IM Peg: Swift confirmation of X-ray flare and erratum to ATel #6322 and #6296

ATel #6339; A. Kawagoe, Y. Tsuboi (Chuo U.), S. Nakahira, S. Ueno, H. Tomida, M. Kimura, Y. E. Nakagawa (JAXA), T. Mihara, M. Sugizaki, M. Morii, M. Serino , J. Sugimoto, T. Takagi, A. Yoshikawa, M. Matsuoka (RIKEN), N. Kawai, R. Usui, T. Yoshii, Y. Tachibana (Tokyo Tech), A. Yoshida, T. Sakamoto, Y. Nakano, Y. Kawakubo, H. Ohtsuki (AGU), H. Tsunemi, M. Sasaki (Osaka U.), , H. Negoro, M. Nakajima, K. Fukushima, T. Onodera, K. Suzuki (Nihon U.), Y. Ueda, M. Shidatsu, T. Kawamuro, T. Hori (Kyoto U.), M. Yamauchi, Y. Morooka (Miyazaki U.), K. Yamaoka (Nagoya U.) report on behalf of the MAXI team:
on 24 Jul 2014; 08:07 UT
Credential Certification: Yohko Tsuboi (tsuboi@phys.chuo-u.ac.jp)

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In ATel #6322 and #6296, we incorrectly stated the distance to IM Peg. According to Ratner et al. 2012 ApJS 201, 5, the distance to IM Peg is 96.4 ⁺_-0.7 pc not 9.6 pc, so the X-ray luminosities are actually 2 orders of magnitude higher than those quoted.
The correct luminosity in 4-10 keV band for ATel #6322 is 1× 10 ³³ ergs/s and that for ATel #6322 is 8× 10 ³² ergs/s with the assumed distance of 96.4 pc.

Also, a follow-up observation with the Swift XRT was executed at 00:04:17 UT on July 19 2014 and confirmed the identification. The observation refined the X-ray enhanced position as

RA(J2000) = 22h 53m 02.23s
Dec(J200) = -16d 50m 28.8s

with error radius of 2.1 arcsec (90% confidence), consistent with IM Peg. The flux in 0.3-10 keV band, obtained with the Swift XRT, is 8-9 mCrab, which corresponds to an absorbed luminosity of 2× 10 ³² ergs/s with assumed distance of 96.4 pc. This is one fourth of the flux obtained with the data from 06:56:57 UT to 14:41:31 UT on July 16th (#6296), and the decay of the flux can be seen also with the MAXI/GSC light curve (http://maxi.riken.jp/top/index.php?cid=1&jname=J2253+168).

We thank the Swift team for performing the observation.