| DATA_SET_DESCRIPTION |
Data Set Overview
=================
The Thermal Evolved Gas Analyzer (TEGA) is designed to analyze
~50 mg of fine grained Martian soil or rock fragments. TEGA
consists of four basic components: a soil delivery system,
an oven/calorimeter thermal analyzer (TA), a gas storage and
handling system, and a mass spectrometer acting as an
evolved-gas analyzer (EGA). A full description of the TEGA
instrument can be found in [BOYNTONETAL2008].
The data set PHX MARS THERMAL EVOLVED GAS ANALYZER 1 EDR
is a time series collection of TA, EGA, engineering, and
commanding measurements from the TEGA aboard the Mars Phoenix
Lander. Data types included in this data set
are engineering data, calorimeter data from the TA,sweep mode
EGA data, mass hopping mode EGA data, LED oven fill data, and
instrument message log data. Data are sorted by time, with each
data file containing one measurement day's worth of data from
midnight to midnight UTC.
TEGA is designed to analyze 8 individual samples, one sample in
each of the eight single use ovens. The EGA portion of the
instrument will not only analyze the gases evolved from the
samples heated in the ovens, but will also analyzed samples of
the Martian atmosphere. TEGA is expected to operate for 45 days.
During operations the science, engineering and housekeeping data
are downloaded from the spacecraft by the Jet Propulsion
Laboratory (JPL) into the Telemetry Data System(TDS). The
TDS sends data to a process that translates data packets and
examines instrument health via messages. Data are output to a
spooler that passes them to the University of Arizona (UA)
database ingest process. The ingest process inputs raw data
into the UA database. Data are retrieved from the UA database
to build the TEGA EDR data products.
The TEGA EDR data set is intended to be the lowest level
(level 0) data available for TEGA. It should be useful to those
scientists who are experienced in calorimetry and mass
spectrometry.
Parameters
==========
The TEGA EDR data set is composed of three main data types and
three supporting data types. The objective of compiling the
TEGA EDR is to create a record of the primary data collected by
TEGA. The following paragraphs discuss the parameters of
interest in each of the data types.
SC DATA
-----
The SC data are time series records taken over the course
of a measurement day. Data files are labeled with the date.
Individual records are a single data collection interval. SC
data are the science data produced by the TA.
EGA DATA
--------
The EGA data are time series records taken over the course of
a measurement day. Data files are labeled with the date.
Individual records are a single data collection interval.
EGA data are the science data produced by the EGA mass
spectrometer in sweep mode.
EGH DATA
--------
The EGH data are time series records taken over the course of
a measurement day. Data files are labeled with the date.
Individual records are a single data collection interval. EGH
data are the science data produced by the EGA mass
spectrometer in mass hopping mode.
The Engineering, LED fill and Message Log, data sets provide
supporting information.
Engineering Data
----------------
The Engineering data are time series records for each
engineering parameter taken over the course of a measurement
day. Data files are grouped in the ENG folder and are labeled
with the engineering parameter name. Individual records are a
single data collection interval that is variable in duration.
Engineering values are reported by parameter name and include
collection time, and DN value. Engineering values are
specific monitor values recorded by TEGA.
Message Log
-----------
The Message Log data are time series records taken over the
course of a day. Data files are labeled with the date.
Individual records are a single data collection interval. The
Message Log data are messages returned from TEGA.
LED
---
LED data are time series records taken over the course
of a measurement day. Data files are labeled with the date.
Individual records are a single data collection interval,
which is variable in duration. The LED data are the data
collected by the oven fill sensors, and indicate when an oven
is full of sample material.
Processing
==========
TEGA data (both science and engineering) are downloaded from
the Phoenix Mars Lander by JPL into the Telemetry Data System
(TDS). The TDS sends the data to a process called TEGA_tl, that
translates GRS packets from any source to any destination and
examines instrument health via messages. The data are checked
for packet types, header information, messages, or errors.
Data are output to a spooler, which passes data to the UA
database ingestion process. The ingestion process inputs raw
telemetry data into the database.
A function reads the data header to get the total number of
bytes in the packet, and the sequence bytes. The rest of the
packet is then read. The data type, read from the common header,
is returned, determining the next step in the processing. One
of a number of different procedures is run to insert packet
data into the appropriate database tables. If the data type
returned is less than or equal to 0 an error message is
returned stating that the packet was not inserted. Once all
data packets for a measurement day are ingested into the
database, the EDR data products are created by reformatting
the raw data in accordance with the data formats specified
by the product labels.
Data
====
The TEGA EDR data set is composed of a series of date stamped
files that contain 1 day's worth (24 hours, 00:00:00 UTC to
23:59:59 UTC) of data for 6 different data types. The following
sections describe each data type.
SC DATA
-------
SC data are composed of raw scanning calorimeter data. These
data include start and end time of collection, oven and shield
power, and associated current, potential, and pulse data.
EGA DATA
--------
EGA mass spectrometer data is composed of start and stop times
of the collection, scan type, voltage, emission energy and
counts at each of four collectors.
EGH DATA
--------
EGH data are mass hopping mode EGA data. These data include
start and stop times for the collection, voltage, emission
energy and level, and counts at the detector.
Engineering Data
----------------
Engineering data are composed of the 85 different engineering
readings monitored in TEGA. The engineering readings can be
taken at several different time intervals. The following is a
list of all the engineering readings and a description of
each.
TA_MANIFOLD_PRES Manifold Pressure
TA_PLUS_5_VREF +5V REF
TA_OUTLET_PRES Outlet Pressure
TA_MANIFOLD_TEMP TA Manifold Temperature
TA_EGA_PLUMB_TEMP MS Plumbing Temperature
TA_EGA_BAKEOUT_TEMP Bakeout temperature
TA_PLUMBING_1_TEMP Plumbing 1 Temperature
TA_PLUMBING_2_TEMP Plumbing 2 Temperature
TA_EGA_MAN_TEMP MS Manifold Temperature
TA_CAL_TANK_TEMP Cal Tank Temperature
TA_CPU_TEMP CPU Temperature
TA_PWR_SPLY_1_TEMP Power Supply 1 Temperature
TA_PWR_SPLY_2_TEMP Power Supply 2 Temperature
TA_PWR_CNTL_1_TEMP Power Control 1 Temperature
TA_PWR_CNTL_2_TEMP Power Control 2 Temperature
TA_A2D_TEMP ADC Temperature
TA_COVER_1_TEMP cover 1 temperature
TA_INPUT_FUNNEL_1_LO_TEMP Funnel 1 Temperature
TA_PRES_SENSE_FD_BK Pres Sense Exc. Feedback
TA_INPUT_FUNNEL_2_LO_TEMP Funnel 2 Temperature
TA_OVEN_TEMP Oven Temperature
TA_SHLD_TEMP Shield Temperature
TA_EGA_ELECT_BOX_TEMP TEB Temperature
TA_T_HEATER_TEMP 'T' Heater Temperature
TA_TRANS_TUBE_TEMP Transfer Tube Temperature
TA_EGA_GEC_TEMP GEC Temperature
TA_BUS_A_VOLT Bus A Voltage
TA_AGD_0_1 AGD_0_3 ground
TA_AGD_3_1 AGD_3_1 ground
TA_CPU_PLUS_5_VOLT CPU Voltage
TA_ANLG_PLUS_12_VOLT Analog +12V Voltage
TA_ANLG_MINUS_12_VOLT Analog -12V Voltage
TA_OVEN_PLUS_15_VOLT Oven Voltage
TA_SHIELD_PLUS_30_VOLT Shield Voltage
TA_BUS_A_CUR Bus A Current
TA_BUS_B_CUR Bus B Current
TA_EGA_CUR EGA Current
TA_CPU_PLUS_5_CUR CPU Current
TA_ANLG_PLUS_12_CUR Analog +12V Current
TA_ANLG_MINUS_12_CUR Analog -12V Current
TA_OVEN_PLUS_15_CUR Oven Current
TA_SHIELD_PLUS_30_CUR Shield Current
TA_FULL_DETECT Full Detect Integrated
TA_FULL_DETECT_RAW Full Detect Raw
TA_OVEN_ERR Oven Error
TA_SHLD_ERR Shield Error
TA_CAL_TANK_COLD_TEMP Cal Tank Cold Temperature
TA_COVER_2_TEMP cover 2 Temperature
MEM_OVEN_INT_LO Oven integrator val lo bytes
MEM_OVEN_INT_HI Oven integrator val hi bytes
MEM_SHLD_INT_LO Shield integrator val lo bytes
MEM_SHLD_INT_HI Shield integrator val hi bytes
MEM_OVEN_VOLT Oven voltage
MEM_OVEN_CUR Oven current
MEM_SHLD_VOLT Shield voltage
MEM_SHLD_CUR Shield current
MEM_MANIFOLD_PRES Manifold pressure
MEM_OVEN_ERR Oven error
MEM_SHLD_ERR Shield error
MEM_T_WIDTH T pulse width
COVER1_DONE Cover1 Limit Switch
COVER2_DONE Cover2 Limit Switch
MEM_OVEN_WIDTH Oven pulse width
MEM_SHLD_WIDTH Shield pulse width
EGA_STATUS_BITS Status bits value
EGA_TRAP_CUR Trap current monitor
EGA_EMISSION_CUR Emission current monitor
EGA_FILAMENT_1 Filament 1 in use
EGA_FILAMENT_2 Filament 2 in use
EGA_PLUS_5_VOLT +5 volt monitor
EGA_PLUS_12_VOLT +12 volt monitor
EGA_MINUS_12_VOLT -12 volt monitor
EGA_FILAMENT_CUR_1 Filament 1 current monitor
EGA_FILAMENT_CUR_2 Filament 2 current monitor
EGA_MULTIPLIER_VOLT Multiplier voltage monitor
EGA_ION_PUMP_VOLT Ion Pump voltage monitor
EGA_ION_PUMP_CUR Ion Pump Current monitor
EGA_SWEEP_VOLT Sweep voltage monitor
EGA_GEC_CUR GEC current monitor
EGA_MAGNET_TEMP_1 Magnet 1 temperature
EGA_MAGNET_TEMP_2 Magnet 2 temperature
EGA_PROC_TEMP CPU temperature
EGA_AVG_CALLS Average # calls to Task Queue
EGA_MIN_CALLS Minimum # calls to Task Queue
EGA_SPARE_3 Spare
EGA_SPARE_4 Spare
Message Log
-----------
The Message Log data consists of the data sent from the
TEGA electronics in response to some action taking place
in the instrument. The message data includes
general messages and warnings as well as error messages.
LED DATA
--------
The LED data consists of the time of the LED reading and
the state of the sensor. This data is used to indicate
when an oven is full of sample.
Ancillary Data
==============
Ancillary data are listed by data type.
Message Log
-----------
A list of all message ID's and their associated meanings can
be found in the Message Log label file. A list of message
detail ID's and the associated information can be found in the
tega_message_dict document located in the document directory.
Coordinate System
=================
Several coordinate systems are used by the Phoenix project. A
detailed description can be found in the TEGA EDR SIS document
found in the Documents directory.
Software
========
No TEGA specific software is provided with this data set.
PDS-labeled images and tables can be viewed with the program
NASAView, developed by the PDS and available for a variety of
computer platforms from the PDS web site
http://pds.nasa.gov/tools/software_download.cfm. There is no
charge for NASAView.
Media/Format
============
The TEGA EDR will be delivered using DVD media. Formats will be
based on standards for such products established by the
Planetary Data System (PDS) [PDSSR2001].
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