Now let's add a third(!) Si channel to another spectrometer...
So we standardize using three spectrometers, but when we reanalyze our previous secondary standard (std 160), we see a problem:
St 160 Set 2 NBS K-412 mineral glass, Results in Elemental Weight Percents
ELEM: Si Si Si Fe Mg Ca Al Mn O
TYPE: ANAL ANAL ANAL SPEC SPEC SPEC SPEC SPEC SPEC
BGDS: LIN LIN LIN
TIME: 10.00 .00 .00 --- --- --- --- --- ---
BEAM: 30.02 .00 .00 --- --- --- --- --- ---
AGGR: 3 --- --- --- --- --- ---
ELEM: Si Si Si Fe Mg Ca Al Mn O SUM
XRAY: (ka) (ka) (ka) () () () () () ()
3 30.839 .000 .000 7.742 11.657 10.899 4.906 .077 43.597 109.717
AVER: 30.839 .000 .000 7.742 11.657 10.899 4.906 .077 43.597 109.717
SDEV: .000 .000 .000 .000 .000 .000 .000 .000 .000 .000
SERR: .000 .000 .000 .000 .000 .000 .000 .000 .000
%RSD: .00 .0000 .0000 .00 .00 .00 .00 .00 .00
PUBL: 21.199 n.a. n.a. 7.742 11.657 10.899 4.906 .077 43.597 100.077
%VAR: 45.47 .00 .00 .00 .00 .00 .00 .00 .00
DIFF: 9.640 --- --- .000 .000 .000 .000 .000 .000
STDS: 162 0 0 --- --- --- --- --- ---
STKF: .2018 .0000 .0000 --- --- --- --- --- ---
STCT: 134.76 .00 .00 --- --- --- --- --- ---
UNKF: .2412 .0000 .0000 --- --- --- --- --- ---
UNCT: 161.05 .00 .00 --- --- --- --- --- ---
UNBG: 2.46 .00 .00 --- --- --- --- --- ---
ZCOR: 1.2785 .0000 .0000 --- --- --- --- --- ---
KRAW: 1.1951 .0000 .0000 --- --- --- --- --- ---
PKBG: 66.40 .00 .00 --- --- --- --- --- ---
So what went wrong? Well our secondary standard 160, now has Si on three channels, but our primary std (162), still only has two channels for Si (note that the standard counts are still 134.76). So we have fewer counts on our primary standard when only two Si channels are aggregated, as opposed to three Si channels on our secondary standard (the sample being analyzed).
If we reacquire our primary standard with three Si channels, all is good again.
St 160 Set 2 NBS K-412 mineral glass, Results in Elemental Weight Percents
ELEM: Si Si Si Fe Mg Ca Al Mn O
TYPE: ANAL ANAL ANAL SPEC SPEC SPEC SPEC SPEC SPEC
BGDS: LIN LIN LIN
TIME: 10.00 .00 .00 --- --- --- --- --- ---
BEAM: 30.02 .00 .00 --- --- --- --- --- ---
AGGR: 3 --- --- --- --- --- ---
ELEM: Si Si Si Fe Mg Ca Al Mn O SUM
XRAY: (ka) (ka) (ka) () () () () () ()
3 21.410 .000 .000 7.742 11.657 10.899 4.906 .077 43.597 100.288
AVER: 21.410 .000 .000 7.742 11.657 10.899 4.906 .077 43.597 100.288
SDEV: .000 .000 .000 .000 .000 .000 .000 .000 .000 .000
SERR: .000 .000 .000 .000 .000 .000 .000 .000 .000
%RSD: .00 .0000 .0000 .00 .00 .00 .00 .00 .00
PUBL: 21.199 n.a. n.a. 7.742 11.657 10.899 4.906 .077 43.597 100.077
%VAR: .99 .00 .00 .00 .00 .00 .00 .00 .00
DIFF: .211 --- --- .000 .000 .000 .000 .000 .000
STDS: 162 0 0 --- --- --- --- --- ---
STKF: .2018 .0000 .0000 --- --- --- --- --- ---
STCT: 198.43 .00 .00 --- --- --- --- --- ---
UNKF: .1638 .0000 .0000 --- --- --- --- --- ---
UNCT: 161.05 .00 .00 --- --- --- --- --- ---
UNBG: 2.46 .00 .00 --- --- --- --- --- ---
ZCOR: 1.3070 .0000 .0000 --- --- --- --- --- ---
KRAW: .8116 .0000 .0000 --- --- --- --- --- ---
PKBG: 66.40 .00 .00 --- --- --- --- --- ---
Note that the standard counts are now 198.43 cps/nA.
This I believe is the reason for the problems that John Fournelle saw is his very complicated run. That is depending on whether it's the primary standard, or the secondary standard (or unknown), that has fewer or more duplicate elements acquired, the observed analytical total will either be too high or too low!
Bottom line, the software can handle elements in standards that are disabled (relative to the sample being analyzed), but it can't handle a situation in which the primary standard and another sample have different numbers of duplicate elements!
Edit by John: Or (I should add), the same number of duplicate elements, but not the same exact spectrometers!!!
Man, this gets complicated fast...