title: Astronomy. ASASSN-15lh: A highly super-luminous supernova.
abstract: We report the discovery of ASASSN-15lh (SN 2015L), which we interpret as the most luminous supernova yet found. At redshift z = 0.2326, ASASSN-15lh reached an absolute magnitude of Mu ,AB = -23.5 ± 0.1 and bolometric luminosity Lbol = (2.2 ± 0.2) × 10(45) ergs s(-1), which is more than twice as luminous as any previously known supernova. It has several major features characteristic of the hydrogen-poor super-luminous supernovae (SLSNe-I), whose energy sources and progenitors are currently poorly understood. In contrast to most previously known SLSNe-I that reside in star-forming dwarf galaxies, ASASSN-15lh appears to be hosted by a luminous galaxy (MK ≈ -25.5) with little star formation. In the 4 months since first detection, ASASSN-15lh radiated (1.1 ± 0.2) × 10(52) ergs, challenging the magnetar model for its engine.
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authors.affiliation: Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210, USA. Center for Cosmology and AstroParticle Physics (CCAPP), The Ohio State University, 191 W. Woodruff Avenue, Columbus, OH 43210, USA.
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authors.affiliation: Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210, USA. Center for Cosmology and AstroParticle Physics (CCAPP), The Ohio State University, 191 W. Woodruff Avenue, Columbus, OH 43210, USA.
authors.forename: T W-S
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authors.affiliation: Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210, USA. Center for Cosmology and AstroParticle Physics (CCAPP), The Ohio State University, 191 W. Woodruff Avenue, Columbus, OH 43210, USA.
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authors.affiliation: Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210, USA. Center for Cosmology and AstroParticle Physics (CCAPP), The Ohio State University, 191 W. Woodruff Avenue, Columbus, OH 43210, USA.
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authors.affiliation: Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210, USA.
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authors.affiliation: Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210, USA. Center for Cosmology and AstroParticle Physics (CCAPP), The Ohio State University, 191 W. Woodruff Avenue, Columbus, OH 43210, USA. Department of Physics, The Ohio State University, 191 W. Woodruff Avenue, Columbus, OH 43210, USA.
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authors.affiliation: Department of Earth and Space Science, Morehead State University, 235 Martindale Drive, Morehead, KY 40351, USA.
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authors.affiliation: Millennium Institute of Astrophysics, Santiago, Chile. Departamento Ciencias Fisicas, Universidad Andres Bello, Av. Republica 252, Santiago, Chile.
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authors.affiliation: Department of Astronomy, The Ohio State University, 140 W. 18th Avenue, Columbus, OH 43210, USA.
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