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Since third-generation synchrotron radiation facilities are highly brilliant sources, the scattering of a partially coherent beam gives rise to strong interference effects. We present and discuss in this contribution the comparison of simulated and experimental diffraction patterns collected with an optical device made by two identical flat Micro Channel Plates (MCPs) illuminated by synchrotron radiation at different energies. The experimental patterns clearly show the increase of the density of the main peak with respect to those collected with a single flat MCP. Data demonstrate that the use of a device based on two MCPs is an ideal optical system to condense the primary radiation in a narrow intense central peak. [ABSTRACT FROM AUTHOR]

We describe a pin-less design for the high voltage (HV) resistive divider of the all-glass LAPPD TM 8 in.-square thin photodetector module. The divider, which distributes high voltage applied to the photocathode to the two micro-channel plates (MCPs) that constitute the amplification stage, is comprised of the two MCPs and three glass mechanical spacers, each of which is coated with a resistive layer using atomic layer deposition (ALD). The three glass grid spacers and the two MCPs form a continuous resistive path between cathode and anode, with the voltages across the MCPs and the spacers determined by the resistance of each. High voltage is applied on an external tab on the top glass window that connects to the photocathode through the metal seal. The DC ground is supplied by microstrips on the bottom glass plate that form the high-bandwidth anode. The microstrips exit the package through the glass-frit seal of the anode base-plate and the package sidewall. The divider is thus completely internal, with no HV pins penetrating the low-profile flat glass package. Measurements of the performance of the divider are presented for the 8 in.-square MCP and spacer package in a custom test fixture and for an assembled externally pumped LAPPD TM prototype with an aluminum photocathode. [ABSTRACT FROM AUTHOR]

Abstract: Accuracy of nuclear mass measurements in storage rings depends critically on the accuracy with which the revolution times of stored ions can be obtained. In such experiments, micro-channel plates (MCP) are used as timing detectors. Due to large phase space of injected secondary beams, a large number of ions cannot be stored in the ring and is lost within the first few revolutions. However, these ions interact with the detector and can saturate the MCP and thus deteriorate its performance. In order to eliminate such effects, a fast, pulsed high-voltage power supply (PHVPS) has been employed which keeps the detector switched-off during the first few revolutions. The new detector setup was taken into operation at the Experimental Cooler-Storage-Ring CSRe in Lanzhou and resulted in a significant improvement of the detector amplitude and efficiency characteristics. [Copyright &y& Elsevier]

Micro-Channel Plate devices (MCP) provide fast signals with rise-times in the 100 ps regime. The coupling of the MCP anode plane to 50 Ω transmission lines allows both a precise time measurement and additionally the potential for a position measurement with an accuracy of a few hundred microns for large-area devices. We present position measurement results obtained with MCPs from Photonis, 10-cm long transmission lines, and a calibrated laser source, using waveform processing after digitization. A detailed simulation of the transmission lines is also presented, including simulation results for transmission lines up to 1-m in length.We compare the measured position resolution for two identical setups but with MCPs of different pore diameters: 25 and 10 microns. [ABSTRACT FROM AUTHOR]

The measurement of time-of-flight (TOF) of relativistic particles in high-energy colliders with picosecond resolution would qualitatively change the ability to identify underlying parton-level processes at future colliders or upgrades of existing detectors. We have measured the timing properties of three micro-channel plate photo-multiplier tubes (MCPPMTs) from Photonis; one with 1024 anodes and the other two with 64 anodes. The 1024-anode 10-micron pore tube uses a charge-collection scheme at the anode to provide equal arrival time of the signal independent of the hit position of incident light on the face of the tube. The two 64-anode 25-micron pore tubes have a commercially available collection scheme and were used to find a limit on the timing resolution. We have performed these measurements using a newly assembled test-stand based on a Hamamatsu PLP-10 picosecond laser and a commercial CAMAC readout electronics system. We present these results and compare timing properties to earlier versions of the charge collection scheme. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the entrance detector of the magnetic spectrometer PRISMA recently installed at Legnaro. The detector is based on rectangular () Micro-Channel Plates (MCP). It provides a fast time signal and its position-sensitive anode allows to extract the and information. It exploits an electrostatic field for the acceleration of secondary electrons from a thin Carbon foil () onto the MCP assembly. The electrons are guided by a parallel magnetic field. Good performances were obtained in the laboratory tests. The detector is presently installed at the entrance of PRISMA and gives resolutions in time, and 1mm in both and -axes, with efficiency , in typical experiments with heavy-ion beams. [Copyright &y& Elsevier]

This article reviews the principles, performance and limitations of position-sensitive vacuum photon detectors which find applications in high-energy physics experiments. Particular emphasis is devoted to multi-anode photo-multiplier tubes, devices based on micro-channel plates and hybrid photon detectors. Over the past 25 years, innovation in industrial environments, research centres and universities has led to the invention and consequent optimization of a number of position-sensitive photon detectors. Miniaturization of known principles and components or the smart combination of established concepts allowed to build new classes of finely-segmented photodetectors which in turn enabled new applications in high-energy physics, but also elsewhere. The imaging of Cherenkov light in hostile hadron environments like at the CERN Large Hadron Collider is perhaps one of the most demanding applications which would not have been possible without this breakthrough. [ABSTRACT FROM AUTHOR]

The micro-channel plate based particle tracking detector described here is part of the detector system used in a series of measurements of astrophysical (α , p) reactions, which will be studied at the Radioactive Ion Beam Line in Lanzhou, China. This detector will provide on a particle-by-particle basis tracking information and arrival time of radioactive beams with intensities up to 1 0 5 particles per second. The key requirements of the experiments to the detector are that the spatial resolution is below 1 mm, the time resolution is better than 1 ns and the energy loss is less than for a parallel plate avalanche counter. The current prototype is composed of two micro-channel plate detectors with a compact electrostatic field construction and a delay-line readout. Based on the results of α -particle tests, one micro-channel detector can achieve a position resolution of 552 μ m full width at half maximum on the x axis and 735 μ m on the y axis. The tracking system can achieve 705 ps time resolution and can cope with a beam intensity of up to 5 × 1 0 6 particles per second. [ABSTRACT FROM AUTHOR]