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« : 13 Сентябрь 2010, 12:12:00 »

    Koichi Nishiyama, Kurume, Japan; and Fujio Kabashima, Miyaki,
Japan, report their discovery of a possible nova (mag 12.4) on two
40-s unfiltered CCD frames (limiting magnitude 13.9) taken around
Sept. 11.485 UT using a 105-mm f/4 camera lens (+ SBIG STL6303E
camera).  Five 5-s unfiltered CCD images taken on Sept. 11.505 with
Meade 200R 0.40-m f/9.8 reflector (+ SBIG STL1001E camera) yield
the following precise position for the new variable:  R.A. =
18h47m38s.38, Decl. = -3o47'14".1 (equinox 2000.0).  Nothing is
visible at this location on two past survey frames taken on Sept.
9.528 (limiting mag 13.9) and 10.466 (limiting mag 14.0) or on the
Digitized Sky Survey (1987 July 31; limiting red mag 18.3).
    Hiroyuki Maehara, Kwasan Observatory, Kyoto University,
reports on follow-up multicolor photometry of this object; CCD
images obtained with a 0.25-m telescope at the Kwasan Observatory
around Sept. 11.59 UT yield position end figures 38s.38, 13".9
(UCAC2 catalogue for position reference stars) and the following
magnitudes:  Sept. 11.588, I_c = 10.45; 11.589, R_c = 13.43;
11.590, V = 16.0.  Maehara adds that there are no IRAS or AKARI
catalogued point sources within 1' of the object, though a 2MASS
point source (J = 14.8, H = 14.2, K = 12.6) exists about 1".6 east
of the object's position.  Maehara also forwards a report by Akira
Arai and Mizuki Isogai (Kyoto Sangyo University) of a low-
resolution spectrum obtained on Sept. 11.597 with the 1.3-m Araki
telescope (+ LOSA/F2 spectrograph; R about 500).  The spectrum
shows H_alpha and O I 777.4-nm emission lines; the FWHM of the
H_alpha emission is 1500 km/s.  These features suggest that this
object is a classical nova.
    M. Yamanaka, R. Itoh, and T. Komatsu, Hiroshima University,
report that they obtained a low-resolution optical spectrum (range
450-900 nm; R = 400) of the nova on Sept. 11.60 UT at the Higashi-
Hiroshima Observatory of Hiroshima University.  The spectrum shows
a highly reddened continuum and no strong emission line below 600
nm.  The H_alpha feature, whose emission line full-width-at-zero-
intensity (FWZI) is measured to be 3000 km/s, has a P-Cyg profile;
the H_alpha absorption component has FWZI = 1500 km/s.  An H_beta
feature is not detected in the spectrum.  O I 777.4-nm and O I
844.6-nm also exhibit P-Cyg line profiles, and their absorption
minima reach 1500 km/s.  The Ca II near-infrared triplet lines
849.8-, 854.2-, and 866.2-nm exhibit strong emission.  The
absorption of Ca II 866.2-nm has FWZI = 1500 km/s.  The Paschen
line series is also confirmed.  These characteristics suggest that
this nova is a "Fe II"-type nova.

                     (C) Copyright 2010 CBAT
2010 September 11              (9167)            Daniel W. E. Green

Sept 12.865 UT V = 16.43, Rc = 13.65

Mean transformed mags from 5x60s exposures in each of V and Rc using 0.35-m SCT
Comparison star mags derived from CMC-14 r' and 2MASS J & K

Mean position measured with Astrometrica and UCAC3:
RA 18h 47m 38.38s, Dec -3 47' 13.8" (J2000)

David Boyd