MAXI/GSC detection of a new X-ray transient MAXI J1305-704

ATel #4024; R. Sato (Kyoto U.), M. Serino (RIKEN), S. Nakahira (JAXA), S. Ueno, H. Tomida, M. Ishikawa (JAXA), T. Mihara, M. Sugizaki, T. Yamamoto, M. Matsuoka (RIKEN), N. Kawai, M. Morii, R. Usui (Tokyo Tech), A. Yoshida (AGU), H. Tsunemi, M. Kimura (Osaka U.), H. Negoro, M. Nakajima, M. Asada, H. Sakakibara (Nihon U.), Y. Ueda, K. Hiroi, M. Shidatsu (Kyoto U.), Y. Tsuboi (Chuo U.) M. Yamauchi, Y. Nishimura, T. Hanayama (Miyazaki U.), K. Yamaoka (Waseda U.) report on behalf of the MAXI team:
on 10 Apr 2012; 07:42 UT
Credential Certification: Motoko Suzuki (motoko@crab.riken.jp)

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At 2012/04/09 11:24:23 UT (MJD=56026.47527), the MAXI/GSC alert system triggered a new X-ray transient at the position:
(R.A., Dec) = (196.416 deg, -70.415 deg) = (13 05 39.9, -70 24 54) (J2000),
which has a statistical uncertainty of 0.17 deg at the 90% confidence limit and an additional systematic uncertainty of 0.1 deg (90% containment radius).

The observed X-ray flux averaged over sixteen scan transits from 2012-04-09 5:10 to 2012-04-10 04:25 is 30+-18 mCrab in 4-10 keV band. No significant X-ray flux from the source had not been detected until these scan period.

The source locates at the 1.3-deg south-east from a bright low-mass X-ray binary 4U 1254-690. There is no known bright X-ray source within the error circle. We tentatively refer this transient as MAXI J1305-704. Follow-up observations are strongly encouraged.