2002/08/28 by David Barrado y Navascues, D. Barrado, M. R. Zapatero Osorio +9 · 1 citation
Physics and Astronomy · #Accretion (finance) #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Binary number #Biology #Brown dwarf #Chromosphere #Cluster (spacecraft) #Emission spectrum #Geometry #H-alpha #Line (geometry) #Physics #Spectral line #Stars #Stellar, planetary, and galactic studies #Type (biology) #astro-ph
paper · pdf · doi:10.1051/0004-6361:20021251
published as Astron.Astrophys. 393 (2002) L85-L88 · Astronomy and Astrophysics Letters, accepted
arxiv created 2002/08/28 · openalex publication_date 2002/10/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report on the finding of the strongest Hα emission – pseudoequivalent width of 705 Å – known so far in a young, late type dwarf. This object, named as S Ori 71, is a substellar candidate member of the 1–8 Myr star cluster σ Orionis. Due to its overluminous location in color-magnitude diagrams, S Ori 71 might be younger than other cluster members, or a binary of similar components. Its mass is in the range 0.021–0.012 , depending on evolutionary models and possible binarity. The broad Hα line of S Ori 71 appears asymmetric, indicative of high velocity mass motions in the Hα forming region. The origin of this emission is unclear at the present time. We discuss three possible scenarios: accretion from a disk, mass exchange between the components of a binary system, and emission from a chromosphere.