We present results from a temporal analysis of the longest and the most sensitive X-ray observations of TV Columbae – a cataclysmic variable classified as an intermediate polar .
The observations were carried out with the RossiX - RayTimingExplorer ( RXTE ) Proportional Counter Array , ROSAT Position Sensitive Proportional Counter , and ASCA .
Data were analyzed using a one-dimensional CLEAN and Bayesian algorithms .
The presence of a nearly sinusoidal modulation due to the spin of the white dwarf is seen clearly in all the data , confirming the previous reports based on the EXOSAT data .
An improved period of 1909.7 \pm 2.5 s is derived for the spin from the RXTE data .
The binary period of 5.5hr is detected unambiguously in X-rays for the first time .
Several side-bands due to the interaction of these periods are observed in the power spectra , thereby suggesting contributions from both the disk-fed and the stream-fed accretion for TV Col .
The accretion disk could perhaps be precessing as side-bands due to the influence of 4 day period on the orbital period are seen .
The presence of a significant power at certain side-bands of the spin frequency indicates that the emission poles are asymmetrically located .
The strong power at the orbital side-bands seen in both the RXTE and ROSAT data gives an indication for an absorption site fixed in the orbital frame .
Both the spin and the binary modulation are found to be energy- dependent .
The fact that the spin modulation amplitude in TV Col decreases with energy is confirmed .
Hardness ratio variations and the energy dependent modulation depth during the spin modulation can be explained by partially covered absorbers in the path of X-ray emission region in the accretion stream .
Increased hardness ratio during a broad dip in the intensity at binary phase of 0.75–1.0 confirms the presence of a strong attenuation due to additional absorbers probably from an impact site of the accretion stream with the disk or magnetosphere .