Investigate model uncertainties OLD/NEW

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Investigate model uncertaintiesOLD/NEW
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NEW
OLD
Include only variation of charm mass and beauty
mass mc1.35?1.5 GeV and mb 4.3 ?5.0 GeV This
model dependence was invisible and its still
invisible
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NEW
OLD
Include only variation of charm mass and beauty
mass mc1.35?1.5 GeV and mb 4.3 ?5.0 GeV This
model dependence was invisible and its still
invisible
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NEW
OLD
Include only variation of strange fraction fs
0.25 ?0.40 Makes very little difference in the
total Sea, but affects sea flavour
break-up New/OLD look the same
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NEW
OLD
Include only variation of strange fraction fs
0.25 ?0.40 Makes very little difference in the
total Sea, but affects sea flavour
break-up NEW/OLD look the same
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NEW
OLD
Include only variation of charm fraction fc
0.10 ?0.20 OLD 0.07 ? 0.11 NEW A smaller
effect than fs makes very little difference in
the total Sea, but affects sea flavour break-up
Couldnt see it before- Cant see it now!
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NEW
OLD
NEW
Include only variation of charm fraction fc
0.10 ?0.20 OLD 0.07 ? 0.11 NEW A smaller
effect than fs makes very little difference in
the total Sea, but affects sea flavour break-up
This model dependence is smaller now as it should
be!
If you look at flavour break-up U/D you can see
that the fc matters less than it did..make a tif
file?
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NEW
OLD
Include only variation of starting scale Q02 2 ?
6 GeV2 Has a small asymmetric effect on PDF
ucertainties NEW/OLD look the same
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NEW
OLD
Include only variation of starting scale Q02 2 ?
6 GeV2 Has a small asymmetric effect on PDF
ucertainties NEW has slightly smaller model
dependence than old- this is also as expected
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NEW
OLD
Include only variation of minimum Q2 of fitted
data Qmin2 2.5 ? 5 GeV2 Has an even smaller
asymmetric effect on PDF ucertainties NEW/OLD
look the same
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NEW
OLD
Include only variation of minimum Q2 of fitted
data Qmin2 2.5 ? 5 GeV2 Has an even smaller
asymmetric effect on PDF uncertainties NEW/OLD
look the same
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But what about u,d,s,c?
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BUT we never showed the world flvaour break-up
OLD
Now there really IS a new/old difference ..where
does it come from?
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NEW
But look at flavour break-up
OLD
Old has just mb and mcNew haS JUST mb..beacuse
it is no longer true that changing mc gives no
model dependence!
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NEW
OLD
Old has just mb and mcNew haS JUST mc.. it is no
longer true that changing mc gives no model
dependence! This makes sense. In dynamic
generation the amount of charm does change with mc
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NEW
But look at flavour break-up
OLD
For the variation of fs, flavour break-up has not
changed- good!
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NEW
But look at flavour break-up
OLD
NEW
Fc used to make a difference because it was
imposed. But with dynamic generation fc does Not
change only the Ubar Dbar relative norm has
changed
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NEW
OLD
Change of Q0 used to affect the flavour break up
a lot because fs and fc were not changed
accordingly. Now they are changed it is not a big
effect. I think this makes sense
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NEW
OLD
The effect of the Q2 cut is small..can be seen in
cbar
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Change of alphas does affect cbar slightly it is
now dynamically generated from the gluon!
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