apps120803_jdcfly.app08_jdc_jna_flyover
ΒΆ
A very simple exercise to observe Maxwell distributed SW by JCD/JNA over half the orbit.
''' A very simple exercise to observe Maxwell distributed SW by JCD/JNA over half the orbit.
'''
import os
import sys
import logging
logging.basicConfig()
import datetime
import math
import matplotlib.pyplot as plt
import matplotlib.ticker
import numpy as np
import scipy as sp
from irfpy.util.maxwell import mkfunc
import irfpy.util.intersection
import irfpy.jdc.energy0 as energy
import irfpy.jdc.fov0 as fov
import irfpy.jdc.frame0 as frame
import irfpy.jdc.flux0
import irfpy.jna.fov0 as jnafov
import irfpy.jna.frame0 as jnaframe
import irfpy.pep.pep_attitude as att
import irfpy.pep.mhddata
from .app05_op_longitude import get_dflux2
def main(pp=None, longitude=180., r=1.2, type="footprint"):
## Orbit around Ganymede.
ndiv = 360
posthetas = np.linspace(np.pi / 2., np.pi * 5 / 2., ndiv) # Only dayside
posphi = longitude * np.pi / 180. # For the first trial, Noon-midnight meridian is taken.
vmin = 4e-1
vmax = 1e+1
m = 16 * 1.67e-27
q = 1.60e-19
# For plotting
fig = plt.figure(figsize=(15, 10))
nullfmt = matplotlib.ticker.NullFormatter()
# For JNA
# Precipitation data
precip = irfpy.pep.mhddata.PrecipitationFlux(type=type)
lons = precip.reshape(precip.lonlist())
lats = precip.reshape(precip.latlist())
flx = precip.reshape(precip.flist()) # Flux at the surface.
sc = att.NadirLookingSc()
jnaflx = np.zeros((ndiv, 7)) + np.nan
for ilat in range(ndiv):
# For JNA
postheta = posthetas[ilat] # Position of S/C
# S/C position
pos = np.array([np.cos(postheta) * np.cos(posphi), np.cos(postheta) * np.sin(posphi), np.sin(postheta)])
pos = pos * r
# S/C Velocity direction.
vel = np.array([-np.sin(postheta) * np.cos(posphi), -np.sin(postheta) * np.sin(posphi), np.cos(postheta)])
# S/C instance
sc.set_posvel(pos, vel)
# Conversion.
for ch in (1, 2, 3, 4, 5): # Only center 5 channels.
# Center direction
az = jnafov.azim_pix_center(ch)
el = jnafov.elev_pix_center(ch)
vecjna = jnaframe.angles2jna(el, az)
vecnsc = jnaframe.jna2nsc(vecjna)
vecgan = sc.convert_to_ref(vecnsc) # Looking vector in Ganymede coordinates.
v2 = irfpy.util.intersection.los_sphere(pos, vecgan, [0, 0, 0], 1.)
if v2 == None:
continue
longit = np.arctan2(v2[1], v2[0]) * 180. / np.pi
latit = np.arcsin(v2[2]) * 180. / np.pi
idxlon, idxlat = precip.nearest_neighbor(longit, latit)
jnaflx[ilat, ch] = flx[idxlon, idxlat] * 0.2 / (2 * np.pi) * 2e-6 # in /s. Indeed, count rate
# 0.2 comes from 20% from CENA result.
# Sensor g-factor is taken from proposal v0.3, 2e-6 cm2 sr/pixel.
print(jnaflx[ilat, ch])
ax2 = fig.add_subplot(212)
xax = np.linspace(0, 360, ndiv + 1)
yax = np.arange(8)
x, y = np.meshgrid(xax, yax)
img = ax2.pcolor(x, y, np.ma.log10(jnaflx).T, vmin=np.log10(vmin), vmax=np.log10(vmax))
ax2.set_xlim(0, 360)
ax2.set_ylim(0, 7)
ax2.set_xlabel('Angle (North pole=0)')
ax2.set_ylabel('Direction')
fig.colorbar(img)
# FOR JDC
vmin = 1e-1
vmax = 6e+4
# ndiv = 360 # High resolution
ndiv = 8 # For debug
# Now, this is to save the data.
dfluxall = np.zeros([16, ndiv, 128]) - np.nan # 16 is for number of panels
if pp == None:
pp = irfpy.pep.mhddata.PlasmaParameter1205()
for ilat in range(ndiv):
# For JDC
postheta = posthetas[ilat]
pos = np.array([np.cos(postheta) * np.cos(posphi), np.cos(postheta) * np.sin(posphi), np.sin(postheta)])
pos = pos * r
n, vx, vy, vz, temp, pth = pp.interpolate3d(pos[0], pos[1], pos[2])
vth = irfpy.pep.mhddata.t2vth(temp, mass=16.) # in m/s
n *= 1e6 # in /m3
vx *= 1e3; vy *= 1e3; vz *= 1e3 # in m/s
fmaxwell = mkfunc(n, [vx, vy, vz], vth) # maxwell distribution function in physical coord. No mass dependence.
vel = [-np.sin(postheta) * np.cos(posphi), -np.sin(postheta) * np.sin(posphi), np.cos(postheta)]
vveclist, dflux = get_dflux2(fmaxwell, pos, vel, m=m) # O+ assumede.
enelist = ((vveclist / np.sqrt(2 * q / m)) ** 2).sum(0)
#### dflux has (128, 32, 16) dimension.
# panel0: el 24-31 (zenith), az 0-1,14-15 (RAM), max
dfluxall[0, ilat, :] = dflux[:, 24:32, [0, 1, 14, 15]].max(2).max(1)
## Convert to count rate
j2c = irfpy.jdc.flux0.Flux2Count()
c = np.zeros_like(dfluxall)
for ie in range(128):
c[:, :, ie] = j2c.getCounts(dfluxall[:, :, ie], ie)
ax = fig.add_subplot(2, 1, 1)
xax = np.linspace(0, 360, ndiv + 1)
yax = energy.getBound()
x, y = np.meshgrid(xax, yax)
### Plot the data.
img = ax.pcolor(x, y, np.ma.log10(c[0]).T, vmin=np.ma.log10(vmin), vmax=np.ma.log10(vmax))
ax.set_yscale('log')
ax.set_xlim(0, 360)
ax.set_ylim(1, 41000)
fig.colorbar(img)
return pp
if __name__ == "__main__":
pp = main(longitude=0)
plt.savefig('app08_jdc_jna_flyover_1.png')
pp = main(longitude=0, type='nadir')
plt.savefig('app08_jdc_jna_flyover_2.png')