Mitglied der Helmholtz-Gemeinschaft Physics at COSY-Jülich December 2010 | Hans Ströher (Forschungszentrum Jülich, Univ. Cologne) Baryons´10, Osaka (Japan), December 7-11, 2010

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 2 Cooler and storage ring for (polarized) protons and deuterons p = 0.3 – 3.7 GeV/c Phase space cooled internal & extracted beams Injector cyclotron COSY COSY – COoler SYnchrotron … the machine for hadron spin physics

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 3 ANKE TOF WASA COSY – Experimental Facilities Hadron physics with hadronic probes Experimental set-ups:  ANKE  WASA  EDM  TOF NEW:  PAX PAX EDM … the machine for hadron spin physics

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 4 Recent results: Nucleon-nucleon program Di-proton final states  S. Dymov (Friday, Dec. 10) Strangeness program  und  (+,0,-) production Symmetries program  0, ,  ´ decays  S. Schadmand (Friday, Dec. 10) ABC effect Nuclear program  production Polarized (Anti-)protons Spin transfer Spin filtering (at COSY, AD/CERN) Future Plans: Electric Dipole Moment (EDM) search Overview

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 5 Di-proton: {pp} in 1 S 0 state (E pp < 3 MeV) (i)Inverse photodisintegration: pp  {pp} s  (ii)Deuteron breakup: dp  {pp} s n (polarized beam) (iii)Deuteron breakup: dp  {pp} s  0 (polarized beam) (iv)Pion production: pN  {pp} s  (polarized beam and target) (v)Deuteron breakup: dp  {pp} s n (polarized beam and target) Recent Results – Di-protons (ANKE)   New!   New! LEC

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 6 Recent Results – Strangeness (ANKE) Hyperon production in nucleon-nucleon collisions (i)  production:pp  K + p  (ii)  0 production:pp  K + p  0 (iii) Y  production:pp  K + p  (1405)/  0 (1385) (iv)  + production:pp  K + n  + (v)  - production:pn  K + p  -    Eur. Phys. J. A 46 (2010) Phys. Rev. C 81 (2010)  (  b) New!

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 7 Recent Results – Nuclear (ANKE) Nuclear  -production: p A   X  (K + K - ) X  Transparency ratio R  mass dependence: A ( )  Momentum dependence of R  Models indicate in-medium  -width an order-of-magnitude larger than free  Phys. Lett. B (2010) in print R New! = 1.1 GeV/c Model-dependent analyses (Paryev; Oset et al.) New!

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 8 Symmetry in  0,  and  ´decays: (i)Isospin symmetry   3  (ii)Box anomaly    +  -  (iii)Transition form factor   e + e -  and e + e - e + e - (iv)CPV   e + e -  +  - (v)Standard Model  0  e + e - Recent Results – Symmetries (WASA) Phys. Lett. B 677 (2009) New!

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 9 ABC-effect (-puzzle):  low 2  -mass enhancement in isoscalar channel  connected with isoscalar NN-pair  correlated with  excitation ?  pn  d  0  0 ; dd    0  Resonant structure: What is it? … also have data on pd, dd  3 He  n, pp  {pp} s , pd  pd  Recent Results – ABC (WASA) New!

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 10 Recent Results – Polarization (PAX) How to produce a beam of polarized anti-protons ?  Test of spin-flip (spin transfer lepton  hadron)  COSY experiment: depolarization of a polarized proton beam by unpolarized electrons (of detuned e-cooler)  cross section much too small to provide a viable tool for polarizing anti-protons  method of choice: spin-filtering  < 10 7 b !! Phys. Lett. B 674 (2009) 99 (90)% CL

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 11 PAX Plans – Polarized Antiprotons (PAX) Spin-filtering: repeated interaction of the beam with a polarized target „low-ß section“ Protons (FILTEX  COSY), anti-protons (CERN/AD) ANKE ABS, BRP

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 12 Cooler and storage ring for (polarized) protons and deuterons p = 0.3 – 3.7 GeV/c Phase space cooled internal & extracted beams Injector cyclotron COSY COSY – COoler SYnchrotron … an ideal starting point for a srEDM search

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 13 Future plans – EDM Upper limits for eEDM, µEDM, nEDM, …; new measurements … NEW: Search for hadronic EDMs of charged particles (p, d, 3 He) with polarized beams in a storage ring Why another EDM-experiment ? New approach Potentially highly competitive sensitivity (< e cm) Neutron and proton: complementarity (CQM) d n = 4/3 d d – 1/3 d u d p = 4/3 d u – 1/3 d d (If finite d n was found  what is d p ?) Deuteron is more than proton and neutron d d = d n + d p + d  NN

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 14 EDM at COSY – Method (I) Spin precession in an electromagnetic field Particles in storage ring with spin along momentum (frozen spin)  Observation of a transversal spin- component in a radial E-field ( d x E ): Impuls Spin

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 15 EDM at COSY – Method (II) Proton: (a = 1.79) B = 0: „Magic“ momentum:  purely electrostatic ring !

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 16 EDM at COSY – Method (II) Proton: (a = 1.79) magic momentum: p p = GeV/c no magnetic field:B V = 0 T radial E-field:E R ~ 17 MV/m ring bending radius :R B ~ 25 m  BNL proposal:two beams, (approved)simultaneously rotating in the same radial electric field: cw and ccw ring circumference: ~ 240 m Courtesy: Storage Ring EDM Collaboration

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 17 EDM at COSY – Method (III) Deuteron: (a = ) No „magic“ momentum!  combination of a dipole B-Feld and a radial E-Feld such, that the increased orbit compensates the trailing spin relative to the momentum:

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 18 EDM at COSY – Options  the size of such a ring would be larger than COSY !  the size of such a ring would be similar to COSY Magic pEDM Ring with R B = 25 m No magic pEDM 1. 2.

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 19 EDM at COSY – Options  the size of such a ring would easily fit into center of COSY 3.

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 20 EDM at COSY – Options  size of ring fits into center of COSY or into existing building Furthermore: use COSY as injector and cooler 3.

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 21 EDM at COSY – Precursor Experiment First idea: use COSY-ring with a Sibirian Snake: Sibirian Snake: Spin alignment along momentum direction in opposite ring section 1) RF fields in-front-of and behind the snake generate M = d p x E 2) Change of RF per turn changes stable spin axis by 2  3) A large number of turns leads to a (non-) observable loss of beam polarisation  (upper limit for) pEDM BUT: non-competitive level Sibirian Snake RF Snake RF

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 22 EDM at COSY – Workshop

7. Dezember 2015 Institut für Kernphysik (IKP) Folie 23 COSY-Jülich … has an exciting symmetries and spin physics program … prepares for ways to produce polarized antiproton beams … provides test beams for FAIR/HESR/PANDA … is the place for a (p,d 3 He)-EDM search Thank you for your attention ! Summary