Version:2.4.1
NumericalData
ResourceID
spase://CNES/NumericalData/CDPP-AMDA/ACE/SWEPAM/ace-swe-all
ResourceHeader
ResourceName
ACE - SWEPAM - sw : final
AlternateName
Solar Wind 64-Second Level 2 Data
ReleaseDate
2024-09-08 22:04:12Z
Description
Solar Wind Ion parameters from ACE/SWEPAM. Level 2 data, 64-second averages (from AC_H0_SWE dataset). Parameters include proton density,
temperature (radial component) and flow speed, flow velocity vector in GSE and GSM coordinates, and alpha
to proton density ratio.
AMDA presents temperature in eV. The ram pressure is calculated using P=rho*Np*Vp², where rho=1.672622*(1+4*(1/(1-He++_ratio)-1)).
We use rho=2 here, which corresponds to a ratio of He++ between 4% and 5%.
Acknowledgement
Please acknowledge the ACE/SWEPAM instrument team and the ACE Science Center
Contacts
InformationURL
Name
ACE SWEPAM Level 2 data Home Page
URL
Description
ACE Science Center site hosting instrument information, data release notes, as well as web utilities for plotting and downloading data
InformationURL
Name
Rules of use, and caveats
URL
Description
ACE level 2 data rules of use, and caveats
AccessInformation
RepositoryID
Availability
Online
AccessRights
Open
AccessURL
Name
CDPP/AMDA HAPI Server
URL
Style
HAPI
ProductKey
ace-swe-all
Description
Web Service to this product using the HAPI interface.
Format
CSV
Acknowledgement
Thank you for acknowledging the use of AMDA in publications with wording like "Data analysis was performed with the AMDA science analysis system provided by the Centre de Données de la Physique des Plasmas (CDPP) supported by CNRS, CNES, Observatoire de Paris and Université Paul Sabatier, Toulouse". See the Rules of the road at https://amda.cdpp.eu/help/policy.html . Please acknowledge the Data Providers.
AccessInformation
RepositoryID
Availability
Online
AccessRights
Open
AccessURL
Name
CDPP/AMDA Web application
URL
Description
Access to Data via CDPP/AMDA Web application.
Format
CSV
Format
VOTable
Format
CDF
Format
PNG
Acknowledgement
Thank you for acknowledging the use of AMDA in publications with wording like "Data analysis was performed with the AMDA science analysis system provided by the Centre de Données de la Physique des Plasmas (CDPP) supported by CNRS, CNES, Observatoire de Paris and Université Paul Sabatier, Toulouse". See the Rules of the road at https://amda.cdpp.eu/help/policy.html . Please acknowledge the Data Providers.
ProviderName
CDAWeb
ProviderResourceName
ac_h0_swe
InstrumentIDs
MeasurementType
ThermalPlasma
TemporalDescription
TimeSpan
StartDate
1998-02-04 00:00:31Z
StopDate
2024-05-17 23:59:22Z
Cadence
PT64S
ObservedRegion
Heliosphere
ObservedRegion
Heliosphere.NearEarth
Caveats
The quality of ACE level 2 data is such that it is suitable for serious scientific study. However, to avoid confusion and misunderstanding, it is recommended that users consult with the appropriate ACE team members before publishing work derived from the data. The ACE team has worked hard to ensure that the level 2 data are free from errors, but the team cannot accept responsibility for erroneous data, or for misunderstandings about how the data may be used. This is especially true if the appropriate ACE team members are not consulted before publication. At the very least, preprints should be forwarded to the ACE team before publication.
The SWEPAM observations, in particular the proton density and to lesser extent the temperature, became increasing sparse starting in 2010 as the primary channel electron multiplier (CEM) detectors have aged. Now, many years past the original planned mission lifetime, these Ulysses spare detectors do not provide adequate gain to make good measurements. In response, the ACE science team has developed and implemented, starting Oct 23 2012, an innovative mission operations concept that more frequently repoints the ACE spacecraft's spin axis further away from the Sun. This allows other, stronger CEMs that have received significantly less total fluence to measure the solar wind; this operational improvement has significantly increased the frequency of good quality SWEPAM observations, back to levels not seen in several years.
Parameter #1
Name
v_gse
ParameterKey
sw_v_gse
UCD
phys.veloc;phys.atmol.ionStage
Units
km/s
RenderingHints
Structure
Size
3
Element
Name
vx
Index
1
ParameterKey
sw_v_gse(0)
Element
Name
vy
Index
2
ParameterKey
sw_v_gse(1)
Element
Name
vz
Index
3
ParameterKey
sw_v_gse(2)
Particle
ParticleType
Proton
ParticleQuantity
Velocity
Parameter #2
Name
v_gsm
ParameterKey
sw_v_gsm
UCD
phys.veloc;phys.atmol.ionStage
Units
km/s
RenderingHints
Structure
Size
3
Element
Name
vx
Index
1
ParameterKey
sw_v_gsm(0)
Element
Name
vy
Index
2
ParameterKey
sw_v_gsm(1)
Element
Name
vz
Index
3
ParameterKey
sw_v_gsm(2)
Particle
ParticleType
Proton
ParticleQuantity
Velocity
Parameter #3
Name
density
ParameterKey
sw_n
Description
Solar Wind Proton Number Density, scalar
UCD
phys.density;phys.atmol.ionStage
Caveats
Np is the proton number density in units of cm-3, as calculated by integrating the ion distribution function.
Units
cm^-3
RenderingHints
ValidMin
0.0
ValidMax
200.0
FillValue
-1.0E31
Particle
ParticleType
Proton
Qualifier
Moment
ParticleQuantity
NumberDensity
Parameter #4
Name
v_bulk
ParameterKey
sw_vb
Description
Solar Wind Bulk Speed
UCD
phys.veloc;phys.atmol.ionStage
Caveats
Vp is the solar wind proton speed, or more generally just the solar wind (bulk) speed. It is obtained by integrating the ion (proton) distribution function.
Units
km/s
RenderingHints
ValidMin
0.0
ValidMax
2500.0
FillValue
-1.0E31
Particle
ParticleType
Proton
Qualifier
Moment
Qualifier
Scalar
ParticleQuantity
Velocity
Parameter #5
Name
t_radial
ParameterKey
sw_t
Description
radial component of the proton temperature
UCD
phys.temperature;phys.atmol.ionStage
Caveats
The radial component of the proton temperature is the (1,1) component of the temperature tensor, along the radial direction. It is obtained by integration of the ion (proton) distribution function.
Units
eV
RenderingHints
ValidMin
1000.0
ValidMax
1100000.0
FillValue
-1.0E31
Particle
ParticleType
Proton
Qualifier
Moment
ParticleQuantity
Temperature
Parameter #6
Name
alpha/proton ratio
ParameterKey
sw_he
Description
alpha to proton density ratio
UCD
phys.density;arith.ratio;phys.atmol.ionStage
Caveats
Alpha ratio (Na/Np) - is the ratio of the number density of helium++ ions to the number density of protons.
RenderingHints
ValidMin
0.0
ValidMax
10.0
FillValue
-1.0E31
Particle
ParticleType
AlphaParticle
ParticleType
Proton
Qualifier
Ratio
ParticleQuantity
NumberDensity
Parameter #7
Name
ram pressure
ParameterKey
sw_pdyn
Description
P = 2*10e-6 * Np * Vp^2
UCD
phys.pressure;phys.atmol.ionStage
Units
nPa
RenderingHints
Particle
ParticleType
Proton
ParticleQuantity
Pressure