J/A+A/570/A55 Spiderweb galaxy 870um and 1.4GHz images (Dannerbauer+, 2014)
An excess of dusty starbursts related to the Spiderweb galaxy.
Dannerbauer H., Kurk J.D., De Breuck C., Wylezalek D., Santos J.S.,
Koyama Y., Seymour N., Tanaka M., Hatch N., Altieri B., Coia D.,
Galametz A., Kodama T., Miley G., Roettgering H., Sanchez-Portal M.,
Valtchanov I., Venemans B., Ziegler B.
<Astron. Astrophys., 570, A55-55 (2014)>
=2014A&A...570A..55D 2014A&A...570A..55D
ADC_Keywords: Galaxies, radio ; Millimetric/submm sources ; Radio sources
Keywords: galaxies: individual: MRC1138-262 -
galaxies: clusters: individual: MRC1138-262 -
galaxies: high-redshift - cosmology: observations -
infrared: galaxies - submillimeter: galaxies
Abstract:
We present APEX LABOCA 870µm observations of the field around the
high-redshift radio galaxy MRC1138-262 at z=2.16. We detect 16
submillimeter galaxies (SMGs) in this ∼140-arcmin2 bolometer map
with flux densities in the range 3-11mJy. The raw number counts
indicate a density of SMGs that is up to four times that of blank
field surveys. Based on an exquisite multiwavelength database,
including VLA 1.4 GHz radio and infrared observations, we investigate
whether these sources are members of the protocluster structure at
z≃2.2. Using Herschel PACS and SPIRE and Spitzer MIPS photometry, we
derive reliable far-infrared (FIR) photometric redshifts for all
sources. Follow-up VLT ISAAC and SINFONI NIR spectra confirm that four
of these SMGs have redshifts of z≃2.2. We also present evidence that
another SMG in this field, detected earlier at 850µm, has a
counterpart that exhibits Hα and CO(1-0) emission at z=2.15.
Including the radio galaxy and two SMGs with FIR photometric redshifts
at z=2.2, we conclude that at least eight submm sources are part of
the protocluster at z=2.16 associated with the radio galaxy
MRC1138-262. We measure a star formation rate density
SFRD∼1500M☉/yr/Mpc3, four magnitudes higher than the global
SFRD of blank fields at this redshift. Strikingly, these eight sources
are concentrated within a region of 2Mpc (the typical size of clusters
in the local universe) and are distributed within the filaments traced
by the HAEs at z≃2.2. This concentration of massive, dusty starbursts
is not centered on the submillimeter-bright radio galaxy which could
support the infalling of these sources into the cluster center.
Approximately half (6/11) of the SMGs that are covered by the Hα
imaging data are associated with HAEs, demonstrating the potential of
tracing SMG counterparts with this population. To summarize, our
results demonstrate that submillimeter observations may enable us to
study (proto)clusters of massive, dusty starbursts.
Description:
We provide both the APEX LABOCA 870um and the EVLA 1.4GHz signal
map of the field around the high-z radio galaxy MRC1138-262. In
addition, we make the integration and signal-to-noise map of the
LABOCA observations available. The LABOCA signal and S/N map are in
Jy, the integration map in seconds and the VLA 1.4GHz signal map is
in uJy.
Objects:
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RA (2000) DE Designation(s)
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11 40 48.3 -26 29 09 MRC1138-262 = Name Spiderweb galaxy
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 120 4 List of FITS images
fits/* . 4 Individual FITS images
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Name
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
26- 27 I2 deg DEd Declination (J2000)
29- 30 I2 arcmin DEm Declination (J2000)
32- 35 F4.1 arcsec DEs Declination (J2000)
37- 39 F3.1 arcsec/pix Scale [0.4/4] Scale of the image
41- 44 I4 --- Nx [244/2800] Number of pixels along X-axis
46- 49 I4 --- Ny [255/2800] Number of pixels along Y-axis
51- 55 I5 Kibyte size [250/30980] Size of FITS file
57- 87 A31 --- FileName Name of the FITS file in subdirectory fits
89-120 A32 --- Title Title of the file
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Acknowledgements:
Helmut Dannerbauer, helmut.dannerbauer(at)univie.ac.at
(End) Patricia Vannier [CDS] 25-Nov-2014