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PIONIC HYDROGEN

PIONIC HYDROGEN. D. Gotta, IKP, FZ Jülich for the PIONIC HYDROGEN collaboration Debrecen – Coimbra – Ioannina – Jülich – Paris – PSI – Vienna. goal of the measurements experimental approach and challenge strong-interaction shift  1s and width  1s.

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PIONIC HYDROGEN

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  1. PIONIC HYDROGEN D. Gotta, IKP, FZ Jülich for the PIONIC HYDROGEN collaboration Debrecen– Coimbra – Ioannina – Jülich – Paris – PSI – Vienna • goal of the measurements • experimental approach and challenge • strong-interaction shift 1s and width 1s CSB 2005 Trento - 15. 6. 2005

  2. PIONIC HYDROGEN - N scattering at „rest“ ATOMIC CASCADE 2 isospin scattering length a= a-p-p a+p+p isospin invariance: mu = md a-p-p + a+p+p = - 2 a-pon 1sa -p  -p a ++a – 1s(1+1/P)(a -p  o n)2 (1+1/P)(a –) 2 PANOFSKY ratio P –p on/ –p n = 1.546  0.009 J. Spuller et al., Phys. Lett. 67 B (1977) 479 EK = 2.5 keV strong interaction observable as shift and broadening  1s+ 7 eV attractive 1s1 eV

  3. N isospin scattering lengthsa &a – N coupling constant N sigma term N GOAL 1s /1s  0.2%&1s /1s  1-2%

  4. N sigma-term N Goldberger- Miyazawa-Oehme (GMO) sum rule  1%     current algebra Weinberg,Tomozawa: chiral limit mquark 0 Goldberger-Treiman relation N coupling constant fN Sigma term  

  5. EXPERIMENT

  6. ultimate energy resolution spherically bent Bragg crystal position & energy resolution  background reduction byanalysis of hit pattern high stop density  high X - ray line yields  bright X - ray source

  7. SET-UP at PSI cyclotron trap II more muons X-ray tube cryogenic target 0 – 40 stp H2 crystal spectrometer spherically bent crystals CCD X-ray detector  2  3 matrix 75  50 mm2

  8. DEGRADERS andCRYOGENIC TARGETinsideCYCLOTRON TRAPsuper-conducting split coil magnet  beam  109/s   = 26 ns   stop efficiency fstop  density  1% @ stp  X - rays

  9. Spherically curved Bragg crystalradius of curvature 3 m crystal cuts used Si 111 Si 110 quartz 10-1 to be used quartz 1-20 100 mm 

  10. Large - Area Focal Plane Detector 2  3 CCD 22 array with frame buffer pixel size 40 m 40 m 600  600 pixels per chip frame transfer  10 ms data processing 2.4 s operates at – 100°C  150 eV @ 4 keV X 90% cooling (LN2) storage area  flexible boards  image area N. Nelms et al., Nucl. Instr. Meth 484 (2002) 419

  11. Lorentz tails Doppler broadening  previous experiment  new experiment PEAK / BACKGROUND and FIT INTERVAL ! massive concrete shielding + large area X-ray detector PEAK-TO-BACKGROUND ratio improved by one order of magnitude !

  12. ATOMIC CASCADE andSTRONG-INTERACTION EFFECTS

  13. pnot an isolated system ! CASCADE - COLLISIONAL PROCESSES p+ H2  » dangerous effects «  • [(pp)p]ee – molecule formation („DH“) • radiative de-excitation ? • had 2.Coulomb de-excitation ! non radiative process ni nf + kinetic energy Doppler broadening had

  14. 1. MOLECULAR POTENTIALS "Vesman“ mechanism for excited states:pnl + H2[(pp) njvp] eeK experimentR. Pohl et al., Hyp. Int. 138 (2001) 35theoryS.Hara et al. I.Shinamura quenching of p 2s via [(pp)p]ee formation V.I.Korobov, … X-ray transitions from slightly shifted bound states ? consequences for H (np  1s) transitions EX EX - E? (how many) bound states below dissociation limit of 4.5 eV ? Jonsell, Froelich and Wallenius for n=1,2,3 Phys. Rev A 59 (1999) 3440 ppµ ddµ X-ray / total  0.03  1 Lindroth, Wallenius and Jonsell Phys. Rev A 68 (2003) 032502 Kilic, Karr and Hilico to be published

  15. I.1s unbiased energy determination

  16. H(3p - 1s) - density dependence H/ O energy calibration simultanuously ____________________ alternatelyH/ O mixture 4He / 16O2 / 18O2 ( 80%/10%/10%) 2 bar @ T = 86K mixture H2 / 16O2 (98%/2%) 1.2 bar @ T = 85K  4 bar  equivalent density H2  2 bar @ T = 20K  28.5 bar  equivalent density H2 1 bar @ T = 17K  LH2 first time

  17. R-98.01 Maik Hennebach, thesis Cologne 2003 1s = + 7.120  0.008  0.009 eV  0.007 eV LH2  previous experiment previous experiment – Ar K ETHZ-PSI H.-Ch.Schröder et al. Eur.Phys.J.C 1(2001)473 H(3p-1s) energyno density dependence identified EQED = ± 0.006 eV old! EQED = ± 0.001 eV new! P. Indelicato, priv. comm.

  18. II.LINE WIDTH MEASURED LINE SHAPE = RLD crystal1sDoppler broadening resolution Coulomb de-excitation ECRITHmuonic hydrogen

  19. RESPONSE FUNCTION

  20. diffraction theory XOP2 code plane crystal 387 meV similar to a Lorentzian in the tails

  21. T = 295K RESPONSE FUNCTION I EXOTIC ATOM 3500 events 3 days closest to energy of H(4p-1s)

  22. aperture  6.4 GHz, 450 W CCD detector RESPONSE FUNCTION II CRYSTAL SPECTROMETERandPSI ECRITElectron Cyclotron Resonance Ion Trapcyclotron trap (4) + hexapole magnet (2) D. Hitz et al., Rev. Sci. Instr., 71 (2000) 1116 Tion 5 eV "cold" plasma ! He-like electronic atoms  narrow X-ray transitions X = 10 - 40 meV D.F.Anagnostopoulos et al., Nucl. Instr. Meth. B 205 (2003) 9 to be publ. In Nucl. Instr. Meth. A

  23.  = 10 –8 s ECRIT measurements 2004 M1 transitionsin He-like S H(2p-1s) Cl H(3p-1s) Ar H(4p-1s) 2 3S1 1 1S0 M1 transition 30000 events in line  tails can be fixed with sufficient accuracy

  24. LINE WIDTH and INITIAL STATE ECRIT results confirm C data not corrected for Coulomb de-excitation crystal resolution subtracted previous experiment 1s< 850 meV Maik Hennebach, thesis Cologne 2003

  25. COULOMB DE-EXCITATION

  26. pnot an isolated system ! CASCADE - COLLISIONAL PROCESSES p+ H2  » dangerous effects «  • [(pp)p]ee – molecule formation („DH“) • radiative de-excitation ? • had 2.Coulomb de-excitation ! non radiative process ni nf + kinetic energy Doppler broadening had

  27. 2. COULOMB DE-EXCITATION NEUTRON - TOF(– p)ns 0 n (–H)n+H=H(–H)n-1+H+H+kinetic energy non-radiative transitions  quasi-discrete velocity profile n – TOF / ns A. Badertscher et al., Eur. Phys. Lett. 54 (2001) 313

  28. Monte-Carlo simulation µ–H (2p-1s) @ 15 bar 1.89 keV  Coulomb de-excitation   cascade model calculation (V.E. Markushin – PSI) MUONIC HYDROGEN - to quantify Coulomb de-excitation - to identify other possible cascade effects from X-ray line shape

  29. 50% of envisaged statistics Coulomb de-excitation • low-energy component • intermediate-energy component • high-energy component ----- crystal response ECRIT 2004 MUONIC HYDROGEN RUN 12/2004 analysis in progress  no satellites from molecular formation identified triplet / singlet = 3.00.2

  30. KINETIC ENERGY DISTRIBUTIONS- prediction -Jensen / Markushin at the moment of the 3p - 1s transition µH H ... 5-4 4-3 ... 5-4 4-3 experiment cascade theory HH limits "box" assumptions

  31. EXTRACTION Of THE NATURAL LINE SHAPE H(3p-1s) response function subtracted --- Doppler „boxes“  natural line width 1s - - total Coulomb de-excitation 4 - 3 good peak / background essential! 

  32. HADRONIC BROADENING

  33. ECRIT RESULTS and HADRONIC WIDTH Fit to boxes from Coulomb de-excitation and ECRIT crystal resolution subtracted previous experiment 1s  865  69 meV (7%)  H.-Ch.Schröder et al. Eur.Phys.J.C 1(2001)473 R-98.01 1s  785  27 meV preliminary

  34. PIONIC HYDROGEN - status R-98.01 PT + Panofsky previousachieved infinally exp.*1. step envisaged 1s/1s0.5%  0.2% 0.2%  2.9 % to be done final high statistics run 1s/1s7 % 3 - 4% 1-2%0.8 %

  35. PT theory SCATTERING LENGTHS f1 problem 1s [a+a – ] (1 + )   =  7.2  2.9 % J. Gasser et al.,Eur. Phys. J. C 26 (2003) 13 1s [a –(1 +  ) ] 2 = + 0.6  0.2 % P. Zemp, thesis Bern‘04 no f1 problem

  36. H- hadronic shift 1s&Ns-wave isospin scattering lengths Deser formula incl. Coulomb - strong-int. interference Trueman (1961), … 2nd order PT O(2) in  = q,  =1/137, (md-mu) LECs f1 , f2 , c1 contribute to isospin breaking in O(2) f1accuracy of prediction O(10%) V.E. Lyubovitskij & A. Rusetsky, Phys. Lett. B 494(2000)9 V.E. Lyubovitskij et al., Phys. Lett. B 520(2001)204

  37. N scattering lengths a I R-98.01 - preliminary ! corrections  = (-7.22.9)% J. Gasser et al., Eur. Phys. J. C 26 (2003) 13   = (+0.60.2)% P. Zemp, thesis University of Bern 2004

  38. N scattering lengths a II a &a – ELT phenomenological analysis + multiple scattering Ericson et al. Phy.Scr.T87(2000)71 from (H+D) multiple scattering Thomas & Landau Phys.Rep.58(1980)121 DLT PT analysis Beane et al. Nucl.Phys.A 720(2003)399 from (H+D) • correction  = -7.22.9% • J. Gasser et al., • Eur. Phys. J. C 26 (2003) 13 R-98.1   = +0.60.2% P. Zemp, thesis Bern‘04 current algebraWeinberg, Tomozawa ‘66 N phase shift KH80 - - HBPT 3rd orderFettes, Meissner, Steininger NP A640(1998)199

  39. N coupling constant Goldberger- Miyazawa-Oehme (GMO) sum rule  1% 13.21 + 0.11 - 0.05  previous H + D exp. H.-Ch. Schröder et al., Eur. Phys. J. C 21 (2001) 473 1sHa-p-p 1sDa += a-p-p + a+p+p  a-p-p + a-n-n charge symmetry  Ericson, Loiseau & ThomasPhys. Rev. C 66, 014005 (2002) shift H+D R-98.01  13.89 + 0.23 14.110.20 - 0.11

  40. PIONIC DEUTERIUM 1s/1s 1s/1s D D. Chatellard et al. (1994)  2% 12% P.Hauser et al. (1998)

  41. D- hadronic shift 1s&Ns-wave isospin scattering lengths d  p + n corrections!a - p + a - n = (a1/2+2a3/2 ) /3 = 2 a+isoscalarscatt. length Deser formula SS single scattering DS double scattering (  60% ) HC higher orders AB absorptive corrections experiments  ad= - 0.0261  0.0005 / mD. Chatellard et al., NPA 625(1997)855 P. Hauser et al., PRC 58(1998)R1869  calculations  ada Beane, Bernard, Lee, Meissner, PR 57 (1998) 424 Ericson, Loiseau & Thomas, PR C 66, 014005 (2002) Beane, Bernard, Epelbaum, Meissner, Phillips NPA 720 (2003)399 Rusetski et al., in progress ...

  42. f0 N  H –p scattering at „rest“ 1sa -p  -p a ++a – 1s(a -p  o n)2 (a –) 2 D 1sa -p  -p + a - n - n a + 0 1s>> 0 d  p + n Meissner, Raha, Rusetski, Eur. Phys. J. C41 (2005) 213 f0 problem nuclei T / 3He with ... without external pions a +,a – e. g. 4He Baru, Haidenbauer,Hanhart, Niskanen, Eur. Phys. J. A16 (2003) 437

  43. 1. MOLECULAR POTENTIALS "Vesman“ mechanism for excited states:pnl + H2[(pp) njvp] eeK experimentR. Pohl et al., Hyp. Int. 138 (2001) 35theoryS.Hara et al. I.Shinamura quenching of p 2s via [(pp)p]ee formation V.I.Korobov, … X-ray transitions from slightly shifted bound states ? consequences for H (np  1s) transitions EX EX - E? (how many) bound states below dissociation limit of 4.5 eV ? Jonsell, Froelich and Wallenius for n=1,2,3 Phys. Rev A 59 (1999) 3440 ppµ ddµ X-ray / total  0.03  1 Lindroth, Wallenius and Jonsell Phys. Rev A 68 (2003) 032502 Kilic, Karr and Hilico to be published

  44. PIONIC DEUTERIUM energy calibration I Cl K 2.62 keV 15 min response function I Ne(7-6) 2.72 keV 12 h strong interaction D(2p-1s) 2.60 keV 15 h 1s = – 2.469  0.055 eV 1s = 1.093  0.129 eV P. Hauser et al., PR C 58 (1998)R1869

  45. LIGHT PIONIC ATOMS - A = 3, 4 1s/1s 1s/1s 3HeI.Schwanner et al.(1979) 10% 25% NP A 412 (1984) 253 T------ 4HeG.Backenstoss et al.(1974) 3% 7%

  46. SUMMARY PIONIC HYDROGEN ISOTOPES - TIME" DEPENDENCE ,   2006 X-rays identified ? 2006 Increase of precision to the 1% also for A=3,4 desirable ?

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