Sherpa Threads
Introduction
Beginners should start here. The Introductory threads explain how to start Sherpa and provide an overview of using the application.
Getting Started:
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Starting Sherpa
![[Updated]](../imgs/updated.gif)
(13 Dec 2012)
- Obtaining data used in Sherpa threads
- Running Scripts in Sherpa
- Utilizing Sherpa's Parallelized Functions
- ChIPS commands, and the ChIPS GUI, are used from within Sherpa to customize plots and create hardcopy output (PS, PNG, JPG). Refer to the Introduction to ChIPS thread for an overview of using that program.
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Starting Sherpa
- Introduction to Fitting ASCII Data with Errors: Single-Component Source Models
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Introduction to Fitting PHA Spectra
(13 Dec 2012)
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."
Spectral (1-D) Data
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Introduction to Fitting PHA Spectra
(13 Dec 2012)
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Changing the grouping scheme of a data set within Sherpa
(13 Dec 2012)
- Introduction to Fitting ASCII Data with Errors: Single-Component Source Models
- Simultaneously Fitting Two Data Sets
- Fitting a PHA Data Set with Multiple Responses
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Simulating X-ray Spectral Data (PHA): the fake_pha command
(13 Dec 2012)
- Simulating Chandra ACIS-S Spectra with Sherpa
- Simulating Chandra ACIS-S LETG Spectra with Sherpa
- Simulating IXO/CAT Spectra with Sherpa
- Simulating NuSTAR X-Ray Spectra with Sherpa
- Fitting PHA Data with Multi-Component Source Models
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Calculating Uncertainties by Simulating Flux Distributions
(13 Dec 2012)
- Simultaneously Fitting Source and Background Spectra
- Using A Pileup Model
- Sherpa User Models
- Sherpa Table Models
- Sherpa Template Models
- Creating an Input Spectrum for MARX and ChaRT Simulations
- Bayesian Analysis in Sherpa
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Introduction to Fitting PHA Spectra
Spatial (2-D) Data
- Fitting FITS Image Data
- Radial and elliptical profiles of Image Data
- Using an Exposure Map in Fitting Image Data
- Accounting for PSF Effects in 2D Image Fitting
- Fitting Image Data with Convolved and Unconvolved Model Components
- See also: the Obtain and Fit a Radial Profile CIAO thread
- Sherpa User Models
Grating Data
Users interested in conducting wavelength analysis are encouraged to learn the limitations associated with the set_analysis command before doing so with the information contained in these threads.
Generic Data
These threads involve data analysis which is not specific to X-ray spectral or spatial modeling, therefore they can be followed using simple ASCII files as input, or other non-X-ray data.
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.
![[New]](../imgs/new.gif)
(13 Dec 2012)
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.
-
Simulating X-ray Spectral Data (PHA): the fake_pha command
(13 Dec 2012)
- Simulating Chandra ACIS-S Spectra with Sherpa
- Simulating Chandra ACIS-S LETG Spectra with Sherpa
- Simulating IXO/CAT Spectra with Sherpa
- Creating an Input Spectrum for MARX and ChaRT Simulations
- Simulating NuSTAR X-Ray Spectra with Sherpa
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.
![[Sherpa Logo]](../imgs/sherpa_logo_navbar.gif){kind=logo}
