# galpy.df.impulse_deltav_hernquist_curvedstream¶

galpy.df.impulse_deltav_hernquist_curvedstream(v, x, b, w, x0, v0, GM, rs)[source]

NAME:

impulse_deltav_plummer_hernquist

PURPOSE:

calculate the delta velocity to due an encounter with a Hernquist sphere in the impulse approximation; allows for arbitrary velocity vectors, and arbitrary position along the stream

INPUT:

v - velocity of the stream (nstar,3)

x - position along the stream (nstar,3)

b - impact parameter

w - velocity of the Hernquist sphere (3)

x0 - point of closest approach

v0 - velocity of point of closest approach

GM - mass of the Hernquist sphere (in natural units)

rs - size of the Hernquist sphere

OUTPUT:

deltav (nstar,3)

HISTORY:

2015-08-13 - SANDERS, using Wyn Evans calculation