Details

Autor(en) / Beteiligte

• Yamanaka, M
• Kawabata, K. S
• Kinugasa, K
• Tanaka, M
• Imada, A
• Maeda, K
• Nomoto, K
• Arai, A
• Chiyonobu, S
• Fukazawa, Y
• Hashimoto, O
• Honda, S
• Ikejiri, Y
• Itoh, R
• Kamata, Y
• Kawai, N
• Komatsu, T
• Konishi, K
• Kuroda, D
• Miyamoto, H
• Miyazaki, S
• Nagae, O
• Nakaya, H
• Ohsugi, T
• Omodaka, T
• Sakai, N
• Sasada, M
• Suzuki, M
• Taguchi, H
• Takahashi, H
• Tanaka, H
• Uemura, M
• Yamashita, T
• Yanagisawa, K
• Yoshida, M

Titel

Early Phase Observations of Extremely Luminous Type Ia Supernova 2009dc

Ist Teil von

• The Astrophysical journal, 2009-12, Vol.707 (2), p.L118-L122

Ort / Verlag

United States: IOP Publishing

Erscheinungsjahr

2009

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• 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 DELTAm{sub 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{sub V} = -19.90 +- 0.15 mag if no host extinction is assumed. It reaches M{sub V} = -20.19 +- 0.19 mag if we assume the host extinction of A{sub V} = 0.29 mag. SN 2009dc belongs to the most luminous class of SNe Ia, like SNe 2003fg and 2006gz. Our JHK{sub s} -band photometry shows that this SN is also one of the most luminous SNe Ia in near-infrared wavelengths. We estimate the ejected {sup 56}Ni mass of 1.2 +- 0.3 M{sub sun} for the no host extinction case (and of 1.6 +- 0.4 M{sub sun} for the host extinction of A{sub V} = 0.29 mag). The C II lambda6580 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 lambda6355 is about 8000 km s{sup -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.