- @map_gpd_csf (.mopsic is default extension)
- Pipeline for reduction of OTF maps. Very general 3-level cascade CSF applied (Correlated Signal Filter, i.e. the filtering of the sky noise; cascade = uses the results from the previous level). Alternatively to the 3-level CSF a source model can be supplied as a single- beam or a double-beam map. For the latter case a special model for each map would be used analogous to the automatically calculated db-source model, which is stored in the backup buffer (command store) within this pipeline. Such model can be used directly within the CSF or (a better solution) subtracted before and add back after the CSF. Unfortunately, this method can't be controlled by a single variable, requires therefore significant custom changes of the pipeline. WARNING: the CRUTIAL condition for correct data processing of OTF double-beam maps is the
- MAP SIZE along the SCANNING COORDINATE
- source_size_above_the_noise + beam_separation + base_range + array_size (base_range = MAX(3*HPBW,0.5*source_size_above_the_noise),
- array_size ~ 245" for MAMBO2)
- In such case ALL basic reduction steps (base line corrections, CSF, EKH) will create or remove emission ! NOTES:
- All variables affecting the data reduction are defined and set in map_defs.mopsic. You can modify them there or (the suggested method) create a custom reduction script (i.e. a clone of map_gpd_csf.mopsic) and overwrite them in this script (as e.g. in map_gpd_csf0.mopsic, map_gpd_csfdsrmx.mopsic, map_gpd_csfrmn_saa.mopsic, map_gpd_ncsf.mopsic).
- - can still remove the peaks of stronger sources - disable the removal of weaker spikes
- of the CSF in order to calculate the compact sources (i.e. smaller than the array_size) with the highest possible S/N and subtract them before the CSF; this allows to optimize the parameters for calculation of more
extended sources, i.e. > 3*HPBW, in the 3rd cascade of the CSF; the optimal results can be obtained only if a polygon around the source is defined (meq=yes, pol_meq and proj_meq defined); Also important for extracting of compact sources for the cascade CSF (i.e. csflevel=2 & 3): [mask] within -#level or within #level_neg #level_pos which masks the pixels with signal within the given intensity range => leaves the db-source outside the given range
- CSF cascade) it might be better to use either csflevel=0 (i.e. no cascade CSF and the source calculation optimized for extended sources) or a source model (weaksou=yes and define sbsource);
5) for weak compact sources use csflevel=1 & SAA (i.e. shiftandadd, the final
reduction requires a model & SAA)
- See also the remarks given in the help for CSF (? csf). Source model for double-beam data within the CSF: source your_model.fits sb if it is a double-beam distribution source your_model.fits db if it is a single-beam distribution (other formats are also accepted, e.g. GDF) Subtracting and adding the signals calculated using the model outside the CSF: define sbsource -(+) horizontal_data your_model.fits if it is a double-beam distribution -(+) db_data your_model.fits if it is a single-beam distribution (double-beam data are ALWAYS calculated in horizontal system) To optimize, choose the appropriate:
< #low [rms] > #hig [rms] [base range ...] base in time # [base in subscans #] ! base lines row-by-row in the maps require base
- range ! might be very dangerous !
< #low_csf [rms][not_in_data] > #high_csf [rms][not_in_data] range #min #max best # if source calculation disabled ALWAYS:
- cn median
- cn average or cn median ?