Dear dwarf nova fans,
According to IBVS No. 4360, Antipin discovered another new dwarf nova (bright!) in the eta Her field.
Var43 16h 25m 01s.7 +39o 09' 26" (J2000.0) UG 12.5-17.5p
Antipin reports that the duration of the best-observed outburst is between 12 and 18 days.
Unfiltered time-series CCD photometry of Var43 Her (*) at the Center for Backyard Astrophysics Belgium (CBA Observatory), using a 25-cm f/6.3 SCT telescope and ST-7 CCD, on October 13/14, 1996 shows the existence of weak superhumps with a mean amplitude of approx. 0.14 mag. This establishes Var43 Her as a new member of the UGSU-type dwarf novae.
Determination of a superhump period value is extremely difficult due to the short observing window (photometry of Var43 Her in Belgium currently is restricted to approx. 1.5 hours). We therefore would like to request assistance from other observatories, so that multi-longitudinal coverage becomes possible.
The present outburst of Var43 Her was first announced by Ch. Scovil (VSNET message), and detected on Oct. 7, 1996. The object is now fading and any attempts to study the superhumps should be made in the next couple of nights.
(*) Var43 Her was discovered by Antipin (IBVS 4360) and is located at R.A. = 16h25m01s.7, Decl = +39d09'26" (J2000.0). Magnitude range is 12.5 - 17.5p.
The recently discovered SU UMa-type dwarf nova , V844 Her = Var43 Her is undergoing a superoutburst as indicatied by the following observations. (Most magnitudes based on Antipin's photographic sequence; the true V-magnitude may be brighter by ~0.5 to 1.0 mag.)
YYMMDD(UT) mag code 970519.964 <149 POY 970520.340 <153 MRV 970521.319 131 MRV 970522.367 132 MRV 970522.930 135 KNN 970523.137 131 MRV 970523.364 134 MRV
The object was last reported to be in outburst in 1996 Oct., when Tonny Vanmunster detected superhumps, finally enabling an unambiguous classification of this object (cf. vsnet-obs 4075, http://www.kusastro.kyoto-u.ac.jp/vsnet/Mail/vsnet-obs/msg04075.html).
Last night I obtained over 4 hours of CCD photometry of Var43 Her = V844 Her. The resulting light curve clearly showed prominent super- humps, hence qualifying the present outburst again as a superoutburst. So far the good news ...
But ... at the moment I launched the period determination programme, my hard disk crashed (hopefully without data loss). When I have my computer back in a few days, I hope to continue the period determination (without interrupts this time ?) and I will communicate the superhump period value.
(CVC 141, vsnet-alert 935)
V844 Her = Var43 Her [UGSU, 12.5p - 17.5p] ==========================================
Tonny Vanmunster, CBA Belgium reports : "We obtained 4.1 hours of unfiltered CCD photometry of V844 Her (Var43 Her) at CBA Belgium, on 997, May 23/24, using a 0.25-m SCT and ST-7 CCD. The light curve clearly shows the existence of prominent superhumps with a semi- amplitude of 0.18 mag. A preliminary period analysis, using the PDM method, yields the following best estimate of the superhump period : 0.056d +/- 0.001d. This is among the shortest superhump periods currently known !
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