Spectropolarimetry of the Type IIb Supernova 2001ig

Abstract

We present spectropolarimetric observations of the Type IIb SN 2001ig in NGC 7424; conducted with the ESO VLT FORS1 on 2001 Dec 16, 2002 Jan 3 and 2002 Aug 16 or 13, 31 and 256 days post-explosion. These observations are at three different stages of the SN evolution: (1) The hydrogen-rich photospheric phase, (2) the Type II to Type Ib transitional phase and (3) the nebular phase. At each of these stages, the observations show remarkably different polarization properties as a function of wavelength. We show that the degree of interstellar polarization is 0.17%. The low intrinsic polarization (~0.2%) at the first epoch is consistent with an almost spherical (<10% deviation from spherical symmetry) hydrogen dominated ejecta. Similar to SN 1987A and to Type IIP SNe, a sharp increase in the degree of the polarization (~1%) is observed when the outer hydrogen layer becomes optically thin by day 31; only at this epoch is the polarization well described by a ``dominant axis.'' The polarization angle of the data shows a rotation through ~40 degrees between the first and second epochs, indicating that the asymmetries of the first epoch were not directly coupled with those observed at the second epoch. For the most polarized lines, we observe wavelength-dependent loop structures in addition to the dominant axis on the Q-U plane. We show that the polarization properties of Type IIb SNe are roughly similar to one another, but with significant differences arising due to line blending effects especially with the high velocities observed for SN 2001ig. This suggests that the geometry of SN 2001ig is related to SN 1993J and that these events may have arisen from a similar binary progenitor system.

arXiv comment42 pages, 12 figures (figs. 11 and 12 are both composed of four subpanels, figs. 6,7,8,11 and 12 are in color, fig. 1 is low res and a high res version is available at http://www.as.utexas.edu/~jrm/), ApJ Accepted

References in corpus (29)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• The Supernova -- Gamma-Ray Burst Connection
• The 1000 Brightest HIPASS Galaxies: HI Properties
• The massive binary companion star to the progenitor of supernova 1993J
• Detailed Analysis of Early to Late-Time Spectra of Supernova 1993J
• Pulsar spins from an instability in the accretion shock of supernovae
• Spectropolarimetry of SN 2001el in NGC 1448: Asphericity of a Normal Type Ia Supernova
• An Asymmetric, Energetic Type Ic Supernova Viewed Off-Axis, and a Link to Gamma-Ray Bursts
• A non-spherical core in the explosion of supernova SN 2004dj
• The Axially Symmetric Ejecta of Supernova 1987A
• Evidence for Asphericity in a Subluminous Type Ia Supernova: Spectropolarimetry of SN 1999by
• Analysis of the Flux and Polarization Spectra of the Type Ia Supernova SN 2001el: Exploring the Geometry of the High-velocity Ejecta
• Luminous Blue Variables as the progenitors of supernovae with quasi-periodic radio modulations
• The Radio and X-ray Luminous SN 2003bg and the Circumstellar Density Variations Around Radio Supernovae
• Is it Round? Spectropolarimetry of the Type II-P Supernova 1999em
• Optical Spectroscopy of Supernova 1993J During Its First 2500 Days
• Polarimetry of the Type Ia Supernova SN 1996X
• Modulations in the radio light curve of the Type IIb Supernova 2001ig: Evidence for a Wolf-Rayet binary progenitor?
• Spectropolarimetry of the Type Ic SN 2002ap in M74: More Evidence for Asymmetric Core Collapse
• Spectropolarimetry of the Type Ib/c SN 2005bf
• Pre-Maximum Spectropolarimetry of the Type Ia SN 2004dt
• Photospheric-Phase Spectropolarimetry and Nebular-Phase Spectroscopy of the Peculiar Type Ic Supernova 2002ap
• A postmortem investigation of the Type IIb supernova 2001ig
• Probing the Geometry and Circumstellar Environment of SN 1993J in M81
• Wolf-Rayet and O Star Runaway Populations from Supernovae
• Evidence for Extremely High Dust Polarization Efficiency in NGC 3184
• Polarization of SN 1987A Revisited
• Interstellar Polarization in M31
• De-leptonization and Non-Axisymmetric Instabilities in Core Collapse Supernovae

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