Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-06-10
Astronomy and Astrophysics
Astrophysics
9 pages, 8 figures, Accepted for publication in the Astrophysical Journal
Scientific paper
10.1086/592325
We present optical spectropolarimetric observations of Type Ic supernova (SN) 2007gr with Subaru telescope at 21 days after the maximum brightness (~37 days after the explosion). Non-zero polarization as high as ~3% is observed at the absorption feature of Ca II IR triplet. The polarization of the continuum light is ~0.5% if we estimate the interstellar polarization (ISP) component assuming that the continuum polarization has a single polarization angle. This suggests that the axis ratio of the SN photosphere projected to the sky is different from unity by ~10%. The polarization angle at the Ca II absorption is almost aligned to that of the continuum light. These features may be understood by the model where a bipolar explosion with an oblate photosphere is viewed from the slightly off-axis direction and explosively synthesized Ca near the polar region obscures the light originated around the minor axis of the SN photosphere. Given the uncertainty of the ISP, however, the polarization data could also be interpreted by the model with an almost spherically symmetric photosphere and a clumpy Ca II distribution.
Hattori Takashi
Kawabata Koji S.
Maeda Kei--ichi
Nomoto Ken'ichi
Tanaka Masaomi
No associations
LandOfFree
Optical Spectropolarimetry and Asphericity of Type Ic SN 2007gr does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Optical Spectropolarimetry and Asphericity of Type Ic SN 2007gr, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optical Spectropolarimetry and Asphericity of Type Ic SN 2007gr will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-174585