{"id":456,"date":"2025-10-11T10:02:26","date_gmt":"2025-10-11T02:02:26","guid":{"rendered":"http:\/\/web.tdli.sjtu.edu.cn\/kunliu\/?page_id=456"},"modified":"2025-10-11T10:02:26","modified_gmt":"2025-10-11T02:02:26","slug":"research","status":"publish","type":"page","link":"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/research\/","title":{"rendered":"RESEARCH"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">Higgs physics in ATLAS experiment <\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"514\" src=\"http:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-5.53.25-PM-1024x514.png\" alt=\"\" class=\"wp-image-161\" srcset=\"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-5.53.25-PM-1024x514.png 1024w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-5.53.25-PM-300x151.png 300w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-5.53.25-PM-768x385.png 768w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-5.53.25-PM-1536x771.png 1536w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-5.53.25-PM-2048x1028.png 2048w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-5.53.25-PM-624x313.png 624w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"has-drop-cap has-text-align-left\">Higgs boson discovery in 2012 at the LHC [<a rel=\"noreferrer noopener\" href=\"https:\/\/atlas.cern\/updates\/press-statement\/latest-results-atlas-higgs-search\" target=\"_blank\">1<\/a>,<a rel=\"noreferrer noopener\" href=\"https:\/\/atlas.cern\/updates\/press-statement\/latest-results-atlas-higgs-search\" target=\"_blank\">2<\/a>] completed the Standard Model of particle physics. Measurement of this newly discovered Higgs boson properties examines the SM electroweak theory, and would also shed light for physics in beyond. For more details, please find my [<a rel=\"noreferrer noopener\" href=\"https:\/\/indico-tdli.sjtu.edu.cn\/event\/1013\/contributions\/4047\/attachments\/1952\/2986\/HiggsPhysics-KunLiu.pdf\" target=\"_blank\">talk<\/a>] and [<a href=\"https:\/\/vshare.sjtu.edu.cn\/open\/7f46cd96964402744b8215c98803ef18\">video record<\/a>] at the Joint TDLI and INPAC Summer School on Particle Physics 2022. <\/p>\n\n\n\n<p class=\"has-drop-cap has-text-align-left\">Currently I am working on the following analysis topics: <\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Search for Higgs production in association with top quark pair. This channel allows a direct measurement of Higgs-top Yukawa coupling parameter. This parameter is close to unity, any deviation is hint for new physics. It is also sensitive to setting upper limit on energy scale of New phyiscs[<a rel=\"noreferrer noopener\" href=\"https:\/\/arxiv.org\/abs\/1411.1923\" target=\"_blank\">3<\/a>]; <\/li><li>Search for Higgs pair production. Within the Standard Model, non-resonant di-Higgs production provides access to the Higgs tri-linear self-coupling, providing a key test of the Higgs mechanism. Beyond the Standard Model, both resonant and non-resonant di-Higgs production are sensitive to extended Higgs sectors and their implications for a possible first order electroweak phase transition in the early universe.<\/li><li>Combined measurements of Higgs properties. Precision measurement of Higgs properties is one of the major goals at the Large Hadron Collider and the future colliders. It plays leading role in the SM examination, and sheds lights on physics beyond the SM. Combining all Higgs analysis channels at the LHC has the highest measurement precision, before the next generation collider commissioning.<\/li><\/ul>\n\n\n\n<p class=\"has-text-align-left\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Direct search for light Dark Matter candiates<\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"525\" src=\"http:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-6.03.23-PM-1024x525.png\" alt=\"\" class=\"wp-image-163\" srcset=\"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-6.03.23-PM-1024x525.png 1024w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-6.03.23-PM-300x154.png 300w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-6.03.23-PM-768x394.png 768w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-6.03.23-PM-1536x788.png 1536w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-6.03.23-PM-2048x1050.png 2048w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2021\/07\/Screen-Shot-2021-07-03-at-6.03.23-PM-624x320.png 624w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"has-drop-cap\">Dark Matter(DM) plays a central role in our understanding of modern cosmology. The presence of DM is motivated by gravitational physics, there is big hope that the DM particles may interact with other DM particles via a new dark force, similar to the electromagnetic force felt by ordinary matter. In this case one can expect there to be a dark photon that mediates this dark force, in analogy to the ordinary photon of electromagnetism. We are investigating the possibility of searching for dark photon candidate using high frequency electrons from the SHINE facility. For more details, please find my [<a href=\"https:\/\/indico-tdli.sjtu.edu.cn\/event\/1013\/contributions\/4045\/attachments\/1970\/3295\/DarkPhotonExperiment.pdf\" target=\"_blank\" rel=\"noreferrer noopener\">talk<\/a>] and [<a href=\"https:\/\/vshare.sjtu.edu.cn\/open\/aff8cd51f6685cd2ca5fd9d94ef619e5\" target=\"_blank\" rel=\"noreferrer noopener\">video record<\/a>] at the Joint TDLI and INPAC Summer School on Particle Physics 2022.<\/p>\n\n\n\n<h2 class=\"has-dark-gray-color has-text-color wp-block-heading\">Silicon semiconductor detector R&amp;D (Tracker Lab. @ TDLI Building  Room S244)<\/h2>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"2268\" height=\"3402\" src=\"http:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2023\/05\/\u7406\u79d1\u697c6\u53f7\u697c111.png\" alt=\"\" class=\"wp-image-336\" srcset=\"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2023\/05\/\u7406\u79d1\u697c6\u53f7\u697c111.png 2268w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2023\/05\/\u7406\u79d1\u697c6\u53f7\u697c111-200x300.png 200w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2023\/05\/\u7406\u79d1\u697c6\u53f7\u697c111-683x1024.png 683w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2023\/05\/\u7406\u79d1\u697c6\u53f7\u697c111-768x1152.png 768w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2023\/05\/\u7406\u79d1\u697c6\u53f7\u697c111-1024x1536.png 1024w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2023\/05\/\u7406\u79d1\u697c6\u53f7\u697c111-1365x2048.png 1365w, https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-content\/uploads\/sites\/6\/2023\/05\/\u7406\u79d1\u697c6\u53f7\u697c111-624x936.png 624w\" sizes=\"auto, (max-width: 2268px) 100vw, 2268px\" \/><\/figure>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Higgs physics in ATLAS experiment Higgs boson discovery [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-456","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-json\/wp\/v2\/pages\/456","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-json\/wp\/v2\/comments?post=456"}],"version-history":[{"count":2,"href":"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-json\/wp\/v2\/pages\/456\/revisions"}],"predecessor-version":[{"id":458,"href":"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-json\/wp\/v2\/pages\/456\/revisions\/458"}],"wp:attachment":[{"href":"https:\/\/web.tdli.sjtu.edu.cn\/kunliu\/wp-json\/wp\/v2\/media?parent=456"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}