Diff for "CookbookMopsic"

To run MOPSIC from all directories on your system you furthermore need to add to the same file the path where the MOPSIC executable is located:

Of course it is not mandatory to keep MOPSIC and the DAFs in the directories created by the tar. You may put them wherever you want.

MOPSIC pipeline scripts

defs_general.mopsic script: The database pipeline reduction scripts are developed such that they can easily be used for data reduction on your local PC. To do so, you have to edit the script. Simply change the logicalforiramdbto false:

let foriramdb .false.   ! or let foriramdb no

This will set the input data directory and the default input list to the directory structure generated by the tar file and all DAFs to defaults, i.e. to the entries defined by MOPSIC_DAFS.

The main routines used for the data reduction are oo_csf.mopsic and map_gpd_csf.mopsic

MOPSIC uses a special method to calculate the chopped signal. This gives much better results than the straight difference of the signals obtained at both chopper positions. The method is described in the Dec. 2005 IRAM Newsletter. For some special purposes also special scripts are offered. They are obtained simply by changing some default variables set in map_defs and/or oo_defs correspondingly.

Mapping

• map_gpd_ncsf.mopsic : (gridded phase difference - no correlated signal filter) map reduction without sky noise subtraction

• map_gpd_csf.mopsic : (gridded phase difference - correlated signal filter general script formap reduction with sky noise subtraction

• map_gpd_csfdsrmx.mopsic : special scripts to reduce maps of relatively compact sources, <200" in diameter; it is not suitable for more extended and structureless sources but should give better sky noise subtraction for relatively compact sources.

• map_gpd_csf0.mopsic : map reduction with sky noise subtraction for sources which are weak (for CSF) and more extended than 0.5*beam_separation; weak for CSF means with peak fluxes < ~5*rms in the final data of one bolometer (i.e. ~5*30 mJy/beam)

• map_gpd_csfrmn_saa.mopsic :(gridded phase difference - correlated signal filter - shift and add) source structure is assumed to be smaller than 0.5*beam_sep.

OnOff

• oo_ncsf.mopsic (onoff - no correlated signal filter) reduces onoffs without sky noise subtraction

• oo_csf.mopsic (onoff - correlated signal filter) reduces onoffs with sky noise subtraction

Both on-off scripts write the final results to 'source'.OOxx files. For solar system sources ("body") the corresponding scripts oo_ncsf_body and oo_csf_body are also within the tar. Note that the only one change between the "body" and the standard on-off scripts is the additional argument body within the oo-command.

There is also a script oo_csf_csfr_multsou.mopsic whic allows to reduce on-offs of many sources. The user has to define the number of sources and the lists with the files. Those can be created from a general lis using the commad find objects write.

Misc

In addition there are also scripts to reduce pointings (p_nshav.mopsic - without sky noise subtraction, p_shav.mopsic - with very simple sky noise subtraction), skydips (skydips.mopsic) and to calculate the RCPs (Receiver Channel Parameters) from calibration maps. T

he scripts in the subdir specials are special versions of the general pipeline scripts. They use some other settings than defined in map_defs (see the corresponding map_defs_*). They are therefore optimized for some special purposes (e.g. subtracting a source distribution before reduction, applying base level corrections subscan by subscan, using polygons to define the base range, ...).

In the subdir extras you will find some scripts useful for checking (e.g. chk_rc) or just displaying the data. The snr... scripts demonstrate how to calculate a signa-to-noise ratio map.

In the subdir simple you will find a script map.mopsic which can be used to reduce maps of simple sources, e.g. compact or extended. It should not be used if the source shows both compact and extended components !

To start MOPSIC type mopsic. Macros are called with @scriptname WEAKSOU (no extension needed). The argument WEAKSOU may have values no or yes and allows to optimise the data processing for weak sources, i.e. sources with peak flux densities below ~50mJy/beam in case of on-offs or ~200mJy/beam in case of maps. If you are using the default download structure you can reduce your data straight forward by calling your preferred script, e.g:

@map_gpd_csf WEAKSOU

or

@oo_csf WEAKSOU

MOPSIC will read all observations from the mydata.LIST, select the corresponding type of observations (i.e. maps or on-offs) and display a list of these selected observations. Within the reduction scripts you have different possibilities to select the data you may want to process:

select name          ! select all observations of a specific source (combined result)
select name*         ! select similar source names (e.g. to create a mosaic of maps or on-offs done on different parts of a source)
select no name[*]    ! excludes observations from the LIST with defined source names (do not use the exclude command, it is not finished)

To have a help online just type:

? select or ? delete  !lists all possibilities

The command find objects [> #, write] might also help.

Typing c will continue the reduction. The final result will be written to a FITS file in case of mapping. The default output name is scriptname.fits. Note that MOPSIC will not overwrite any results obtained in a previous reduction, except for GDF-files. If you use the same script for a different source make sure you move the FITS file to a different name before starting the script again or - the better solution - create dedicated scripts for each source and change the default fits name. IF YOU DO NOT CARE OVERWRITING the prevoius results, use the GDF files as output.

To view the results on a graphic device, open the device (before or after you execute the script:

device image white (or black)
lut idl4  ! Choose color table

for maps:

plot [options] , e.g. plo scaling linear -30 100

for onoffs:

plot oo [options].

There are also some pl... scripts, which might help checking the data quality.

Since MOPSIC is under developement and still not fully integrated within the GILDAS software, no detailed manual is available so far. A help on individual commands, however, is available by typing: ? command or help command for GILDAS commands.

Almost all commands used for advanced data reduction can be found in the MOPSIC scripts. MOPSIC, however, offers a much broader range of applications including advanced planning functions for mapping and onoff observations, post-reduction data analysis and processing and even reduction of non-bolometer data (optical, IR, spectroscopy). If you have questions how to obtain the best results from your data do not hesitate to contact Robert Zylka ( zylka@iram.fr ).

Appendix

Notes for maps

Look at NoteMopsicMaps for some detailed explanation on the settings of the reduction.

Notes for OnOff

Look at NoteMopsicOnoff for some detailed explanation on the settings of the reduction