Hi Heiko,
the error on S/P from MC enriched goes from 10-15% in the first mX bins
to higher values, reaching 100% above 3.7 GeV or so. You can read these
numbers from cells I4-I13 and K4-K13 of the spreadsheets in
http://www.slac.stanford.edu/~bozzi/SoverP/SoverPFullRew.sxc
in addition to consider the uncertainty on the double ratio on the
depleted sample, we also need to correct the MC by the central value
(1.328). Also, I would really like to see what happens by cutting the
modes with pi0s in the garbage...
Concezio.
Heiko Lacker wrote:
> Hi Concezio,
>
> indeed, S and P are anti-correlated which increases the errors.
>
> What puzzles me a bit is the fact that the chi^2 is too good. In
> other words: At large mX the S/P value should fluctuate more than
> it is observed.
>
> If we believe in a constant the systematics on the individual mX bin
> for the double ratio would (e.g. for IP>0.2) be 0.1491/1.328: 11%.
>
> This should result in an interesting systematic error on DeltaBRBR
> when only taking S/P from MC-enriched and by randomizing S/P by 11%
> per bin. Of course, one should add still to this error also the error
> on S/P from MC-enriched.
>
> Cheers,
> Heiko
>
>
> On Thu, 5 Oct 2006, Concezio Bozzi wrote:
>
>
>> Heiko Lacker wrote:
>>
>>> * Concezio will produce (S/P)-double-ratios for depleted sample
>>> (data/MC) taking into account S/P-correlations in the error
>>> calculations in the data-depleted mES fit
>>>
>>>
>> plots which include the correlations are here:
>>
>> http://www.slac.stanford.edu/~bozzi/SoverP/SoverP_mcdata_depl_020.eps
>> http://www.slac.stanford.edu/~bozzi/SoverP/SoverP_mcdata_depl_030.eps
>> http://www.slac.stanford.edu/~bozzi/SoverP/SoverP_mcdata_depl_040.eps
>> http://www.slac.stanford.edu/~bozzi/SoverP/SoverP_mcdata_depl_050.eps
>>
>> the spreadsheet used to produce the plots is
>> http://www.slac.stanford.edu/~bozzi/SoverP/SoverPFullRew.sxc
>>
>> Please note that the correlations are not yet taken into account for
>> intpur>0.5, as I could not find the appropriate logfile. The effect of
>> the correlations is in any case small. Since the S and P are
>> ANTIcorrelated (as expected), the error on S/P increase.
>>
>> Here are the double S/P ratios (MC/data) for different intpur cuts, as
>> resulting from a simple p0 fit. Chisquares are also shown.
>>
>> intpur cut S/P chisquare/nDOF
>> 0.20 1.33 +/- 0.15 3.5/9
>> 0.30 1.41 +/- 0.16 2.9/9
>> 0.40 1.19 +/- 0.17 8.7/9
>> 0.50 1.25 +/- 0.17 8.4/9 (no correlations yet)
>>
>> I would say that data and MC depleted samples agree better and their
>> ratio is weakly dependent on mX at higher integrated purity cuts.
>> Ciao, Concezio.
>>
>>
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