A borehole muon detector for muon radiography or geotomography is provided, the borehole muon detector including a substantially cylindrical housing, which defines a bore, a pair of end caps, each end cap sealing an end of the cylindrical housing and a plurality of sealed drift tubes which are longitudinally disposed in the bore of the housing to form a bundle of drift tubes, wherein each sealed drift tube comprises: a centrally located anode wire disposed on a longitudinal axis; an inner surface which is coated with a cathode coating, the cathode coating divided into a first cathode pad and a second cathode pad by a Vernier pattern; and a timer in electrical communication with the anode wire for measuring a drift time. A system and a method are also provided.

A borehole muon detector for muon radiography or geotomography is provided, the borehole muon detector including a substantially cylindrical housing, which defines a bore, a pair of end caps, each end cap sealing an end of the cylindrical housing and a plurality of sealed drift tubes which are longitudinally disposed in the bore of the housing to form a bundle of drift tubes, wherein each sealed drift tube comprises: a centrally located anode wire disposed on a longitudinal axis; an inner surface which is coated with a cathode coating, the cathode coating divided into a first cathode pad and a second cathode pad by a Vernier pattern; and a timer in electrical communication with the anode wire for measuring a drift time. A system and a method are also provided.

A drift tube construction includes a thin wall aluminum tube with a thin wire at its center attached to a terminal. The tube is plugged at both ends. The terminal is embedded at the center of the plug with material insulating it from Drift tube main body. The Drift tube assembly is sealed and filled with a gas mixture. A voltage is applied to the thin wire via the terminal. Current drift tubes employ plastic material to insulate the terminal from Drift tube main body and O-rings to provide a near hermetic seal.

Various configurations of electrically conductive, gas-sealed connections between two pieces of aluminum are described along with methods of making an electrically conductive, gas-sealed connection between two pieces of aluminum.

Various configurations of electrically conductive, gas-sealed connections between two pieces of aluminum are described along with methods of making an electrically conductive, gas-sealed connection between two pieces of aluminum.

An ion filter is used for a gas detector including a gas electron multiplier. The ion filter includes: an insulating substrate; a first patterned conductive layer on one main surface of the insulating substrate; and a second patterned conductive layer on another main surface of the insulating substrate. The ion filter has a plurality of through-holes formed along a thickness direction of the insulating substrate on which the first patterned conductive layer and the second patterned conductive layer are formed. The one main surface of the insulating substrate is disposed on an upstream side in a movement direction of electrons in the gas detector. The other main surface of the insulating substrate is disposed on a downstream side in the movement direction of the electrons in the gas detector. The first patterned conductive layer has a line width thicker than a line width of the second patterned conductive layer.

Various configurations of muon drift tubes for use in muon tomography are described and involve aluminum end caps coupled to an aluminum tube, an electrode in each of the end caps, and an anode wire extending between the electrodes. A two-part electrically conductive, gas-sealed, connection is located between an aluminum end cap and the aluminum tube. Methods of making those configurations of muon drift tubes are also described.

Disclosed include a drift tube for particle detection, a detection system including one or more of the drift tubes, a method of producing a drift tube, and a detection method using a drift tube and/or a detection systems. The drift tube may include: a housing tube extending along a longitudinal axis and structured to include a first end, a second end, and an internal surface configured as a cathode, a first end cap and a second end cap hermetically engaged to and electrically isolated from the first end and the second end of the housing tube, respectively; a detection gas enclosed inside the housing tube and configured for undergo ionization by charged particles; and an anode wire traversing the housing tube along the longitudinal axis and being configured to detect the ionization that indicates a track of the charged particles inside the drift tube.

A borehole muon detector for muon radiography or geotomography is provided, the borehole muon detector including a substantially cylindrical housing, which defines a bore, a pair of end caps, each end cap sealing an end of the cylindrical housing and a plurality of sealed drift tubes which are longitudinally disposed in the bore of the housing to form a bundle of drift tubes, wherein each sealed drift tube comprises: a centrally located anode wire disposed on a longitudinal axis; an inner surface which is coated with a cathode coating, the cathode coating divided into a first cathode pad and a second cathode pad by a Vernier pattern; and a timer in electrical communication with the anode wire for measuring a drift time. A system and a method are also provided.

A drift tube construction includes a thin wall aluminum tube with a thin wire at its center attached to a terminal. The tube is plugged at both ends. The terminal is embedded at the center of the plug with material insulating it from Drift tube main body. The Drift tube assembly is sealed and filled with a gas mixture. A voltage is applied to the thin wire via the terminal. Current drift tubes employ plastic material to insulate the terminal from Drift tube main body and O-rings to provide a near hermetic seal.