Mv Lyr: Transition from Low to High Brightness State

We present results of multicolour photometry of the nova-like binary MV Lyr in the years 2002–2003, corresponding to the transition of the star from its low (V = 17.8) to high (V = 12.3) brightness state. The transition lasted at most 200 days. During the first ∼50 days MV Lyr brightened at the rate 0.06 mag/day, and during the next ∼150 days at the rate 0.01 mag/day. The brightening was accompanied by a blue shift from 0.45 to 0.05 in V−R, interpreted as an increase of the accretion disk contribution to the total light. During the transition MV Lyr displayed well-known ‘quasi-orbital’ light variations and fast quasi-periodic oscillations with a typical time scale of tens of minutes.     

Spectral and photometric studies of polar CRTS CSS 130604 J 215427+155714

We present the results of spectroscopic and photometric studies of a new polar CRTS CSS130604 J 215427+155714, conducted at the telescopes of the SAO RAS. Analysis of the photometric series of observations allowed to clarify the orbital period of the system, P _o = 0_. ^d 0672879 (±0.0000003). We build radial velocity curves and trace the intensity variations in the Hβ and H_γ hydrogen lines and He II λ 4686 ?A ionized heliumline. Based on the Hβ and He II lines we build Doppler maps. It is shown that the line formation region is localized near the Lagrange point. The following parameter estimates of the system are obtained:M ₁ = 0.83 ± 0.10M _⊙, M ₂ = 0.15 ± 0.01M _⊙, q = M ₂/M ₁ = 0.18 ± 0.03, i = 53? ± 5?. Based on the results of spectral, photometric and previously published polarimetric observations the possible geometric model of the system is discussed.