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ATLAS to Present Updated Higgs Analysis Results in Upcoming Joint CERN / ICHEP Seminar
29 June 2012

The ATLAS Experiment will be presenting its most recent results from searches for the Higgs Boson at the LHC in a dedicated seminar to be held at CERN on 4 July at 9:00 CET.

The preliminary results, to be presented alongside those of CMS, are a significant update from earlier publications, as they will include the analysis of 8 TeV proton collision data recorded so far in 2012.

Previous measurements, based on 7 TeV proton collision data recorded in 2011, limited the mass of the Higgs at 95% confidence to a narrow range between about 115.5 GeV and 131 GeV, and a small excess of events above the expected background was seen by both ATLAS and CMS around 126 GeV.

The seminar will be held in the CERN Amphitheatre with a direct video link for physicists attending the ICHEP 2012 conference in Melbourne, Australia, and a public webcast on Registered journalists will be able to view the webcast in the CERN Council Chamber and a press conference will shortly follow.

The Higgs Boson is a key component of the Standard Model, a highly successful theory that provides a very precise description of matter. Identification of the Higgs Boson would be a major accomplishment, providing physicists with a better understanding of the mechanism that gives mass to elementary particles and opening the door to a variety of new physics searches.

ATLAS event containing four muons. This event is consistent with coming from two Z particles decaying: both Z particles decay to two muons each. Such events are produced by Standard Model processes without Higgs particles. They are also a possible signature for Higgs particle production, but many events must be analysed together in order to tell if there is a Higgs signal. This view is a zoom into the central part of the detector. The four muons are picked out as red tracks. Other tracks and deposits of energy in the calorimeters are shown in yellow.

Latest ATLAS Results to be Presented Down Under at ICHEP 2012
2 July 2012

Every other year, particle physicists gather together to share their latest results at the ICHEP (International Conference on High Energy Physics) conference. This year, more than 700 are attending the conference in Melbourne, Australia, July 4-11.

ATLAS will be sending the results of several dozen new analyses to ICHEP, covering the full scientific programme of the experiment, both precision measurements of Standard Model processes and searches for new physical phenomena - including the Higgs boson. A preview of the Higgs search results will be presented at a special joint video-linked seminar at CERN on the opening day of the conference.

ATLAS physics results to be presented are based upon the full 2011 data set and, in several cases, data from the first part of the 2012 run. The great performance of the LHC this year at 8 TeV collision energy has already allowed ATLAS to more than double the total data collected. The scope of results extends well beyond the Higgs. For instance, there are searches for new forces between particles; ATLAS is sensitive to particles with ranges only one twentieth of the range of the so-called "weak force", which itself has a range of only a tiny fraction of the radius of the proton.

Several searches for new “supersymmetric” particles will be reported; these hypothesized particles may be related to the mysterious dark matter that apparently makes up four fifths of the matter in the universe. Rounding out the searches are many new results on direct searches for signatures of “exotic” particles, for instance particles that could be candidates for the above mentioned dark matter or evidence for the existence of “extra dimensions” - spatial dimensions beyond the familiar three.

In addition, new precision studies of the Standard Model will be presented, including studies that probe either rare processes or the properties of the heavy quarks, bottom and top; these studies could provide indirect hints of new physics. In addition, ATLAS will be combining its measurements of the mass of the top quark - the heaviest elementary particle known - with similar measurements from CMS for an accuracy better than either experiment has reached on its own.

More than physicists are benefiting from the excitement of ICHEP; an unprecedented effort has been made this year to include the public and the media. Starting with a public webcast of the Higgs Seminar on the 4th, activities include an ATLAS exhibit at the Planetarium in Scienceworks, Masterclasses for high school students, teacher development day, a public panel discussion, and a public talk by ATLAS spokesperson Fabiola Gianotti.

Conference attendees will have the chance to take part in an Outreach & Education parallel session on Saturday morning. The session will feature presentations by scientific communication experts, including CERN’s Director General Rolf-Dieter Heuer and Australia’s famous radio personality Dr. Karl Kruszelnicki. An interactive session includes a panel discussion with Social Media experts and a Public Q&A session in the form of a Google Hangout.

More information and a schedule can be found on the conference web site and links to various events and venues are included below.

ATLAS Event Display Animations and Images
  Candidate four-muon event (2011) [animation]
  Candidate two-electron, two-muon event (2011) [animation]
  Candidate two-photon event (2011) [animation]
  Candidate four-muon event (2011) [image]
  Candidate two-electron, two-muon event (2011) [image]
  Candidate four-muon event (2011) [image]
  More ATLAS Event Images [web portal] [even more]
  More ATLAS Multimedia Material [web portal]

Background Material on the Higgs Boson
  The Origin of Mass [text]
  The Higgs Mechanism [animation]
  Explanation of Higgs Mass Limit Plot (Brazil Plot) [text, image]
  LHC Backgrounder on Higgs: General Information: [text]
  LHC Backgrounder on Higgs: Glossary of Terms: [text]
  LHC Backgrounder on Higgs: Evolution or Revolution? [text]
  Physics World Interview with Peter Higgs [text, audio]
  Explanation of Look-Elsewhere Effect by CMS [text]
  CERN Interview with ATLAS and CERN Experts [video]

ICHEP 2012 Information & Public Activities
  Conference Home Page [web portal]
  Schedule of Presentations [agenda]
  Twitter Stream [#ICHEP2012]
  Exhibit at Planetarium at Scienceworks (30 June – 15 July) [planetarium]
  High School Masterclasses at Australian Synchrotron (6 July) [synchrotron]
  Teacher Development Day at Melbourne Exhibition and Conference Centre (6 July) [venue]
  Honorary Degree for CERN Director General at University of Melbourne (6 July) [university]
  Panel Discussion at University of Melbourne (6 July) [event]
  Public Q&A Session via Google Hangout (7 July) [CERN Google+]
  Public Lecture by Fabiola Gianotti at University of Melbourne (10 July) [event]
  Press at the Pub (8 July) [venue TBA]
  Science at the Pub (10 July) [venue TBA]

Other Sources of Information from ATLAS
  ATLAS Home Page [web portal]
  ATLAS Live Webcast Streams [web portal]
  ATLAS on Social Media [Twitter] [Google +] [Facebook] [YouTube]
  ATLAS Blog [web portal]

Some Fun
  Jon Butterworth on Why Does the Higgs Decay? [Guardian Article]
  What would happen if you put your hand in the LHC? [60 Symbols Video]
  The ATLAS Boogie (How we really find the Higgs!) [YouTube Video]

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