(vsnet-alert 306, T. Kato)
CCD observation at Ouda Station seems to show the eclipsing dwarf nova S10932 in outburst at V~13.5 on Jan. 1.83 UT. Since we have no precise finding chart and lack of suitable GSC stars in the CCD field, independent confirmation is very strongly urged.
R.A. (2000.0) Decl. type range S10932 12 39 32.1 +21 08 06 UG:+E 13.4 18.5p
In IBVS No. 4182 (Wenzel and Schwartz), S10932 (=RX J1239.5+2108) has been announced to be a new eclipsing cataclysmic variable (likely a dwarf nova) below the period gap. Intensive monitor for outbursts would be interesting as the third member of eclipsing SU UMa (candidates) in the northern hemisphere (the other two are HT Cas and DV UMa).
Position and the elements are as follows: 12h 39m 32s.1 +21o 08' 06" (J2000.0) UG:+E 13.4-18.5p (from Richter 1994, poster presented at Padova CV Conference)
According to IBVS No. 4182, the mid-eclipse times are given as:
Min.(hel.) = JD 2449486.4821 + 0.08703 E
(vsnet-alert 307, T. Kato)
Preliminary analysis of CCD observations at Ouda Station confirms the outburst of S10932 accompanied by a deep eclipse. The object is ~2.1 mag brighter in V than GSC 15.2 (12h39m24s.02 +21o14'14".8 J2000.0) outside eclipses. An eclipse was fortunately caught centered at JD (geocentric) 2450084.34935, with a depth of ~1.3 mag and a duration of 12min. The profile of the eclipse is remarkably similar to those observed in HT Cas during the recent outburst, but with some hint of totality lasting 1-2 min.
outburst image (object at the right bottom)
Taichi Kato & Ouda team
(vsnet-alert 309, T. Kato)
V-band CCD observations at Ouda Station (Kyoto University) indicates that S10932 was fading rapidly on Jan. 2. An approximate magnitude outside eclipses was V=14.8 on Jan. 2.89, while the object was observed at around V=14.0 on Jan. 1.83-1.89 (magnitudes were calibrated using GO Com and AL Com secondary standards). This fact suggests that the present outburst of S10932 is a normal one, which is also supported by the lack of apparent superhumps.
S10932 east field
(vsnet-alert 310, Peter Kroll and Gerold A. Richter)
The current outburst of this star led us to (re)analyse CCD observations made at Sonneberg Observatory with a 60-cm-Cassegrain telescope from 1994-May-11 to 1996-Jan-04.
Eclipsing times published in "Wenzel, Richter, Luthardt, Schwartz: IBVS 4182" are now improved. We have listed all eclipsing times based on CCD measurements and in addition four minima from the Sonneberg Sky Patrol (SSP):
Instr. HJD 2400000+ E O-C (d) SSP 41798.443 -88329 +0.000261 SSP 45814.407 -42189 -0.000097 SSP 46910.398 -29597 -0.000064 SSP 47265.515 -25517 -0.000849 CCD 49484.39297 -24 +0.000238 CCD 49484.48022 -23 +0.000449 CCD 49486.48240 0 +0.000740 CCD 49488.39654 22 +0.000029 CCD 49488.48385 23 +0.000301 CCD 49511.46160 287 -0.000159 CCD 49748.46836 3010 +0.000295 CCD 49758.47767 3125 +0.000158 CCD 49771.44638 3274 +0.000106 CCD 49771.53334 3275 +0.000027 CCD 49787.37358 3457 -0.000772 CCD 49787.46124 3458 -0.000150 CCD 49787.54842 3459 -0.000009 CCD 49787.63531 3460 -0.000158 CCD 49788.41972: 3469 +0.000904: CCD 49788.50576 3470 -0.000094 CCD 49788.59273 3471 -0.000163 CCD 50087.57025 6906 -0.000484 CCD 50087.65795 6907 +0.000178
Using these minima times (except uncertain minimum 3469), which are distributed over more than 20 years, and the eclipsing times published in "vsnet-alert 308" and "309" by Taichi Kato & Ouda team we could derive the following ephemerides:
Min (HJD) = J.D. 2449486.48166 + 0.0870386727 * EOur observations of 96-Jan-04/05 (E 6906 and E 6907) show the ecplises with an amplitude of about 4.4 mag (R band)!
Peter Kroll and Gerold A. Richter 96-Jan-09
Sonneberg Observatory, Germany
(area immediately east and S10932 nearby)
The 1996 Jan. outburst (Japanese text)
The 1997 Apr. outburst
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