{"id":1908,"date":"2020-03-17T00:08:36","date_gmt":"2020-03-17T04:08:36","guid":{"rendered":"http:\/\/www.nuclearphysicslab.com\/npl\/?page_id=1908"},"modified":"2020-03-18T14:19:14","modified_gmt":"2020-03-18T18:19:14","slug":"first-beam-attempts","status":"publish","type":"page","link":"http:\/\/www.nuclearphysicslab.com\/npl\/npl-home\/accelerators\/betatrons\/first-beam-attempts\/","title":{"rendered":"First Beam Attempts"},"content":{"rendered":"\n<p class=\"has-text-align-center\"><em>Author: Tim<\/em><\/p>\n\n\n\n<p>The first beam attempts showed no run away electron beam action, which has led to a campaign to measure the magnetic field &#8211; this is still ongoing.  However, fast imaging has revealed an interesting plasma instability that was not present in the straight pinch experiments.  <\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"4256\" height=\"2832\" src=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/2017j.jpg\" alt=\"\" class=\"wp-image-1909\" srcset=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/2017j.jpg 4256w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/2017j-768x511.jpg 768w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/2017j-1536x1022.jpg 1536w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/2017j-2048x1363.jpg 2048w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/2017j-406x270.jpg 406w\" sizes=\"(max-width: 4256px) 100vw, 4256px\" \/><figcaption>Tim overlooking a high-pressure plasma pulse.<\/figcaption><\/figure>\n\n\n\n<p>The following two photos are frames from the first hybrid attempts to pinch and accelerate beam in the plasma betatron.  These two images are from two different shots. Each frame&#8217;s exposure time is 100ns.  The two images are separated by 200ns. <\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"1024\" height=\"1024\" src=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15524_1.jpg\" alt=\"\" class=\"wp-image-2029\" srcset=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15524_1.jpg 1024w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15524_1-500x500.jpg 500w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15524_1-768x768.jpg 768w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15524_1-270x270.jpg 270w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption>Single frame, 100ns long from fast cine imaging, inside betatron coil.<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"1024\" height=\"1024\" src=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15526_1.jpg\" alt=\"\" class=\"wp-image-2030\" srcset=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15526_1.jpg 1024w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15526_1-500x500.jpg 500w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15526_1-768x768.jpg 768w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch_pos15526_1-270x270.jpg 270w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><figcaption>Single frame, 100ns long from fast cine imaging, 200ns after above frame, inside betatron coil.<\/figcaption><\/figure>\n\n\n\n<p>We have taken roughly one hundred such shots, each of 100ns exposure time.  The image of each subsequent shot was delayed by 100ns from the previous.  The images were then stitched together to form a cine-movie.<\/p>\n\n\n\n<figure class=\"wp-block-embed-vimeo wp-block-embed is-type-video is-provider-vimeo wp-embed-aspect-1-1 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"Jan_17_2018_Kr_PBrun_3_5loop_gray_ver2.avi\" src=\"https:\/\/player.vimeo.com\/video\/397870670?dnt=1&amp;app_id=122963\" width=\"640\" height=\"638\" frameborder=\"0\" allow=\"autoplay; fullscreen\" allowfullscreen><\/iframe>\n<\/div><\/figure>\n\n\n\n<p>Contrast the above images with the more successful straight pinch (no betatron field).<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"1024\" height=\"1024\" src=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch.jpg\" alt=\"\" class=\"wp-image-798\" srcset=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch.jpg 1024w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch-500x500.jpg 500w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch-768x768.jpg 768w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/pinch-270x270.jpg 270w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p>The instability is still mystery.  It is assumed to be from the ExB forces where the B-field has a strong gradient.  To assist with stability, azimuthal coils have been wound around the toroid.  More about that project in a subsequent post, but here are a few photos of the azimuthal field coils.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"4032\" height=\"3024\" src=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5292.jpg\" alt=\"\" class=\"wp-image-2034\" srcset=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5292.jpg 4032w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5292-768x576.jpg 768w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5292-1536x1152.jpg 1536w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5292-2048x1536.jpg 2048w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5292-360x270.jpg 360w\" sizes=\"(max-width: 4032px) 100vw, 4032px\" \/><figcaption>Twelve hand-wound coils equally spaced.  Each coil has 50 turns over the course of four layers. The coils are wired in series for a total of 600 turns.<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"3024\" height=\"4032\" src=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5316-rotated.jpg\" alt=\"\" class=\"wp-image-2035\" srcset=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5316-rotated.jpg 3024w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5316-1875x2500.jpg 1875w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5316-768x1024.jpg 768w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5316-1152x1536.jpg 1152w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5316-1536x2048.jpg 1536w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/IMG_5316-203x270.jpg 203w\" sizes=\"(max-width: 3024px) 100vw, 3024px\" \/><figcaption>RF pre-ionzation with coils energized.<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"4256\" height=\"2832\" src=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_6820.jpg\" alt=\"\" class=\"wp-image-2036\" srcset=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_6820.jpg 4256w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_6820-768x511.jpg 768w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_6820-1536x1022.jpg 1536w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_6820-2048x1363.jpg 2048w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_6820-406x270.jpg 406w\" sizes=\"(max-width: 4256px) 100vw, 4256px\" \/><figcaption>Betatron pulse without the coils energized (to protect the azimuthal coil power supply)<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"4256\" height=\"2832\" src=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7307.jpg\" alt=\"\" class=\"wp-image-2037\" srcset=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7307.jpg 4256w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7307-768x511.jpg 768w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7307-1536x1022.jpg 1536w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7307-2048x1363.jpg 2048w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7307-406x270.jpg 406w\" sizes=\"(max-width: 4256px) 100vw, 4256px\" \/><figcaption>Top view through mirror view<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" width=\"4256\" height=\"2832\" src=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7310.jpg\" alt=\"\" class=\"wp-image-2038\" srcset=\"http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7310.jpg 4256w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7310-768x511.jpg 768w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7310-1536x1022.jpg 1536w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7310-2048x1363.jpg 2048w, http:\/\/www.nuclearphysicslab.com\/npl\/wp-content\/uploads\/TIM_7310-406x270.jpg 406w\" sizes=\"(max-width: 4256px) 100vw, 4256px\" \/><figcaption>Pulse: top view through mirror of betatron pulse without the coils energized (to protect the azimuthal coil power supply)<\/figcaption><\/figure>\n\n\n\n<p>Next post will focus on the azimuthal coil impact.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Author: Tim The first beam attempts showed no run away electron beam action, which has led to a campaign to measure the magnetic field &#8211; this is still ongoing. However, fast imaging has revealed an interesting plasma instability that was not present in the straight pinch experiments. The following two photos are frames from&#8230;<\/p>\n<p class=\"read-more\"><a class=\"btn btn-default\" href=\"http:\/\/www.nuclearphysicslab.com\/npl\/npl-home\/accelerators\/betatrons\/first-beam-attempts\/\"> Read More<span class=\"screen-reader-text\">  Read More<\/span><\/a><\/p>\n","protected":false},"author":3,"featured_media":2036,"parent":151,"menu_order":3,"comment_status":"closed","ping_status":"closed","template":"","meta":{"advanced-sidebar-menu\/link-title":"","advanced-sidebar-menu\/exclude-page":false},"categories":[10,14,78,37],"tags":[],"_links":{"self":[{"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/pages\/1908"}],"collection":[{"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/comments?post=1908"}],"version-history":[{"count":5,"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/pages\/1908\/revisions"}],"predecessor-version":[{"id":2125,"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/pages\/1908\/revisions\/2125"}],"up":[{"embeddable":true,"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/pages\/151"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/media\/2036"}],"wp:attachment":[{"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/media?parent=1908"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/categories?post=1908"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.nuclearphysicslab.com\/npl\/wp-json\/wp\/v2\/tags?post=1908"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}