Introduction

Xselect is a command line interface to the Ftools, for X-ray astrophysical analysis. It has four major functions,

• to organize the input of data through the observation catalogue ( see the OBSCAT section for a summary ), and store it internally for easy use ( see FILES ).
• to enter region, timing and pha filters ( see FILTER ), which can be applied to the data.
• to make selections based on the Housekeeping and auxillary filter files ( see SELECT ).
• to extract images, light curves and spectra from the data ( see EXTRACT ).

In addition, there are routines to plot up various aspects of the data, and the HK and auxillary filter files ( see PLOT ).

There are also routines of importance for specific missions. Currently, the sisclean and faint commands are the only examples, but more will accrue as time goes on. In the near future, commands for analysing the ASCA SIS faint mode, and GIS MPC mode data, and for doing GIS background subtraction.

There are also general utility commands ( see ADMIN ) to save the products of the analysis, to clear various selections, data choices, etc.

We also describe the command line interpreter used by Xselect: XPI. It allows scripting, aliasing, spawning, and command recall. It also has a few pecularities which must be attended to.

Then, under the Commands subheading, we list all the Xselect commands available.

Each Xselect session is given a session prefix, which is prepended to the names of the product files. In the rest of this manual, we will use the default session name: xsel.

 
• OBSCAT
• FILES
• FILTER
• SELECT
• EXTRACT
• PLOT
• ADMIN