X-Ray-to-Radio Offset Inference from Low-Count X-Ray Jets
| dc.contributor.author | Reddy, Karthik | |
| dc.contributor.author | Georganopoulos, Markos | |
| dc.contributor.author | Meyer, Eileen T. | |
| dc.date.accessioned | 2021-02-08T16:36:00Z | |
| dc.date.available | 2021-02-08T16:36:00Z | |
| dc.description.abstract | Observations of positional offsets between the location of X-ray and radio features in many resolved, extragalactic jets indicates that the emitting regions are not co-spatial, an important piece of evidence in the debate over the origin of the X-ray emission on kpc scales. The existing literature is nearly exclusively focused on jets with sufficiently deep \emph{Chandra} observations to yield accurate positions for X-ray features, but most of the known X-ray jets are detected with tens of counts or fewer, making detailed morphological comparisons difficult. Here we report the detection of X-ray-to-radio positional offsets in 15 extragalactic jets from an analysis of 22 sources with low-count \textit{Chandra} observations, where we utilized the Low-count Image Reconstruction Algorithm (LIRA). This algorithm has allowed us to account for effects such as Poisson background fluctuations and nearby point sources which have previously made the detection of offsets difficult in shallow observations. Using this method, we find that in 55 \% of knots with detectable offsets, the X-rays peak upstream of the radio, questioning the applicability of one-zone models, including the IC/CMB model for explaining the X-ray emission. We also report the non-detection of two previously claimed X-ray jets. Many, but not all, of our sources, follow a loose trend of increasing offset between the X-ray and radio emission, as well as a decreasing X-ray to radio flux ratio along the jet. | en_US |
| dc.description.sponsorship | We thank Dr. Vinay L. Kashyap for valuable suggestions on computing the offsets using output images from LIRA. We acknowledge financial support from the National Science Foundation under Grant No. 1714380. The scientific results reported in this article are based in part on observations made by the Chandra X-ray Observatory and data obtained from the Chandra Data Archive. This research has made use of software provided by the Chandra X-ray Center (CXC) in the application packages CIAO, ChIPS, and Sherpa. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. The Australia Telescope Compact Array is part of the Australia Telescope National Facility which is funded by the Australian Government for operation as a National Facility managed by CSIRO. We acknowledge the Gomeroi people as the traditional owners of the Observatory site. This research is based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555. | en_US |
| dc.description.uri | https://arxiv.org/abs/2101.02024 | en_US |
| dc.format.extent | 56 pages | en_US |
| dc.genre | journal articles preprints | en_US |
| dc.identifier | doi:10.13016/m2fl1d-adpp | |
| dc.identifier.citation | Karthik Reddy, Markos Georganopoulos and Eileen T. Meyer, X-Ray-to-Radio Offset Inference from Low-Count X-Ray Jets, https://arxiv.org/abs/2101.02024 | en_US |
| dc.identifier.uri | http://hdl.handle.net/11603/20971 | |
| dc.language.iso | en_US | en_US |
| dc.relation.isAvailableAt | The University of Maryland, Baltimore County (UMBC) | |
| dc.relation.ispartof | UMBC Physics Department Collection | |
| dc.relation.ispartof | UMBC Student Collection | |
| dc.relation.ispartof | UMBC Faculty Collection | |
| dc.rights | This item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author. | |
| dc.rights | Attribution 4.0 International | * |
| dc.rights.uri | https://creativecommons.org/licenses/by/4.0/ | * |
| dc.title | X-Ray-to-Radio Offset Inference from Low-Count X-Ray Jets | en_US |
| dc.type | Text | en_US |