{"paper":{"title":"X-ray investigation of possible super-Eddington accretion in a radio-loud quasar at $z=6.13$","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["astro-ph.HE"],"primary_cat":"astro-ph.GA","authors_text":"A. Caccianiga, A. Lupi, A. Moretti, B. Arsioli, C. Reynolds, C. Vignali, D. Dallacasa, E. Lambrides, F. Haardt, F. Pacucci, F. Rigamonti, F. Tavecchio, I. Matute, J. Afonso, James K. Leung, J. W. Broderick, L. Ighina, N. Seymour, P. Severgnini, R. Della Ceca, S. Belladitta, T. Connor","submitted_at":"2025-09-04T18:00:01Z","abstract_excerpt":"We present radio and X-ray observations of the recently discovered $z=6.13$ radio-powerful quasar RACS J032021.44$-$352104.1 using uGMRT, ATCA, LBA, and Chandra. The observed radio properties are in line with what is typically observed in high-$z$ radio quasars ($\\alpha_{\\rm r}=0.72\\pm 0.02$ and L$_{\\rm 1.4GHz}=5.8 \\pm 0.9 \\times 10^{26}$ W Hz$^{-1}$). Despite the relatively low X-ray flux observed $F_{\\rm 0.5-7.0 keV}=2.3\\pm0.5 \\times 10^{-14}$ erg sec$^{-1}$ cm$^{-2}$, the intrinsic luminosity in the 2-10 keV rest frame is markedly high, $L_{\\rm 2-10 keV}=1.8^{+1.1}_{-0.7} \\times 10^{46}$ er"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2509.04559","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2509.04559/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}