PV DIS: SUSY and Higher Twist

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PV DIS SUSY and Higher Twist
S. Mantry, K. Lee, G. Sacco Caltech
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Outline

1. PV DIS new physics Model independent
   analysis SUSY effects
2. PV DIS Higher twist Puzzles from JLab
   data The twist expansion What does QCD
   predict? Q2-dependence, operator matrix
   elements
3. General remarks

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I. PV DIS New physics
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Model Independent Constraints
Low energy effective PV eq interaction
PV DIS eD asymmetry leading twist
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Model Independent Constraints
P. Reimer, X. Zheng
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QW and SUSY Radiative Corrections
Tree Level
Radiative Corrections
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SUSY Radiative Corrections
Propagator
Box
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SUSY RPV Effects
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Comparing AdDIS and Qwp,e
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Probing SUSY with PV eN Interactions
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Lepton Flavor Number Violation
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II. PV DIS Higher Twist
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Probing the strange sea with PV
GMs 0.28 /- 0.20 GEs -0.006 /- 0.016 3
/- 2.3 of proton magnetic moment 20 /- 15
of isoscalar magnetic moment 0.2 /- 0.5 of
Electric distribution
Consistent with s-quark contributions to mP JP
but smaller than early theoretical expectations
Preliminary
Courtesy of Kent Pashke (U Mass)
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Probing Higher Twist Beyond the Parton Model
2xF1 Experimental Status
Data from JLab E94-110 (nucl-ex/0410027,
submitted to PRL) Courtesy C Keppel
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n 2 Cornwall-Norton Moments
F2
F2, F1 in excellent agreement with NNLO TM
above Q2 2 GeV2 No (or canceling) higher
twists Yet, dominated by large x and resonance
region Remove known HT (a bit novel), the
elastic, and there is no more down to Q2 0.5
GeV2 The case looks different for FL (data or
curve?)
2xF1
FL
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Twist Expansion
Light cone expansion x2 0
Momentum sum rules
Twist d(n) - j
Power corr
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Twist Expansion
Light cone expansion x2 0
Momentum sum rules
Twist d(n) - j
Power corr
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Twist Expansion Q2 Evolution
Twist two
Singlet moments 2 x 2 mixing only
Twist four correlations
Operator mixing basis size grows with n (for nth
moment)
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Twist Expansion Q2 Evolution
Equivalence to parton model twist two
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Twist Expansion Q2 Evolution
Twist two
Singlet moments 2 x 2 mixing only
Twist four correlations
Operator mixing basis size grows with n (for nth
moment)
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Probing Higher Twist Beyond the Parton Model
2xF1 Experimental Status
Data from JLab E94-110 (nucl-ex/0410027,
submitted to PRL) Courtesy C Keppel
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n 2 Cornwall-Norton Moments
F2
F2, F1 in excellent agreement with NNLO TM
above Q2 2 GeV2 No (or canceling) higher
twists Yet, dominated by large x and resonance
region Remove known HT (a bit novel), the
elastic, and there is no more down to Q2 0.5
GeV2 The case looks different for FL (data or
curve?)
2xF1
FL
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Probing Higher Twist with PV
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III. General remarks

• PV DIS provides a comprehensive probe of QCD
  beyond the parton model possible deviations
  from the SM EW sector
• Looking beyond the parton model is a natural
  continuation of the JLab strange quark
  searches
• Rich set of challenges for theory experiment
  higher twist, CSB in pdfs, d/u
• Important complement to 12 GeV Moller that would
  be a focused and powerful probe of EW SM
  possible new physics