• This exercise, along with Part II on Monday, will roughly follow the analysis outlined on these web pages. We will use both the RXTE (PCA & HEXTE) data discussed on those pages, as well as the main script (.isisrc*) files found on those pages.
• The script files are in a compressed, tar file (isisrc.tar.gz) which can be obtained directly from here. Unpack these files into your home directory, and edit the path variable found in the main .isisrc file proper.  Note:  these files are required for a number of the exercises (today, Monday, and the Timing Exercises on Wednesday).   Thus you'll find links to this tar file in a few places.  There's only one set of files, so you only need to download these once.  (The Timing Exercises require additional downloads.)
• The data for the above exercise can be downloaded directly from the gzipped, tar file (data.tar.gz), found here.
• Here is the PDF outlining this practice exercise.

XSPEC Practice Exercise

• This exercise will make use of a set of spectra from BeppoSAX observations of the black hole candidate Cyg X-1. A link to the gzipped, tar file (cygx1_hard_.tar.gz) is found here.
• The PDF describing the practice exercise is found here.

TESTING YOUR SOFTWARE SETUP

•  Assuming that you've installed HEASOFT and ISIS and the ISIS scripts according to the install instructions, and you have downloaded the data above, do the following to test your setup.
• Unpack the data in a working directory, e.g., ~/TEST, go to this directory, and do the following commands (C-shell version shown - modify as necessary for other shells, and set path names to the appropriate ones for your setup)

prompt%> setenv HEADAS /usr/local/src/heasoft-6.9/i386-apple-darwin10.4.0/

prompt%> source $HEADAS/headas-init.csh

prompt%> xspec

You will now see something like what shown below. The following are xspec commands.  When prompted for a response, just enter blank returns:

                XSPEC version: 12.6.0
        Build Date/Time: Tue Jun 22 11:56:06 2010

XSPEC12> cpd /xs

XSPEC12> data pca.pha

(... various output ...)

XSPEC12> model powerlaw

(... a couple of blank returns required, followed by output ...)

XSPEC12> query y

XSPEC12> fit

XSPEC12> plot ld del

• If you see data plot with residuals, congratulations, you have a working version of XSPEC!  (Don't worry that the fit at this point is absolutely terrible.  The goal is to make sure that the program works.)
• Now, let's test ISIS.  Unpack the isisrc.tar.gz file in your home directory. 
• Edit the .isisrc file, and change the line:

static variable path="/Users/mnowak/";

• Edit the line to correspond to your home directory.
• cd back to the directory with the data, e.g., ~/TEST
• Running the unix which command on isis, should give you something like:

prompt%> which isis

/usr/local/bin/isis

• If you don't have that, then you haven't placed /usr/local/bin in your path, or you haven't downloaded ISIS yet.  Do one or both.  Assuming that you have, then do:

prompt%> isis

Welcome to ISIS Version 1.6.0-16
Copyright (C) 1998-2010 Massachusetts Institute of Technology

          Isis web page: http://space.mit.edu/cxc/isis/
   Mailing list archive: http://space.mit.edu/cxc/isis/archive/
 Send questions to the mailing list: .
     For a summary of recent changes, type:  "help changes"

isis> load_data("pca.pha");

RMF includes the effective area
1
isis> fit_fun("powerlaw");
isis> fit_counts;
 Parameters[Variable] = 2[2]
            Data bins = 129
           Chi-square = 8131.856
   Reduced chi-square = 64.03036
0
isis> rplot_counts(1);
isis> plot_counts(1;res=2);
isis> exit;

• If the above produced a couple of plots, then congratulations, you have a working version of ISIS and are good to go!