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ID 34779
file
creator
Tanaka, Masaomi
Kawabata, Koji S.
Hattori, Takashi
Mazzali, Paolo A.
Aoki, Kentaro
Iye, Masanori
Maeda, Keiichi
Nomoto, Ken'ichi
Pian, Elena
Sasaki, Toshiyuki
subject
supernovae: general
supernovae: individual (SNe 2009jf, 2009mi)
techniques: polarimetric
NDC
Astronomy. Space sciences
abstract
We study the multi-dimensional geometry of supernova (SN) explosions by means of spectropolarimetric observations of stripped-envelope SNe, i.e., SNe without a hydrogen-rich layer. We perform spectropolarimetric observations of two stripped-envelope SNe, Type Ib SN 2009jf and Type Ic SN 2009mi. Both objects show non-zero polarization at the wavelength of the strong lines. They also show a loop in the Stokes Q-U diagram, which indicates a non-axisymmetric, three-dimensional ion distribution in the ejecta. We show that five out of six stripped-envelope SNe, which have been observed spectropolarimetrically so far, show such a loop. This implies that a three-dimensional geometry is common in stripped-envelope SNe. We find that stronger lines tend to show higher polarization. This effect is not related to the geometry, and must be corrected for to compare the polarization of different lines or different objects. Even after the correction, however, there remains a dispersion of polarization degree among different objects. Such a dispersion might be caused by three-dimensional clumpy ion distributions viewed from different directions.
journal title
Astrophysical Journal
volume
Volume 754
issue
Issue 1
start page
63
date of issued
2012
publisher
IOP Publishing Ltd
issn
0004-637X
ncid
publisher doi
language
eng
nii type
Journal Article
HU type
Journal Articles
DCMI type
text
format
application/pdf
text version
publisher
rights
(c) 2012. The American Astronomical Society. All rights reserved. Printed in the U.S.A.
relation url
department
Hiroshima Astrophysical Science Center