set_flyby

Module

Description

This module is contains utilities for setting up flyby. Our conventions for angles are the same as in Xiang-Gruess (2016). Eccentricity is set to unity, i.e. for a parabolic orbit:

• minimum_approach : distance of minimum approach (pericentre)

• initial_dist : the initial separation distance (in units of minimum_approach)

• posang_ascnode : angle counter-clockwise (East) from y-axis (North)

• inclination : angle of rotation of orbital plane around axis defined by the position angle (for posang_ascnode=0 this is a roll angle)

References:

• Xiang-Gruess (2016), MNRAS 455, 3086-3100

• Cuello et al. (2019), MNRAS 483, 4114-4139

Owner:

Daniel Mentiplay

Runtime parameters:

None

Dependencies:

physcon, vectorutils

Quick access

Variables:

ierr_ecc, ierr_m1, ierr_m2, ierr_peri

Routines:

get_t_flyby(), set_flyby()

Needed modules

• physcon (pi()): Physical and mathematical constants (as in sphNG)

Variables

• setflyby/ierr_ecc [integer,private/parameter/optional/default=3]

• setflyby/ierr_m1 [integer,private/parameter/optional/default=1]

• setflyby/ierr_m2 [integer,private/parameter/optional/default=2]

• setflyby/ierr_peri [integer,private/parameter/optional/default=4]

Subroutines and functions

subroutine  setflyby/set_flyby(m1, m2, minimum_approach, initial_dist, accretion_radius1, accretion_radius2, xyzmh_ptmass, vxyz_ptmass, nptmass, ierr[, posang_ascnode[, inclination[, verbose]]])

Parameters:

• m1 [real,in]

• m2 [real,in]

• minimum_approach [real,in]

• initial_dist [real,in]

• accretion_radius1 [real,in]

• accretion_radius2 [real,in]

• xyzmh_ptmass (,) [real,inout]

• vxyz_ptmass (,) [real,inout]

• nptmass [integer,inout]

• ierr [integer,out]

• posang_ascnode [real,in,]

• inclination [real,in,]

• verbose [logical,in,]

Use :

vectorutils (rotatevec())

Call to:

rotatevec()

function  setflyby/get_t_flyby(m1, m2, dma, n0)

Parameters:

• m1 [real,in]

• m2 [real,in]

• dma [real,in]

• n0 [real,in]

Return:

t [real]