MAXI/GSC detection of X-ray brightening from the Be/X-ray binary pulsar GS1843-02 (4U 1850-02)
ATel #11033; M. Nakajima, H. Negoro (Nihon U.), T. Mihara, S. Nakahira (RIKEN), M. Serino (AGU), S. Ueno, H. Tomida, M. Ishikawa, Y. Sugawara, N. Isobe, R. Shimomukai (JAXA), M. Sugizaki, W. Iwakiri, M. Shidatsu, F. Yatabe, Y. Takao, M. Matsuoka (RIKEN), N. Kawai, S. Sugita, T. Yoshii, Y. Tachibana, S. Harita, Y. Muraki, K. Morita (Tokyo Tech), A. Yoshida, T. Sakamoto, Y. Kawakubo, Y. Kitaoka, T. Hashimoto (AGU), H. Tsunemi, T. Yoneyama (Osaka U.), T. Kawase, A. Sakamaki (Nihon U.), Y. Ueda, T. Hori, A. Tanimoto, S. Oda, T. Morita, S. Yamada (Kyoto U.), Y. Tsuboi, Y. Nakamura, R. Sasaki, H. Kawai (Chuo U.), M. Yamauchi, C. Hanyu, K, Hidaka (Miyazaki U.), T. Kawamuro (NAOJ), K. Yamaoka (Nagoya U.)
on 6 Dec 2017; 10:17 UT
Credential Certification: Motoki Nakajima (nakajima.motoki@nihon-u.ac.jp)
Subjects: X-ray, Binary, Neutron Star, Transient, Pulsar
The MAXI/GSC nova-alert system (Negoro et al. 2016) detected a weak X-ray brightening from a position consistent with the Be/X-ray binary pulsar GS1843-02 (4U 1850-02) on 2017 December 3.73 (MJD 58090.73). On 2017 December 4, the one-day averaged X-ray flux reached a value of 0.030 +/- 0.005 photons/s/cm2 (26 +/- 4 mCrab) in the 4-10 keV energy band. The orbital phase of the trigger date is ∼0.99 (Porb=242.18 d, T0=49616.48(MJD) ; Finger et al. 1999), which is consistent with the onsets of the previous outbursts (Atel#4350,#7386,#8392,#9339). In addition, the brightening profile matches with the previous outbursts. Therefore, the current event is considered as a normal (type-I) outburst. The current brightening is also detected by Swift/BAT. The 15-50 keV flux exhibited more rapid increase and it reached 0.019 +/- 0.005 counts/s/cm2 (88 +/- 21 mCrab) on 2017 December 5 (MJD 58092).
The latest source flux can be checked at the following pages;
MAXI(http://maxi.riken.jp/top/index.php?cid=1&jname=J1848-024),
Swift/BAT(http://swift.gsfc.nasa.gov/results/transients/weak/GS1843-02/),
Fermi/GBM(http://gammaray.msfc.nasa.gov/gbm/science/pulsars/lightcurves/2s1845.html), and
the BeXRB monitor page(http://integral.esac.esa.int/bexrbmonitor/webpage_oneplot.php).