MULTI-WAVELENGTH PROPERTIES OF THE TYPE IIb SN 2008ax

Journal Article · Tue Oct 20 00:00:00 EDT 2009 · Astrophysical Journal (Online)

DOI:https://doi.org/10.1088/0004-637X/704/2/L118· OSTI ID:21367332

Roming, P W. A.; Pritchard, T A; Brown, P J; Hoversten, E A ^[1]; Holland, S T ^[2]; Immler, S ^[3]; Stockdale, C J; Vandrevala, C ^[4]; Weiler, K W ^[5]; Panagia, N ^[6]; Van Dyk, S D ^[7]; Milne, P A ^[8]; Oates, S R ^[9]; Russell, B ^[10]

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1. Department of Astronomy and Astrophysics, Penn State University, 525 Davey Laboratory, University Park, PA 16802 (United States)
2. Universities Space Research Association, 10227 Wincopin Circle, Suite 500, Columbia, MD 21044 (United States)
3. NASA/Goddard Space Flight Center, Astrophysics Science Division, Code 662, Greenbelt, MD 20771 (United States)
4. Physics Department, Marquette University, P.O. Box 1881, Milwaukee, WI 53201-1881 (United States)
5. Naval Research Laboratory, Code 7210, Washington, DC 20375-5320 (United States)
6. Space Telescope Science Institute, 3700 San Martin Dr, Baltimore, MD 21218 (United States)
7. Spitzer Science Center, IPAC, California Institute of Technology, M/C 220-6, Pasadena, CA 91125 (United States)
8. Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States)
9. Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom)
10. Department of Physics, University of Maryland, College Park, MD 20742 (United States)

We present the UV, optical, X-ray, and radio properties of the Type IIb SN 2008ax discovered in NGC 4490. The observations in the UV are one of the earliest of a Type IIb supernova (SN). On approximately day 4 after the explosion, a dramatic upturn in the u and uvw1 (lambda{sub c} = 2600 A) light curves occurred after an initial rapid decline which is attributed to adiabatic cooling after the initial shock breakout. This rapid decline and upturn is reminiscent of the Type IIb SN 1993J on day 6 after the explosion. Optical/near-IR spectra taken around the peak reveal prominent Halpha, He I, and Ca II absorption lines. A fading X-ray source is also located at the position of SN 2008ax, implying an interaction of the SN shock with the surrounding circumstellar material and a mass-loss rate of the progenitor of M-dot=(9+-3)x10{sup -6}M{sub odot}yr{sup -1}. The unusual time evolution (14 days) of the 6 cm peak radio luminosity provides further evidence that the mass-loss rate is low. Combining the UV, optical, X-ray, and radio data with models of helium exploding stars implies the progenitor of SN 2008ax was an unmixed star in an interacting binary. Modeling of the SN light curve suggests a kinetic energy (E{sub k} ) of 0.5 x 10{sup 51} erg, an ejecta mass (M {sub ej}) of 2.9 M {sub sun}, and a nickel mass (M {sub Ni}) of 0.06 M {sub sun}.

• OSTI ID: 21367332
• Journal Information: Astrophysical Journal (Online), Vol. 704, Issue 2; Other Information: DOI: 10.1088/0004-637X/704/2/L118; ISSN 1538-4357
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ABSORPTION
EXPLOSIONS
HELIUM
INFRARED SPECTRA
KINETIC ENERGY
LUMINOSITY
NICKEL
SUPERNOVAE
ULTRAVIOLET RADIATION
VISIBLE RADIATION
X-RAY SOURCES
BINARY STARS
ELECTROMAGNETIC RADIATION
ELEMENTS
ENERGY
ERUPTIVE VARIABLE STARS
FLUIDS
GASES
METALS
NONMETALS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATION SOURCES
RADIATIONS
RARE GASES
SORPTION
SPECTRA
STARS
TRANSITION ELEMENTS
VARIABLE STARS