The ATLAS experiment https://timeline.web.cern.ch/taxonomy/term/143 en ATLAS observes elusive Higgs boson decay to a pair of bottom quarks https://timeline.web.cern.ch/atlas-observes-elusive-higgs-boson-decay-pair-bottom-quarks <div data-history-node-id="753" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">28 08, 2018</div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>The Higgs boson is <a href="http://atlas.cern/updates/press-statement/observation-higgs-boson-decay-pair-bottom-quarks">observed decaying into a pair of bottom quarks</a> for the first time. This elusive interaction is predicted to make up almost 60% of the Higgs boson decays and is thus primarily responsible for the Higgs natural width.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">CDS Media</div> </div> </div> Fri, 02 Nov 2018 10:30:26 +0000 abha 753 at https://timeline.web.cern.ch ATLAS observes direct interaction of Higgs boson with top quark https://timeline.web.cern.ch/atlas-observes-direct-interaction-higgs-boson-top-quark <div data-history-node-id="752" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">04 06, 2018</div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>ATLAS announces the <a href="http://atlas.cern/updates/press-statement/atlas-observes-tth-production">observation of Higgs bosons produced together with a top-quark pair</a>. This rare process is one of the most sensitive tests of the Higgs mechanism and its observation marked a significant milestone for the field of High-Energy Physics.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">CDS Media</div> </div> </div> Fri, 02 Nov 2018 10:28:35 +0000 abha 752 at https://timeline.web.cern.ch First direct evidence of light-by-light scattering at high energy https://timeline.web.cern.ch/first-direct-evidence-light-light-scattering-high-energy <div data-history-node-id="751" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">14 08, 2017</div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>ATLAS publishes the <a href="http://atlas.cern/updates/press-statement/atlas-sees-first-direct-evidence-light-light-scattering-high-energy">first direct evidence of high energy light-by-light scattering</a>, a very rare process in which two photons – particles of light – interact and change direction. The result, published in Nature Physics, confirms one of the oldest predictions of quantum electrodynamics.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">CDS Media</div> </div> </div> Fri, 02 Nov 2018 10:26:45 +0000 abha 751 at https://timeline.web.cern.ch Sighting the Higgs in its favourite decay https://timeline.web.cern.ch/sighting-higgs-its-favourite-decay <div data-history-node-id="750" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">06 06, 2017</div> <div class="field field--name-field-image field--type-image field--label-hidden field--item"> <img src="/sites/timeline.web.cern.ch/files/vhbb_0.png" width="494" height="480" alt="" typeof="foaf:Image" class="img-responsive" /> </div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>ATLAS sees the <a href="https://atlas-public.web.cern.ch/updates/physics-briefing/first-lhc-sighting-higgs-boson-its-favourite-decay">first LHC evidence of the Higgs boson decaying to a pair of b-quarks</a>. Despite being the dominant Higgs decay, finding evidence in this channel was a major challenge. Following years of dedicated search, ATLAS was able to spot this elusive decay in 2017, with an observed significance of 3.6 σ (expectation 4.0 σ) when combining the Run 1 and Run 2 datasets.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">Image</div> </div> </div> Fri, 02 Nov 2018 10:24:41 +0000 abha 750 at https://timeline.web.cern.ch First Technical Design Report released for ATLAS upgrade https://timeline.web.cern.ch/first-technical-design-report-released-atlas-upgrade <div data-history-node-id="749" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">01 04, 2017</div> <div class="field field--name-field-image field--type-image field--label-hidden field--item"> <img src="/sites/timeline.web.cern.ch/files/2017-upgradeTDR.jpg" width="341" height="480" alt="" typeof="foaf:Image" class="img-responsive" /> </div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>ATLAS begins preparations for the Phase II upgrade of the experiment, which will be in place for the <a href="http://hilumilhc.web.cern.ch">High-Luminosity LHC</a>. This upgraded ATLAS experiment will begin data taking in 2026.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">Image</div> </div> </div> Fri, 02 Nov 2018 10:20:34 +0000 abha 749 at https://timeline.web.cern.ch First measurement of the W boson mass at the LHC https://timeline.web.cern.ch/first-measurement-w-boson-mass-lhc <div data-history-node-id="748" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">13 12, 2016</div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>ATLAS shows its strength for precision physics, taking a <a href="https://atlas.cern/updates/physics-briefing/measuring-w-boson-mass">world-class measurement of the W boson mass</a>. Precise measurements of the W boson mass are vital, as the parameter is related in the Standard Model to the masses of the top quark and the Higgs boson. Measuring the W mass can thus test the self-consistency of the Standard Model, since any deviation from the predicted relation would be a sign of new physics. This first ATLAS result is consistent and as precise as the best previous measurement of the W mass.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">CDS Media</div> </div> </div> Fri, 02 Nov 2018 10:15:03 +0000 abha 748 at https://timeline.web.cern.ch Combination of Higgs boson production and decay measurements of ATLAS and CMS https://timeline.web.cern.ch/combination-higgs-boson-production-and-decay-measurements-atlas-and-cms <div data-history-node-id="747" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">07 06, 2016</div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>The ATLAS and CMS Experiments release <a href="https://arxiv.org/abs/1606.02266">combined measurements</a> of the Higgs boson production and decay rates. Examining all data from the LHC Run-1, the result gives a snapshot of the world’s knowledge of the mysterious Higgs boson. In addition to setting constraints on Higgs couplings to vector bosons and fermions, the combination established the observation of Higgs to di-tau decay and weak-boson-fusion production.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">CDS Media</div> </div> </div> Fri, 02 Nov 2018 10:12:33 +0000 abha 747 at https://timeline.web.cern.ch ATLAS Begins Recording Physics Data at 13 TeV https://timeline.web.cern.ch/atlas-begins-recording-physics-data-13-tev <div data-history-node-id="746" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">03 06, 2015</div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>ATLAS began recording physics data from 13 TeV proton collisions, which allow for precision studies of the Higgs boson and other Standard Model particles, as well as the search for new particles with higher masses.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">CDS Media</div> </div> </div> Fri, 02 Nov 2018 10:10:49 +0000 abha 746 at https://timeline.web.cern.ch ATLAS finds evidence for the rare electroweak W±W± production https://timeline.web.cern.ch/atlas-finds-evidence-rare-electroweak-w-w-production <div data-history-node-id="745" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">23 05, 2014</div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>ATLAS publishes <a href="https://atlas-public.web.cern.ch/updates/physics-briefing/atlas-finds-evidence-rare-electroweak-w-w-production">first evidence</a> for electroweak production of W bosons with the same charge. This channel receives contributions from quartic interactions between W bosons. This rare process gives physicists a new way to study electroweak symmetry breaking and to indirectly probe the properties of the Higgs boson.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">CDS Media</div> </div> </div> Fri, 02 Nov 2018 10:08:32 +0000 abha 745 at https://timeline.web.cern.ch Nobel Prize for the Higgs discovery https://timeline.web.cern.ch/nobel-prize-higgs-discovery <div data-history-node-id="744" class="node node--type-timeline-entry node--view-mode-rss ds-1col clearfix"> <div class="field field--name-field-date-historical-2 field--type-datetime field--label-hidden field--item">10 08, 2013</div> <div class="field field--name-body field--type-text-with-summary field--label-hidden field--item"><p>The 2013 Nobel Prize in physics is awarded to Professors François Englert and Peter Higgs "for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles, and which recently was confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN’s Large Hadron Collider". ATLAS and CMS physicists cheered the announcement.</p></div> <div class="field field--name-field-timeline field--type-entity-reference field--label-inline"> <div class="field--label">Timeline</div> <div class="field--items"> <div class="field--item"><a href="/taxonomy/term/143" hreflang="en">The ATLAS experiment</a></div> </div> </div> <div class="field field--name-field-media-type field--type-list-string field--label-above"> <div class="field--label">Media type</div> <div class="field--item">CDS Media</div> </div> </div> Fri, 02 Nov 2018 10:02:38 +0000 abha 744 at https://timeline.web.cern.ch