SN 1996ai in NGC 5005
SN 1996ai in NGC 5005 (vsnet-alert 448, Hitoshi Yamaoka)
Dear Colleagues,
Recent IAUC reports that the SN 1996ai in NGC 5005 is of type Ia. From its spectra, it is suggested to be around the maximum phase now and extremely obscurred, but the possibility that the SN 1996ai is the peculiar type Ia event has not been excluded. It may be cleared by R or I band photometry, in which it should be brighter than in the bluer bands. The I-band light curve differs between the 'standard' SN Ia and the peculiar one.
NGC 5005 has the distance module m-M = 31.64, from which the peek magnitude for 'standard' SN Ia is delived as nearly V = 12 mag. If the E(B-V) values announced in IAUCs (greater than or equal to 1.0) is correct, V magnitude will not exceed 15 mag, but the I magnitude should be 13 -- 14 at the maximum.
Its position is; R.A. = 13h10m58s.13, Decl. = +37o03'35".4 (equinox 2000.0) which is about 24" east and 4" north of the NGC 5005's center.
Photometric observations are enourmously encourged! If there are good sequence of reference stars, please announce it here. Prof. Skiff has been posted the V magnitudes for near field stars to 'vsnet-obs', which may help the comparison.
Refs: IAUC 6422, 6423.
Hitoshi Yamaoka, Kyushu Univ., Japan.
A few years ago I measured three stars near NGC 5005 in anticipation of it having a supernova. The Thompson & Bryan chart for this galaxy shows no photometry of decently faint stars near the galaxy. The two fainter ones here should be useful for V-band CCD photometry. The two fainter stars were the closest stars to the galaxy that I could measure with the Lowell 53cm telescope. These results (and those for several other galaxies) were published in the Webb Society Quarterly Journal.
Star name RA (2000) Dec V b-y n spec
HD 114428 13 10 03.0 +37 09 06 8.594 0.339 2 G5
.001 .005
GSC 2534-0604 13 11 15.1 +37 09 24 12.200 0.402 2
.034 .025
GSC 2534-0604 13 10 51.9 +37 08 08 13.257 0.448 2
.008 .023
HD 114428 has also been measured by Olsen (1993, A&AS 102,89) in the four-color system, and he gives V=8.613, b-y=0.334 from a single observation. For what it's worth, the galaxy is centered at 13 10 56 +37 03.6 (2000), and appears in the GSC as GSC 2534-0098, and also is IRAS 13086+3719.
\Brian Skiff (bas@lowell.edu)
...in Flagstaff, where the forests on the Peaks are burning... B-(
VSNET observations
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