KCollins
commented
4 days ago Relevant code snippet - got this from Xueling:
mom_vars = pyspedas.mms.mom(probe=[spacecraft_id.lower()], trange=[start.timestamp(), end.timestamp()],
# mom_vars = pyspedas.mms.mom(probe=[spacecraft_id.lower()], trange=[epoch.timestamp()-5*60, epoch.timestamp()+5*60],
notplot=True,no_update=False,time_clip=True)
thx_density = mom_vars['th'+spacecraft_id.lower()+'_peem_density']
thx_density_time = thx_density['x']
thx_density_data = thx_density['y']
#calculate dynamic pressure
thx_peim_velocity = mom_vars['th'+spacecraft_id.lower()+'_peim_velocity_gse']
thx_velocity_data = thx_peim_velocity['y']
thx_velocity_Vx = thx_velocity_data[:,0]
thx_velocity_Vy = thx_velocity_data[:,1]
thx_velocity_Vz = thx_velocity_data[:,2]
print("Computing dynamic pressure for event ", event, " out of ", len(mms_events), ".")
thx_pdy = thx_density_data*(thx_velocity_Vx**2+thx_velocity_Vy**2+thx_velocity_Vz**2)*1.67*(10**(-6))*0.5 # should return nPa
dyp = thx_pdy[~pd.isnull(thx_pdy)] # dynamic pressure vector without NaNs
mms_events.loc[epoch, 'Dynamic Pressure (nPa)'] = dyp.max()
mms_events.loc[epoch, 'Electron density'] = thx_density_data[np.argmax(dyp)]
mms_events.loc[epoch, 'Vx'] = thx_velocity_Vx[np.argmax(dyp)]
mms_events.loc[epoch, 'Vy'] = thx_velocity_Vy[np.argmax(dyp)]
mms_events.loc[epoch, 'Vz'] = thx_velocity_Vz[np.argmax(dyp)]
Validate dynamic pressure calculations.
should be: inst_val - inst_val/(min_before + min_after)