Preprocessing functionality

Raw file header fixing

The header fixes are controlled via apero.core.core.drs_file.fix_header() which in turn uses the PseudoConst method HEADER_FIXES(). This is defined for each instrument (e.g. apero.core.instruments.spirou.pseduo_const.HEADER_FIXES())

For SPIRou the current header fixes are as follows:

  • clean object name (via apero.core.instruments.spirou.pseduo_const.clean_obj_name())

  • get target type (via apero.core.instruments.spirou.pseduo_const.get_trg_type())

  • get mid observation time (via apero.core.instruments.spirou.pseduo_const.get_mid_obs_time())

  • get the raw data type (via apero.core.instruments.spirou.pseduo_const.get_dprtype())

Raw file identification

This takes a given input file and checks it against the instrument file-definitions. The file-definitions give all the criteria by which an input file can be matched as a specific drs file type.

This is done via apero.science.preprocessing.identification.drs_infile_id() which in turn calls apero.core.core.drs_file.id_drs_file() and returns a tuple - whether the file was found in the instruments definition and the drs file type (DrsInputFile instance)

Gaia ID and object finding

We assume the header either has a Gaia ID column (defined by the KW_GAIA_ID keyword) or a valid object name (defined by the KW_OBJECTNAME keyword).

We then attempt to resolve parameters in the following order

  1. If OBJ_LIST_RESOLVE_FROM_DATABASE From a local database

    1. based on Gaia ID

    2. if Gaia ID is not found based on object name (from a list of aliases)

  2. If OBJ_LIST_RESOLVE_FROM_COORDS and if object was not found in local database but we have a Gaia ID then we get the Gaia parameters from the online Gaia catalog - if an object if found the local database is updated.

  3. If OBJ_LIST_RESOLVE_FROM_GLIST and if we did not have a Gaia id we then use a google sheet of known objects to match object names and Gaia ids (we can also add extra aliases here). If a Gaia ID/object name combination is found we then cross-match against the online Gaia catalog to get the Gaia parameters and again update the local database.

  4. If OBJ_LIST_RESOLVE_FROM_COORDS is True we then use the coordinates from the file header to cross-match with Gaia directly and again the local database is updated.

  5. If the Gaia id is still unknown we default to the astrophysical parameters in the header.

Note that the local object database should be updated before doing a full reprocessing and updating at any other time (other than adding new objects as above) may lead to inconsistent data sets.