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Christina Dimopoulou Max-Planck-Institut für Kernphysik, Heidelberg IPHE, Université de Lausanne, 26.05.2003 Exploring atomic fragmentation with COLTRIMS (Cold Target Recoil Ion Momentum Spectroscopy)
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Atomic & Molecular Break-Up - Intense femtosec laser pulses - Ion induced femtosec fields Experiment - The “Reaction-Microscope” Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields
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Momentum Spectroscopy: Principle piccolo sparkling wine champagne landing zone (detector) velocity, angle time-of-flight and landing position => initial velocity and angle i.e. initial momentum vector
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electrons position sensitive multi-hit Projectile: Cold Target: supersonic atomic jet molecules clusters Detectors: recoil ions E-field Recoil Ion Momentum Spectroscopy single photons intense lasers charged particles t; x,y,z) ~ eV B-field ~ meV Reaction Microscope
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Ion Time-of-flight Ar + Ar 2 + Ar ++ H2O+H2O+ H2+H2+ Ex. Multi-photon ionisation of Ar 0 -0.5-1.51.0 1.5 p || [a.u.] 0.5 Ar + N=12 N=13 N=11 N=14 1.8 eV detector +U o a d +U ion trajectory
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Atomic & Molecular Break-Up - Intense femtosec laser pulses - Ion induced femtosec fields Experiment - The “Reaction-Microscope” Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields
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Single Photons... Intense Laser Target Jet Laser Ion Detector Electron Detector Ti:Sa Laser photon energy: 1.5 eV (T=2.7 fs) pulse length (FWHM): 30 fs intensity: I max ~10 16 W/cm 2 repetition rate: 3 kHz
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Multi-photon Single Ionisation electrons E R = E e /M R electron Ar 1+ E e = N h - I p, N>10 P e = - P R I 10 13 W/cm 2 h = 1.56 eV P = E /c 0
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Intense Laser: Single Ionisation =30 fs E y (t) t I 10 15 W/cm 2 pulse T=2 / =2.7 fs Drift momentum 2. t t 0 = 0 t 0 = 45 t 0 = 90 E y (t) Moshammer et al. PRL 2000 tunneling P ion =-P e 0 e 1 1.
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Intense Laser : Double Ionisation sequential Larochelle et. al J. Phys. B31 (1998) Orders of magnitude difference due to e-e correlation Ne 2+ 1. 10 15 W/cm 2 E y (t) non-sequential 3. 10 15 W/cm 2 Moshammer et al. PRL 2000
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Non-sequential Double Ionisation Kuchiev 1987 Schafer et al. 1993 Ne 2+ Time delay Double peak structure E y (t)
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Atomic & Molecular Break-Up - Intense femtosec laser pulses - Ion induced femtosec fields Experiment - The “Reaction-Microscope” Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields
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Ion Induced femtosec Fields Example: Electron Capture p p i p p f He Ne 6+ Ne 7+ v P = 0.36 a.u. I 3 10 15 W/cm 2 t b/ v p 0.3 fs t t p r b~5 a.u.
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Electron Capture: Precision Spectr. Ne 6+ Ne 7+ p p p r p r|| = Q /v p -v p /2 = p r p p | v P = 0.36 a.u. He 1+ p r p p f p p i
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Electron Capture: Precision Spectr. capture into n=4 excellent resolution: 0.7eV FWHM excellent precision: 3-100 meV many states resolved simultaneously no selection rules
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Atomic & Molecular Break-Up - Intense femtosec laser pulses - Ion induced femtosec fields Experiment - The “Reaction-Microscope” Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields
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Studies with Highly Charged Ions 1.Precision Spectroscopy 2.Dynamics of formation: many-electron flux (correlated?) 3. Rearrangement processes Questions : Formation of ”hollow atoms” t ≈ 1 fs HCI from HITRAP HCI Target X-rays Auger cascades E~keV/amu Reaction-Microscope
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The HITRAP Reaction Microscope large area ion detector with hole multi-hit electron detector (up to 10 e - ) large area photon detectors Increased Acceptance and Q-Value Resolution Coincident detection of ions, electrons and photons
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Atomic & Molecular Break-Up - Intense femtosec Laser Pulses - Ion induced femtosec fields Experiment - The “Reaction-Microscope” Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields
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Laser Assisted Electron Capture Laser & ion induced fields combined p p i p p f He Ne 6+ Ne 7+ v P = 0.36 a.u. I 3 10 15 W/cm 2 t b/ v p 0.3 fs t t p r b~5 a.u. Laser I ~ 10 13 W/cm 2, ~ ns
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-03 0 0.3 Laser Assisted Electron Capture Intensity -0.3 0 0.3 10 13 W/cm 2 Ion Longitudinal Momentum Impact Parameter Ion Longitudinal Momentum p p p r p r|| = Q /v p -v p /2 = p r p p | p r p p f p p i + p drift ( t 0 )
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-03 0 0.3 Laser Assisted Electron Capture Impact Parameter Ion Longitudinal Momentum T.Kirchner PRL 2002 + p drift ( t 0 ) p p p r p r|| = Q /v p -v p /2 = p r p p | p r p p f p p i -03 0 0.3 Intensity 10 13 W/cm 2 Ion Longitudinal Momentum -0.3 0 0.3 Impact Parameter Probability
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-03 0 0.3 Laser Assisted Electron Capture Impact Parameter Ion Longitudinal Momentum Impact Parameter Probability T.Kirchner PRL 2002 p p p r p r|| = Q /v p -v p /2 = p r p p | p r + p drift ( t 0 ) p p f p p i -03 0 0.3 Intensity 10 13 W/cm 2 Ion Longitudinal Momentum -0.3 0 0.3
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Atomic & Molecular Break-Up - Intense femtosec Laser Pulses - Ion induced femtosec fields Experiment - The “Reaction-Microscope” Future - Studies with HCI : HITRAP - Laser assisted collisions - Sub-attosec ion induced fields
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Sub-attosecond Ion Induced Fields + e-e- He 2+ Heisenberg’s as microscope 1 GeV/amu U 92+ : =2, v p = 120 a.u. b=2 a.u. He 40 as + I 10 20 W/cm 2 t b/ ( v p ) =0.2 as “Instantané” of the initial two (many)-electron wave function Ex. Double ionisation of He by 100 MeV/amu C 6+ Bapat et al. JPB 2000
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Sub-attosecond Ion Induced Fields Intense relativistic HCI beams at GSI Heisenberg’s as microscope
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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 Max-Planck Institut, Heidelberg H. Rottke, C. Trump, B. Bapat E. Eremina, W. Sandner UMR, Rolla M. Schulz, R.E. Olson, D. Madison Max-Born Institut, Berlin Navrangpura, India GSI, Darmstadt S. Hagmann, R. Mann
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Electron Capture: Precision Spectr.
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Recoil Ion Momentum Spectroscopy Electron detector supersonic gas-jet drift Helmholtz coils: projectile beam electrons recoil ions E-field B-field Ion detector
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Reaction Microscope Ar + Ar 2 + Ar ++ 1 cm Ar 2 + Ar + +U o a d +U detector Ar ++
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Intense Laser: Single Ionisation =30 fs E y (t) t I 10 15 W/cm 2 pulse T=2 / =2.7 fs Drift momentum 1. 2. t t 0 = 0 t 0 = 45 t 0 = 90 E y (t) Moshammer et al. PRL 2000 Ponderomotive potential
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Rescattering: Dynamics t E y (t) y(t) e1e1 Ne 1+ e2e2 e1e1 Ne 2+ time delay t0t0
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