An in-vacuum light sensor system, including a light sensor assembly comprising a photocathode configured for converting an impinging photon to a photoelectron, a semiconductor diode configured for multiplying the photoelectron impinging thereon, and a housing including vacuum-compatible materials configured for being placed in a vacuum chamber. The housing is configured for housing the photocathode and the semiconductor diode and for propagation of the photoelectron from the photocathode to the semiconductor diode. An electrical biasing subassembly is configured for electrically biasing at least the photocathode and the semiconductor diode, and the vacuum chamber is configured for positioning the light sensor apparatus therein.

An ion detection system comprising an upper plate configured for propagation of ions therethrough, a lower plate comprising a converter configured for converting ions impinging thereon to secondary electrons, a secondary electron multiplication assembly configured for receiving the secondary electrons and comprising at least one or optionally a series of oppositely facing pairs of dynodes, wherein in the optional series of oppositely facing pairs of dynodes, each pair is spaced apart from an adjacent pair, and wherein a first electric field is created in between the oppositely facing pair of dynodes. A magnetic system is provided for generating a magnetic field.

In-situ methods for the batch fabrication of flat-panel micro-channel plate (MCP) photomultiplier tube (PMT) detectors (MCP-PMTs), without transporting either the window or the detector assembly inside a vacuum vessel are provided. The method allows for the synthesis of a reflection-mode photocathode on the entrance to the pores of a first MCP or the synthesis of a transmission-mode photocathode on the vacuum side of a photodetector entrance window.

In-situ methods for the batch fabrication of flat-panel micro-channel plate (MCP) photomultiplier tube (PMT) detectors (MCP-PMTs), without transporting either the window or the detector assembly inside a vacuum vessel are provided. The method allows for the synthesis of a reflection-mode photocathode on the entrance to the pores of a first MCP or the synthesis of a transmission-mode photocathode on the vacuum side of a photodetector entrance window.

An MCP assembly of this embodiment is provided with an MCP unit and a flexible sheet electrode having a structure for facilitating handling thereof as a single body. The flexible sheet electrode is constituted by a mesh area provided with plural openings and a deformation suppressing portion surrounding the mesh area. Both the mesh area and the deformation suppressing portion are comprised of the same conductive material, and physical strength of the deformation suppressing portion is higher than that of the mesh area. With this configuration, the physical strength of an entire flexible sheet electrode is secured even if an opening ratio of the mesh area is increased, so that the handling of the flexible sheet electrode as a single body is facilitated.

A gas electron multiplier (GEM), used to track cosmic ray muons, can have readout electrodes oriented in a helical pattern so that it can fit inside a narrow aperture borehole. The helical orientation of the readout electrodes provides for high spatial resolution and yet is cost effective to manufacture. The GEM can have an insulation layer, a plurality of conduction layers and an inner layer comprising a plurality of helical conductive stripes extending between two ends of the GEM.

A gas electron multiplier (GEM), used to track cosmic ray muons, can have readout electrodes oriented in a helical pattern so that it can fit inside a narrow aperture borehole. The helical orientation of the readout electrodes provides for high spatial resolution and yet is cost effective to manufacture. The GEM can have an insulation layer, a plurality of conduction layers and an inner layer comprising a plurality of helical conductive stripes extending between two ends of the GEM.

The MCP assembly of this embodiment is formed at least of a conductive upper support member, an MCP unit, an output electrode, a flexible sheet electrode, and a conductive lower support member as a structure for improving handleability of a flexible sheet electrode having a mesh area. The flexible sheet electrode includes the mesh area provided with plural openings. The flexible sheet electrode and the lower support member are physically and electrically connected to each other, and the flexible sheet electrode is sandwiched between the upper support member and the lower support member. As a result, even if the flexible sheet electrode becomes thin as an opening ratio of the mesh area increases, potential is set while the flexible sheet electrode is firmly held in the MCP assembly.

An MCP assembly of this embodiment is provided with an MCP unit and a flexible sheet electrode having a structure for facilitating handling thereof as a single body. The flexible sheet electrode is constituted by a mesh area provided with plural openings and a deformation suppressing portion surrounding the mesh area. Both the mesh area and the deformation suppressing portion are comprised of the same conductive material, and physical strength of the deformation suppressing portion is higher than that of the mesh area. With this configuration, the physical strength of an entire flexible sheet electrode is secured even if an opening ratio of the mesh area is increased, so that the handling of the flexible sheet electrode as a single body is facilitated.

The MCP assembly of this embodiment is formed at least of a conductive upper support member, an MCP unit, an output electrode, a flexible sheet electrode, and a conductive lower support member as a structure for improving handleability of a flexible sheet electrode having a mesh area. The flexible sheet electrode includes the mesh area provided with plural openings. The flexible sheet electrode and the lower support member are physically and electrically connected to each other, and the flexible sheet electrode is sandwiched between the upper support member and the lower support member. As a result, even if the flexible sheet electrode becomes thin as an opening ratio of the mesh area increases, potential is set while the flexible sheet electrode is firmly held in the MCP assembly.