NASA/Marshall BATSE GRAD STUDENT RESEARCH:OPS PAGE: <headline here>

DAILY OPERATIONS AT BATSE

MISSION OPERATIONS

Mission operations (MOPS) is the backbone of BATSE. Without MOPS, scientific analysis would not be possible. MOPS includes everything from the retrieval of the data from the satellite to the archiving of data for future use. MOPS actually begins at the satellite. BATSE sends a relatively continuous stream of data first to the Tracking and Data Relay Satellite System (TDRSS) which, in turn, transmits the data to ground stations, then the data is sent to the Packet Processing Data Capture Facility (PACOR II). PACOR II accumulates 24 continuous hours of data before forwarding it on to the BATSE MOPS in Huntsville. When the data is received in Huntsville, it has already been filtered once by PACOR II for telemetry errors and gaps, but the data is still in raw format. The raw data is processed by converting it to a readable form, and separating it into several categories. These categories include housekeeping data, trigger data, and other non-trigger scientific data. Housekeeping data includes information used in monitoring the overall performance of the instrument. For example, housekeeping data includes temperatures, voltages, detector gains, etc. Trigger data includes the scientific information taken while the instrument is in trigger mode. This is explained in more detail in the trigger operations section. Non-trigger science data consists of the full day all sky observations done by all eight detectors. From this, transient source information is extracted. MOPS is also responsible for the archiving and the distribution of the categorized data.

Trigger Operations

When two or more of BATSE's eight large area detectors detect at least a 5.5 sigma increase in the counting rates, the instrument goes into trigger mode. While in trigger mode, the detectors increase their data output to include higher resolution data as well as data with different energy binning. These data types are used to make high resolution time profiles of the triggered event, and to compute the event's location. BATSE triggers on several different kinds of events. These events include gamma ray bursts (GRBs), solar flares, soft gamma repeaters (SGRs), terrestrial gamma flashes (TGFs), magnetospheric events, and transient sources. In rare cases, some events are unable to be classified. After the triggers have been processed, they are presented to other BATSE team members for review at the daily BATSE trigger meeting. If there is a disagreement regarding the classification of the trigger, then further analysis is performed until an agreement is reached.

Another part of trigger operations is the newly implemented Rapid Burst Response (RBR) Team. This group receives real time trigger information through the BACODINE network allowing for rapid classification and localization of events. RBR team members are not allowed to do normal trigger operations for the same bursts as to avoid biases. The rapid burst response program has received very positive feedback from the community and is helping to make counterpart observations a reality.

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Author: Georgia Richardson
Curator: Bryan Walls
NASA Official: Frank Six