Data Set Information
|
DATA_SET_NAME |
MARS EXPRESS ASPERA-3 CAL RDR ELECTRON SPECTROMTR EXT3 V1.0
|
DATA_SET_ID |
MEX-M-ASPERA3-3-RDR-ELS-EXT3-V1.0
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NSSDC_DATA_SET_ID |
|
DATA_SET_TERSE_DESCRIPTION |
This data set contains calibrated Mars Express ASPERA-3
Electron Spectrometer (ELS) data for the third mission
extension (January 1, 2010 - Dec. 31, 2012). The data
are provided in units of Differential Number Flux (DNF):
cnts/(cm**2-sr-sec-eV)
|
DATA_SET_DESCRIPTION |
Overview:
=========
The Electron Spectrometer (ELS) provides in situ electron
measurements in the energy range 0.05 eV to 20 keV to help
satisfy the following scientific objectives:
1. Determine the instantaneous global distributions of plasma
and neutral gas near Mars by providing undisturbed solar
wind parameters
2. Define the local characteristics of the main plasma regions
3. Complement the ENA images
Parameters:
===========
All ELS data products have the same format and parameters, and
each row (data file record) in the ELS SPREADSHEET data products
has eight (8) COLUMN objects (parameters):
1. Start Time - Begin Date/Time in UTC of data samples
2. Stop Time - Ending Date/Time in UTC of data samples
3. Data Type Name - SENSOR, SCAN, or MODE. The SENSOR rows are
the ELS science data for each sector (16 sectors). The SCAN
rows are the deflection voltages (volts) that correspond to
the SENSOR rows. There is one SCAN row per 16 SENSOR rows.
The 16 SENSOR rows are followed by one corresponding SCAN
row. The SCAN row indicates the deflection voltage per
step that corresponds to the previous 16 SENSOR rows for
each step. To convert the deflection voltages to center
energies (eV), use the K_FACTOR per anode in the
calibration tables: eV = volt * K_FACTOR. There are 16
SENSOR rows + 1 SCAN row (17 in all) followed by 23 rows of
MODE data for the same time period. The MODE rows contain
informational data such as Time/Step Summations and Sector
Enable Flags.
4. Data Type Id - Numeric ID indicating SENSOR, SCAN, or MODE.
5. Data Name - Short description for data on that row. For
example 'ELS Sector 0 LR' for ELS sector 0 Low Range
science data (SENSOR rows for ELSSCIL data products), 'ELS
Sector 0 HR' for ELS sector 0 High Range science data
(SENSOR rows for ELSSCIH data products), 'Deflection
Potential' for SCAN rows, or 'Time Summation' for
informational data (MODE row).
6. Data Unit - Indicates the data unit:
'cnts/(cm**2-sr-sec-eV)' for SENSOR data
'volt' for SCAN data
'Unitless' for MODE data
7. Values - These are the actual data values. For this column
there are multiple values as indicated by the ITEMS keyword
in the label files. This value will vary from file to
file, but remains consistent within a data (.CSV) file.
For the SENSOR rows, these are the science data sampled at
the corresponding deflection volts indicated in the
corresponding SCAN row that follows the 16 ELS sector
(SENSOR rows) data. The MODE data rows contain only one
value each and remaining ITEMS are indicated 'missing' with
commas (value,,...,,). Please note that the data values
are formatted for a high level of accuracy, and that this
does not indicate the accuracy of the ELS instrumentation.
8. Data Quality Value - Quality indicator for the data on that
row. The data quality value is only applicable for the
SENSOR data. See CONFIDENCE_LEVEL_NOTE under 'Data
Coverage/Quality' for valid values and descriptions.
Data Products:
==============
The Standard Data Products for ELS PSA Level 2 (RDR) products
are:
1. ELSSCIL_DNF - ELectron Spectrometer SCIence Low range
data in Differential Number Flux units.
2. ELSSCIH_DNF - ELectron Spectrometer SCIence High range
data in Differential Number Flux units.
NOTE: There is not a one-to-one correspondence between the
ELSSCIL and ELSSCIH data products. Most of the time,
both products are produced for the same time period.
However, there are times when only ELSSCIL products are
produced or only ELSSCIH products are produced, not
both.
Ancillary Data:
===============
It is important for ASPERA-3 science studies to know where in
space and time the Mars Express spacecraft and ASPERA-3
instruments are located and what objects (Sun, Mars, Earth,
Phobos, Deimos) are in the fields of views. The ASPERA-3 view
directions for each sensor can be derived using the SPICE kernels
and software. The ASPERA-3 Sensor Frames and Geometry Information
document (in DOCUMENT directory) provides a code example (in C
and FORTRAN) for determining the view directions for the ASPERA-3
sensors.
Coordinate System:
==================
The ASPERA-3 data are always in the instrument reference frame
since data are sampled in situ. The GEOMETRY table contains
spacecraft related parameters expressed in the J2000 reference
frame, and the ASPERA-3 Sensor Frames and Geometry Information
document (in DOCUMENT directory) provides information for
determining the ASPERA-3 sensors view directions and transforming
to the J2000 reference frame.
References:
===========
Refer to the ASPERA-3 Experiment to Archive Interface Control
Document (EAICD) found in the DOCUMENT directory
(MEX_ASPERA3_PSA_ICD_V01_03) for more information and detail
concerning data set formulation and contents.
|
DATA_SET_RELEASE_DATE |
2011-02-23T00:00:00.000Z
|
START_TIME |
2010-01-01T12:00:00.000Z
|
STOP_TIME |
N/A (ongoing)
|
MISSION_NAME |
MARS EXPRESS
|
MISSION_START_DATE |
1997-10-31T12:00:00.000Z
|
MISSION_STOP_DATE |
N/A (ongoing)
|
TARGET_NAME |
MARS
|
TARGET_TYPE |
PLANET
|
INSTRUMENT_HOST_ID |
MEX
|
INSTRUMENT_NAME |
ANALYZER OF SPACE PLASMA AND ENERGETIC ATOMS (3RD VERSION)
|
INSTRUMENT_ID |
ASPERA-3
|
INSTRUMENT_TYPE |
ENERGETIC PARTICLE DETECTOR
|
NODE_NAME |
Planetary Plasma Interactions
|
ARCHIVE_STATUS |
ARCHIVED - ACCUMULATING
|
CONFIDENCE_LEVEL_NOTE |
Review:
=======
These data have been reviewed by the instrument team and are of
the highest quality that can be generated at this time. Science
results based on these data have been published in several
journals (Science, Nature, EGU, etc.). After submission to the
PDS, these data successfully completed the peer review process.
Data Coverage/Quality:
======================
The data quality indicators in the data files for each sensor are
associated with the data returned in telemetry. Valid values
are:
0 - Good Data: Default because assumption is that data
are good unless determined otherwise.
1 - Questionable Data: +30V monitor value is not within
tolerance
2 - Invalid Data: +12V, -12V, +5V, or -5V monitor value is not
within tolerance or high voltage is not
enabled
3 - Bad Data: +30V monitor value and (+12V, -12V, +5V, or -5V
monitor value) are not within tolerance
4 - Unknown State: Time related Main Unit housekeeping packet
is not available.
-1 - Data Unavailable: No data returned for the sensor, so a
fill value is used for data quality.
Limitations:
============
There are no known limitations at this time.
|
CITATION_DESCRIPTION |
Lundin, R., S. Barabash, D. Winningham, R. Frahm,
MARS EXPRESS ASPERA-3 CAL RDR ELECTRON SPECTROMTR EXT3 V1.0,
MEX-M-ASPERA3-3-RDR-ELS-EXT3-V1.0,
ESA Planetary Science Archive (PSA),
NASA Planetary Data System (PDS), 2005
|
ABSTRACT_TEXT |
This data set contains calibrated Mars Express ASPERA-3
Electron Spectrometer (ELS) data for the third mission
extension (January 1, 2010 - Dec. 31, 2012). These data
are provided in units of Differential Number Flux (DNF):
cnts/(cm**2-sr-sec-eV)
|
PRODUCER_FULL_NAME |
SANDEE JEFFERS
|
SEARCH/ACCESS DATA |
Planetary Plasma Interactions Website
Mars Express Archives at GEO
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