Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2011-08-15
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
8 pages, 6 figures, accepted to MNRAS
Scientific paper
We explore a ballistic orbit model to infer the gravitational drag force on an accreting point mass M, such as a black hole, moving at a hypersonic velocity v_{0} through a gaseous environment of density \rho_{0}. The streamlines blend in the flow past the body and transfer momentum to it. The total drag force acting on the body, including the nonlinear contribution of those streamlines with small impact parameter that bend significantly and pass through a shock, can be calculated by imposing conservation of momentum. In this fully analytic approach, the ambiguity in the definition of the lower cut-off distance $r_{\rm min}$ in calculations of the effect of dynamical friction is removed. It turns out that $r_{\rm min}=\sqrt{e}GM/2v_{0}^{2}$. Using spherical surfaces of control of different sizes, we carry out a successful comparison between the predicted drag force and the one obtained from a high resolution, axisymmetric, isothermal flow simulation. We demonstrate that ballistic models are reasonably successful in accounting for both the accretion rate and the gravitational drag.
Cantó Jorge
Esquivel Alejandro
Raga Alejandro C.
Sanchez-Salcedo Javier F.
No associations
LandOfFree
Gravitational drag on a point mass in hypersonic motion through a gaseous medium does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Gravitational drag on a point mass in hypersonic motion through a gaseous medium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Gravitational drag on a point mass in hypersonic motion through a gaseous medium will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-302113