Investigate model uncertainties OLD/NEW But what about u,d,s,c?

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Investigate model uncertaintiesOLD/NEW But what
about u,d,s,c?
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OLD
NEW
Now there really IS a big new/old difference
..where does it come from in detail? (dont
bother looking at the blue lines- thats another
story)
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NEW
OLD
For the variation of fs, new/old look pretty much
the same- as they should
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NEW
Variation of mb
OLD
Old had mb and mc -neither made any
difference New has JUST mb.. it is no longer true
that changing mc gives no model dependence! For
variation of mb NEW/OLD are the same
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NEW
Variation of Q2min
OLD
Variation of the Q2 cut NEW/OLD similar- slight
difference in cbar
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NEW
OLD
Old had mb and mc New 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
Variation of fc
OLD
Varaition of fc used to make a difference because
it was imposed. But with dynamic generation fc
does NOT change the amount of cbar Only the Ubar
Dbar relative norm has changed we CANt Agree
on this unless we both do it dynamically
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NEW
Change of Q20
OLD
Change of Q20 used to affect the flavour break up
a lot because fs and fc were not changed
accordingly. Now that fs anf fc are changed with
Q20, the change of Q20 itself is not a big effect.
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LEFT 6 model variations RIGHT 6 model variations
PLUS alphas variation Change of alphas does
affect cbar slightly because it is now
dynamically generated from the gluon!
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Comparsion of NEW standard to other
parametrisations H1 and humpy are not dynamic-
this seems to affect high-x cbar most.