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TDC and Coincidence Electronics • Fast Position Sensitive Detectors • Custom Designs

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Position Sensitive Detectors
Characteristics:
  • Time- and position-resolved detection of electrons and ions
  • Timing and position pulse risetimes <1ns, pulse widths <2ns
  • 10 ns multihit dead time
  • Position sensitive readout area and pattern available in custom shapes and sizes
  • Spatial resolution typically 0.5mm, depending on the custom design
  • Very compact and robust design (98mm diameter for a 40mm active detection area)

Applications:

Our fast time- and position-sensitive detectors are based on a Z-stack of three Multichannelplates (MCPs). The charge cloud, which is produced when a particle hits the MCPs, is detected on an array of anode segments. The signals from all lines are amplified and discriminated in order to be used as the particle hit position information. We are able to provide a large variety of shapes and sizes of the position sensitive area. As a standard setup we offer a detector with a 40mm diameter active area as shown in fig.1.
imaging detector
Fig. 1: Standard setup with 40mm active area
The detection area is covered by a grid like structure of 64 independent position readout lines resulting in a total number of more than 800 image pixels. The typical distance between two neighbouring lines is 1mm. By using interpolation techniques this setup provides a position resolution of 0.5mm. Other layouts can be produced with a higher spatial resolution. The diameter of the detector is 92mm, the total diameter including assembling rods to mount the detector on a flange is 98mm. Thus, the 40mm active area detector fits through DN 100 CF and ISO NW 100 vacuum flanges.
detector dimensions
Fig. 2: Some dimensions of the 40mm standard setup
position animation
Fig. 3: Example of an anode image. Klick here to view an enlarged version. The picture shows anode hit positions of N2+ molecular ions (center peak) and N+ fragment ions (outer peaks) after the N1s->sigma* excitation of nitrogene.
Your personal position readout pattern

The possibility of ordering a detector with a custom position readout pattern gives you the chance to get the optimum position readout for your experiment. You can think about parallel line patterns for rectangular slit shaped detector exits or concentric rings for ring shaped detector exits. Or you can easily save money by reducing the number of position readout lines to the amount sufficient for your particular application.

In any case if you purchased a detector with a certain pattern once, you don't have to buy a complete new setup if you just want to change the pattern's shape. In most cases we can easily design a new pattern shape to be combined with your actual setup. There are some restrictions for the exchangability of position readout patterns which result from the particular experimental setup. Just contact us for more information.