Physics Results: Parton Distribution Functions: What Can We Learn With All Six Structure Functions

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Physics Results Parton Distribution
FunctionsWhat Can We Learn With All Six
Structure Functions?
Recall Neutrinos?have the ability to directly
resolve flavor of the nucleons constituents
??interacts with d, s, u, and c while
??interacts with u, c, d and s.
Using Leading order expressions

• Does s s and c c over all x?
• If so.....

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Physics Results Six Structure Functions for
Maximal Information on PDFs
R Rwhitlow Neutrino 1 year he-beam Anti-Neutri
no 2 years he-beam
y2 FL
X 0.1 - 0.125 Q2 2 - 4 GeV2 Kinematic cuts in
(1-y) not shown
(1-y)2
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Nuclear Effects - studied only with charged
leptons
S. Kumano
Fermi motion
valence-quark
original EMC finding
antiquark
shadowing
x
sea quark
valence quark
EXPECTED to be different for n!!
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Nuclear Effects
Q2 distribution for SciBar detector
Problem has existed for over two years
All known nuclear effects taken into
account Pauli suppression, Fermi Motion, Final
State Interactions They have not
included low-n shadowing that is only
allowed with axial-vector (Boris Kopeliovich at
NuInt04) Lc 2n / (mp2 Q2) RA (not mA2)
Lc 100 times shorter with mp allowing low n-low
Q2 shadowing ONLY MEASURABLE VIA NEUTRINO -
NUCLEUS INTERACTIONS! MINERnA WILL MEASURE
THIS ACROSS A WIDE n AND Q2 RANGE WITH C
Fe Pb
Larger than expected rollover at low Q2
MiniBooNE From J. Raaf (NOON04)
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Nuclear EffectsDifference between n-A and m-A
nuclear effects
Sergey Kulagin