IAU Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 8928: V2468 Cyg = N Cyg 2008; (3749)

The following International Astronomical Union Circular may be linked-to from your own Web pages, but must not otherwise be redistributed (see these notes on the conditions under which circulars are made available on our WWW site).

Read IAUC 8927  SEARCH Read IAUC 8929

View IAUC 8928 in .dvi, .ps or .PDF format.
IAUC number

                                                  Circular No. 8928
Central Bureau for Astronomical Telegrams
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
URL http://www.cfa.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)

     N. N. Samus, Institute of Astronomy, Russian Academy of
Sciences, informs us that this nova (cf. IAUC 8927) has been
assigned the variable-star designation V2468 Cyg.
     M. M. Beaky, Truman State University, reports that a CCD
spectrum (range 450-850 nm, resolution 0.4 nm/pixel) of V2468 Cyg,
acquired with the 0.36-m telescope at the Truman Observatory on
Mar. 11.46 UT, shows H_alpha (FWHM = 790 km/s) and H_beta lines to
be prominent in emission, and numerous Fe II emission lines are
also visible.  Thus, the nova belongs to the 'Fe II' class of
Williams (1992, A.J. 104, 725).
     CCD photometry of V2468 Cyg by K. Hornoch, Ondrejov, Czech
Republic, with a 0.65-m reflector:  Mar. 10.175 UT, V = 8.27 +/-
0.01, B-V = +1.10 +/- 0.03, V-I = +1.52 +/- 0.02 (comparison star
HIP 98323).  Visual magnitude estimates, in part from E. O. Waagen,
AAVSO:  Mar. 9.417, 7.7 (J. E. Bortle, Stormville, NY, U.S.A.);
10.187, 8.3 (Hornoch); 12.362, 8.1 (M. Bradbury, Greenwood, IN,
U.S.A.); 13.452, 9.2 (L. Shotter, Uniontown, PA, U.S.A.); 15.020,
9.0 (B. Granslo, Fjellhamar, Norway); 17.443, 8.6 (Shotter); 19.056,
9.6 (Granslo).

(3749) BALAM
     F. Marchis, Carl Sagan Center (CSC), SETI Institute; J.
Pollock, Appalachian State University (ASU); P. Pravec, Ondrejov
Observatory; M. Baek, CSC; J. Greene and L. Hutton, ASU; P.
Descamps, Institut de Mecanique Celeste et de Calcul des
Ephemerides; and D. E. Reichart, K. M. Ivarsen, J. A. Crain, M. C.
Nysewander, A. P. Lacluyze, J. B. Haislip, and J. S. Harvey,
University of North Carolina at Chapel Hill, report that
photometric observations obtained during 2007 July 15 to Oct. 19
reveal that the central object of (3749) is actually a binary
system with a mutual orbital period of 33.38 +/- 0.02 hr.  The
primary shows a rotation period of 2.80483 +/- 0.00002 hr and a
lightcurve amplitude of 0.13 mag.  Mutual eclipse/occultation
events that were 0.15 and 0.43-mag deep on July 18 and Sept. 8,
respectively, indicate a size ratio of the two inner components of
0.4 +/- 0.1.  The system's parameters need to be refined with
further observations.  A distant satellite of (3749) was discovered
in 2002 (see IAUC 7827) at a distance of 0".47 using adaptive
optics (AO) imaging capabilities.  A separation between the two
inner components showing mutual events is estimated to be roughly
20 km, corresponding to an angular separation of about 0".02, not
yet attainable with current AO systems.

                      (C) Copyright 2008 CBAT
2008 March 19                  (8928)            Daniel W. E. Green

Read IAUC 8927  SEARCH Read IAUC 8929

View IAUC 8928 in .dvi, .ps or .PDF format.

Our Web policy. Index to the CBAT/MPC/ICQ pages.

Valid HTML 4.01!