The SRCLIST table has the following keywords:
The SRCLIST table has the following columns:
Column name: | Data type: | Description: |
INDEX | int16 | Source index number. Each source has a unique value, which rgssources never alters. |
LABEL | string | Label for the source. These values are also unique to each source. Only upper case is used. At present, label values can only be 20 characters or less in length. Trailing spaces are not allowed. |
RA | real32 | J2000 right ascension in decimal degrees. |
DEC | real32 | J2000 declination in decimal degrees. |
RATE | real32 | Counts per second. |
DELTA_DISP | real32 | Offset on the sky, in the dispersion direction, of the source with respect to the pointing direction. Given in arcminutes. |
DELTA_XDSP | real32 | Offset on the sky, in the cross-dispersion direction, of the source with respect to the pointing direction. Given in arcminutes. |
FOV_PHI | real32 | This and the next column give the polar coordinates of DELTA_DISP and FOV_PHI. Units for both are decimal degrees. FOV_PHI is the angle of the source position from the -ve dispersion axis towards the +ve cross-dispersion axis. |
FOV_R | real32 | |
CONFUSION | real32 | This is a measure of how confused the source is with respect to the prime source. See subsection 5.2 for a description of how it is calculated. It is a dimensionless number. |
PROCESS | bool | This column is used by rgsregions to flag those sources for which spectrum extraction regions should be calculated. This column is no longer set by rgssources, so all values are written as false. |
BKG_EXCLUDE | bool | This column is used by rgsregions to flag those sources which should be excluded from the background spectrum extraction region. This column is no longer set by rgssources, so all values are written as false. |
FIXED_ON_SKY | bool | This column flags those sources for which the positional information was derived from right ascension and declination. The only sources for which FIXED_ON_SKY is false are the attitude source and any user source supplied with userstyle=`wtatt'. |
EPIC_FILE | int16 | This gives the number of the E_EXPRn, E_CONTn, E_BANDn and E_FILTn keywords appropriate to the source if it has been derived from an EPIC source list. Eg, for EPIC_FILE=3, the details of the original list from which this source came can be found from the keywords E_EXPR3, E_CONT3, E_BAND3 and E_FILT3. |
Note that the RGS source list set is also used to store the spectrum extraction regions created by rgsregions. These become invalidated if the attitude is altered; in this case rgssources deletes them. See the algorithm (section 7) for details of the circumstances under which this occurs.
The RGS source list table is required to have 1 source whose position is taken from the observation proposal, and 1 source whose position is equal to the RGS attitude (stored in the dataset header keywords RA_PNT, DEC_PNT and PA_PNT). The LABEL values of these two sources are PROPOSAL and ONAXIS respectively.