Fast optical variability of SS 433

Abstract

We study the optical variability of the peculiar Galactic source SS 433 using the observations made with the Russian Turkish 1.5-m telescope (RTT150). A simple technique which allows to obtain high-quality photometric measurements with 0.3-1 s time resolution using ordinary CCD is described in detail. Using the test observations of nonvariable stars, we show that the atmospheric turbulence introduces no significant distortions into the measured light curves. Therefore, the data obtained in this way are well suited for studying the aperiodic variability of various objects. The large amount of SS 433 optical light curve measurements obtained in this way allowed us to obtain the power spectra of its flux variability with a record sensitivity up to frequencies of ~0.5 Hz and to detect its break at frequency =~2.4e-3 Hz. We suggest that this break in the power spectrum results from the smoothing of the optical flux variability due to a finite size of the emitting region. Based on our measurement of the break frequency in the power spectrum, we estimated the size of the accretion-disk photosphere as 2e12 cm. We show that the amplitude of the variability in SS 433 decreases sharply during accretion-disk eclipses, but it does not disappear completely. This suggests that the size of the variable optical emission source is comparable to that of the normal star whose size is therefore R_O \approx 2e12 cm \approx 30 R_sun. The decrease in flux variability amplitude during eclipses suggests the presence of a nonvariable optical emission component with a magnitude m_R=~13.2.

12 pages, 11 figures. Accepted for publication in Astronomy Letters. The original version in Russian is available at http://hea.iki.rssi.ru/rtt150/ru/ss433_pazh10/pss433_fast.pdf

References in corpus (9)

• The Nature of SS433 and the Ultraluminous X-ray Sources
• INTEGRAL observations of SS433: Results of coordinated campaign
• Identification of the Mass Donor Star's Spectrum in SS 433
• Spectroscopic Observations of the Mass Donor Star in SS 433
• The Brightest Black Holes
• Diagnostics of the black hole candidate SS433 with the RXTE
• Broad band variability of SS433: Accretion disk at work?
• A Massive Jet Ejection Event from the Microquasar SS 433 Accompanying Rapid X-Ray Variability
• First simultanous X-ray and optical observations of rapid variability of supercritical accretor SS433

Cited by in corpus (7)

• SS433: a massive X-ray binary at advanced evolutionary stage
• INTEGRAL observations of SS433: system's parameters and nutation of supercritical accretion disk
• X-ray variability of SS433: effects of the supercritical accretion disc
• X-ray Variability of SS 433: Evidence for Supercritical Accretion
• On the Change of the Inner Boundary of an Optically Thick Accretion Disk around White Dwarfs Using the Dwarf Nova SS Cyg as an Example
• Spectral and photometric variability of SS 433 observed with XRISM and simultaneous optical and near-infrared telescopes
• Search for isolated Galactic Centre stellar mass black holes in the IR and sub-mm range