Show simple item record

High luminosity, slow ejecta and persistent carbon lines: SN 2009dc challenges thermonuclear explosion scenarios

Authordc.contributor.authorTaubenberger, S. 
Authordc.contributor.authorBenetti, S. es_CL
Authordc.contributor.authorChildress, M. es_CL
Authordc.contributor.authorPakmor, R. es_CL
Authordc.contributor.authorHachinger, S. es_CL
Authordc.contributor.authorMazzali, Paolo es_CL
Authordc.contributor.authorStanishev, V. es_CL
Authordc.contributor.authorElias-Rosa, Nancy es_CL
Authordc.contributor.authorAgnoletto, I. es_CL
Authordc.contributor.authorBufano, Filomena es_CL
Authordc.contributor.authorErgon, M. es_CL
Authordc.contributor.authorHarutyunyan, A. es_CL
Authordc.contributor.authorInserra, C. es_CL
Authordc.contributor.authorKankare, E. es_CL
Authordc.contributor.authorKromer, M. es_CL
Authordc.contributor.authorNavasardyan, H. es_CL
Authordc.contributor.authorNicolas, J. es_CL
Authordc.contributor.authorPastorello, A. es_CL
Authordc.contributor.authorProsperi, E. es_CL
Authordc.contributor.authorSalgado, F. es_CL
Authordc.contributor.authorSollerman, J. es_CL
Authordc.contributor.authorStritzinger, M. es_CL
Authordc.contributor.authorTuratto, M. es_CL
Authordc.contributor.authorValenti, S. es_CL
Authordc.contributor.authorHillebrandt, W. es_CL
Cita de ítemdc.identifier.citationMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY Volume: 412 Issue: 4 Pages: 2735-2762 Published: APR 2011es_CL
General notedc.descriptionArtículo de publicación ISIes_CL
Abstractdc.description.abstractExtended optical and near-IR observations reveal that SN 2009dc shares a number of similarities with normal Type Ia supernovae (SNe Ia), but is clearly overluminous, with a (pseudo-bolometric) peak luminosity of log (L) = 43.47 (erg s-1). Its light curves decline slowly over half a year after maximum light [delta m(15)(B)(true) = 0.71], and the early-time near-IR light curves show secondary maxima, although the minima between the first and the second peaks are not very pronounced. The bluer bands exhibit an enhanced fading after similar to 200 d, which might be caused by dust formation or an unexpectedly early IR catastrophe. The spectra of SN 2009dc are dominated by intermediate-mass elements and unburned material at early times, and by iron-group elements at late phases. Strong C ii lines are present until similar to 2 weeks past maximum, which is unprecedented in thermonuclear SNe. The ejecta velocities are significantly lower than in normal and even subluminous SNe Ia. No signatures of interaction with a circumstellar medium (CSM) are found in the spectra. Assuming that the light curves are powered by radioactive decay, analytic modelling suggests that SN 2009dc produced similar to 1.8 M-circle dot of 56Ni assuming the smallest possible rise time of 22 d. Together with a derived total ejecta mass of similar to 2.8 M-circle dot, this confirms that SN 2009dc is a member of the class of possible super-Chandrasekhar-mass SNe Ia similar to SNe 2003fg, 2006gz and 2007if. A study of the hosts of SN 2009dc and other superluminous SNe Ia reveals a tendency of these SNe to explode in low-mass galaxies. A low metallicity of the progenitor may therefore be an important prerequisite for producing superluminous SNe Ia. We discuss a number of possible explosion scenarios, ranging from super-Chandrasekhar-mass white-dwarf progenitors over dynamical white-dwarf mergers and Type I<file name="mnr_18107_mu1.gif" type="gif"/> SNe to a core-collapse origin of the explosion. None of the models seems capable of explaining all properties of SN 2009dc, so that the true nature of this SN and its peers remains nebulous.es_CL
Patrocinadordc.description.sponsorshipastronomers at the Telescopio Nazionale Galileo 2.2-m Telescope at Calar Alto Nordic Optical Telescope Large Binocular Telescope National Aeronautics and Space Administration Lyon-Meudon Extragalactic Database (LEDA) Alfred P. Sloan Foundation National Science Foundation US Department of Energy Japanese Monbukagakusho Max Planck Society Higher Education Funding Council for England Transregional Collaborative Research Centre TRR 33 Office of Science, Office of High Energy Physics, of the US Department of Energy DE-AC02-05CH11231 Gordon & Betty Moore Foundation PRIN-INAF Fundacao para a Ciencia e a Tecnologiaes_CL
Keywordsdc.subjectsupernovae: generales_CL
Títulodc.titleHigh luminosity, slow ejecta and persistent carbon lines: SN 2009dc challenges thermonuclear explosion scenarioses_CL
Document typedc.typeArtículo de revistaes_CL

Files in this item


This item appears in the following Collection(s)

Show simple item record