Comment to ATEL #4395: MAXI/GSC X-ray light curve of 4U 1630-472 updated with the latest calibration shows no drop in soft X-ray (2-4 keV) band on 2012 September 18
ATel #4406; M. Sugizaki (RIKEN), S. Ueno, H. Tomida, S. Nakahira, M. Ishikawa (JAXA), T. Mihara, M. Serino, T. Yamamoto, J. Sugimoto, M. Matsuoka (RIKEN), N. Kawai, M. Morii, R. Usui, K. Ishikawa (Tokyo Tech), A. Yoshida (AGU), H. Tsunemi, M. Kimura (Osaka U.), H. Negoro, M. Nakajima, M. Asada, H. Sakakibara, N. Serita (Nihon U.), Y. Ueda, K. Hiroi, M. Shidatsu, R. Sato (Kyoto U.), Y. Tsuboi, M. Higa (Chuo U.) M. Yamauchi, Y. Nishimura, T. Hanayama, K. Yoshidome (Miyazaki U.), K. Yamaoka (Waseda U.) report on behalf of the MAXI team:
on 21 Sep 2012; 09:30 UT
Credential Certification: Mutsumi Sugizaki (sugizaki@riken.jp)
Subjects: X-ray, Binary, Black Hole
We reprocessed the MAXI/GSC data using the latest calibration data,
then found that the sharp soft-X-ray drop in 2-4 keV band as seen in
the past archived files at http://maxi.riken.jp/top/index.php?cid=1&jname=J1634-473
and reported in ATEL #4395 was due to the calibration issue in the
quick-look analysis process.
The drop of the 2-4 keV band cannot be seen in the light curve
processed using the latest calibration files. The issue could appear in
QL light curves of several sources covered by the GSC-2 detector after
2012 April 17 on which the detector high voltage was changed. The QL
light curves were replaced one day later every day with the corrected
DL results. We fixed the calibration files in the QL process and
the archived data in the MAXI web site.
We also comment that the X-ray flux of 4U 1630-472 began to increase
on 2012 September 5 (MJD=56175) again and now at 0.8 Crab in 4-10 keV
band.
