{"paper":{"title":"Is Draco II one of the faintest dwarf galaxies? First study from Keck/DEIMOS spectroscopy","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Annette M. N. Ferguson, Benjamin P. M. Laevens, Christopher Waters, Eric F. Bell, Hans-Walter Rix, Kenneth C. Chambers, Marla Geha, Michelle L. M. Collins, Nicolas F. Martin, Richard J. Wainscoat, Rodrigo A. Ibata","submitted_at":"2015-10-05T20:09:53Z","abstract_excerpt":"We present the first spectroscopic analysis of the faint and compact stellar system Draco II (Dra II, M_V=-2.9+/-0.8, r_h=19^{+8}_{-6} pc), recently discovered in the Pan-STARRS1 3{\\pi} survey. The observations, conducted with DEIMOS on the Keck II telescope, establish some of its basic characteristics: the velocity data reveal a narrow peak with 9 member stars at a systemic heliocentric velocity <v_r>=-347.6^{+1.7}_{-1.8} km/s, thereby confirming Dra II is a satellite of the Milky Way; we infer a velocity dispersion with \\sigma_{vr}=2.9+/-2.1 km/s (<8.4 km/s at the 95% confidence level), whic"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1510.01326","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"}