{"paper":{"title":"The first near-infrared high-resolution \\'echelle spectroscopy of the outflow in NGC 4151. A study of the clouds covering the Eye of Sauron","license":"http://creativecommons.org/licenses/by-nc-nd/4.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Enrico Piconcelli, Fabio La Franca, Francesco Gabriele Saturni, Hermine Landt, Matteo Perri, Riccardo Middei, Valerio D'Elia","submitted_at":"2026-05-26T17:59:03Z","abstract_excerpt":"We present the first high-resolution near-infrared spectroscopy of the nucleus of the nearby, well-known Seyfert galaxy NGC 4151 (the \"Eye of Sauron\"). Past studies of this source have revealed that it exhibits a variable absorption feature associated with the He I $\\lambda$10,830 AA emission line, potentially indicative of obscuration events affecting the central engine. Here, we take advantage of the IRTF/iSHELL and TNG/GIANO-B spectrographs to observe this feature with unprecedented spectral resolution ($\\lambda/\\Delta\\lambda > 50,000$), being able to study in detail the structure of the ab"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2605.27363","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/2605.27363/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"}