Elementary processes in astrophysics (NAST024)

Accretion onto moving object

Depending on the approach, this mode of accretion is commonly called Bondi-Hoyle or Bondi-Hoyle-Lyttleton accretion. We will follow the simplest possible one which is based on motion of incoherent particles. Hydrodynamics in this model is implemented by an assumption that particles collide beyond the moving object (a star) at the symmetry axis, losing the tangential component of momentum while keeping the radial one.

The relevant part of the textbook by Vladimir Karas is Section 4.2. Some derivations, radial velocity of the particle on the axis in particular, can be found in my hand-notes.

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