Apparatuses and methods are provided for applying accelerated electrons to a gaseous medium by means of an electron beam generator, which has at least one cathode for emitting electrons and at least one electron exit window, wherein a) the at least one cathode is annular and the at least one electron exit window is in the form of an annular first hollow cylinder, the annular electron exit window in the form of the first hollow cylinder forms an inner wall of an annular housing of the electron beam generator, wherein the electrons emitted by the cathode are accelerated to the ring axis of the annular housing; b) an annular second hollow cylinder is arranged within the electron exit window in the form of the first hollow cylinder and delimits an annular space between the first hollow cylinder and the second hollow cylinder; c) a cooling gas is fed through the annular space between the first hollow cylinder and the second hollow cylinder; and d) the gaseous medium to which accelerated electrons are to be applied is fed through the second hollow cylinder.

A shield device (100) is for covering a radiation window (502). The shield device (100) includes a support structure (102) with an opening (106), and a flexible foil (104) covering at least the opening (106) of the support structure (102). The foil (104) includes carbon nanotubes in a form of a network (202) and the foil (104) is configured to allow radiation to pass through the foil (104) at least partly and to prevent objects (302) to pass through the foil (104). A radiation arrangement (500) includes a shield device (100), and a method is for producing a shield device (100) for a radiation window (502).

There is provided an exit window for an electron beam from a linear accelerator for use in producing radioisotopes. The exit window comprises a cylindrical channel operatively connectable at one end to a vacuum chamber configured for travel of the electron beam; and a domed dished head at the other end of the channel, the dished head comprising a convex portion having a protruding crown configured for pass-through of the electron beam wherein the geometry of the domed dished head is proportioned to resist pressure stress created by cooling medium circulating around the protruding crown and the vacuum in the cylindrical channel and to maintain the combined cooling medium pressure stress and pulsed electron beam thermal stress below the fatigue limit of the material forming the exit window.

There is provided an exit window for an electron beam from a linear accelerator for use in producing radioisotopes. The exit window comprises a cylindrical channel operatively connectable at one end to a vacuum chamber configured for travel of the electron beam; and a domed dished head at the other end of the channel, the dished head comprising a convex portion having a protruding crown configured for pass-through of the electron beam wherein the geometry of the domed dished head is proportioned to resist pressure stress created by cooling medium circulating around the protruding crown and the vacuum in the cylindrical channel and to maintain the combined cooling medium pressure stress and pulsed electron beam thermal stress below the fatigue limit of the material forming the exit window.

Disclosed is an energy beam emission device including: an electron discharge unit having a long electron discharge part; a housing having a window from which energy beams are emitted on the basis of electrons discharged from the electron discharge part; and a unit accommodation part capable of accommodating the electron discharge unit. A plurality of positioning parts are provided between an outer surface of the electron discharge unit and an inner surface of the unit accommodation part, the positioning parts being slidably in contact with an outer surface of the electron discharge unit or an inner surface of the unit accommodation part and performing positioning of the electron discharge part with respect to the unit accommodation part.

Disclosed is an energy beam emission device including: an electron discharge unit having a long electron discharge part; a housing having a window from which energy beams are emitted on the basis of electrons discharged from the electron discharge part; and a unit accommodation part capable of accommodating the electron discharge unit. A plurality of positioning parts are provided between an outer surface of the electron discharge unit and an inner surface of the unit accommodation part, the positioning parts being slidably in contact with an outer surface of the electron discharge unit or an inner surface of the unit accommodation part and performing positioning of the electron discharge part with respect to the unit accommodation part.

An electron exit window foil for use with a high performance electron beam generator operating in a corrosive environment is provided. The electron exit window foil comprises a sandwich structure having a film of Ti, a first layer of a material having a higher thermal conductivity than Ti, and a flexible second layer of a material being able to protect said film from said corrosive environment, wherein the second layer is facing the corrosive environment.

An electron exit window foil for use with a high performance electron beam generator operating in a corrosive environment is provided. The electron exit window foil comprises a sandwich structure having a film of Ti, a first layer of a material having a higher thermal conductivity than Ti, and a flexible second layer of a material being able to protect said film from said corrosive environment, wherein the second layer is facing the corrosive environment.

One or more examples relate, generally, to an apparatus. The apparatus includes a charged particle source and a charged particle pointer. The charged particle pointer urges charged particles emitted by the charged particle source in a predetermined direction. The charged particle pointer comprises a repeller, and an isolator positioned along a path extending from the repeller in the predetermined direction.

There is provided a radiation transmissive window having high radiation transmissivity. The radiation transmissive window includes: an outer frame having an opening; a radiation transmissive film closing off the opening; and a grid member that partitions the opening into a plurality of small opening portions. The grid member has a first portion, a second portion at a smaller distance to the center of the opening than the first portion, and a third portion at a smaller distance to the center of the opening than the second portion. The first portion is greater in width than the second portion. The second portion is greater in width than the third portion.