def peculiar(ra, dec, d, pm_ra, pm_dec, V):
o = Orbit([ra * u.deg, dec * u.deg, d * u.kpc, pm_ra * u.mas / u.yr, pm_dec * u.mas / u.yr, V * u.km / u.s],
radec=True)
o2 = Orbit(vxvv=[o.R(0.) / 8.0, 0., 1., 0., 0., o.phi(0.)], ro=8., vo=220.)
current_vel = np.sqrt(
(o.U(0.) - o2.U(0) + 11.1) ** 2 + (o.V(0.) - o2.V(0) + 12.24) ** 2 + (o.W(0.) - o2.W(0) + 7.25) ** 2)
return current_vel
def test_correctInitialSolarMotion():
age = np.pi # Half a galactic revolution
# For reference: the expected solar motion as provided by Schoenrich
REFERENCE_SCHOENRICH_SOLAR_MOTION = np.array([-11.1, -12.24, -7.25])
ntimesteps = 10
# vxvv is in cylindrical coordinates here. [R,vR,vT(,z,vz,phi)]
lsr_orbit = Orbit(vxvv=[1, 0, 1, 0, 0, 0],
vo=220,
ro=8,
solarmotion='schoenrich')
lsr_orbit.integrate(np.linspace(0., age, ntimesteps), MWPotential2014)
U = lsr_orbit.U(0)
V = lsr_orbit.V(0)
W = lsr_orbit.W(0)
results = np.array([U, V, W]).reshape(3)
for i, vel in enumerate('UVW'):
print("For velocity {}:".format(vel))
print(" expected: {}".format(REFERENCE_SCHOENRICH_SOLAR_MOTION[i]))
print(" received: {}".format(results[i]))
assert (np.allclose(REFERENCE_SCHOENRICH_SOLAR_MOTION, results)),\
'!!! Using galpy version {} Need galpy version 1.1 !!!'.format(
galpy.__version__
)
def pass_v(ra, dec, d, pm_ra, pm_dec, V, time, numpoints):
o = Orbit([ra * u.deg, dec * u.deg, d * u.kpc, pm_ra * u.mas / u.yr, pm_dec * u.mas / u.yr, V * u.km / u.s],
radec=True)
lp = MWPotential2014
ts = np.linspace(0, time, numpoints) * u.Gyr
o.integrate(ts, lp)
pass_t_array = ts[np.where(np.sign(o.z(ts)[:-1]) - np.sign(o.z(ts)[1:]) != 0)[0]]
results = []
for pass_t in pass_t_array:
o2 = Orbit(vxvv=[o.R(pass_t) / 8.0, 0., 1., 0., 0., o.phi(pass_t)], ro=8., vo=220.)
# results.append(np.sqrt((o.U(pass_t)-o2.U(0)+11.1)**2 + (o.V(pass_t)-o2.V(0)+12.24)**2 + (o.W(pass_t)-o2.W(0)+7.25)**2))
results.append(
np.sqrt((o.U(pass_t) - o2.U(0)) ** 2 + (o.V(pass_t) - o2.V(0)) ** 2 + (o.W(pass_t) - o2.W(0)) ** 2))
return results
def pec_v(ra, dec, d, pm_ra, pm_dec, V):
"""
Function to estimate system peculiar velocity distribution as a function of distance.
ra,dec,d,pm_ra,pm_dec,V are source orbit parameters for Galpy
numpoints is the number of points in the orbit to integrate.
"""
o = Orbit([
ra * u.deg, dec * u.deg, d * u.kpc, pm_ra * u.mas / u.yr,
pm_dec * u.mas / u.yr, V * u.km / u.s
],
radec=True)
o2 = Orbit(vxvv=[o.R(0.) / 8.0, 0., 1., 0., 0., o.phi(0.)], ro=8., vo=220.)
current_vel = np.sqrt((o.U(0.) - o2.U(0) + 11.1)**2 +
(o.V(0.) - o2.V(0) + 12.24)**2 +
(o.W(0.) - o2.W(0) + 7.25)**2)
return current_vel
def pass_v(ra, dec, d, pm_ra, pm_dec, V, time, numpoints):
"""
Function to estimate system velocity everytime it passes through the galactic plane.
This velocity is a proxy for system's natal kick. For details, assumptions and caveats
see Atri et al. 2019.
-----
ra,dec,d,pm_ra,pm_dec,V are source orbit parameters for Galpy
time is the age to integrate (Gyr)
numpoints is the number of points in the orbit to integrate.
"""
o = Orbit([
ra * u.deg, dec * u.deg, d * u.kpc, pm_ra * u.mas / u.yr,
pm_dec * u.mas / u.yr, V * u.km / u.s
],
radec=True)
lp = MWPotential2014
ts = np.linspace(0, time, numpoints) * u.Gyr
o.integrate(ts, lp)
pass_t_array = ts[np.where(
np.sign(o.z(ts)[:-1]) - np.sign(o.z(ts)[1:]) != 0)[0]]
results = []
for pass_t in pass_t_array:
o2 = Orbit(vxvv=[o.R(pass_t) / 8.0, 0., 1., 0., 0.,
o.phi(pass_t)],
ro=8.,
vo=220.)
#results.append(np.sqrt((o.U(pass_t)-o2.U(0)+11.1)**2 + (o.V(pass_t)-o2.V(0)+12.24)**2 + (o.W(pass_t)-o2.W(0)+7.25)**2))
results.append(
np.sqrt((o.U(pass_t) - o2.U(0))**2 + (o.V(pass_t) - o2.V(0))**2 +
(o.W(pass_t) - o2.W(0))**2))
return results
def integrate_xyzuvw(params, times, lsr_orbit=None, Potential=MWPotential2014):
"""Convenience function. Integrates the motion of a star backwards in time.
Parameters
----------
params: numpy array
Kinematic parameters (RAdeg,DEdeg,Plx,pmRA,pmDE,RV)
ts: times for back propagation, in Myr.
lsr_orbit:
WARNING: messy...
lsr_orbit= Orbit(vxvv=[1.,0,1,0,0.,0],vo=220,ro=8, solarmotion='schoenrich')
lsr_orbit.integrate(ts,MWPotential2014,method='odeint')
MWPotential2014:
WARNING: messy...
from galpy.potential import MWPotential2014
"""
#We allow MWPotential and lsr_orbit to be passed for speed, but can compute/import
#now.
if not lsr_orbit:
lsr_orbit = get_lsr_orbit(times)
#Convert times to galpy units:
ts = -(times / 1e3) / bovy_conversion.time_in_Gyr(220., 8.)
params = np.array(params)
vxvv = params.copy()
#We'd prefer to pass parallax in mas, but distance in kpc is accepted. This
#reciporical could be done elsewhere...
vxvv[2] = 1.0 / params[2]
o = Orbit(vxvv=vxvv, radec=True, solarmotion='schoenrich')
o.integrate(ts, Potential) #,method='odeint')
xyzuvw = np.zeros((len(ts), 6))
xyzuvw[:, 0] = 1e3 * (o.x(ts) - lsr_orbit.x(ts))
xyzuvw[:, 1] = 1e3 * (o.y(ts) - lsr_orbit.y(ts))
#The lsr_orbit is zero in the z direction by definition - the local standard of
#rest is at the midplane of the Galaxy
xyzuvw[:, 2] = 1e3 * (o.z(ts))
#UVW is relative to the sun. We *could* have used vx, vy and vz. Would these
#have been relative to the LSR?
xyzuvw[:, 3] = o.U(ts) - lsr_orbit.U(ts)
xyzuvw[:, 4] = o.V(ts) - lsr_orbit.V(ts)
xyzuvw[:, 5] = o.W(ts) - lsr_orbit.W(ts) #NB This line changed !!!
return xyzuvw
def trace_forward(xyzuvw,
time_in_past,
Potential=MWPotential2014,
solarmotion=None):
"""Trace forward one star in xyzuvw coords
Parameters
----------
xyzuvw: numpy float array
xyzuvw relative to the local standard of rest at some point in the past.
time_in_past: float
Time in the past that we want to trace forward to the present.
"""
if solarmotion == None:
xyzuvw_sun = np.zeros(6)
elif solarmotion == 'schoenrich':
xyzuvw_sun = [0, 0, 25, 11.1, 12.24, 7.25]
else:
raise UserWarning
if time_in_past == 0:
time_in_past = 1e-5
# print("Time in past must be nonzero: {}".format(time_in_past))
# raise UserWarning
times = np.linspace(0, time_in_past, 2)
# Start off with an LSR orbit...
lsr_orbit = get_lsr_orbit(times)
# Convert times to galpy units:
ts = -(times / 1e3) / bovy_conversion.time_in_Gyr(220., 8.)
# Add on the lsr_orbit to get the times in the past.
xyzuvw_gal = np.zeros(6)
xyzuvw_gal[0] = xyzuvw[0] / 1e3 + lsr_orbit.x(ts[-1]) - lsr_orbit.x(ts[0])
xyzuvw_gal[1] = xyzuvw[1] / 1e3 + lsr_orbit.y(ts[-1]) - lsr_orbit.y(ts[0])
# Relative to a zero-height orbit, excluding the solar motion.
xyzuvw_gal[2] = xyzuvw[2] / 1e3
xyzuvw_gal[3] = xyzuvw[3] + lsr_orbit.U(ts[-1]) - lsr_orbit.U(ts[0])
xyzuvw_gal[4] = xyzuvw[4] + lsr_orbit.V(ts[-1]) - lsr_orbit.V(ts[0])
xyzuvw_gal[5] = xyzuvw[5] + lsr_orbit.W(ts[-1]) - lsr_orbit.W(ts[0])
# Now convert to units that galpy understands by default.
# FIXME: !!! Reverse [0] sign here.
l = np.degrees(np.arctan2(xyzuvw_gal[1], -xyzuvw_gal[0]))
b = np.degrees(
np.arctan2(xyzuvw_gal[2], np.sqrt(np.sum(xyzuvw_gal[:2]**2))))
dist = np.sqrt(np.sum(xyzuvw_gal[:3]**2))
# As we are already in LSR co-ordinates, put in zero for solar motion and
# zo.
o = Orbit([l, b, dist, xyzuvw_gal[3], xyzuvw_gal[4], xyzuvw_gal[5]],
solarmotion=[0, 0, 0],
zo=0,
lb=True,
uvw=True,
vo=220,
ro=8)
# Integrate this orbit forwards in time.
o.integrate(-ts, Potential) # ,method='odeint')
# Add in the solar z and the solar motion.
xyzuvw_now = np.zeros(6)
xyzuvw_now[0] = 1e3 * (o.x(-ts[-1]) - lsr_orbit.x(0))
xyzuvw_now[1] = 1e3 * o.y(-ts[-1])
xyzuvw_now[2] = 1e3 * o.z(-ts[-1]) - xyzuvw_sun[2]
xyzuvw_now[3] = o.U(-ts[-1]) - xyzuvw_sun[3]
xyzuvw_now[4] = o.V(-ts[-1]) - xyzuvw_sun[4]
xyzuvw_now[5] = o.W(-ts[-1]) - xyzuvw_sun[5]
# pdb.set_trace()
return xyzuvw_now
def estimate_orbit_parameters(star_index, orbit_calculation_input):
"""
Estimate orbit parameters from the given
MC sample of 6D information for the Nr of stars
and save it into orbit_information
"""
# We are creating a dictionary for each star
star_i = dict()
ra = orbit_calculation_input['ra'] *u.deg
dec = orbit_calculation_input['dec'] *u.deg
dist = orbit_calculation_input['distance'] *u.pc
pm_ra = orbit_calculation_input['pmra'] *u.mas/u.year
pm_dec = orbit_calculation_input['pmdec'] *u.mas/u.year
v_los = orbit_calculation_input['vrad'] *u.km/u.s
# Create the Orbit instance
o = Orbit(
vxvv=[ra,dec,dist,pm_ra, pm_dec,v_los],
ro=r_galactic_centre,
vo=v_circular,
zo=z_galactic_plane,
solarmotion=[-11.1, 15.17, 7.25]*u.km/u.s,
radec=True
)
star_i = dict()
#Galactocentric coordinates:
star_i['X_XYZ'] = o.helioX()#*u.kpc
star_i['Y_XYZ'] = o.helioY()#*u.kpc
star_i['Z_XYZ'] = o.helioZ()#*u.kpc
star_i['U_UVW'] = o.U()#*u.km/u.s
star_i['V_UVW'] = o.V()#*u.km/u.s
star_i['W_UVW'] = o.W()#*u.km/u.s
star_i['R_Rzphi'] = o.R()#*u.kpc
star_i['phi_Rzphi'] = o.phi()#*u.rad
star_i['z_Rzphi'] = o.z()#*u.kpc
star_i['vR_Rzphi'] = o.vR()#*u.km/u.s
star_i['vT_Rzphi'] = o.vT()#*u.km/u.s
star_i['vz_Rzphi'] = o.vz()#*u.km/u.s
try:
star_i['J_R'], star_i['L_Z'],star_i['J_Z'], star_i['omega_R'], star_i['omega_phi'], star_i['omega_z'], star_i['angle_R'], star_i['angle_phi'], star_i['angle_z'] = aAS.actionsFreqsAngles(
#R,vR,vT,z,vz[,phi]
star_i['R_Rzphi']*u.kpc,
star_i['vR_Rzphi']*u.km/u.s,
star_i['vT_Rzphi']*u.km/u.s,
star_i['z_Rzphi']*u.kpc,
star_i['vz_Rzphi']*u.km/u.s,
star_i['phi_Rzphi']*u.rad,
ro=r_galactic_centre,vo=v_circular
)
except:
star_i['omega_R'] = [np.nan]
star_i['omega_phi'] = [np.nan]
star_i['omega_z'] = [np.nan]
star_i['angle_R'] = [np.nan]
star_i['angle_phi'] = [np.nan]
star_i['angle_z'] = [np.nan]
try:
star_i['J_R'], star_i['L_Z'],star_i['J_Z'] = aAS(
#R,vR,vT,z,vz[,phi]
star_i['R_Rzphi']*u.kpc,
star_i['vR_Rzphi']*u.km/u.s,
star_i['vT_Rzphi']*u.km/u.s,
star_i['z_Rzphi']*u.kpc,
star_i['vz_Rzphi']*u.km/u.s,
star_i['phi_Rzphi']*u.rad,
ro=r_galactic_centre,vo=v_circular
)
except:
star_i['J_R'] = [np.nan]
star_i['L_Z'] = [np.nan]
star_i['J_Z'] = [np.nan]
try:
star_i['ecc'], star_i['zmax'], star_i['R_peri'], star_i['R_ap'] = aAS.EccZmaxRperiRap(
#R,vR,vT,z,vz[,phi]
star_i['R_Rzphi']*u.kpc,
star_i['vR_Rzphi']*u.km/u.s,
star_i['vT_Rzphi']*u.km/u.s,
star_i['z_Rzphi']*u.kpc,
star_i['vz_Rzphi']*u.km/u.s,
star_i['phi_Rzphi']*u.rad,
ro=r_galactic_centre,vo=v_circular
)
star_i['zmax']
star_i['R_peri']
star_i['R_peri']
except:
star_i['ecc'] = [np.nan]
star_i['zmax'] = [np.nan]
star_i['R_peri'] = [np.nan]
star_i['R_ap'] = [np.nan]
star_i['Energy'] = o.E(pot=pot,ro=r_galactic_centre,vo=v_circular,zo=z_galactic_plane)
return(star_i)
#ra, dec, dist, pm_ra, pm_dec, v_los
vxvv=[0.*u.deg,0.*u.deg,0.*u.kpc,0.*u.mas/u.yr, 0.*u.mas/u.yr,0.*u.km/u.s],
ro=r_galactic_centre,
vo=v_circular,
zo=z_galactic_plane,
solarmotion=[-11.1, 15.17, 7.25]*u.km/u.s,
#solarmotion='schoenrich',
radec=True
)
#Galactocentric coordinates:
sun['X_XYZ'] = o.helioX()#*u.kpc
sun['Y_XYZ'] = o.helioY()#*u.kpc
sun['Z_XYZ'] = o.helioZ()#*u.kpc
sun['U_UVW'] = o.U()#*u.km/u.s
sun['V_UVW'] = o.V()#*u.km/u.s
sun['W_UVW'] = o.W()#*u.km/u.s
sun['R_Rzphi'] = o.R()#*u.kpc
sun['phi_Rzphi'] = o.phi()#*u.rad
sun['z_Rzphi'] = o.z()#*u.kpc
sun['vR_Rzphi'] = o.vR()#*u.km/u.s
sun['vT_Rzphi'] = o.vT()#*u.km/u.s
sun['vz_Rzphi'] = o.vz()#*u.km/u.s
try:
sun['J_R'], sun['L_Z'],sun['J_Z'], sun['omega_R'], sun['omega_phi'], sun['omega_z'], sun['angle_R'], sun['angle_phi'], sun['angle_z'] = aAS.actionsFreqsAngles(
#R,vR,vT,z,vz[,phi]
sun['R_Rzphi']*u.kpc,
sun['vR_Rzphi']*u.km/u.s,
sun['vT_Rzphi']*u.km/u.s,
sun['z_Rzphi']*u.kpc,
if 'rv' in o_data.keys(): o_data['rv'] = o.vlos(ts) if 'x' in o_data.keys(): o_data['x'] = o.x(ts) if 'y' in o_data.keys(): o_data['y'] = o.y(ts) if 'z' in o_data.keys(): o_data['z'] = o.z(ts) if 'r' in o_data.keys(): o_data['r'] = o.R(ts) if 'phi' in o_data.keys(): o_data['phi'] = o.phi(ts) if 'vx' in o_data.keys(): o_data['vx'] = o.vx(ts) if 'vy' in o_data.keys(): o_data['vy'] = o.vy(ts) if 'vz' in o_data.keys(): o_data['vz'] = o.vz(ts) if 'vr' in o_data.keys(): o_data['vr'] = o.vR(ts) if 'vphi' in o_data.keys(): o_data['vphi'] = o.vT(ts) if 'U' in o_data.keys(): o_data['U'] = o.U(ts) if 'V' in o_data.keys(): o_data['V'] = o.V(ts) if 'W' in o_data.keys(): o_data['W'] = o.W(ts) if 'l' in o_data.keys(): o_data['l'] = o.ll(ts) if 'b' in o_data.keys(): o_data['b'] = o.bb(ts) if 'pml' in o_data.keys(): o_data['pml'] = o.pmll(ts) if 'pmb' in o_data.keys(): o_data['pmb'] = o.pmbb(ts) ################################################################################ # SAVE DATA #################################################################### savefiles = not args.notsave # Prepare savefile savedir = args.savedir
