{"id":698,"date":"2025-08-26T02:26:23","date_gmt":"2025-08-26T02:26:23","guid":{"rendered":"http:\/\/ds-web.lngs.infn.it\/?page_id=698"},"modified":"2025-11-19T00:16:16","modified_gmt":"2025-11-19T00:16:16","slug":"search-for-sub-gev-dark-matter","status":"publish","type":"page","link":"http:\/\/ds-web.lngs.infn.it\/index.php\/experiment\/search-for-sub-gev-dark-matter\/","title":{"rendered":"DarkSide-20k"},"content":{"rendered":"\t\t
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Author: Michela Lai<\/strong><\/em><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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After the success of the DarkSide-50 experiment, the natural first step for the Global Argon Dark Matter Collaboration\u2014bringing together the joint efforts of DarkSide-50, miniCLEAN, ArDM and DEAP-3600\u2014is to scale up from a 50 kg liquid argon target to a multi-tonne one, while maintaining an ultra-low background level from the radioactivity of detector materials.<\/span><\/p>\n

DarkSide-20k (DS20k)<\/b>, currently under construction at the Laboratori Nazionali del Gran Sasso (LNGS), envisions a 50-tonne volume of ultra-pure underground argon, extracted from the URANIA plant, housed in a dual-phase Time Projection Chamber (TPC) similar to that of DarkSide-50. This TPC is submerged in a 32-tonne underground single-phase liquid argon chamber serving as the Inner Veto, which itself is enclosed within the Outer Veto\u2014comprising 650 tonnes of atmospheric single-phase liquid argon.<\/span><\/p>\n

The TPC is, of course, the very core of the experiment, where we aim to detect elusive WIMP dark matter candidates. The veto systems are designed to reject background events induced by standard particles, which produce scintillation light in at least one veto layer and the TPC\u2014unlike the expected signal from WIMPs.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Cross-section of the DarkSide-20k experiment, under construction at the Laboratori Nazionali del Gran Sasso (LNGS). In grey, at the very center, is shown the Inner Detector, consisting of the octagonal-shaped double-phase Time Projection Chamber (TPC,) and the Inner Veto, respectively featuring 50 tonnes and 32 tonnes of ultra radio-pure underground argon. In yellow the Outer Veto, with its 650 tonnes of liquid atmospheric argon.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Specifically, the Outer Veto is designed to reject events caused by the small number of muons that penetrate into the underground lab. The Inner Veto, on the other hand, leverages the neutron-capturing power of hydrogen in the acrylic that separates the TPC vessel from the Inner Veto bath. When neutrons interact with the acrylic, they emit gamma rays that shine in both the TPC and the IV, producing a unique coincidence signal that helps distinguish neutrons from WIMPs.<\/span><\/p>

Given that we expect only a few dozen WIMP-induced events per year in liquid argon (with the exact number depending on the WIMP mass and its likelihood to interact via elastic scattering), the full suppression and rejection of background events has driven every aspect of the experiment\u2019s design\u2014from material selection to the development of our Photodetection Units (PDUs), which populate all three nested chambers. This same principle continues to guide the detailed assembly of the detector.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Current view of the DarkSide-20k outer cryostat, with its unique red color stealing the scene in Hall C at LNGS.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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Thanks to these efforts, over a planned 10-year data-taking period beginning in early 2028, the experiment will be capable of excluding\u2014or potentially detecting for the first time\u2014any WIMP candidate with a dark matter\u2013nucleon cross-section as low as <\/span>5 \u00d7 10\u207b\u2074\u2078 cm\u00b2<\/b>, for candidates as heavy as <\/span>1 TeV\/c\u00b2<\/b>.<\/span><\/p>

The next step will be <\/span>ARGO<\/b>, featuring a 400-tonne core detector\u2014marking the final milestone needed to definitively confirm or exclude the detectability of these elusive particles in direct detection experiments.<\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t

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Exclusion limits for WIMP dark matter candidates, along with several theoretical models (shown in yellow), are presented for DS20k and XENONnT, together with projections for the next-generation argon and xenon experiments, ARGO and XLZD, respectively.<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t
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In addition to the WIMP search, while construction progresses and PDUs are being characterized, we are also developing the analysis software and simulation tools\u2014both for post-processing at CNAF and for real-time data acquisition. Alongside dedicated performance monitoring, we are expanding the physics case by asking: <\/span>What are all the possible ways to exploit these 732 tonnes of argon?<\/span><\/i><\/p>

From neutrino physics to light dark matter candidates, we\u2019ve only just scratched the surface.<\/span><\/p>

Stay tuned!<\/strong><\/span><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t

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Some fun time at LNGS, at the very first stage of the experiment installation, to be placed on the deep blue. Stay tuned, and dive with us into the darkest universe! Check out the Contacts page for more information!<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"

Author: Michela Lai After the success of the DarkSide-50 experiment, the natural first step for the Global Argon Dark Matter Collaboration\u2014bringing together the joint efforts of DarkSide-50, miniCLEAN, ArDM and DEAP-3600\u2014is to scale up from a 50 kg liquid argon target to a multi-tonne one, while maintaining an ultra-low background level from the radioactivity of […]<\/p>\n","protected":false},"author":3,"featured_media":0,"parent":155,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"ocean_post_layout":"","ocean_both_sidebars_style":"","ocean_both_sidebars_content_width":0,"ocean_both_sidebars_sidebars_width":0,"ocean_sidebar":"0","ocean_second_sidebar":"0","ocean_disable_margins":"enable","ocean_add_body_class":"","ocean_shortcode_before_top_bar":"","ocean_shortcode_after_top_bar":"","ocean_shortcode_before_header":"","ocean_shortcode_after_header":"","ocean_has_shortcode":"","ocean_shortcode_after_title":"","ocean_shortcode_before_footer_widgets":"","ocean_shortcode_after_footer_widgets":"","ocean_shortcode_before_footer_bottom":"","ocean_shortcode_after_footer_bottom":"","ocean_display_top_bar":"default","ocean_display_header":"default","ocean_header_style":"","ocean_center_header_left_menu":"0","ocean_custom_header_template":"0","ocean_custom_logo":0,"ocean_custom_retina_logo":0,"ocean_custom_logo_max_width":0,"ocean_custom_logo_tablet_max_width":0,"ocean_custom_logo_mobile_max_width":0,"ocean_custom_logo_max_height":0,"ocean_custom_logo_tablet_max_height":0,"ocean_custom_logo_mobile_max_height":0,"ocean_header_custom_menu":"0","ocean_menu_typo_font_family":"0","ocean_menu_typo_font_subset":"","ocean_menu_typo_font_size":0,"ocean_menu_typo_font_size_tablet":0,"ocean_menu_typo_font_size_mobile":0,"ocean_menu_typo_font_size_unit":"px","ocean_menu_typo_font_weight":"","ocean_menu_typo_font_weight_tablet":"","ocean_menu_typo_font_weight_mobile":"","ocean_menu_typo_transform":"","ocean_menu_typo_transform_tablet":"","ocean_menu_typo_transform_mobile":"","ocean_menu_typo_line_height":0,"ocean_menu_typo_line_height_tablet":0,"ocean_menu_typo_line_height_mobile":0,"ocean_menu_typo_line_height_unit":"","ocean_menu_typo_spacing":0,"ocean_menu_typo_spacing_tablet":0,"ocean_menu_typo_spacing_mobile":0,"ocean_menu_typo_spacing_unit":"","ocean_menu_link_color":"","ocean_menu_link_color_hover":"","ocean_menu_link_color_active":"","ocean_menu_link_background":"","ocean_menu_link_hover_background":"","ocean_menu_link_active_background":"","ocean_menu_social_links_bg":"","ocean_menu_social_hover_links_bg":"","ocean_menu_social_links_color":"","ocean_menu_social_hover_links_color":"","ocean_disable_title":"default","ocean_disable_heading":"default","ocean_post_title":"","ocean_post_subheading":"","ocean_post_title_style":"","ocean_post_title_background_color":"","ocean_post_title_background":0,"ocean_post_title_bg_image_position":"","ocean_post_title_bg_image_attachment":"","ocean_post_title_bg_image_repeat":"","ocean_post_title_bg_image_size":"","ocean_post_title_height":0,"ocean_post_title_bg_overlay":0.5,"ocean_post_title_bg_overlay_color":"","ocean_disable_breadcrumbs":"default","ocean_breadcrumbs_color":"","ocean_breadcrumbs_separator_color":"","ocean_breadcrumbs_links_color":"","ocean_breadcrumbs_links_hover_color":"","ocean_display_footer_widgets":"default","ocean_display_footer_bottom":"default","ocean_custom_footer_template":"0","footnotes":""},"categories":[],"tags":[],"class_list":["post-698","page","type-page","status-publish","hentry","entry"],"_links":{"self":[{"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/pages\/698","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/comments?post=698"}],"version-history":[{"count":26,"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/pages\/698\/revisions"}],"predecessor-version":[{"id":903,"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/pages\/698\/revisions\/903"}],"up":[{"embeddable":true,"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/pages\/155"}],"wp:attachment":[{"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/media?parent=698"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/categories?post=698"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/ds-web.lngs.infn.it\/index.php\/wp-json\/wp\/v2\/tags?post=698"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}