J/A+A/647/A3 Abell 3391-Abell 3395 ASKAP/EMU image (Brueggen+, 2021)
Radio observations of the merging galaxy cluster system Abell 3391-Abell 3395.
Brueggen M., Reiprich T.H., Bulbul E., Koribalski B.S., Andernach H.,
Rudnick L., Hoang D.N., Wilber A.G., Duchesne S.W., Veronica A.,
Pacaud F., Hopkins A.M., Norris R.P., Johnston-Hollitt M., Brown M.J.I.,
Bonafede A., Brunetti G., Collier J.D., Sanders J.S., Vardoulaki E.,
Venturi T., Kapinska A.D., Marvil J.
<Astron. Astrophys. 647, A3 (2021)>
=2021A&A...647A...3B 2021A&A...647A...3B (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, galaxy ; Radio sources
Keywords: X-rays: galaxies: clusters - radio continuum: galaxies -
galaxies: clusters: intracluster medium
Abstract:
The pre-merging system of galaxy clusters Abell 3391-Abell 3395
located at a mean redshift of 0.053 has been observed at 1GHz in an
ASKAP/EMU Early Science observation as well as in X-rays with eROSITA.
The projected separation of the X-ray peaks of the two clusters is
∼50° or ∼3.1Mpc. Here we present an inventory of interesting radio
sources in this field around this cluster merger. While the eROSITA
observations provide clear indications of a bridge of thermal gas
between the clusters, neither ASKAP nor MWA observations show any
diffuse radio emission coinciding with the X-ray bridge. We derive an
upper limit on the radio emissivity in the bridge region of
1GHz<1.2x10-44W/H/m3. A non-detection of diffuse radio emission
in the X-ray bridge between these two clusters has implications for
particle-acceleration mechanisms in cosmological large-scale
structure. We also report extended or otherwise noteworthy radio
sources in the 30deg2 field around Abell 3391-Abell 3395. We
identified 20 Giant Radio Galaxies, plus 7 candidates, with linear
projected sizes greater than 1Mpc. The sky density of field radio
galaxies with largest linear sizes of >0.7Mpc is ∼1.7deg2, three
times higher than previously reported. We find no evidence for a
cosmological evolution of the population of Giant Radio Galaxies.
Moreover, we find seven candidates for cluster radio relics and radio
halos.
Description:
The A3391-A3395 system was observed as part of the Evolutionary Map of
the Universe (EMU) survey Early Science observations which use the new
ASKAP telescope in Australia to make a census of radio sources in the
sky south of +30° declination.
Our ASKAP observations reach a depth of 25-35uJy/beam root mean
square (rms) at a spatial resolution of 10-arcsec in the frequency
range 846.5-1134.5MHz.
Objects:
-----------------------------------------------
RA (2000) DE Designation(s)
-----------------------------------------------
06 26 15.4 -53 40 52 Abell 3391 = ACO 3391
06 27 31.1 -54 23 58 Abell 3395 = ACO 3395
-----------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
list.dat 120 1 Information of fits image
fits/* . 1 FITS image
--------------------------------------------------------------------------------
Byte-by-byte Description of file: list.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 24 I5 --- Nx Number of pixels along X-axis
26- 30 I5 --- Ny Number of pixels along Y-axis
32- 52 A21 "datime" Obs.date Observation date
54- 60 F7.5 GHz Freq Observed frequency
62- 67 I6 Kibyte size Size of FITS file
69-107 A39 --- FileName Name of FITS file, in subdirectory fits
109-120 A12 --- Title Title of the FITS file
--------------------------------------------------------------------------------
Acknowledgements:
Marcus Brueggen, mbrueggen(at)hs.uni-hamburg.de
(End) Patricia Vannier [CDS] 28-Nov-2020