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XMM-Newton Guest Observer Facility


The GOF has streamlined the time-honored ABC Guide to make it easier to find and use the sections that users may be interested in, taking into account what type of data they have, where they want to reduce them (on a local machine with their own version of SAS, or over the internet with SAS in Web Hera), and how they want to reduce them: on a command line, or with a GUI that shows all the task keywords. Users who are new to SAS will likely prefer the GUI (or, for Hera, the Parameter Window), while more experienced users may prefer the command line (or, for Hera, the command window). The walk-throughs use the same example datasets as in the ABC Guide, and are listed below. All are publicly available through the HEASARC archive.

All of the run-throughs assume that the data has been downloaded to either your local machine or the Hera server and uncompressed.

If you are reducing data locally, is also assumed that SAS has already been installed and initialized. Information on setting up SAS and running it can be found here.

An introduction to the Hera interface and a short description of how it works is here.

New users are reminded that SAS does not come with fitting software, so you will need to fit your data with CIAO or HEAsoft packages.

And now we can reduce our data!

SAS in Hera is returning! Thank you for your patience while we shake out the bugs.

Updated for XMM-SAS 18.0

Data Type Example Dataset Locally-Installed SAS SAS in Hera
EPIC (IMAGING Mode) Lockman Hole, ObsID 0123700101 Command Line or GUI Command Window
EPIC-PN (TIMING Mode) Cen X-3, ObsID 0400550201 Command Line or GUI Command Window
EPIC-MOS (TIMING Mode) Mkn 841, ObsID 0070740101 Command Line or GUI Command Window
RGS Capella, ObsID 0134720401 Command Line or GUI Command Window
OM (IMAGE mode) Lockman Hole, ObsID 0123700101 Command Line or GUI Command Window
OM (FAST mode) Mkn 421, ObsID 0411081601 Command Line or GUI Command Window
OM (GRISM mode) BPM 16274, ObsID 0125320801 Command Line or GUI Command Window

SAS does not include fitting software for further data analysis, but there are several commonly-used packages that can used for this purpose. Links to how to fit EPIC and RGS spectra with some of them are below. Prior to fitting, users are strongly encouraged to read this Guide's discussion on statistics. More information can be found in Nousek & Shue (1989), Humphrey et al. (2009), Kaastra (2017), and the discussion on statistics (Chapter 7) in The Handbook of X-ray Astronomy.

I want to... Example Dataset Locally-Installed Software Software in Hera
Fit an EPIC Spectrum with Sherpa Lockman Hole, ObsID 0123700101 Command Line
Fit an RGS Spectrum with Xspec Capella, ObsID 0134720401 Command Line

If you have any questions concerning XMM-Newton send e-mail to

This file was last modified on Tuesday, 18-Jun-2019 11:29:57 EDT
Curator:Michael Arida (ADNET);

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