Calculate Hardness Ratios

 

Hardness ratios can be calculated from lists of counts determined   in two energy bands by the command

CALCULATE/HARDNESS_RATIO hrpar edit

  The parameter file hrpar.par can also be created by the command

CREATE/PARFIL HR hrpar

In Table 5.14 all parameters showing up in the parameter file hrpar.par are listed. An explanation is given only for those parameters, which are active.

  
Table 5.14: Parameter file for CALCULATE/HARDNESS_RATIO

The hardness ratio HR and the error in the hardness ratio E_HR is calculated as:  

with







with CTS_1 and CTS_2, the counts in the band 1 and 2, CERR_1 and CERR_2, the errors in counts in the band 1 and 2, VIG_COR_1 and VIG_COR_2, the vignetting correction factor   ( ) for bands 1 and 2. Standard settings for ROSAT PSPC energy bands are:

An explanation of the parameters from Table 5.14 follows. UL_LIST_1 and UL_LIST_2 is the table UL_LIST_ALL from the upper limit counts calculation program (see section 5.2.15), applied to the first (second) energy band. RESULT_TABLE is the table containing the calculated hardness ratio and the error in hardness ratio.

  
Table 5.15: Column labels for table hrlst.tbl

Note:In case the error in counts in one of the bands is 0., an error in hardness ratio of 0. will be given.