https://wiki.jlab.org/ciswiki/api.php?action=feedcontributions&user=Chgarcia&feedformat=atomCiswikidb - User contributions [en]2024-03-28T08:55:59ZUser contributionsMediaWiki 1.35.7https://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30811Mar 27 20242024-03-26T21:10:16Z<p>Chgarcia: </p>
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<div>==Updates==<br />
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* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection checks in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
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* S&A checks of the R30-3 gun in LERF Lab 3A clean room took place on Tuesday March 26 2024. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024]]<br />
** The R30-3 gun vacuum chamber was mounted by Neil Wilson and Bern Johnson on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As <u>'''''preliminary testing'''''</u>, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop.<br />
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[[File:R30-3 gun in LERF Lab 3A cleanroom 01.jpg|left|middle|thumb]]<br />
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[[File:S&A established laser launch along chamber z-axis 02.jpg|left|middle|thumb]]<br />
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[[File:Preliminary retro-reflection with mirror puck electrode still mounted to HVC.jpg|left|middle|thumb]]<br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30810Mar 27 20242024-03-26T21:08:32Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection checks in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
<br />
* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As <u>'''''preliminary testing'''''</u>, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop.<br />
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[[File:R30-3 gun in LERF Lab 3A cleanroom 01.jpg|left|middle|thumb]]<br />
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[[File:S&A established laser launch along chamber z-axis 02.jpg|left|middle|thumb]]<br />
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[[File:Back end with laser beam through HVC.jpg|left|middle|thumb]]<br />
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[[File:Preliminary retro-reflection with mirror puck electrode still mounted to HVC.jpg|left|middle|thumb]]<br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30809Mar 27 20242024-03-26T21:07:55Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
<br />
* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As <u>'''''preliminary testing'''''</u>, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop.<br />
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[[File:R30-3 gun in LERF Lab 3A cleanroom 01.jpg|left|middle|thumb]]<br />
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[[File:S&A established laser launch along chamber z-axis 02.jpg|left|middle|thumb]]<br />
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[[File:Back end with laser beam through HVC.jpg|left|middle|thumb]]<br />
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[[File:Preliminary retro-reflection with mirror puck electrode still mounted to HVC.jpg|left|middle|thumb]]<br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30808Mar 27 20242024-03-26T21:07:19Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
<br />
* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As <u>'''''preliminary testing'''''</u>, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop.<br />
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[[File:R30-3 gun in LERF Lab 3A cleanroom 01.jpg|left|middle|thumb]]<br />
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[[File:S&A established laser launch along chamber z-axis 02.jpg|left|middle|thumb]]<br />
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[[File:Preliminary retro-reflection with mirror puck electrode still mounted to HVC.jpg|left|middle|thumb]]<br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30807Mar 27 20242024-03-26T21:06:49Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
<br />
* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As <u>'''''preliminary testing'''''</u>, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop.<br />
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[[File:R30-3 gun in LERF Lab 3A cleanroom 01.jpg|left|middle|thumb]]<br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]<br />
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[[File:S&A established laser launch along chamber z-axis 02.jpg|left|middle|thumb]]<br />
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[[File:Back end with laser beam through HVC.jpg|left|middle|thumb]]<br />
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[[File:Preliminary retro-reflection with mirror puck electrode still mounted to HVC.jpg|left|middle|thumb]]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30806Mar 27 20242024-03-26T21:06:21Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
<br />
* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As preliminary testing, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop.<br />
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[[File:R30-3 gun in LERF Lab 3A cleanroom 01.jpg|left|middle|thumb]]<br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]<br />
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[[File:S&A established laser launch along chamber z-axis 02.jpg|left|middle|thumb]]<br />
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[[File:Preliminary retro-reflection with mirror puck electrode still mounted to HVC.jpg|left|middle|thumb]]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:Preliminary_retro-reflection_with_mirror_puck_electrode_still_mounted_to_HVC.jpg&diff=30805File:Preliminary retro-reflection with mirror puck electrode still mounted to HVC.jpg2024-03-26T21:06:18Z<p>Chgarcia: </p>
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<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:Back_end_with_laser_beam_through_HVC.jpg&diff=30804File:Back end with laser beam through HVC.jpg2024-03-26T21:05:24Z<p>Chgarcia: </p>
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<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:S%26A_established_laser_launch_along_chamber_z-axis_02.jpg&diff=30803File:S&A established laser launch along chamber z-axis 02.jpg2024-03-26T21:04:33Z<p>Chgarcia: </p>
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<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:R30-3_gun_in_LERF_Lab_3A_cleanroom_01.jpg&diff=30802File:R30-3 gun in LERF Lab 3A cleanroom 01.jpg2024-03-26T21:03:29Z<p>Chgarcia: </p>
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<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30801Mar 27 20242024-03-26T21:01:55Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
<br />
* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As preliminary testing, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop. <br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30800Mar 27 20242024-03-26T21:01:39Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
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* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024|here]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As preliminary testing, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop. <br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30799Mar 27 20242024-03-26T21:01:12Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
<br />
* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As preliminary testing, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop. <br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30798Mar 27 20242024-03-26T21:00:07Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
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* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details [[https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024|here]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As preliminary testing, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop. <br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30797Mar 27 20242024-03-26T20:58:58Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
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* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
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* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details[[https://wiki.jlab.org/ciswiki/index.php/Mar 20_2024|March 20 2024 meeting minutes]]<br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As preliminary testing, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop. <br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30796Mar 27 20242024-03-26T20:57:59Z<p>Chgarcia: </p>
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<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
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* S&A checks of the R30-3 gun in LERF Lab 3A clean room. See details here: <br />
** The R30-3 gun vacuum chamber was mounted on a sturdy 80/20 frame table with optical breadboard top. <br />
** S&A surveyed the gun chamber to find the chamber z axis.<br />
** Then S&A established a laser launch coincidental with the gun chamber z-axis<br />
** As preliminary testing, we inserted a mirror puck. The retro-reflection indicates the plane of the mirror puck is ~ 0.8 degree w.r.t. the chamber axis. <br />
** We will do more retro-reflection testing with a molybdenum puck and GaAs wafer once the Teflon puck manipulator arrives from the shop. <br />
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=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30795Mar 27 20242024-03-26T20:52:05Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** [[File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf|right|middle|thumb]]<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:JL0163328,_PUCK_MANIPULATOR_END_ADAPTER_TEFLON_24_in_long.pdf&diff=30794File:JL0163328, PUCK MANIPULATOR END ADAPTER TEFLON 24 in long.pdf2024-03-26T20:52:02Z<p>Chgarcia: </p>
<hr />
<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_27_2024&diff=30793Mar 27 20242024-03-26T20:51:35Z<p>Chgarcia: Created page with "==Updates== * Fabrication ** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator wil..."</p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** A new puck manipulator made out of Teflon and 24 inches long was designed and drawing submitted to the shop for fabrication. This manipulator will be used to insert pucks into the spherical electrode while still mounted to the gun vacuum chamber during S&A and laser retro-reflection chess in the LERF Lab 3A clean room.<br />
** <br />
<br />
<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=200_kV_Polarized_Gun&diff=30792200 kV Polarized Gun2024-03-26T20:48:30Z<p>Chgarcia: /* R30-4 200 kV Gun SAD 2024 Planning Meetings */</p>
<hr />
<div>* The 200 kV gun (R30-3 with spherical electrode and 18" gun HVC) was installed in CEBAF during SAD 2023.<br />
<br />
* This gun performed as designed in terms of vacuum, and high voltage: no field emission at 200 kV after conditioning with Kr to ~240 kV.<br />
* It has two problems:<br />
** The beam waist is ~ 6 cm downstream of the GaAs wafer, compared to ~ 40 cm from the Tee electrode 14" HVC R28-2 gun operated in CEBAF for years at 130 kV.<br />
** It was a not possible to obtain the laser retro-reflection.<br />
* The gun was then removed from the injector and replaced with the R28-2 gun.<br />
* The SAD 2024 links below capture the planning for fixing these problems in the R30-3 gun (which will be version R30-4) and for installing it in May 2024.<br />
<br />
<br />
==R30-4 200 kV Gun SharePoint site==<br />
[https://jeffersonlab.sharepoint.com/:f:/s/CIS/Ejp9S0WdeXtPgFm_bwwkuEAB0gEzYKg7Ci0UfKK8qQnPfQ?e=1tfGAH R30-4 200 kV SharePoint site]<br />
<br />
<br />
Contains:<br />
* Pierce cathode end piece geometry and beam parameter space table<br />
* Notes, studies, and documentation<br />
* Electrostatics and beam dynamics modeling and simulation results<br />
<br />
==R30-4 200 kV Gun SAD 2024 Planning Meetings==<br />
<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_05_2024 Jan 05, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_10_2024 Jan 10,2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_17_2024 Jan 17, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_24_2024 Jan 24, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_30_2024 Jan 31, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_7_2024 Feb 7, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_14_2024 Feb 14, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_21_2024 Feb 21, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Feb_28_2024 Feb 28, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_6_2024 Mar 6, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_13_2024 Mar 13, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024 Mar 20, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_27_2024 Mar 27, 2024]<br />
<br />
==R30-3 200 kV Gun SAD 2023 Installation Links==<br />
<br />
* ATLIS => https://tasklists.jlab.org/atlis/tasks/108541<br />
* Marcy's Gantt chart goes here => https://jeffersonlab-my.sharepoint.com/:x:/g/personal/marcy_jlab_org/EUe-xbLpNR1IsV28fyi20FUBC4bUllOnMnAYlXemA7C82Q<br />
* List of photocathodes at end of Phase 1 (5/10/2021) - https://logbooks.jlab.org/entry/3876517<br />
<br />
==R30-3 200 kV Gun SAD 2023 Planning Meetings==<br />
<br />
* Feb 20, 2023 => * Carlos SAD schedule [[Media:Gun swap planning 1 week before and 1 week after SAD start.pptx]]<br />
* Feb 02, 2022 => [[Feb 2, 2022 - Group meeting]] - Group meeting + 200 kV gun<br />
* Jan 26, 2022 => [[200 kV Gun - Jan 26, 2022]]<br />
<br />
==Links==<br />
<br />
* [https://wiki.jlab.org/ciswiki/index.php/18%22_Photogun_ala_GTS Carlos 18" Gun Page]<br />
* Gun Anode - Carlos's update https://wiki.jlab.org/ciswiki/index.php/Anode</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_20_2024&diff=30791Mar 20 20242024-03-26T20:33:53Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** Received two more cathode front end 16/30 samples from machine shop. These samples will be polished using sandpaper to remove machining marks from cone prior to barrel polishing.<br />
* The following plans was developed with Survey and alignment<br />
**Objective 1: Establish gun chamber Z axis using the anode as US aperture and flange as DS aperture<br />
**Objective 2: Establish spherical electrode Z axis while on a fixture outside the gun chamber<br />
**Objective 3: Compare the two and guide electrode installation assembly to make the two Z axes as coincident as possible, or determine difference between the two to help with gun alignment in tunnel<br />
**Objective 4: Determine difference between laser retro-reflection (with GaAs and with mirror pucks) and electrode Z-axis <br />
<br />
Tasks and approximate timeline: <br />
<br />
* Week of March 18:<br />
** Carlos coordinates with Neil Wilson to move the breadboard top to 80/20 tall table along with the gun vacuum chamber, and position the gun to back (or front?) end of table with anode facing the SS table in the back of the clean room<br />
** Carlos coordinates with Marcy availability of one mirror puck, and one puck with GaAs wafer<br />
** Carlos finds a sufficiently long rod to manipulate pucks inside the gun chamber<br />
* Week of March 25:<br />
** S&A executes a dry run of all objectives, but keep in mind the dry run starts with the electrode mounted to the vacuum chamber<br />
* Week of April 15:<br />
** S&A executes objectives 1-4 with the rebuilt electrode assembly. The rebuilt electrode will have a new front end piece with shallower cone angle.<br />
* Week of May 27:<br />
** S&A assists in the tunnel with gun alignment<br />
* Week of June 17:<br />
** S&A assist in the tunnel with laser retro-reflection<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_20_2024&diff=30790Mar 20 20242024-03-26T20:33:33Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** Received two more cathode front end 16/30 samples from machine shop. These samples will be polished using sandpaper to remove machining marks from cone prior to barrel polishing.<br />
* The following plans was developed with Survey and alignment <br />
Objective 1: Establish gun chamber Z axis using the anode as US aperture and flange as DS aperture<br />
Objective 2: Establish spherical electrode Z axis while on a fixture outside the gun chamber<br />
Objective 3: Compare the two and guide electrode installation assembly to make the two Z axes as coincident as possible, or determine difference between the two to help with gun alignment in tunnel<br />
Objective 4: Determine difference between laser retro-reflection (with GaAs and with mirror pucks) and electrode Z-axis <br />
<br />
Tasks and approximate timeline: <br />
<br />
* Week of March 18:<br />
** Carlos coordinates with Neil Wilson to move the breadboard top to 80/20 tall table along with the gun vacuum chamber, and position the gun to back (or front?) end of table with anode facing the SS table in the back of the clean room<br />
** Carlos coordinates with Marcy availability of one mirror puck, and one puck with GaAs wafer<br />
** Carlos finds a sufficiently long rod to manipulate pucks inside the gun chamber<br />
* Week of March 25:<br />
** S&A executes a dry run of all objectives, but keep in mind the dry run starts with the electrode mounted to the vacuum chamber<br />
* Week of April 15:<br />
** S&A executes objectives 1-4 with the rebuilt electrode assembly. The rebuilt electrode will have a new front end piece with shallower cone angle.<br />
* Week of May 27:<br />
** S&A assists in the tunnel with gun alignment<br />
* Week of June 17:<br />
** S&A assist in the tunnel with laser retro-reflection<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_20_2024&diff=30789Mar 20 20242024-03-26T20:32:59Z<p>Chgarcia: Created page with "==Updates== * Fabrication ** Received two more cathode front end 16/30 samples from machine shop. These samples will be polished using sandpaper to remove machining marks fro..."</p>
<hr />
<div>==Updates==<br />
<br />
* Fabrication<br />
** Received two more cathode front end 16/30 samples from machine shop. These samples will be polished using sandpaper to remove machining marks from cone prior to barrel polishing.<br />
* The following plans was developed with Survey and alignment <br />
<br />
Objective 1: Establish gun chamber Z axis using the anode as US aperture and flange as DS aperture<br />
Objective 2: Establish spherical electrode Z axis while on a fixture outside the gun chamber<br />
Objective 3: Compare the two and guide electrode installation assembly to make the two Z axes as coincident as possible, or determine difference between the two to help with gun alignment in tunnel<br />
Objective 4: Determine difference between laser retro-reflection (with GaAs and with mirror pucks) and electrode Z-axis<br />
<br />
Tasks and approximate timeline:<br />
<br />
*Week of March 18:<br />
**Carlos coordinates with Neil Wilson to move the breadboard top to 80/20 tall table along with the gun vacuum chamber, and position the gun to back (or front?) end of table with anode facing the SS table in the back of the clean room<br />
**Carlos coordinates with Marcy availability of one mirror puck, and one puck with GaAs wafer<br />
**Carlos finds a sufficiently long rod to manipulate pucks inside the gun chamber<br />
*Week of March 25:<br />
**S&A executes a dry run of all objectives, but keep in mind the dry run starts with the electrode mounted to the vacuum chamber<br />
*Week of April 15:<br />
**S&A executes objectives 1-4 with the rebuilt electrode assembly. The rebuilt electrode will have a new front end piece with shallower cone angle.<br />
*Week of May 27:<br />
**S&A assists in the tunnel with gun alignment<br />
*Week of June 17:<br />
**S&A assist in the tunnel with laser retro-reflection<br />
<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=200_kV_Polarized_Gun&diff=30788200 kV Polarized Gun2024-03-26T20:28:09Z<p>Chgarcia: /* R30-4 200 kV Gun SAD 2024 Planning Meetings */</p>
<hr />
<div>* The 200 kV gun (R30-3 with spherical electrode and 18" gun HVC) was installed in CEBAF during SAD 2023.<br />
<br />
* This gun performed as designed in terms of vacuum, and high voltage: no field emission at 200 kV after conditioning with Kr to ~240 kV.<br />
* It has two problems:<br />
** The beam waist is ~ 6 cm downstream of the GaAs wafer, compared to ~ 40 cm from the Tee electrode 14" HVC R28-2 gun operated in CEBAF for years at 130 kV.<br />
** It was a not possible to obtain the laser retro-reflection.<br />
* The gun was then removed from the injector and replaced with the R28-2 gun.<br />
* The SAD 2024 links below capture the planning for fixing these problems in the R30-3 gun (which will be version R30-4) and for installing it in May 2024.<br />
<br />
<br />
==R30-4 200 kV Gun SharePoint site==<br />
[https://jeffersonlab.sharepoint.com/:f:/s/CIS/Ejp9S0WdeXtPgFm_bwwkuEAB0gEzYKg7Ci0UfKK8qQnPfQ?e=1tfGAH R30-4 200 kV SharePoint site]<br />
<br />
<br />
Contains:<br />
* Pierce cathode end piece geometry and beam parameter space table<br />
* Notes, studies, and documentation<br />
* Electrostatics and beam dynamics modeling and simulation results<br />
<br />
==R30-4 200 kV Gun SAD 2024 Planning Meetings==<br />
<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_05_2024 Jan 05, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_10_2024 Jan 10,2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_17_2024 Jan 17, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_24_2024 Jan 24, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_30_2024 Jan 31, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_7_2024 Feb 7, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_14_2024 Feb 14, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_21_2024 Feb 21, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Feb_28_2024 Feb 28, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_6_2024 Mar 6, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_13_2024 Mar 13, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_20_2024 Mar 20, 2024]<br />
<br />
==R30-3 200 kV Gun SAD 2023 Installation Links==<br />
<br />
* ATLIS => https://tasklists.jlab.org/atlis/tasks/108541<br />
* Marcy's Gantt chart goes here => https://jeffersonlab-my.sharepoint.com/:x:/g/personal/marcy_jlab_org/EUe-xbLpNR1IsV28fyi20FUBC4bUllOnMnAYlXemA7C82Q<br />
* List of photocathodes at end of Phase 1 (5/10/2021) - https://logbooks.jlab.org/entry/3876517<br />
<br />
==R30-3 200 kV Gun SAD 2023 Planning Meetings==<br />
<br />
* Feb 20, 2023 => * Carlos SAD schedule [[Media:Gun swap planning 1 week before and 1 week after SAD start.pptx]]<br />
* Feb 02, 2022 => [[Feb 2, 2022 - Group meeting]] - Group meeting + 200 kV gun<br />
* Jan 26, 2022 => [[200 kV Gun - Jan 26, 2022]]<br />
<br />
==Links==<br />
<br />
* [https://wiki.jlab.org/ciswiki/index.php/18%22_Photogun_ala_GTS Carlos 18" Gun Page]<br />
* Gun Anode - Carlos's update https://wiki.jlab.org/ciswiki/index.php/Anode</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_13_2024&diff=30787Mar 13 20242024-03-26T20:25:15Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Cathode front end piece fabrication<br />
** Drawings for option A (16/30 deg) and option B (16/60 deg) have been finalized and submitted to the machine shop<br />
*** [[File:JL0155275, ELECTRODE FRONT END, 16 30.pdf|right|middle|thumb]]<br />
*** [[File:JL0162986, ELECTRODE FRONT END, 16 60.pdf|right|middle|thumb]]<br />
** Matt Poelker provided 316 L Vacuum Arc Re-melt Stainless Steel. Carlos delivered this material to Vince. Carlos to check with Matt supply chain.<br />
** Cathode front end 16-30 test piece was polished using the tumbler barrel. Machining marks on the cone were not fully removed, but piece looks very well polished on the rim.<br />
** This test piece was dry fitted to a spare ball electrode. This piece fits very well as expected.<br />
** [[File:Sample cathode front end piece on sample ball pic02.jpg|left|middle|frameless]]<br />
**[[File:Sample cathode front end piece on sample ball pic05.jpg|left|middle|frameless]]<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_13_2024&diff=30786Mar 13 20242024-03-26T20:24:36Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==Updates==<br />
<br />
* Cathode front end piece fabrication<br />
** Drawings for option A (16/30 deg) and option B (16/60 deg) have been finalized and submitted to the machine shop<br />
*** [[File:JL0155275, ELECTRODE FRONT END, 16 30.pdf|right|middle|thumb]]<br />
*** [[File:JL0162986, ELECTRODE FRONT END, 16 60.pdf|right|middle|thumb]]<br />
** Matt Poelker provided 316 L Vacuum Arc Re-melt Stainless Steel. Carlos delivered this material to Vince. Carlos to check with Matt supply chain.<br />
** Cathode front end 16-30 test piece was polished using the tumbler barrel. Machining marks on the cone were not fully removed, but piece looks very well polished on the rim.<br />
** This test piece was dry fitted to a spare ball electrode. This piece fits very well as expected.<br />
** [[File:Sample cathode front end piece on sample ball pic02.jpg|left|middle|frameless]][[File:Sample cathode front end piece on sample ball pic05.jpg|left|middle|frameless]]<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_13_2024&diff=30785Mar 13 20242024-03-26T20:23:30Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Cathode front end piece fabrication<br />
** Drawings for option A (16/30 deg) and option B (16/60 deg) have been finalized and submitted to the machine shop<br />
*** [[File:JL0155275, ELECTRODE FRONT END, 16 30.pdf|right|middle|thumb]]<br />
*** [[File:JL0162986, ELECTRODE FRONT END, 16 60.pdf|right|middle|thumb]]<br />
** Matt Poelker provided 316 L Vacuum Arc Re-melt Stainless Steel. Carlos delivered this material to Vince. Carlos to check with Matt supply chain.<br />
** Cathode front end 16-30 test piece was polished using the tumbler barrel. Machining marks on the cone were not fully removed, but piece looks very well polished on the rim.<br />
** This test piece was dry fitted to a spare ball electrode. This piece fits very well as expected.<br />
** [[File:Sample cathode front end piece on sample ball pic02.jpg|left|middle|frameless]][[File:Sample cathode front end piece on sample ball pic05.jpg|left|middle|frameless]]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:JL0162986,_ELECTRODE_FRONT_END,_16_60.pdf&diff=30784File:JL0162986, ELECTRODE FRONT END, 16 60.pdf2024-03-26T20:23:28Z<p>Chgarcia: </p>
<hr />
<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_13_2024&diff=30783Mar 13 20242024-03-26T20:22:37Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Cathode front end piece fabrication<br />
** Drawings for option A (16/30 deg) and option B (16/60 deg) have been finalized and submitted to the machine shop<br />
*** [[File:JL0155275, ELECTRODE FRONT END, 16 30.pdf|right|middle|thumb]]<br />
** Matt Poelker provided 316 L Vacuum Arc Re-melt Stainless Steel. Carlos delivered this material to Vince. Carlos to check with Matt supply chain.<br />
** Cathode front end 16-30 test piece was polished using the tumbler barrel. Machining marks on the cone were not fully removed, but piece looks very well polished on the rim.<br />
** This test piece was dry fitted to a spare ball electrode. This piece fits very well as expected.<br />
** [[File:Sample cathode front end piece on sample ball pic02.jpg|left|middle|frameless]][[File:Sample cathode front end piece on sample ball pic05.jpg|left|middle|frameless]]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:JL0155275,_ELECTRODE_FRONT_END,_16_30.pdf&diff=30782File:JL0155275, ELECTRODE FRONT END, 16 30.pdf2024-03-26T20:22:32Z<p>Chgarcia: </p>
<hr />
<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_13_2024&diff=30781Mar 13 20242024-03-26T20:21:00Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Cathode front end piece fabrication<br />
** Drawings for option A (16/30 deg) and option B (16/60 deg) have been finalized and submitted to the machine shop<br />
** Matt Poelker provided 316 L Vacuum Arc Re-melt Stainless Steel. Carlos delivered this material to Vince. Carlos to check with Matt supply chain.<br />
** Cathode front end 16-30 test piece was polished using the tumbler barrel. Machining marks on the cone were not fully removed, but piece looks very well polished on the rim.<br />
** This test piece was dry fitted to a spare ball electrode. This piece fits very well as expected.<br />
** [[File:Sample cathode front end piece on sample ball pic02.jpg|left|middle|frameless]][[File:Sample cathode front end piece on sample ball pic05.jpg|left|middle|frameless]]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:Sample_cathode_front_end_piece_on_sample_ball_pic05.jpg&diff=30780File:Sample cathode front end piece on sample ball pic05.jpg2024-03-26T20:20:57Z<p>Chgarcia: </p>
<hr />
<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:Sample_cathode_front_end_piece_on_sample_ball_pic03.jpg&diff=30779File:Sample cathode front end piece on sample ball pic03.jpg2024-03-26T20:19:50Z<p>Chgarcia: </p>
<hr />
<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_13_2024&diff=30778Mar 13 20242024-03-26T20:17:41Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==Updates==<br />
<br />
* Cathode front end piece fabrication<br />
** Drawings for option A (16/30 deg) and option B (16/60 deg) have been finalized and submitted to the machine shop<br />
** Matt Poelker provided 316 L Vacuum Arc Re-melt Stainless Steel. Carlos delivered this material to Vince. Carlos to check with Matt supply chain.<br />
** Cathode front end 16-30 test piece was polished using the tumbler barrel. Machining marks on the cone were not fully removed, but piece looks very well polished on the rim.<br />
** This test piece was dry fitted to a spare ball electrode. This piece fits very well as expected.<br />
** [[File:Sample cathode front end piece on sample ball pic02.jpg|right|middle|thumb]]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:Sample_cathode_front_end_piece_on_sample_ball_pic02.jpg&diff=30777File:Sample cathode front end piece on sample ball pic02.jpg2024-03-26T20:17:37Z<p>Chgarcia: </p>
<hr />
<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_13_2024&diff=30776Mar 13 20242024-03-26T20:15:08Z<p>Chgarcia: Created page with "==Updates== * Cathode front end piece fabrication ** Drawings for option A (16/30 deg) and option B (16/60 deg) have been finalized and submitted to the machine shop ** Matt..."</p>
<hr />
<div>==Updates==<br />
<br />
* Cathode front end piece fabrication<br />
** Drawings for option A (16/30 deg) and option B (16/60 deg) have been finalized and submitted to the machine shop<br />
** Matt Poelker provided 316 L Vacuum Arc Re-melt Stainless Steel. Carlos delivered this material to Vince. Carlos to check with Matt supply chain.<br />
** Cathode front end 16-30 test piece was polished using the tumbler barrel. Machining marks on the cone were not fully removed, but piece looks very well polished on the rim.<br />
** This test piece was dry fitted to a spare ball electrode. This piece fits very well as expected.</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=200_kV_Polarized_Gun&diff=30775200 kV Polarized Gun2024-03-26T20:11:03Z<p>Chgarcia: /* R30-4 200 kV Gun SAD 2024 Planning Meetings */</p>
<hr />
<div>* The 200 kV gun (R30-3 with spherical electrode and 18" gun HVC) was installed in CEBAF during SAD 2023.<br />
<br />
* This gun performed as designed in terms of vacuum, and high voltage: no field emission at 200 kV after conditioning with Kr to ~240 kV.<br />
* It has two problems:<br />
** The beam waist is ~ 6 cm downstream of the GaAs wafer, compared to ~ 40 cm from the Tee electrode 14" HVC R28-2 gun operated in CEBAF for years at 130 kV.<br />
** It was a not possible to obtain the laser retro-reflection.<br />
* The gun was then removed from the injector and replaced with the R28-2 gun.<br />
* The SAD 2024 links below capture the planning for fixing these problems in the R30-3 gun (which will be version R30-4) and for installing it in May 2024.<br />
<br />
<br />
==R30-4 200 kV Gun SharePoint site==<br />
[https://jeffersonlab.sharepoint.com/:f:/s/CIS/Ejp9S0WdeXtPgFm_bwwkuEAB0gEzYKg7Ci0UfKK8qQnPfQ?e=1tfGAH R30-4 200 kV SharePoint site]<br />
<br />
<br />
Contains:<br />
* Pierce cathode end piece geometry and beam parameter space table<br />
* Notes, studies, and documentation<br />
* Electrostatics and beam dynamics modeling and simulation results<br />
<br />
==R30-4 200 kV Gun SAD 2024 Planning Meetings==<br />
<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_05_2024 Jan 05, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_10_2024 Jan 10,2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_17_2024 Jan 17, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_24_2024 Jan 24, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_30_2024 Jan 31, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_7_2024 Feb 7, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_14_2024 Feb 14, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_21_2024 Feb 21, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Feb_28_2024 Feb 28, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_6_2024 Mar 6, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_13_2024 Mar 13, 2024]<br />
<br />
==R30-3 200 kV Gun SAD 2023 Installation Links==<br />
<br />
* ATLIS => https://tasklists.jlab.org/atlis/tasks/108541<br />
* Marcy's Gantt chart goes here => https://jeffersonlab-my.sharepoint.com/:x:/g/personal/marcy_jlab_org/EUe-xbLpNR1IsV28fyi20FUBC4bUllOnMnAYlXemA7C82Q<br />
* List of photocathodes at end of Phase 1 (5/10/2021) - https://logbooks.jlab.org/entry/3876517<br />
<br />
==R30-3 200 kV Gun SAD 2023 Planning Meetings==<br />
<br />
* Feb 20, 2023 => * Carlos SAD schedule [[Media:Gun swap planning 1 week before and 1 week after SAD start.pptx]]<br />
* Feb 02, 2022 => [[Feb 2, 2022 - Group meeting]] - Group meeting + 200 kV gun<br />
* Jan 26, 2022 => [[200 kV Gun - Jan 26, 2022]]<br />
<br />
==Links==<br />
<br />
* [https://wiki.jlab.org/ciswiki/index.php/18%22_Photogun_ala_GTS Carlos 18" Gun Page]<br />
* Gun Anode - Carlos's update https://wiki.jlab.org/ciswiki/index.php/Anode</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=200_kV_Polarized_Gun&diff=30774200 kV Polarized Gun2024-03-26T20:09:54Z<p>Chgarcia: /* R30-4 200 kV Gun SAD 2024 Planning Meetings */</p>
<hr />
<div>* The 200 kV gun (R30-3 with spherical electrode and 18" gun HVC) was installed in CEBAF during SAD 2023.<br />
<br />
* This gun performed as designed in terms of vacuum, and high voltage: no field emission at 200 kV after conditioning with Kr to ~240 kV.<br />
* It has two problems:<br />
** The beam waist is ~ 6 cm downstream of the GaAs wafer, compared to ~ 40 cm from the Tee electrode 14" HVC R28-2 gun operated in CEBAF for years at 130 kV.<br />
** It was a not possible to obtain the laser retro-reflection.<br />
* The gun was then removed from the injector and replaced with the R28-2 gun.<br />
* The SAD 2024 links below capture the planning for fixing these problems in the R30-3 gun (which will be version R30-4) and for installing it in May 2024.<br />
<br />
<br />
==R30-4 200 kV Gun SharePoint site==<br />
[https://jeffersonlab.sharepoint.com/:f:/s/CIS/Ejp9S0WdeXtPgFm_bwwkuEAB0gEzYKg7Ci0UfKK8qQnPfQ?e=1tfGAH R30-4 200 kV SharePoint site]<br />
<br />
<br />
Contains:<br />
* Pierce cathode end piece geometry and beam parameter space table<br />
* Notes, studies, and documentation<br />
* Electrostatics and beam dynamics modeling and simulation results<br />
<br />
==R30-4 200 kV Gun SAD 2024 Planning Meetings==<br />
<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_05_2024 Jan 05, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_10_2024 Jan 10,2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_17_2024 Jan 17, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_24_2024 Jan 24, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Jan_30_2024 Jan 31, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_7_2024 Feb 7, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_14_2024 Feb 14, 2024]<br />
* >[https://wiki.jlab.org/ciswiki/index.php/Feb_21_2024 Feb 21, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Feb_28_2024 Feb 28, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_6_2024 Mar 6, 2024]<br />
* [https://wiki.jlab.org/ciswiki/index.php/Mar_6_2024 Mar 13, 2024]<br />
<br />
==R30-3 200 kV Gun SAD 2023 Installation Links==<br />
<br />
* ATLIS => https://tasklists.jlab.org/atlis/tasks/108541<br />
* Marcy's Gantt chart goes here => https://jeffersonlab-my.sharepoint.com/:x:/g/personal/marcy_jlab_org/EUe-xbLpNR1IsV28fyi20FUBC4bUllOnMnAYlXemA7C82Q<br />
* List of photocathodes at end of Phase 1 (5/10/2021) - https://logbooks.jlab.org/entry/3876517<br />
<br />
==R30-3 200 kV Gun SAD 2023 Planning Meetings==<br />
<br />
* Feb 20, 2023 => * Carlos SAD schedule [[Media:Gun swap planning 1 week before and 1 week after SAD start.pptx]]<br />
* Feb 02, 2022 => [[Feb 2, 2022 - Group meeting]] - Group meeting + 200 kV gun<br />
* Jan 26, 2022 => [[200 kV Gun - Jan 26, 2022]]<br />
<br />
==Links==<br />
<br />
* [https://wiki.jlab.org/ciswiki/index.php/18%22_Photogun_ala_GTS Carlos 18" Gun Page]<br />
* Gun Anode - Carlos's update https://wiki.jlab.org/ciswiki/index.php/Anode</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_6_2024&diff=30714Mar 6 20242024-03-05T15:58:44Z<p>Chgarcia: </p>
<hr />
<div>==Updates==<br />
<br />
* Max, Gabriel<br />
** Repeated lens optimization for MFX2I01 and MFX1I03 to minimize beam size at MDR1I02 and MWF1I04...<br />
*** R30 16°/30°, SW FX lenses<br />
*** recess +0.1 mm, +0 mm, and -0.1 mm compared to nominal<br />
*** produced lens settings at 0.001 pC and used them at 0.340 pC (similar to machine setup strategy)<br />
*** [[media:Optimized lenses recess comparison.pdf|Comparison of R30 16°/30° lens optimization results]]<br />
*** qualitative shape of curves similar; doing the optimization the other way around would not change the numbers by too much<br />
*** recess affects optimal lens setpoints (unsurprisingly) but causes no unmanageable differences in beam parameters<br />
*** minor emittance increase due to space charge<br />
** Plan B<br />
*** we decided to keep the Plan A Pierce angle but use the junction design from R30-3<br />
*** mitigate risk of field enhancement at junction at the cost of higher surface field on lip<br />
*** Gabriel's material from last time for reference: [[media:R30-4_Junction_angle.pptx|R30-4 junction angle and lip radius gradients vs junction angle]]<br />
*** minor effect on beam: [[media:R30_16_30vs60.pdf|Comparison of R30 16°/30° and 16°/60° focal lengths]]<br />
** Test plan for R28 phase space measurement at CEBAF: https://tasklists.jlab.org/bslist/tasks/111123<br />
*** extends Yan's measurement with option for Twiss-parameter fit<br />
*** perfunctory attempt with R30-3 gun last summer gave excessive emittance, likely due to chromox viewer, but better than nothing?<br />
** Alicia<br />
*** [[media:Comparison_R282_140kV180kVops_settings_scaled_to_200kV_R304_16degPierce30degJunction_beamline_sims_20240303.pdf|140 and 180 kV R28-2 operational settings scaled to 200 kV for R30-4]]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:Comparison_R282_140kV180kVops_settings_scaled_to_200kV_R304_16degPierce30degJunction_beamline_sims_20240303.pdf&diff=30713File:Comparison R282 140kV180kVops settings scaled to 200kV R304 16degPierce30degJunction beamline sims 20240303.pdf2024-03-05T15:58:30Z<p>Chgarcia: </p>
<hr />
<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Mar_6_2024&diff=30712Mar 6 20242024-03-05T15:57:49Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>== Updates ==<br />
<br />
* Max, Gabriel<br />
** Repeated lens optimization for MFX2I01 and MFX1I03 to minimize beam size at MDR1I02 and MWF1I04...<br />
*** R30 16°/30°, SW FX lenses<br />
*** recess +0.1 mm, +0 mm, and -0.1 mm compared to nominal<br />
*** produced lens settings at 0.001 pC and used them at 0.340 pC (similar to machine setup strategy)<br />
*** [[media:Optimized lenses recess comparison.pdf|Comparison of R30 16°/30° lens optimization results]]<br />
*** qualitative shape of curves similar; doing the optimization the other way around would not change the numbers by too much<br />
*** recess affects optimal lens setpoints (unsurprisingly) but causes no unmanageable differences in beam parameters<br />
*** minor emittance increase due to space charge<br />
** Plan B<br />
*** we decided to keep the Plan A Pierce angle but use the junction design from R30-3<br />
*** mitigate risk of field enhancement at junction at the cost of higher surface field on lip<br />
*** Gabriel's material from last time for reference: [[media:R30-4_Junction_angle.pptx|R30-4 junction angle and lip radius gradients vs junction angle]]<br />
*** minor effect on beam: [[media:R30_16_30vs60.pdf|Comparison of R30 16°/30° and 16°/60° focal lengths]]<br />
** Test plan for R28 phase space measurement at CEBAF: https://tasklists.jlab.org/bslist/tasks/111123<br />
*** extends Yan's measurement with option for Twiss-parameter fit<br />
*** perfunctory attempt with R30-3 gun last summer gave excessive emittance, likely due to chromox viewer, but better than nothing?<br />
* Alicia<br />
** [[media:Comparison_R282_140kV180kVops_settings_scaled_to_200kV_R304_16degPierce30degJunction_beamline_sims_20240303.pdf|140 and 180 kV R28-2 operational settings scaled to 200 kV for R30-4]]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Feb_28_2024&diff=30686Feb 28 20242024-02-28T13:52:20Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==From last time==<br />
<br />
* <br />
* Simulations<br />
** Max: <br />
*** Repeat simulations from today's presentation but with space charge ON and with Moller specs bunch charge / beam current. <br />
*** Add dipole field map to simulations.<br />
*** Add to simulations graphics location of first beam viewer screen<br />
*** Continue exploring option B, perhaps with slightly stronger focusing compared to option A(16 deg / 30 deg) Pierce angle cathode front end, but do this with space charge ON and with Moller spec bunch charge<br />
** Alicia: Add emittance to slides from today's presentation<br />
** Yan: Develop beam studies plan (ATLis) to implement BEFORE SAD for measuring beam size at Y-chamber viewer vs first solenoid BDL (or current) for R28 gun operating at 140 kV. Results will then be compared with beam envelope simulation results from Max and from Alicia.<br />
<br />
* ME<br />
** Carlos: <br />
*** Add to schedule fabrication of "plan B' second choice Pierce angle cathode front end. <br />
*** Check actual design and manufacturing progress of plan A (16 deg / 30 deg) Pierce angle cathode front end against schedule.<br />
*** Define milestones and deadlines<br />
* Documentation<br />
** Gabriel: start writing a technical note detailing the process and steps from concept anode-cathode geometry to production of electric field maps and implementation to GPT. Consideration such as puck position wrt to plan of the electrode hole must be described, as well as process for parametric geometry studies including Pierce angle, hole size, junction angle between spherical electrode and front end cathode. Include process for validating CST against POISSON, etc.<br />
<br />
<br />
==Updates==<br />
<br />
* Max:<br />
** 15° dipole simulated and compared with measurement<br />
*** discrepancy in horizontal (de)focusing yet to be understood<br />
*** measured skew coupling likely caused by VIP1I01, planning to mitigate it... could be included in GPT if needed<br />
*** these effects are small compared to the possible variations in gun optics; our not fully understanding them yet is not prohibitive to gun redesign<br />
** optimized lens settings with space charge: [[media:20240227 optimized lenses comparison 200kv.pdf|200 kV, solenoids SW vs. repaired CW]]<br />
*** all four setups are optimized independently for minimum beam sizes in MDR1I02 and MWF1I04<br />
*** beam size/divergence depends on space charge, but optimum BDL for solenoids is only weakly dependent<br />
*** SW solenoids cause emittance exchange due to gun astigmatism, but this gets removed by the second one, no significant difference downstream compared with CW<br />
** design strategy for Plan B electrode driven by possible failure modes: a) beam optics, b) FE / HV breakdown, c) something we are overlooking entirely<br />
*** a) not much freedom to further reduce the Pierce angle without moving the cathode in z, so we're not changing it; no obvious reason to want to increase the focusing strength from nominal<br />
*** b) the only degree of freedom is the junction angle; try to maximize it without exceeding surface-field threshold on lip. Gabriel to provide final numbers<br />
*** c) no idea what to do about this, so fingers crossed<br />
** Gabriel<br />
*** CST simulations looking at the gradient of the lip and junction for various junction angle options.<br />
**** [[media:R30-4 Junction angle.pdf|R30-4 junction angle and lip radius gradients vs junction angle]]<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:R30-4_Junction_angle.pdf&diff=30685File:R30-4 Junction angle.pdf2024-02-28T13:52:10Z<p>Chgarcia: </p>
<hr />
<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Feb_28_2024&diff=30684Feb 28 20242024-02-28T13:51:39Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==From last time==<br />
<br />
* <br />
* Simulations<br />
** Max: <br />
*** Repeat simulations from today's presentation but with space charge ON and with Moller specs bunch charge / beam current. <br />
*** Add dipole field map to simulations.<br />
*** Add to simulations graphics location of first beam viewer screen<br />
*** Continue exploring option B, perhaps with slightly stronger focusing compared to option A(16 deg / 30 deg) Pierce angle cathode front end, but do this with space charge ON and with Moller spec bunch charge<br />
** Alicia: Add emittance to slides from today's presentation<br />
** Yan: Develop beam studies plan (ATLis) to implement BEFORE SAD for measuring beam size at Y-chamber viewer vs first solenoid BDL (or current) for R28 gun operating at 140 kV. Results will then be compared with beam envelope simulation results from Max and from Alicia.<br />
<br />
* ME<br />
** Carlos: <br />
*** Add to schedule fabrication of "plan B' second choice Pierce angle cathode front end. <br />
*** Check actual design and manufacturing progress of plan A (16 deg / 30 deg) Pierce angle cathode front end against schedule.<br />
*** Define milestones and deadlines<br />
* Documentation<br />
** Gabriel: start writing a technical note detailing the process and steps from concept anode-cathode geometry to production of electric field maps and implementation to GPT. Consideration such as puck position wrt to plan of the electrode hole must be described, as well as process for parametric geometry studies including Pierce angle, hole size, junction angle between spherical electrode and front end cathode. Include process for validating CST against POISSON, etc.<br />
<br />
<br />
==Updates==<br />
<br />
* Max:<br />
** 15° dipole simulated and compared with measurement<br />
*** discrepancy in horizontal (de)focusing yet to be understood<br />
*** measured skew coupling likely caused by VIP1I01, planning to mitigate it... could be included in GPT if needed<br />
*** these effects are small compared to the possible variations in gun optics; our not fully understanding them yet is not prohibitive to gun redesign<br />
** optimized lens settings with space charge: [[media:20240227 optimized lenses comparison 200kv.pdf|200 kV, solenoids SW vs. repaired CW]]<br />
*** all four setups are optimized independently for minimum beam sizes in MDR1I02 and MWF1I04<br />
*** beam size/divergence depends on space charge, but optimum BDL for solenoids is only weakly dependent<br />
*** SW solenoids cause emittance exchange due to gun astigmatism, but this gets removed by the second one, no significant difference downstream compared with CW<br />
** design strategy for Plan B electrode driven by possible failure modes: a) beam optics, b) FE / HV breakdown, c) something we are overlooking entirely<br />
*** a) not much freedom to further reduce the Pierce angle without moving the cathode in z, so we're not changing it; no obvious reason to want to increase the focusing strength from nominal<br />
*** b) the only degree of freedom is the junction angle; try to maximize it without exceeding surface-field threshold on lip. Gabriel to provide final numbers<br />
*** c) no idea what to do about this, so fingers crossed<br />
** Gabriel<br />
*** CST simulations looking at the gradient of the lip and junction for various junction angle options.<br />
****[[media:R30-4 Junction angle.pdf|R30-4 junction angle and lip radius gradients vs junction angle]]<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Feb_28_2024&diff=30683Feb 28 20242024-02-28T13:49:21Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==From last time==<br />
<br />
* <br />
* Simulations<br />
** Max: <br />
*** Repeat simulations from today's presentation but with space charge ON and with Moller specs bunch charge / beam current. <br />
*** Add dipole field map to simulations.<br />
*** Add to simulations graphics location of first beam viewer screen<br />
*** Continue exploring option B, perhaps with slightly stronger focusing compared to option A(16 deg / 30 deg) Pierce angle cathode front end, but do this with space charge ON and with Moller spec bunch charge<br />
** Alicia: Add emittance to slides from today's presentation<br />
** Yan: Develop beam studies plan (ATLis) to implement BEFORE SAD for measuring beam size at Y-chamber viewer vs first solenoid BDL (or current) for R28 gun operating at 140 kV. Results will then be compared with beam envelope simulation results from Max and from Alicia.<br />
<br />
* ME<br />
** Carlos: <br />
*** Add to schedule fabrication of "plan B' second choice Pierce angle cathode front end. <br />
*** Check actual design and manufacturing progress of plan A (16 deg / 30 deg) Pierce angle cathode front end against schedule.<br />
*** Define milestones and deadlines<br />
* Documentation<br />
** Gabriel: start writing a technical note detailing the process and steps from concept anode-cathode geometry to production of electric field maps and implementation to GPT. Consideration such as puck position wrt to plan of the electrode hole must be described, as well as process for parametric geometry studies including Pierce angle, hole size, junction angle between spherical electrode and front end cathode. Include process for validating CST against POISSON, etc.<br />
<br />
<br />
==Updates==<br />
<br />
* Max:<br />
** 15° dipole simulated and compared with measurement<br />
*** discrepancy in horizontal (de)focusing yet to be understood<br />
*** measured skew coupling likely caused by VIP1I01, planning to mitigate it... could be included in GPT if needed<br />
*** these effects are small compared to the possible variations in gun optics; our not fully understanding them yet is not prohibitive to gun redesign<br />
** optimized lens settings with space charge: [[media:20240227 optimized lenses comparison 200kv.pdf|200 kV, solenoids SW vs. repaired CW]]<br />
*** all four setups are optimized independently for minimum beam sizes in MDR1I02 and MWF1I04<br />
*** beam size/divergence depends on space charge, but optimum BDL for solenoids is only weakly dependent<br />
*** SW solenoids cause emittance exchange due to gun astigmatism, but this gets removed by the second one, no significant difference downstream compared with CW<br />
** design strategy for Plan B electrode driven by possible failure modes: a) beam optics, b) FE / HV breakdown, c) something we are overlooking entirely<br />
*** a) not much freedom to further reduce the Pierce angle without moving the cathode in z, so we're not changing it; no obvious reason to want to increase the focusing strength from nominal<br />
*** b) the only degree of freedom is the junction angle; try to maximize it without exceeding surface-field threshold on lip. Gabriel to provide final numbers<br />
*** c) no idea what to do about this, so fingers crossed<br />
** Gabriel<br />
*** CST simulations looking at the gradient of the lip and junction for various junction angle options.<br />
****<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Feb_28_2024&diff=30682Feb 28 20242024-02-28T13:46:37Z<p>Chgarcia: /* Updates */</p>
<hr />
<div>==From last time==<br />
<br />
* <br />
* Simulations<br />
** Max: <br />
*** Repeat simulations from today's presentation but with space charge ON and with Moller specs bunch charge / beam current. <br />
*** Add dipole field map to simulations.<br />
*** Add to simulations graphics location of first beam viewer screen<br />
*** Continue exploring option B, perhaps with slightly stronger focusing compared to option A(16 deg / 30 deg) Pierce angle cathode front end, but do this with space charge ON and with Moller spec bunch charge<br />
** Alicia: Add emittance to slides from today's presentation<br />
** Yan: Develop beam studies plan (ATLis) to implement BEFORE SAD for measuring beam size at Y-chamber viewer vs first solenoid BDL (or current) for R28 gun operating at 140 kV. Results will then be compared with beam envelope simulation results from Max and from Alicia.<br />
<br />
* ME<br />
** Carlos: <br />
*** Add to schedule fabrication of "plan B' second choice Pierce angle cathode front end. <br />
*** Check actual design and manufacturing progress of plan A (16 deg / 30 deg) Pierce angle cathode front end against schedule.<br />
*** Define milestones and deadlines<br />
* Documentation<br />
** Gabriel: start writing a technical note detailing the process and steps from concept anode-cathode geometry to production of electric field maps and implementation to GPT. Consideration such as puck position wrt to plan of the electrode hole must be described, as well as process for parametric geometry studies including Pierce angle, hole size, junction angle between spherical electrode and front end cathode. Include process for validating CST against POISSON, etc.<br />
<br />
<br />
==Updates==<br />
<br />
* Max:<br />
** 15° dipole simulated and compared with measurement<br />
*** discrepancy in horizontal (de)focusing yet to be understood<br />
*** measured skew coupling likely caused by VIP1I01, planning to mitigate it... could be included in GPT if needed<br />
*** these effects are small compared to the possible variations in gun optics; our not fully understanding them yet is not prohibitive to gun redesign<br />
** optimized lens settings with space charge: [[media:20240227 optimized lenses comparison 200kv.pdf|200 kV, solenoids SW vs. repaired CW]]<br />
*** all four setups are optimized independently for minimum beam sizes in MDR1I02 and MWF1I04<br />
*** beam size/divergence depends on space charge, but optimum BDL for solenoids is only weakly dependent<br />
*** SW solenoids cause emittance exchange due to gun astigmatism, but this gets removed by the second one, no significant difference downstream compared with CW<br />
** design strategy for Plan B electrode driven by possible failure modes: a) beam optics, b) FE / HV breakdown, c) something we are overlooking entirely<br />
*** a) not much freedom to further reduce the Pierce angle without moving the cathode in z, so we're not changing it; no obvious reason to want to increase the focusing strength from nominal<br />
*** b) the only degree of freedom is the junction angle; try to maximize it without exceeding surface-field threshold on lip. Gabriel to provide final numbers<br />
*** c) no idea what to do about this, so fingers crossed<br />
<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Feb_21_2024&diff=30678Feb 21 20242024-02-22T13:49:41Z<p>Chgarcia: /* Discussion */</p>
<hr />
<div>==From last time==<br />
<br />
* Beam simulations<br />
* ME<br />
** Gabriel provided Keith Harding with 3D model of the new Pierce cathode front end with 16 deg cone and 30 deg junction angle<br />
** They have now a 3D model of the front end piece with the corresponding specs before polishing. This drawing is going to be sent to the machine shop for fabricating two samples. One sample will polished. Then th un-polished and polished samples will be measured (hole diameter) to estimate how much the size increases after polishing. After that the model will be updated and sent back to Gabriel for cross-checking. The expectation is that the dimensions, (particularly hole diameter) after polishing should match the ones of the 3D model used for simulations.<br />
** Machine shop expect to have the two samples ready by end of February.<br />
* Technical Note<br />
** Gabriel to start drafting a procedure for developing electric fields maps in CST starting from ME models and implementing them in GPT<br />
** Max to coordinate the procedure writing with Gabriel and with Alicia to capture steps for model validation with beam-based measurements, and with full injector GPT model<br />
* <br />
<br />
==Discussion==<br />
<br />
* Max's [[media:20240221_Gun_matching.pdf|simulation results]]:<br />
** With optimized solenoid settings for R28 and different R30 cases, all reasonable gun models can be made to behave about the same. The 140 kV settings found this way are only 10% off from what was in the machine during setup with Wiens off.<br />
** Beam size in solenoids: useful lower limit determined by initial emittance and distances; upper limit determined by onset of emittance increase due to aberrations, RMS about 2 mm for CW (!) and 3 mm for SW<br />
*** This means the shorter the focal length (-> less astigmatism + big beam), the better the SW configuration. SW is worse only when Larmor rotation (irrelevant for round beam) causes more effective emittance increase than aberrations. Need to investigate this for a realistic range of beam parameters from the gun.<br />
** Alicia's [[media:Comparison_R282_R304_16degPierce30degJunction_beamline_sims_140kV180kVOps_140kV200kVMax_20240221_v2.pptx|simulation results in Power Point]], [[media:Comparison_R282_R304_16degPierce30degJunction_beamline_sims_140kV180kVOps_140kV200kVMax_20240221_v2.pdf|simulation results in PDF]]<br />
*** Discuss the objectives of the next simulation<br />
<br />
==Path forward, conclusions==<br />
<br />
* <br />
* Simulations<br />
** Max: <br />
*** Repeat simulations from today's presentation but with space charge ON and with Moller specs bunch charge / beam current. <br />
*** Add dipole field map to simulations.<br />
*** Add to simulations graphics location of first beam viewer screen<br />
*** Continue exploring option B, perhaps with slightly stronger focusing compared to option A(16 deg / 30 deg) Pierce angle cathode front end, but do this with space charge ON and with Moller spec bunch charge<br />
** Alicia: Add emittance to slides from today's presentation<br />
** Yan: Develop beam studies plan (ATLis) to implement BEFORE SAD for measuring beam size at Y-chamber viewer vs first solenoid BDL (or current) for R28 gun operating at 140 kV. Results will then be compared with beam envelope simulation results from Max and from Alicia.<br />
<br />
* ME<br />
** Carlos: <br />
*** Add to schedule fabrication of "plan B' second choice Pierce angle cathode front end. <br />
*** Check actual design and manufacturing progress of plan A (16 deg / 30 deg) Pierce angle cathode front end against schedule.<br />
*** Define milestones and deadlines<br />
* Documentation<br />
** Gabriel: start writing a technical note detailing the process and steps from concept anode-cathode geometry to production of electric field maps and implementation to GPT. Consideration such as puck position wrt to plan of the electrode hole must be described, as well as process for parametric geometry studies including Pierce angle, hole size, junction angle between spherical electrode and front end cathode. Include process for validating CST against POISSON, etc.<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=File:Comparison_R282_R304_16degPierce30degJunction_beamline_sims_140kV180kVOps_140kV200kVMax_20240221_v2.pdf&diff=30677File:Comparison R282 R304 16degPierce30degJunction beamline sims 140kV180kVOps 140kV200kVMax 20240221 v2.pdf2024-02-22T13:49:24Z<p>Chgarcia: </p>
<hr />
<div></div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Feb_21_2024&diff=30676Feb 21 20242024-02-22T13:48:14Z<p>Chgarcia: /* Discussion */</p>
<hr />
<div>==From last time==<br />
<br />
* Beam simulations<br />
* ME<br />
** Gabriel provided Keith Harding with 3D model of the new Pierce cathode front end with 16 deg cone and 30 deg junction angle<br />
** They have now a 3D model of the front end piece with the corresponding specs before polishing. This drawing is going to be sent to the machine shop for fabricating two samples. One sample will polished. Then th un-polished and polished samples will be measured (hole diameter) to estimate how much the size increases after polishing. After that the model will be updated and sent back to Gabriel for cross-checking. The expectation is that the dimensions, (particularly hole diameter) after polishing should match the ones of the 3D model used for simulations.<br />
** Machine shop expect to have the two samples ready by end of February.<br />
* Technical Note<br />
** Gabriel to start drafting a procedure for developing electric fields maps in CST starting from ME models and implementing them in GPT<br />
** Max to coordinate the procedure writing with Gabriel and with Alicia to capture steps for model validation with beam-based measurements, and with full injector GPT model<br />
* <br />
<br />
==Discussion==<br />
<br />
* Max's [[media:20240221_Gun_matching.pdf|simulation results]]:<br />
** With optimized solenoid settings for R28 and different R30 cases, all reasonable gun models can be made to behave about the same. The 140 kV settings found this way are only 10% off from what was in the machine during setup with Wiens off.<br />
** Beam size in solenoids: useful lower limit determined by initial emittance and distances; upper limit determined by onset of emittance increase due to aberrations, RMS about 2 mm for CW (!) and 3 mm for SW<br />
*** This means the shorter the focal length (-> less astigmatism + big beam), the better the SW configuration. SW is worse only when Larmor rotation (irrelevant for round beam) causes more effective emittance increase than aberrations. Need to investigate this for a realistic range of beam parameters from the gun.<br />
* Alicia's [[media:Comparison_R282_R304_16degPierce30degJunction_beamline_sims_140kV180kVOps_140kV200kVMax_20240221_v2.pptx|simulation results in Power Point]], [[media:Comparison_R282_R304_16degPierce30degJunction_beamline_sims_140kV180kVOps_140kV200kVMax_20240221_v2.pdf|simulation results in PDF]]<br />
** Discuss the objectives of the next simulation<br />
<br />
==Path forward, conclusions==<br />
<br />
* <br />
* Simulations<br />
** Max: <br />
*** Repeat simulations from today's presentation but with space charge ON and with Moller specs bunch charge / beam current. <br />
*** Add dipole field map to simulations.<br />
*** Add to simulations graphics location of first beam viewer screen<br />
*** Continue exploring option B, perhaps with slightly stronger focusing compared to option A(16 deg / 30 deg) Pierce angle cathode front end, but do this with space charge ON and with Moller spec bunch charge<br />
** Alicia: Add emittance to slides from today's presentation<br />
** Yan: Develop beam studies plan (ATLis) to implement BEFORE SAD for measuring beam size at Y-chamber viewer vs first solenoid BDL (or current) for R28 gun operating at 140 kV. Results will then be compared with beam envelope simulation results from Max and from Alicia.<br />
<br />
* ME<br />
** Carlos: <br />
*** Add to schedule fabrication of "plan B' second choice Pierce angle cathode front end. <br />
*** Check actual design and manufacturing progress of plan A (16 deg / 30 deg) Pierce angle cathode front end against schedule.<br />
*** Define milestones and deadlines<br />
* Documentation<br />
** Gabriel: start writing a technical note detailing the process and steps from concept anode-cathode geometry to production of electric field maps and implementation to GPT. Consideration such as puck position wrt to plan of the electrode hole must be described, as well as process for parametric geometry studies including Pierce angle, hole size, junction angle between spherical electrode and front end cathode. Include process for validating CST against POISSON, etc.<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarciahttps://wiki.jlab.org/ciswiki/index.php?title=Feb_21_2024&diff=30675Feb 21 20242024-02-22T13:47:36Z<p>Chgarcia: /* Discussion */</p>
<hr />
<div>==From last time==<br />
<br />
* Beam simulations<br />
* ME<br />
** Gabriel provided Keith Harding with 3D model of the new Pierce cathode front end with 16 deg cone and 30 deg junction angle<br />
** They have now a 3D model of the front end piece with the corresponding specs before polishing. This drawing is going to be sent to the machine shop for fabricating two samples. One sample will polished. Then th un-polished and polished samples will be measured (hole diameter) to estimate how much the size increases after polishing. After that the model will be updated and sent back to Gabriel for cross-checking. The expectation is that the dimensions, (particularly hole diameter) after polishing should match the ones of the 3D model used for simulations.<br />
** Machine shop expect to have the two samples ready by end of February.<br />
* Technical Note<br />
** Gabriel to start drafting a procedure for developing electric fields maps in CST starting from ME models and implementing them in GPT<br />
** Max to coordinate the procedure writing with Gabriel and with Alicia to capture steps for model validation with beam-based measurements, and with full injector GPT model<br />
* <br />
<br />
==Discussion==<br />
<br />
* Max's [[media:20240221_Gun_matching.pdf|simulation results]]:<br />
** With optimized solenoid settings for R28 and different R30 cases, all reasonable gun models can be made to behave about the same. The 140 kV settings found this way are only 10% off from what was in the machine during setup with Wiens off.<br />
** Beam size in solenoids: useful lower limit determined by initial emittance and distances; upper limit determined by onset of emittance increase due to aberrations, RMS about 2 mm for CW (!) and 3 mm for SW<br />
*** This means the shorter the focal length (-> less astigmatism + big beam), the better the SW configuration. SW is worse only when Larmor rotation (irrelevant for round beam) causes more effective emittance increase than aberrations. Need to investigate this for a realistic range of beam parameters from the gun.<br />
* Alicia's [[media:Comparison_R282_R304_16degPierce30degJunction_beamline_sims_140kV180kVOps_140kV200kVMax_20240221_v2.pptx|simulation results in Power Point]]<br />
** Discuss the objectives of the next simulation<br />
<br />
==Path forward, conclusions==<br />
<br />
* <br />
* Simulations<br />
** Max: <br />
*** Repeat simulations from today's presentation but with space charge ON and with Moller specs bunch charge / beam current. <br />
*** Add dipole field map to simulations.<br />
*** Add to simulations graphics location of first beam viewer screen<br />
*** Continue exploring option B, perhaps with slightly stronger focusing compared to option A(16 deg / 30 deg) Pierce angle cathode front end, but do this with space charge ON and with Moller spec bunch charge<br />
** Alicia: Add emittance to slides from today's presentation<br />
** Yan: Develop beam studies plan (ATLis) to implement BEFORE SAD for measuring beam size at Y-chamber viewer vs first solenoid BDL (or current) for R28 gun operating at 140 kV. Results will then be compared with beam envelope simulation results from Max and from Alicia.<br />
<br />
* ME<br />
** Carlos: <br />
*** Add to schedule fabrication of "plan B' second choice Pierce angle cathode front end. <br />
*** Check actual design and manufacturing progress of plan A (16 deg / 30 deg) Pierce angle cathode front end against schedule.<br />
*** Define milestones and deadlines<br />
* Documentation<br />
** Gabriel: start writing a technical note detailing the process and steps from concept anode-cathode geometry to production of electric field maps and implementation to GPT. Consideration such as puck position wrt to plan of the electrode hole must be described, as well as process for parametric geometry studies including Pierce angle, hole size, junction angle between spherical electrode and front end cathode. Include process for validating CST against POISSON, etc.<br />
<br />
=<br />=<br />
[https://wiki.jlab.org/ciswiki/index.php/200_kV_Polarized_Gun Return to 200 kV Gun page]</div>Chgarcia