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ID 29240
file
creator
Kawabata, Koji S.
Kinugasa, Kenzo
Tanaka, Masaomi
Imada, Akira
Maeda, Keiichi
Nomoto, Ken'ichi
Arai, Akira
Chiyonobu, Shingo
Hashimoto, Osamu
Honda, Satoshi
Ikejiri, Yuki
Itoh, Ryosuke
Kamata, Yukiko
Kawai, Nobuyuki
Komatsu, Tomoyuki
Konishi, Kohki
Kuroda, Daisuke
Miyamoto, Hisashi
Miyazaki, Satoshi
Nagae, Osamu
Nakaya, Hidehiko
Ohsugi, Takashi
Omodaka, Toshihiro
Sakai, Nobuyuki
Sasada, Mahito
Suzuki, Mariko
Taguchi, Hikaru
Takahashi, Hidenori
Yamashita, Takuya
Yanagisawa, Kenshi
subject
supernovae
general
supernovae
individual (SN 2009dc, SNe 2003fg, 2006gz)
NDC
Astronomy. Space sciences
abstract
We present early phase observations in optical and near-infrared wavelengths for the extremely luminous Type Ia supernova (SN Ia) 2009dc. The decline rate of the light curve is Delta m(15)(B) = 0.65 +/- 0.03, which is one of the slowest among SNe Ia. The peak V-band absolute magnitude is estimated to be M-V = -19.90 +/- 0.15 mag if no host extinction is assumed. It reaches M-V = -20.19 +/- 0.19 mag if we assume the host extinction of A(V) = 0.29 mag. SN 2009dc belongs to the most luminous class of SNe Ia, like SNe 2003fg and 2006gz. Our JHK(s)-band photometry shows that this SN is also one of the most luminous SNe Ia in near-infrared wavelengths. We estimate the ejected Ni-56 mass of 1.2 +/- 0.3 M-circle dot for the no host extinction case (and of 1.6 +/- 0.4 M-circle dot for the host extinction of A(V) = 0.29 mag). The C II lambda 6580 absorption line remains visible until a week after the maximum brightness, in contrast to its early disappearance in SN 2006gz. The line velocity of Si II lambda 6355 is about 8000 km s(-1) around the maximum, being considerably slower than that of SN 2006gz. The velocity of the C II line is similar to or slightly less than that of the Si II line around the maximum. The presence of the carbon line suggests that the thick unburned C+O layer remains after the explosion. Spectropolarimetric observations by Tanaka et al. indicate that the explosion is nearly spherical. These observational facts suggest that SN 2009dc is a super-Chandrasekhar mass SN Ia.
journal title
Astrophysical Journal Letters
volume
Volume 707
issue
Issue 2
start page
118
end page
122
date of issued
2009-12-20
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
author
relation url
department
Graduate School of Science