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Momentum Imaging in Atomic Collision Physics

Momentum Imaging in Atomic Collision Physics. BREADTH : MICROMODEL OF ICPEAC WHAT IS IT? FOCUS: DOUBLE IONIZATION. ICPEAC 2003. BREADTH: MODEL OF ICPEAC ?. OF MOLECULES WHICH EXPLODE. WITH SYNCHROTRON RADIATION. EVENT BY EVENT MOMENTUM IMAGING ION-ATOM COLLISIONS.

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Momentum Imaging in Atomic Collision Physics

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  1. Momentum Imaging in Atomic Collision Physics • BREADTH : MICROMODEL OF ICPEAC • WHAT IS IT? • FOCUS: DOUBLE IONIZATION ICPEAC 2003

  2. BREADTH: MODEL OF ICPEAC ? OF MOLECULES WHICH EXPLODE WITH SYNCHROTRON RADIATION EVENT BY EVENT MOMENTUM IMAGING ION-ATOM COLLISIONS COLLISIONS IN MOTS USE TO ANALYZE MOT IONIZATION WITH INTENSE LASER PULSES ICPEAC 2003

  3. p’ p’ p p Conceptual COLTRIMS Projectile Electron Recoil Single detectors p p Imaging p E p B

  4. THE DETECTOR Cold Target Recoil Ion Momentum Spectroscopy The detector Well, not really, but the idea is similar CMS detector at Fermilab

  5. THE BASIC DETECTOR COILS POSITION AND TIME SENSITIVE DETECTORS E B REACTION P ALONG BEAM FROM TIME P TRANSVERSE FROM POSITION

  6. CHOOSE ONE OF EACH BEAM TARGET DETECTOR LASER BEAM COILS (SUPERSONIC) JET POSITION AND TIME SENSITIVE DETECTORS E B l/4 SYNCHROTRON RADIATION PHOTON BEAM l/4 l/4 MOT l/4 ION BEAM

  7. CLASSIC CONFIGURATION : IONS ON JETS COILS POSITION AND TIME SENSITIVE DETECTORS E B SUPERSONIC JET ION BEAM

  8. VARIATION ONE: PHOTONS ON JETS COILS POSITION AND TIME SENSITIVE DETECTORS E B SUPERSONIC JET SYNCHROTRON RADIATION PHOTON BEAM

  9. VARIATION TWO: LASERS ON JETS COILS POSITION AND TIME SENSITIVE DETECTORS E B SUPERSONIC JET LASER BEAM

  10. VARIATION THREE: ION BEAMS ON MOT COILS POSITION AND TIME SENSITIVE DETECTORS l/4 E l/4 l/4 MOT B l/4 ION BEAM

  11. VARIATION FOUR: LASER BEAMS ON MOT COILS POSITION AND TIME SENSITIVE DETECTORS l/4 E l/4 l/4 MOT B l/4 LASER BEAM

  12. Some typical momenta in the interaction Momentum carried by photon: E/c , c=137 in au. : 8 x 10 –3 a.u. for a 300 eV photon. Momentum carried by a 10 eV electron ejected from atom: 0.86 a.u. Momentum carried by 5 eV molecular C+ fragment: 90 a.u. Momentum of thermal He atom at 300 K / Rb atom at 250 x 10 -6 K 4 a.u. .017 a.u. Experimental resolution: Recoils < 0.2 a.u. Electrons < 0.05 a.u.

  13. The physics Capture by highly charged ions Capture by highly charged ions Low energy collisions: Ionization : continuum electrons High energy collisions: Large Z/v Single electron processes Small Z/v…photons Large Z/v Two electron processes Small Z/v…photons Fixed in space molecules: inner shells Intense laser

  14. Electric field caused by a passing Xe 26+ ion

  15. Q spectra for capture from He by Ar 16+ ions M.Abdallah, W.Wolff, H.E.Wolf, E.Y.Kamber,M.Stockli and C.L.Cocke, Phys.Rev.A 58, 2911(1998).

  16. Q value versus Auger electron energy in double capture O 6+ + He O 4+ (nl,n’l’) + He ++ O 5+ + e Auger O 6+ on He at 138 keV G. Laurent , M. Tarisien , X. Flechard , et al., Nucl. Inst. Meth. (2003, to be published).

  17. High resolution Q value spectra from capture by Ne 7+ from He at 0.35 a.u. pz of recoil D.Fischer, B.Feuerstein, R.D.DuBois, R.Moshammer, J.R.Crespo-Lopez-Urrutia et al., J. Phys. B 35, 1369 (2002). Momentum resolution 0.07 a.u.

  18. Q-value spectra from Ar 8+ on atomic hydrogen Experiment:Erge Edgu-Fry, Ph.D.Thesis Theory: Lee and Lin, Close coupling AO Relative populations (%) Experiment Theory 5s 8.1 8.5 5p 14.6 19.6 5dfg 29.8 43.4 Sum 5 52.5 71.6 6s 3.3 13.2 6p 32.5 6.3 6dfg 10.4 8.9 Sum 6 46.3 28.4

  19. M.Van der Poel Ph.D. thesis Orsted Institute, Univ. Copenhagen MOTRIMS Van der Poel Frauhenhofer diffraction in capture from Na by Li+ Dq ~ 10 -6 rad M. van der Poel, C. V. Nielsen, M.-A. Gearba, and N. Andersen, Phys. Rev. Lett. 87, 123201 (2001).

  20. MOTRIMS results: O 6+ on Na capture Experiment CTMC J.W. Turkstra,R. Hoekstra,S. Knoop,D. Meyer, R. Morgenstern,and R. E. Olson, Phys.Rev.Lett. 87, 123202 (2001).

  21. KSU MOTRIMS Cs+ R. Brédy, H. Nguyen, H. A. Camp, X. Flechard and B. D. DePaola, J.R.Macdonald Laboratory, Kansas State Univ.

  22. KSU MOTRIMS Na+ R. Brédy, H. Nguyen, H. A. Camp, X. Flechard and B. D. DePaola, J.R.Macdonald Laboratory, Kansas State Univ. Na+ capturing from Rb(5s) and Rb(5p) 5p-3p 5s-3p laser on laser off T. G. Lee, H. Nguyen, X. Flechard, B. D. DePaola, and C. D. Lin Phys. Rev. A 66, 042701 (2002)   

  23. The physics Capture by highly charged ions Low energy collisions: Ionization : continuum electrons Ionization: continuum electrons High energy collisions: Large Z/v Single electron processes Small Z/v…photons Large Z/v Two electron processes Small Z/v…photons Fixed in space molecules: inner shells Intense laser

  24. Continuum electrons for fixed scattering plane Doerner et al, Phys.Rev.Lett. 77, 4520 (1997) 5 keV Projectile 10 keV Recoil 15 keV In plane p on He

  25. Electron spectra for He+ on He 1 eV e He+ He+ M.A.Abdallah et al., Phys.Rev.81, 3627 (1998).

  26. Electron spectra for Transfer Ionization for He++ on He A.F.Afaneh, R Doerner, L Schmidt, Th Weber, K E Stiebing, O Jagutzki and H Schmidt-Boecking, J. Phys. B 35 L229 (2002).

  27. The physics Capture by highly charged ions Low energy collisions: Ionization : continuum electrons High energy collisions: Large Z/v Single electron processes Single electron processes Small Z/v…photons Large Z/v Two electron processes Small Z/v…photons Fixed in space molecules: inner shells Intense laser

  28. Electron ejection by charged particle: large q vs small q V~ e iq.r Small q………. “optical limit” Large impact parameter Projectile delivers energy only Sets positive charge in Oscillation against negative charge Large q exchange with one electron Rest of atom is spectator (Rutherford and Marsden)

  29. Single photoionization recoils 80 eV Single Ionization of He R. Doerner et al., Phys. Rev. Lett. 76, 2654 (1996). hn krecoil ion = -ke

  30. Very low perturbation He single ionization:electron – recoil momentum balance 1 GeV/u U 92+on He Moshammer et al., Phys.Rev.Lett. 79, 3621 (1997).

  31. Kinematically complete: electron spectra for experimentally controlled q Photons Charged particles q e e- He+ “recoil” q “binary” 3 keV electrons q=1.5 a.u. 100 MeV/u C 6+ q=.88 a.u. A.Dorn, R.Moshammer, C.D.Schroeter, et al., Phys.Rev.Lett.82,2496(1999). M.Schulz, R.Moshammer, D.H.Madison, R.E.Olson et al., J.Phys.B 34, L305 (2001).

  32. Is everything understood for single ionization in the low perturbation limit? 100 MeV/u C 6+ on He Single ionization electron momentum distributions Experiment M.Schulz et al., Nature 422, 48 (2003) Calculation (Madison) Conclusion: nuclear momentum transfer not being treated correctly.

  33. High perturbation He single ionization:electron-recoil momentum balance 3.6 Mev/m Se 28+ on He Moshammer et al., Phys.Rev.A 56, 1351 (1997).

  34. The physics Capture by highly charged ions Low energy collisions: Ionization : continuum electrons High energy collisions: Large Z/v Single electron processes Small Z/v…photons Large Z/v Two electron processes Two electron processes Small Z/v…photons Fixed in space molecules: inner shells Intense laser

  35. Two electron removal: how to do it? TS2 TS1 L.H.Andersen, H.Knudsen, P.Hvelplund, et al., Phys.Rev.Lett. 57, 2147 (1986).

  36. q He++ ee High perturbation He double ionization: electron pair –recoil momentum balance Double ionization: Electron pair ejection 3.6 MeV/u Au 53+ on He A.N.Perumal, R.Moshammer,M.Schulz and J.Ullrich, J.Phys.B 35, 2133 (2002). Single ionization 3.6 Mev/m Se 28+on HeMoshammer et al.,Phys.Rev.A 56, 1351 (1997).

  37. The small perturbation case Shakeoff TS1 collision Small Z/v or photon

  38. Electron distributions: photodouble ionization of He e k+ = k1+k2 k- =(k1-k2)/2 E1 selections rules DA=0 implies electrons in p state J S Briggs and V Schmidt, J.Phys.B 33, R1 (2000). k1 k- k+ Jacobi k2 Lab E1 selection rules plus ee repulsion;No back to back, no parallel emission Opening angle around 120 degrees k1,k2 e

  39. Photodouble ionization of He 1 eV 20 eV excess energy k+ = k1+k2 e k1, k2 Electron momenta k- = (k1-k2)/2 H. Braeuning, R. Doerner, C.L. Cocke, M.H. Prior et al., J. Phys. B30, L649 (1997).

  40. Can we get out of the “collective motion” region into the “single particle motion” region? A.Knapp, M.Walter, Th. Weber, A.L.Landers, et al., .Phys.B L521 (2002).

  41. The “shaken off” electron Photodouble ionization at 529 eV photon energy slow fast Soft electrons are shaken off e 2eV Harder electrons are generated in ee collisions 30eV Experiment Theory (CCC:Kheifets) A.Knapp, A.Kheifets, I.Bray, Th.Weber, A.L.Landers et al., Phys.Rev.Lett.89, 033004 (2002).

  42. Photodouble ionization of H2: the relaxation of the dipole selection rule Walter and Briggs, PRL 85, 1630 (2000). Node on cone where no dipole moment of system along polarization vector e H2: Node is There but relaxed Thorsten Weber ,Ph.D. thesis, Univ. Frankfurt (2003) and Th. Weber et al., in preparation (2003) . Helium: Node on cone

  43. Photodouble ionization at 529 eV photon energy Soft electrons are shaken off The “shaken off” electron Experiment Theory (Kheifets) A.Knapp, A.Kheifets, I.Bray, Th.Weber, A.L.Landers et al., hys.Rev.Lett.89, 033004 (2002).

  44. Shaken electron distribution from transfer ionization 300 keV protons on He: capture one, other leaves H. Schmidt-Böcking, V. Mergel, R. Dörner et al., Europhys. Lett., 62 , 477 (2003) .

  45. Correlated “Shakeoff” Shi and Lin The probability for ionization The momentum of the shaken electron T.Y.Shi and C.D.Lin, Phys.Rev.Lett. 89, 163202 (2002).

  46. High velocity TI: CRYRING recoil pz fast protons on He , capture one, make He++ H.T. Schmidt, A. Fardi, R. Schuch, et al., Phys. Rev. Lett., 89, 163201-3 (2002) and Henning Schmidt, private comm. 2003

  47. Charged particle “dipole” double ionization q He++ e k+ =k1+k2 ee k- =(k1-k2)/2 Lab k1,k2 e Photons Charged particles q “binary” “recoil” Jacobi “binary” “recoil”

  48. Electron distributions: double ionization of He DATA 2 keV electrons q2 “binary” Experiment q “recoil” q=0.6a.u. q1 CCC Kheifets q2 q1 Photodouble ionization A. Dorn, A.Kheifets, C.D.Schroeter, B.Jajjari et al., Phys.Rev.Lett.86, 3755(2001

  49. The physics Capture by highly charged ions Low energy collisions: Ionization : continuum electrons High energy collisions: Large Z/v Single electron processes Small Z/v…photons Large Z/v Two electron processes Small Z/v…photons Fixed in space molecules: inner shells Fixed in space molecules: Inner shells Intense laser

  50. Illuminating molecules from within University Frankfurt: Reinhard Dörner,Horst Schmidt-Böcking,Thorsten Weber,Alexandra Knapp,Till Jahnke, Lothar, Schmidt, Sven Schössler, Harald Bräuning, Achim Czasch Kansas State University C. Lewis Cocke, Timur Osipov, Ali Alnaser LBNLMichael H. Prior, Jürgen Rösch, Andre Staudte Western Michigan U.Allen Landers Guest: Amine Cassimi (Ganil/Ciril) hv + CO  CO+ (1s-1) + e-(photoelectron) (few eV) (10 –17 s) CO 2+ + e-(Auger) (high energy) (10 –14 s)  C+ + O + (10 –13 s)

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