Guide to Swift data processing and analysis
Swift software
GSFC's getting started guide
Leicester's XRT help page
Build XRT products for any source
Jump to Data Analysis.
Software
The pipeline processing of the Swift Data is performed at the Swift Data Center (SDC) at the Goddard Space Flight Center (GSFC). Data received from the spacecraft, via telemetry dumps to the Malindi Ground Station, (Level 0 files) are used to create FITS files containing image and event data from from the 3 instruments. These files are then sent through the pipeline, which leads to the formation of calibrated images, cleaned event lists and light-curves/spectra for the GRB afterglow candidate (where possible).
The image below shows a flow diagram indicating the different levels of Swift data processing. The raw telemetry is converted to Level 1 FITS files, which then undergo a small amount of processing. Level 2 calibrated event lists and sky images are produced after data screening and coordinate transformation. The Level 2 products then go through the scripts for each instrument, leading to spectra, light-curves and combined sky images (Level 3 files).
These products are then placed on the Quick Look
data area, from where they will be available to the GRB community. After a
week, the data will be archived by the data centres in the UK and Italy and by HEASARC (in the USA).
The Swift analysis software is part of HEASoft (the High Energy Astrophysics Software), which encompasses FTOOLS and XANADU (i.e., XSPEC, XRONOS and XIMAGE for spectral, timing and image analysis respectively). A list of some of the Swift tools can be found here. They can also be listed using the FTOOLS command fhelp swift.
The Swift Technical Handbook provides an overview of the mission, instruments, operations and data.
Software Guides
BAT Software Users' Guide (PDF file)
XRT Software Users' Guide (PDF file)
UVOT Software Users' Guide (PDF file)
The following buttons point to introductory walk-through data analysis guides written
locally, but based on the "official" (much longer!) software guides. They
cover each step of the different instrument scripts, to allow the user to
process the data and products. Much more detail can be found in
the software guides listed above.
Assuming all the data from one observation is saved in one master directory, there will be many subdirectories under the main sw[obsid].[segid] (e.g. 00020521001.004 is a typical name for the master directory). The segment ID - 004 in this example - indicates how many times the data have been through the pipeline. The Swift Observation Definition document explains the system for assigning Observation IDs in detail, but a brief overview is given here.
|
UK Swift Science Data Centre
Last updated 2010 March 12
Web page maintained by Kim Page ()
|
| 
