. Of these, 139 were confirmed to be Lyα emitters,
four were low redshift interlopers and nine were non-detections. With
the adopted criteria the success rate is 139/152=91%. In addition, 14
objects with EW0<15 and/or Sigma<3 were confirmed to be Lyα
emitters. Combined with the 15 Lyα emitters near MRC 1138-262,
we have determined Lyα redshifts for 168 objects near eight
radio galaxies.
Description:
All the narrow-band imaging and most of the broad-band imaging
obtained in the large program were performed with the FOcal
Reducer/low dispersion Spectrograph 2 (FORS2) in imaging mode between
2001 Mar 24 and 2002 Sep 08.
Additional (broad-band) imaging was obtained using the Low Resolution
Imaging Spectrometer (LRIS) on the Keck I telescope between 2003 Jan
31 and 2004 Jan 19.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 63 9 Details of the radio galaxies observed
tablea1.dat 89 4 Position and properties of the Lyα emission
line of the confirmed Lyα emitters and
the radio galaxy in the 2048 field
tablea2.dat 89 38 Position and properties of the Lyα emission
line of the confirmed Lyα emitters and
the radio galaxy in the 0052 field
tablea3.dat 89 29 Position and properties of the Lyα emission
line of the confirmed Lyα emitters and
the radio galaxy in the 0943 field
tablea4.dat 89 12 Position and properties of the Lyα emission
line of the confirmed Lyα emitters and
the radio galaxy in the 2009 field
tablea5.dat 89 38 Position and properties of the Lyα emission
line of the confirmed Lyα emitters and
the radio galaxy in the two 1338 fields
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See also:
J/ApJ/614/75 : Lymanα emitting galaxies at z=2.38 (Francis+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Name Radio galaxy name
17- 18 I2 h RAh Right ascension (J2000)
20- 21 I2 min RAm Right ascension (J2000)
23- 26 F4.1 s RAs Right ascension (J2000)
28 A1 --- DE- Declination sign (J2000)
29- 30 I2 deg DEd Declination (J2000)
32- 33 I2 arcmin DEm Declination (J2000)
35- 38 F4.1 arcsec DEs Declination (J2000)
40- 43 F4.2 --- z Redshift
45- 51 E7.2 mW/m2/sr RLum Radio luminosity at a rest-frame frequency
of 2.7GHz
53- 63 A11 --- FileName Name of the table with the Lyα emitters
around the radio galaxy
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Byte-by-byte Description of file: tablea?.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- [VRM2007] Lyα emission designation, HHMM.LAENN,
or galaxy name, HHMM.RG (1)
13- 14 I2 h RAh Right ascension (J2000)
16- 17 I2 min RAm Right ascension (J2000)
19- 23 F5.2 s RAs Right ascension (J2000)
25 A1 --- DE- Declination sign (J2000)
26- 27 I2 deg DEd Declination (J2000)
29- 30 I2 arcmin DEm Declination (J2000)
32- 35 F4.1 arcsec DEs Declination (J2000)
37- 42 F6.4 --- z Redshift
44- 49 F6.4 --- e_z rms uncertainty on z
51- 58 E8.3 mW/m2 Flux Lyα flux
60- 67 E8.3 mW/m2 e_Flux rms uncertainty on Flux
69- 71 I3 0.1nm EW0 Rest-frame equivalent width of Lyα line
73- 76 I4 0.1nm E_EW0 Error on EW0 (upper limit)
78- 79 I2 0.1nm e_EW0 Error on EW0 (lower limit)
81 A1 --- l_FWHM Limit flag on FWHM
82- 85 I4 km/s FWHM Lyα FWHM
87- 89 I3 km/s e_FWHM ? rms uncertainty on FWHM
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Note (1): Nomenclature note:
tablea1 = [VRM2007] 2048.LAENN in Simbad
tablea2 = [VRM2007] 0052.LAENN in Simbad
tablea3 = [VRM2007] 0943.LAENN in Simbad
tablea4 = [VRM2007] J2009.LAENN in Simbad
tablea5 = [VRM2007] J1338.LAENN in Simbad
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 03-Sep-2007