The Type IIb Supernova 2011dh from a Supergiant Progenitor

BERSTEN, MELINA C.; BENVENUTO, OMAR G.; NOMOTO, KEN'ICHI; ERGON, MATTIAS; FOLATELLI, GASTÓN; SOLLERMAN, JESPER; BENETTI, STEFANO; BOTTICELLA, MARIA TERESA; FRASER, MORGAN; KOTAK, RUBINA; MAEDA, KEIICHI; OCHNER, PAOLO; TOMASELLA, LINA

ASTROPHYSICAL JOURNAL

IOP PUBLISHING LTD

Lugar: Londres; Año: 2012 vol. 757 p. 31 - 40

0004-637X

A set of hydrodynamical models based on stellar evolutionary progenitors is used to study the nature of SN 2011dh. Our modeling suggests that a large progenitor star—with R ~ 200 R ⊙—is needed to reproduce the early light curve (LC) of SN 2011dh. This is consistent with the suggestion that the yellow super-giant star detected at the location of the supernova (SN) in deep pre-explosion images is the progenitor star. From the main peak of the bolometric LC and expansion velocities, we constrain the mass of the ejecta to be ≈2 M ⊙, the explosion energy to be E = (6-10) × 1050 erg, and the 56Ni mass to be approximately 0.06 M ⊙. The progenitor star was composed of a helium core of 3-4 M ⊙ and a thin hydrogen-rich envelope of ≈0.1M ⊙ with a main-sequence mass estimated to be in the range of 12-15 M ⊙. Our models rule out progenitors with helium-core masses larger than 8 M ⊙, which correspond to M ZAMS >~ 25M ⊙. This suggests that a single star evolutionary scenario for SN 2011dh is unlikely.