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оригинального документа
: http://xmm.vilspa.esa.es/sas/6.5.0/doc/omsrclistcomb/node5.html
Дата изменения: Tue Aug 16 05:59:32 2005 Дата индексирования: Sat Dec 22 13:31:05 2007 Кодировка: |
Standard magnitudes can only be computed for the U, B and V filters and hence the only standard colours that can be calculated are U-B, B-V and U-V. An important point to note, is that these standard colours can be computed using the following instrumental colours - U-B, B-V, U-V, (UVW1-U), (UVW1-B), (UVW1-V), (UVW2-B) and (UVW2-V). Omsrclistcomb computes all possible standard magnitudes for each of the U, B and V filters and displays them in a vector column.
The program loops through these colours and if the relevant instrumental magnitudes are present computes the standard magnitudes and standard colour. Since it is possible that a particular source may have a standard magnitude computed twice for the same filter (eg standard B from U-B and B-V), the program will add, if necessary, a column for each of these standard magnitudes. These values should, of course, be identical to within the errors, but discrepancies may arise due to a number of reasons (eg an inaccurate instrumental magnitude).