The Multi-Wavelength Environment of Second Bologna Catalog Sources

A. Paggi; F. Massaro; H. Peña-Herazo; V. Missaglia; A. Jimenez-Gallardo; F. Ricci; S. Ettori; G. Giovannini; F. Govoni; R. D. Baldi; B. Mingo; M. Murgia; E. Liuzzo; F. Galati

arXiv · 2307.02541

The Multi-Wavelength Environment of Second Bologna Catalog Sources

A. Paggi·F. Massaro·H. Peña-Herazo·V. Missaglia·A. Jimenez-Gallardo·F. Ricci·S. Ettori·G. Giovannini·F. Govoni·R. D. Baldi·B. Mingo·M. Murgia·E. Liuzzo·F. Galati

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Abstract

We present the first results of the Chandra Cool Targets (CCT) survey of the Second Bologna Catalog (B2CAT) of powerful radio sources, aimed at investigating the extended X-ray emission surrounding these sources. For the first 33 sources observed in the B2CAT CCT survey, we performed both imaging and spectral X-ray analysis, producing multi-band Chandra images, and compared them with radio observations. To evaluate the presence of extended emission in the X-rays, we extracted surface flux profiles comparing them with simulated ACIS Point Spread Functions. We detected X-ray nuclear emission for 28 sources. In addition, we detected 8 regions of increased X-ray flux originating from radio hot-spots or jet knots, and a region of decreased flux, possibly associated with an X-ray cavity. We performed X-ray spectral analysis for 15 nuclei and found intrinsic absorption significantly larger than the Galactic values in four of them. We detected significant extended X-ray emission in five sources, and fitted their spectra with thermal models with gas temperatures $\sim 2 \text{ keV}$. In the case of B2.1 0742+31, the surrounding hot gas is compatible with the ICM of low luminosity clusters of galaxies, while the X-ray diffuse emission surrounding the highly disturbed WAT B2.3 2254+35 features a luminosity similar to those of relatively bright galaxy groups, although its temperature is similar to those of low luminosity galaxy clusters. These results highlight the power of the low-frequency radio selection, combined with short Chandra snapshot observations, to investigate the properties of the X-ray emission from radio sources.

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A. Paggi, F. Massaro, H. Peña-Herazo, V. Missaglia, A. Jimenez-Gallardo, F. Ricci, S. Ettori, G. Giovannini, F. Govoni, R. D. Baldi, B. Mingo, M. Murgia, E. Liuzzo, F. Galati. 2023-07-05. The Multi-Wavelength Environment of Second Bologna Catalog Sources. https://arxiv.org/abs/2307.02541

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