cdf results on diffraction and exclusive production
DESCRIPTION
14th Workshop on Elastic and Diffractive Scattering (EDS Blois Workshop ). CDF RESULTS ON DIFFRACTION and EXCLUSIVE PRODUCTION. Konstantin Goulianos. Frontiers of QCD: From Puzzles to Discoveries December 15-21, 2011, Qui Nhon , Vietnam. CONTENTS. - PowerPoint PPT PresentationTRANSCRIPT
CDF RESULTS ON DIFFRACTION and EXCLUSIVE PRODUCTION
Konstantin Goulianos
14th Workshop on Elastic and Diffractive Scattering (EDS Blois Workshop)
Frontiers of QCD: From Puzzles to DiscoveriesDecember 15-21, 2011, Qui Nhon, Vietnam
EDS 2011 Vietnam Diffractive & exclusive production in CDF
CONTENTS Diffractive W and Z production……………………..published Diffractive structure function in dijet production ..…updated Rapidity gaps between jets………….......................updated
__________________________________________________ Diffr. structure function at low x using rap-gaps .….difficult ! Diffr. structure function in DPE dijet production…. ..delayed
__________________________________________________ Exclusive gg production in pp collisions at 1.96 TeV….NEW!
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EDS 2011 Vietnam Diffractive & exclusive production in CDF
In LO QCD W probes the quark content of diffractive exchange.
Production by gluons is suppressed by a factor of aS and distinguished by an associated jet.
Diffractive W/Z
MW
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EDS 2011 Vietnam Diffractive & exclusive production in CDF
MW from inclusive We/m+vMethod: compare transverse MW data with MC
MWdiff= 80.9± 0.7(GeV/c2)
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EDS 2011 Vietnam Diffractive & exclusive production in CDF
Diffractive W/Z fractions
~80% 68-80% ~87% f1-int =(25.6±1.2)%
RW (0.03 < x < 0.10, |t|<1)= [1.00 ± 0.05(stat.) ± 0.10(syst.)]%
Run I: RW =1.15±0.55 % for xmin<x<0.1 [0.97±0.47 (stat. & syst.) % within 0.03 < x < 0.10 & |t|<1
RZ (0.03 < x < 0.10, |t|<1)= [0.88 ± 0.21(stat.) ± 0.08(syst.)]%
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EDS 2011 Vietnam
Diffractive Structure Function in Dijets
)(xF)(xF
BjNDjj
BjSDjj
)(xRate)(xRate
)R(xBj
NDjj
BjSDjj
Bj Þº
Diffractive & exclusive production in CDF 6
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DSF: Q2 - dependence
ETjet ~ 100 GeV !
Small Q2 dependence in region 100<Q2<10 000 GeV2
where dsSD/dET & dsND/dET vary by a factor of ~104 !
The Pomeron evolves as the proton !EDS 2011 Vietnam Diffractive & exclusive production in CDF 7
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EDS 2011 Vietnam Diffractive & exclusive production in CDF
Dijet ET distributions
similar for SD and ND over 4 orders of magnitude Kinematics
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EDS 2011 Vietnam Diffractive & exclusive production in CDF
t – dependence: |t|<1 (GeV/c)^2
No diffraction dips No Q2 dependence up to to Q2~104 GeV2
Fit ds/dt to a double exponential: Same slope over entire region ~1 < Q2 < ~ 10 000 GeV2!
0.05 < x < 0.08b1
b2
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EDS 2011 Vietnam Diffractive & exclusive production in CDF
|t| up to 4 (GeV/c)2
diffractive dip region?
must reevaluate errors!10
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EDS 2011 Vietnam Diffractive & exclusive production in CDF
Asymmetric t distributions: A tool for evaluating background level!
• • 2 mm
2.5 mmpp7.5 mm
12.5 mm
x
Y
25 mm
tracker’s upper edge: |t|=2.3 (GeV/c)^2, estimated from t~q^2 the lower edge is at |t|= 6.5 (GeV/c)^2 (not shown) background level: region of Ytrack>Yo data for |t|>2.3 (GeV/c)^2
bgd =2 evts/(GeV/c)2
schematic view of fiber tracker t-distributions
Y = 7.5 mm
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EDS 2011 Vietnam Diffractive & exclusive production in CDF
RPS acceptance vs. t and x
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gaps between jets
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