SS433 / W50 – still an enigma ! History SS433 main properties Modeling the jets Physical parameters and problems ! Interaction of a jet with its surrounding How is the power transferred to W50 ?
Milestones 1978 – 1982 discovery, models, optical work 1983 Einstein EXOSAT 1987 – 1991 Ginga 1992 – 2000 Asca ……. Chandra 2001 – ……. XMM Newton
Some history Catalog by Stephenson & Sanduleak (1977) ‘discovery’ by Margon in October 1978 Kinematical model by Fabian&Rees, Milgrom, Abell&Margon (1979) Until 1982 about 1500 ‘optical’ papers; at Google hits 1983 Einstein picture of W50 in X-rays
Properties of the binary system P orb = days P prec = 162 days i = 78.8 degrees = 19 degrees Short term jitter, flicker, … Long term stable ! What kind of stars (masses) ???
Exosat observations 1984/86
Early Chandra observations
XMM – Newton observations
XMM - Newton
Modeling the jet emission (1D / 2D) Base of jet: T o, n o, r o, chemical abundances Fixed: v j et, opening angle of jet Calculate hydrodynamic evolution along jet; ionization structure, emitted spectra, and total emission (normalization!) Then: blue- / redshift the spectrum Fit this spectrum to XMM data
In eclipse !
Missing flux: 2 possibilities
X-ray jet as probe in the system! A jet model fitting the source in and out of eclipse will provide the geometrical parameters of the binary !!! What is kown so far about the system ? A3-7I-star (Gies & Hillwig), masses ? (Kx, Kv, …)
ALL parameter determinations rely on modeling ! Optical: where does the light come from ? Which lines to use? Strong variability. Roche lobe geometry. X-rays: jet model (conical, stationary flow). Extra component of emission !
Parameters of the binary
Modelling the Asca light curve: Take a jet model: n o, T o, r o jet length, flux Adjust parameters to get flux out of eclipse Eclipse the jet by star Depth of eclipse: relative star radius Duration of eclipse: ratio R/a Take other X-ray energy band ……… and so on …..
blue: R/a = 0.57 green: R/a = 0.5
Parameters for that model: kT = 20 keV No = 1.0 e12 1/cm**3 R/a = 0.57 R = 1.4 e12 cm BUT: does not work for 2-5 keV band !! !! X-ray eclipse observations needed !!
VLA observation of the inner jets
Cut along the rotation axis
RESULTS: 1. Power law with gamma= Thermal with kT ~ 0.3 keV 3. Thermal component fills all the remnant 4. Refocussing and ‘deflection’ of jet 5. How is the jet-energy transferred to particles? 6. Where is all the energy going ? 7. Connection to radio (VLA!)
Brems – fit (14 keV) o.o.e.