Summary of Astrophyiscal Papers
relating to Jets.
The Time-dependent ejection velocity histories of HH34 and HH111
Raga, Velazquez, Canto and Masciadri 2002
HH34 and HH111 have similarities in their lobes. Well aligned chain of knots, ending in well defined bow shocks.
Derive the past ejection velocity histories from previous results.
Compute axisymmetric gasdynamical simulations of the two flows and find bow shocks at the correct postions.
Have assumed time-independent density at the base of the jet.
Proves that bow shocks are result of time-varying ejection velocity.
The observed large bow shock for HH34 can be reproduced by choosing an appropriate value for the density of the ambient medium.
From these results they attempt to make some statement about the general nature of these variabilities.
Different modes in action. Suggest that there are at least two different mechanisms producing the velocity variation.
Provide important constraints on future jet models.