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![Unbinned Chandra photon-image in the [0.5-2] keV band of cluster IRC-0218A for a total exposure time of ∼ 84 ks. The blue circle indicates the position of the main cluster component (A) as inferred from the Spitzer and XMM data. The two red circles (B1, B2) indicate point sources in the vicinity of a possible second cluster component as proposed by Tanaka et al. (2010).](profile/Florian-Pacaud/publication/51940778/figure/fig1/AS:650520050032647@1532107474787/Unbinned-Chandra-photon-image-in-the-05-2-keV-band-of-cluster-IRC-0218A-for-a-total.png)
Unbinned Chandra photon-image in the [0.5-2] keV band of cluster IRC-0218A for a total exposure time of ∼ 84 ks. The blue circle indicates the position of the main cluster component (A) as inferred from the Spitzer and XMM data. The two red circles (B1, B2) indicate point sources in the vicinity of a possible second cluster component as proposed by Tanaka et al. (2010).
Source publication
![Fig. 1. Unbinned Chandra photon-image in the [0.5-2] keV band of...](profile/Florian-Pacaud/publication/51940778/figure/fig1/AS:650520050032647@1532107474787/Unbinned-Chandra-photon-image-in-the-05-2-keV-band-of-cluster-IRC-0218A-for-a-total_Q320.jpg)
![Fig. 4. The Chandra data ([0.3-2] keV band) around the cluster main...](profile/Florian-Pacaud/publication/51940778/figure/fig2/AS:650520050012185@1532107474913/The-Chandra-data-03-2-keV-band-around-the-cluster-main-component-A-smoothed-by-a_Q320.jpg)
![Fig. 6. Growth curve of source A, from the XMM image in the [0.5-2] keV...](profile/Florian-Pacaud/publication/51940778/figure/fig6/AS:668670091067400@1536434781588/Growth-curve-of-source-A-from-the-XMM-image-in-the-05-2-keV-band-dilution-effect-by_Q320.jpg)
Context: Very few z > 1.5 clusters of galaxies are known. It is important to
study the properties of galaxies in these clusters and the ICM and, further, to
cross-check the reliability of the various mass estimates. This will help to
clarify the process of structure formation and how distant clusters may be used
to constrain cosmology. AIMS: We pre...
Contexts in source publication
Context 1
... with Chandra ACIS-S (obsid 12882). The data were reduced fol- lowing the standard procedures using the Chandra Interactive Analysis of Observations CIAO version 4.3 and CALDB ver- sion 4.4.2 ( Fruscione et al. (2006)). After cleaning and filtering, the good time remaining was 83.7 ks. The photon image of the cluster field is presented on Fig. 1. At the position of the main cluster and of the companion, bright point sources are detected while no extended emission is conspicuous. For comparison, the XMM image is shown on Fig. 2. The sources all show a tangen- tial elongation typical of the XMM PSF at large off axis angle, suggesting that they are in large part indeed ...
Context 2
... restricting the Chandra measurement to the point-source itself gives 1.6 Fig. 2. The XMM image of IRC-0218A is a composite of 3 adjacent observations; the resulting mean off-axis distance is ∼ 12 ′ . Left: the photon image adaptively smoothed (boxcar smoothing with minimum threshold of 10 photons). The position of the 3 Chandra point sources (Fig. 1) is indicated by circles having a radius of 25 ′′ . Right: The merged exposure map; the colour scale indicates the cumulative effective exposure. Fig. 3. Chandra contours in the [0.5-2] keV band, overlaid on a R-z-3.5µm image of the cluster. The two green circles indicate the X-ray sources for which a spectroscopic redshift is ...
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Citations
... Lotz et al. (2013) reported that the galaxy merger rate in the protocluster IRC-0218A at = 1.62 was 3-10 times higher compared to the general fields at the same epoch. This protocluster exhibits a high overdensity factor of 20 and a low velocity dispersion of 360 ± 90 km s −1 (Pierre et al. 2012), being dynamically cold and therefore favorable for galaxy mergers. Conversely, Monson et al. (2021) found no enhancement in the protocluster SSA22 at = 3.09 due to limited HST observations. ...
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