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Christina Dimopoulou Max-Planck-Institut f ür Kernphysik, Heidelberg

Exploring atomic fragmentation with COLTRIMS (Cold Target Re coil Ion Momentum Spectroscopy). Christina Dimopoulou Max-Planck-Institut f ür Kernphysik, Heidelberg. IPHE, Université de Lausanne, 26.05.2003. Experiment - The “Reaction-Microscope”.

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Christina Dimopoulou Max-Planck-Institut f ür Kernphysik, Heidelberg

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  1. Exploring atomic fragmentation with COLTRIMS (Cold Target Recoil Ion Momentum Spectroscopy) Christina Dimopoulou Max-Planck-Institut für Kernphysik, Heidelberg IPHE, Université de Lausanne, 26.05.2003

  2. Experiment- The “Reaction-Microscope” Atomic & Molecular Break-Up - Intense femtosec laser pulses - Ion induced femtosec fields Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields

  3. champagne sparkling wine piccolo Momentum Spectroscopy: Principle velocity, angle landing zone (detector) time-of-flight and landing position => initial velocity and angle i.e. initial momentum vector

  4. Recoil Ion Momentum Spectroscopy Reaction Microscope Cold Target: • supersonic atomic jet • molecules • clusters Detectors: • position sensitive • multi-hit Projectile: • single photons • intense lasers • charged particles electrons  ~ meV recoil ions  t;x,y,z) ~ eV E-field B-field

  5. Ion Time-of-flight 1.5 1.0 0.5 -0.5 -1.0 -1.5 0 d a p|| [a.u.] ion trajectory N=11 detector Ar+ Ar+ N=12 Ar++ N=13 Ar2+ +Uo +U 1.8 eV N=14 H2O+ H2+ Ex. Multi-photon ionisation of Ar

  6. Experiment- The “Reaction-Microscope” Atomic & Molecular Break-Up - Intense femtosec laser pulses - Ion induced femtosec fields Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields

  7. Single Photons . . . Intense Laser Target Jet Ion Detector Laser Electron Detector Ti:Sa Laser photon energy: 1.5 eV (T=2.7 fs) pulse length (FWHM): 30 fs intensity: Imax~1016 W/cm2 repetition rate: 3 kHz

  8. e I  1013 W/cm2 h = 1.56 eV P =E /c  0 electron Ee = N h - Ip , N>10 Pe = - PR Ar1+ ER = Ee/MR Multi-photon Single Ionisation electrons

  9. Ey(t) t0 = 0 t t0 = 45 tunneling P = - P 0 » t0 = 90 ion e Moshammer et al. PRL 2000 e 1 Intense Laser: Single Ionisation 2. Drift momentum pulse I 1015 W/cm2 Ey(t) T=2/=2.7 fs t  =30 fs 1.

  10. Ey(t) Ey(t) Ne2+ Ne2+ Intense Laser : Double Ionisation 3.1015 W/cm2 sequential 1.1015 W/cm2 non-sequential Moshammer et al. PRL 2000 Orders of magnitude difference due to e-e correlation Larochelle et. al J. Phys. B31 (1998)

  11. Ey(t) Ne2+ Double peak structure Time delay Non-sequential Double Ionisation Ne2+ Kuchiev 1987 Schafer et al. 1993

  12. Experiment- The “Reaction-Microscope” Atomic & Molecular Break-Up - Intense femtosec laser pulses - Ion induced femtosec fields Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields

  13. p i Ne6+ p Ne7+ f p p vP = 0.36 a.u. b~5 a.u. He t p r I 3 1015 W/cm2 t b/ vp 0.3 fs Ion Induced femtosec Fields Example: Electron Capture

  14. Ne6+ f p Ne7+ p p i p Q D p p vP = 0.36 a.u. He1+ Q |pp| p ^ r = p r = - p = Q / v - v /2 p r|| p p r Electron Capture: Precision Spectr.

  15. Electron Capture: Precision Spectr. • excellent resolution: 0.7eV FWHM • excellent precision: 3-100 meV • many states resolved simultaneously • no selection rules capture into n=4

  16. Experiment- The “Reaction-Microscope” Atomic & Molecular Break-Up - Intense femtosec laser pulses - Ion induced femtosec fields Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields

  17. Auger cascades HCI from HITRAP X-rays E~keV/amu Reaction-Microscope <~~~~~~~~~ HCI Target Studies with Highly Charged Ions t ≈ 1 fs Formation of ”hollow atoms” Questions: • Precision Spectroscopy • Dynamics of formation: • many-electron flux (correlated?) • 3. Rearrangement processes

  18. large area ion detector with hole • multi-hit electron detector (up to 10 e-) • large area photon detectors The HITRAP Reaction Microscope • Increased Acceptance and Q-Value Resolution • Coincident detection of ions, electrons and photons

  19. Experiment- The “Reaction-Microscope” Atomic & Molecular Break-Up - Intense femtosec Laser Pulses - Ion induced femtosec fields Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields

  20. p i Ne6+ p Ne7+ f p p vP = 0.36 a.u. b~5 a.u. He t p r I 3 1015 W/cm2 t b/ vp 0.3 fs Laser Assisted Electron Capture Laser & ion induced fields combined Laser I ~ 1013 W/cm2,~ ns

  21. Q D p p i p p f p p Q |pp| p ^ r = p r = - p = Q / v - v /2 p r|| p p r -0.3 0 0.3 Laser Assisted Electron Capture + pdrift (t0) 1013 W/cm2 Intensity Impact Parameter -03 0 0.3 Ion Longitudinal Momentum Ion Longitudinal Momentum

  22. Q D p p i p p f p p Q |pp| p ^ r = p r = - p = Q / v - v /2 p r|| p p r Probability Impact Parameter Laser Assisted Electron Capture + pdrift (t0) T.Kirchner PRL 2002 1013 W/cm2 Intensity Impact Parameter -03 0 0.3 -03 0 0.3 -0.3 0 0.3 Ion Longitudinal Momentum Ion Longitudinal Momentum

  23. D p p i p Q p f p p Q |pp| p ^ r + pdrift (t0) = p r = - p = Q / v - v /2 p r|| p p r Probability Impact Parameter Laser Assisted Electron Capture T.Kirchner PRL 2002 1013 W/cm2 Intensity Impact Parameter -03 0 0.3 -03 0 0.3 -0.3 0 0.3 Ion Longitudinal Momentum Ion Longitudinal Momentum

  24. Experiment- The “Reaction-Microscope” Atomic & Molecular Break-Up - Intense femtosec Laser Pulses - Ion induced femtosec fields Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields

  25. + + 1 GeV/amu U92+ : =2, vp = 120 a.u. He b=2 a.u. <Te> 40 as I 1020 W/cm2 t b/ ( vp )=0.2 as Ex. Double ionisation of He by 100 MeV/amu C6+ e- Bapat et al. JPB 2000 ~~~~~ He2+ Sub-attosecond Ion Induced Fields Heisenberg’s as microscope “Instantané” of the initial two (many)-electron wave function

  26. Intense relativistic HCI beams at GSI Sub-attosecond Ion Induced Fields Heisenberg’s as microscope

  27. Max-Planck Institut, Heidelberg • R. Moshammer, H. Kollmus, D. Fischer, B. Feuerstein, C. Höhr, • A. Dorn, C.D. Schröter, A. Rudenko, C. Dimopoulou, • K. Zrost, V. Jesus, J. R. Crespo Lopez-Urrutia, • A. Voitkiv, T. Kirchner, J. Ullrich UMR, Rolla GSI, Darmstadt S. Hagmann, R. Mann M. Schulz, R.E. Olson, D. Madison Max-Born Institut, Berlin Navrangpura, India H. Rottke, C. Trump, B. Bapat E. Eremina, W. Sandner

  28. Electron Capture: Precision Spectr.

  29. B-field E-field Helmholtz coils: electrons Ion detector drift Electron detector recoil ions projectile beam supersonic gas-jet Recoil Ion Momentum Spectroscopy

  30. Reaction Microscope d a 1 cm Ar++ detector Ar+ Ar2+ +Uo +U Ar++ Ar+ Ar2+

  31. Ey(t) Ponderomotive potential t0 = 0 t t0 = 45 t0 = 90 Moshammer et al. PRL 2000 Intense Laser: Single Ionisation 2. Drift momentum pulse I 1015 W/cm2 Ey(t) T=2/=2.7 fs t  =30 fs 1.

  32. Ne2+ Rescattering: Dynamics Ey(t) t t0 e2 y(t) e1 e1 Ne1+ Ne2+ time delay

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