Using FTOOLS and Fv for

Next, we will obtain the plot of a spectrum. Start by closing all of the Fv windows. Then, in your BASH window, type: fhisto region1.fits 3c273_spectrum.fits energy 10 lowval=100 highval=10000 (This represents your input file, output file, keyword, number of channels binned and the energy range in electron volts (eV) , respectively.) ................
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