Simultaneous Optical/X-ray data were acquired using the CTIO 1-m telescope with a GaAs phototube and the PCA on the XTE On April 13 and 14, 1996. At this time VV Puppis appeared to be roughly 1 magnitude fainter than normal. Below, we present light curves and power spectral densities of the data. The light curves are usually binned in 1.28 s intervals and have not been sky-subtracted or corrected for extinction. The power spectral densities are the excess power above Poisson noise. The r.m.s pulsed power is the square root of the plotted quantity.

The curves are for April 11, 13, and 14, 1996 from bottom-to-top

WL Light Curves
WL PSD


For any individual night, there is no clear-cut detection of a QPO. However, if we sum the data for all three nights a low significance result appears. The QPO is between 0.5 and 1 Hz with an amplitude of ~ (0.5 +- 0.2) % r.m.s. of the total signal (i.e., source+sky). Correcting for this effect implies a pulsed amplitude of ~ (1.5 +- 0.6) %.
Summed WL PSD

A year before our XTE/CTIO experiment (Feb 1995), we acquired VBR data for VV Puppis. There is a weak detection of a 0.7 Hz QPO in R with little or no QPO activity in B and V. To check out the marginal detection, see:

R-band Light Curves
R-band PSD
B-band Light Curves
B-band PSD
V-band Light Curves
V-band PSD