Sherpa Threads
All threads
A list of all the threads on one page.
Introduction
Beginners should start here. The Introductory threads explain how to start Sherpa and provide an overview of using the application.
Scripts
To quickly access the scripts used in each of the Sherpa threads, visit the Sherpa Quick Scripts page.
Fitting
Sherpa provides extensive facilities for modeling and fitting data. The topics here range from basic fits using source spectra and responses to more advanced areas, such as simultaneous fits to multiple data sets, accounting for the effects of pileup, and fitting spatial and grating data.
Before fitting ACIS spectral data sets with limited pulse-height ranges, please read the CIAO caveat "Spectral analyses of ACIS data with a limited pulse-height range."
Plotting
Sherpa allows the user to plot data, fits, statistics, ARFs, contours, and more. These threads describe the basics of plotting as well as various methods for customizing plots.
Statistics
Sherpa provides numerous tools for determining goodness of fit, errors in parameter values, confidence intervals, and other statistical measures of a model's validity. These threads describe how to use these tools in your analysis.
Simulations
The Sherpa fake_pha command is available for simulating a Chandra PHA data set with an input instrument response and source model expression. These threads describe how to produce simulated data appropriate for your analysis.
Miscellaneous
These threads demonstrate miscellaneous tasks in Sherpa which you may find useful in your scientific analysis, and which are not specific to the other thread categories.