Joint Research Activity JRA 4 Multi-coincidence detectors for low-energy particles Participating countries France, Germany, Israel Tasks A) Multi-pixel detectors for low-energy particles B) CCD-camera based multifragment-detector development C) Optimization of the delay line technique D) Crossed wire detector Coordinators: Joachim Ullrich, Alexander Dorn Max Planck Institut für Kernphysik, Heidelberg, Germany

Interaction of energetic ions with matter: At least a few but usually many tens of electrons and ions are freed on a fs-time scale. Many-particle imaging and detection systems become indispensable. Present day detectors in many aspects do not fulfill the required specifications. Well-adapted selection of solutions Optimize the most promising and complementary concepts on the market Develop new, more risky technologies Joint Research Activity JRA 4:

Ion cluster collisions C 60 Observation of fragmentation and capture dynamics Xe 25+ Université Lyon Serge Martin et al.

target recoil-ions electrons projectile E-field Sophisticated imaging techniques: „Reaction Microscope“ Frankfurt, Heidelberg Complete views of atomic reactions. n e ~ 40 ~~~~~~~~~~~~> ~~~~~~~~~~~~> ~~~~~~~~~~~~> ~~~~~~~~~~~~> ~~~~~~~~~~~~> ~~~~~~~~~~~~> Collisions with ions, electrons, laser and FEL pulses

E 0 = 2000 eV |q| = 0.5 a.u. E b = E c = 5 eV Electron impact double ionization (e,3e) 59 – – – – – – – – – – 16 5 – 10 0 – 5 E q q q q

Coulomb explosion imaging Max-Planck-Institut für Kernphysik Heidelberg, Weizmann Institut, Rehovot D. Zajfman et al. Direct experimental determination of the molecular structure

Three-dimensional element mapping with a subnanometer spatial resolution. Tomographic Atom Probe (TAP) Université de ROUEN B. Deconihout et al. HV pulse Field ion microscope

Ion surface collisions Institut für Kernphysik, Frankfurt Horst Schmidt-Böcking, T. Jahnke

Potentially hundreds of simultaneously hitting particles can be detected with a position resolution and sub-ns time resolution Presently there is no ideal read-out and electronic processing concept being able to fully exploit the MCP specifications. Key role: The particle detector

Task A Multi-pixel detectors A. Dorn, MPIK, Heidelberg Task B CCD-camera based detectors D. Zajfmann, WIS, Rehovot Task C Optimization of the delay line technique O. Jagutzki, ROE, Kelkheim Task D Crossed wire detector H. Rothard, CEA, CIRIL/Caen

Task A: Multi-pixel detectors Independent readout of a large number of anode-pixels + direct approach + good multi-hit capability, (parallel processing) - costly, large number of electronic processing channels 64 pixel MCP detector with parallel TDC and ADC readout CNRS-IPNO, Orsay 256 pixel semi- conductor detector CNRS-LASIM Lyon 8196 pixel detector MPIK Heidelberg Workpackage 1 Workpackage 2Workpackage 3 - up to 8192 pixels - simultaneous time and amplitude processing - semiconductor pixel detector Existing versions 256 (16x16) pixels at most NewLEIF

Excellent time resolution and signal processing rate at relaxed multi-hit capacity and low position resolution Realization: Fast charge preamp. on board Usage of ASICs (TDC) developed by CERN CNRS-IPNO, Institut de Physique Nucléaire, Orsay A detector for mass spectroscopy purposes for processes with high ion yields (many simultaneously hitting ions) S. DellaNegra R. Selem 64 pixels, each with TDC and ADC channels Specifications: 150 ps timing resolution 2 to 4% energy resolution (analysis of the pulse hight distribution allows to determine the number of ions hitting one pixel) dead time < 20 ns time range 10 to 2 ms (heavy ions) read-out rate up to 100 kHz PCI,USB2 standard

Multi-pixel semiconductor detector with moderate position and good time-resolution at potentially high data-processing rates Passivated Implanted Planar Silicon (PIPS) Detector ? Heigh threshold: tens of keV ? Large integration time: microssec. ? Low position resolution Detection of electrons accellerated to 20 keV Signal amplification and serial data transfer with ASICs Up to 256 individual elements Canberra Inc. CNRS-LASIM, University Lyon Serge Martin et al. surface barrier silicon detector Specifications: ns timing resolution Position resolution few 100 Energy resolution sufficient to identify the number of electrons impinging on one pixel 16 hits per pixel in a 100 ns time window Relaxed vacuum requirements compared to MCP

10 ns 100 MHz sampling of 25 ns wide preamp pulse MPIK –Heidelberg write read preamplifier pulse shaping analog pipeline 1 of 160 cells pixel 1 of 128 channels multiplexer 4x 32 to 1 to vacuum- feedthrough, ADC Up to 8192 pixels individually read-out in time and amplitude by ASICs with 128 channels each. Germanium layer vacuum separation ceramics induced charge A. Dorn, J. Ullrich

1 ns timing resolution < 0.2 mm position res. (0.8 mm pixel size) No dead-time for > 3 mm, 20 ns for smaller distances 5 hits per pixel -> Improved version of the Beetle chip First detector version with 80 mm diameter and 2048 pixels (16 chips) anode. Second version 8192 pixels (64 chips). (CERN LHCb: channels) Optimum multi-hit capacity at good signal processing rate and moderate time and position resolution Beetle chip, developed by MPIK and Kirchhoff institute Heidelberg for LHCb at CERN

Task C: Optimization of the delay-line technique + simple concept, low complexity and costs + high data processing rates + good time and position resolution - restricted multi-hit cabability Optimization of the delay- line concept ROE, Roentdek company One workpackage:

ROE, Roentdek company Ottmar Jagutzki et al. Good signal processing rate, good position and time resolution at relaxed multi-hit capacity. NewLEIF developements: improved delay-lines faster electronics, flash ADCs/faster multi-hit TDCs x y z

MCP stack Phosphor screen CCD-camera computer + good position resolution - timing has to be performed separately - noise - slow data readout (frame rate < 100 Hz) Timing with segmented anode timing resolution < 1ns for all events on different positions NewLEIF Purely CCD based concept WIS, Weizmann Institute Rehovot CCD readout combined with delay-line technique CNRS – GPM Université de Rouen Workpackage 1Workpackage 2 Task B: CCD-camera based multifragment-detectors

WIS –Rehovot P1 P2 P1 P2 Oded Heber, Daniel Zajfmann A purely CCD based concept P1 P2 Shutter MCP + Phosphor screen

far close Example: Letters illuminated by a single ns laser pulse Envisaged specifications: + timing resolution down to 0.2 ns + position resolution down to < 0.05 mm + no dead time for different positions - no multi hit detection for the same position - low signal processing rate < 100 1/s Optimum time-, position and multi-hit capacity at low signal processing rates

CNRS – GPM, Université de ROUEN : Optimum time-, position and multi-hit capacity at low signal processing rates + timing resolution down to 0.07 ns + position resolution down to < 0.1 mm + no dead time for different positions - low signal processing rate < 100/s Phosphor screen 2 GHz digitalisation 2 ns Delay-line CCD readout combined with the delay-line technique B. Deconihout et al.

Task D: Crossed wire detector + simple concept + moderate number of signal lines / electronic units + no dead time for different x,y positions - restricted multi-hit cabability Improved crossed wire detector CEA, CIRIL, Caen UBI, University Bielefeld One workpackage

CEA, CIRIL UBI, University Bielefeld Improved crossed wire detector Present specifications: timing resolution down to 0.2 ns position resolution 2.5 mm x y printed circuit board 16x16 „wires“ 2.5 mm NewLEIF developments: UHV compatibel anode improvement of the electronics to achieve higher count rates Cost effective readout scheme with good timing resolution, low position and moderate multi-hit resolution H. Rothard, U. Werner et al.

Management Structure

Two JRA4 meetings will be held per annum as part of a larger I3 meeting Progress reports Working visits Website as a subsection of the proposed I3 website Monitoring and reporting progress Annual progress reports are given by the task managers Monitoring of delivery of milestones Evaluation after 18 month NewLEIF newsletter Monthly updates of the JRA4 part of the NewLEIF homepage Communication