Theo J.M. Zouros Department of Physics University of Crete - Heraklion

1. High resolution Augerprojectile e- spectroscopy: A state-selective tool to study highly charged ion - atom collisions Theo J.M. Zouros Department of Physics University of Crete - Heraklion LIBRA kick-off meeting Demokritos March 11, 2009

2. Ion – Atom/electron Collisions t = -∞ ∆t = 10-17 s t = -∞ Preparation Interaction Relaxation Ionization Excitation Transfer combinations e- Non radiative: Auger electrons Radiative: Photon decay Atom/Molecule Target q = 0 (neutral) Gas/Solid gs or excited state n ~ 1012-1020 #/cm3 e- e- beam Target q = -1 I ~ 1-50 μA n ~ 106-108 #/cm3 γ e- Ion beam Z ~ 1-12 I ~ 1-100 nA q ~ 1-12 E ~ 0.5-2 MeV/u V ~ 3-6 a.u. gs or metastable Detectors projectile, recoil, photon, electron coincidences ΔΩ – solid angle ε - efficiency Black box?! γ

3. UoC HEMISPHERICAL ANALYZER WITH 2-D PSD 0o ELECTRON SPECTROMETER Faraday Cup Ion Beam 4-element lens Inner hemisphere Gas Cell Pressure Gauge Gas in electrons PSD X-Position Y- Position Timing Outer hemisphere e- θ Resolution ~ 0.1% ΔΩ = 1.8 x 10-4 sr 00 dgrs Ion

4. Experimental Setup at the 7MV tandem of J R Macdonald Laboratory – Kansas State university 1997 Dedicated experimental setup 1990 – 2007 Now have moved all to Demokritos Tandem 2003

5. Demokritos 13, 2003

6. High resolution ion Auger electron spectra E.P. Benis – PhD thesis, UoC 2001

7. Elastic Scattering of Quasi-free Electrons on B4+ Ions Doubly Excited states Zouros, Benis, Gorczyca, PRA68, 010701(R) (2003)

8. ----- 2s2p 3P ----- 2s2p 1P Elastic Scattering of Quasi-free Electrons on B3+ Ions Doubly Excited states Zouros, Benis, Gorczyca, PRA68, 010701(R) (2003)

9. Ion-atom/electron interactions: Investigation of the Coulomb force • Force is Coulomb: • Potential usually known - can write down a Hamiltonian • Calculate emission or interaction cross sections • Difficulties: many particles, long range force, correlation effects • Model calculations • Develop theoretical and experimental techniques • Test approximations

10. Interest in ion-electron/atom collisions Applications • Tokomak and AstrophysicalPlasmas • Accelerator technology - Storage rings • Radiation damage – cancer therapy • Basic atomic collisions • Use HCI and simple targets – few-electron systems • Study ion excitation rather than target excitation: • Control charge state q of ion –Nnumber of electrons • Isoelectronic sequence study – same N different Z In preparation for PHYSICS REPORTS Zero-degree Auger spectroscopy of Projectile Ions in atomic collisions in collaboration with N. Stolterfoht (HMI-Berlin)

11. Dept. of Physics, University of Crete-Heraklion, Crete Theo J.M. Zouros (Θεόδωρος Τζούρος - tzouros@physics.uoc.gr) Project: Investigation of one- and two-electron processes in energetic ion-atom collisions using high resolution Auger projectile electron spectroscopy Goal:State-selective cross section measurements of basic atomic collision processes and the investigation of their collisional energy dependence. Processes include capture, excitation, ionization and combinations such as transfer-excitation, transfer-loss, double-electron capture etc. Investigation of dynamic electron correlation effects. Scientific domain:Atomic collision physics (Basic Research) Beams: p, Li, B, Be, C, N, O, F and possibly higher Z Charge-states: bare, one-, two-, three- and four electron ions, i.e. F6-9+ etc. Intensities: 10 nA Setup: installed at INP permanently, modifications necessary. Spectrometer: Electrostatic energy analyzer in magnetically shielded chamber. Detectors: MCP or channeltron Targets: differential pumped gas target using H2, He, Ne, Ar etc. Personnel:1 Senior scientist, ideally 1 post-doc and or 1 or 2 students Man-power support by INP (Yes/No – No. of scientists – Mech. Workshop etc.) : Other details: Will need basic NIM electronic support, 3-4 3-5kV power supplies, 2-3 turbo pumps and data acquisition and control programs – possibility of collision chamber and spectrometer exists Is the project part of an international collaboration ? : Yes (Kansas State U., ATOMKI, ITS-LEIF EU network) Is the project a preparatory work for expmts. abroad? : Not necessarily but could be 1st TANDEM users meeting, Feb. 3, 2006, INP/Demokritos, Athens

12. Thank the LIBRA organizers and the DEMOKRITOS tandem staff for their help so far And in the future to come Looking forward to a mutually profitable collaboration/use of the facility Will need help setting up and running experiments all interested parties (particularly students) are invited to join tzouros@physics.uoc.gr