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There are three coordinate systems often referred to inside the GlueX Tagger Hall. These coordinate systems have origins associated with the Goniometer center (room coordinates), Tagger Magnet center (map coordinates), and the focal plane (FP coordinates). The room coordinate system has the positive z-coordinate along the beam axis with the positive y direction pointing to the ceiling of the tagger hall from the coordinates origin placed at the Goniometer's center, where the beamline radiator is located. Figure 1 shown below, taken from a presentation by Dan Sober, shows the three coordinate systems relative to one another. The map coordinate system (magnetic mapping) places the y-coordinate along the long axis of the magnet with the positive x-axis parallel to the tagger hall floor in the direction of the focal plane. the positive z-axis of the map coordinate system points toward the tagger hall ceiling. When viewed from above the map y-coordinate is offset from the room coordinate z-axis by 6.5 degrees towards the focal plane (clockwise). The focal plane coordinate system places its x-axis along the electron focal plane with zero being at an electron energy equivalent to a photon energy around 11.7 GeV. The positive x-axis points toward increasing electron energy (decreasing photon energy). The positive y-axis of the focal plane coordinate system points towards the tagger magnet and is parallel to the tagger hall floor. This leaves the focal plane positive z-axis pointing towards the tagger hall ceiling.

There are three coordinate systems often referred to inside the GlueX Tagger Hall. These coordinate systems have origins associated with the Goniometer center (room coordinates), Tagger Magnet center (map coordinates), and the focal plane (FP coordinates). The room coordinate system has the positive z-coordinate along the beam axis with the positive y direction pointing to the ceiling of the tagger hall from the coordinates origin placed at the Goniometer's center, where the beamline radiator is located. Figure 1 shown below, taken from a presentation by Dan Sober, shows the three coordinate systems relative to one another. The map coordinate system (magnetic mapping) places the y-coordinate along the long axis of the magnet with the positive x-axis parallel to the tagger hall floor in the direction of the focal plane. the positive z-axis of the map coordinate system points toward the tagger hall ceiling. When viewed from above the map y-coordinate is offset from the room coordinate z-axis by 6.5 degrees towards the focal plane (clockwise). The focal plane coordinate system places its x-axis along the electron focal plane with zero being at an electron energy equivalent to a photon energy around 11.7 GeV. The positive x-axis points toward increasing electron energy (decreasing photon energy). The positive y-axis of the focal plane coordinate system points towards the tagger magnet and is parallel to the tagger hall floor. This leaves the focal plane positive z-axis pointing towards the tagger hall ceiling.

      

      

[[Image:Tagger_Hall_Coord.png|center|thumb|800px|Figure 1: The three coordinate systems often referred to in association with the Tagger Hall. (Image taken from a [https://halldweb.jlab.org/wiki/images/e/e0/TaggerHodoscopeEnergy-1-2017.pdf Dan Sober Presentation])]]

[[Image:Tagger_Hall_Coord.png|center|thumb|800px|Figure 8: The three coordinate systems often referred to in association with the Tagger Hall. (Image taken from a [https://halldweb.jlab.org/wiki/images/e/e0/TaggerHodoscopeEnergy-1-2017.pdf Dan Sober Presentation])]]

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[[Image:TAGM_New_Coord.png|center|thumb|500px|Figure 2: Results of a Spring 2017 survey. (Image taken from a [https://halldweb.jlab.org/wiki/images/e/e0/TaggerHodoscopeEnergy-1-2017.pdf Dan Sober Presentation])]]

[[Image:TAGM_New_Coord.png|center|thumb|500px|Figure 9: Results of a Spring 2017 survey. (Image taken from a [https://halldweb.jlab.org/wiki/images/e/e0/TaggerHodoscopeEnergy-1-2017.pdf Dan Sober Presentation])]]

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The Tagger Microscope (TAGM) contains 17 optical fiber bundle, each consists of a 5x6 array of 30 fibers for a total of 510 fibers (5 rows, 102 columns). Figure 2 below shows the fiber array as viewed by the electrons passing through the tagger magnet focal plane. Each optical fiber consists of a 2 mm² x 2 cm BCF-20 scintillating fiber (SciFi) thermally fused to 2 mm² x 165 cm BCF-98 light guide, see Figures 3 & 4. The SciFi end of each fiber is thermally bent into an "S" shape to remove the fiber from the electrons' path soon after passing through the SciFi, see Figure 5. The fiber begins its bend out of the electrons' path after only 4.5 cm. This length provides enough material past the fused joint to minimize strain on the joint resulting from the bend and fiber mounting straps, while also reducing the material in the line-of-fire that could result in backscatter.

The Tagger Microscope (TAGM) contains 17 optical fiber bundle, each consists of a 5x6 array of 30 fibers for a total of 510 fibers (5 rows, 102 columns). Figure 2 below shows the fiber array as viewed by the electrons passing through the tagger magnet focal plane. Each optical fiber consists of a 2 mm² x 2 cm BCF-20 scintillating fiber (SciFi) thermally fused to 2 mm² x 165 cm BCF-98 light guide, see Figures 3 & 4. The SciFi end of each fiber is thermally bent into an "S" shape to remove the fiber from the electrons' path soon after passing through the SciFi, see Figure 5. The fiber begins its bend out of the electrons' path after only 4.5 cm. This length provides enough material past the fused joint to minimize strain on the joint resulting from the bend and fiber mounting straps, while also reducing the material in the line-of-fire that could result in backscatter.

   

   

[[Image:Fiber_Array.png|center|thumb|1200px|Figure 2: Electron view of the TAGM scintillating fiber array.]]

[[Image:Fiber_Array.png|center|thumb|1200px|Figure 9: Electron view of the TAGM scintillating fiber array.]]

<gallery caption="Transmission of scintillation light" widths="300px" heights="300px" class="center">

<gallery caption="Transmission of scintillation light" widths="300px" heights="300px" class="center">

   Fiber_lg.jpg|Figure 3: An end view of a 2 mm² light guide fiber (BCF-98). A highly polished end such as the one shown here is required on the light guide end that interfaces with the SiPM for maximum light transmission.

   Fiber_lg.jpg|Figure 10: An end view of a 2 mm² light guide fiber (BCF-98). A highly polished end such as the one shown here is required on the light guide end that interfaces with the SiPM for maximum light transmission.

   Fiber.png|Figure 4: Image of the mating joint of 2 cm. of scintillating fiber BCF-20 (left) joined to 165 cm. light guide fiber BCF-98 (right). This picture was taken during the prototyping phase when optical epoxy was used to mate the fibers, the current method of joining fibers uses thermal fusing.

   Fiber.png|Figure 11: Image of the mating joint of 2 cm. of scintillating fiber BCF-20 (left) joined to 165 cm. light guide fiber BCF-98 (right). This picture was taken during the prototyping phase when optical epoxy was used to mate the fibers, the current method of joining fibers uses thermal fusing.

</gallery>

</gallery>

[[Image:SciFi-on-Popsicle-Stick.png|center|thumb|400px|Figure 5: CAD image of a bundle support (blue) with a mounted 5x6 fiber bundle. The 'S' bend minimizes the amount of fiber in the path of the electrons.]]

[[Image:SciFi-on-Popsicle-Stick.png|center|thumb|400px|Figure 12: CAD image of a bundle support (blue) with a mounted 5x6 fiber bundle. The 'S' bend minimizes the amount of fiber in the path of the electrons.]]

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[[Image:Magnetic_Field_Map.pdf|center|thumb|300px|Figure 3: Table of the electrons' positions as they pass through the Focal Plane.]]

[[Image:Magnetic_Field_Map.pdf|center|thumb|300px|Figure 13: Table of the electrons' positions as they pass through the Focal Plane.]]