Parameters

 Keyword  Position  Type       Description
 -------  --------  ----       -----------
 INSTR        1      CHAR       Instrument name  e.g. 'WFC' or 'XRT'
 SCOUNT       2      REAL       Total counts from source
 BCOUNT       3      REAL       Counts from background per square arcmin
 AZIMUTH      4      REAL       Off-axis azimuth (arcmin)
 ELEV         5      REAL       Off-axis elevation (arcmin)
 ENERGY              REAL       Mean energy of source photons (keV)
 DMJD                DOUBLE     Modified Julian date of observation
                                         (WFC only)
 IFILT               INTEGER    WFC filter number
 DISP                LOGICAL    Display the result ?
    Default = YES
 RADIUS     output   REAL       Radius of circle giving best S/N ratio
                                          (arcmin)
 MAXFRAC    output   REAL       Fraction of counts within best radius

• BCOUNT
• DMJD
• ENERGY
• IFILT
• SCOUNT