{
  "id": "2212.02061",
  "version": "v1",
  "published": "2022-12-05T06:51:45.000Z",
  "updated": "2022-12-05T06:51:45.000Z",
  "title": "Offsets between X-ray and Radio Components in X-ray Jets: The AtlasX",
  "authors": [
    "Karthik Reddy",
    "Markos Georganopoulos",
    "Eileen T. Meyer",
    "Mary Keenan",
    "Kassidy E. Kollman"
  ],
  "categories": [
    "astro-ph.HE",
    "astro-ph.GA"
  ],
  "abstract": "The X-ray emission mechanism of powerful extragalactic jets, which has important implications for their environmental impact, is poorly understood. The X-ray/radio positional offsets in individual features of jets provide important clues. Extending the previous work in Reddy et al. 2021, we present a detailed comparison between X-ray maps deconvolved using the Low Count Image Reconstruction and Analysis (LIRA) tool and radio maps of 164 components from 77 Chandra-detected X-ray jets. We detect 94 offsets (57%), with 58 new detections. In FR II-type jet knots, the X-rays peak and decay before the radio in about half the cases, disagreeing with the predictions of one-zone models. While a similar number of knots lack statistically significant offsets, we argue that projection and distance effects result in offsets below the detection level. Similar de-projected offsets imply that X-rays could be more compact than radio for most knots, and we qualitatively reproduce this finding with a \"moving-knot\" model. The bulk Lorentz factor derived for knots under this model is consistent with previous radio-based estimates, suggesting kpc-scale jets are only mildly relativistic. An analysis of X-ray/radio flux ratio distributions does not support the commonly invoked mechanism of X-ray production from inverse Compton scattering of the cosmic microwave background but does show a marginally significant trend of declining flux ratio as a function of distance from the core. Our results imply the need for multi-zone models to explain the X-ray emission from powerful jets. We provide an interactive list of our X-ray jet samples at http://astro.umbc.edu/Atlas-X.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2022-12-05T06:51:45.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "x-ray jet",
      "radio components",
      "low count image reconstruction",
      "x-ray/radio flux ratio distributions",
      "knots lack statistically significant offsets"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}