[Aavso-photometry] Var Her 04 refined period based on >2500 CBA observations - new run started at CBA Belgium Observatory

[Tonny Vanmunster]

Dear colleagues,

I have been analysing 2582 CCD observations of Var Her 04, obtained between
JD +3181.0 and JD +3185.0 by following CBA observers : Lew Cook, Russ
Durkee, Donn Starkey, Dave Messier, Brian Martin, Tonny Vanmunster and
Michael Richmond. The impressive overall light curve is visible on
www.cbabelgium.com. Using the ANOVA period analysis method (in Peranso), I
obtain a superhump period value of 0.057717 +/- 0.000060 d. The ANOVA period
window is extremely 'clean' and is also shown on the afore mentioned
website. Other period analysis methods, such as PDM and Lomb-Scargle, all
consistently yield a similar signal, so we may assume that this is a very
accurate value.

Folding all available observations on the 0.057717 d period clearly points
to a superhump profile, but with irregular features superimposed. The
average amplitude in the phase window is about 0.2 mag.

I furthermore included a light curve obtained on June 27/28, 2004 at CBA
Belgium Observatory, on my website. It shows a number of intriguing, but
hard to explain modulations, that arise over various parts of the superhump
profile. In some cases, Var Her 04 drops by almost 0.15 mag in a couple of
minutes. This might again be eclipses, reappearing in the light curve.
Michael Richmond's observations, obtained on the same night, confirm the
irregular modulations.

Var Her 04 seems to be on its way to become one of the most interesting
newly discovered UGSU-type dwarf novae (likely even UGWZ) of the past years.
Keep on observing !

Best regards,
Tonny Vanmunster

PS : clear again over CBA Belgium Observatory tonight, so I'm hoping to see
continuation of the observations in the US.


Tonny Vanmunster
CBA Belgium Observatory
http://www.cbabelgium.com
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PERANSO : The Final Frontier of Period Analysis Software
http://www.peranso.com
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