{"id":19462,"date":"2022-01-26T11:56:15","date_gmt":"2022-01-26T03:56:15","guid":{"rendered":"https:\/\/www.whatchina.cn\/?p=19462"},"modified":"2022-01-26T13:33:01","modified_gmt":"2022-01-26T05:33:01","slug":"jinping-underground-laboratory","status":"publish","type":"post","link":"https:\/\/www.whatchina.cn\/jinping-underground-laboratory.html","title":{"rendered":"China Jinping Underground Laboratory"},"content":{"rendered":"<div class=\"37c28470d9d6d3cb9ff74e663adb766a\" data-index=\"2\" style=\"float: none; margin:0px 0 0px 0; text-align:center;\">\n<script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3594734025006597\"\r\n     crossorigin=\"anonymous\"><\/script>\n<\/div>\n<p>China&#8217;s first extremely deep underground laboratory &#8211; &#8220;<a href=\"https:\/\/www.tsinghua.edu.cn\/info\/1363\/80892.htm\" target=\"_blank\" rel=\"nofollow noopener\">China Jinping Underground Laboratory<\/a>&#8221; was unveiled and put into use at the Jinping Hydropower Station on the Yalong River in Sichuan on December 12, 2010. The vertical rock coverage of the Jinping underground laboratory reaches 2,400 meters, which is the world&#8217;s rock Covers the deepest labs. Its completion marks that China already has a world-class clean low-radiation research platform and can independently carry out the most cutting-edge international basic research topics such as dark matter detection. The dark matter detector of the experimental group of Tsinghua University has taken the lead in entering the laboratory and started the detection work. In 2011, research teams such as Shanghai Jiaotong University also entered here to carry out dark matter detection research.<br \/>\nChina Jinping underground laboratory is about to expand, from 4,000 cubic meters to 120,000 cubic meters. In June 2018, the China Dark Matter Experiment Cooperation Group used an internationally pioneered high-purity germanium detection system to increase the direct detection sensitivity of dark matter to the highest international level within a certain range.<img decoding=\"async\" class=\"aligncenter size-full wp-image-19463\" src=\"https:\/\/www.whatchina.cn\/wp-content\/uploads\/2022\/01\/China-Jinping-Underground-Laboratory.jpg\" alt=\"China Jinping Underground Laboratory\" width=\"640\" height=\"400\" srcset=\"https:\/\/www.whatchina.cn\/wp-content\/uploads\/2022\/01\/China-Jinping-Underground-Laboratory.jpg 640w, https:\/\/www.whatchina.cn\/wp-content\/uploads\/2022\/01\/China-Jinping-Underground-Laboratory-300x188.jpg 300w\" sizes=\"(max-width: 640px) 100vw, 640px\" \/><\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_73 counter-flat ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.whatchina.cn\/jinping-underground-laboratory.html\/#Composition_structure\" title=\"Composition structure\">Composition structure<\/a><\/li><li class='ez-toc-page-1'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.whatchina.cn\/jinping-underground-laboratory.html\/#Technical_principles\" title=\"Technical principles\">Technical principles<\/a><\/li><li class='ez-toc-page-1'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.whatchina.cn\/jinping-underground-laboratory.html\/#Detection_method\" title=\"Detection method\">Detection method<\/a><\/li><li class='ez-toc-page-1'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.whatchina.cn\/jinping-underground-laboratory.html\/#Reason_for_location\" title=\"Reason for location\">Reason for location<\/a><\/li><li class='ez-toc-page-1'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.whatchina.cn\/jinping-underground-laboratory.html\/#R_D_progress\" title=\"R&amp;D progress\">R&amp;D progress<\/a><\/li><li class='ez-toc-page-1'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.whatchina.cn\/jinping-underground-laboratory.html\/#Latest_News\" title=\"Latest News\">Latest News<\/a><\/li><\/ul><\/nav><\/div>\n<h3><span class=\"ez-toc-section\" id=\"Composition_structure\"><\/span><strong>Composition structure<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The &#8220;China Jinping Underground Laboratory&#8221; was built using the Jinping Mountain Tunnel built for the hydropower station. Its vertical rock cover reaches 2,400 meters, making it the deepest rock-covered underground laboratory in the world. By comparison, the European underground laboratory in the mountains of Gran Sasso in central Italy is like a playroom. Under the mountains of Sichuan and Tibet, the intensity of cosmic rays that particle physicists are most troubled by is only 1\/200 of that in the mountains of Gran Sasso, providing a &#8220;clean&#8221; environment for experiments.<br \/>\nConnecting the 17.6-kilometer traffic tunnel where Jinping I and Jinping II hydropower stations are located, there is a mountain rock with a thickness of more than 2,500 meters. This will be the first experiment after the establishment of the institute, dedicated to &#8220;hunting&#8221; dark matter. This is the best environment in the world to detect dark matter.<br \/>\nThe laboratory uses the underground tunnel built when the local <a title=\"The Three Gorges Project Sets A World Record For Annual Power Generation From A Single Hydropower Station\" href=\"https:\/\/www.whatchina.cn\/the-three-gorges-project-sets-a-world-record-for-annual-power-generation-from-a-single-hydropower-station.html\">hydropower station<\/a> was built, and a space of 40 meters in length, 6 meters in width and 6 meters in height is excavated on the side of the tunnel. Therefore, compared with some foreign underground laboratories that are &#8220;born out&#8221; of mines, it is more convenient to use the tunnels with a depth of 2,500 meters, because the deeper they are buried, the less interference from cosmic rays.<br \/>\nThe underground laboratory is an important research site for major fundamental frontier topics such as dark matter detection and neutrino experiments in the fields of particle physics and astrophysics. The high-purity germanium detector used in the laboratory requires not only cutting-edge technology but also a lot of capital investment.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Technical_principles\"><\/span><strong>Technical principles<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>In cosmology, dark matter refers to matter that does not emit any light or electromagnetic radiation. One can only know that there is a large amount of dark matter in the universe through the effects of gravity. The earliest evidence for the existence of dark matter came from observations of the rotational speed of spherical galaxies. Modern astronomy has shown through gravitational lensing, the formation of large-scale structures in the universe, microwave background radiation and other studies that the part we know only accounts for about 4% of the universe, dark matter accounts for 23% of the universe, and 73% is a cause of The dark energy of the accelerating expansion of the universe.<br \/>\nThe original method was the astronomical observation method, but it could not answer &#8220;what is dark matter&#8221;. Later, people adopted indirect detection and direct detection methods. The former is to detect the signal of ordinary matter particles produced by the collision of dark matter, which is generally detected by ground or space telescopes; the latter is to use the collision of atomic nuclei and dark matter to detect the signal generated by the collision. On the ground, because of the large number of cosmic rays, these signals will interfere with direct detection and affect its identification ability. Therefore, the construction of the underground laboratory can help the detector to &#8220;block&#8221; the interference and let it work &#8220;quietly&#8221;.<br \/>\nBecause dark matter is a kind of &#8220;personal&#8221; particle in the universe, it has a large mass, but its force is very small. &#8220;There may be trillions of dark matter passing through your body every day, but you can&#8217;t feel it, because the scattering cross section of dark matter is very small.&#8221; Experts say that this is like a football that can be caught by a net. Block, but a small iron ball can pass through the net because its cross section is smaller than the mesh of the ball net.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Detection_method\"><\/span><strong>Detection method<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>&#8220;It takes about 20 minutes to drive from the ground to the underground laboratory. Once the instrument is stable, he only needs to monitor the operation of the detector in the office on the ground, and all the data from the underground laboratory will be transmitted to the ground, Therefore, researchers do not need to &#8220;guard&#8221; the detector 24 hours a day.<br \/>\nTwo experimental groups from Tsinghua University and Shanghai Jiaotong University have settled in the underground laboratory. The dark matter detector of Tsinghua University has taken the lead in entering the laboratory and started detection work. In 2011, research teams such as Shanghai Jiaotong University will also enter here to carry out dark matter detection research. The detection methods of the two experimental groups are different. Shanghai Jiaotong University will use liquid xenon detectors to carry out direct detection of dark matter here, and Tsinghua University will use low-temperature semiconductors to carry out detection. In the process, every scientific discovery will advance our understanding of the physical world. Gong Min said that Sichuan University will cooperate with Tsinghua University to join the dark matter research topic.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Reason_for_location\"><\/span><strong>Reason for location<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The location of the Jinping Mountain Tunnel is because the Jinping Mountain has the greatest geographical advantage of vertical rock coverage. The laboratory is excavated from the side of the tunnel, 40 meters long, 6 meters wide and 6 meters high. It is buried deep underground. on level ground. All kinds of equipment, detectors, ventilation equipment, etc. in the laboratory are very good, and all the data in the underground laboratory are transmitted to the ground.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"R_D_progress\"><\/span><strong>R&amp;D progress<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>According to data, many countries such as the United States, Britain, France, Italy, Canada, and Japan have established underground laboratories. As early as 2009, the United States also established an underground laboratory with a depth of about 2,438 meters in Black Mountain, South Dakota. Japan also built the XMASS underground laboratory in October 2010 under the Kamioka Mine in Tobi City, Gifu Prefecture. An underground laboratory up to 350 meters deep in the UK was also launched in April 2010. Its purpose is to hope to be the first country in the world to discover dark matter.<br \/>\nExperts say particle physics explores the deepest mysteries of matter. Just like when electricity was invented, people can&#8217;t imagine the TV and computers that will come later. But in any case, every scientific discovery advances our understanding of the physical world.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Latest_News\"><\/span><strong>Latest News<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>On August 1, 2014, Tsinghua University and Yalong River Basin Hydropower Development Co., Ltd. signed a cooperation agreement in Chengdu to jointly build the second phase of the &#8220;China Jinping Underground Laboratory&#8221;, and officially decided to start the China Jinping Underground Laboratory, including 4 groups The second-phase construction of a total of 8 laboratories and their auxiliary facilities has once again attracted worldwide attention.<br \/>\nThe China Dark Matter Experiment Cooperation Group has carried out direct detection of dark matter in the Jinping Underground Laboratory of China since 2010. The second stage of the CDEX-10 experiment has been carried out. The China Dark Matter Experiment Cooperation Group has used an internationally pioneered high-purity germanium detection system. Raise the sensitivity of direct detection of dark matter to the highest level in the world within a certain range. Relevant research results have been published online in the top international physics journal &#8220;Physical Review Letters&#8221;. This experimental result is the first physical result of the CDEX-10 experiment.<br \/>\nZhou Yufeng, a researcher at the Institute of Theoretical Physics, Chinese Academy of Sciences, who has been engaged in dark matter theory research for a long time, believes that the China Dark Matter Experiment Collaboration (CDEX) uses a unique high-purity germanium detection system to give dark matter self-confidence in the energy range of 4-5 gigaelectron volts. The latest upper limit of the spin-independent scattering cross section, which is the world&#8217;s best result in this energy region that has been officially published.<br \/>\nAccording to Yue Qian, the corresponding author of the paper and a professor at the Department of Engineering Physics of Tsinghua University, high-purity germanium is a very high-purity semiconductor material. Several international experimental groups have used high-purity germanium crystals as target materials and detectors for direct detection of dark matter experiments.<br \/>\nOn July 24, 2019, the construction of a major national science and technology infrastructure project was officially launched. This project will provide the best international platform support for major frontier deep scientific experiments such as dark matter.<\/p>\n<div class=\"37c28470d9d6d3cb9ff74e663adb766a\" data-index=\"2\" style=\"float: none; margin:0px 0 0px 0; text-align:center;\">\n<script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-3594734025006597\"\r\n     crossorigin=\"anonymous\"><\/script>\n<\/div>\n\n<div style=\"font-size: 0px; height: 0px; line-height: 0px; margin: 0; padding: 0; clear: both;\"><\/div>","protected":false},"excerpt":{"rendered":"<p>China&#8217;s first extremely deep underground laboratory &#8211; &#8220;China Jinping Underground Laboratory&#8221; was unveiled and put&#8230;<\/p>\n","protected":false},"author":1,"featured_media":19463,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ngg_post_thumbnail":0,"footnotes":""},"categories":[84],"tags":[2253,2254,2252],"class_list":["post-19462","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","tag-china-underground-laboratory","tag-jinping-underground-laboratory","tag-underground-laboratory"],"_links":{"self":[{"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/posts\/19462","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/comments?post=19462"}],"version-history":[{"count":0,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/posts\/19462\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/media\/19463"}],"wp:attachment":[{"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/media?parent=19462"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/categories?post=19462"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.whatchina.cn\/wp-json\/wp\/v2\/tags?post=19462"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}