{"id":532,"date":"2026-01-13T11:20:06","date_gmt":"2026-01-13T10:20:06","guid":{"rendered":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/?p=532"},"modified":"2026-01-13T11:20:06","modified_gmt":"2026-01-13T10:20:06","slug":"cobiplane-the-discovery-of-five-new-spider-pulsars","status":"publish","type":"post","link":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/cobiplane-the-discovery-of-five-new-spider-pulsars\/","title":{"rendered":"COBIPLANE: The discovery of five new spider pulsars"},"content":{"rendered":"<div class=\"wpb-content-wrapper\"><p>[vc_row][vc_column width=&#8221;2\/3&#8243;][vc_column_text css=&#8221;&#8221;]Compact binary millisecond pulsars, also known as &#8220;spiders&#8221;, host the most massive neutron stars ever\u00a0observed\u00a0to date. Expanding the currently known spider population holds the key to\u00a0determining\u00a0the\u00a0maximum\u00a0neutron star mass, which has crucial implications for astrophysics, nuclear\u00a0physics\u00a0and gravitational wave\u00a0astronomy.\u00a0Searching for the variable optical emission of their companions can reveal a\u00a0radio-obscured\u00a0population of spiders.\u00a0In\u00a0the linked\u00a0article, we present the\u00a0results of\u00a0our\u00a0<strong>CO<\/strong>mpact\u00a0<strong>BI<\/strong>nary\u00a0<strong>P<\/strong>ulsar search in the low-<strong>LA<\/strong>titude\u00a0<strong>NE<\/strong>ighborhood\u00a0(COBIPLANE), which\u00a0led to\u00a0discovery\u00a0of\u00a0five\u00a0variable optical\u00a0sources\u00a0identified\u00a0as new spider candidates. Their optical light curves show flux modulation in the sub-day period range and effective temperatures of 5000\u22126000 K, consistently\u00a0with\u00a0spider\u00a0pulsars.\u00a0COBIPLANE\u00a0selection criteria, improved compared to\u00a0its\u00a0predecessor survey COBIPULSE, allowed us to find two candidates close to the Galactic plane:\u00a04FGL J1517.9\u22125233\u00a0at b=4.18\u00b0\u00a0and 4FGL J1639.3\u22125146\u00a0at b=\u22123.32\u00b0.\u00a0These\u00a0findings\u00a0will not only facilitate future radio observations of these\u00a0five\u00a0candidates, but\u00a0will also allow us to measure their neutron star masses via optical light curve modelling.[\/vc_column_text][\/vc_column][vc_column width=&#8221;1\/3&#8243;][vc_empty_space]<style type=\"text\/css\" data-type=\"the7_shortcodes-inline-css\">.icon-with-text-shortcode.icon-text-id-fa586e41ff321532182674b1df5b67c1 .text-icon {\n  width: 60px;\n  height: 60px;\n  line-height: 60px;\n  font-size: 32px;\n  border-radius: 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class=\"icon-inner\"><i class=\"dt-regular-icon soc-icon icomoon-the7-font-the7-login-02\"><\/i><i class=\"dt-hover-icon soc-icon icomoon-the7-font-the7-login-02\"><\/i><\/span><\/span><h4 class=\"dt-text-title\"  >Marco Turchetta<\/h4><\/div>[vc_empty_space][vc_btn title=&#8221;View article&#8221; color=&#8221;primary&#8221; align=&#8221;center&#8221; i_icon_fontawesome=&#8221;fa fa-regular fa-newspaper&#8221; css=&#8221;&#8221; add_icon=&#8221;true&#8221; link=&#8221;url:https%3A%2F%2Farxiv.org%2Fabs%2F2512.23815|target:_blank&#8221;][\/vc_column][\/vc_row]<\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>[vc_row][vc_column width=&#8221;2\/3&#8243;][vc_column_text css=&#8221;&#8221;]Compact binary millisecond pulsars, also known as &#8220;spiders&#8221;, host the most massive neutron stars ever\u00a0observed\u00a0to date. Expanding the currently known spider population holds the key to\u00a0determining\u00a0the\u00a0maximum\u00a0neutron star mass, which has crucial implications for astrophysics, nuclear\u00a0physics\u00a0and gravitational wave\u00a0astronomy.\u00a0Searching for the variable optical emission of their companions can reveal a\u00a0radio-obscured\u00a0population of spiders.\u00a0In\u00a0the linked\u00a0article, we present&hellip;<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[24,8],"tags":[],"class_list":["post-532","post","type-post","status-publish","format-standard","hentry","category-article","category-news","category-24","category-8","description-off"],"_links":{"self":[{"href":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/wp-json\/wp\/v2\/posts\/532","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/wp-json\/wp\/v2\/comments?post=532"}],"version-history":[{"count":0,"href":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/wp-json\/wp\/v2\/posts\/532\/revisions"}],"wp:attachment":[{"href":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/wp-json\/wp\/v2\/media?parent=532"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/wp-json\/wp\/v2\/categories?post=532"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/home.phys.ntnu.no\/LOVE-NEST\/wp-json\/wp\/v2\/tags?post=532"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}