1. Key experiment planned at HITRAP Precision spectroscopy of singly and doubly-excited states of slow HCI Max- Planck-Institut für Kernphysik, Heidelberg

2. Precision Spectroscopy: example 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 Electron Capture

3. Precision Spectroscopy: example capture into n=4 excellent resolution: 0.7eV FWHM excellent precision: 3-100 meV many states resolved simultaneously no selection rules

4. Studies with HCI from HITRAP 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

5. HITRAP Reaction- Microscope Target Jet Ion Beam Electron Detector But: - capture cross sections: 10 -14 cm 2 - target density: 10 11 cm -2 - efficiency : 10 -1 (ion & up to 2 e - ) 10 -3 (ion, 2 e - & photon) Highly resolved detection of: - few ions (100 % of 4  ) - up to 10 e - (50 % of 4  ) - photons (10 % of 4  ) Requirements from HITRAP: ion beam diameter: 0.5-1 mm at least 10 4 ions/s: single e - capture 10 5 -10 6 ions/s: multi-electron and rearrangement processes of HCI (Auger, X-rays) Photon Detectors Ion Detector Projectile analyzer

6. 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

7. The HITRAP Reaction Microscope large area ion detector (MCP) 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 present solution: kicker future solution: