1. SS 433: Distance Determination with Radio Images
Jared H. Crossley
14 May 2003
I gave this presentation was given for a Technical Writing course at New Mexico Tech. I have put this on my web site rather than the original presentation that I gave at NRAO because it reports on the work that I did with Michael Rupen after the end of my REU. The results presented here should be consistent with the AAS poster.

2. SS 433: Distance Determination
Outline
Introduction: SS 433 and W 50
Research question and thesis
The kinematic model of SS 433
Findings
Jet deceleration
Velocity-distance degeneracy
Conclusions
Study limitations and future work
14 May 2003
SS 433: Distance Determination
with Radio Images

3. SS 433: Distance Determination
Introduction
SS 433 was discovered in late 1970’s, very complex optical emission
Lies at the center of supernova remnant
W 50
Dubner, et al. (1998)
14 May 2003
SS 433: Distance Determination
with Radio Images

4. SS 433: Distance Determination
Intro continued…
One of the brightest X-ray binaries; only one with persistent evolving large scale radio jets
A kinematic model of jet structure was developed and revised over the past 20+ years
14 May 2003
SS 433: Distance Determination
with Radio Images

5. SS 433: Distance Determination
Research Question
Emission from W 50 places the system at a distance of 3 kiloparsecs (1 parsec = 3.3 light-years)
Fitting models of SS 433 to observed data results in a distance of 5 kpc.
Thesis
I show that the model-fitting method may be flawed, by providing evidence of
Jet deceleration, not accounted for
A velocity-distance degeracy
14 May 2003
SS 433: Distance Determination
with Radio Images

6. SS 433: Distance Determination
Model Parameters
P – precession period
t0 – time where precession phase is zero
v – speed of matter in beams
i – inclination of precession cone axis
θ – half opening angle of cone
D – distance to object
χ – position angle of cone axis
s – handedness of precession
δ – declination
14 May 2003
SS 433: Distance Determination
with Radio Images

7. SS 433: Distance Determination
Jet Deceleration
D = 4.8, 5, and 5.2 kpc
1.5 GHz VLBA
6 Mar 1998
15 GHz VLA
5 Mar 1998
16 Dec 1996
8.5 GHz VLA
13 Jan 1997
8.5 GHz VLA
14 May 2003
SS 433: Distance Determination
with Radio Images

8. Velocity-Distance Degeneracy
v/c = , D = 5 kpc
v/c = , D = 3 kpc
8.5 GHz VLA
16 Dec 1996
13 Jan 1997
15 GHz VLA
5 Mar 1998
1.5 GHz VLBA
6 Mar 1998
14 May 2003
SS 433: Distance Determination
with Radio Images

9. SS 433: Distance Determination
Conclusions
Evidence of jet deceleration with distance from the core
Velocity-distance degeneracy exists in the model
Distances obtained from spatial modeling of jet structure must be re-evaluated
14 May 2003
SS 433: Distance Determination
with Radio Images

10. Limitations & Future Work
This study was limited by using only four epochs of observations
Further corroboration of the above results should employ a larger number of epochs, distributed evenly in jet phase
Thanks to Michael Rupen, Vivek Dhawan, and Amy Mioduszewski (NRAO) for their help with this project.
14 May 2003
SS 433: Distance Determination
with Radio Images