{"id":1992,"date":"2009-05-20T08:37:11","date_gmt":"2009-05-20T13:37:11","guid":{"rendered":"http:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=1992"},"modified":"2009-05-20T09:58:25","modified_gmt":"2009-05-20T14:58:25","slug":"why-colliders-have-two-detectors","status":"publish","type":"post","link":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=1992","title":{"rendered":"Why Colliders Have Two Detectors"},"content":{"rendered":"<p>Last year the D0 collaboration at the Tevatron <a href=\"http:\/\/arxiv.org\/abs\/0808.4142\">published<\/a> a claim of first observation of an &Omega;<sub>b<\/sub> particle (a baryon containing one bottom and two strange quarks), with a significance of 5.4 sigma and a mass of 6165 +\/- 16.4 MeV.  This mass was somewhat higher than expected from lattice gauge theory calculations.<\/p>\n<p>Yesterday the CDF collaboration <a href=\"http:\/\/arxiv.org\/abs\/0905.3123\">published<\/a> a claim of observation of the same particle, with a significance of 5.5 sigma and a mass of 6054.4 +\/- 6.9 MeV.<\/p>\n<p>So, both agree that the particle is there at better than 5 sigma significance, but D0 says (at better than 6 sigma) that CDF has the mass wrong, and CDF says (at lots and lots of sigma..) that D0 has the mass wrong.   They can&#8217;t both be right&#8230;<\/p>\n<p>For a detailed discussion, see <a href=\"http:\/\/www.scientificblogging.com\/quantum_diaries_survivor\/nitpicking_omega_b_discovery\">here<\/a>, <a href=\"http:\/\/www.scientificblogging.com\/quantum_diaries_survivor\/nitpicking_omega_b_baryon_part_ii\">here<\/a> and <a href=\"http:\/\/www.scientificblogging.com\/quantum_diaries_survivor\/real_discovery_omega_b_released_cdf_today\">here<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Last year the D0 collaboration at the Tevatron published a claim of first observation of an &Omega;b particle (a baryon containing one bottom and two strange quarks), with a significance of 5.4 sigma and a mass of 6165 +\/- 16.4 &hellip; <a href=\"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=1992\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[9],"tags":[],"class_list":["post-1992","post","type-post","status-publish","format-standard","hentry","category-experimental-hep-news"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/1992","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1992"}],"version-history":[{"count":6,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/1992\/revisions"}],"predecessor-version":[{"id":1998,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/1992\/revisions\/1998"}],"wp:attachment":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1992"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1992"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1992"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}