COMPASS Experiment

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html style="height: 100%"> <head> <title>COMPASS Experiment</title>   <link rel="shortcut icon" href="icons/compass_favicon_new.ico"> <meta http-equiv="content-type" content="text/html; charset=utf-8"> <meta content="Compass experiment at CERN" name="description"> <meta http-equiv="Content-Language" content="en-us"> <meta content="Compass, CERN, gluon polarization, deep-inelastic scattering, muon beam, hadron beam, nucleon, quarks" name="keywords"> <!base href="https://wwwcompass.cern.ch/" target="_blank" > <style> a:link {color: #008000; text-decoration: none;} a:visited {color: #008000; text-decoration: none;} a:hover {color: #008000; text-decoration: underline;} a:active {color: #008000; text-decoration: none;} .colHeader {background-color: #0000ff; color: #ffffff; font-size: 14pt; font-weight: bold; padding: 0pt 5pt; white-space:nowrap; font-family: times;} .leftTab {width: 18%; 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border: 0px; width: 90%"> <tbody> <tr>   <td width="118"><img src="Pictures/COMPASS_anniversary_logo.png" border="0" height="125" width="125"></td> <td align="center"><font color="#0000ff" face="Arial Black"><span style="font-size: 42pt;">COMPASS</span></font><br> <font color="#0000ff" face="Arial" size="4">COmmon Muon Proton Apparatus for Structure and Spectroscopy</font></td> <td width="220"> <table width="220"> <tbody> <tr>  <td width=120 valign="top"><a href="http://www.cerncourier.com"><img src="Pictures/CERNcourier/CERN_courier_logo.png" border="0" width="100"></a><br> <font size="2"> <a href="https://cds.cern.ch/static/pdfjs/web/viewer.html?FILE=/record/2019818/files/CERN%20Courier%20June%202015.pdf#page=5">Issue 2015/55-05</a><br> <font size="2"> <a href="https://cds.cern.ch/static/pdfjs/web/viewer.html?FILE=/record/1993759/files/CERN%20Courier%20March%202015.pdf#page=3">Issue 2015/55-02</a><br> <font size="2"> <a href="https://cds.cern.ch/static/pdfjs/web/viewer.html?FILE=/record/1734558/files/vol50-issue7.pdf#page=34">Issue 2010/50-7</a><br> <font size="2"> <a href="https://cds.cern.ch/static/pdfjs/web/viewer.html?FILE=/record/1733950/files/vol46-issue6.pdf#page=15">Issue 2006/46-6</a><br> <a href="https://cds.cern.ch/static/pdfjs/web/viewer.html?FILE=/record/1733922/files/vol46-issue4.pdf#page=16">Issue 2006/46-4</a><br> <a href="https://cds.cern.ch/static/pdfjs/web/viewer.html?FILE=/record/1732985/files/vol39-issue7.pdf#page=22">Issue 1999/39-7</a><br> <a href="http://cdsweb.cern.ch/journal/"> <img src="icons/bulletin.gif" border="0"></a><br> <a href="compass/public_relations/bulletin/060130_bulletin.html">2006/06</a> | <a href="compass/public_relations/bulletin/060130_bulletin.pdf">scan</a> <br> <a href="compass/public_relations/bulletin/020603_bulletin.html">2002/23</a> </font></font></td> <td valign="top"><a href="https://cds.cern.ch/static/pdfjs/web/viewer.html?FILE=/record/2910671/files/CERNCourier2024SepOct-digitaledition.pdf#page=1"> <img src="https://cerncourier.com/wp-content/uploads/2024/09/CCSepOct24_pOFCL.jpg" border="0" height="150"></a></td> </tr> </tbody> </table> </td> </tr> </table> </div> <!************************ news ***********************************************************************************************> <!div style="width: 70%; margin-left: 305px; font-size: 12pt; font-family: arial; text-align: left"> <div style="width: 51.8%; margin-left: auto; margin-right: auto; font-size: 12pt; font-family: arial; text-align: left"> <table style="border-collapse: collapse"> <tr><td width=50px> <img src="icons/new.gif" style="visibility: visible; vertical-align: middle;"> <td> <a href="https://indico.cern.ch/e/IWHSS-CPHI-2024"> IWHSS-CPHI-2024 workshop, Yerevan </a> </td></tr> <tr><td width=50px>  <td> <a href="https://indico.cern.ch/e/IWHSS-2022"> IWHSS-2022 workshop (COMPASS anniversary edition), CERN </a> </td></tr> <tr><td width=50px>  <td> <a href="https://cerncourier.com/a/compass-points-to-triangle-singularity/"> COMPASS points to triangle singularity (CERN Courier) </a> </td></tr> <tr><td width=50px>  <td> <a href="https://www.uni-bonn.de/en/news/200-2021"> Transformation in the particle zoo ("Triangle singularity" press-release, University of Bonn)  </a> </td></tr> <tr><td width=50px> <td> <a href="https://ep-news.web.cern.ch/compass-amber-exploring-fundamental-properties-hadrons"> From COMPASS to AMBER: exploring fundamental properties of hadrons</a> </td></tr> <tr><td> <td> <a href="compass/public_relations/WhyPionPol.pdf">Goldstone nature of the pion confirmed</a> (<a href="compass/public_relations/press_polarisability.html">Press</a>) </td></tr> <tr><td> <td> <a href="https://www.sciencenews.org/blog/science-ticker/new-particle-may-be-made-four-quarks">Science Ticker: a<sub>1</sub>(1420)</a> <a href="compass/public_relations/150202_science_ticker_a1_1420.pdf">(pdf)</a> </td></tr> <tr><td> <td> <a href="http://www.weltderphysik.de/thema/bmbf/physik-der-kleinsten-teilchen/compass/">Welt der Physik</a> </td></tr> <tr><td width=50px> <img src="Pictures/Ukraine.png" style="visibility: visible; vertical-align: middle;"> <td> The COMPASS Collaboration firmly condemns the War in Ukraine and strongly supports <br><a href="https://home.cern/solidarity-ukraine"> the CERN Council statement </a> </td></tr> </table> </div> <br><br> <div style="position: relative; width: 90%; margin-left: auto; margin-right: auto"> <div style="position: absolute; left: 0px"> <a href="https://greybook.cern.ch/greybook/experiment/detail?id=NA58">SPS experiment NA58</a> </div> <div style="position: absolute; right: 0px; width: 200px;"> <a href="compass/organisation/safety">Safety</a> </div> </div> <br><br><br><br> <!************************ table section 1 ******************************> <table style="margin-left: auto; margin-right: auto; border-collapse: collapse; color: #008000; width: 90%; align: center; font-family: arial"> <tbody> <!************************ left side ******************************> <tr> <td class="leftTab"> <div class="colHeader"> ORGANIZATION </div> <ul class="colList"> <li> <a href="compass/organisation/whoiswho.html">Who is who</a> and <a href="compass/organisation/responsibilities.html">Responsibilities</a> <li> <a href="compass/organisation/contacts.html">Contact Information</a> <li> <a href="compass/organisation/institutes.html">Institutes</a> <li> <a href="compass/organisation/members">Members</a> (<a href="compass/organisation/members_phaseI">COMPASS I</a>) <li> <a href="compass/gl">Collaboration Board</a> <li> <a href="compass/tech-board/">Technical Board</a>    <li> <a href="compass/publications/">Publication Committee</a> <li> Election <a href="compass/election/election2021.pdf">2021</a> <a href="compass/election/election2019.pdf">2019</a> <a href="compass/election/election2017.pdf">2017</a> <a href="compass/election/election2015.pdf">2015</a> <a href="compass/election/election2013.html">2013-2001</a> <li> <a href="compass/organisation/visits">Visits</a> <li> <a href="https://cern.service-now.com/service-portal?id=privacy_policy&se=compass-na58&notice=website">Privacy Notice</a> <li>   <li> <a href="https://nqf-m2.web.cern.ch/">AMBER collaboration webpage</a>  </ul> <div class="colHeader"> EXPERIMENT </div> <ul class="colList"> <li> <a href="compass/detector/">COMPASS Set-up</a> <li> <a href="compass/detector/calorimetry/welcome.html">Hadron Calorimeters</a> <li> <a href="compass/detector/calorimetry/welcome.html">EM Calorimeters</a> <li> <a href="compass/detector/gem/welcome.html">GEM detectors</a> <li> <a href="http://cbernet.home.cern.ch/cbernet/Micromegas/">Micromegas</a> <li> <a href="compass/detector/trigger/welcome.html">Trigger</a> <li> <a href="compass/detector/rich/welcome.html">RICH</a> <li> <a href="compass/detector/rich/rich_locked/RICH_up-grade/">RICH Upgrade</a> <li> <a href="compass/detector/w45/welcome.html">W45</a> <li> <a href="compass/tech-board/sm1/sm1.html">SM1 Magnet</a> <li> <a href="compass/detector/target/welcome.html">Polarized Target</a> <li> <a href="http://www.staff.uni-mainz.de/jasinsk">Cedars</a> <li> <a href="compass/gallery/welcome.html">COMPASS Gallery</a> <li>   <li>   </ul> <div class="colHeader"> PHYSICS </div> <ul class="colList"> <li> <a href="http://compassweb.ts.infn.it/transversity/">Transversity</a> <li> <a href="compass/gpd/index.html">GPDs</a> <li> <a href="compass/future_physics/drellyan">Drell-Yan</a> <li> <a href="compass/hadron-analysis/index.html">Hadron analysis</a> <li>   </ul> <div class="colHeader"> USEFUL LINKS </div> <ul class="colList"> <li> <a href="http://mmmservices.web.cern.ch/mmmservices/">My Mail and More</a> <li> <a href="https://directory.web.cern.ch/">CERN</a> <li> <a href="compass/outside.html#hep">High Energy Physics</a> <li> <a href="compass/outside.html#www">WWW</a> <li>   <li>    <a href="http://user.web.cern.ch/User/Welcome.html"><img src="icons/CERN_logo.png" border="0" height="50"</a> </ul> <!************************ center *********************************> <td class="centTab"> <div class="plot"> <a href="Pictures/COMPASS_setup_2022.png"> <img src="Pictures/COMPASS_setup_2022.png" align="center" border="0pt" width="100%"></a> <br><br> <iframe src="https://wwwcompass.cern.ch/compass/panorama/" width="100%" height="400px" frameBorder="0" style="background-color: #ccffff"></iframe> <br><br> A sketch of the 60 m long COMPASS two-stage spectrometer. A 360° photo of the COMPASS setup<a href="https://photos.google.com/share/AF1QipMCjdi6ZCsqL8tMAQnSqUiK8eiO7IIne_Z9W1WOYKqqvEOImeVFowChV6iBuQqGIA/photo/AF1QipN-ER7hMlHaYQtUIMLvV86KV24ByJiHGoG0xb54?key=VlpOZnlTTGc5clhia2NPcTNWVEJkdHIxamdvemFn" target="_blank" rel="noopener noreferrer"> <img src="Pictures/360deg.png" border="0" height="16"></a>  </div> <br> <div class="center">     COMPASS is a high-energy physics experiment at the Super Proton Synchrotron (SPS) at <a href="http://user.web.cern.ch/user">CERN</a> in Geneva, Switzerland. The purpose of this experiment is the study of hadron structure and hadron spectroscopy with high intensity muon and hadron beams. <br>     On February 1997 the experiment was approved by CERN and the final Memorandum of Understanding was signed in September 1998. The spectrometer was installed in 1999–2000 and commissioned during a technical run in 2001. The physics experiments started in summer 2002 with a muon beam and polarised proton and deuteron targets. These semi-inclusive deep inelastic scattering (SIDIS) experiments reveal details of the quark-gluon structure of the nucleon, in particular the gluon polarisation and transverse-momentum-dependent correlations. After the shutdown in 2005, COMPASS resumed the SIDIS experiments in 2006 and 2007 with a new large-aperture target magnet. The spin structure measurements were continued in 2010 and 2011. <br>     The years 2008 and 2009 were dedicated to the hadron spectroscopy programme with pion and proton beams scattering off a liquid hydrogen target and nuclear targets. An unprecedented amount of data was collected and has allowed for a much refined analysis of the final states, and is still revealing subtle details of the light-meson spectrum. Part of 2009 was dedicated to the study of the pion polarisability using Primakoff scattering of pions from heavy nuclei. This measurement had been prepared by a pilot run in 2004. The programme was continued in 2012 under COMPASS phase-II. <br>     Phase-II of COMPASS is primarily dedicated to the transverse and 3D structure of nucleons using Deeply Virtual Compton scattering (DVCS), Hard Exclusive Meson Production (HEMP), SIDIS and polarised Drell-Yan (DY) reactions. Approved in 2010, it started in 2012 with a Primakoff run and a DVCS pilot run using a muon beam and a long liquid hydrogen target with a huge recoil detector. The first-ever polarised Drell-Yan measurement with a beam of negative pions and a polarised proton target was successfully performed in 2015 and the data taking was resumed in 2018. The years 2016 and 2017 were dedicated to DVCS measurement and simultaneously data on HEMP and SIDIS were collected. In 2021-2022 after long shut-down 2, further measurements of SIDIS off transversely polarised deuterons were performed. <br><br> About 200 physicists from 13 countries and 25 institutions work in COMPASS.  </div></td> <!************************ right side *****************************> <td class="righTab"> <div class="colHeader"> DATA TAKING </div> <ul class="colList">  <li> <a href="compass/run/run2022/index.php"><font color="#FF0000">Muon run 2022</font></a> <a href="https://compassshifts.web.cern.ch/compassshifts/index.php"></a>  <li> <a href="compass/run/run2021/">Muon run 2021</a>, <a href="compass/run/run2011/">2011</a>, <a href="compass/run/run2010/">2010</a>, <a href="compass/run/run2007/">2007</a>, <a href="compass/run/run2006/">2006</a>, <a href="compass/run/run2004/">2004</a> <li> <a href="compass/run/run2020/welcome.html">Dry-Run 2020</a> <li> <a href="compass/run/run2018/">Drell-Yan run 2018</a>, <a href="compass/run/run2015/">2015</a>, <a href="compass/run/run2014/">2014</a> <li> <a href="compass/run/run2017/">GPD run 2017</a>, <a href="compass/run/run2016/">2016</a> <li> <a href="compass/run/run2012/">Hadron run 2012</a>, <a href="compass/run/run2009/">2009</a>, <a href="compass/run/run2008/">2008</a>, <a href="compass/run/hadron_run/">old</a> <li> <li> <a href="http://sba.web.cern.ch/sba/BeamsAndAreas/M2/M2_presentation.html">The M2 beam line</a>  <li> <a href="/logbook/">Electronic logbook</a> (<a href="/runLogbook/dirphp/">old logbook</a>) <li> <a href="/event_display/">Online event display</a>, <a href="http://ges.home.cern.ch/ges/phast/onl_ev_dis/">PHAST event display</a> <li> <a href="https://wwwcompass.cern.ch/experiment_overview/">Online status info</a>, <a href="https://wwwcompass.cern.ch/proxy/">COMPASS proxy</a> <li> <a href="compass/detector/daq/">DAQ</a>, <a href="http://compass-dcs.web.cern.ch/compass-dcs/scripts/welcome.asp">DCS</a>, <a href="spill/spill.html">Beam Monitoring</a> <li> <a href="https://twiki.cern.ch/twiki/bin/view/Compass/WebHome">COMPASS Wiki</a>, <a href="https://gitlab.cern.ch/compass">GitLab </a>   </ul> <div class="colHeader"> DATA ANALYSIS </div> <ul class="colList"> <li> <a href="compass/software/analysis/transparencies/">Analysis Meetings</a> <li> <a href="compass/software/offline/welcome.html#software">Software</a> <li> <a href="compass/software/analysis/seminars/welcome.html">Seminars</a> <li> <a href="elog">ELOG logbooks</a> </ul> <br> <div class="colHeader"> PUBLICATIONS </div> <ul class="colList"> <li> <a href="compass/publications/">Publications-all page</a> <li> <a href="compass/publications/welcome.html#proposal">Proposals</a> <li> <a href="compass/publications/papers/">Papers</a> <li> <a href="compass/publications/welcome.html#target">Target Papers</a> <li> <a href="compass/publications/welcome.html#theses">Theses</a> <li> <a href="compass/publications/talks/">Talks</a>  <li> <a href="compass/notes/">COMPASS Notes</a> <li> <a href="compass/results/">Released results</a> </ul> <div class="colHeader"> MEETINGS </div> <ul class="colList"> <li> <a href="compass/compass-meetings.html">Collaboration Meetings</a> <li> <a href="compass/weekly/2020/welcome.html">Weekly meetings</a> <li> <a href="compass/tech-board/">TB meetings</a> <li> <a href="compass/FE-meetings/">FE meetings</a> <li> <a href="http://indico.cern.ch/category/6814/calendar">Meetings database</a>, <a href="https://docs.google.com/spreadsheets/d/1deumtNp4toyiLfShhsUOJJ8dIiNQfFKCzX5ACoVleMw/edit?usp=sharing"><font color="#FF0000">2024 Calendar</font></a> </ul> <div class="colHeader"> CERN PAGES </div> <ul class="colList"> <li> <a href="https://maps.cern.ch/mapsearch/">CERN Map/Buildings</a> <li> <a href="http://greybook.cern.ch/">Experiments at CERN</a> <li> <a href="https://edh.cern.ch/edhcat/Browser">CERN Stores</a> <li> <a href="http://cdsweb.cern.ch/">Document Server</a> <li> <a href="https://edh.cern.ch">EDH</a> </ul> </td> </tr> <!*****************************************************> </table> <address> <center> This page was last updated on <script type="text/javascript"> update = new Date(document.lastModified); theMonth = update.getMonth() + 1; theDay = update.getDate(); theYear = update.getFullYear(); document.write(theDay + "/" + theMonth + "/" + theYear); </script> </center> </address> <br> </body> </html>

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COMPASS Experiment