{"paper":{"title":"Reference star differential imaging of close-in companions and circumstellar disks with the NIRC2 vortex coronagraph at W.M. Keck Observatory","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.EP","physics.optics"],"primary_cat":"astro-ph.IM","authors_text":"Carlos Gomez Gonzalez, Dimitri Mawet, Elodie Choquet, Elsa huby, Eugene Serabyn, Garreth Ruane, Henry Ngo, Keith Matthews, Maddalena Reggiani, Nicole Wallack, Olivier Absil, Therese Cook, Tiffany Meshkat, W. Jerry Xuan","submitted_at":"2019-01-13T23:50:07Z","abstract_excerpt":"Reference star differential imaging (RDI) is a powerful strategy for high contrast imaging. Using example observations taken with the vortex coronagraph mode of Keck/NIRC2 in $L^\\prime$ band, we demonstrate that RDI provides improved sensitivity to point sources at small angular separations compared to angular differential imaging (ADI). Applying RDI to images of the low-mass stellar companions HIP 79124 C (192 mas separation, $\\Delta L^\\prime$=4.01) and HIP 78233 B (141 mas separation, $\\Delta L^\\prime$=4.78), the latter a first imaging detection, increases the significance of their detection"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.04090","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"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"}