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Atmospheric Azimuthal Asymmetry & It’s Consequences . John Gipson East Coast VLBI Meeting 18 October 2005. 2Cot(el). EL. Distance Between Rays. H. Simulation. Point position. Estimate U,E,N, Clk, Atm for one station. U,E,N had 1 parameter for entire session.
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Atmospheric Azimuthal Asymmetry & It’s Consequences John Gipson East Coast VLBI Meeting 18 October 2005
2Cot(el) EL Distance Between Rays H
Simulation • Point position. Estimate U,E,N, Clk, Atm for one station. • U,E,N had 1 parameter for entire session. • Clks, Atms, piece linear with 20 minute rate breaks. • 500 observations evenly spaced in time. • Uniform (random) distribution above cutoff.
Simulation (cont) • Constant noise 20ps=6 mm. Proxy for what we do now. • Constant noise+1.56 cot(el) mm. Include atmosphere. • Noise=1.56 cot(el) mm. Perfect observations.