{"id":185,"date":"2005-04-25T23:13:14","date_gmt":"2005-04-26T03:13:14","guid":{"rendered":"http:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=185"},"modified":"2005-04-25T23:13:14","modified_gmt":"2005-04-26T03:13:14","slug":"lhc-startup-scenarios","status":"publish","type":"post","link":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=185","title":{"rendered":"LHC Startup Scenarios"},"content":{"rendered":"<p>Everyone in the particle physics community is avidly awaiting the startup of the LHC accelerator at CERN, scheduled for 2007.  A new preprint by Gianotti and Mangano entitled <A href=\"http:\/\/www.arxiv.org\/abs\/hep-ph\/0504221\">LHC physics: the first one&#8211;two year(s)<\/A> gives some idea of what to expect. <\/p>\n<p>The design luminosity for the LHC is about 10<sup>34<\/sup>cm<sup>-2<\/sup>s<sup>-1<\/sup>, which is about 100 times the current luminosity of the Tevatron.  Current plans are to first cool down the machine in spring 2007, followed by commissioning single beams over the next few months, with first colliding beams in the second half of 2007.  During 2007, most effort will be devoted to commissioning the machine, followed by a shutdown for a few months.  A seven-month long physics run at luminosities of up to 2 x 10<sup>33<\/sup>cm<sup>-2<\/sup>s<sup>-1<\/sup> will take place during 2008.  This is 20 times the current Tevatron luminosity and the Tevatron seems to be averaging a total of about 15 pb<sup>-1<\/sup> per week, so one could expect a total luminosity of up to about 10 fb<sup>-1<\/sup> to be collected during 2008.  This is probably much too optimistic.  Experience with the Tevatron when it was turned on at the beginning of its latest run was that for quite a while it was running at only a tenth of the hoped for luminosity.  So perhaps 1 fb<sup>-1<\/sup> during 2008 is a more realistic expectation.<\/p>\n<p>According to Gianotti and Mangano, 1 fb<sup>-1<\/sup> will be enough to see squarks and gluinos at masses of up to about 1.5 Tev.  Seeing the Higgs is more demanding, especially if its mass is low.  If its mass if above 180 Gev, it should require 5-10 fb<sup>-1<\/sup>, if it is just above the LEP limit (114 Gev) it is likely to require more like 20 fb<sup>-1<\/sup>.<\/p>\n<p>Personally I think it&#8217;s quite unlikely the LHC will be seeing supersymmetric particles, so, of the things it is looking for, it will require good luck to get the data required to see the Higgs during 2008.  Even if this does happen, I&#8217;d guess that analyzing the data would take us into 2009.  If the LHC has trouble getting anywhere near design luminosity, things could take longer.  Of course everyone hopes that something completely unexpected will be found.  If this is dramatic enough, maybe there will be some exciting news in 2008.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Everyone in the particle physics community is avidly awaiting the startup of the LHC accelerator at CERN, scheduled for 2007. A new preprint by Gianotti and Mangano entitled LHC physics: the first one&#8211;two year(s) gives some idea of what to &hellip; <a href=\"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/?p=185\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"","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_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[1],"tags":[],"class_list":["post-185","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"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\/185","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=185"}],"version-history":[{"count":0,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/185\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=185"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=185"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.math.columbia.edu\/~woit\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=185"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}