2006CBET..666....2Y

As a potentially significant aside, Itagaki had reported (via H. Yamaoka, Kyushu University, on 2004 Oct. 20) a possible supernova close to the above position, and near the limit of his CCD frames, having position end figures 20s.81, 32".3. The following approximate magnitudes were then provided by Itagaki for that object, all 2004 dates: Oct. 1, [19.0; Sept. 18, [19.0; Oct. 15.816, 19.0 (near limit); 17.820, 19.0 (discovery). Now, Nakano reports the following apparently revised magnitudes from Itagaki from his 2004 frames: Oct. 14.816, 17.9; 15.806, 18.2; 16.819, 18.2; 21.794, 18.4; 23.772, 18.5; 23.775, 18.7; Nov. 7.713, [19.5; 9.757, [19.0; 22.675, [19.0. The average position end figures for the object from these same 2004 frames from Itagaki are 20s.82 ± 0s.02, 32".6 ± 0.4. In 2004, Yamaoka reported that he had examined Itagaki's images and the DSS images: The DSS blue images taken on 1953 Apr. 15, 1990 Jan. 29, and 1995 Nov. 23 show a starlike object of mag about 20 near (within 2" of) the reported position, noting that this had also been noticed by Itagaki, who therefore assumed that the "new" object was a pre-existing one; but the DSS red images from 1990 Jan. 24 and 1989 Dec. 8, and the DSS infrared image from 1998 Dec. 30, do not show this object, and Yamaoka surmised that the blue DSS object could be a blue cluster region that is extinguished by the light from the disk of UGC 4904 in the DSS red and infrared images. Yamaoka further surmised that the 2004 object might be a luminous blue variable, such as 2000ch (cf. IAUC 7415, 7417, 7419, 7421), or a reddened object behind the presumed blue cluster. Yamaoka concluded that the possibility of the variable object being a Galactic cataclysmic variable could not be excluded, but additional observations to clarify the puzzle in 2004 were not reported prior to the object's fading, despite requests from the Central Bureau.