List of Figures

• I.1. Radio galaxy Cygnus A (3C 405)
• I.2. Model of a jet
• I.3. NGC1265, a galaxy with a prototype radio trail
• I.4. 3C 449 Radio Galaxy. Prototype of a mirror symmetric double radio source
• I.5. NGC 326 radio galaxy with inversion symmetry
• I.6. The quasar PKS 1318 + 113. Evidence of a jet-cloud interaction
• I.7. Evolution of small double radio sources and the alignment effect
• I.8. Evolution of large double radio sources and the alignment effect
• I.9. Emission line diagnostic plot for the aligned optical emission from 3CR radio galaxies
• II.1. Region of influence of small amplitude perturbations
• II.2. Transmission of perturbations in supersonic flow
• II.3. Comparison between classical and relativistic Mach numbers
• II.4. Schematic representation of a rarefaction wave
• III.1. Initial stages of a jet-cloud interaction
• III.2. 2D simulation of a Herbig-Haro jet colliding with a uniform density cloud
• III.3. Deflection of a jet due to a collision with an isothermal cloud. Classical case
• III.4. Deflection produced in a jet as it crosses a galaxy
• III.5. Deflection of a relativistic jet induced by passing through an isothermal cloud
• III.6. Trajectory of a relativistic jet as it crosses a galaxy
• III.7. Deflection angles of a jet as it passes through an isothermal cloud
• III.8. Variation of initial azimuthal angle of a relativistic jet as a function of velocity as it crosses a stratified density region
• IV.1. Relation between the velocity vector and certain given direction
• IV.2. Formation of shock waves in flows that turn through an angle
• IV.3. Sketch of a curved jet that develops a shock at the onset of the curvature
• IV.4. Generation of a shock at the start of the curvature of a jet
• V.1. Description of the problem in the rest frame of tangential discontinuities
• V.2. Pressure variation behind the transmitted shock into the cloud
• V.3. Pressure variation behind the transmitted shock into the external medium
• V.4. Description of the problem in a rest frame at infinity
• V.5. Variation of pressure and density as functions of time
• V.6. Variation of the width of the cloud as a function of time
• VI.1. Radio trail source 3C 129
• VI.2. Creation of a shock wave at the onset of a curvature
• VI.3. Radio galaxy 3C 31
• VI.4. Quasar 3C 175
• VI.5. Quasar 3C 334
• VI.6. 3C 34 Radio Galaxy: a jet-cloud interaction