2.3.1
spase://CNES/NumericalData/CDPP-AMDA/PSP/SPC/psp-spc-fit
fits
SWEAP Level 3 fits
2019-11-12T10:48:29Z
This data product contains derived measurements of ion properties in the solar wind, including
density, temperature, velocity vector. The velocity, temperature, and density of the solar wind proton
population are estimated by fitting each spectrum to a single Maxwellian or a set of Maxwellian ion
populations.
* p1
fit to the “primary” proton peak. This is the peak or largest amplitude observed in a
given l2i spectrum. A locus of measurements is selected that includes the absolute
maximum and at least the 1/e folding, if possible, on either side for this fit.
* a
fit to the “primary” alpha particle (He++) peak, if resolved. For l3i measurements, this is
“guessed” by searching for a secondary peak in each l2i spectrum in the neighborhood
of twice the p1 peak energy.
* 3
if an additional high signal-to-noise feature is present in the l2i spectrum, typically due
to a proton beam or shoulder but also potentially due to a cold minor ion population, a fit
is attempted to the p1-subtracted residuals on this neighborhood. The POP3_MTOQ
variable is used to indicate the species.
* p_tot
if p1 and 3 are successfully fit, and the 3 population is determined to be protons, this
signifies the total proton parameters (np =total proton density, vp = center of mass
velocity, wp = effective thermal velocity, accounting for both populations and their relative
drift).
Please acknowledge the NASA Parker Solar Probe Mission and SWEAP team
led by Justin Kasper for use of data.
spase://SMWG/Person/Justin.C.Kasper
PrincipalInvestigator
spase://SMWG/Person/Anthony.W.Case
SPCInstrumentScientist
User Guide
https://spdf.sci.gsfc.nasa.gov/pub/data/psp/sweap/sweap_data_user_guide.pdf
User Guide for Parker Solar Probe SWEAP-SPC Investigation Data Products
spase://SMWG/Repository/CNES/CDPP-AMDA
Online
Open
AMDA at CDPP
http://amda.cdpp.eu
Text
AMDA is a science analysis system provided by the Centre de Donnees de la
Physique des Plasmas (CDPP) supported by CNRS, CNES, Observatoire de Paris and
Universite Paul Sabatier, Toulouse
SPDF
psp/sweap/spc/l3/l3i/
Please acknowledge the CDAWeb team at GSFC/SPDF.
spase://CNES/Instrument/CDPP-AMDA/PSP/SPC
Spectrum
2018-09-02T00:00:12Z
2025-08-12T23:59:55Z
PT0.2S
PT250S
Heliosphere.Inner
Sun.Corona
np1
psp_spc_np1
Number density, fitted to the “primary” proton peak
cm-3
TimeSeries
np1_uncertainty
psp_spc_dnp1
Estimated uncertainty on the number density, fitted to the “primary” proton peak
cm-3
TimeSeries
wp1
psp_spc_wp1
Thermal velocity = sqrt(2kT/m), fitted to the “primary” proton peak
km/s
TimeSeries
wp1_uncertainty
psp_spc_dwp1
Estimated uncertainty on the thermal velocity, fitted to the “primary” proton peak
km/s
TimeSeries
vp1_rtn
psp_spc_vp1
Velocity vector, estimated from the radial thermal velocity fit p1 and flow angle
km/s
TimeSeries
3
vp1r
Component.I
1
psp_spc_vp1(0)
vp1t
Component.J
2
psp_spc_vp1(1)
vp1n
Component.K
3
psp_spc_vp1(2)
vp1_uncertainty
psp_spc_dvp1
Velocity vector component upper uncertainties
km/s
TimeSeries
3
dvp1r
Component.I
1
psp_spc_dvp1(0)
dvp1t
Component.J
2
psp_spc_dvp1(1)
dvp1n
Component.K
3
psp_spc_dvp1(2)
na
psp_spc_na
Number density, fitted to the “primary” alpha particle (He++) peak, if resolved
cm-3
TimeSeries
na_uncertainty
psp_spc_dna
Estimated uncertainty on the number density, fitted to the “primary” alpha particle (He++) peak, if resolved
cm-3
TimeSeries
wa
psp_spc_wa
Thermal velocity = sqrt(2kT/m), fitted to the “primary” alpha particle (He++) peak, if resolved
km/s
TimeSeries
wa_uncertainty
psp_spc_dwa
Estimated uncertainty on the thermal velocity, fitted to the “primary” alpha particle (He++) peak, if resolved
km/s
TimeSeries
va_rtn
psp_spc_va
Velocity vector, estimated from the radial thermal velocity fit and flow angle
km/s
TimeSeries
3
var
Component.I
1
psp_spc_va(0)
vat
Component.J
2
psp_spc_va(1)
van
Component.K
3
psp_spc_va(2)
va_uncertainty
psp_spc_dva
Velocity vector component uncertainties
km/s
TimeSeries
3
dvar
Component.I
1
psp_spc_dva(0)
dvat
Component.J
2
psp_spc_dva(1)
dvan
Component.K
3
psp_spc_dva(2)
n3
psp_spc_n3
Number density, fitted to the p1 substracted residuals
cm-3
TimeSeries
n3_uncertainty
psp_spc_dn3
Estimated uncertainty on the number density, fitted to the p1 substracted residuals
cm-3
TimeSeries
w3
psp_spc_w3
Thermal velocity = sqrt(2kT/m), fitted to the p1 substracted residuals
km/s
TimeSeries
w3_uncertainty
psp_spc_dw3
Estimated uncertainty on the thermal velocity, fitted to the p1 substracted residuals
km/s
TimeSeries
v3_rtn
psp_spc_v3
Velocity vector, estimated from the radial thermal velocity fit and flow angle
km/s
TimeSeries
3
v3r
Component.I
1
psp_spc_v3(0)
v3t
Component.J
2
psp_spc_v3(1)
v3n
Component.K
3
psp_spc_v3(2)
v3_uncertainty
psp_spc_dv3
Velocity vector component uncertainties
km/s
TimeSeries
3
dv3r
Component.I
1
psp_spc_dv3(0)
dv3t
Component.J
2
psp_spc_dv3(1)
dv3n
Component.K
3
psp_spc_dv3(2)
np_tot
psp_spc_np_tot
If p1 and 3 are successfully fitted, total proton density
cm-3
TimeSeries
np_tot_uncertainty
psp_spc_dnp_tot
Estimated uncertainty on the number density
cm-3
TimeSeries
wp_fit
psp_spc_wp_tot
If p1 and 3 are successfully fitted, effective thermal velocity
km/s
TimeSeries
wp_tot_uncertainty
psp_spc_dwp_tot
km/s
Estimated uncertainty on the thermal velocity
TimeSeries
vp_tot_rtn
psp_spc_vp_tot
If p1 and 3 are successfully fitted, center of mass velocity vector
km/s
TimeSeries
3
vp_totr
Component.I
1
psp_spc_vp_tot(0)
vp_tott
Component.J
2
psp_spc_vp_tot(1)
vp_totn
Component.K
3
psp_spc_vp_tot(2)
vp_tot_uncertainty
psp_spc_dvp_tot
Velocity vector component uncertainties
km/s
TimeSeries
3
dvp_totr
Component.I
1
psp_spc_dvp_tot(0)
dvp_tott
Component.J
2
psp_spc_dvp_tot(1)
dvp_totn
Component.K
3
psp_spc_dvp_tot(2)