![]() ![]() perform source detection on EPIC fields, via the source detection task edetect_chain.generate Good Time Interval (GTI) files, applicable to later data screening for the optimization of scientific product extraction, based on housekeeping ( hkgtigen) or scientific ( tabgtigen) light curves.visualize the XMM-Newton calibration files, through the GUI-driven calview.manipulate XMM-Newton data files, through the capabilities offered by the Data Access Layer library.browse the content of your ODF, through the GUI-based odfbrowser.SAS is very useful for you if you want to: estimate the amount of pile-up affecting your favorite source in an EPIC field-of-view, through the epatplot task.generate EPIC exposure maps, through the eexpmap task.generate the instrument spectral transfer functions ("response matrices" in the X-ray astronomy jargon) to perform quantitative spectral analysis of X-ray cameras data, via the arfgen plus rmfgen, and rgsrmfgen tasks for EPIC and RGS, respectively.Data screening criteria can be applied "on-the-fly", using the powerful capabilities of the selectlib library evselect is able to extract spectra, images and pseudo-images, light curves, histograms and filtered event lists. The scientific product extractor in the SAS realm is evselect, whith its GUI interface xmmselect. create scientific products according to your own taste and (data screening) criteria.create, maintain or update your set of XMM-Newton calibration data, or build a Calibration Index File (CIF), via the SAS task cifbuild.OM: the SAS reduction pipelines omichain and omfchain (applicable to Image and Fast Mode windows, respectively) generate flat-fielded, and geometrically distortion corrected sky images, source lists and time series light curves.RGS: the SAS reduction pipeline, rgsproc generates, alongside with calibrated and concatenated event lists, background-subtracted spectra and response matrices corresponding to a given sky coordinate or source in an EPIC source list.Similarly, emchain and epchain mirror the PPS SSC pipeline (a comparison between the chain and the proc tasks is discussed here). EPIC: epproc and emproc produce calibrated and concatenated ( i.e.: 1 single file including events from all the detector chips) event lists for the EPIC cameras. ![]() ![]() A set of "reduction metatasks" is available in the SAS to transform the ODF into different levels of scientific products, directly usable for science analysis: In extreme summary, you absolutely need the SAS if you want to: "Bird's eye" view of the SAS capabilities On the other hand, SAS does not include tools for spectral, timing or image analysis (although being able to generate all files - spectra, light curve, response matrices, exposure maps - which are required for the scientific analysis). SAS includes a powerful and extensive suite of FITS file manipulation packages, based on the Data Access Layer library. However, you do not need to know the FTOOLS/LHEASOFT package to work with XMM-Newton data. They provide therefore full compatibility with the most commonly used analysis packages, such as: FTOOLS (FITS file manipulation), XANADU (timing and spectral analysis), SPEX (spectral analysis) SAOIMAGE, SAOTNG, DS9 (image display and analysis). When appropriate, data files produced by the SAS tasks ( e.g.: images, spectra, time series) have been designed to be OGIP-compliant. so all my FTOOLS/LHEASOFT or SPEX knowledge is not useful?ĭon't jump too early to this pessimistic conclusion! Whenever relevant, XMM-Newton data files are FITS (or compressed FITS). This step is advisable, whenever substantial changes in the software and/or instrument calibrations occurred from the time when the ODF were processed by the SSC. Moreover, SAS allows the users to reproduce the reduction pipelines run to get the PPS products (or, at least, a substantial part of them) from the ODFs files. Pipeline Processing System (PPS) products, a collection of validated, top-level scientific products including event and source lists, multiwavelength images and cross-correlation products, generated at the Survey Science Center (SSC).Įven if one starts the analysis of an XMM-Newton datasets with the PPS products, the SAS is necessary to extract standard (spectra, light curves) and/or customized science products. ![]() They contain un-calibrated quantities on a chip-by-chip or science window basis for the X-ray cameras and Optical Monitor, respectively XMM-Newton data are available in two formats: The Science Analysis System ( SAS) is a collection of tasks, scripts and libraries, specifically designed to reduce and analyze data collected by the XMM-Newton observatory. ![]()
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