Data Description

This page summarizes information about the selected resource and its origin based on SPASE metadata.

Table of Contents

  1. Product
  2. Repositories
  3. Instrument
  4. Observatory
  5. Persons

SPASE version 2.0.0

Numerical Data Product: Geotail Editor-A 12 second Low-Energy Particles

Resource ID
spase://Example/NumericalData/Geotail/LEP/EDA.PT12S
Name
Geotail Editor-A 12 second Low-Energy Particles
Description

An example subset of the 12-second Editor-A low-energy particle data from the Geotail spacecraft.

Editor-A data are only acquired with the real-time operation in Usuda Deep Space Center (UDSC),Japan, while the Editor-B data are 24-hours continuouslyrecorded in the onboard tape recorders and are dumpedover the NASA/JPL Deep Space Network (DSN) stations.

The ion energy analyzer (LEP-EAi) has two energy scan mode: RAM-A (60 eV to 40 keV) and RAM-B (5 keV to 40 keV). RAM-B is selected to protect the very sensitive detector from intense low energy fluxes that are usually seen in the solar wind and magnetosheath. The energy scan mode is automatically selected onboard depending on incoming ion fluxes. At present, only the ion moments in the RAM-A mode are listed for the LEP-EAi data.

The ion moment data of the solar wind analyzer (LEP-SW) should be used only qualitatively. The LEP-SW ion moments are listed when the energy scan mode of LEP-EAi is RAM-B.

Additional information
The Geotail Low Energy Particle Experiment (LEP)

Reprint of Mukai, T., S. Machida, Y. Saito, M. Hirahara, T. Terasawa, N. Kaya, T. Obara, M. Ejiri, and A. Nishida, The low energy particle (LEP) experiment onboard the Geotail satellite, J. Geomag. Geoelectr., 46, 669-692, 1994.

Acknowledgement

In any publications, the use of the Geotail data should be acknowledged, for example, as "Geotail magnetic field data were provided by Y. Saito, JAXA in Japan."

Contact
Role Person
1. Principal investigator Dr. Yoshifumi Saito
2. Scientist Dr. Donald H. Fairfield
3. Metadata contact Jan Merka
Release date
2009-05-20 23:06:12
Repository #1
Name
CDAWeb Data Repository FTP Interface
Availability
Online
Access rights
Open
URL
CDAWeb FTP download
Encoding
None
Acknowledgement

Data provider Y. Saito at JAXA, Japan and CDAWeb.

Repository #2
Name
Data ARchives and Transmission System (DARTS)
Availability
Online
Access rights
Open
URL
DARTS/Geotail

Data ARchives and Transmission System (DARTS) is a versatile space science data archive for astrophysics, solar physics, and solar-terrestrial physics. DARTS primarily consists of the data acquired by Japanese scientific satellites and spacecrafts. DARTS is developed and maintained by the Center of Science-satellite Operation and Data Archive (C-SODA) at ISAS/JAXA.

Encoding
ASCII
Acknowledgement

In any publications, the use of the Geotail data should be acknowledged, for example, as "Geotail magnetic field data were provided by Y. Saito through DARTS at Institute of Space and Astronautical Science, JAXA in Japan."

Instrument
Geotail Low Energy Particle Experiment
Measurement type
Thermal plasma
Temporal description
Start date
2004-01-01 00:00:00
Stop date
2005-01-01 00:00:00
Cadence
12 seconds
Observed regions
Earth.Magnetosheath
Earth.Magnetosphere
Earth.Magnetosphere.Magnetotail
Heliosphere.NearEarth
Caveats

Please use the Editor-A LEP dataset prior to the Editor-B LEP dataset since plasma moments in the Editor-A data are more reliable. (Plasma moments inthe Editor-B are calculated onboard.)

The ion moment data of the solar wind analyzer (LEP-SW) should be used only qualitatively.

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Parameters

Parameter #1

Name
Time Line
Parameter key
Epoch
Description

Number of milliseconds since the CDF epoch

Units
ms
Conversion to SI units
1e-3>s
Valid minimum
12-Nov-1994 00:00:00.000
Valid maximum
31-Dec-2020 00:00:00.000
Fill value
-1.0E31
Parameter type
Temporal

Parameter #2

Name
Ion density
Parameter key
Ni
Description

Ion density

Caveats

Qualitative use only if Energy Scan Code = 2, i.e. if the energy scan mode is RAM-B/SW.

Units
cm^-3
Conversion to SI units
1e-6>m-3
Valid minimum
0.0
Fill value
-1.0E31
Particle type
Proton
AlphaParticle
Ion
Quantity
Number density
Energy range
Low energy
60
High energy
38150
Units
eV

Parameter #3

Name
Ion temperature
Parameter key
T
Description

Ion temperature in satellite coordinates

Caveats

Qualitative use only if Energy Scan Code = 2, i.e. if the energy scan mode is RAM-B/SW.

Units
eV
Coordinate system
Cartesian SC
Structure
Size
2
Elements
Index Name Valid min Valid max Fill value
1 Ti,yy -10 10000 -1.0E31
2 Ti,zz -10 10000 -1.0E31
Particle type
Proton
AlphaParticle
Ion
Quantity
Temperature
Energy range
Low energy
60
High energy
38150
Units
eV

Parameter #4

Name
Sensor
Parameter key
Sensor
Description

Name of the instrument sensor measuring data.

Fill value
-1.0E31
Parameter type
Other

Parameter #5

Name
Mode
Parameter key
scan_code
Description

Energy scan code/mode:

  • 1 = sensor EA = energy scan mode RAM-A
  • 2 = sensor SW = energy scan mode RAM-B
Valid minimum
1
Valid maximum
2
Parameter type
Other

Parameter #6

Name
Ion velocity (GSE)
Parameter key
VGSE
Description

Ion velocity in GSE coordinates

Caveats

Qualitative use only if Energy Scan Code = 2, i.e. if the energy scan mode is RAM-B/SW.

Units
km/s
Conversion to SI units
1e3>m/s
Coordinate system
Cartesian GSE
Structure
Size
3
Elements
Index Name Component Valid min Valid max Fill value
1 Vxi (GSE) I -2000 2000 -1.0E31
2 Vyi (GSE) J -2000 2000 -1.0E31
3 Vzi (GSE) K -2000 2000 -1.0E31
Particle type
Proton
AlphaParticle
Ion
Quantity
Flow velocity
Energy range
Low energy
60
High energy
38150
Units
eV

Parameter #7

Name
Geotail position (GSE)
Parameter key
XYZGSE
Description

Geotail position in GSE cartesian coordinates

Caveats

1 Re = 6371.2 km

Units
Re
Conversion to SI units
6.3712e6>m
Coordinate system
Cartesian GSE
Structure
Size
3
Elements
Index Name Component Valid min Valid max Fill value
1 X (GSE) I -500.0 500.0 -1.0E31
2 Y (GSE) J -500.0 500.0 -1.0E31
3 Z (GSE) K -500.0 500.0 -1.0E31
Parameter type
Positional
Qualifier
Vector

Parameter #8

Name
Ion velocity (GSM)
Parameter key
VGSM
Description

Ion velocity in GSM coordinates

Caveats

Qualitative use only if Energy Scan Code = 2, i.e. if the energy scan mode is RAM-B/SW.

Units
km/s
Conversion to SI units
1e3>m/s
Coordinate system
Cartesian GSM
Structure
Size
3
Elements
Index Name Component Valid min Valid max Fill value
1 Vxi (GSM) I -2000 2000 -1.0E31
2 Vyi (GSM) J -2000 2000 -1.0E31
3 Vzi (GSM) K -2000 2000 -1.0E31
Particle type
Proton
AlphaParticle
Ion
Quantity
Flow velocity
Energy range
Low energy
60
High energy
38150
Units
eV

Parameter #9

Name
Geotail position (GSM)
Parameter key
XYZGSM
Description

Geotail position in GSM cartesian coordinates

Caveats

1 Re = 6371.2 km

Units
Re
Conversion to SI units
6.3712e6>m
Coordinate system
Cartesian GSM
Structure
Size
3
Elements
Index Name Component Valid min Valid max Fill value
1 X (GSM) I -500.0 500.0 -1.0E31
2 Y (GSM) J -500.0 500.0 -1.0E31
3 Z (GSM) K -500.0 500.0 -1.0E31
Parameter type
Positional
Qualifier
Vector

Parameter #10

Name
Ion velocity (SM)
Parameter key
VSM
Description

Ion velocity in SM coordinates

Caveats

Qualitative use only if Energy Scan Code = 2, i.e. if the energy scan mode is RAM-B/SW.

Units
km/s
Conversion to SI units
1e3>m/s
Coordinate system
Cartesian SM
Structure
Size
3
Elements
Index Name Component Valid min Valid max Fill value
1 Vxi (SM) I -2000 2000 -1.0E31
2 Vyi (SM) J -2000 2000 -1.0E31
3 Vzi (SM) K -2000 2000 -1.0E31
Particle type
Proton
AlphaParticle
Ion
Quantity
Flow velocity
Energy range
Low energy
60
High energy
38150
Units
eV

Parameter #11

Name
Geotail position (SM)
Parameter key
XYZSM
Description

Geotail position in SM cartesian coordinates

Caveats

1 Re = 6371.2 km

Units
Re
Conversion to SI units
6.3712e6>m
Coordinate system
Cartesian SM
Structure
Size
3
Elements
Index Name Component Valid min Valid max Fill value
1 X (SM) I -500.0 500.0 -1.0E31
2 Y (SM) J -500.0 500.0 -1.0E31
3 Z (SM) K -500.0 500.0 -1.0E31
Parameter type
Positional
Qualifier
Vector
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SPASE version 2.0.0

Instrument: Geotail Low Energy Particle Experiment

Instrument ID
spase://Example/Instrument/Geotail/LEP
Name
Geotail Low Energy Particle Experiment
Alternate name
Geotail LEP
Description

The low energy particle (LEP) instrument onboard Geotail is designed to make comprehensive observations of plasma and energetic electrons and ions with fine temporal resolution in the terrestrial magnetosphere (mainly magnetotail) and in the interplanetary medium. It consists of three units of sensors (LEP-EA, LEP-SW and LEP-MS) and common electronics (LEP-E).

The Energy-per-charge Analyzers (EA) measure three-dimensional velocity distributions of electrons (with EA-e) and ions (with EA-i) simultaneously and separately, over the energy-per-charge of several eV/q to 43 keV/q. Emphasis in the EA design is laid on the large geometrical factor to measure tenuous plasma in the magnetotail with sufficient counting statistics in the high-time-resolution measurement.

On the other hand, the Solar Wind ion analyzer (SW) has smaller geometrical factor, but fine angular and energy resolutions, to measrue energy-per-charge spectra of the solar wind ions. In both EA and SW sensors, the complete three-dimensional velocity distributions can only be obtained in a period of four spins, while the velocity moments up to the third order are calculated onboard every spin period (nominally, 3 sec).

The energetic-ion Mass Spectrometer (MS) failed shortly after launch and no data are available.

Additional information
The Geotail Low Energy Particle Experiment (LEP)

Reprint of Mukai, T., S. Machida, Y. Saito, M. Hirahara, T. Terasawa, N. Kaya, T. Obara, M. Ejiri, and A. Nishida, The low energy particle (LEP) experiment onboard the Geotail satellite, J. Geomag. Geoelectr., 46, 669-692, 1994.

Acknowledgement

In any publications, the use of the Geotail LEP data should be acknowledged, for example, as "Geotail magnetic field data were provided by Y. Saito, JAXA in Japan."

Contact
Role Person
1. Principal investigator Dr. Yoshifumi Saito
2. Scientist Dr. Donald H. Fairfield
3. Metadata contact Jan Merka
Release date
2009-05-20 21:10:15
Instrument type
Mass Spectrometer
Quadrispherical Analyser
Investigation name
Geotail Low Energy Particle experiment
Observatory
Geotail
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SPASE version 2.0.0

Observatory: Geotail

Observatory ID
spase://Example/Observatory/Geotail
Name
Geotail
Alternate name
1992-044A
GTL
ISTP/Geotail
GGS/Geotail
Geomagnetic Tail Lab
Description

The solar wind draws the Earth's magnetic field into a long tail on the nightside of the Earth and stores energy in the stretched field lines of the magnetotail. During active periods, the tail couples with the near-Earth magnetosphere, sometimes releasing energy stored in the tail and activating auroras in the polar ionosphere.

The Geotail mission measures global energy flow and transformation in the magnetotail to increase understanding of fundamental magnetospheric processes. This includes the physics of the magnetopause magnetospheric boundary regions, the lobe and plasma sheet, and reconnection and neutral line formation, i.e., the mechanisms processes of input, transport, storage, release and conversion of mass, momentum and energy in the magnetotail.

Geotail, together with Wind, Polar, SOHO, and Cluster projects, constitute a cooperative scientific satellite project designated the International Solar Terrestrial Physics (ISTP) program which aims at gaining improved understanding of the physics of solar-terrestrial relations.

Geotail is a spin-stabilized spacecraft utilizing mechanically despun antennas with a design lifetime of about four years. The nominal spin rate of the spacecraft is about 20 rpm around a spin axis maintained between 85-89 degrees to the ecliptic plane. Geotail is cylindrical, approximately 2.2 m in diameter, and 1.6 m high. with It has body-mounted solar cells. Geotail also has and a back-up battery subsystem which that operates when the spacecraft is in the Earth's shadow (limited to 2 hrs). Real-time telemetry data transmitted in X-band are received at the Usuda Deep Space Center (UDSC) in Japan. There are two tape recorders on board, each with a capacity of 450 Mb, which allows daily 24-hour data coverage and are collected in playback mode by the NASA Deep Space Network (DSN).

The Geotail mission is divided into two phases. During the two-year initial phase, the orbit apogee was kept on the nightside of the Earth by using the Moon's gravity in a series of double-lunar swing-by maneuvers that result in the spacecraft spending most of its time in the distant magnetotail (maximum apogee about 200 Earth radii) with a period varying from one to four months. Then, in November 1994, there were a series of maneuvers that reduced the apogee to 50 Re. After three more months in the magnetotail the spacecraft was put in a 10 by 30 Re orbit where it has remained except that the perigee was reduced from 10 to 9 Re in June 1997.

Details on the Geotail mission and instrumentation are given in the Journal of Geomagnetism and Geoelectricity (Vol. 46, No. 1, 1994); online from JGG at

http://www.terrapub.co.jp/journals/EPS/JGG

Additional information
NSSDC's Master Catalog

Information about the Geotail mission

Contact
Role Person
1. Project scientist Guan Le
2. Project scientist Prof. Masaki Fujimoto
3. Metadata contact Jan Merka
Release date
2009-05-20 20:00:12
Location
Region
Earth.Magnetosphere
Heliosphere.NearEarth
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SPASE version 2.0.0

Person: Dr. Yoshifumi Saito

Name
Dr. Yoshifumi Saito
Organization
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
Address
3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan
Email
saito@stp.isas.jaxa.jp
Fax number
+81-42-759-8456
Person ID
spase://Example/Person/Yoshifumi.Saito
Release date
2009-03-18 17:47:02
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SPASE version 2.0.0

Person: Dr. Donald H. Fairfield

Name
Dr. Donald H. Fairfield
Organization
GSFC-Code 695
Email
u2dhf@lepdhf.gsfc.nasa.gov
Phone
+1-301-286-7472
Person ID
spase://Example/Person/Donald.H.Fairfield
Release date
1999-08-18 00:00:00
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SPASE version 2.0.0

Person: Jan Merka

Name
Jan Merka
Organization
NASA Goddard Space Flight Center
Address
Code 672, Greenbelt, MD 20771, USA
Email
jan.merka@nasa.gov
Phone
1-301-286-8751
Person ID
spase://Example/Person/Jan.Merka
Release date
2007-08-09 22:02:24
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SPASE version 2.0.0

Person: Dr. Robert E. McGuire

Name
Dr. Robert E. McGuire
Organization
NASA Goddard Space Flight Center
Address
Code 672, Greenbelt, MD 20771, USA
Email
mcguire@mail630.gsfc.nasa.gov
Phone
1-301-286-7794
Person ID
spase://Example/Person/Robert.E.McGuire
Release date
2007-05-30 15:25:24
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SPASE version 2.0.0

Person: Guan Le

Name
Guan Le
Organization
NASA Goddard Space Flight Center
Address
Code 674, Greenbelt, MD 20771, USA
Email
guan.le@nasa.gov
Phone
+1-301-286-1087
Person ID
spase://Example/Person/Guan.Le
Release date
2007-08-28 20:26:51
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SPASE version 2.0.0

Person: Prof. Masaki Fujimoto

Name
Prof. Masaki Fujimoto
Organization
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency
Address
3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510, Japan
Email
fujimoto@stp.isas.jaxa.jp
Fax number
+81-42-759-8456
Person ID
spase://Example/Person/Masaki.Fujimoto
Release date
2009-03-23 19:02:01
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SPASE version 1.2.0

Repository: CDAWeb Data Repository FTP Interface

Repository ID
spase://Example/Repository/NASA/GSFC/SPDF/CDAWeb
Name
CDAWeb Data Repository FTP Interface
Description

Coordinated Data Analysis Web (CDAWeb) supports not only interactive plotting of variables from multiple instruments on multiple investigations simultaneously on arbitrary, user-defined time-scales. It also supports data retrieval in various formats using its interactive web interface or ftp service.

Additional information
CDAWeb Home Page

Coordinated Data Analysis Web (CDAWeb) home page at Space Physics Data Facility of the NASA Goddard Space Flight Center.

Contact
Role Person
1. Project scientist Dr. Robert E. McGuire
Release date
2008-08-26 21:14:34
Prior ID
spase://Example/Repository/CDAWeb
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SPASE version 1.3.4

Repository: Data ARchives and Transmission System (DARTS)

Repository ID
spase://Example/Repository/DARTS
Name
Data ARchives and Transmission System (DARTS)
Description

Data ARchives and Transmission System (DARTS) is a versatile space science data archive for astrophysics, solar physics, and solar-terrestrial physics. DARTS primarily consists of the data acquired by Japanese scientific satellites and spacecrafts. DARTS is developed and maintained by the Center of Science-satellite Operation and Data Archive (C-SODA) at ISAS/JAXA.

Additional information
DARTS at ISAS/JAXA

DARTS front page.

Contact
Role Person
1. Metadata contact Jan Merka
Release date
2009-03-16 22:47:09
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