2013ApJ...779..189F


C.D.S. - SIMBAD4 rel 1.7 - 2021.05.15CEST23:42:22

2013ApJ...779..189F - Astrophys. J., 779, 189 (2013/December-3)

Discovery of megaparsec-scale, low surface brightness nonthermal emission in merging galaxy clusters using the green bank telescope.

FARNSWORTH D., RUDNICK L., BROWN S. and BRUNETTI G.

Abstract (from CDS):

We present results from a study of 12 X-ray bright clusters at 1.4 GHz with the 100 m Green Bank Telescope. After subtraction of point sources using existing interferometer data, we reach a median (best) 1σ rms sensitivity level of 0.01 (0.006) µJy/arcsec2, and find a significant excess of diffuse, low surface brightness emission in 11 of 12 Abell clusters observed. We also present initial results at 1.4 GHz of A2319 from the Very Large Array. In particular, we find: (1) four new detections of diffuse structures tentatively classified as two halos (A2065, A2069) and two relics (A2067, A2073); (2) the first detection of the radio halo in A2061 at 1.4 GHz, which qualifies this as a possible ultra-steep spectrum halo source with a synchrotron spectral index of α ∼ 1.8 between 327 MHz and 1.4 GHz; (3) a ∼2 Mpc radio halo in the sloshing, minor-merger cluster A2142; (4) a >2x increase of the giant radio halo extent and luminosity in the merging cluster A2319; (5) a ∼7x increase to the integrated radio flux and >4x increase to the observed extent of the peripheral radio relic in A1367 to ∼600 kpc, which we also observe to be polarized on a similar scale; (6) significant excess emission of ambiguous nature in three clusters with embedded tailed radio galaxies (A119, A400, A3744). Our radio halo detections agree with the well-known X-ray/radio luminosity correlation, but they are larger and fainter than current radio power correlation studies would predict. The corresponding volume-averaged synchrotron emissivities are 1-2 orders of magnitude below the characteristic value found in previous studies. Some of the halo-like detections may be some type of previously unseen, low surface brightness radio halo or blend of unresolved shock structures and sub-Mpc-scale turbulent regions associated with their respective cluster merging activity. Four of the five tentative halos contain one or more X-ray cold fronts, suggesting a possible connection between gas sloshing and particle acceleration on large scales in some of these clusters. Additionally, we see evidence for a possible inter-cluster filament between A2061 and A2067. For our faintest detections, we note the possibility of residual contamination from faint radio galaxies not accounted for in our confusion subtraction procedure. We also quantify the sensitivity of the NVSS to extended emission as a function of size.

Abstract Copyright:

Journal keyword(s): galaxies: clusters: intracluster medium - intergalactic medium

Simbad objects: 25

goto Full paper

goto View the reference in ADS

Number of rows : 25

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 ACO 119 ClG 00 56 16.8 -01 15 00           ~ 531 2
2 UGC 595 AGN 00 57 34.904589 -01 23 27.55141   14.07 15.10     ~ 235 1
3 ACO 400 ClG 02 57 37.4 +06 00 45           ~ 387 3
4 3C 75 PaG 02 57 41.64 +06 01 28.0           ~ 287 1
5 ACO 399 ClG 02 57 56.4 +13 00 59           ~ 357 0
6 ACO 401 ClG 02 58 56.9 +13 34 56           ~ 528 0
7 ACO 521 ClG 04 54 08.6 -10 14 39           ~ 218 0
8 ACO 1213 ClG 11 16 29.1 +29 15 37           ~ 147 0
9 ACO 1367 ClG 11 44 44.6 +19 41 59           ~ 1008 1
10 3C 264.0 QSO 11 45 05.0090520 +19 36 22.741257   14.98 13.97     ~ 550 2
11 ACO 1656 ClG 12 59 48.7 +27 58 50           ~ 4351 2
12 3C 286 Sy1 13 31 08.2885060664 +30 30 32.960825107   17.51 17.25     ~ 3866 2
13 ACO 2056 ClG 15 19 12 +28 16.2           ~ 48 0
14 ACO 2061 ClG 15 21 20.58 +30 40 15.3           ~ 168 1
15 ACO 2065 ClG 15 22 42.6 +27 43 21           ~ 348 0
16 ACO 2067 ClG 15 23 14 +30 54.4           ~ 102 1
17 ACO 2069 ClG 15 23 57.9 +29 53 26           ~ 125 0
18 NAME Corona Borealis SCG 15 25 +29.5           ~ 117 0
19 ACO 2073 ClG 15 25 41 +28 24.5           ~ 28 0
20 ACO 2142 ClG 15 58 20.00 +27 14 00.3           ~ 693 0
21 ACO 2255 ClG 17 12 50.04 +64 03 10.6           ~ 519 0
22 ACO 2319 ClG 19 20 45.3 +43 57 43           ~ 424 1
23 ACO 3744 ClG 21 07 13.8 -25 28 54           ~ 75 1
24 NGC 7016 BiC 21 07 16.289 -25 28 08.04   14.87       ~ 32 1
25 NGC 7018 IG 21 07 25.7 -25 25 46   14.37 16.8     ~ 75 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2013ApJ...779..189F and select 'bookmark this link' or equivalent in the popup menu


2021.05.15-23:42:22

© Université de Strasbourg/CNRS

    • Contact