* Astronomy

Title: SN2010jp (PTF10aaxi): A Jet-Driven Type II Supernova
Authors: Nathan Smith, S. Bradley Cenko, Nat Butler, Joshua S. Bloom, Mansi M. Kasliwal, Assaf Horesh, Shrinivas R. Kulkarni, Nicholas M. Law, Peter E. Nugent, Eran O. Ofek, Dovi Poznanski, Robert M. Quimby, Branimir Sesar, Sagi Ben-Ami, Iair Arcavi, Avishay Gal-Yam, David Polishook, Dong Xu, Ofer Yaron, Dale A. Frail, Mark Sullivan

We present photometry and spectroscopy of the peculiar TypeII supernova (SN) 2010jp, also named PTF10aaxi. The light curve exhibits a linear decline with a relatively low peak absolute magnitude of only -15.9, and a low radioactive decay luminosity at late times that suggests a nickel mass below 0.003 solar masses. Spectra of SN2010jp display an unprecedented triple-peaked H \alpha line profile, showing: (1) a narrow (800 km/s) central component that suggests shock interaction with dense CSM; (2) high-velocity blue and red emission features centered at -12600 and +15400 km/s; and (3) broad wings extending from -22000 to +25000 km/s. These features persist during 100 days after explosion. We propose that this line profile indicates a bipolar jet-driven explosion, with the central component produced by normal SN ejecta and CSM interaction at mid latitudes, while the high-velocity bumps and broad line wings arise in a nonrelativistic bipolar jet. Two variations of the jet interpretation seem plausible: (1) A fast jet mixes 56Ni to high velocities in polar zones of the H-rich envelope, or (2) the reverse shock in the jet produces blue and red bumps in Balmer lines when a jet interacts with dense CSM. Jet-driven SNeII are predicted for collapsars resulting from a wide range of initial masses above 25 solar masses at sub-solar metallicity. This seems consistent with the SN host environment, which is either an extremely low-luminosity dwarf galaxy or very remote parts of an interacting pair of star-forming galaxies. It also seems consistent with the low 56Ni mass that may accompany black hole formation. We speculate that the jet survives to produce observable signatures because the star's H envelope was mostly stripped away by previous eruptive mass loss.

Read more (2164kb, PDF)