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Pionic Deuterium. | Thomas Strauch for the Pionic Hydrogen collaboration. Experimental program of the Pionic Hydrogen collaboration. Pionic Hydrogen R-98.01 ECRIT (response function) Muonic Hydrogen Pionic Deuterium R-06.03. Exotic atoms. Bohr radius:.
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Pionic Deuterium | Thomas Strauch for the Pionic Hydrogen collaboration
Experimental program of the Pionic Hydrogen collaboration • Pionic Hydrogen R-98.01 • ECRIT (response function) • Muonic Hydrogen • Pionic Deuterium R-06.03
Exotic atoms Bohr radius:
Atomic cascade of pionic deuterium • Hadronic interaction • shift ε1s ≈ - 2,5 eV • width Γ1s ≈ 1,2 eV • Aim: • 1s /1s 1s /1s • 3% ~ 1% 12% ~ 4% D(3p - 1s) 3 keV Deser:
Pionic Deuterium Width Γ1s~ Im aπD directly related to pionproduction at threshold charge symmetry detailed-balance threshold parameter α (s-wave production)
Pion-Nucleon Interaction • Isospin 1/2 or 3/2 system • At threshold: two parameters: • s-wave scattering lengths a1/2und a3/2 • choose isoscalar und isovector scattering lengths a+ und a- :
Pionic Hydrogen • 1s : • 1s : Pionic Deuterium • 1s : + NLO(~LO) NLO: a- appears + NLO(%)
N isospin scattering lengths bandwidth mainly by LEC f1 bandwidth mainly by LEC f1 J.Gasser et al.: Hadronic atoms in QCD+QED Physics Reports 456(2008)167-251 Pionic Deuterium: bandwidth mainly by experiment Constraint for N isospin scattering lengths a & a –
Experimental setup High-resolution Bragg crystal-spectrometer Bragg law:
Experimental setup spherically bent Bragg crystal bending radius ~ 3m large area detector 6 CCDs with 600x600 pixel pixelsize 40x40 µm cyclotron trap superconducting magnets cryogenic target N. Nelms et al., Nucl. Instr. Meth 484 (2002) 419 L. M. Simons, Hyperfine Interactions 81 (1993) 253
Experimental setup Precision measurement: → low background → concrete shielding
Measurement Hit pattern on CCD detector ADC-spectrum Hit pattern after curvature correction Cluster analysis
Measurement Spectrum after cluster analysis, ADC cuts, curvature correction, projection onto x-axis rate: ≈ 30/h • high-statistics measurement • of πD(3p-1s) earlier measurement without concrete with concrete
Molecular formation • (d)nl + D2 → [(dd)d]ee • radiative deexcitation out of these formations would falsify the extracted shift ε1s • → density dependence • not seen in H, but predicted to be larger in D
Energy calibration reflection in 1st order Ga K19257.67 0.066 eV K29224.84 0.027 eV reflection in 3rd order Deslattes et al.: X-ray transition energies, Rev. of Mod. Phys., Vol 75, Jan 2003
stability with Ga Kα2 whole measure-time : 4 weeks ΔE ≈ ±2,5 meV
Results | transition energies • corrections: • e.g. index of refraction (3keV / 9keV) • crystal bending • penetration depth… no evidence for radiative de-excitation out of molecular formations ε1s = Eexp. - EQED EQED = 3077.909±0.008 eV P.Indelicato private communication
Results | shift ε1s ±0.002 QED calculation ±0.007 pionmass dominant
Extraction of the hadronic width from the line shape spectrometer response-function Doppler- broadening Lorentzfunction of transition
Spectrometer response function (RF) • RF = Rocking curve Geometry add. Gauss Energy resolution: ΔE = 436 ± 3 meV ECRIT- measurement with He-likeAr
Doppler broadening • energy release of Coulomb transitions converted into kinetic energy of the πD-atoms prediction cascade-theory, scaled from πH
Doppler broadening • kinetic energy distribution:approximation by „boxes“ prediction cascade-theory, scaled from πH
χ2 analysis • free fit one box two boxes low energy box essential no evidence for high energy contribution
Statistical studies | MC-simulations intensity input of high energy contribution: 10% : red 25% : blue probability to miss a simulated contribution
Results | Width Γ1s • →only one Low-energy-component identified, • no high-energetic parts • →numerous MC-simulations to determine systematic errors
1s = - 2325 31 meV ( ±3% → ±1,3%) • 1s = 1171 meV (±12% → %) Pionic Deuterium | Final results + 23 - 49 + 2,1 - 4,2
+5 -11 α = 252 μb threshold parameter α χPT: expected uncertainty 30% → 5% NNLO calculations
Thank you for your attention! • Debrecen – Coimbra – Ioannina – Jülich – Paris – PSI – Vienna • PSI experiments R-98.01 and R-06.03 • D. F. Anagnostopoulos, S. Biri, D. D. S. Covita, H. Gorke, D. Gotta, A. Gruber, M. Hennebach, • A. Hirtl, P. Indelicato, T. Ishiwatari, Th. Jensen, E.-O. Le Bigot, J. Marton, M. Nekipelov, • J. M. F. dos Santos, S. Schlesser, Ph. Schmid, L. M. Simons, Th. Strauch, M. Trassinelli, • J. F. C. A. Veloso, J. Zmeskal PIONIC HYDROGEN collaboration
Pionisches Deuterium • Appendix
Pionic Deuterium • 1sPionproduktion an der Schwelle NN NN Panofsky Rate: Pd = 2.83±0.04 Atom: und über optisches Theorem mit Wirkungsquerschnitt verknüpft Ladungssymmetrie Zeitumkehr-Invarianz Pionproduktion Parametrisierung:
long range stability results analysis inclination sensor data evolution of crystal temperature
Spectrometer responsefunction Electron Cyclotron Resonance Ion Trap ( ECRIT ) ECRIT= cyclotron trap (4) + hexapole magnet (2) + high frquency (5) 6.4 GHz 450 W D. Hitz et al., Rev. Sci. Instr., 71 (2000) 1116 • He-like atoms • narrow X-rays, few keV • high rate • S H(2p-1s) • Cl H(3p-1s) • Ar H(4p-1s) • D(3p-1s) CCD detector D.F.Anagnostopoulos et al., Nucl. Instr. Meth. B 205 (2003) 9 D.F.Anagnostopoulos et al., Nucl. Instr. Meth. A 545 (2005) 217
charge symmetry detailled balance D atom production extrapolation to threshold J. Hüfner, Phys. Rep. 21 (1975) 1 Appendices | NN threshold parameter PT at present/ 30% few % NLO [b] LO V. Lensky et al., nucl-th/0511054,2005
+ Coulomb corrections Formulae D U.-G. Meißner, U. Raha, A. Rusetsky, Phys. Lett.B 639 (2006) 478
d fromD 1s fromH 1s D wave function Deser formula + Coulomb corrections Single + multiple scattering