Transient jets in the symbiotic prototype Z Andromedae
  We present development of the collimated bipolar jets from the symbiotic prototype Z And that appeared and disappeared during its 2006 outburst. In 2006 July Z And reached its historical maximum at U ~ 8.0. During this period, rapid photometric variations with Dm ~ 0.06 mag on the timescale of hours developed. Simultaneously, high-velocity satellite components appeared on both sides of the H-alpha and H-beta emission line profiles. They were launched asymmetrically with the red/blue velocity ratio of 1.2 - 1.3. From about mid-August they became symmetric. Their spectral properties indicated ejection of bipolar jets collimated within an average opening angle of 6.1 degrees. We estimated average outflow rate via jets to dM(jet)/dt ~ 2xE10-6(R(jet)/1AU)**(1/2) M(Sun)/year, during their August - September maximum, which corresponds to the emitting mass in jets, M(jet, emitting) ~ 6xE-10(Rjet)/1AU)^{3/2} M(Sun). During their lifetime, the jets released the total mass of M(jet, total) approx 7.4x1E-7 M(Sun). Evolution in the rapid photometric variability and asymmetric ejection of jets around the optical maximum can be explained by a disruption of the inner parts of the disk caused by radiation-induced warping of the disk. 
A. Skopal (1), T. Pribulla (1), J. Budaj (1), A. A. Vittone (2), L.   Errico (2), M. Wolf (3), M. Otsuka (4), M. Chrastina (...