Volume 543, July 2012
|Number of page(s)||16|
|Section||Stellar structure and evolution|
|Published online||02 July 2012|
1 Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, 464-8602 Nagoya, Japan
2 Sendai Astronomical Observatory, Nishikigaoka, Aoba-ku, 989-3123 Sendai, Japan
3 Koyama Astronomical Observatory, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, 603-8555 Kyoto, Japan
4 Subaru Telescope, National Astronomical Observatory of Japan, 650 North A’ohoku Place, Hilo, HI 96720, USA
5 Nishi-Harima Astronomical Observatory, Sayo-cho, 679-5313 Hyogo, Japan
6 Hiroshima Astrophysical Science Center, Hiroshima University, Kagamiyama, Higashi-Hiroshima, 739-8526 Hiroshima, Japan
7 Fujii Bisei Obsevatory, Kurosaki, Tamashima, Kurashiki, 713-8126 Okayama, Japan
8 Astronomical Observatory of Padova, Asiago Section, Osservatorio Astrofisico, 36012 Asiago (Vi), Italy
9 Gunma Astronomical Observatory, Agatsuma-gun, 377-0702 Gunma, Japan
10 Graduate School of Sciences, Kyushu University, Hakozaki, Higashi-ku, 812-8581 Fukuoka, Japan
11 Astronomical Institute, Osaka Kyoiku University, Asahigaoka, Kashiwara, 582-8582 Osaka, Japan
Received: 21 October 2011
Accepted: 30 March 2012
We present optical (B, V, Rc, Ic and y) and near-infrared (J, H, and Ks) photometric and spectroscopic observations of a classical nova V1280 Scorpii for five years from 2007 to 2011. Our photometric observations show a declining event in optical bands shortly after the maximum light, which took about 250 days to recover. This event was most probably caused by dust formation. The event was accompanied by a short (~30 days) re-brightening episode (~2.5 mag in V), which suggests that there had been some re-ignition of the surface nuclear burning. After 2008, the y band observations show a very long plateau at around y = 10.5 for more than 1000 days until April 2011 (~1500 days after the maximum light). The nova had taken a very long time (~50 months) to enter the nebular phase, according to a clear detection of both [O iii] 4959 and 5007 and is still continuing to generate the wind caused by H-burning. This finding suggests that historically V1280 Sco is evolving at its slowest ever measured rate. The interval from the maximum light (2007 February 16) to the beginning of the nebular phase is longer than any previously known slow novae: V723 Cas (18 months), RR Pic (10 months), or HR Del (8 months). It suggests that the mass of a white dwarf in the V1280 Sco system might be 0.6 M⊙ or lower. The distance, based on our measurements of the expansion velocity combined with the directly measured size of the dust shell, is estimated to be 1.1 ± 0.5 kpc.
Key words: stars: individual: V1280 Sco / novae, cataclysmic variables / stars: abundances / stars: distances
© ESO, 2012
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.