Name of the Speaker(s): N.M.Shakhovskoy and Yu.S.Efimov
Institution: CRIMEAN ASTROPHYSICAL OBSERVATORY (Ukraine)
Title of the communication:
Helical structure of magnetic fields in blazar's jets
revealed by optical polarization observations.
Preliminary abstract (12 lines max.):
In terms of blazars shock-jet model the long sets of polarization
observations may reveal the type of magnetic field structure in jets.
One types of structure is helical field. The best example of field this
type give UBVRI polarization observations of OJ 287 obtained in Crimean
Observatory at its strong outburst in 1994-95. These observations show the
cyclic variations of observed position angles indicating the continuous
clockwise rotation of polarization plane of variable source with the speed
about 5 deg/day during 165 days. This is an evidence of the presence of
the helical magnetic field in the jet. The others cases of sporadic cyclic
variations of optical polarization in blazars we had found for OJ 287 in
its quiescent state in 1975, April (with the same direction of rotation)
and for PKS 0735+16 at the time of its strong outburst in 1977.