Make gaussian decomposition easier to run

Setting defaults for the gaussian decomposition. See the examples for specifics.

The best beam parameters to run the gaussian decomposition are:

    interpolate_kernel=1
    beam_gaussian_decomp=1
    beam_gauss_param_transfer = 1
    psf_image_resolution=10.
    beam_mask_threshold=1e6
    save_beam_metadata_only=1
    beam_clip_floor=0
    beam_nfreq_avg=1
    conserve_memory=1e9

This is the best balance between feasible run times and low systematics. Along with these keywords:

    cal_bp_transfer=0
    cal_time_average=0
    auto_ratio_calibration=1
    calibration_catalog_file_path=filepath('GLEAM_EGC_v2_181MHz.sav',root=rootdir('FHD'),subdir='catalog_data')
    cal_stop=1

this will generate the best calibration solutions from FHD for EoR science. This requires 70Gb of memory due to the extent of the beam.

Once calibration solutions have been generated, power spectra can be made using the gaussian beam to lower systematics even more. Change the beam keyword beam_gauss_param_transfer to 'gauss', and set the keywords below:

    restrict_hpx_inds='EoR0_high_healpix_inds_3x.idlsave'
    ps_kspan=200.
    transfer_calibration = <filepath>/calibration/'+obs_id+'_cal.sav'

This requires 40Gb.

EoRImaging / FHD

Make gaussian decomposition easier to run #294