THE PROGENITOR OF SUPERNOVA 2011dh/PTF11eon IN MESSIER 51

Journal Article · Thu Nov 10 00:00:00 EST 2011 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/741/2/L28· OSTI ID:22047379

Van Dyk, Schuyler D ^[1]; Li, Weidong; Cenko, S Bradley; Silverman, Jeffrey M; Filippenko, Alexei V ^[2]; Kasliwal, Mansi M; Horesh, Assaf; Ofek, Eran O; Quimby, Robert M; Kulkarni, Shrinivas R ^[3]; Kraus, Adam L ^[4]; Arcavi, Iair; Gal-Yam, Avishay; Yaron, Ofer; Polishook, David ^[5]

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1. Spitzer Science Center/Caltech, Pasadena CA 91125 (United States)
2. Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)
3. Astronomy Department, California Institute of Technology, Pasadena, CA 91125 (United States)
4. Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States)
5. Department of Particle Physics and Astrophysics, Weizmann Institute of Science, 76100 Rehovot (Israel)

We have identified a luminous star at the position of supernova (SN) 2011dh/PTF11eon, in pre-SN archival, multi-band images of the nearby, nearly face-on galaxy Messier 51 (M51) obtained by the Hubble Space Telescope with the Advanced Camera for Surveys. This identification has been confirmed, to the highest available astrometric precision, using a Keck-II adaptive-optics image. The available early-time spectra and photometry indicate that the SN is a stripped-envelope, core-collapse Type IIb, with a more compact progenitor (radius {approx} 10{sup 11} cm) than was the case for the well-studied SN IIb 1993J. We infer that the extinction to SN 2011dh and its progenitor arises from a low Galactic foreground contribution, and that the SN environment is of roughly solar metallicity. The detected object has absolute magnitude M{sup 0}{sub V} Almost-Equal-To -7.7 and effective temperature {approx}6000 K. The star's radius, {approx}10{sup 13} cm, is more extended than what has been inferred for the SN progenitor. We speculate that the detected star is either an unrelated star very near the position of the actual progenitor, or, more likely, the progenitor's companion in a mass-transfer binary system. The position of the detected star in a Hertzsprung-Russell diagram is consistent with an initial mass of 17-19 M{sub Sun }. The light of this star could easily conceal, even in the ultraviolet, the presence of a stripped, compact, very hot ({approx}10{sup 5} K), nitrogen-rich Wolf-Rayet star progenitor.

• OSTI ID: 22047379
• Journal Information: Astrophysical Journal Letters, Vol. 741, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ACCURACY
ASTRONOMY
ASTROPHYSICS
CAMERAS
GALAXIES
HERTZSPRUNG-RUSSELL DIAGRAM
MASS TRANSFER
NITROGEN
PHOTOMETRY
STAR EVOLUTION
SUPERNOVAE
TELESCOPES
ULTRAVIOLET RADIATION
VISIBLE RADIATION
WOLF-RAYET STARS