Radio Fitting: HCN example with freely varying hyperfine amplitudes =================================================================== .. include:: Example hyperfine line fitting for the HCN 1-0 line. .. literalinclude:: ../examples/hcn_example.py :language: python The green lines in the following figures all show the residuals to the fit .. figure:: images/hcn_fixedhf_fit.png :alt: Fit to the 3 hyperfine components of HCN 1-0 simultaneously with fixed amplitudes. The (0)'s indicate that this is the 0'th velocity component being fit (though that velocity corresponds to the 12-01 component of the line) :figwidth: 650 :width: 650 Fit to the 3 hyperfine components of HCN 1-0 simultaneously with fixed amplitudes. The (0)'s indicate that this is the 0'th velocity component being fit (though that velocity corresponds to the 12-01 component of the line) .. figure:: images/hcn_freehf_fit.png :alt: Fit to the 3 hyperfine components of HCN 1-0 simultaneously with freely varying amplitudes. The (0)'s indicate that this is the 0'th velocity component being fit :figwidth: 650 :width: 650 Fit to the 3 hyperfine components of HCN 1-0 simultaneously with freely varying amplitudes. The (0)'s indicate that this is the 0'th velocity component being fit .. figure:: images/hcn_freehf_ampandwidth_fit.png :alt: Fit to the 3 hyperfine components of HCN 1-0 simultaneously. The widths are allowed to vary in this example. :figwidth: 650 :width: 650 Fit to the 3 hyperfine components of HCN 1-0 simultaneously. The widths are allowed to vary in this example. .. figure:: images/hcn_fixedhf_fit_2components.png :alt: Two-component fit with amplitude & width fixed. :figwidth: 650 :width: 650 A two-component fit to the same spectrum. It appears to be a much better fit, hinting that there are indeed two components (though the fit is probably not unique)