ON THE PROGENITOR OF THE TYPE II-PLATEAU SN 2008cn in NGC 4603

Journal Article · Tue Dec 01 04:00:00 EST 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/706/2/1174· OSTI ID:21378076

Elias-Rosa, Nancy; Van Dyk, Schuyler D ^[1]; Li, Weidong; Filippenko, Alexei V; Foley, Ryan J; Smith, Nathan ^[2]; Morrell, Nidia; Gonzalez, Sergio ^[3]; Hamuy, Mario ^[4]; Cuillandre, Jean-Charles ^[5]

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1. Spitzer Science Center, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125, USA. (United States)
2. Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)
3. Las Campanas Observatory, Carnegie Observatories, Casilla 601, La Serena (Chile)
4. Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago (Chile)
5. Canada France-Hawaii Telescope Corporation, 65-1238 Mamalahoa Hwy, Kamuela, HI 96743 (United States)

A trend is emerging regarding the progenitor stars that give rise to the most common core-collapse supernovae (SNe), those of Type II-Plateau (II-P): they generally appear to be red supergiants with a limited range of initial masses, approx8-16 M{sub sun}. Here, we consider another example, SN 2008cn, in the nearly face-on spiral galaxy NGC 4603. Even with limited photometric data, it appears that SN 2008cn is not a normal SN II-P, but is of the high-luminosity subclass. Through comparison of pre- and post-explosion images obtained with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope, we have isolated a supergiant star prior to explosion at nearly the same position as the SN. We provide evidence that this supergiant may well be the progenitor of the SN, although this identification is not entirely unambiguous. This is exacerbated by the distance to the host galaxy, 33.3 Mpc, making SN 2008cn the most distant SN II-P yet for which an attempt has been made to identify a progenitor star in pre-SN images. The progenitor candidate has a more yellow color ([V - I]{sub 0} = 0.98 mag and T {sub eff} = 5200 +- 300 K) than generally would be expected and, if a single star, would require that it exploded during a 'blue loop' evolutionary phase, which is theoretically not expected to occur. Nonetheless, we estimate an initial mass of M{sub ini} = 15 +- 2 M{sub sun} for this star, which is within the expected mass range for SN II-P progenitors. The yellower color could also arise from the blend of two or more stars, such as a red supergiant and a brighter, blue supergiant. Such a red supergiant hidden in this blend could instead be the progenitor and would also have an initial mass within the expected progenitor mass range. Furthermore, the yellow supergiant could be in a massive, interacting binary system, analogous to the possible yellow supergiant progenitor of the high-luminosity SN II-P 2004et. Finally, if the yellow supergiant is not the progenitor, or is not a stellar blend or binary containing the progenitor, then we constrain any undetected progenitor star to be a red supergiant with M{sub ini} approx< 11 M{sub sun}, considering a physically more realistic scenario of explosion at the model endpoint luminosity for a rotating star.

• OSTI ID: 21378076
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 706; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BINARY STARS
COLOR
ERUPTIVE VARIABLE STARS
EVOLUTION
EXPLOSIONS
GALAXIES
GIANT STARS
LUMINOSITY
MASS
OPTICAL PROPERTIES
ORGANOLEPTIC PROPERTIES
PHYSICAL PROPERTIES
STAR EVOLUTION
STARS
SUPERGIANT STARS
SUPERNOVAE
TELESCOPES
VARIABLE STARS