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Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 11
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 22
IntroductionIntroduction
Baryon SpectroscopyBaryon Spectroscopy
What's in Hall B? What's in Hall B?
CLASCLAS
Tagged polarized photon beamsTagged polarized photon beams
FROzen Spin TargetFROzen Spin Target
Glimpse of the dataGlimpse of the data
OutlookOutlook
SummarySummary
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 33
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 44
N*N*
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 55
ExperimentExperimentcross section, cross section,
spin observablesspin observables
ExperimentExperimentcross section, cross section,
spin observablesspin observables
TheoryTheoryLQCD,LQCD,
quark models,quark models,QCD sum rulesQCD sum rules,
…
TheoryTheoryLQCD,LQCD,
quark models,quark models,QCD sum rulesQCD sum rules,
…
Reaction TheoryReaction Theorydynamical frameworksdynamical frameworks
Reaction TheoryReaction Theorydynamical frameworksdynamical frameworks
Amplitude analysisAmplitude analysis→→multipole amplitudesmultipole amplitudes
→→phase shiftsphase shifts
Amplitude analysisAmplitude analysis→→multipole amplitudesmultipole amplitudes
→→phase shiftsphase shifts
σ,dσ/dΩ,Σ,P,Tσ,dσ/dΩ,Σ,P,T
(beam-target)(beam-target) E,F,G,H, E,F,G,H,(beam-recoil)(beam-recoil) C Cxx,C,Czz,O,Oxx,O,Ozz,,(target-recoil)(target-recoil) L Lxx,L,Lzz, T, Txx,T,Tzz,,
Coupled channels:Coupled channels: resonance parameter resonance parameter
extractionextraction
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 66
I. S. Barker, A. Donnachie, J. K. Storrow, Nucl. Phys. B95I. S. Barker, A. Donnachie, J. K. Storrow, Nucl. Phys. B95,, 347 347 (1975).(1975).I. S. Barker, A. Donnachie, J. K. Storrow, Nucl. Phys. B95I. S. Barker, A. Donnachie, J. K. Storrow, Nucl. Phys. B95,, 347 347 (1975).(1975).
44 Complex amplitudes - Complex amplitudes - 1616 real polarization observables. real polarization observables.A A complete measurement fromcomplete measurement from 88 carefully chosen carefully chosen observablesobservables. .
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 77
Emax ~ 6 GeVEmax ~ 6 GeVImax ~ 200 Imax ~ 200 AADuty Factor ~ 100%Duty Factor ~ 100%E/E ~ 2.5 10-5E/E ~ 2.5 10-5Beam P Beam P ≥≥ 80% 80%EE ~ 0.5-5.8 GeV ~ 0.5-5.8 GeV taggedtagged
Hall-BHall-BHall-BHall-B
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 88
Torus magnetTorus magnet6 superconducting coils6 superconducting coils
Gas Cherenkov countersGas Cherenkov counterse/e/ separation, 256 PMTs separation, 256 PMTs
Time-of-flight countersTime-of-flight countersplastic scintillators, 684 plastic scintillators, 684 photomultipliersphotomultipliers
Drift chambersDrift chambers35,000 cells35,000 cells
Liquid DLiquid D2 2 (H(H22) target +) target +
start counter; e mini-start counter; e mini-torustorus
Electromagnetic calorimetersElectromagnetic calorimetersLead/scintillator, 1296 photomultipliersLead/scintillator, 1296 photomultipliers
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 99
61 backing counters
Jefferson Lab Hall B Jefferson Lab Hall B photon tagger:photon tagger:
EE = 20-95% of E = 20-95% of E00
EE up to ~5.8 GeV up to ~5.8 GeV
dE/E ~10dE/E ~10-3-3 of E of E00
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1010
Circularly polarized beam Circularly polarized beam produced by longitudinally produced by longitudinally polarized electronspolarized electrons
CEBAF electron beam CEBAF electron beam polarization >85%polarization >85%
tagged flux ~ 50 - 100MHz (for k>0.5 Etagged flux ~ 50 - 100MHz (for k>0.5 E00
2
2
344
4
kk
kkPP e
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1111
Linearly polarized photons: coherent Linearly polarized photons: coherent bremsstrahlung on oriented diamond crystalbremsstrahlung on oriented diamond crystal
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1212
existing dynamically polarized existing dynamically polarized NHNH33, , NDND
3 3 targettarget
polarizing magnet 5.1 T polarizing magnet 5.1 T Helmholtz coilsHelmholtz coils
reduces acceptance to θ<65reduces acceptance to θ<65oo
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1313
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1414
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1515
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1616
4 layers of superconductive wire4 layers of superconductive wireField 0.54 TField 0.54 TNo visible losses of polarization while doing spin No visible losses of polarization while doing spin rotation →↑rotation →↑
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1717
butanolbutanol
1212CCCHCH
22
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1818
Base Base temperaturetemperature
Cooling powerCooling power
PolarizationPolarization
1/e relaxation 1/e relaxation timetime
Design goalDesign goal
<50 mK<50 mK
1010W (Frozen)W (Frozen)mW (Polarizing) 20mW (Polarizing) 20
80%80%
hours 500hours 500
mK 50>mK 50>
1010W (Frozen)W (Frozen)20 mW (Polarizing)20 mW (Polarizing)
80%80%
500 hours500 hours
28 mK w/o beam28 mK w/o beam30 mK with beam30 mK with beam
800 800 W @50 mKW @50 mK10 mW @ 100 mK10 mW @ 100 mK60 mW @300 mK60 mW @300 mK
+82%+82%-85%-85%
2800 hours (+Pol)2800 hours (+Pol)hours (-Pol 1600hours (-Pol 1600((
mK w/o beam 28mK w/o beam 28mK with beam 30mK with beam 30
800 800W @50 mKW @50 mKmW @ 100 mK 10mW @ 100 mK 10mW @300 mK 60mW @300 mK 60
82%+82%+85%-85%-
hours (+Pol) 2800hours (+Pol) 28001600 hours (-Pol1600 hours (-Pol))
ResultResult
Excellent reliability! Continuously running October 29 – February Excellent reliability! Continuously running October 29 – February 12. 12.
Entire repolarization procedure takes under 6 hoursEntire repolarization procedure takes under 6 hoursTake data for 5-6 daysTake data for 5-6 days
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 1919
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2020
g1g1: : EE = 0.5 – 2.9 GeV circularly polarized beam = 0.5 – 2.9 GeV circularly polarized beam
γγp→πp→π00p, πp, π++nn dd/d/d
γγp→ηpp→ηp dd/d/d
γγp→η'p p→η'p dd/d/d
γγp→KY (Kp→KY (K++Λ, KΛ, K++ΣΣ00, K, K00ΣΣ++) ) dd/d/d, , P, CP, C
x'x'/C/Cz'z'
γγp→πp→π++ππ--pp
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2121
g8g8: : EE = 0.9 – 2.1 GeV Linearly polarized = 0.9 – 2.1 GeV Linearly polarized
γγp→πp→π00p, πp, π++nn
γγp→ηp p→ηp
γγp→η'p p→η'p
γγp→KY (Kp→KY (K++Λ, KΛ, K++ΣΣ00, K, K00ΣΣ++) ) , , P, T, OP, T, O
xx/O/Ozz
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2222
R. Schumacher
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2323
Nikanov et al’.’s refit of Bonn-Gachina multi-coupled-channel isobar modelmix includes: S11 wave, P13(1720), P13(1900), P11(1840)K+Σ0cross sections also better described with P13(1900)Promote this “missing”resonance from ** to **** status.P13(1900) is found in qqq quark models, but not in quark-diquark models
R. Schumacher
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2424
2 2 2x zR P C Cº 2 2 2x zR P C Cº
The The appears 100% polarized when created with a fully appears 100% polarized when created with a fully polarized beam.polarized beam.
R. Schumacher
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2525
R. Schumacher
Energy and angle averages are consistent with unity.
No such effect with linearly polarized photons.
No such effect for
2 2 2x zR P C Cº
1 .0 1 0 .0 1R ±
No model predicted this CLAS result.
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2626
Polarized beam still is not enough, we Polarized beam still is not enough, we need polarized target!need polarized target!
E02-112:E02-112: γp→KY γp→KY (K(K++ΛΛ, K, K++ΣΣ00, K, K00ΣΣ++))
E03-105/E04-102: E03-105/E04-102: γp→πγp→π00p, πp, π++nn
E05-012:E05-012: γp→ηpγp→ηp
E06-013:E06-013: γp→πγp→π++ππ--pp
We can do “Complete experiment” for We can do “Complete experiment” for KY! KY!
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2727
November 3, 2007– February 12, 2008November 3, 2007– February 12, 2008
Longitudinally polarized targetLongitudinally polarized target
Circularly and linearly polarized photon beam 0.5-Circularly and linearly polarized photon beam 0.5-2.4 GeV2.4 GeV
Trigger: at least one charged particle in CLASTrigger: at least one charged particle in CLAS
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2828
Helicity asymmetry Helicity asymmetry EE
Raw asymmetryRaw asymmetry
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 2929
Circularly polarized photon beam on longitudinally Circularly polarized photon beam on longitudinally polarized targetpolarized target
E, E, PP, Lx/Lz, , Lx/Lz, Cx/CzCx/Cz
Linearly polarized photon beam on longitudinally polarized Linearly polarized photon beam on longitudinally polarized targettarget
, G, , G, PP, (Tx/Tz) , (Tx/Tz) Ox/OzOx/Oz
Circularly polarized photon beam on transversely polarized Circularly polarized photon beam on transversely polarized targettarget
T, F, T, F, PP,, Tx/Tz, Tx/Tz, Cx/CzCx/Cz
Linearly polarized photon beam on transversely polarized Linearly polarized photon beam on transversely polarized targettarget
, H, T, P, , H, T, P, (Lx/Lz) (Lx/Lz)
Complete
Scheduled fo
r 2010
Scheduled fo
r 2010
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 3030
To reveal isospin structure it is essential To reveal isospin structure it is essential to do measurements on the neutronto do measurements on the neutron
G13 running period accumulated large G13 running period accumulated large dataset with circularly an linearly dataset with circularly an linearly polarized photons on liquid deuterium polarized photons on liquid deuterium unpolarized targetunpolarized target
The data are being analizedThe data are being analized
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 3131
A. Sandorfi
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 3232
A. Sandorfi
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 3333
New addition in Hall B of Frozen Spin Target, with both, New addition in Hall B of Frozen Spin Target, with both, longitudinal and transverse polarization significantly advances longitudinal and transverse polarization significantly advances our experimental capabilities.our experimental capabilities.
It is possible to perform It is possible to perform completecomplete experiment of KY experiment of KY photoproduction and photoproduction and nearly complete nearly complete for other final states.for other final states.
Entire program is more than just a sum of several experiments, Entire program is more than just a sum of several experiments, observables for all final states are measured simultaneously observables for all final states are measured simultaneously under the same experimental conditions and have the same under the same experimental conditions and have the same systematic uncertainties. systematic uncertainties.
It can be considered as “It can be considered as “coupled channel experimentcoupled channel experiment” ultimately ” ultimately providing data for providing data for coupled channel analysis coupled channel analysis and extraction of and extraction of parameters of baryon resonances.parameters of baryon resonances.
Supply data EBAC – Excited Baryon Analysis Center at JLABSupply data EBAC – Excited Baryon Analysis Center at JLAB
Experiments with HD-Ice target are in preparationExperiments with HD-Ice target are in preparation
Eugene Pasyuk Eugene Pasyuk DSPIN-09 DSPIN-09 Dubna, September 1-5, 2009Dubna, September 1-5, 2009 3434
The CLAS Collaboration
Idaho State University, Pocatello, IdahoINFN, Laboratori Nazionali di Frascati, Frascati, Italy
INFN, Sezione di Genova, Genova, ItalyInstitut de Physique Nucléaire, Orsay, France
ITEP, Moscow, RussiaJames Madison University, Harrisonburg, VAKyungpook University, Daegu, South KoreaUniversity of Massachusetts, Amherst, MA Moscow State University, Moscow, RussiaUniversity of New Hampshire, Durham, NH
Norfolk State University, Norfolk, VAOhio University, Athens, OH
Old Dominion University, Norfolk, VA
Arizona State University, Tempe, AZUniversity of California, Los Angeles, CACalifornia State University, Dominguez Hills, CACarnegie Mellon University, Pittsburgh, PACatholic University of AmericaCEA-Saclay, Gif-sur-Yvette, FranceChristopher Newport University, Newport News, VAUniversity of Connecticut, Storrs, CTEdinburgh University, Edinburgh, UKFlorida International University, Miami, FLFlorida State University, Tallahassee, FLGeorge Washington University, Washington, DCUniversity of Glasgow, Glasgow, UK
Rensselaer Polytechnic Institute, Troy, NYRice University, Houston, TX
University of Richmond, Richmond, VAUniversity of South Carolina, Columbia, SC
Thomas Jefferson National Accelerator Facility, Newport News, VA
Union College, Schenectady, NYVirginia Polytechnic Institute, Blacksburg, VA
University of Virginia, Charlottesville, VACollege of William and Mary, Williamsburg, VAYerevan Institute of Physics, Yerevan, Armenia
Brazil, Germany, Morocco and Ukraine, as well as other institutions in France and in the USA,
have individuals or groups involved with CLAS, but with no formal collaboration at this stage.
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