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N*ews from COSY. May 2011 | Hans Ströher (Forschungszentrum Jülich, Germany). N*ews from COSY – Outline. COSY-facility Detection systems Selected recent results . N*ews from COSY – Storage Ring. Cooler and storage ring for (polarized) protons and deuterons p = 0.3 – 3.7 GeV/c
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N*ews from COSY May 2011 | Hans Ströher (Forschungszentrum Jülich, Germany)
N*ews from COSY – Outline COSY-facility Detection systems Selected recent results
N*ews from COSY – Storage Ring Cooler and storage ring for (polarized) protons and deuterons p = 0.3 – 3.7 GeV/c Phase space cooled internal & extracted beams COSY e-Cooler Injector cyclotron
N*ews from COSY – Storage Ring Cooler and storage ring for (polarized) protons and deuterons p = 0.3 – 3.7 GeV/c Phase space cooled internal & extracted beams COSY e-Cooler … the machine for spin physics with hadron beams Injector cyclotron
N*ews from COSY – Experiments • Hadron physics with hadronic probes • Experimental set-ups: • ANKE • WASA • EDM • TOF • NEW: • PAX WASA ANKE EDM PAX TOF
N*ews from COSY – Experiments • Hadron physics with hadronic probes • Experimental set-ups: • ANKE • WASA • EDM • TOF • NEW: • PAX WASA ANKE EDM PAX TOF Future plan/project: srEDM
N*ews from COSY – Experiments • ANKE: • forward magnetic spectrometer • solid, gas-jet, polarized targets • double polarization experiments • TOF: • large acceptance non-magnetic det. • liquid hydrogen, deuterium targets • (non-)strange meson, hyperon prod. • WASA: • ~4p electromagnetic calorimeter • thin superconducting solenoid • hydrogen, deuterium pellet target • symmetries and symmetry violation
N*ews from COSY – Experiments • ANKE: • forward magnetic spectrometer • solid, gas-jet, polarized targets • double polarization experiments • TOF: • large acceptance non-magnetic det. • liquid hydrogen, deuterium targets • (non-)strange meson, hyperon prod. • WASA: • ~4p electromagnetic calorimeter • thin superconducting solenoid • hydrogen, deuterium pellet target • symmetries and symmetry violation
N*ews from COSY – Experiments • ANKE: • forward magnetic spectrometer • solid, gas-jet, polarized targets • double polarization experiments • TOF: • large acceptance non-magnetic det. • liquid hydrogen, deuterium targets • (non-)strange meson, hyperon prod. • WASA: • ~4p electromagnetic calorimeter • thin superconducting solenoid • hydrogen, deuterium pellet target • symmetries and symmetry violation
N*ews from COSY – General • N N N N* [N N] X (= g, p, h, …) NN fusion: p N(+) (N N*)+(+) d p(+) • D-resonance Mostly:noresonancestructure, since 3(4)-body phase-space & strong FSI • invariant massdistributions COSY HADES at GSI
N*ews from COSY – General N N N N* [N N] X (= g, p, h, …) Special cases, e.g. p p p p p0p0 Roper COSY WASA at CELSIUS
N*ews from COSY – General N N N N* N K Y (hyperons) Isospin(-filter): K L only N*resonances, e.g. N*(1650, 1675, 1680,1700, 1710, 1720, 1840, 1875, 1900) K Sboth N* andD*resonances, e.g. D*(1600, 1620, 1700, 1750, 1900) Polarization(target, beam): K+, p, Lasymmetries, Lpolarization COSY
N*ews from COSY – Results (I) p p p K+ Y0 (Y0 = L, S0) TOF
N*ews from COSY – pp pK+ (L;S0) Reaction: pp p K+ (p p-) 3 beam energies: pp = 2.95 GeV/c (QL = 204, QS = 124 MeV); 3.06 GeV/c (239, 162 MeV); 3.20 GeV/c (284, 207 MeV) Primary and secondary V-shape; charged multiplicity jump; ToF
N*ews from COSY – pp pK+ (L;S0) Reaction: pp p K+ (p p-) 3 beam energies: pp = 2.95 GeV/c (QL = 204, QS = 124 MeV); 3.06 GeV/c (239, 162 MeV); 3.20 GeV/c (284, 207 MeV) Primary and secondary V-shape; charged multiplicity jump; ToF Result: (1) COSY-TOF collaboration, EPJ A 46, 27 – 44 (2010)
N*ews from COSY – pp pK+ (L;S0) Reaction: pp p K+ (p p-) 3 beam energies: pp = 2.95 GeV/c (QL = 204, QS = 124 MeV); 3.06 GeV/c (239, 162 MeV); 3.20 GeV/c (284, 207 MeV) Primary andsecondary V-shape; chargedmultiplicity jump; ToF Result: (2) L case(239 MeV): completecoverage cmsframe: cos(q)= 0 symmetric Jackson-frames helicity-frames
N*ews from COSY – pp pK+ (L;S0) Reaction: pp p K+ (p p-) 3 beam energies: pp = 2.95 GeV/c (QL = 204, QS = 124 MeV); 3.06 GeV/c (239, 162 MeV); 3.20 GeV/c (284, 207 MeV) Primary andsecondary V-shape; chargedmultiplicity jump; ToF Result: (3) helicity-frames: strong evidencefor: N*(1650)S11 N*(1710)P11and/or N*(1720)P13 unlikely: N*(1675)D15 N*(1680)F15 N*(1700)D13 pL K+p
N*ews from COSY – pp pK+ (L;S0) Reaction: pp p K+ (p p-) 3 beam energies: pp = 2.95 GeV/c (QL = 204 MeV); 3.20 GeV/c (284 MeV) 3.30 GeV/c (316 MeV) Primary and secondary V-shape; charged multiplicity jump; ToF Result: (3)COSY-TOF collaboration, PL B 688, 142 (2010) Dalitz-plot analysis Importance of N*(1650) compared to N*(1710) N*(1720) 2.85 GeV/c … TOF (2006)
N*ews from COSY – pp pK+ (L;S0) Reaction: pp p K+ (p p-) 3 beam energies: pp = 2.95 GeV/c (QL = 204, QS = 124 MeV); 3.06 GeV/c (239, 162 MeV); 3.20 GeV/c (284, 207 MeV) Primary andsecondary V-shape; chargedmultiplicity jump; ToF Result: (4) S0case(162 MeV): completecoverage smallstatistics cmsframe Jackson-frames helicity-frames differencestoL
N*ews from COSY – pp pK+ (L;S0) • Next: additional high-statisticsdata PWA • (i) upgradeddetector (STT)(ii) polarizedprotonbeam (2.95 GeV/c) pb = 2.95 GeV/c P = (61 +- 2) %
N*ews from COSY – pp pK+ (L;S0) • Next: additional high-statisticsdata PWA • (i) upgradeddetector (STT)(ii) polarizedprotonbeam (2.95 GeV/c) • PAC39 (May 2011) allocated 9 weekstofinalizephysicsprogram; • after thatTOF will bedecomissioned in 2012. pb = 2.95 GeV/c P = (61 +- 2) %
N*ews from COSY – Results (II) p p n K+S+ ANKE, COSY-11 HIRES
N*ews from COSY – pp n K+ S+ Reaction: pp K+ n X (COSY-11) pp K+ X ; (K+p) X ; (K+p+) X (ANKE) pp K+ X (HIRES) Result: (1)COSY-11 collaboration, PL B 643, 251 (2006) ANKE collaboration, PR C81, 045208 (2010) HIRES collaboration, PL B 692, 10 (2011) Disappointingexpt´lsituation, but: very high X-section clearlyexcluded noD* ++ (1620) contributionneeded s [µb]
N*ews from COSY – Results (III) p p p pw (Resonances?) TOF
N*ews from COSY – pp pp w Reaction: pp p p p+p- X 3 beam energies: pp = 2.95 GeV/c (Qw = 92 MeV); 3.06 GeV/c (128 MeV) 3.20 GeV/c (173 MeV) 4 charged particles; ToF; missing p0 Result: (1)COSY-TOF collaboration, EPJ A 44, 7 (2010) w via missing mass „… no obvious indication of w- production via N* resonances found …“
N*ews from COSY – Results (IV) p p {pp}sg (D(1232)) ANKE
N*ews from COSY – pp {pp}sg Reaction: pp pp X (X = g, p0) 6 beam energies: Tp= 353 … 800 MeV 2 protons, DEpp < 3MeV 1S0 (Diproton); qlab < 20° Result: (1)ANKE collaboration, J.Phys. G 37, 105005 (2010) missingmassanalysis p0 dominating; clearg-contribution
N*ews from COSY – pp {pp}sg Reaction: pp pp X (X = g, p0) 6 beam energies: Tp = 353 … 800 MeV 2 protons, DEpp < 3MeV 1S0 (Diproton); qlab < 20° Result: (2) energy dependence shows resonant behavior; comparison with pn d g D-resonance shifted, smaller width (note: no M1 possible) WASA/Promise result (Uppsala) – covers much larger angular range
N*ews from COSY – Results (V) p n d p0p0 (ABC-Effect) WASA May 18,2011 - Session II-C (15:20) T. Tolba; „Double pion production in pp-interactions at Tp = 1.4 GeV“
N*ews from COSY – pp pp p0p0 near threshold high energies pp→∆ ∆(1232) p π p π pp ppππ pp→pN*(1440) p π π ∆ (1232) π p π
N*ews from COSY – pn d p0p0 Reaction: pd d p0p0 pspectator ; d andp0p0detected 3 beam energies: Tp = 1.0, 1.2, 1.4 GeV; Fermi momentum Effective energy ranges: 2.22 – 2.36; 2.33 – 2.44; 2.42 – 2.56 GeV Result: (1) WASA-Collaboration, submitted PRL (2011)
N*ews from COSY – pn d p0p0 Reaction: pd d p0p0 pspectator ; d and p0p0 detected 3 beam energies: Tp = 1.0, 1.2, 1.4 GeV; Fermi momentum Effective energy ranges: 2.22 – 2.36; 2.33 – 2.44; 2.42 – 2.56 GeV Result: (2) Maximum (2.38 GeV) Off-peak (2.50 GeV)
N*ews from COSY – pn d p0p0 Reaction: pd d p0p0 pspectator ; d and p0p0 detected 3 beam energies: Tp = 1.0, 1.2, 1.4 GeV; Fermi momentum Effective energy ranges: 2.22 – 2.36; 2.33 – 2.44; 2.42 – 2.56 GeV Result: (2)
N*ews from COSY – pn d p0p0 Reaction: pd d p0p0 pspectator ; d and p0p0 detected 3 beam energies: Tp = 1.0, 1.2, 1.4 GeV; Fermi momentum Effective energy ranges: 2.22 – 2.36; 2.33 – 2.44; 2.42 – 2.56 GeV Result: (3) What is this? independently normalized Mass ~ M(DD) - 80 MeV Width ~ ¼ ofG(DD)
N*ews from COSY – pn d p0p0 Reaction: pd d p0p0pspectator ; d andp0p0detected 3 beam energies: Tp = 1.0, 1.2, 1.4 GeV; Fermi momentum Effectiveenergyranges: 2.22 – 2.36; 2.33 – 2.44; 2.42 – 2.56 GeV Result: (3) Roper-contribution(R Dp Npp)
N*ews from COSY – pn d p0p0 Reaction: pd d p0p0 pspectator ; d and p0p0 detected 3 beam energies: Tp = 1.0, 1.2, 1.4 GeV; Fermi momentum Effective energy ranges: 2.22 – 2.36; 2.33 – 2.44; 2.42 – 2.56 GeV Result: (3) t-channel DD-contribution (from pp d p+p0 via isospin)
N*ews from COSY – pn d p0p0 Reaction: pd d p0p0 pspectator ; d and p0p0 detected 3 beam energies: Tp = 1.0, 1.2, 1.4 GeV; Fermi momentum Effective energy ranges: 2.22 – 2.36; 2.33 – 2.44; 2.42 – 2.56 GeV Result: (3) s-channel resonance at M = 2.37 GeV and G = 68 MeV
N*ews from COSY – pn d p0p0 Reaction: pd d p0p0 pspectator ; d and p0p0 detected 3 beam energies: Tp = 1.0, 1.2, 1.4 GeV; Fermi momentum Effective energy ranges: 2.22 – 2.36; 2.33 – 2.44; 2.42 – 2.56 GeV Result: (4) Next: (i) pn pn p0p0, (ii) pol. d-beam (i.e. np d p0p0), (iii) pn elastic pn R(3+) DD dp0p0 J=3 J=1
N*ews from COSY – Summary • Part oftheongoingCOSYprogramdevotedtoN* physics • (NN- and NY-interaction (ANKE, TOF), symmetries (WASA), …) • Hyperon productionat TOF extensionto pol. beams PWA • ABC-resonanceat WASA nature (s-channelresonance?)
N*ews from COSY – Summary • Part oftheongoingCOSYprogramdevotedtoN* physics • (NN- and NY-interaction (ANKE, TOF), symmetries (WASA), …) • Hyperon productionat TOF extensionto pol. beams PWA • ABC-resonanceat WASA nature (s-channelresonance?)
N*ews from COSY – Information pp pp m