TY - JOUR
T1 - Coronal lines and dust formation in SN 2005ip
T2 - Not the brightest, but the hottest type IIn supernova
AU - Smith, Nathan
AU - Silverman, Jeffrey M.
AU - Chornock, Ryan
AU - Filippenko, Alexei V.
AU - Wang, Xiaofeng
AU - Li, Weidong
AU - Ganeshalingam, Mohan
AU - Foley, Ryan J.
AU - Rex, Jacob
AU - Steele, Thea N.
N1 - Funding Information:
We acknowledge interesting discussions concerning the nature of SN 2005ip with O. Fox and R. Chevalier. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration (NASA). The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. We wish to extend special thanks to those of Hawaiian ancestry on whose sacred mountain we are privileged to be guests. We are grateful to the staffs at the Lick and Keck Observatories for their dedicated services. Also, we acknowledge S. Park, D. Pooley, D. Poznanski, and D. S. Wong for assistance with some of the observations. KAIT was constructed and supported by donations from Sun Microsystems, Inc., the Hewlett-Packard Company, AutoScope Corporation, Lick Observatory, the US National Science Foundation (NSF), the University of California, the Sylvia & Jim Katzman Foundation, and the TABASGO Foundation. A.V.F.’s supernova group at U.C. Berkeley is supported by NSF grant AST–0607485 and by the TABASGO Foundation.
Funding Information:
We acknowledge interesting discussions concerning the nature of SN 2005ip with O. Fox and R. Chevalier. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration (NASA). The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. We wish to extend special thanks to those of Hawaiian ancestry on whose sacred mountain we are privileged to be guests. We are grateful to the staffs at the Lick and Keck Observatories for their dedicated services. Also, we acknowledge S. Park, D. Pooley, D. Poznanski, and D. S. Wong for assistance with some of the observations. KAITwas constructed and supported by donations from Sun Microsystems, Inc., the Hewlett-Packard Company, AutoScope Corporation, Lick Observatory, the US National Science Foundation (NSF), the University of California, the Sylvia & Jim Katzman Foundation, and the TABASGO Foundation. A.V.F.'s supernova group at U.C. Berkeley is supported by NSF grant AST-0607485 and by the TABASGO Foundation.
Publisher Copyright:
© 2009 The American Astronomical Society. All rights reserved. Printed in the U.S.A.
PY - 2009/4/20
Y1 - 2009/4/20
N2 - We present optical photometry and spectroscopy of SN 2005ip for the first 3 yr after discovery, showing an underlying Type II-L supernova (SN) interacting with a steady wind to yield an unusual Type IIn spectrum. For the first ∼160 days, it had a fast linear decline from a modest peak absolute magnitude of about -17.4 (unfiltered), followed by a plateau at roughly -14.8 for more than 2 yr. Initially having a normal broad-lined spectrum superposed with sparse narrow lines from the photoionized circumstellar medium (CSM), it quickly developed signs of strong CSM interaction with a spectrum similar to that of SN 1988Z. As the underlying SN II-L faded, SN 2005ip exhibited a rich high-ionization spectrum with a dense forest of narrow coronal lines, unprecedented among SNe but reminiscent of some active galactic nuclei. The line-profile evolution of SN 2005ip confirms that dust formation caused its recently reported infrared excess, but these lines reveal that it is the first SN to show clear evidence for dust in both the fast SN ejecta and the slower postshock gas. SN 2005ip's complex spectrum confirms the origin of the strange blue continuum in SN 2006jc, which also had postshock dust formation. We suggest that SN 2005ip's late-time plateau and coronal spectrum result from rejuvenated CSM interaction between a sustained fast shock and a clumpy stellar wind, where X-rays escape through the optically thin interclump regions to heat the preshock CSM to coronal temperatures.
AB - We present optical photometry and spectroscopy of SN 2005ip for the first 3 yr after discovery, showing an underlying Type II-L supernova (SN) interacting with a steady wind to yield an unusual Type IIn spectrum. For the first ∼160 days, it had a fast linear decline from a modest peak absolute magnitude of about -17.4 (unfiltered), followed by a plateau at roughly -14.8 for more than 2 yr. Initially having a normal broad-lined spectrum superposed with sparse narrow lines from the photoionized circumstellar medium (CSM), it quickly developed signs of strong CSM interaction with a spectrum similar to that of SN 1988Z. As the underlying SN II-L faded, SN 2005ip exhibited a rich high-ionization spectrum with a dense forest of narrow coronal lines, unprecedented among SNe but reminiscent of some active galactic nuclei. The line-profile evolution of SN 2005ip confirms that dust formation caused its recently reported infrared excess, but these lines reveal that it is the first SN to show clear evidence for dust in both the fast SN ejecta and the slower postshock gas. SN 2005ip's complex spectrum confirms the origin of the strange blue continuum in SN 2006jc, which also had postshock dust formation. We suggest that SN 2005ip's late-time plateau and coronal spectrum result from rejuvenated CSM interaction between a sustained fast shock and a clumpy stellar wind, where X-rays escape through the optically thin interclump regions to heat the preshock CSM to coronal temperatures.
KW - Circumstellar matter
KW - Stars: mass loss
KW - Stars: winds, outflows
KW - Supernovae: individual (SN 2005ip)
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U2 - 10.1088/0004-637X/695/2/1334
DO - 10.1088/0004-637X/695/2/1334
M3 - Article
AN - SCOPUS:85021118009
SN - 0004-637X
VL - 695
SP - 1334
EP - 1350
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 2
ER -