/GSC detection of an new intermediate duration burst from IGR J17062-6143
ATel #13827; H. Nishida, M. Serino (AGU), W. Iwakiri (Chuo U.), H. Negoro, M. Nakajima, M. Aoki, K. Kobayashi, R. Takagi, K, Asakura, K, Seino, S. Mokumoto (Nihon U.), T. Mihara, C. Guo, Y. Zhou, T. Tamagawa, M. Matsuoka (RIKEN), T. Sakamoto, S. Sugita, A. Yoshida (AGU), Y. Tsuboi, R. Sasaki, H. Kawai, Y. Okamoto, S. Kitakoga (Chuo U.), M. Shidatsu (Ehime U.), N. Kawai, R. Adachi, M. Niwano (Tokyo Tech), S. Nakahira, Y. Sugawara, S. Ueno, H. Tomida, M. Ishikawa, M. Tominaga, T. Nagatsuka (JAXA), Y. Ueda, S. Yamada, S. Ogawa, K. Setoguchi, T. Yoshitake (Kyoto U.), H. Tsunemi (Osaka U.), M. Yamauchi, K. Kurogi, K. Miike (Miyazaki U.), T. Kawamuro (NAOJ), K. Yamaoka (Nagoya U.), Y. Kawakubo (LSU), M. Sugizaki (NAOC)
on 23 Jun 2020; 09:57 UT
Credential Certification: Motoko Suzuki (motoko@crab.riken.jp)
Subjects: X-ray, Neutron Star
At 08:15:24 UT on 2020 June 22, the MAXI/GSC nova alert system triggered a
bright X-ray burst from the position consistent with that of the low-mass X-ray
binary IGR J17062-6143/Swift J1706.6-6146 (Churazov et al. A&A 467, 529,
2007). Previously, two intermediate-duration burst defined
in Cumming et al. (2006) and Falanga et al. (2008) were reported from this source
in 2012 (Barthelmy et al. 2012, Degenaar et al. 2013) and 2015 (Negoro et al.
2015, Keek et al. 2017).
The 4-10 keV X-ray flux averaged over the scan transit assuming a constant flux
was 2014 +- 73 mCrab (4-10keV, 1 sigma error). No interstellar absorption is
necessary for a blackbody fit to a GSC spectrum above 2 keV obtained in the scan
transit at 08:15. The blackbody model fit to the spectrum in the 2-20 keV band
gives the blackbody temperature of 2.32 +0.15 -0.14 keV. Assuming source
distance of 7.3 kpc (Keek et al. 2017), the source radius was 8.9 +1.0 -0.9
km or the bolometric source luminosity was 3.0 +- 0.4 × 1038
erg/s, which was 79% of empirical Eddington limit for a He type-I X-ray burst (3.8
× 1038 erg/s; Kuulkers et al. 2003).
There was no significant excess flux in the previous transit at 06:42 UT with an
upper limit of 20 mCrab. This time, no burst like profile could be seen during the
scan transit at 08:15, suggesting that the burst started before the scan transit.
Since the source has been marginally detected in the following scan transit at
09:48, we suggest that this is the third intermediate-duration burst from IGR J17062-6143/Swift
J1706.6-6146.
Barthelmy et al. 2012, GCN 13386
Churazov et al. 2007, A&A 467, 529
Cumming et al. 2006, ApJ 646, 429
Degenaar et al. 2013, ApJ 767, L37
Falanga et al. 2008, A&A 48, 43
Keek et al. 2017, ApJ, 836, 111
Kuulkers et al. 2003, A&A, 399, 663
Negoro et al. 2015, ATel 8241