NAME gtalphabkg - Computes relative contributions to likelihood weights from different analysis components USAGE gtalphabkg inputs outfile epsilon DESCRIPTION This tool is used to estimate the contributions to likelihood weights when combining different analysis components. This estimate is defined likelihood will be de-weighted so as to give an uncertainty estimate that is a fraction (epsilon) of the effective background. PARAMETERS inputs [filename] A text file that consists of a list of FITS files with the effective background for the various components of the analysis. outfile [filename] Name of the output FITS file that will contain the generated factor needed to set the likelihood weights correctly. epsilon [float] Epsilon parameter, this is the fractional systematic uncertainty, i.e., the desired systematic uncertainty, expressed as a fraction of the effective background. Defaults to 0.03. (chatter) [integer] This parameter fixes the output verbosity: no screen output (0), nominal screen output (2), maximum verbosity (4). Default is "2". (clobber) [boolean] If true, an existing file of the same name will be overwritten. Default is "yes". (debug) [boolean] Activate debugging mode. Default is "no". When debug is "no", all exceptions that are not caught and handled by individual tool-specific code are caught by a top-level exception handler that displays information about the exception and then exits. When debug is "yes", such exceptions are not caught by the top level code. Instead the tool produces a segmentation violation, which is more useful for debugging. When debugging mode is enabled, the tool produces more verbose output describing any errors or exceptions that are encountered. (gui) [boolean] Graphical User Interface (GUI) mode is activated if set to "yes". Default is "no". (mode) [string] Mode of automatic parameters: "h" for batch, "ql" for interactive. Default is "ql". EXAMPLES Parameters are passed following the FTOOLs model: They could be passed answering from a prompt, as a list in a command line, or by editing the parameter file. To run gtalphabkg simply type in the command line: > gtalphabkg The parameter values have to be provided. Not all parameter are prompted: some of them are "hidden". To change one of the "hidden" parameter, the user should specify the values in the command line or modify its mode by editing the parameter file. For example, to avoid overwriting the outfile, the following command line has to be typed: > gtalphabkg clobber=no An example of how to run the tool is given below: > gtalphabkg Text file with list of input files[] bkgeff_list.txt Output File[] alphabkg.fits Epsilon parameter, fractional syst. uncertainty[0.03] That last example could be also run in the command line as follows: > gtalphabkg inputs=bkgeff_list.txt outfile=alphabkg.fits epsilon=0.03 SEE ALSO gtlike gtsrcmaps gtltcube gteffbkg gtwtsmap