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ATEL # 882; A. Skopal, T. Pribulla (Astronomical Institute of the Slovak Academy of Sciences, Tatranska Lomnica)
on 14 Sep 2006; 13:56 UT
Password Certification: Augustin Skopal (firstname.lastname@example.org)
Subjects: Optical, Binaries, Cataclysmic Variables
We report on the current major outburst of the symbiotic prototype Z And and the discovery of spectral signatures of collimated bipolar jets observed at/after its optical maximum.
Our UBVRc photometry taken at the Observatories of the Astronomical Institute of the Slovak Academy of Sciences showed a gradual increase in the star's brightness from 2006 April 07 (9.86, 10.94, 10.29 and 9.27) to 2006 July 19, when Z And peaked at 8.06, 8.94, 8.58 and 8.10 in the U, B, V and Rc passband, respectively. This was the highest maximum that has ever been recorded by the multicolor photometry (from 1983) to date.
On 2006 August 30.19 UT we obtained high-resolution spectra of Z And (R = 11000) at the David Dunlop Observatory, University of Toronto, with 1.88-m telescope in the ranges of 6430-6700A and 4620-4915A. The hydrogen H-alpha and H-beta lines showed a strong central emission component located around the reference wavelengths, which were accompanied by weaker satellite emission components at -1260(11) and +1210(11) km/s in both the lines. Integrated fluxes of these jet emissions were 5.4(0.6) and 2.3(0.5) x 1.0E-12 erg sE-1 cmE-2 in H-alpha and H-beta, respectively. FWHM of the violet jet's emission was 183(10) km/s and that of the red one was 204(10) km/s. In addition, a strong absorption component in the H-beta and HeI 4713A profiles was measured at about -150 and -90 km/s, respectively. Radial velocities are heliocentric. Signatures of the bipolar jets in the Z And optical spectrum were the first ever recorded for this system.