Scrunching

The scrunching of spectra into a (usually) linear wavelength scale provides exactly the same facilities available using the FIGARO SCRUNCH program, except that it works on an order-by-order basis.

See the SCRUNCH documentation for details.

The package provides both global (bin size constant for all orders) and per-order scrunching options. The global option would normally be used when it is necessary to co-add the extracted orders from multiple data frames, and a standard bin-size is required.

Your own linear wavelength scale may be defined by supplying start wavelength and bin size, or the defaults calculated by the program may be used. In addition, there are options available to allow multiple spectra to be scrunched to the same output scale and the results to be merged together.

The scruncher automatically merges multiple orders using the local median intensities as weighting factors. In addition each order may either be scrunched to a global scale (i.e. all orders have the same bin size), or to its own optimal bin size (i.e. that which gives an equal number of bins to the original).

To merge multiple spectra to the same output scale use the ech_mulmrg option/task.