Fig 5 - uploaded by Somak Raychaudhury
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Multiband false-color image of the Double Irony: X-ray emission in blue displayed at the noise level, optical emission (i-band image from the CFHT) in green, radio emission from the GMRT at 610 MHz as yellow contours.
Source publication
We show how the XXL multiwavelength survey can be used to shed light on radio galaxies and their environment. Two prominent radio galaxies were identified in a visual examination of the mosaic of XXL-North obtained with the Giant Metrewave Radio Telescope at 610MHz. Counterparts were searched for in other bands. Spectroscopic redshifts from the GAM...
Contexts in source publication
Context 1
... closer inspection of the X-ray image (Fig. 5) does not re- veal any clear extended emission. The noise varies across the image and the quality of the data does not allow us to say any- thing about the presence or absence of gas interaction with the radio ...
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... Fig. 6 we show the radio images of the Double Irony. The structure of the source is best seen in the GMRT 610 MHz im- age that combines high angular resolution and good sensitivity. 20 The yellow cross indicates the location of the center of the host galaxy. Several features appear clearly in this image: the central east-west jets, a bright lobe to the southwest, a diffuse plume farther out (SW2), a bright region to the northeast (known as the "Elbow"), and a second diffuse plume-like feature to the north that breaks into several lumps. These five main features are also seen in the lower resolution (45 ) 1.4 GHz image from the NVSS. The higher resolution FIRST image at the same fre- quency is badly affected by stripes that prevent us from seeing the two plumes in the north and the southwest. The TGSS ADR1 image is noisy as well. Only the lobe in the SW1 region is clearly visible. While the lumps of emission in the north and in the El- 20 The Double Irony lies in the northwestern corner of the GMRT 610 MHz mosaic at the intersection of two pointings where the noise is slightly higher than average (see Fig. 5 of XXL Paper XXIX). Most striking perhaps are the multiple bends: on the eastern side the nearly horizontal jet turns abruptly, but remains colli- mated until the bright Elbow; the continued structure to the north of the Elbow is fainter and at about 90 degrees from its original direction. On the SW side, the jet shows a small deviation be- fore entering the SW1 lobe, and the SW2 plume is at another angle. The entire structure covers about 4 and shows a remark- able symmetry by rotation of 180 degrees, which suggests that it is not a superposition of several sources, but forms one system. We examined optical images and could not find any counterparts to the individual features described ...
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... the Exemplar's cluster (XLSSC 112), the difference in the r-band magnitude is 0.97, while for the BCG of the Double Irony group it is much lower, 0.35. The second brightest galaxy in the Double Irony environment is a late-type galaxy located near the Elbow radio structure (see Fig. 5 and Sect. 4.4.2). The Exemplar has M r = −22.73 and the Double Irony has M r = −22.85. Placing them in the diagram of Raouf et al., we see that the Double Irony group has a higher probability of being a young galaxy group (box (3) with 63% probability of being young and 4% probability of being old). The Exemplar group, XLSSC 112, falls in box (7) with a 30% probability of being young and a 22% probability of being old. This means that the probability that the Exemplar's cluster is older that the Double Irony's group/cluster is 51%, while the probability that the Double Irony is older than the Exemplar is 13%; there is a 36% probability that they are in the same age group (young, old, or in between). While this is not conclusive in itself, it is consistent with the idea that the Double Irony's group/cluster is not as evolved as XLSSC ...
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... closer inspection of the X-ray image (Fig. 5) does not reveal any clear extended emission. The noise varies across the image and the quality of the data does not allow us to say anything about the presence or absence of gas interaction with the radio ...
Context 5
... in the north and the southwest. The TGSS ADR1 image is noisy as well. Only the lobe in the SW1 region is clearly visible. While the lumps of emission in the north and in the El- 20 The Double Irony lies in the northwestern corner of the GMRT 610 MHz mosaic at the intersection of two pointings where the noise is slightly higher than average (see Fig. 5 of XXL Paper XXIX). Most striking perhaps are the multiple bends: on the eastern side the nearly horizontal jet turns abruptly, but remains collimated until the bright Elbow; the continued structure to the north of the Elbow is fainter and at about 90 degrees from its original direction. On the SW side, the jet shows a small deviation ...
Context 6
... the Exemplar's cluster (XLSSC 112), the difference in the r-band magnitude is 0.97, while for the BCG of the Double Irony group it is much lower, 0.35. The second brightest galaxy in the Double Irony environment is a late-type galaxy located near the Elbow radio structure (see Fig. 5 and Sect. 4.4.2). The Exemplar has M r = −22.73 and the Double Irony has M r = −22.85. Placing them in the diagram of Raouf et al., we see that the Double Irony group has a higher probability of being a young galaxy group (box (3) with 63% probability of being young and 4% probability of being old). The Exemplar group, XLSSC 112, falls ...
