TY - JOUR
T1 - Extraordinary luminous soft x-ray transient MAXI J0158-744 as an ignition of a nova on a very massive o-Ne white dwarf
AU - Morii, M.
AU - Tomida, H.
AU - Kimura, M.
AU - Suwa, F.
AU - Negoro, H.
AU - Serino, M.
AU - Kennea, J. A.
AU - Page, K. L.
AU - Curran, P. A.
AU - Walter, F. M.
AU - Kuin, N. P.M.
AU - Pritchard, T.
AU - Nakahira, S.
AU - Hiroi, K.
AU - Usui, R.
AU - Kawai, N.
AU - Osborne, J. P.
AU - Mihara, T.
AU - Sugizaki, M.
AU - Gehrels, N.
AU - Kohama, M.
AU - Kotani, T.
AU - Matsuoka, M.
AU - Nakajima, M.
AU - Roming, P. W.A.
AU - Sakamoto, T.
AU - Sugimori, K.
AU - Tsuboi, Y.
AU - Tsunemi, H.
AU - Ueda, Y.
AU - Ueno, S.
AU - Yoshida, A.
PY - 2013/12/20
Y1 - 2013/12/20
N2 - We present the observation of an extraordinary luminous soft X-ray transient, MAXI J0158-744, by the Monitor of All-sky X-ray Image (MAXI) on 2011 November 11. This transient is characterized by a soft X-ray spectrum, a short duration (1.3 × 103 s < ΔTd < 1.10 × 10 4 s), a rapid rise (<5.5 × 103 s), and a huge peak luminosity of 2 × 1040 erg s-1 in 0.7-7.0 keV band. With Swift observations and optical spectroscopy from the Small and Moderate Aperture Research Telescope System, we confirmed that the transient is a nova explosion, on a white dwarf in a binary with a Be star, located near the Small Magellanic Cloud. An early turn-on of the super-soft X-ray source (SSS) phase (<0.44 days), the short SSS phase duration of about one month, and a 0.92 keV neon emission line found in the third MAXI scan, 1296 s after the first detection, suggest that the explosion involves a small amount of ejecta and is produced on an unusually massive O-Ne white dwarf close to, or possibly over, the Chandrasekhar limit. We propose that the huge luminosity detected with MAXI was due to the fireball phase, a direct manifestation of the ignition of the thermonuclear runaway process in a nova explosion.
AB - We present the observation of an extraordinary luminous soft X-ray transient, MAXI J0158-744, by the Monitor of All-sky X-ray Image (MAXI) on 2011 November 11. This transient is characterized by a soft X-ray spectrum, a short duration (1.3 × 103 s < ΔTd < 1.10 × 10 4 s), a rapid rise (<5.5 × 103 s), and a huge peak luminosity of 2 × 1040 erg s-1 in 0.7-7.0 keV band. With Swift observations and optical spectroscopy from the Small and Moderate Aperture Research Telescope System, we confirmed that the transient is a nova explosion, on a white dwarf in a binary with a Be star, located near the Small Magellanic Cloud. An early turn-on of the super-soft X-ray source (SSS) phase (<0.44 days), the short SSS phase duration of about one month, and a 0.92 keV neon emission line found in the third MAXI scan, 1296 s after the first detection, suggest that the explosion involves a small amount of ejecta and is produced on an unusually massive O-Ne white dwarf close to, or possibly over, the Chandrasekhar limit. We propose that the huge luminosity detected with MAXI was due to the fireball phase, a direct manifestation of the ignition of the thermonuclear runaway process in a nova explosion.
UR - https://www.scopus.com/pages/publications/84890050555
UR - https://www.scopus.com/pages/publications/84890050555#tab=citedBy
U2 - 10.1088/0004-637X/779/2/118
DO - 10.1088/0004-637X/779/2/118
M3 - Article
AN - SCOPUS:84890050555
SN - 0004-637X
VL - 779
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 2
M1 - 118
ER -