VV Pup: polar variations
Observed: 13 Jan, 2, 15, 20 Feb, 30 Nov 2007
29 Dec 2007
This cataclysmic polar was observed in low state at the beginning
of 2007. It was back to its usual level in November.
VV Pup is a cataclysmic system, that is a binary with an accreting white
dwarf. The white dwarf is strongly magnetized (about 10^8 gauss), its
spin is synchronized with the orbital motion, and the accretion is funneled
by the magnetic field (no accretion disk). This type of cataclysmic is
a polar or an AM Her. The orbital/spin period is 100.44 mn.
This is a follow up of my 2006 observations.
VV Pup was observed with a 203mm SC telescope and a SBIG ST7E camera (KAF401E CCD).
The comparison star is GSC6004-03141 with an assumed unfiltered magnitude of 13.0.
For the only one V observation, the comparison star is LONEOS VV Pup Meech G with V=13.76.
VV Pup could barely be detected with 200s exposures:
The phase is computed for a period of 0.069747d and 2,453,000.0 as the origin;
in 2006 the pulsation maximum was then near phase 0.5.
In November, VV Pup was bright enough to carry out time-series. 49 images were obtained.
The resulting light curve is:
Red: VV Pup, Blue: the check star shifted by +1.5mag.
The error bars are +/- the 1 sigma
The check star is UCAC2-24-322-717 at RA=08h15mn13.00s DEC=-19°02'14.7"
observed with an average magnitude of 15.119,
an average statistical uncertainty of 0.035mag
and a standard deviation of 0.046mag.
The resulting phase plot:
Telescope and camera configuration.
Computer and software configuration.