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Sample records for cern lep collider

  1. The DELPHI detector at CERN's LEP collider

    CERN Multimedia

    1998-01-01

    DELPHI (DEtector with Lepton, Photon and Hadron Identification), is a detector for e+e- physics, with special emphasis on powerful particle identification , three-dimensional information, high granularity and precise vertex determination. It is installed at LEP (Large Electron and Positron collider) at CERN where it has operated since 1989.

  2. CERN Member States signatures at LEP inauguration

    CERN Multimedia

    1989-01-01

    The signatures of the dignitaries who represented CERN's Member States on the occasion of the Inauguration of LEP on 13 November 1989. The Large Electron-Positron (LEP) collider was inaugurated in the presence of some 1500 guests, including Heads of State and Ministers from all of CERN's 14 Member States.

  3. Le CERN fête le LEP

    CERN Document Server

    CERN Press Office. Geneva

    2000-01-01

    Members of government from around the world gathered at CERN on 9 October to celebrate the achievements of the Large Electron Positron collider (LEP), the Laboratory's flagship particle accelerator. Over the eleven years of its operational lifetime, LEP has not only added greatly to mankind's pool of knowledge about the Universe, but has also changed the way that particle physics research is done, and proved to be a valuable training ground for young professionals in many walks of life.

  4. Collide@CERN Geneva

    CERN Document Server

    CERN. Geneva; Kieffer, Robert; Blas Temino, Diego; Bertolucci, Sergio; Mr. Decelière, Rudy; Mr. Hänni, Vincent

    2014-01-01

    CERN, the Republic and Canton of Geneva, and the City of Geneva are delighted to invite you to “Collide@CERN Geneva Music”. Come to the public lecture about collisions between music and particle physics by the third winners of Collide@CERN Geneva, Vincent Hänni & Rudy Decelière, and their scientific inspiration partners, Diego Blas and Robert Kieffer. The event marks the beginning of their residency at CERN, and will be held at the CERN Globe of Science and Innovation on 16 October 2014 at 19.00. Doors will open at 18.30.

  5. LEP : the Large Electron Positron Collider Conference MT17

    CERN Multimedia

    2001-01-01

    LEP was CERN's flagship research facility from 1989 until 2000 when it stepped aside to make way for installation of the Laboratory's next major accelerator, the Large Hadron Collider, LHC. With a circumference of 27 kilometres, LEP was the largest circular particle collider in the world. Inside its beam pipe, about 100 metres underground, bunches of electrons and positrons raced around in opposite directions as they were accelerated to almost the speed of light. In its first phase of operation, LEP was designed to collide electrons and positrons at an energy of around 100 GeV. After some seven years of accumulating data at this energy to study the Z particle - electrically neutral carrier of the weak interaction - everything was done to boost the energy of LEP's beams as high as possible.

  6. Large hadron collider in the LEP tunnel. Proceedings. Vol. 2

    International Nuclear Information System (INIS)

    A Workshop, jointly organized by ECFA and CERN, took place at Lausanne and at CERN in March 1984 to study various options for a pp (or panti p) collider which might be installed at a later data alongside LEP in the LEP tunnel. Following the exploration of e+e- physics up to the highest energy now foreseeable, this would open up the opportunity to investigate hadron collisions in the new energy range of 10 to 20 TeV in the centre of mass. These proceedings put together the documents prepared in connection with this Workshop. They cover possible options for a Large Hadron Collider (LHC) in the LEP tunnel, the physics case as it stands at present, and studies of experimental possibilities in this energy range with luminosities as now considered. See hints under the relevant topics. (orig./HSI)

  7. CERN balances linear collider studies

    CERN Multimedia

    ILC Newsline

    2011-01-01

    The forces behind the two most mature proposals for a next-generation collider, the International Linear Collider (ILC) and the Compact Linear Collider (CLIC) study, have been steadily coming together, with scientists from both communities sharing ideas and information across the technology divide. In a support of cooperation between the two, CERN in Switzerland, where most CLIC research takes place, recently converted the project-specific position of CLIC Study Leader to the concept-based Linear Collider Study Leader.   The scientist who now holds this position, Steinar Stapnes, is charged with making the linear collider a viable option for CERN’s future, one that could include either CLIC or the ILC. The transition to more involve the ILC must be gradual, he said, and the redefinition of his post is a good start. Though not very much involved with superconducting radiofrequency (SRF) technology, where ILC researchers have made significant advances, CERN participates in many aspect...

  8. Collide@CERN - public lecture

    CERN Multimedia

    2012-01-01

    CERN, the Republic and Canton of Geneva and the City of Geneva are delighted to invite you to a public lecture by Gilles Jobin, first winner of the Collide@CERN Geneva Dance and Performance Artist-in-residence Prize, and his CERN inspiration partner, Joao Pequenao. They will present their work in dance and science at the Globe of Science and Innovation on Wednesday, 23 May 2012 at 7 p.m. (doors open at 6.30 p.m.).   
                                                  Programme 19:00 Opening address by - Professor Rolf-Dieter Heuer, CERN Director-General, - Ariane Koek...

  9. Collide@CERN: sharing inspiration

    CERN Multimedia

    Katarina Anthony

    2012-01-01

    Late last year, Julius von Bismarck was appointed to be CERN's first "artist in residence" after winning the Collide@CERN Digital Arts award. He’ll be spending two months at CERN starting this March but, to get a flavour of what’s in store, he visited the Organization last week for a crash course in its inspiring activities.   Julius von Bismarck, taking a closer look... When we arrive to interview German artist Julius von Bismarck, he’s being given a presentation about antiprotons’ ability to kill cancer cells. The whiteboard in the room contains graphs and equations that might easily send a non-scientist running, yet as Julius puts it, “if I weren’t interested, I’d be asleep”. Given his numerous questions, he must have been fascinated. “This ‘introduction’ week has been exhilarating,” says Julius. “I’ve been able to interact ...

  10. Large hadron collider project in CERN

    International Nuclear Information System (INIS)

    The Large Hadron Collider (LHC) is the latest scientific project in the world of particle physics launched by European Organization for Nuclear Research (CERN) nearby Geneva. The construction of the main components of this complex synchrotron ring where two proton beams will be accelerated up to energies of 7.7 TeV and then brought into collision, is well underway and the first installation of these components is expected to take place by the end of 2000. As a successor of the existing LEP machine and taking over a significant part of its infrastructure, when completed and commissioned in 2005, the LHG complex represent the most sophisticated and the largest project ever undertaken in the world of science. This machine has an ambitious task to offer the most contemporary and highest quality programmes in particle physics for scientists from all over the world. Its design and construction make use of the latest achievements in modern technologies, material sciences, engineering, computers, electronics and employing world wide experts and specialists of various profiles. At the same time, the LHC project ought to enable CERN and European scientists to maintain the world leading role in the field of particle physics in the next century. (author)

  11. Helium cryogenic systems for the LEP2 and LHC projects at CERN

    CERN Document Server

    Lebrun, P

    1996-01-01

    CERN is presently operating a large distributed 4.5 K helium cryogenic system (48 kW@4.5 K equivalent) for cooling the superconducting acceleration cavities of the 26.7 km circumference LEP2 lepton collider. This also constitutes the first part of the 1.8 K cryogenic system (about 150 kW@4.5 K equivalent) for the future Large Hadron Collider (LHC), the high-field superconducting magnets of which will operate in superfluid helium. We briefly describe the main features of each system, and review the progress of their development, construction and operation.

  12. The CERN LEP-SPS Librarian system

    International Nuclear Information System (INIS)

    The complexity of a software working environment, such as the control system for the SPS and LEP accelerators, requires a considerable management effort. The software needed to run the machines is continuously evolving, as new releases of application and system programs are introduced rather frequency. Ideally the management effort must coordinate all the different software developers and their users (the machine operating team). A software tool, the Librarian, has been written to help them in performing this task. Its ultimate goal is to enable the accelerator operators to retain control of all the software running in the control system. All the source files needed to produce a piece of running software (a 'product') are saved together, and can be retrieved either individually or as a whole. Management of the different versions of a product is also implemented, as well as a scheme for protections and access rights depending on the type of user (Librarian manager, application manager or software developer). The data base ORACLE has been used to maintain logical links between files saved under the Librarian. (orig.)

  13. Searches for the Standard Model Higgs boson at the LEP collider

    Science.gov (United States)

    Igo-Kemenes, Peter; Read, Alexander L.

    2016-10-01

    The Large Electron Positron (LEP) collider installed at CERN provided unprecedented possibilities for studying the properties of elementary particles during the years 1989-2000. The four detectors associated to the collider, run by the ALEPH, DELPHI, L3, and OPAL Collaborations, were based on the latest available technologies. The conjunction of high collision energies, precise instrumentation and data analysis techniques allowed the Standard Model (SM) of elementary particles to be tested at the level of quantum corrections. The search for new particles, in particular the long-sought Higgs boson, was one of the primary research subjects. During the twelve years of LEP, data samples of the highest quality and statistical weight were analysed. Concerning the search for the SM Higgs boson, the domain extending from zero mass to the kinematic limit imposed by the collider energy was scrutinised. The spirit of scientific competition gradually gave way to a collaborative effort, allowing the final results of LEP to be optimised. The methodology of Higgs boson searches is summarised in this paper together with the statistical methods adopted to combine the data of the four collaborations.

  14. Loans may keep CERN collider on target

    CERN Document Server

    Abbott, A

    1996-01-01

    The European Laboratory for Particle Physics (CERN) is considering taking out bank loans to fund its Large Hadron Collider project. CERN officials are evaluating this option in view of the German government's decision to substantially reduce its annual contributions to the project. They state that the bank loans may be the only way to complete the project by the year 2005, especially if other contributing nations follow Germany's lead.

  15. Charmed-hadron fragmentation functions from CERN LEP1 revisted

    International Nuclear Information System (INIS)

    In Phys. Rev. D 58, 014014 (1998) and 71, 094013 (2005), we determined non-perturbative D0, D+, D*+, Ds+, and Λc+ fragmentation functions, both at leading and next-to-leading order in the MS factorization scheme, by fitting e+e- data taken by the OPAL Collaboration at CERN LEP1. The starting points for the evolution in the factorization scale μ were taken to be μ0-2mQ, where Q = c, b. For the reader's convenience, in this Addendum, we repeat this analysis for μ0=mQ, where the flavor thresholds of modern sets of parton density functions are located. (Orig.)

  16. CERN collider glimpses supersymmetry - maybe

    CERN Multimedia

    Seife, C

    2000-01-01

    Particle physicists at CERN announced they may have witnessed supersymmetry. After smashing matter and antimatter in 4 experiments, they detected an anomaly in the resulting sprays of particles. It is consistent with supersymmetry but may yet prove t be a statistical fluctuation in the background data (1 page).

  17. Search for Higgs bosons at LEP2 and hadron colliders

    CERN Document Server

    Trefzger, T M

    2001-01-01

    The search for the Higgs boson was one of the most relevant issues of the final years of LEP running at high energies. An excess of 3 sigma beyond the background expectation has been found, consistent with the production of the Higgs boson with a mass near 115 GeV/c/sup 2/. At the upgraded Tevatron and at LHC the search for the Higgs boson will continue. At the Tevatron Higgs bosons can be detected with masses up to 180 GeV with an assumed total integrated luminosity of 20 fb/sup -1/. LHC has the potential to discover the Higgs boson in many different decay channels for Higgs masses up to 1 TeV. It will be possible to measure Higgs boson parameters, such as mass, width, and couplings to fermions and bosons. The results from Higgs searches at LEP2 and the possibilities for searches at hadron colliders will be reviewed. (156 refs).

  18. La fermeture du LEP retardee

    CERN Multimedia

    CERN Press Office. Geneva

    2000-01-01

    On 14 September 2000 CERN 's Director General Prof. Luciano Maiani, after a recommendation from the LEP Experiments Committee and the CERN Research Board, decided to extend the experimental run of the LEP accelerator until the 2nd November 2000. It was originally planned to conclude LEP's eleven year period of physics research at the end of September, and to begin the complex operations for the installation of CERN's new accelerator the Large Hadron Collider (LHC). However, exciting new results from the LEP experiments justify this change. The construction schedule for LHC will not be affected by this prolongation of LEP running.

  19. The Dismantling Project for the Large Electron Positron (LEP) Collider

    CERN Document Server

    Poole, John

    2002-01-01

    The LEP accelerator was installed in a circular tunnel 27 km in length with nine access points distributed around the circumference in the countryside and villages which surround CERN's sites. The dismantling project involved the removal in less than 15 months of around 29000 tonnes of equipment from the accelerator itself and a further 10000 tonnes from the four experiments - all of which were located at an average depth of 100 m below ground level. There was no contamination risk in the project and less than 3% of the materials removed were classified as radioactive. However, the materials which were classified as radioactive have to be temporarily stored and they consume considerable resources. The major difficulties for the project were in the establishment of the theoretical radiological zoning, implementation of the traceability systems and making appropriate radiation measurements to confirm the zoning. The absence of detailed guidelines from the French authorities, having no threshold levels for relea...

  20. LEP inauguration

    International Nuclear Information System (INIS)

    13 November saw the culmination at CERN of weeks of intricate planning to put together a fitting formal inauguration of LEP, CERN's 27-kilometre electron-positron collider. The day was to witness an event worthy of the many years of assiduous endeavour to bring into being the world's largest scientific machine, a prime example of international collaboration and the portent of a new era in fundamental research.

  1. Collide@CERN is looking for mentors

    CERN Multimedia

    2011-01-01

    The Collide@CERN Artist-in-Residence Programme is currently seeking CERN scientists interested in engaging in thought-provoking and creative collaborations with visiting artists.     In early 2012, a Digital artist will take up a 2-month residency and a Dance and Performance artist a 3-month residency.  Each artist will be allocated a specially selected science inspiration partner to work with. Both the artists and their mentors will give a public lecture in the Globe of Science and Innovation at the beginning and end of the residencies.  One scientist will be selected for each artist. Mentors and artists will be required to share knowledge by:   ·      Meeting once a week throughout the residency ·      Conducting online communications (such as a blog). If you are interested in becoming a mentor, please send the following information by e-m...

  2. At work on LEP, the world’s most powerful electron–positron collider

    CERN Multimedia

    Patrice Loiez,

    1999-01-01

    The LHC will be built inside the same tunnel as an existing accelerator, the Large Electron Positron (LEP) collider which came on stream in 1989. LEP will be removed from the tunnel at the end of this year to make way for the LHC. Here technicians make delicate adjustments to one of LEP’s thousands of magnets.

  3. Comedy Collider presents: No cause for conCERN

    CERN Multimedia

    Traczyk, Piotr

    2014-01-01

    Comedy Collider presents: No cause for conCERN was the highly anticipated follow up to LHComedy: CERN After Dark, starring an entirely new ensemble of comedy talent. Time: 13th June 2014, 19:30 for 20:00 Location: Globe of Science and Innovation, CERN, Geneva, Switzerland

  4. The LEP inauguration ceremony

    CERN Multimedia

    1989-01-01

    This photo was taken in November 1989 at the inauguration of the Large Electron-Positron (LEP) collider. From the left, Princess Margriet of the Netherlands, King Carl Gustav of Sweden, CERN Council President Josef Rembser, President Francois Mitterand of France, President Jean-Pascal Delamuraz of Switzerland, Carlo Rubbia, Director-General of CERN at the time.

  5. The ATLAS experiment at the CERN large hadron collider

    OpenAIRE

    Çetin, Serkant Ali; ATLAS Collaboration

    2008-01-01

    The ATLAS detector as installed in its experimental cavern at point 1 at CERN is described in this paper. A brief overview of the expected performance of the detector when the Large Hadron Collider begins operation is also presented.

  6. Ryoji Ikeda, Data Artist - Prix Ars Electronica Collide@CERN

    CERN Document Server

    CERN. Geneva; Koek, Ariane; Heuer, Rolf; Ikeda, Ryoji; Mr. Horst, Hoertner

    2014-01-01

    at the CERN Globe of Science and Innovation, CERN. You are very warmly invited to the opening presentation of Data Artist, Ryoji Ikeda’s residency at CERN. Ryoji Ikeda, one of the world’s leading electronic composers and visual artists, is the new Prix Ars Electronica Collide@CERN award winner. Ryoji Ikeda and his science inspiration partner, Theoretical Physicist, Dr. Tom Melia will talk about their work in arts and science. They are at the beginning of their creative journey together at CERN. A little about Ryoji Ikeda – the new Prix Ars Electronica Collide@CERN artist in residence. Ryoji Ikeda focuses on the essential characteristics of sound itself and that of visuals as light by means of both mathematical precision and mathematical aesthetics. Ikeda has gained a reputation as one of the few international artists working convincingly across both visual ...

  7. LEP superconducting cavities go into storage

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    Superconducting radio-frequency cavities from the LEP-2 phase (1996-2000) are put into storage in the tunnel that once housed the Intersecting Storage Rings (ISR), the world’s first proton collider, located at CERN.

  8. CERN Library | Mario Campanelli presents "Inside CERN's Large Hadron Collider" | 16 March

    CERN Multimedia

    CERN Library

    2016-01-01

    "Inside CERN's Large Hadron Collider" by Mario Campanelli. Presentation on Wednesday, 16 March at 4 p.m. in the Library (bldg 52-1-052) The book aims to explain the historical development of particle physics, with special emphasis on CERN and collider physics. It describes in detail the LHC accelerator and its detectors, describing the science involved as well as the sociology of big collaborations, culminating with the discovery of the Higgs boson.  Inside CERN's Large Hadron Collider  Mario Campanelli World Scientific Publishing, 2015  ISBN 9789814656641​

  9. From the CERN web: Collide@CERN, Fermilab neutrinos and more

    CERN Multimedia

    2015-01-01

    This new section highlights articles, blog posts and press releases published in the CERN web environment over the past weeks. This way, you won’t miss a thing...   Ruth Jarman and Joe Gerhardt. (Photo: Matthias H. Risse). Collide@CERN Ars Electronica Award goes to “Semiconductor” 10 August – Collide@CERN Ruth Jarman and Joe Gerhardt, two English artists collaborating under the name Semiconductor, are this year’s recipients of the Collide@CERN Ars Electronica Award. In the coming months, they will begin a two-month residency at CERN.  Continue to read…     Illustration: Fermilab/Sandbox Studio.   Fermilab experiment sees neutrinos change over 500 miles 7 August - Fermilab press release Scientists on the NOvA experiment saw their first evidence of oscillating neutrinos, confirming that the extraordinary detector built for the project not only functions as planned but is also making great p...

  10. Gilles Jobin Collide@CERN - Strangels Intervention

    CERN Multimedia

    Maximilien Brice

    2012-01-01

    STRANGELS Cie Gilles Jobin. Site specific choreographic intervention inside the CERN's library. Three strangels on a migration to another dimension rest at the CERN's library. Strangels need food for thoughts. Do not pay attention to them they are only strangels. Dancers : Ruth Childs, Susana Panadès Diaz, Gilles Jobin

  11. Lep vertical tunnel movements - lessons for future colliders

    Energy Technology Data Exchange (ETDEWEB)

    Pitthan, R. [CERN-Conseil Europeen pour la recherche nucleaire, Clic-Study Group and the Survey Group, Geneve (Switzerland)

    1999-07-01

    The data from 10 years of vertical surveys verify for all of LEP the previous observation, localized to region P1, that LEP floor movements are predominantly deterministic. This rules out the ATL model as being correct for this tunnel. If generalized, for yearly movements a random ATL model underestimates the possible maximum long-term motions. In contrast, extrapolation of the LEP vertical data to the short-term (hours and days) time-scale shows that the random approach predicts larger short-term movements than the deterministic model. This means that simulations using the ATL hypothesis are overtly pessimistic with regard to the frequency of operational realignments required. Depending on the constants chosen in the models these differences can be large, of the order of a magnitude and more. This paper deals solely with the directly measured months-to-years tunnel motions in rock, and the extrapolation of such ground motions to hourly or daily time-spans It does not, address the important question of the contribution of hourly-scale movements of the accelerator components, which could have a random part, to the combined motion. Nor does it address the question of movements of accelerator tunnels like HERA or TRISTAN which are built in water and debris, and not in solid rock. (author)

  12. Conclusions on 8 Years Operation of the LEP 4.5 K Refrigeration System at CERN

    CERN Document Server

    Bangert, N; Gayet, P; Sanmartí, M

    2002-01-01

    After 11 years of operation the Large Electron/Positron collider (LEP) was stopped in November 2000. Since 1993 a cryogenic system has been used to supply up to 72 superconducting (SC) cavity modules, using four large liquid-helium refrigerators at 4.5 K. We review eight years of operation of one of the world's largest helium cryogenic systems, its evolution and cooling capacity availability correlated to the LEP increasing energy program. Failure statistics, availability, recovery time after breakdowns and reliability are analyzed, and the most relevant problems encountered during the operation and their cure exposed. The operational organization is also briefly described.

  13. CERN-Fermilab Hadron Collider Physics Summer School

    CERN Multimedia

    2007-01-01

    Applications are now open for the 2nd CERN-Fermilab Hadron Collider Physics Summer School, which will take place at CERN from 6 to 15 June 2007. The school web site is http://cern.ch/hcpss with links to the academic program and application procedure. The application deadline is 9 March 2007. The results of the selection process will be announced shortly thereafter. The goal of the CERN-Fermilab Hadron Collider Physics Summer Schools is to offer students and young researchers in high energy physics a concentrated syllabus on the theory and experimental challenges of hadron collider physics. The first school in the series, held last summer at Fermilab, covered extensively the physics at the Tevatron collider experiments. The second school to be held at CERN, will focus on the technology and physics of the LHC experiments. Emphasis will be given on the first years of data-taking at the LHC and on the discovery potential of the programme. The series of lectures will be  supported by in-depth discussion sess...

  14. Quark radiation from LEP

    International Nuclear Information System (INIS)

    Like any other electrically charged particles, quarks should give out electromagnetic radiation (photons) when they vibrate. One of the physics results from CERN's LEP collider is the first clear observation of this quark radiation from electron-positron collisions. At lower energies this radiation could only be inferred

  15. The software for the CERN LEP beam orbit measurement system

    International Nuclear Information System (INIS)

    The Beam Orbit Measurement (BOM) system of LEP consists of 504 pickups, distributed all around the accelerator, that are capable of measuring the positions of the two beams. Their activity has to be synchronized, and the data produced by them have to be collected together, for example to form a 'closed orbit measurement' or a 'trajectory measurement'. On the user side, several clients can access simultaneously the results from this instrument. An automatic acquisition mode, and an 'on request' one, can run in parallel. This results in a very flexible and powerful system. The functionality of the BOM system is fully described, as well as the structure of the software processes which constitute the system, and their interconnections. Problems solved during the implementation are emphasized. (author)

  16. CERN completes magnet set for Large Hadron Collider

    CERN Multimedia

    2006-01-01

    "CERN, the European Oganization for Nuclear Research, took delivery of the last superconducting main magnet for the Large Hadron Collider (LHC) on Monday, completint the full set of 1624 main magnets required to build the world's largest and most powerful particle accelerator."

  17. Third intervention of Gilles Jobin and Collide@CERN

    CERN Multimedia

    2012-01-01

    Everything you wanted to know about contemporary dance but were afraid to ask. - 4 September 2012 at 4 p.m. in the Council Chamber -   A subjective and personal presentation of the recent history of contemporary dance by Gilles Jobin, Collide@CERN choreographer in residence.

  18. CERN to start Large Hadron Collider november 2007

    CERN Multimedia

    2006-01-01

    "The Large Hadron Collider (LHC) is expected to provide its first collisions in November 2007, CERN has announced. A two-month run at 0.9 TeV is planned for 2007 to test the accelerating and detecting equipment, and a full power run at 14 TeV is expected in the spring of 2008."

  19. EIB lends EUR 300 million for CERN's major collider

    CERN Document Server

    2002-01-01

    "The European Investment Bank (EIB) is lending EUR 300 million to finance the final phase of construction of the Large Hadron Collider (LHC) at CERN, the European Organization for Nuclear Research. The EIB loan will also help to finance the instrumentation to record and analyse the high-energy particle collisions at the LHC" (1 page).

  20. Search for Exotic Processes at the CERN pp Collider

    DEFF Research Database (Denmark)

    Ansari, R.; Bagnaia, P.; Banner, M.;......Kofoed-Hansen

    1987-01-01

    The total UA2 data sample at the CERN pp̄ Collider corresponds to an integrated luminosity of 910 nb−1. Limits on various hypothetical processes, such as production of excited electrons, additional charged or neutral vector bosons, or supersymmetric particles, are presented from the analysis...

  1. Collide@CERN: Horizons Irrésolus

    CERN Multimedia

    2016-01-01

    Sound Installation by Collide@CERN Geneva artists Rudy Decelière and Vincent Hänni in collaboration with physicists Diego Blas and Robert Kieffer, for the Electron Festival 25-27th March, 2016 (see here).   Horizons irrésolus is a sound installation that follows on the artistic residency Collide@CERN 2014.    Registration is absolutely required. Each guest will have to have registered using their own name. Guests without having registered will not be able to come into CERN. Free entrance: Book here  A shuttle will be available every 15 minutes from 6 p.m. until 9 p.m. from CERN Reception (in front of CERN Globe) to the sound art installation. Access from Geneva to CERN Reception by tram 18, end of the line. With the support from The Republic and Canton of Geneva and The City of Geneva. Find out more on the artists and their Geneva 2...

  2. Russian plant grows monocrystals for CERN collider

    CERN Multimedia

    2003-01-01

    "..Experts of an enterprise in Murmansk Region has started to make so-called monocrystals. They are needed for making of a huge device the construction of which has started in Switzerland. Thanks to this unique equipment scientists of the European Organization for Nuclear Research (CERN) will be able to model the creation of the universe for the first time ever" (1/2 page).

  3. 2nd CERN-Fermilab Hadron Collider Physics Summer School

    CERN Multimedia

    2007-01-01

    June 6-15, 2007, CERN The school web site is http://cern.ch/hcpss with links to the academic programme and the application procedure. The APPLICATION DEADLINE IS 9 MARCH 2007 The results of the selection process will be announced shortly thereafter. The goal of the CERN-Fermilab Hadron Collider Physics Summer Schools is to offer students and young researchers in high energy physics a concentrated syllabus on the theory and experimental challenges of hadron collider physics. The first school in the series, held last summer at Fermilab, extensively covered the physics at the Tevatron collider experiments. The second school, to be held at CERN, will focus on the technology and physics of the LHC experiments. Emphasis will be placed on the first years of data-taking at the LHC and on the discovery potential of the programme. The series of lectures will be supported by in-depth discussion sessions and will include the theory and phenomenology of hadron collisions, discovery physics topics, detector and analysis t...

  4. A Large Hadron Electron Collider at CERN

    CERN Document Server

    Abelleira Fernandez, J L; Adzic, P; Akay, A N; Aksakal, H; Albacete, J L; Allanach, B; Alekhin, S; Allport, P; Andreev, V; Appleby, R B; Arikan, E; Armesto, N; Azuelos, G; Bai, M; Barber, D; Bartels, J; Behnke, O; Behr, J; Belyaev, A S; Ben-Zvi, I; Bernard, N; Bertolucci, S; Bettoni, S; Biswal, S; Blumlein, J; Bottcher, H; Bogacz, A; Bracco, C; Bracinik, J; Brandt, G; Braun, H; Brodsky, S; Bruning, O; Bulyak, E; Buniatyan, A; Burkhardt, H; Cakir, I T; Cakir, O; Calaga, R; Caldwell, A; Cetinkaya, V; Chekelian, V; Ciapala, E; Ciftci, R; Ciftci, A K; Cole, B A; Collins, J C; Dadoun, O; Dainton, J; Roeck, A.De; d'Enterria, D; DiNezza, P; Dudarev, A; Eide, A; Enberg, R; Eroglu, E; Eskola, K J; Favart, L; Fitterer, M; Forte, S; Gaddi, A; Gambino, P; Garcia Morales, H; Gehrmann, T; Gladkikh, P; Glasman, C; Glazov, A; Godbole, R; Goddard, B; Greenshaw, T; Guffanti, A; Guzey, V; Gwenlan, C; Han, T; Hao, Y; Haug, F; Herr, W; Herve, A; Holzer, B J; Ishitsuka, M; Jacquet, M; Jeanneret, B; Jensen, E; Jimenez, J M; Jowett, J M; Jung, H; Karadeniz, H; Kayran, D; Kilic, A; Kimura, K; Klees, R; Klein, M; Klein, U; Kluge, T; Kocak, F; Korostelev, M; Kosmicki, A; Kostka, P; Kowalski, H; Kraemer, M; Kramer, G; Kuchler, D; Kuze, M; Lappi, T; Laycock, P; Levichev, E; Levonian, S; Litvinenko, V N; Lombardi, A; Maeda, J; Marquet, C; Mellado, B; Mess, K H; Milanese, A; Milhano, J G; Moch, S; Morozov, I I; Muttoni, Y; Myers, S; Nandi, S; Nergiz, Z; Newman, P R; Omori, T; Osborne, J; Paoloni, E; Papaphilippou, Y; Pascaud, C; Paukkunen, H; Perez, E; Pieloni, T; Pilicer, E; Pire, B; Placakyte, R; Polini, A; Ptitsyn, V; Pupkov, Y; Radescu, V; Raychaudhuri, S; Rinolfi, L; Rizvi, E; Rohini, R; Rojo, J; Russenschuck, S; Sahin, M; Salgado, C A; Sampei, K; Sassot, R; Sauvan, E; Schaefer, M; Schneekloth, U; Schorner-Sadenius, T; Schulte, D; Senol, A; Seryi, A; Sievers, P; Skrinsky, A N; Smith, W; South, D; Spiesberger, H; Stasto, A M; Strikman, M; Sullivan, M; Sultansoy, S; Sun, Y P; Surrow, B; Szymanowski, L; Taels, P; Tapan, I; Tasci, T; Tassi, E; Kate, H.Ten; Terron, J; Thiesen, H; Thompson, L; Thompson, P; Tokushuku, K; Tomas Garcia, R; Tommasini, D; Trbojevic, D; Tsoupas, N; Tuckmantel, J; Turkoz, S; Trinh, T N; Tywoniuk, K; Unel, G; Ullrich, T; Urakawa, J; VanMechelen, P; Variola, A; Veness, R; Vivoli, A; Vobly, P; Wagner, J; Wallny, R; Wallon, S; Watt, G; Weiss, C; Wiedemann, U A; Wienands, U; Willeke, F; Xiao, B W; Yakimenko, V; Zarnecki, A F; Zhang, Z; Zimmermann, F; Zlebcik, R; Zomer, F; CERN. Geneva. LHeC Department

    2012-01-01

    This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and electron-ion physics. The LHeC is designed to run synchronously with the LHC in the twenties and to achieve an integrated luminosity of O(100) fb$^{-1}$. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC.

  5. Are there indications of compositeness of leptons and quarks in CERN LEP data?

    CERN Document Server

    Elfgren, Erik

    2007-01-01

    The ``preon-trinity'' model for the compositeness of leptons, quarks and heavy vector bosons predicts several new heavy leptons and quarks. Three of them can be produced in $e^{+}e^{-}$ annihilations at CERN LEP energies, since they can be created out of a system of three preons and their antipreons, where three preons form a heavy lepton or quark, while the other three go into a normal lepton or quark. In fact, these new particles are predicted to be lighter than the top quark, while the top itself cannot be produced this way, due to its particular preon substructure. The empirical situation is analyzed, and the most likely masses are estimated.

  6. The fastbus trigger modules for the SAT detector in the DELPHI experiment at LEP, CERN

    Energy Technology Data Exchange (ETDEWEB)

    Alvsvaag, S.J.

    1992-09-01

    This thesis describes the functionality and performance of the fastbus trigger modules for the Small Angle Tagger (SAT) detector in the DELPHI experiment at the LEP machine at CERN. The main purpose of the modules is to provide a Bhabha trigger for the SAT calorimeter used for luminosity measurements. The author has bee responsible for the design, production, testing and installation of the trigger modules. All the test programs necessary to confirm that the modules function according to the specifications are included in this work. Is does not, however, aim to make detailed technical descriptions of the modules. 44 refs., 39 figs., 18 tabs.

  7. CERN accelerator school: Antiprotons for colliding beam facilities

    International Nuclear Information System (INIS)

    This is a specialized course which addresses a wide spectrum of theoretical and technological problems confronting the designer of an antiproton facility for high-energy-physics research. A broad and profound basis is provided by the lecturers' substantial experience gained over many years with CERN's unique equipment. Topics include beam optics, special lattices for antiproton accumulation and storage rings, antiproton production, stochastic cooling, acceleration and storage, r.f. noise, r.f. beam manipulations, beam-beam interaction, beam stability due to ion accumulation, and diagnostics. The SPS (Super Proton Synchrotron) panti p collider, LEAR (the Low Energy Antiproton Ring at CERN), antiprotons in the ISR (Intersecting Storage Rings), the new antiproton collector (ACOL) and gas jet targets are also discussed. A table is included listing the parameters of all CERN's accelerators and storage rings. See hints under the relevant topics. (orig./HSI)

  8. Heavy quark and quarkonium production at CERN LEP2: k_T-factorization versus data

    CERN Document Server

    Lipatov, A V

    2004-01-01

    We present calculations of heavy quark and quarkonium production at CERN LEP2 in the k_T-factorization QCD approach. Both direct and resolved photon contribution are taken into account. The conservative error analisys is performed. The unintegrated gluon distribution in the photon is taken from the full CCFM evolution equation. The traditional color-singlet mechanism to describe non-perturbative transition of heavy quark pair into a final quarkonium is used. Our analisys covers polarization properties of heavy quarkonia at moderate and large transverse momenta. We find that the total and differential open charm production cross sections are consistent with the recent experimental data taken by the L3, OPAL and ALEPH collaborations. At the same time the DELPHI data for the inclusive J/Psi production exceed our predictions but experimental uncertainties are too large to claim a significant inconsistency. The bottom production in photon-photon collisions at CERN LEP2 is hard to explain within the k_T-factorizati...

  9. Greece at CERN

    CERN Multimedia

    CERN Press Office. Geneva

    1997-01-01

    Greece, one of CERN*'s founding Member States, inaugurated its first Industrial Exhibition at the Meyrin site on Tuesday, 14 October. After a meeting with CERN's Director General, Professor Christopher Llewellyn Smith, Professor Emmanuel Frangoulis, the General Secretary of the Greek Ministry of Industry, accompanied by Prof Emmanuel Floratos, Greek delegate to CERN council visited the DELPHI experiment on the LEP collider, guided by Andromachi Tsirou, a Greek physicist.

  10. LEP dominates LP-HEP

    International Nuclear Information System (INIS)

    CERN's LEP electron-positron collider was the star of this year's major physics meeting - the Joint International Lepton-Photon Symposium and Europhysics Conference on High Energy Physics (LP-HEP) - held in Geneva from 25 July - 1 August

  11. 3rd CERN-Fermilab Hadron Collider Physics Summer School

    CERN Multimedia

    2008-01-01

    August 12-22, 2008, Fermilab The school web site is http://cern.ch/hcpss with links to the academic programme and the application procedure. The APPLICATION DEADLINE IS 29 FEBRUARY 2008. The goal of the CERN-Fermilab Hadron Collider Physics Summer Schools is to offer students and young researchers in high-energy physics a concentrated syllabus on the theory and experimental challenges of hadron collider physics. The third session of the summer school will focus on exposing young post-docs and advanced graduate students to broader theories and real data beyond what they’ve learned at their home institutions. Experts from across the globe will lecture on the theoretical and experimental foundations of hadron collider physics, host parallel discussion sessions and answer students’ questions. This year’s school will also have a greater focus on physics beyond the Standard Model, as well as more time for questions at the end of each lecture. The 2008 School will be held at ...

  12. Complementarity of the CERN Large Hadron Collider and the $e^+e^-$ International Linear Collider

    CERN Document Server

    Choi, S Y

    2008-01-01

    The next-generation high-energy facilities, the CERN Large Hadron Collider (LHC) and the prospective $e^+e^-$ International Linear Collider (ILC), are expected to unravel new structures of matter and forces from the electroweak scale to the TeV scale. In this report we review the complementary role of LHC and ILC in drawing a comprehensive and high-precision picture of the mechanism breaking the electroweak symmetries and generating mass, and the unification of forces in the frame of supersymmetry.

  13. Influence of the transverse beam sizes on the ep -> ep. gamma. cross section at the HERA and a FUTURE CERN electron-proton collider

    Energy Technology Data Exchange (ETDEWEB)

    Kotkin, G.L.; Polityko, S.I.; Serbo, V.G.; Schiller, A.

    1988-06-01

    In the process ep -> ep..gamma.., proposed for luminosity measurements at HERA, impact parameters occur which are larger than the transverse beam sizes in the ep-colliders in HERA and a CERN option (LHC+LEP). This decreases the number of observed photons compared to the standard QED calculation. The difference is larger than 10% at photon energies E/sub ..gamma../ < 0.4E/sub e/ for the CERN option and E/sub ..gamma../ < 0.01E/sub e/ for HERA. (orig.)

  14. Physics at LEP

    International Nuclear Information System (INIS)

    This report surveys physics which may be investigated at LEP, the Large Electron-Positron collider under construction at CERN. Five general areas are emphasized, namely: precision measurements at the Z0 peak; studies of toponium; searches for possible new particles; QCD, γγ, and heavy quark studies; and experiments at the highest LEP energies up to and beyond the W+W- pair-production threshold. Wherever possible, full cross section formulae are given, together with references to the original literature where more details may be found. (orig.)

  15. The CERN Antiproton Collider Programme Accelerators and Accumulation Rings

    CERN Document Server

    Koziol, Heribert

    2004-01-01

    One of CERN's most daring and successful undertakings was the quest for the intermediate bosons, W and Z. In this paper, we describe the accelerator part of the venture which relied on a number of innovations: an extension of the budding method of stochastic cooling by many orders of magnitude; the construction of the Antiproton Accumulator, depending on several novel accelerator methods and technologies; major modifications to the 26 GeV PS Complex; and the radical conversion of the 300 GeV SPS, which just had started up as an accelerator, to a protonâ€"antiproton collider. The SPS Collider had to master the beamâ€"beam effect far beyond limits reached ever before and had to function in a tight symbiosis with the huge detectors UA1 and UA2.

  16. LEP3: A High Luminosity e+e- Collider to study the Higgs Boson

    CERN Document Server

    Blondel, A; Assmann, R W; Butterworth, A; Janot, P; Jimenez, J M; Grojean, C; Milanese, A; Modena, M; Osborne, J A; Zimmermann, F; Piekarz, H; Oide, K; Yokoya, K; Ellis, J; Klute, M; Zanetti, M; Velasco, M; Telnov, V; Rivkin, L; Murray, B; Cai, Y

    2012-01-01

    The LHC experiments discovered a new particle of mass around 125 GeV, candidate for the scalar Higgs boson of the Standard Model. An e+e- collider operating close to the ZH threshold could be the tool of choice for studying this unique particle in detail. We present here the concept of a storage ring collider, which we call LEP3. Preliminary studies show that at a centre-of-mass energy of 240 GeV, near-constant luminosities of 10^34 cm^{-2}s^{-1} are possible in up to four collision points, while respecting a number of constraints including beamstrahlung. The integrated luminosity is 100fb^{-1}/y per interaction point, 20,000 e+e- --> ZH events would be produced per year and per experiment. LEP3 could also operate in multi-bunch mode at the Z resonance, with luminosities of several\\times10^35 cm^{-2}s^{-1}, yielding O(10^11) Z decays per year, as well as just above the WW threshold. The short luminosity lifetime requires the use of top-up injection, which, in turn calls for a full-energy injector. The present...

  17. LEP3: A High Luminosity e+e- Collider to Study the Higgs Boson

    CERN Document Server

    Blondel, A U; Assmann, R W; Butterworth, A; Janot, P; Jimenez, J M; Grojean, C; Milanese, A; Modena, M; Osborne, J A; Zimmermann, F; Piekarz, H; Oide, K; Yokoya, K; Ellis, J; Klute, M; Zanetti, M; Velasco, M; Telnov, V; Rivkin, L; Cai, Y

    2012-01-01

    The LHC experiments have discovered a new particle with a mass around 125 GeV that is a strong candidate for the scalar Higgs boson expected in the Standard Model. An e+e− collider operating close to the ZH threshold (at a centre-of-mass energy of 240 GeV) could be the tool of choice for studying this unique particle in detail. We present here the concept of a storage ring collider, which we call LEP3. Preliminary studies show that at a centre-of-mass energy of 240 GeV, near-constant luminosities of 1034 cm-2s-1 are possible in up to four collision points, while respecting a number of constraints including beamstrahlung limits. With an integrated luminosity of 100fb-1 per year and per interaction point, 20,000 e+e- - ZH events would be produced per year and per experiment. LEP3 could also operate in multi-bunch mode at the Z resonance, with luminosities of several×1035cm-2s-1, yielding O(1011) Z decays per year, as well as just above the WW threshold, potentially improving our knowledge of W and Z propert...

  18. 2nd CERN-Fermilab Hadron Collider Physics Summer School, June 6-15, 2007, CERN

    CERN Multimedia

    2007-01-01

    The school web site is http://cern.ch/hcpss with links to the academic programme and the application procedure. The APPLICATION DEADLINE IS 9 MARCH 2007. The results of the selection process will be announced shortly thereafter. The goal of the CERN-Fermilab Hadron Collider Physics Summer Schools is to offer students and young researchers in high energy physics a concentrated syllabus on the theory and experimental challenges of hadron collider physics. The first school in the series, held last summer at Fermilab, covered extensively the physics at the Tevatron collider experiments. The second school, to be held at CERN, will focus on the technology and physics of the LHC experiments. Emphasis will be placed on the first years of data-taking at the LHC and on the discovery potential of the programme. The series of lectures will be supported by in-depth discussion sessions and will include the theory and phenomenology of hadron collisions, discovery physics topics, detector and analysis techniques and tools...

  19. Help LEP

    CERN Multimedia

    Carreras,R; Lehmann,P

    1988-01-01

    première partie: Help LEP ou le tunnel de l'infini- pièce radiophonique intéréssant sur l'origine de la matière deuxième partie: Help LEP débat; suite à cette pièce interview avec 3 physiciens du Cern sur le projet LEP et le but du Cern qui est la recherche fondamentale

  20. Premiers résultats en provenance du LEP2

    CERN Multimedia

    CERN Press Office. Geneva

    1996-01-01

    CERN's Large Electron-Positron collider, LEP, produced its first pair of fundamental particles known as W+ and W- today, taking particle physics research into new and unexplored territory. This follows a busy winter of upgrades which have transformed LEP into a new accelerator, earning it the name LEP2. Hundreds of physicists from all over the world come to CERN to do their research at LEP2, which will be further upgraded over the coming years, bringing the possibility of new discoveries and extending our understanding of the Universe.

  1. The LEP impedance model

    Energy Technology Data Exchange (ETDEWEB)

    Zotter, B. [European Organization for Nuclear Research, Geneva (Switzerland)

    1996-08-01

    This report describes a number of measurements and computations of the impedance of the Large Electron Positron collider LEP at CERN. The work has been performed over several years, together with D. Brandt, K. Cornelis, A. Hofmann, G. Sabbi and many others. The agreement between measurements of single bunch instabilities on the machine and computer simulations is in general excellent and gives confidence in the impedance model used. (author)

  2. Recent results from LEP

    Indian Academy of Sciences (India)

    A Gurtu

    2000-04-01

    Recent results from the LEP collider at CERN are presented: on the identification of +- → +- and the determination of the mass and width and limits on its anomalous couplings; the search for the Standard Model and non-minimal Higgs; search for SUSY and other new particles. Fits to all electroweak data leading to predictions of the Higgs mass within the Standard Model are presented.

  3. LEP copper accelerating cavities

    CERN Multimedia

    Laurent Guiraud

    1999-01-01

    These copper cavities were used to generate the radio frequency electric field that was used to accelerate electrons and positrons around the 27-km Large Electron-Positron (LEP) collider at CERN, which ran from 1989 to 2000. The copper cavities were gradually replaced from 1996 with new superconducting cavities allowing the collision energy to rise from 90 GeV to 200 GeV by mid-1999.

  4. [European particle accelerator conference, Rome, Italy, and visit to the LEP storage ring and LEP detectors L3 and ALEPH at CERN, Geneva, Switzerland, June 5-16, 1988]: Foreign trip report

    International Nuclear Information System (INIS)

    A selection of papers presented at the EPAC Conference relating to accelerator technology, facilities proposed, planned or under construction, and operating machines are discussed. Also noted are discussions at CERN with personnel from the LEP superconducting RF, the LEP L3 and ALEPH detectors, and the LHC superconducting magnet groups

  5. Supersymmetric particles at the CERN p anti p collider

    International Nuclear Information System (INIS)

    We explore the experimental missing psub(T) signatures for squark qtilde and gluino gtilde production at the CERN panti p Collider. We present topological cross-sections for gtildegtilde(anti qtilde) production followed by gtilde -> anti qγtilde (qtilde -> qγtilde) decay, applying criteria for the jet trigger and specification modelled on those used by UA1. Gluinos or squarks with masses less than about 40 GeV give events with missing psub(T), predominantly one-jet events, -fewer two- and multijet events. We use the observed monojet events as an upper limit implying msub(g)tilde (msub(q)tilde) > or approx. 40 GeV. The observed one- and multijet events could be due to the production of gtildegtilde or qtildeanti qtilde with msub(g)tilde or msub(q)tilde = 0(40)GeV. The small invariant masses of the observed monojets and their hard missing psub(T) spectrum favour a qtilde interpretation. Predictions are presented for msub(g)tilde or msub(q)tilde up to 60 GeV which could be detectable in forthcoming data from the CERN panti p collider. (orig.)

  6. The LEP groundbreaking ceremony

    CERN Multimedia

    1983-01-01

    French President Francois Mitterand and Swiss President Pierre Aubert visiting CERN for the LEP ground-breaking ceremony on 13 September 1983. They are seen here with Emilio Picasso, LEP project director, and Herwig Schopper, CERN's then Director-General.

  7. Civil Engineering Feasibility Studies for Future Ring Colliders at CERN

    CERN Document Server

    Bruning, O; Myers, S; Osborne, J; Rossi, L; Waaijer, C; Zimmermann, F

    2013-01-01

    CERN civil engineers are studying the feasibility of several potential ring colliders to complement the LHC: an 80km circular tunnel to house the TLEP and VHE-LHC, and the ring-ring and linac-ring options for the LHeC. The feasibility of these projects is largely dependent on civil design and geotechnical and environmental risks. As civil infrastructure works typically represent one third of the cost of major physics projects, it is critical that the construction costs are well understood from the conceptual stage. This proceeding presents the first results of the feasibility studies for the 80km tunnel and the linac-ring LHeC. Presented at IPAC'13 Shanghai, 12-17 May 2013

  8. Art and science interactions - First Collide @CERN public lecture by Julius Von Bismarck

    CERN Document Server

    CERN. Geneva

    2012-01-01

    Creative collisions between the arts and science have begun at CERN with the first Collide@CERN artist, Julius Von Bismarck starting his digital arts residency at the world's largest particle physics laboratory outside Geneva. He was chosen from 395 entries from 40 countries around the world from the Prix Ars Electronica Collide@CERN competition launched last September 2011. To mark this special occasion, the first Collide@CERN public lecture open to everyone will take place on March 21st 2012 at CERN's Globe of Science and Innovation, with a drinks reception at 18.45 and with presentations starting at 19.30. The event is free and will be opened by the Director General of CERN, Professor Rolf-Dieter Heuer and Gerfried Stocker, the Artistic Director of Ars Electronica, Linz, - CERN's international cultural partners for the digital arts Collide@CERN award known as Prix Ars Electronica Collide@CERN in recognition of our joint partnership. Julius Von Bismarck and his CERN science inspiration partner, the physic...

  9. Beyond the Large Hadron Collider: a first look at cryogenics for CERN future circular colliders

    CERN Document Server

    Lebrun, Ph

    2015-01-01

    Following the first experimental discoveries at the Large Hadron Collider (LHC) and the recent update of the European strategy in particle physics, CERN has undertaken an international study of possible future circular colliders beyond the LHC. The study, conducted with the collaborative participation of interested institutes world-wide, considers several options for very high energy hadron-hadron, electron-positron and hadron-electron colliders to be installed in a quasi-circular underground tunnel in the Geneva basin, with a circumference of 80 km to 100 km. All these machines would make intensive use of advanced superconducting devices, i.e. high-field bending and focusing magnets and/or accelerating RF cavities, thus requiring large helium cryogenic systems operating at 4.5 K or below. Based on preliminary sets of parameters and layouts for the particle colliders under study, we discuss the main challenges of their cryogenic systems and present first estimates of the cryogenic refrigeration capacities req...

  10. Study of cosmic ray events with high muon multiplicity using the ALICE detector at the CERN Large Hadron Collider

    CERN Document Server

    AUTHOR|(CDS)2073687; Adamova, Dagmar; Aggarwal, Madan Mohan; Aglieri Rinella, Gianluca; Agnello, Michelangelo; Agrawal, Neelima; Ahammed, Zubayer; Ahn, Sang Un; Aiola, Salvatore; Akindinov, Alexander; Alam, Sk Noor; Aleksandrov, Dmitry; Alessandro, Bruno; Alexandre, Didier; Alfaro Molina, Jose Ruben; Alici, Andrea; Alkin, Anton; Millan Almaraz, Jesus Roberto; Alme, Johan; Alt, Torsten; Altinpinar, Sedat; Altsybeev, Igor; Alves Garcia Prado, Caio; Andrei, Cristian; Andronic, Anton; Anguelov, Venelin; Anielski, Jonas; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Aphecetche, Laurent Bernard; Appelshaeuser, Harald; Arcelli, Silvia; Armesto Perez, Nestor; Arnaldi, Roberta; Arsene, Ionut Cristian; Arslandok, Mesut; Audurier, Benjamin; Augustinus, Andre; Averbeck, Ralf Peter; Azmi, Mohd Danish; Bach, Matthias Jakob; Badala, Angela; Baek, Yong Wook; Bagnasco, Stefano; Bailhache, Raphaelle Marie; Bala, Renu; Baldisseri, Alberto; Baltasar Dos Santos Pedrosa, Fernando; Baral, Rama Chandra; Barbano, Anastasia Maria; Barbera, Roberto; Barile, Francesco; Barnafoldi, Gergely Gabor; Barnby, Lee Stuart; Ramillien Barret, Valerie; Bartalini, Paolo; Barth, Klaus; Bartke, Jerzy Gustaw; Bartsch, Esther; Basile, Maurizio; Bastid, Nicole; Basu, Sumit; Bathen, Bastian; Batigne, Guillaume; Batista Camejo, Arianna; Batyunya, Boris; Batzing, Paul Christoph; Bearden, Ian Gardner; Beck, Hans; Bedda, Cristina; Belikov, Iouri; Bellini, Francesca; Bello Martinez, Hector; Bellwied, Rene; Belmont Iii, Ronald John; Belmont Moreno, Ernesto; Belyaev, Vladimir; Bencedi, Gyula; Beole, Stefania; Berceanu, Ionela; Bercuci, Alexandru; Berdnikov, Yaroslav; Berenyi, Daniel; Bertens, Redmer Alexander; Berzano, Dario; Betev, Latchezar; Bhasin, Anju; Bhat, Inayat Rasool; Bhati, Ashok Kumar; Bhattacharjee, Buddhadeb; Bhom, Jihyun; Bianchi, Livio; Bianchi, Nicola; Bianchin, Chiara; Bielcik, Jaroslav; Bielcikova, Jana; Bilandzic, Ante; Biswas, Rathijit; Biswas, Saikat; Bjelogrlic, Sandro; Blair, Justin Thomas; Blanco, Fernando; Blau, Dmitry; Blume, Christoph; Bock, Friederike; Bogdanov, Alexey; Boggild, Hans; Boldizsar, Laszlo; Bombara, Marek; Book, Julian Heinz; Borel, Herve; Borissov, Alexander; Borri, Marcello; Bossu, Francesco; Botta, Elena; Boettger, Stefan; Braun-Munzinger, Peter; Bregant, Marco; Breitner, Timo Gunther; Broker, Theo Alexander; Browning, Tyler Allen; Broz, Michal; Brucken, Erik Jens; Bruna, Elena; Bruno, Giuseppe Eugenio; Budnikov, Dmitry; Buesching, Henner; Bufalino, Stefania; Buncic, Predrag; Busch, Oliver; Buthelezi, Edith Zinhle; Bashir Butt, Jamila; Buxton, Jesse Thomas; Caffarri, Davide; Cai, Xu; Caines, Helen Louise; Calero Diaz, Liliet; Caliva, Alberto; Calvo Villar, Ernesto; Camerini, Paolo; Carena, Francesco; Carena, Wisla; Carnesecchi, Francesca; Castillo Castellanos, Javier Ernesto; Castro, Andrew John; Casula, Ester Anna Rita; Cavicchioli, Costanza; Ceballos Sanchez, Cesar; Cepila, Jan; Cerello, Piergiorgio; Cerkala, Jakub; Chang, Beomsu; Chapeland, Sylvain; Chartier, Marielle; Charvet, Jean-Luc Fernand; Chattopadhyay, Subhasis; Chattopadhyay, Sukalyan; Chelnokov, Volodymyr; Cherney, Michael Gerard; Cheshkov, Cvetan Valeriev; Cheynis, Brigitte; Chibante Barroso, Vasco Miguel; Dobrigkeit Chinellato, David; Cho, Soyeon; Chochula, Peter; Choi, Kyungeon; Chojnacki, Marek; Choudhury, Subikash; Christakoglou, Panagiotis; Christensen, Christian Holm; Christiansen, Peter; Chujo, Tatsuya; Chung, Suh-Urk; Zhang, Chunhui; Cicalo, Corrado; Cifarelli, Luisa; Cindolo, Federico; Cleymans, Jean Willy Andre; Colamaria, Fabio Filippo; Colella, Domenico; Collu, Alberto; Colocci, Manuel; Conesa Balbastre, Gustavo; Conesa Del Valle, Zaida; Connors, Megan Elizabeth; Contreras Nuno, Jesus Guillermo; Cormier, Thomas Michael; Corrales Morales, Yasser; Cortes Maldonado, Ismael; Cortese, Pietro; Cosentino, Mauro Rogerio; Costa, Filippo; Crochet, Philippe; Cruz Albino, Rigoberto; Cuautle Flores, Eleazar; Cunqueiro Mendez, Leticia; Dahms, Torsten; Dainese, Andrea; Danu, Andrea; Das, Debasish; Das, Indranil; Das, Supriya; Dash, Ajay Kumar; Dash, Sadhana; De, Sudipan; De Caro, Annalisa; De Cataldo, Giacinto; De Cuveland, Jan; De Falco, Alessandro; De Gruttola, Daniele; De Marco, Nora; De Pasquale, Salvatore; Deisting, Alexander; Deloff, Andrzej; Denes, Ervin Sandor; D'Erasmo, Ginevra; Dhankher, Preeti; Di Bari, Domenico; Di Mauro, Antonio; Di Nezza, Pasquale; Diaz Corchero, Miguel Angel; Dietel, Thomas; Dillenseger, Pascal; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Dobrowolski, Tadeusz Antoni; Domenicis Gimenez, Diogenes; Donigus, Benjamin; Dordic, Olja; Drozhzhova, Tatiana; Dubey, Anand Kumar; Dubla, Andrea; Ducroux, Laurent; Dupieux, Pascal; Ehlers Iii, Raymond James; Elia, Domenico; Engel, Heiko; Epple, Eliane; Erazmus, Barbara Ewa; Erdemir, Irem; Erhardt, Filip; Espagnon, Bruno; Estienne, Magali Danielle; Esumi, Shinichi; Eum, Jongsik; Evans, David; Evdokimov, Sergey; Eyyubova, Gyulnara; Fabbietti, Laura; Fabris, Daniela; Faivre, Julien; Fantoni, Alessandra; Fasel, Markus; Feldkamp, Linus; Felea, Daniel; Feliciello, Alessandro; Feofilov, Grigorii; Ferencei, Jozef; Fernandez Tellez, Arturo; Gonzalez Ferreiro, Elena; Ferretti, Alessandro; Festanti, Andrea; Feuillard, Victor Jose Gaston; Figiel, Jan; Araujo Silva Figueredo, Marcel; Filchagin, Sergey; Finogeev, Dmitry; Fionda, Fiorella; Fiore, Enrichetta Maria; Fleck, Martin Gabriel; Floris, Michele; Foertsch, Siegfried Valentin; Foka, Panagiota; Fokin, Sergey; Fragiacomo, Enrico; Francescon, Andrea; Frankenfeld, Ulrich Michael; Fuchs, Ulrich; Furget, Christophe; Furs, Artur; Fusco Girard, Mario; Gaardhoeje, Jens Joergen; Gagliardi, Martino; Gago Medina, Alberto Martin; Gallio, Mauro; Gangadharan, Dhevan Raja; Ganoti, Paraskevi; Gao, Chaosong; Garabatos Cuadrado, Jose; Garcia-Solis, Edmundo Javier; Gargiulo, Corrado; Gasik, Piotr Jan; Gauger, Erin Frances; Germain, Marie; Gheata, Andrei George; Gheata, Mihaela; Ghosh, Premomoy; Ghosh, Sanjay Kumar; Gianotti, Paola; Giubellino, Paolo; Giubilato, Piero; Gladysz-Dziadus, Ewa; Glassel, Peter; Gomez Coral, Diego Mauricio; Gomez Ramirez, Andres; Gonzalez Zamora, Pedro; Gorbunov, Sergey; Gorlich, Lidia Maria; Gotovac, Sven; Grabski, Varlen; Graczykowski, Lukasz Kamil; Graham, Katie Leanne; Grelli, Alessandro; Grigoras, Alina Gabriela; Grigoras, Costin; Grigoryev, Vladislav; Grigoryan, Ara; Grigoryan, Smbat; Grynyov, Borys; Grion, Nevio; Grosse-Oetringhaus, Jan Fiete; Grossiord, Jean-Yves; Grosso, Raffaele; Guber, Fedor; Guernane, Rachid; Guerzoni, Barbara; Gulbrandsen, Kristjan Herlache; Gulkanyan, Hrant; Gunji, Taku; Gupta, Anik; Gupta, Ramni; Haake, Rudiger; Haaland, Oystein Senneset; Hadjidakis, Cynthia Marie; Haiduc, Maria; Hamagaki, Hideki; Hamar, Gergoe; Harris, John William; Harton, Austin Vincent; Hatzifotiadou, Despina; Hayashi, Shinichi; Heckel, Stefan Thomas; Heide, Markus Ansgar; Helstrup, Haavard; Herghelegiu, Andrei Ionut; Herrera Corral, Gerardo Antonio; Hess, Benjamin Andreas; Hetland, Kristin Fanebust; Hilden, Timo Eero; Hillemanns, Hartmut; Hippolyte, Boris; Hosokawa, Ritsuya; Hristov, Peter Zahariev; Huang, Meidana; Humanic, Thomas; Hussain, Nur; Hussain, Tahir; Hutter, Dirk; Hwang, Dae Sung; Ilkaev, Radiy; Ilkiv, Iryna; Inaba, Motoi; Ippolitov, Mikhail; Irfan, Muhammad; Ivanov, Marian; Ivanov, Vladimir; Izucheev, Vladimir; Jacobs, Peter Martin; Jadhav, Manoj Bhanudas; Jadlovska, Slavka; Jahnke, Cristiane; Jang, Haeng Jin; Janik, Malgorzata Anna; Pahula Hewage, Sandun; Jena, Chitrasen; Jena, Satyajit; Jimenez Bustamante, Raul Tonatiuh; Jones, Peter Graham; Jung, Hyungtaik; Jusko, Anton; Kalinak, Peter; Kalweit, Alexander Philipp; Kamin, Jason Adrian; Kang, Ju Hwan; Kaplin, Vladimir; Kar, Somnath; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karayan, Lilit; Karpechev, Evgeny; Kebschull, Udo Wolfgang; Keidel, Ralf; Keijdener, Darius Laurens; Keil, Markus; Khan, Mohammed Mohisin; Khan, Palash; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Kileng, Bjarte; Kim, Beomkyu; Kim, Do Won; Kim, Dong Jo; Kim, Hyeonjoong; Kim, Jinsook; Kim, Mimae; Kim, Minwoo; Kim, Se Yong; Kim, Taesoo; Kirsch, Stefan; Kisel, Ivan; Kiselev, Sergey; Kisiel, Adam Ryszard; Kiss, Gabor; Klay, Jennifer Lynn; Klein, Carsten; Klein, Jochen; Klein-Boesing, Christian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Kobayashi, Taiyo; Kobdaj, Chinorat; Kofarago, Monika; Kollegger, Thorsten; Kolozhvari, Anatoly; Kondratev, Valerii; Kondratyeva, Natalia; Kondratyuk, Evgeny; Konevskikh, Artem; Kopcik, Michal; Kour, Mandeep; Kouzinopoulos, Charalampos; Kovalenko, Oleksandr; Kovalenko, Vladimir; Kowalski, Marek; Koyithatta Meethaleveedu, Greeshma; Kral, Jiri; Kralik, Ivan; Kravcakova, Adela; Kretz, Matthias; Krivda, Marian; Krizek, Filip; Kryshen, Evgeny; Krzewicki, Mikolaj; Kubera, Andrew Michael; Kucera, Vit; Kugathasan, Thanushan; Kuhn, Christian Claude; Kuijer, Paulus Gerardus; Kumar, Ajay; Kumar, Jitendra; Lokesh, Kumar; Kumar, Shyam; Kurashvili, Podist; Kurepin, Alexander; Kurepin, Alexey; Kuryakin, Alexey; Kushpil, Svetlana; Kweon, Min Jung; Kwon, Youngil; La Pointe, Sarah Louise; La Rocca, Paola; Lagana Fernandes, Caio; Lakomov, Igor; Langoy, Rune; Lara Martinez, Camilo Ernesto; Lardeux, Antoine Xavier; Lattuca, Alessandra; Laudi, Elisa; Lea, Ramona; Leardini, Lucia; Lee, Graham Richard; Lee, Seongjoo; Legrand, Iosif; Lehas, Fatiha; Lemmon, Roy Crawford; Lenti, Vito; Leogrande, Emilia; Leon Monzon, Ildefonso; Leoncino, Marco; Levai, Peter; Li, Shuang; Li, Xiaomei; Lien, Jorgen Andre; Lietava, Roman; Lindal, Svein; Lindenstruth, Volker; Lippmann, Christian; Lisa, Michael Annan; Ljunggren, Hans Martin; Lodato, Davide Francesco; Lonne, Per-Ivar; Loginov, Vitaly; Loizides, Constantinos; Lopez, Xavier Bernard; Lopez Torres, Ernesto; Lowe, Andrew John; Luettig, Philipp Johannes; Lunardon, Marcello; Luparello, Grazia; Ferreira Natal Da Luz, Pedro Hugo; Maevskaya, Alla; Mager, Magnus; Mahajan, Sanjay; Mahmood, Sohail Musa; Maire, Antonin; Majka, Richard Daniel; Malaev, Mikhail; Maldonado Cervantes, Ivonne Alicia; Malinina, Liudmila; Mal'Kevich, Dmitry; Malzacher, Peter; Mamonov, Alexander; Manko, Vladislav; Manso, Franck; Manzari, Vito; Marchisone, Massimiliano; Mares, Jiri; Margagliotti, Giacomo Vito; Margotti, Anselmo; Margutti, Jacopo; Marin, Ana Maria; Markert, Christina; Marquard, Marco; Martin, Nicole Alice; Martin Blanco, Javier; Martinengo, Paolo; Martinez Hernandez, Mario Ivan; Martinez-Garcia, Gines; Martinez Pedreira, Miguel; Martynov, Yevgen; Mas, Alexis Jean-Michel; Masciocchi, Silvia; Masera, Massimo; Masoni, Alberto; Massacrier, Laure Marie; Mastroserio, Annalisa; Masui, Hiroshi; Matyja, Adam Tomasz; Mayer, Christoph; Mazer, Joel Anthony; Mazzoni, Alessandra Maria; Mcdonald, Daniel; Meddi, Franco; Melikyan, Yuri; Menchaca-Rocha, Arturo Alejandro; Meninno, Elisa; Mercado-Perez, Jorge; Meres, Michal; Miake, Yasuo; Mieskolainen, Matti Mikael; Mikhaylov, Konstantin; Milano, Leonardo; Milosevic, Jovan; Minervini, Lazzaro Manlio; Mischke, Andre; Mishra, Aditya Nath; Miskowiec, Dariusz Czeslaw; Mitra, Jubin; Mitu, Ciprian Mihai; Mohammadi, Naghmeh; Mohanty, Bedangadas; Molnar, Levente; Montano Zetina, Luis Manuel; Montes Prado, Esther; Morando, Maurizio; Moreira De Godoy, Denise Aparecida; Perez Moreno, Luis Alberto; Moretto, Sandra; Morreale, Astrid; Morsch, Andreas; Muccifora, Valeria; Mudnic, Eugen; Muhlheim, Daniel Michael; Muhuri, Sanjib; Mukherjee, Maitreyee; Mulligan, James Declan; Gameiro Munhoz, Marcelo; Munzer, Robert Helmut; Murray, Sean; Musa, Luciano; Musinsky, Jan; Naik, Bharati; Nair, Rahul; Nandi, Basanta Kumar; Nania, Rosario; Nappi, Eugenio; Naru, Muhammad Umair; Nattrass, Christine; Nayak, Kishora; Nayak, Tapan Kumar; Nazarenko, Sergey; Nedosekin, Alexander; Nellen, Lukas; Ng, Fabian; Nicassio, Maria; Niculescu, Mihai; Niedziela, Jeremi; Nielsen, Borge Svane; Nikolaev, Sergey; Nikulin, Sergey; Nikulin, Vladimir; Noferini, Francesco; Nomokonov, Petr; Nooren, Gerardus; Cabanillas Noris, Juan Carlos; Norman, Jaime; Nyanin, Alexander; Nystrand, Joakim Ingemar; Oeschler, Helmut Oskar; Oh, Saehanseul; Oh, Sun Kun; Ohlson, Alice Elisabeth; Okatan, Ali; Okubo, Tsubasa; Olah, Laszlo; Oleniacz, Janusz; Oliveira Da Silva, Antonio Carlos; Oliver, Michael Henry; Onderwaater, Jacobus; Oppedisano, Chiara; Orava, Risto; Ortiz Velasquez, Antonio; Oskarsson, Anders Nils Erik; Otwinowski, Jacek Tomasz; Oyama, Ken; Ozdemir, Mahmut; Pachmayer, Yvonne Chiara; Pagano, Paola; Paic, Guy; Pajares Vales, Carlos; Pal, Susanta Kumar; Pan, Jinjin; Pandey, Ashutosh Kumar; Pant, Divyash; Papcun, Peter; Papikyan, Vardanush; Pappalardo, Giuseppe; Pareek, Pooja; Park, Woojin; Parmar, Sonia; Passfeld, Annika; Paticchio, Vincenzo; Patra, Rajendra Nath; Paul, Biswarup; Peitzmann, Thomas; Pereira Da Costa, Hugo Denis Antonio; Pereira De Oliveira Filho, Elienos; Peresunko, Dmitry Yurevich; Perez Lara, Carlos Eugenio; Perez Lezama, Edgar; Peskov, Vladimir; Pestov, Yury; Petracek, Vojtech; Petrov, Viacheslav; Petrovici, Mihai; Petta, Catia; Piano, Stefano; Pikna, Miroslav; Pillot, Philippe; Pinazza, Ombretta; Pinsky, Lawrence; Piyarathna, Danthasinghe; Ploskon, Mateusz Andrzej; Planinic, Mirko; Pluta, Jan Marian; Pochybova, Sona; Podesta Lerma, Pedro Luis Manuel; Poghosyan, Martin; Polishchuk, Boris; Poljak, Nikola; Poonsawat, Wanchaloem; Pop, Amalia; Porteboeuf, Sarah Julie; Porter, R Jefferson; Pospisil, Jan; Prasad, Sidharth Kumar; Preghenella, Roberto; Prino, Francesco; Pruneau, Claude Andre; Pshenichnov, Igor; Puccio, Maximiliano; Puddu, Giovanna; Pujahari, Prabhat Ranjan; Punin, Valery; Putschke, Jorn Henning; Qvigstad, Henrik; Rachevski, Alexandre; Raha, Sibaji; Rajput, Sonia; Rak, Jan; Rakotozafindrabe, Andry Malala; Ramello, Luciano; Rami, Fouad; Raniwala, Rashmi; Raniwala, Sudhir; Rasanen, Sami Sakari; Rascanu, Bogdan Theodor; Rathee, Deepika; Read, Kenneth Francis; Real, Jean-Sebastien; Redlich, Krzysztof; Reed, Rosi Jan; Rehman, Attiq Ur; Reichelt, Patrick Simon; Reidt, Felix; Ren, Xiaowen; Renfordt, Rainer Arno Ernst; Reolon, Anna Rita; Reshetin, Andrey; Rettig, Felix Vincenz; Revol, Jean-Pierre; Reygers, Klaus Johannes; Riabov, Viktor; Ricci, Renato Angelo; Richert, Tuva Ora Herenui; Richter, Matthias Rudolph; Riedler, Petra; Riegler, Werner; Riggi, Francesco; Ristea, Catalin-Lucian; Rivetti, Angelo; Rocco, Elena; Rodriguez Cahuantzi, Mario; Rodriguez Manso, Alis; Roeed, Ketil; Rogochaya, Elena; Rohr, David Michael; Roehrich, Dieter; Romita, Rosa; Ronchetti, Federico; Ronflette, Lucile; Rosnet, Philippe; Rossi, Andrea; Roukoutakis, Filimon; Roy, Ankhi; Roy, Christelle Sophie; Roy, Pradip Kumar; Rubio Montero, Antonio Juan; Rui, Rinaldo; Russo, Riccardo; Ryabinkin, Evgeny; Ryabov, Yury; Rybicki, Andrzej; Sadovskiy, Sergey; Safarik, Karel; Sahlmuller, Baldo; Sahoo, Pragati; Sahoo, Raghunath; Sahoo, Sarita; Sahu, Pradip Kumar; Saini, Jogender; Sakai, Shingo; Saleh, Mohammad Ahmad; Salgado Lopez, Carlos Alberto; Salzwedel, Jai Samuel Nielsen; Sambyal, Sanjeev Singh; Samsonov, Vladimir; Sandor, Ladislav; Sandoval, Andres; Sano, Masato; Sarkar, Debojit; Scapparone, Eugenio; Scarlassara, Fernando; Scharenberg, Rolf Paul; Schiaua, Claudiu Cornel; Schicker, Rainer Martin; Schmidt, Christian Joachim; Schmidt, Hans Rudolf; Schuchmann, Simone; Schukraft, Jurgen; Schulc, Martin; Schuster, Tim Robin; Schutz, Yves Roland; Schwarz, Kilian Eberhard; Schweda, Kai Oliver; Scioli, Gilda; Scomparin, Enrico; Scott, Rebecca Michelle; Seger, Janet Elizabeth; Sekiguchi, Yuko; Sekihata, Daiki; Selyuzhenkov, Ilya; Senosi, Kgotlaesele; Seo, Jeewon; Serradilla Rodriguez, Eulogio; Sevcenco, Adrian; Shabanov, Arseniy; Shabetai, Alexandre; Shadura, Oksana; Shahoyan, Ruben; Shangaraev, Artem; Sharma, Ankita; Sharma, Mona; Sharma, Monika; Sharma, Natasha; Shigaki, Kenta; Shtejer Diaz, Katherin; Sibiryak, Yury; Siddhanta, Sabyasachi; Sielewicz, Krzysztof Marek; Siemiarczuk, Teodor; Silvermyr, David Olle Rickard; Silvestre, Catherine Micaela; Simatovic, Goran; Simonetti, Giuseppe; Singaraju, Rama Narayana; Singh, Ranbir; Singha, Subhash; Singhal, Vikas; Sinha, Bikash; Sarkar - Sinha, Tinku; Sitar, Branislav; Sitta, Mario; Skaali, Bernhard; Slupecki, Maciej; Smirnov, Nikolai; Snellings, Raimond; Snellman, Tomas Wilhelm; Soegaard, Carsten; Soltz, Ron Ariel; Song, Jihye; Song, Myunggeun; Song, Zixuan; Soramel, Francesca; Sorensen, Soren Pontoppidan; Spacek, Michal; Spiriti, Eleuterio; Sputowska, Iwona Anna; Spyropoulou-Stassinaki, Martha; Srivastava, Brijesh Kumar; Stachel, Johanna; Stan, Ionel; Stefanek, Grzegorz; Stenlund, Evert Anders; Steyn, Gideon Francois; Stiller, Johannes Hendrik; Stocco, Diego; Strmen, Peter; Alarcon Do Passo Suaide, Alexandre; Sugitate, Toru; Suire, Christophe Pierre; Suleymanov, Mais Kazim Oglu; Suljic, Miljenko; Sultanov, Rishat; Sumbera, Michal; Symons, Timothy; Szabo, Alexander; Szanto De Toledo, Alejandro; Szarka, Imrich; Szczepankiewicz, Adam; Szymanski, Maciej Pawel; Tabassam, Uzma; Takahashi, Jun; Tambave, Ganesh Jagannath; Tanaka, Naoto; Tangaro, Marco-Antonio; Tapia Takaki, Daniel Jesus; Tarantola Peloni, Attilio; Tarhini, Mohamad; Tariq, Mohammad; Tarzila, Madalina-Gabriela; Tauro, Arturo; Tejeda Munoz, Guillermo; Telesca, Adriana; Terasaki, Kohei; Terrevoli, Cristina; Teyssier, Boris; Thaeder, Jochen Mathias; Thomas, Deepa; Tieulent, Raphael Noel; Timmins, Anthony Robert; Toia, Alberica; Trogolo, Stefano; Trubnikov, Victor; Trzaska, Wladyslaw Henryk; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ullaland, Kjetil; Uras, Antonio; Usai, Gianluca; Utrobicic, Antonija; Vajzer, Michal; Valencia Palomo, Lizardo; Vallero, Sara; Van Der Maarel, Jasper; Van Hoorne, Jacobus Willem; Van Leeuwen, Marco; Vanat, Tomas; Vande Vyvre, Pierre; Varga, Dezso; Vargas Trevino, Aurora Diozcora; Vargyas, Marton; Varma, Raghava; Vasileiou, Maria; Vasiliev, Andrey; Vauthier, Astrid; Vechernin, Vladimir; Veen, Annelies Marianne; Veldhoen, Misha; Velure, Arild; Venaruzzo, Massimo; Vercellin, Ermanno; Vergara Limon, Sergio; Vernet, Renaud; Verweij, Marta; Vickovic, Linda; Viesti, Giuseppe; Viinikainen, Jussi Samuli; Vilakazi, Zabulon; Villalobos Baillie, Orlando; Villatoro Tello, Abraham; Vinogradov, Alexander; Vinogradov, Leonid; Vinogradov, Yury; Virgili, Tiziano; Vislavicius, Vytautas; Viyogi, Yogendra; Vodopyanov, Alexander; Volkl, Martin Andreas; Voloshin, Kirill; Voloshin, Sergey; Volpe, Giacomo; Von Haller, Barthelemy; Vorobyev, Ivan; Vranic, Danilo; Vrlakova, Janka; Vulpescu, Bogdan; Vyushin, Alexey; Wagner, Boris; Wagner, Jan; Wang, Hongkai; Wang, Mengliang; Watanabe, Daisuke; Watanabe, Yosuke; Weber, Michael; Weber, Steffen Georg; Wessels, Johannes Peter; Westerhoff, Uwe; Wiechula, Jens; Wikne, Jon; Wilde, Martin Rudolf; Wilk, Grzegorz Andrzej; Wilkinson, Jeremy John; Williams, Crispin; Windelband, Bernd Stefan; Winn, Michael Andreas; Yaldo, Chris G; Yang, Hongyan; Yang, Ping; Yano, Satoshi; Yasar, Cigdem; Yin, Zhongbao; Yokoyama, Hiroki; Yoo, In-Kwon; Yurchenko, Volodymyr; Yushmanov, Igor; Zaborowska, Anna; Zaccolo, Valentina; Zaman, Ali; Zampolli, Chiara; Correia Zanoli, Henrique Jose; Zaporozhets, Sergey; Zardoshti, Nima; Zarochentsev, Andrey; Zavada, Petr; Zavyalov, Nikolay; Zbroszczyk, Hanna Paulina; Zgura, Sorin Ion; Zhalov, Mikhail; Zhang, Haitao; Zhang, Xiaoming; Zhang, Yonghong; Zhang, Zuman; Zhao, Chengxin; Zhigareva, Natalia; Zhou, Daicui; Zhou, You; Zhou, Zhuo; Zhu, Hongsheng; Zhu, Jianhui; Zichichi, Antonino; Zimmermann, Alice; Zimmermann, Markus Bernhard; Zinovjev, Gennady; Zyzak, Maksym

    2016-01-01

    ALICE is one of four large experiments at the CERN Large Hadron Collider near Geneva, specially designed to study particle production in ultra-relativistic heavy-ion collisions. Located 52 meters underground with 28 meters of overburden rock, it has also been used to detect muons produced by cosmic ray interactions in the upper atmosphere. In this paper, we present the multiplicity distribution of these atmospheric muons and its comparison with Monte Carlo simulations. This analysis exploits the large size and excellent tracking capability of the ALICE Time Projection Chamber. A special emphasis is given to the study of high multiplicity events containing more than 100 reconstructed muons and corresponding to a muon areal density $\\rho_{\\mu} > 5.9~$m$^{-2}$. Similar events have been studied in previous underground experiments such as ALEPH and DELPHI at LEP. While these experiments were able to reproduce the measured muon multiplicity distribution with Monte Carlo simulations at low and intermediate multiplic...

  11. American superconductor technology to help CERN to explore the mysteries of matter company's high temperature superconductor wire to be used in CERN's Large Hadron Collider

    CERN Multimedia

    2003-01-01

    American Superconductor Corporation has been selected by CERN, to provide 14,000 meters of high temperature superconductor (HTS) wire for current lead devices that will be used in CERN's Large Hadron Collider (1 page).

  12. Hangout With CERN: The Large Hadron Collider (S01E02)

    CERN Multimedia

    Kahle, Kate

    2012-01-01

    In this second Hangout with CERN "The Large Hadron Collider" ATLAS physicist Steven Goldfarb is joined by Giulia Papotti and Laurette Ponce from the CERN Control Centre, Despina Hatzifotiadou and Ken Read from the ALICE experiment, Achintya Rao and Roberto Rossin from the CMS experiment and Patrick Koppenburg from the LHCb experiment, as well as Jaana Nystrom from Finland and Liz Krane from the USA. This hangout answers questions about the Large Hadron Collider (LHC) received via #askCERN on Twitter and Google+ and via YouTube and Facebook comments. Recorded live on 8th November 2012.

  13. CERN-Fermilab Hadron Collider Physics Summer School 2013 open for applications

    CERN Multimedia

    2013-01-01

    Mark your calendar for 28 August - 6 September 2013, when CERN will welcome students to the eighth CERN-Fermilab Hadron Collider Physics Summer School.   Experiments at hadron colliders will continue to provide our best tools for exploring physics at the TeV scale for some time. With the completion of the 7-8 TeV runs of the LHC, and the final results from the full Tevatron data sample becoming available, a new era in particle physics is beginning, heralded by the Higgs-like particle recently discovered at 125 GeV. To realize the full potential of these developments, CERN and Fermilab are jointly offering a series of "Hadron Collider Physics Summer Schools", to prepare young researchers for these exciting times. The school has alternated between CERN and Fermilab, and will return to CERN for the eighth edition, from 28 August to 6 September 2013. The CERN-Fermilab Hadron Collider Physics Summer School is an advanced school which particularly targets young postdocs in exper...

  14. Investigation of induced radioactivity in the CERN Large Electron Positron collider for its decommissioning

    CERN Document Server

    Silari, Marco

    2004-01-01

    The future installation of the Large Hadron Collider in the tunnel formerly housing the Large Electron Positron collider (LEP) required the dismantling of the latter after 11-year operation. As required by the French legislation, an extensive theoretical study was conducted before decommissioning to establish the possible activation paths both in the accelerator and in the four experiments (L3, ALEPH, OPAL and DELPHI) installed around the ring. The aim was to define which areas may contain activated material and which ones would be completely free of activation. The four major sources of activation in LEP, i.e., distributed and localized beam losses, synchrotron radiation and the super-conducting RF cavities, were investigated. Conversion coefficients from unit lost beam power to induced specific activity were established for a number of materials. A similar study was conducted for the four experiments, evaluating the four potential sources of induced radioactivity, namely e**+e **- annihilation events, two-p...

  15. LEP is upgraded

    CERN Multimedia

    1995-01-01

    A superconducting radio-frequency cavity is installed on the Large Electron-Positron (LEP) collider. This upgrade, known as LEP-2, allowed the accelerator to reach new, higher energies and so investigate new areas of physics.

  16. The future of the Large Hadron Collider and CERN.

    Science.gov (United States)

    Heuer, Rolf-Dieter

    2012-02-28

    This paper presents the Large Hadron Collider (LHC) and its current scientific programme and outlines options for high-energy colliders at the energy frontier for the years to come. The immediate plans include the exploitation of the LHC at its design luminosity and energy, as well as upgrades to the LHC and its injectors. This may be followed by a linear electron-positron collider, based on the technology being developed by the Compact Linear Collider and the International Linear Collider collaborations, or by a high-energy electron-proton machine. This contribution describes the past, present and future directions, all of which have a unique value to add to experimental particle physics, and concludes by outlining key messages for the way forward.

  17. Timken steel technology used in CERN's hadron collider

    CERN Multimedia

    2007-01-01

    "The Timken Company's steel technology helped Superbolt, Inc. provide equipment to the European Organization for Nuclear Research (CERN) and its large particle physics laboratory located near Geneva, Switzerland." (1,5 page)

  18. CERN told to start technical thinking for next collider

    CERN Multimedia

    1998-01-01

    CERN has been told to begin technical design work for the successor to the LHC. A report commissioned last year, suggests that future design work should focus on developping cost-effective high-field magnets (1 page).

  19. Measurement of the s dependence of jet production at the CERN pp collider

    DEFF Research Database (Denmark)

    Appel, J.A.; Bagnaia, P.; Banner, M.;

    1985-01-01

    The production of very large transverse momentum (pT) hadron jets has been measured in the UA2 experiment at the CERN pp Collider for s=630 GeV. The inclusive jet production cross sections exhibit a pT-dependent increase with respect to the s=546 GeV data from previous Collider runs. This increas...... of preons in the quark (Λc>370 GeV at 95% CL)....

  20. LEP3: A high luminosity e+e- collider in the LHC tunnel to study the Higgs boson

    CERN Document Server

    Blondel, A P; Koratzinos, M; Zanetti, M

    2012-01-01

    Recent indications from the LHC suggest that the Higgs boson might be light, within the mass range 115- 130 GeV. Such object could be studied at an e+e− collider with about 240-GeV centre-of-mass energy. A corresponding Higgs factory – ‘LEP3’ – could be installed in the LHC tunnel, reducing its cost and also allowing for a second life of the two LHC general-purpose detectors. We present preliminary accelerator and beam parameters for LEP3 [1] tailored so as to provide a peak luminosity of 1034 cm-2s-1 at each of two experiments, while respecting a number of constraints including beamstrahlung limits. At this luminosity around 20,000 Higgs events per year per experiment could be obtained for a Standard Model Higgs boson with a mass of 115-130 GeV. For the parameters considered the estimated luminosity lifetime is about 16 minutes, and the synchrotron radiation losses are 50 MW per beam. High operational efficiency requires two rings: a low emittance collider storage ring operating at constant energy,...

  1. Public Lecture Collide@CERN Pro Helvetia | 23 July | Main Auditorium

    CERN Multimedia

    2015-01-01

    You are very warmly invited to the opening presentation of Fragment.In’s residency at CERN.   Fragment.In: Simon de Diesbach, Laura Perrenoud and Marc Dubois. 23 July 2015 - 7 p.m. Main Auditorium  The lecture will be followed by a drinks reception at 8.30 p.m. Doors open at 6.30 p.m.  Opening address by Rolf Heuer, CERN Director-General, Michel Vust, project leader at the Swiss Arts Council Pro Helvetia, and Monica Bello, Head of Arts@CERN. Fragment.In are the winners of Collide@CERN Pro Helvetia, formed by Laura Perrenoud, Simon de Diesbach, and Marc Dubois. They will present their artistic work along with their CERN scientific inspiration partner, who will present his/her scientific work. In their proposal, Fragment.In took a unique, original and creative approach to data visualization. We look forward to having them at CERN.  Fragment.In Collide@CERN is the three month residency programme providing artists with time and...

  2. High Energy Booster Options for a Future Circular Collider at CERN

    CERN Document Server

    Stoel, Linda; Bartmann, Wolfgang; Burkart, Florian; Goddard, Brennan; Herr, Werner; Kramer, Thomas; Milanese, Attilio; Rumolo, Giovanni; Shaposhnikova, Elena

    2016-01-01

    In case a Future Circular Collider for hadrons (FCC-hh) is constructed at CERN, the tunnels for SPS, LHC and the 100 km collider will be available to house a High Energy Booster (HEB). The different machine options cover a large technology range from an iron-dominated machine in the 100 km tunnel to a superconducting machine in the SPS tunnel. Using a modified LHC as reference, these options are compared with respect to their energy reach, magnet technology and filling time of the collider. Potential issues with beam transfer, reliability and beam stability are presented.

  3. 1986 CERN school of physics

    International Nuclear Information System (INIS)

    The CERN school of physics is intended to give young experimental physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These proceedings contain reports of lecture series on the following topics: introduction to symmetries and gauge theories, quark dynamics, experimental tests of gauge theories, proton antiproton collider results and detectors, physics at LEP, superphysics, and quantum black holes. (orig.)

  4. CERN celebrating the Lowering of the final detector element for large Hadron Collider

    CERN Multimedia

    2008-01-01

    In the early hours of the morning the final element of the Compact Muon Solenoid (CMS) detector began the descent into its underground experimental cavern in preparation for the start-up of CERNs Large Hadron Collider (LHC) this summer. This is a pivotal moment for the CMS collaboration.

  5. A search for relativistic particles with fractional electric charge at the Cern collider

    DEFF Research Database (Denmark)

    Banner, M.; Kofoed-Hansen, O.

    1983-01-01

    A search for relativistic particles with fractional electric charge has been performed at the CERN collider using a telescope of scintillation counters to detect particles with abnormally low ionisation. The thickness of the detector (40 gr cm−2) limits this search to particles without strong...

  6. Taking Energy to the Physics Classroom from the Large Hadron Collider at CERN

    Science.gov (United States)

    Cid, Xabier; Cid, Ramon

    2009-01-01

    In 2008, the greatest experiment in history began. When in full operation, the Large Hadron Collider (LHC) at CERN will generate the greatest amount of information that has ever been produced in an experiment before. It will also reveal some of the most fundamental secrets of nature. Despite the enormous amount of information available on this…

  7. Measurement of jet fragmentation properties at the CERN anti pp collider

    International Nuclear Information System (INIS)

    Fragmentation properties of a sample of two-jet events measured by the UA2 detector at the CERN anti pp Collider are described. The energy flow is compared with different model predictions. The charged particle multiplicity in jets is found to exceed extrapolations from lower energy e+e- jet data. (orig.)

  8. There’s more to particle physics at CERN than colliders

    CERN Multimedia

    2016-01-01

    CERN’s scientific programme must be compelling, unique, diverse, and integrated into the global landscape of particle physics. One of the Laboratory’s primary goals is to provide a diverse range of excellent physics opportunities and to put its unique facilities to optimum use, maximising the scientific return.   In this spirit, we have recently established a Physics Beyond Colliders study group with a mandate to explore the unique opportunities offered by the CERN accelerator complex to address some of today’s outstanding questions in particle physics through projects complementary to high-energy colliders and other initiatives in the world. The study group will provide input to the next update of the European Strategy for Particle Physics. The process kicked off with a two-day workshop at CERN on 6 and 7 September, organised by the study group conveners: Joerg Jaeckel (Heidelberg), Mike Lamont (CERN) and Claude Vallée (CPPM Marseille and DESY). Its purpo...

  9. Inclusive Charged Particle Production at the CERN pp Collider

    DEFF Research Database (Denmark)

    Banner, M.; Kofoed-Hansen, O.

    1983-01-01

    Transverse momentum distributions of pions, kaons and protons have been measured around 90° in the UA2 detector at the SPS p collider, at a CM energy of 540 GeV. All the cross sections have increased by more than a factor of 2 over those measured at ISR energies and exhibit a flatter behaviour wi...

  10. PARTICLE PHYSICS: CERN Collider Glimpses Supersymmetry--Maybe.

    Science.gov (United States)

    Seife, C

    2000-07-14

    Last week, particle physicists at the CERN laboratory in Switzerland announced that by smashing together matter and antimatter in four experiments, they detected an unexpected effect in the sprays of particles that ensued. The anomaly is subtle, and physicists caution that it might still be a statistical fluke. If confirmed, however, it could mark the long-sought discovery of a whole zoo of new particles--and the end of a long-standing model of particle physics.

  11. Une énergie record ouvre de nouvelles perspectives de découvertes au LEP

    CERN Multimedia

    CERN Press Office. Geneva

    1999-01-01

    At CERN on 2 August 1999 at 11h15, beams of electrons and positrons were accelerated in the Large Electron Positron Collider (LEP) to 100 GeV and brought into collision for the first time at this energy. There were two reasons for the backslapping, cheering and popping of corks that followed in the LEP control room. First, the setting of a new energy record for an electron-positron accelerator, represents a tremendous technical achievement by CERN accelerator specialists. Second, the collision energy of 200 GeV opens up exciting new discovery potential for the LEP experiments.

  12. Dimuon production at the CERN panti p collider

    International Nuclear Information System (INIS)

    In panti p collisions at 630 (540) GeV centre of mass energy heavy quarks are copiously produced, mainly by gluon fusion. About 10% of them decay semileptonically into muons. In order to study heavy quark physics at the collider, we selected dimuon event satisfying following cuts: Pt > 3 GeV/c (each muon) mμμ > 6 GeV/c2. (orig./HSI)

  13. A Large Hadron Electron Collider at CERN, Physics, Machine, Detector

    CERN Document Server

    Adolphson, C

    2011-01-01

    The physics programme and the design are described of a new electron-hadron collider, the LHeC, in which electrons of $60$ to possibly $140$\\,GeV collide with LHC protons of $7000$\\,GeV. With an $ep$ design luminosity of about $10^{33}$\\,cm$^{-2}$s$^{-1}$, the Large Hadron Electron Collider exceeds the integrated luminosity collected at HERA by two orders of magnitude and the kinematic range by a factor of twenty in the four-momentum squared, $Q^2$, and in the inverse Bjorken $x$. The physics programme is devoted to an exploration of the energy frontier, complementing the LHC and its discovery potential for physics beyond the Standard Model with high precision deep inelastic scattering (DIS) measurements. These are projected to solve a variety of fundamental questions in strong and electroweak interactions. The LHeC thus becomes the world's cleanest high resolution microscope, designed to continue the path of deep inelastic lepton-hadron scattering into unknown areas of physics and kinematics. The physics ...

  14. CERN-BINP Workshop for Young Scientists in e+e- Colliders

    CERN Document Server

    2016-01-01

    The "CERN-BINP workshop for young scientists in e+e- colliders" is organised in the framework of the EU-funded CREMLIN project. The CREMLIN project aims at strengthening science cooperation between six Russian megascience facilities and related research infrastructure counterparts in Europe. BINP and CERN coordinate a dedicated CREMLIN work package focusing on a future super-charm-tau factory (SCT) at BINP. SCT aims at producing e+e- collisions with up to 5 GeV centre-of-mass energy and at very high luminosity. In parallel CERN is hosting design studies for two possible high-energy e+e- colliders: FCC-ee and CLIC. In matters of physics, design and technologies the BINP and CERN studies address technological and scientific questions of common interest. Similar issues are dealt with in the framework of other flavour factories and energy frontier e+e- colliders worldwide. The 3-day workshop provides young scientists (at the student and postdoc level) opportunities to present their work and exchange experiences. ...

  15. Testing Color Evaporation in Photon-Photon Production of $J/\\Psi$ at CERN LEP II

    CERN Document Server

    Éboli, Oscar J P; Mizukoshi, J K

    2003-01-01

    The DELPHI Collaboration has recently reported the measurement of J/Psi production in photon-photon collisions at LEP II. These newly available data provide an additional proof of the importance of colored c bar{c} pairs for the production of charmonium because these data can only be explained by considering resolved photon processes. We show here that the inclusion of color octet contributions to the J/Psi production in the framework of the color evaporation model is able to reproduce this data. In particular, the transverse-momentum distribution of the J/Psi mesons is well described by this model.

  16. A great european project: the electron-poistron collider ring (LEP). A window on the past; Un grande progetto europeo: l`anello di collisione elettrone-positrone (il LEP). Una finestra sul passato

    Energy Technology Data Exchange (ETDEWEB)

    Picasso, E.

    1996-12-31

    Cosmology is a historical discipline and as History, the farther away from the present the period studied, the fewer are the documents and their interpretation is ever more difficult. The Large electron positron Collider (LEP) enables the physicists to go back in time and to study the phenomena which occurred approximately one tenth of a thousandth millionth of a second after the Big Bang. In the Avogadro`s conference the cosmological arguments are briefly presented and LEP is described in some details. [Italiano] la Cosmologia e` una disciplina storica e come avviene per la storia piu` si allontana dalla nostra epoca il periodo da studiare, piu` rari si fanno i documenti e piu` difficile e` l`interpretazione. Il grande anello di collisione, il LEP, permette ai fisici di risalire indietro nel tempo e di studiare i fenomeni che sono avvenuti circa un decimo di miliardesimo dopo il Big Bang. In questo senso limitato il LEP e` una finestra sul tempo. Nella conferenza Avogadro gli argomenti di cosmologia sono brevemente presentati e la costruzione del LEP e` descritta in dettaglio.

  17. Collide@CERN: exclusive open rehearsal of Gilles Jobin's last piece

    CERN Multimedia

    2012-01-01

    Collide@CERN and Gilles Jobin, artist in residency at CERN, present an exclusive open rehearsal of his last piece SPIDER GALAXIES Tuesday 31 July 2012 - A new piece created to open new territories of the mind - Join us in Restaurant 1 from 4 p.m. (next to the Glass Box Restaurant) With this piece, the body turns into matter, which is complete, spatial and sensual. Come and see Gilles Jobin and his dancers. With a score by Cristian Vogel and Carla Scaletti invoking sound particles, while Daniel Demont disperses the spectrum. Protean, infinitely large or infinitesimal, such are the Spider Galaxies.    

  18. Design and Installation Challenges of the Neutral Beam Absorbers for the Large Hadron Collider at CERN

    OpenAIRE

    Fernández Vélez, Óscar

    2005-01-01

    El CERN (Consejo Europeo de Investigación Nuclear) está construyendo su nuevo acelerador de partículas en la frontera franco-suiza. Actualmente en la fase de instalación, El Large Hadron Collider (LHC), con 26,7 kilómetros de longitud a 100 metros bajo tierra, será el mayor y más potente acelerador de partículas jamás construido. A su llegada al CERN, cada uno de casi 2000 imanes superconductores que formarán parte del acelerador debe ser verificado, ensamblado y transportado hasta ...

  19. Inside CERN's Large Hadron Collider from the proton to the Higgs boson

    CERN Document Server

    Campanelli, Mario

    2016-01-01

    The book aims to explain the historical development of particle physics, with special emphasis on CERN and collider physics. It describes in detail the LHC accelerator and its detectors, describing the science involved as well as the sociology of big collaborations, culminating with the discovery of the Higgs boson. Readers are led step-by-step to understanding why we do particle physics, as well as the tools and problems involved in the field. It provides an insider's view on the experiments at the Large Hadron Collider.

  20. The Atlas detector: a general purpose experiment at the large hadron collider at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Schwindling, J. [CEA Saclay, 91 - Gif-sur-Yvette (France). Dept. d' Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l' Instrumentation Associee

    1996-07-01

    The ATLAS collaboration has designed a general purpose detector to be operated at the Large Hadron Collider (LHC) at CERN. The design of the detector took into account the requirements from the physics and the constraints form the collider, but also the cost and technological aspects. It is supported by a large amount of detailed simulations and test activities. The following sections describe the various sub-detectors, starting from the inner tracker detectors which surround the interaction point, going through the electromagnetic (EM) and hadronic (HAD) calorimeters, and ending up with the external muon spectrometer and a few characteristics of the trigger system. (author)

  1. University of Tennessee deploys force10 C-series to analyze data from CERN's Large Hadron Collider

    CERN Multimedia

    2007-01-01

    "Force20 networks, the pioneer in building and securing reliable networks, today announced that the University of Tennessee physics department has deployed the C300 resilient switch to analyze data form CERN's Large Hadron Collider." (1 page)

  2. Diffractive Higgs boson production at the Fermilab Tevatron and the CERN Large Hadron Collider.

    Science.gov (United States)

    Enberg, R; Ingelman, G; Kissavos, A; Tîmneanu, N

    2002-08-19

    Improved possibilities to find the Higgs boson in diffractive events, having less hadronic activity, depend on whether the cross section is large enough. Based on the soft color interaction models that successfully describe diffractive hard scattering at DESY HERA and the Fermilab Tevatron, we find that only a few diffractive Higgs events may be produced at the Tevatron, but we predict a substantial rate at the CERN Large Hadron Collider.

  3. Determining the structure of Higgs couplings at the CERN LargeHadron Collider.

    Science.gov (United States)

    Plehn, Tilman; Rainwater, David; Zeppenfeld, Dieter

    2002-02-01

    Higgs boson production via weak boson fusion at the CERN Large Hadron Collider has the capability to determine the dominant CP nature of a Higgs boson, via the tensor structure of its coupling to weak bosons. This information is contained in the azimuthal angle distribution of the two outgoing forward tagging jets. The technique is independent of both the Higgs boson mass and the observed decay channel.

  4. Measurement of jet production properties at the CERN anti pp collider

    International Nuclear Information System (INIS)

    Jet production properties at √s=540 GeV have been measured in the UA2 detector at the CERN anti pp Collider. Results on the total transverse momentum of the jet system, on the parton density in the nucleon (structure function) and on the two-jet angular distributions are reported. The data are compared with QCD predictions and extrapolations from lower energy experiments. (orig.)

  5. Bosons production $W^{\\pm}$ via $e^{-}$ p-collisions at CERN LEP/LHC energies with a $W{\\pm}$ anomalous magnetic moment

    CERN Document Server

    Gutiérrez-Rodríguez, A

    2002-01-01

    We discuss the production of charged bosons in deep inelastic e/sup - /p-scattering, in the context of an electroweak model, in which the vector boson self interactions may be different from those prescribed by the electroweak standard model. We show that even small deviations from the standard model value of kappa ( kappa =1) implies an observable deviation in the W/sup +or-/ production rates at CERN LEP /LHC energies.

  6. News from the Library: CERN Library and Collide@CERN present media artist Nataša Teofilović

    CERN Multimedia

    CERN Library

    2012-01-01

    The Serbian media artist Nataša Teofilović creates virtual characters which are living art works, often employing animation techniques. She won an honorary mention for her work in the first Prix Ars Electronica Collide@CERN competition for her outstanding digital works which cross the boundaries between virtual and real spaces.  As part of her prize, Arts@CERN offered Nataša the opportunity for a two-day visit to CERN, which is being funded by a Swedish foundation travel grant.   Nataša talks about why and how she creates her digital work and virtual beings, shows examples and reveals insights into the role and status of an artist in her native Serbia. Nataša Teofilović has an PhD and MA in Digital Art (Belgrade University of Arts, Interdisciplinary Studies) and holds a BA in Architecture from Belgrade University of Architecture. She lives in Pančevo, Vojvodina, Serbia. See examples of Nataša’s work here. &quo...

  7. The LHCf detector at the CERN Large Hadron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Adriani, O; Bonechi, L; D' Alessandro, R [Universita degli Studi di Firenze and INFN Sezione di Firenze, Firenze (Italy); Bongi, M; Grandi, M; Papini, P [INFN Sezione di Firenze, Firenze (Italy); Castellini, G [IFAC CNR and INFN Sezione di Firenze, Firenze (Italy); Faus, D A [IFIC, Centro Mixto CSIC-UVEG, Valencia (Spain); Fukui, K; Itow, Y; Mase, T; Masuda, K; Matsubara, Y; Menjo, H [Solar-Terrestrial Environment laboratory, Nagoya University, Nagoya (Japan); Haguenauer, M [Ecole-Polytechnique, Paris (France); Kasahara, K; Mizuishi, M [Research Institute for Science and Engineering, Waseda University, Tokyo (Japan); Macina, D; Perrot, A L [CERN, Geneva (Switzerland); Muraki, Y [Konan University, Kobe (Japan)], E-mail: Daniela.Macina@cern.ch (and others)

    2008-08-15

    LHCf is an experiment dedicated to the measurement of neutral particles emitted in the very forward region of LHC collisions. The physics goal is to provide data for calibrating the hadron interaction models that are used in the study of Extremely High-Energy Cosmic-Rays. This is possible since the laboratory equivalent collision energy of LHC is 10{sup 17} eV. Two LHCf detectors, consisting of imaging calorimeters made of tungsten plates, plastic scintillator and position sensitive sensors, are installed at zero degree collision angle {+-}140 m from an interaction point (IP). Although the lateral dimensions of these calorimeters are very compact, ranging from 20 mm x 20 mm to 40 mm x 40 mm, the energy resolution is expected to be better than 6% and the position resolution better than 0.2 mm for {gamma}-rays with energy from 100 GeV to 7 TeV. This has been confirmed by test beam results at the CERN SPS. These calorimeters can measure particles emitted in the pseudo rapidity range {eta} > 8.4. Detectors, data acquisition and electronics are optimized to operate during the early phase of the LHC commissioning with luminosity below 10{sup 30} cm{sup -2} s{sup -1}. LHCf is expected to obtain data to compare with the major hadron interaction models within a week or so of operation at luminosity {approx} 10{sup 29} cm{sup -2} s{sup -1}. After {approx} 10 days of operation at luminosity {approx} 10{sup 29} cm{sup -2} s{sup -1}, the light output of the plastic scintillators is expected to degrade by {approx} 10% due to radiation damage. This degradation will be monitored and corrected for using calibration pulses from a laser.

  8. Tau physics at LEP

    International Nuclear Information System (INIS)

    This articles reviews major results on τ physics derived from the analysis of τ+τ- final states produced at the e+e- collider LEP at CERN. Results are summarized for the physics of the neutral weak current in τ-pair production as well as of the charged weak current in τ decays. Results on the neutral current include measurements of total cross sections and of forward-backward, polarization and forward-backward polarization asymmetries. Results on the charged current include measurements of the τ lifetime, inclusive as well as exclusive branching fractions and Michel parameters. Also discussed are the determination of the strong coupling constant, limits on the mass of the τ neutrino, and τ physics beyond the Minimal Standard Model. (orig.)

  9. A Common Software Configuration Management System for CERN SPS and LEP Accelerators and Technical Services

    CERN Document Server

    Hatziangeli, Eugenia; Bragg, A E; Ninin, P; Patino, J; Sobczak, H

    1999-01-01

    Software configuration management activities are crucial to assure the integrity of current operational and the quality of new software either being developed at CERN or outsourced. The functionality of the present management system became insufficient with large maintenance overheads. In order to improve our situation, a new software configuration management system has been set up. It is based on Razor, a commercial tool, which supports the management of file versions and operational software releases, along with integrated problem reporting capabilities. In addition to the basic tool functionality, automated procedures were custom made, for the installation and distribution of operational software. Policies were developed and applied over the software development life cycle to provide visibility and control. The system ensures that, at all times, the status and location of all deliverable versions are known, the state of shared objects is carefully controlled and unauthorised changes prevented. It provides ...

  10. A Common Software-Configuration Management System for CERN SPS and LEP Accelerators and Technical Services

    CERN Document Server

    Hatziangeli, Eugenia; Bragg, A E; Ninin, P; Patino, J; Sobczak, H

    2000-01-01

    Software-configuration management activities are crucial to ensure the integrity of current operational software and the quality of new software either being developed at CERN or outsourced. The functionality of the present management system became insufficient with large maintenance overheads. In order to improve our situation, a new software-configuration management system has been set up. It is based on Razor R, a commercial tool, which supports the management of file versions and operational software releases, along with integrated problem-reporting capabilities. In addition to the basic tool functionality, automated procedures were custom-made for the installation and distribution of operational software. The system ensures that, at all times, the status and location of all deliverable versions are known, the state of shared objects is carefully controlled and unauthorized changes prevented. This paper outlines the reasons for selecting the chosen tool, the implementation of the system and the final goal...

  11. 3rd CERN-Fermilab HadronCollider Physics Summer School

    CERN Multimedia

    EP Department

    2008-01-01

    August 12-22, 2008, Fermilab The school web site is http://cern.ch/hcpss with links to the academic programme and the application procedure. The APPLICATION DEADLINE IS 29 FEBRUARY 2008. The goal of the CERN-Fermilab Hadron Collider Physics Summer Schools is to offer students and young researchers in high-energy physics a concentrated syllabus on the theory and experimental challenges of hadron collider physics. The third session of the summer school will focus on exposing young post-docs and advanced graduate students to broader theories and real data beyond what they’ve learned at their home institutions. Experts from across the globe will lecture on the theoretical and experimental foundations of hadron collider physics, host parallel discussion sessions and answer students’ questions. This year’s school will also have a greater focus on physics beyond the Standard Model, as well as more time for questions at the end of each lecture. The 2008 School will be held at Fermilab. Further enquiries should ...

  12. For Information: CERN-Fermilab2006 Hadron Collider Physics Summer School

    CERN Multimedia

    2006-01-01

    Applications are Now Open for the CERN-Fermilab2006 Hadron Collider Physics Summer School August 9-18, 2006 Please go to the school web site http://hcpss.fnal.gov/ and follow the links to the Application process. The APPLICATION DEADLINE IS APRIL 8, 2006. Successful applicants and support awards will be announced shortly thereafter. Also available on the web is the tentative academic program of the school. The main goal of the CERN-Fermilab Hadron Collider Physics Summer Schools is to offer students and young researchers a broad picture of both the theoretical and experimental aspects of hadron collider physics. The emphasis of the first school will be on the physics potential of the first years of data taking at the LHC, and on the experimental and theoretical tools needed to exploit that potential. A series of lectures and informal discussions will include an introduction to the theoretical and phenomenological framework of hadron collisions, and current theoretical models of frontier physics, as...

  13. Role-Based Access Control for the Large Hadron Collider at CERN

    CERN Document Server

    Yastrebov, I

    2010-01-01

    Large Hadron Collider (LHC) is the largest scientific instrument ever created. It was built with the intention of testing the most extreme conditions of the matter. Taking into account the significant dangers of LHC operations, European Organization for Nuclear Research (CERN) has developed multi-pronged approach for machine safety, including access control system. This system is based on role-based access control (RBAC) concept. It was designed to protect from accidental and unauthorized access to the LHC and injector equipment. This paper introduces the new model of the role-based access control developed at CERN and gives detailed mathematical description of it. We propose a new technique called dynamic authorization that allows deploying RBAC gradually in the large systems. Moreover, we show how the protection for the very large distributed equipment control system may be implemented in efficient way. This paper also describes motivation of the project, requirements and overview of the main components: au...

  14. Donation of LEP Equipment

    CERN Document Server

    2005-01-01

    In accordance with CERN's Financial Rules, the Management hereby notifies Finance Committee of the gift of a LEP copper cavity to the town of Meyrin (CH) following a request from the Meyrin municipal authorities.

  15. Histoire du LEP

    CERN Multimedia

    CERN Press Office. Geneva

    2000-01-01

    The LEP story begins in the late 1970s when CERN Member State physicists got together to discuss the long term future of high energy physics in Europe. A new picture of fundamental interactions, unifying the electromagnetic and weak forces, was emerging, and LEP would be the machine to study it.

  16. Pair production of neutral Higgs bosons at the CERN Large Hadron Collider

    CERN Document Server

    Barrientos-Bendezu, A A

    2001-01-01

    We study the hadroproduction of two neutral Higgs bosons in the minimal supersymmetric extension of the standard model, which provides a handle on the trilinear Higgs couplings. We include the contributions from quark-antiquark annihilation at the tree level and those from gluon-gluon fusion, which proceeds via quark and squark loops. We list compact results for the tree-level partonic cross sections and the squark loop amplitudes, and we confirm previous results for the quark loop amplitudes. We quantitatively analyze the hadronic cross sections at the CERN Large Hadron Collider assuming a favorable supergravity-inspired scenario.

  17. Associated production of Z and neutral Higgs bosons at the CERN Large Hadron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Kniehl, Bernd A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Palisoc, Caesar P. [Univ. of the Philippines, Diliman, Quezon City (Philippines). National Inst. of Physics

    2011-12-15

    We study the hadroproduction of a CP-even or CP-odd neutral Higgs boson in association with a Z boson in the minimal supersymmetric extension of the standard model (MSSM) We include the contributions from quark-antiquark annihilation at the tree level and those from gluon-gluon fusion, which proceeds via quark and squark loops, and list compact analytic results. We quantitatively analyze the hadronic cross sections at the CERN Large Hadron Collider assuming a favorable supergravity-inspired MSSM scenario. (orig.)

  18. Commissioning and Operation of the ATLAS Pixel Detector at the CERN LHC Collider

    CERN Document Server

    Djama, F; The ATLAS collaboration

    2010-01-01

    Physics program at the CERN LHC collider started in autumn 2009. Since then, LHC daily delivers collisions between its two proton beams. This talk was devoted to the commissioning and early operation of the ATLAS Pixel Detector. The Pixel Detector is working nicely and all the required performances like efficiency, resolution and low noise were met. The fraction of working modules is as high as 97.4 %. The Pixel Detector fully participates in the reconstruction of charged particles trajectories, and is a key element in finding primary and secondary verticies and in tagging of short-lived particles.

  19. Lower limit on dark matter production at the CERN Large Hadron Collider.

    Science.gov (United States)

    Feng, Jonathan L; Su, Shufang; Takayama, Fumihiro

    2006-04-21

    We evaluate the prospects for finding evidence of dark matter production at the CERN Large Hadron Collider. We consider weakly interacting massive particles (WIMPs) and superWIMPs and characterize their properties through model-independent parametrizations. The observed relic density then implies lower bounds on dark matter production rates as functions of a few parameters. For WIMPs, the resulting signal is indistinguishable from background. For superWIMPs, however, this analysis implies significant production of metastable charged particles. For natural parameters, these rates may far exceed Drell-Yan cross sections and yield spectacular signals.

  20. W production at large transverse momentum at the CERN Large Hadron Collider.

    Science.gov (United States)

    Gonsalves, Richard J; Kidonakis, Nikolaos; Sabio Vera, Agustín

    2005-11-25

    We study the production of W bosons at large transverse momentum in pp collisions at the CERN Large Hadron Collider. We calculate the complete next-to-leading order (NLO) corrections to the differential cross section. We find that the NLO corrections provide a large increase to the cross section but, surprisingly, do not reduce the scale dependence relative to leading order (LO). We also calculate next-to-next-to-leading-order (NNLO) soft-gluon corrections and find that, although they are small, they significantly reduce the scale dependence thus providing a more stable result.

  1. Measurement of very large transverse momentum jet production at the CERN anti pp collider

    International Nuclear Information System (INIS)

    The production of very large transverse momentum hadron jets has been measured in the UA2 experiment at the CERN anti pp Collider for √s = 540 GeV using a highly segmented calorimeter. The range of previously available cross sections for inclusive jet production is extended to psub(T) = 150 GeV and the two-jet invariant mass distribution to msub(jj) = 280 GeV with the largely increased data sample collected during the 1983 running period. The results are compared with the predictions of QCD models. (orig.)

  2. $W^{+-}$-production in $e^{-}$ p-collisions at CERN LEP/LHC energies with a non-standard $W^{+-}$ anomalous magnetic moment

    CERN Document Server

    Gutiérrez-Rodríguez, A

    2000-01-01

    We discuss the production of charged bosons in deep inelastic e-p- scattering, in the context of an electroweak model, in which the vector boson self interactions may be different from those prescribed by the electroweak standard model. We present results which show the strong dependence of the cross section on the anomalous magnetic dipole moment kappa of the W/sup +or-/. We show that even small deviations from the standard model value of kappa ( kappa =1) implies an observable deviation in the W/sup +or-/-production rates at CERN LEP/LHC energies. We also show that for the analysis of the charged boson production via e/sup -/p collisions at LEP/LHC energies will be very important to include the contribution from heavy boson exchange diagrams to the cross section rates. (25 refs).

  3. From the LHC to future colliders. CERN Theory Institute summary report

    Energy Technology Data Exchange (ETDEWEB)

    Roeck, A. de [CERN, Dept. of Physics, Geneva (Switzerland); Univ. of Antwerp, Wilrijk (Belgium); Ellis, J.; Wells, J.; Gripaios, B.; Dittmar, M. [CERN, Dept. of Physics, Geneva (Switzerland); Grojean, C. [CERN, Dept. of Physics, Geneva (Switzerland); CEA, Saclay (France); Heinemeyer, S. [Inst. de Fisica de Cantabria, CSIC-UC, Santander (Spain); Jakobs, K.; Schumacher, M.; Duehrssen, M. [Albert-Ludwigs-Univ., Physikalisches Inst., Freiburg (Germany); Weiglein, G.; Moortgat-Pick, G.; Morton-Thurtle, V.; Rolbiecki, K.; Smillie, J.; Tattersall, J. [Univ. of Durham, IPPP, Durham (United Kingdom); Azuelos, G. [Univ. de Montreal, Montreal (Canada); TRIUMF, Vancouver (Canada); Dawson, S.; Assamagan, K.; Gopalakrishna, S. [Brookhaven National Lab., Upton, NY (United States); Han, T. [Univ. of Wisconsin, Dept. of Physics, Madison (United States); Hewett, J.; Rizzo, T. [SLAC National Accelerator Lab., Menlo Park (United States); Lancaster, M.; Ozcan, E. [UCL, London (United Kingdom); Mariotti, C. [Sezione di Torino, INFN, Torino (Italy); Moortgat, F. [ETH Honggerberg, Dept. of Physics, Zurich (Switzerland); Polesello, G. [Sezione di Pavia, INFN, Pavia (Italy); Riemann, S.; Bechtle, P. [DESY, Hamburg (Germany); Carena, M.; Juste, A. [Fermi National Accelerator Lab., Batavia (United States); Chachamis, G. [Paul Scherrer Inst., Villigen (Switzerland); Chen, K.F.; Hou, W.S. [National Taiwan Univ., Dept. of Physics, Taipei (China); Curtis, S. de [Univ. of Florence (Italy); INFN, Dept. of Physics, Sezione di Firenze (Italy); Desch, K.; Wienemann, P. [Univ. Bonn, Physikalisches Inst., Bonn (Germany); Dreiner, H. [Bonn Univ., Bethe Center for Theoretical Physics and Physikalisches Inst., Bonn (Germany); Foster, B. [Univ. of Oxford, Particle Physics, Oxford (United Kingdom); Frandsen, M.T. [Univ. of Southern Denmark, CP3 - Origins, Odense (Denmark); Univ. of Oxford, Rudolf Peierls Centre for Theoretical Physics, Oxford (United Kingdom)] [and others

    2010-04-15

    Discoveries at the LHC will soon set the physics agenda for future colliders. This report of a CERN Theory Institute includes the summaries of Working Groups that reviewed the physics goals and prospects of LHC running with 10 to 300 fb{sup -1} of integrated luminosity, of the proposed sLHC luminosity upgrade, of the ILC, of CLIC, of the LHeC and of a muon collider. The four Working Groups considered possible scenarios for the first 10 fb{sup -1} of data at the LHC in which (i) a state with properties that are compatible with a Higgs boson is discovered, (ii) no such state is discovered either because the Higgs properties are such that it is difficult to detect or because no Higgs boson exists, (iii) a missing-energy signal beyond the Standard Model is discovered as in some supersymmetric models, and (iv) some other exotic signature of new physics is discovered. In the contexts of these scenarios, the Working Groups reviewed the capabilities of the future colliders to study in more detail whatever new physics may be discovered by the LHC. Their reports provide the particle physics community with some tools for reviewing the scientific priorities for future colliders after the LHC produces its first harvest of new physics from multi-TeV collisions. (orig.)

  4. Heavy flavour production and heavy flavour mixing at the CERN proton-antiproton collider

    International Nuclear Information System (INIS)

    In this thesis some results of the proton-antiproton-collision experiment UA1 with the CERN Super Proton-Antiproton Synchrotron are presented and interpreted. Ch. 1 contians a general introduction to the physics motivations behind the proton-antiproton-collider project, a brief description of the CERN facilities and a summary of collider and UA1 physics achievements. Furthermore the concept of studying heavy flavours via their weak decays into muons is introduced. Ch. 2 gives a brief overview of the UA1 experimental set-up, while those parts of the detector that are relevant for the analysis, presented in this thesis, is discussed in some more detail. Ch. 3 contains a short introduction to, and motivation for the use of Monte Carlo techniques in event simulations, while Ch. 4 describes the framework of the recently developed 'EUROJET' event generator. In Ch. 5 a treatment is given of the theoretical background and concepts like 'quark-mixing' and 'CP-violation' are explained, also other useful definitions and formulae are introduced on which the later analysis of the same-sign to opposite-sign dimuon ratio is built. Data collection and event reconstruction is the subject of Ch. 6, while a detailed comparison between the theoretical models and experimentally obtained distributions is given in Ch. 7. Finally, in Ch. 8 some concluding remarks are made. 182 refs.; 81 figs.; 9 tabs

  5. The Large Hadron Collider (LHC). The worlds largest vacuum system is working at CERN; El Large Hadron Collider (LHC). El sistema de vacio mas grande del mundo esta operando en el CERN

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez y Carvajal, J. M.

    2010-07-01

    When the September 10, 2008, was put into service at CERN, the Large Hadron Collider, the LHC (Large Hadron Collider) particle accelerator Giant left the imagination of particle physicists High Energy, began the most ambitious experiment in the field of Particle Physics High Energy. It expected to lead to the discovery of the predicted Higgs boson or could reveal new physics beyond the Standard Model. (author)

  6. LEP Traceability

    CERN Document Server

    Billen, R

    2000-01-01

    After more than ten years of production for high energy physics, CERN's current flagship, LEP, will be closed down definitively October 1st, 2000. Starting immediately, some 30,000 tonnes of LEP materials will be removed from the tunnel to make room for LHC installation. The dismantling project is a major undertaking in terms of resources and constraints, which has to be completed in less than one year. Moreover, since LEP is classified as a nuclear installation in France (as if it was a nuclear power plant), special procedures have to be followed in addition to the normal environmental and safety issues. One major facet of the project is the "traceability" of everything that comes out of the LEP tunnel. This implies that each piece of equipment must be identified and tracked from its origin through any temporary storage to its final destination. Special procedures have to be followed for all materials even if they are not radioactive. As much of the equipment as possible will be recycled or disposed of. This...

  7. The LEP project Lifting the curtain on physics of the year 2000

    CERN Document Server

    Kanel, A

    1982-01-01

    Describes some of the work carried out by CERN, particularly that concerning the proton and neutron. A few details are given of installed plant for this type of research. The author deals particularly with the LEP machine (Large Electron Positron collider). The reasons for having such a machine are given and this is followed by a description of some of the techniques used. Public fears have been raised concerning the project and, because of this, CERN has organised three public debates at Geneva for discussion of all aspects involved. These include atom bombs, nuclear energy, and stocking of radioactive waste material. There have been some threats of sabotage regarding the LEP installation.

  8. 1990 CERN School of Physics

    International Nuclear Information System (INIS)

    The CERN School of Physics is intended to give young experimental physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These Proceedings contain reports of lectures on the following topics: Field theory, electroweak theory, physics beyond the Standard Model, QCD, heavy flavours and CP violation, results from LEP experiments, particle accelerator technology, tau charm factories, and the Large Hadron Collider project. (orig.)

  9. From the LHC to Future Colliders CERN Theory Institute Summary Report

    CERN Document Server

    de Roeck, A; Grojean, C; Heinemeyer, S; Jakobs, K; Weiglein, G; Wells, J; Azuelos, Georges; Dawson, S; Gripaios, B; Han, T; Hewett, J; Lancaster, M; Mariotti, C; Moortgat, F; Moortgat-Pick, G; Polesello, G; Riemann, S; Schumacher, M; Assamagan, K; Bechtle, P; Carena, M S; Chachamis, G; Chen, K F; De Curtis, S; Desch, K; Dittmar, M; Dreiner, H; Dührssen, M; Frandsen, M T; Giammanco, A; Godbole, R; Govoni, P; Gunion, J F; Hollik, W; Hou, W S; Isidori, G; Juste, A; Kalinowski, J; Korytov, A; Kou, E; Kraml, S; Krawczyk, M; Martin, A; Milstead, D; Morton-Thurtle, V; Mönig, K; Melé, B; Pieri, M; Plehn, T; Reina, L; Richter-Was, E; Rizzo, T; Rolbiecki, K; Sannino, F; Schram, M; Smillie, J; Sultansoy, S; Uwer, P

    2010-01-01

    Discoveries at the LHC will soon set the physics agenda for future colliders. This report of a CERN Theory Institute includes the summaries of Working Groups that reviewed the physics goals and prospects of LHC running with 10 to 300/fb of integrated luminosity, of the proposed sLHC luminosity upgrade, of the ILC, of CLIC, of the LHeC and of a muon collider. The four Working Groups considered possible scenarios for the first 10/fb of data at the LHC in which (i) a state with properties that are compatible with a Higgs boson is discovered, (ii) no such state is discovered either because the Higgs properties are such that it is difficult to detect or because no Higgs boson exists, (iii) a missing-energy signal beyond the Standard Model is discovered as in some supersymmetric models, and (iv) some other exotic signature of new physics is discovered. In the contexts of these scenarios, the Working Groups reviewed the capabilities of the future colliders to study in more detail whatever new physics may be discover...

  10. Observation of Single Isolated Electrons of High Transverse Momentum in Events with Missing Transverse Energy at the CERN pp Collider

    DEFF Research Database (Denmark)

    Banner, M.; Kofoed-Hansen, O.

    1983-01-01

    We report the results of a search for single isolated electrons of high transverse momentum at the CERN collider. Above 15 GeV/c, four events are found having large missing transverse energy along a direction opposite in azimuth to that of the high-pT electron. Both the configuration of the events...

  11. Transmission Line Analysis of the Superconducting Quadrupole Chains of the LHC Collider at CERN

    CERN Document Server

    Dahlerup-Petersen, K

    2003-01-01

    Key information for determination of fundamental design features of magnet powering and protection circuits can be retrieved from the results of transmission line calculations of the superconducting magnet chains in a particle accelerator. Modelling and simulation of the behaviour of long magnet strings provide important data for the expected electrical behaviour and performances under all operating conditions. The presented results of a transmission line study concerns the sixteen superconducting main quadrupole chains QF/QD of CERN's future LHC collider. The paper details the elaboration of the synthesized electrical model of the individual quadrupoles and the associated lumped transmission line. It presents results on the current ripple for a given converter voltage output characteristics, the magnet excitation, leakage and earth currents during the ramping procedure, the impedance resonance spectrum and the need for individual magnet damping and the propagation, reflection, superposition and damping of th...

  12. Parton distribution functions probed in ultraperipheral collisions at the CERN Large Hadron Collider

    CERN Document Server

    Thomas, J; Brady, N; Clark, D B; Godat, E; Olness, F

    2016-01-01

    Vector meson production in ultra-peripheral pA and AA collisions at the CERN Large Hadron Collider (LHC) are very sensitive to Parton Distribution Functions (PDF) as well as to their leading-order, next-to-leading-order, and medium corrections. This process is a complimentary tool to explore the effects of different PDFs in particle production in proton-nucleus and nucleus-nucleus central collisions. Existing and forthcoming data available, e.g., from ALICE and CMS, may be used in conjunction with our theoretical predictions to constrain the PDFs. We make predictions for rapidity distributions and for cross sections of J/$\\psi$ , $\\psi(2S)$ and $\\Upsilon$ production at $\\sqrt{s_{NN}}=2.76$ TeV and $\\sqrt{s_{NN}}=5$ TeV. We use the second energy as representative for the Run 2 of PbPb collisions at the LHC.

  13. The Radiological Situation in the Beam-Cleaning Sections of the CERN Large Hadron Collider (LHC)

    CERN Document Server

    Brugger, Markus; Stevenson, Graham

    2003-01-01

    This thesis contributes to radiological assessments of the design and operation of the Large Hadron Collider currently under construction at CERN. In particular, the scope of this thesis is to examine the beam cleaning insertions - two of the main loss regions of the LHC where beam particles which would otherwise cause unwanted losses at different places of the machine are purposely intercepted. Two critical issues with regard to the protection of personnel and environment are studied: remanent dose rates due to induced radioactivity and airborne radioactivity. Although a detailed estimate of remanent dose rates is important for an optimization of later maintenance interventions only very limited information on remanent dose rates to be expected around the collimators was available so far. This thesis is an attempt to extend the knowledge considerably, especially by applying a new calculational method. Since this new approach is used for the first time in the design of the LHC a careful benchmarking with expe...

  14. Black holes in many dimensions at the CERN large Hadron collider testing critical string theory

    CERN Document Server

    Hewett, J L; Rizzo, T G; Hewett, JoAnne L.; Lillie, Ben; Rizzo, Thomas G.

    2005-01-01

    We consider black hole production at the CERN Large Hadron Collider (LHC) in a generic scenario with many extra dimensions where the standard model fields are confined to a brane. With ~20 dimensions the hierarchy problem is shown to be naturally solved without the need for large compactification radii. We find that in such a scenario the properties of black holes can be used to determine the number of extra dimensions, n. In particular, we demonstrate that measurements of the decay distributions of such black holes at the LHC can determine if n is significantly larger than 6 or 7 with high confidence and thus can probe one of the critical properties of string theory compactifications.

  15. Black holes in many dimensions at the CERN Large Hadron Collider: testing critical string theory.

    Science.gov (United States)

    Hewett, JoAnne L; Lillie, Ben; Rizzo, Thomas G

    2005-12-31

    We consider black hole production at the CERN Large Hadron Collider (LHC) in a generic scenario with many extra dimensions where the standard model fields are confined to a brane. With approximately 20 dimensions the hierarchy problem is shown to be naturally solved without the need for large compactification radii. We find that in such a scenario the properties of black holes can be used to determine the number of extra dimensions, . In particular, we demonstrate that measurements of the decay distributions of such black holes at the LHC can determine if is significantly larger than 6 or 7 with high confidence and thus can probe one of the critical properties of string theory compactifications.

  16. Landscape of supersymmetric particle mass hierarchies and their signature space at the CERN Large Hadron Collider.

    Science.gov (United States)

    Feldman, Daniel; Liu, Zuowei; Nath, Pran

    2007-12-21

    The minimal supersymmetric standard model with soft breaking has a large landscape of supersymmetric particle mass hierarchies. This number is reduced significantly in well-motivated scenarios such as minimal supergravity and alternatives. We carry out an analysis of the landscape for the first four lightest particles and identify at least 16 mass patterns, and provide benchmarks for each. We study the signature space for the patterns at the CERN Large Hadron Collider by analyzing the lepton+ (jet> or =2) + missing P{T} signals with 0, 1, 2, and 3 leptons. Correlations in missing P{T} are also analyzed. It is found that even with 10 fb{-1} of data a significant discrimination among patterns emerges.

  17. PARTICLE PHYSICS: CERN Gives Higgs Hunters Extra Month to Collect Data.

    Science.gov (United States)

    Morton, O

    2000-09-22

    After 11 years of banging electrons and positrons together at higher energies than any other machine in the world, CERN, the European laboratory for particle physics, had decided to shut down the Large Electron-Positron collider (LEP) and install a new machine, the Large Hadron Collider (LHC), in its 27-kilometer tunnel. In 2005, the LHC will start bashing protons together at even higher energies. But tantalizing hints of a long-sought fundamental particle have forced CERN managers to grant LEP a month's reprieve.

  18. b-tagging in DELPHI at LEP

    CERN Document Server

    Abdallah, J; Adam, W; Adye, T; Adzic, P; Albrecht, T; Alderweireld, T; Alemany-Fernandez, R; Allmendinger, T; Allport, P P; Almehed, S; Amaldi, Ugo; Amapane, N; Amato, S; Anashkin, E; Andreazza, A; Andringa, S; Anjos, N; Antilogus, P; Apel, W D; Arnoud, Y; Ask, S; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Ballestrero, A; Bambade, P; Barbier, R; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Bates, M; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Behrmann, A; Benekos, N C; Benvenuti, Alberto C; Bérat, C; Berggren, M; Berntzon, L; Bertrand, D; Besançon, M; Besson, N; Bibby, J; Biffi, P; Bloch, D; Blom, M; Bonesini, M; Boonekamp, M; Booth, P S L; Borisov, G; Botner, O; Bouquet, B; Bowcock, T J V; Boyko, I; Bracko, M; Branchini, P; Brenner, R; Brodet, E; Brückman, P; Brunet, J M; Bugge, L; Buschmann, P; Caccia, M; Calvi, M; Camporesi, T; Canale, V; Carena, F; Castro, N; Cavallo, F R; Chabaud, V; Chapkin, M M; Charpentier, P; Checchia, P; Chierici, R; Shlyapnikov, P; Chudoba, J; Chung, S U; Cieslik, K; Collins, P; Contri, R; Cosme, G; Cossutti, F; Costa, M J; Couchot, F; Crawley, B; Crennell, D J; Cuevas-Maestro, J; D'Almagne, B; D'Hondt, J; Dalmau, J; Da Silva, T; Da Silva, W; Della Ricca, G; De Angelis, A; de Boer, Wim; De Clercq, C; De Lotto, B; De Maria, N; De Min, A; De Paula, L S; Di Ciaccio, Lucia; Dijkstra, H; Di Simone, A; Doroba, K; Drees, J; Dris, M; Eigen, G; Ekelöf, T J C; Ellert, M; Elsing, M; Espirito-Santo, M C; Fanourakis, G K; Fassouliotis, D; Feindt, M; Fernández, J; Ferrer, A; Ferro, F; Flagmeyer, U; Föth, H; Fokitis, E; Fulda-Quenzer, F; Fuster, J A; Gandelman, M; García, C; Gavillet, P; Gazis, E N; Geralis, T; Gokieli, R; Golob, B; Gómez-Cadenas, J J; Gómez-Ceballos, G; Gonçalves, P; Graziani, E; Grosdidier, G; Grzelak, K; Guy, J; Haag, C; Hallgren, A; Hamacher, K; Hamilton, K; Hansen, J; Haug, S; Hauler, F; Hedberg, V; Hennecke, M; Hernando, J A; Herr, H; Heuser, J M; Holmgren, S O; Holt, P J; Houlden, M A; Hultqvist, K; Jackson, J N; Jalocha, P; Jarlskog, C; Jarlskog, G; Jarry, P; Jeans, D; Johansson, E K; Johansson, P D; Jonsson, P; Joram, C; Jungermann, L; Kapusta, F; Karlsson, M; Katsanevas, S; Katsoufis, E C; Keränen, R; Kernel, G; Kersevan, Borut P; Kiiskinen, A P; King, B T; Kjaer, N J; Kluit, P; Kokkinias, P; Kourkoumelis, C; Kuznetsov, O; Krumshtein, Z; Kucharczyk, M; Kucewicz, W; Kurowska, J; Lamsa, J; Leder, G; Ledroit, F; Leinonen, L; Leitner, R; Lemonne, J; Lepeltier, V; Lesiak, T; Liebig, W; Liko, D; Lipniacka, A; Lopes, J H; López, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J; Malek, A; Maltezos, S; Mandl, F; Marco, J; Marco, R; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Martínez-Vidal, F; Masik, J; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Mazzucato, F; Mazzucato, M; McNulty, R; Meroni, C; Meyer, W T; Migliore, E; Mitaroff, W A; Mjörnmark, U; Moa, T; Moch, M; Mönig, K; Monge, R; Montenegro, J; Moraes, D; Moreno, S; Morettini, P; Müller, U; Münich, K; Mulders, M; Mundim, L; Murray, W; Muryn, B; Myatt, Gerald; Myklebust, T; Nassiakou, M; Navarria, Francesco Luigi; Nawrocki, K; Nicolaidou, R; Niezurawski, P; Nikolenko, M; Nomerotski, A; Norman, A; Nygren, A; Oblakowska-Mucha, A; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Österberg, K; Ouraou, A; Oyanguren, A; Paganoni, M; Paiano, S; Palacios, J P; Palka, H; Papadopoulou, T D; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Peralta, L; Perepelitsa, V F; Perrotta, A; Petrolini, A; Piedra, J; Pieri, L; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Poireau, V; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Pukhaeva, N; Pullia, Antonio; Rames, J; Ramler, L; Read, A; Rebecchi, P; Rehn, J; Reid, D; Reinhardt, R; Renton, P B; Richard, F; Rídky, J; Rivero, M; Rodríguez, D; Romero, A; Ronchese, P; Rosenberg, E I; Roudeau, Patrick; Rovelli, T; Ruhlmann-Kleider, V; Ryabtchikov, D; Sadovskii, A; Salmi, L; Salt, J; Savoy-Navarro, A; Schwickerath, U; Segar, A; Sekulin, R L; Siebel, M; Sissakian, A N; Smadja, G; Smirnova, O G; Sokolov, A; Sopczak, A; Sosnowski, R; Spassoff, Tz; Stanitzki, M; Stavitski, I; Stocchi, A; Strauss, J; Stugu, B; Szczekowski, M; Szeptycka, M; Szumlak, T; Tabarelli de Fatis, T; Taffard, A C; Tegenfeldt, F; Timmermans, J; Tinti, N; Tkatchev, L G; Tobin, M; Todorovova, S; Tomaradze, A G; Tomé, B; Tonazzo, A; Tortosa, P; Travnicek, P; Treille, D; Trischuk, W; Tristram, G; Trochimczuk, M; Troncon, C; Turluer, M L; Tyapkin, I A; Tyapkin, P; Tyndel, M; Tzamarias, S; Uvarov, V; Valenti, G; van Dam, P; Van Eldik, J; Van Lysebetten, A; Van Remortel, N; Van Vulpen, I B; Vegni, G; Veloso, F; Venus, W A; Verbeure, F; Verdier, P; Verzi, V; Vilanova, D; Vitale, L; Vrba, V; Wahlen, H; Washbrook, A J; Weilhammer, Peter; Weiser, C; Wicke, D; Wickens, J H; Wilkinson, G; Winter, M; Witek, M; Yushchenko, O P; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zimin, N I; Zinchenko, A I; Zupan, M

    2004-01-01

    The standard method used for tagging b-hadrons in the DELPHI experiment at the CERN LEP Collider is discussed in detail. The main ingredient of b-tagging is the impact parameters of tracks, which relies mostly on the vertex detector. Additional information, such as the mass of particles associated to a secondary vertex, significantly improves the selection efficiency and the background suppression. The paper describes various discriminating variables used for the tagging and the procedure of their combination. In addition, applications of b-tagging to some physics analyses, which depend crucially on the performance and reliability of b-tagging, are described briefly.

  19. Simulations and measurements of beam loss patterns at the CERN Large Hadron Collider

    CERN Document Server

    Bruce, R; Boccone, V; Bracco, C; Brugger, M; Cauchi, M; Cerutti, F; Deboy, D; Ferrari, A; Lari, L; Marsili, A; Mereghetti, A; Mirarchi, D; Quaranta, E; Redaelli, S; Robert-Demolaize, G; Rossi, A; Salvachua, B; Skordis, E; Tambasco, C; Valentino, G; Weiler, T; Vlachoudis, V; Wollmann, D

    2014-01-01

    The CERN Large Hadron Collider (LHC) is designed to collide proton beams of unprecedented energy, in order to extend the frontiers of high-energy particle physics. During the first very successful running period in 2010--2013, the LHC was routinely storing protons at 3.5--4 TeV with a total beam energy of up to 146 MJ, and even higher stored energies are foreseen in the future. This puts extraordinary demands on the control of beam losses. An un-controlled loss of even a tiny fraction of the beam could cause a superconducting magnet to undergo a transition into a normal-conducting state, or in the worst case cause material damage. Hence a multi-stage collimation system has been installed in order to safely intercept high-amplitude beam protons before they are lost elsewhere. To guarantee adequate protection from the collimators, a detailed theoretical understanding is needed. This article presents results of numerical simulations of the distribution of beam losses around the LHC that have leaked out of the co...

  20. Cryogenic Studies for the Proposed CERN Large Hadron Electron Collider (LHeC)

    CERN Document Server

    Haug, F

    2011-01-01

    The LHeC (Large Hadron electron Collider) is a proposed future colliding beam facility for lepton-nucleon scattering particle physics at CERN. A new 60 GeV electron accelerator will be added to the existing 27 km circumference 7 TeV LHC for collisions of electrons with protons and heavy ions. Two basic design options are being pursued. The first is a circular accelerator housed in the existing LHC tunnel which is referred to as the "Ring-Ring" version. Low field normal conducting magnets guide the particle beam while superconducting (SC) RF cavities cooled to 2 K are installed at two opposite locations at the LHC tunnel to accelerate the beams. For this version in addition a 10 GeV re-circulating SC injector will be installed. In total four refrigerators with cooling capacities between 1.2 kW and 3 kW @ 4.5 K are needed. The second option, referred to as the "Linac-Ring" version consists of a race-track re-circulating energy-recovery type machine with two 1 km long straight acceleration sections. The 944 hi...

  1. Lightening-like interactions in nuclear collisions at CERN large hadron collider

    CERN Document Server

    Abdel-Waged, Khaled

    2015-01-01

    A simple basic model for describing proton-nucleus (pA) and nucleus-nucleus (AA) collisions has been the intra-nuclear cascade model, where the interactions are simulated by a sequence of binary nucleon-nucleon (NN) collisions. This model helped to establish many scientific concepts and also creates the foundation for more modern simulation codes, especially at low and intermediate energies. In this paper, we present a new Monte Carlo model for pA and AA collisions at high CERN Large Hadron collider energies. The model implements HIJING code with a collective cascade recipe, that induces striking light-like effect in a large nucleus. A single collision (lightening) event is shown to be a complex process:A primary interacting nucleon passes its energy to the surrounding nucleons in a large nucleus. This new simulation code is shown to be good to reproduce the Large Hadron collider (LHC) data, especially the charged particle pseudorapidity density in p+Pb and Pb+Pb collisions at LHC energies.

  2. Fault Tracking of the Superconducting Magnet System at the CERN Large Hadron Collider

    CERN Document Server

    Griesemer, Tobias

    2016-03-25

    The Large Hadron Collider (LHC) at CERN is one of the most complex machines ever built. It is used to explore the mysteries of the universe by reproducing conditions of the big bang. High energy particles are collide in particle detectors and as a result of the collision process secondary particles are created. New particles could be discovered during this process. The operation of such a machine is not straightforward and is subject to many different types of failures. A model of LHC operation needs to be defined in order to understand the impact of the various failures on availability. As an example a typical operational cycle is described: the beams are first injected, then accelerated, and finally brought into collisions. Under nominal conditions, beams should be in collision (so-called ‘stable beams’ period) for about 10 hours and then extracted onto a beam dump block. In case of a failure, the Machine Protection Systems ensure safe extraction of the beams. From the experience in LHC Run 1 (2009 - 20...

  3. Heavy-ion physics with the ALICE experiment at the CERN Large Hadron Collider.

    Science.gov (United States)

    Schukraft, J

    2012-02-28

    After close to 20 years of preparation, the dedicated heavy-ion experiment A Large Ion Collider Experiment (ALICE) took first data at the CERN Large Hadron Collider (LHC) accelerator with proton collisions at the end of 2009 and with lead nuclei at the end of 2010. After a short introduction into the physics of ultra-relativistic heavy-ion collisions, this article recalls the main design choices made for the detector and summarizes the initial operation and performance of ALICE. Physics results from this first year of operation concentrate on characterizing the global properties of typical, average collisions, both in proton-proton (pp) and nucleus-nucleus reactions, in the new energy regime of the LHC. The pp results differ, to a varying degree, from most quantum chromodynamics-inspired phenomenological models and provide the input needed to fine tune their parameters. First results from Pb-Pb are broadly consistent with expectations based on lower energy data, indicating that high-density matter created at the LHC, while much hotter and larger, still behaves like a very strongly interacting, almost perfect liquid.

  4. Shimon Pérès visite le CERN

    CERN Multimedia

    CERN Press Office. Geneva

    1995-01-01

    Shimon Peres, Israel's Foreign Minister, made an official visit to CERN on 26 January. He was accompanied by the Israeli Ambassador to the International Organizations in Geneva, Yosef Lamdan, and was received by CERN's Director General, Prof. Christopher Llewellyn Smith. The visit took place at the site of the giant OPAL experiment, on the Large Electron Positron Collider (LEP), where there is major Israeli involvement.

  5. CERN Library | Pauline Gagnon presents the book "Who cares about particle physics? : making sense of the Higgs boson, the Large Hadron Collider and CERN" | 15 September

    CERN Multimedia

    CERN Library

    2016-01-01

    "Who cares about particle physics? : making sense of the Higgs boson, the Large Hadron Collider and CERN ", by Pauline Gagnon. Thursday 15 September 2016, 16:00 - 17:30 in the CERN Library (Bldg 52 1-052) *Coffee will be served at 15:30* CERN, the European Laboratory for particle physics, regularly makes the news. What kind of research happens at this international laboratory and how does it impact people's daily lives? Why is the discovery of the Higgs boson so important? Particle physics describes all matter found on Earth, in stars and all galaxies but it also tries to go beyond what is known to describe dark matter, a form of matter five times more prevalent than the known, regular matter. How do we know this mysterious dark matter exists and is there a chance it will be discovered soon? About sixty countries contributed to the construction of the gigantic Large Hadron Collider (LHC) at CERN and its immense detectors. Dive in to discover how international teams of researchers...

  6. CERN moves into the LHC era

    CERN Multimedia

    2001-01-01

    Dr Hans Eschelbacher (on the left), President of the CERN Council for the last three years, hands over to his successor Maurice Bourquin.  The CERN Council, where the representatives of the 20 Member States of the Organization decide on scientific programmes and financial resources, held its 116th session on 15 December under the chairmanship of Dr. Hans C. Eschelbacher (DE). 'Le Roi est mort. Vive le Roi !' The Large Electron Positron Collider (LEP) era has ended and CERN's future is the Large Hadron Collider (LHC), stated Director General, Prof. Luciano Maiani. He opened his report to Council with a 'homage to LEP', which reached the end of its career during 2000 and is now being dismantled to make way for CERN's next major machine, the LHC collider, in the same 27-kilometre tunnel. The strong indications of a Higgs boson at 115 GeV found during the year were the culmination of LEP's long and distinguished physics career, during which the machine opened up new regimes of precision physics, involvi...

  7. Experiments at CERN in 1997

    International Nuclear Information System (INIS)

    This book summarises the current experimental programme at CERN. The experiments listed are taking place at one of the following machines: the Large Electron Positron Collider (LEP), the Super Proton Synchroton (SPS), the 28 GeV Proton Synchrotron (PS), including the Antiproton Decelerator (AD) for slow antiprotons and the ISOLDE facility for short-lived ions. The three experiments now approved for installation at the Large Hadron Collider (LHC) and the R and D projects aimed at the development of new detector technologies and data acquisition systems for the LHC experiments are also listed. (orig./WL)

  8. LEP shuts down after eleven years of forefront research

    CERN Multimedia

    2000-01-01

    After extended consultation with the appropriate scientific committees, CERN’s Director-General Luciano Maiani announced today that the LEP accelerator had been switched off for the last time. LEP was scheduled to close at the end of September 2000 but tantalising signs of possible new physics led to LEP’s run being extended until 2 November. At the end of this extra period, the four LEP experiments had produced a number of collisions compatible with the production of Higgs particles with a mass of around 115 GeV. These events were also compatible with other known processes. The new data was not sufficiently conclusive to justify running LEP in 2001, which would have inevitable impact on LHC construction and CERN’s scientific programme. The CERN Management decided that the best policy for the Laboratory is to proceed full-speed ahead with the Large Hadron Collider (LHC) project. Steve Myers, Head of SL Division, with members of the LEP team, pulling the symbolic rope to swich off the accelerator. CERN Co...

  9. Follow-up research at CERN

    International Nuclear Information System (INIS)

    At The European Center for High Energy Physics (Conseil Europeen de Recherche Nucleaire - CERN) basic research is carried out based on some of the world's largest particle accelerators, especially the Large Electron Positron collider (LEP). Danish membership of CERN gives Danish physicists access to these machines and the Accelerator Committee offers advice on their utilization and related financing. Danish research carried out at CERN is described, based on contributions from individual research groups. The functions, administration and budgets of the Accelerator Committee are explained in addition to other forms of administration connected with CERN, such as the Danish CERN Delegation, and an evaluation of Danish experimentation within physics is presented. Information is given on individual Danish members of the CERN groups of scientists and a list of the publications of international research groups which include Danish subjects, covering the years 1991-93, is presented. The publication is related to the delegation of grants for research projects carried out by Danish physicists. (AB)

  10. Development of a beam condition monitor for use in experiments at the CERN Large Hadron Collider using synthetic diamond

    CERN Document Server

    Fernández-Hernando, L; Ilgner, C; MacPherson, A; Oh, A; Pernegger, H; Pritchard, T; Stone, R; Worm, S

    2004-01-01

    The CERN Large Hadron Collider (LHC) will collide two counter rotating proton beams, each with a store energy about 350MJ; enough to melt 550kg of copper. If there is failure in an element of the accelerator, the resulting beam losses could cause damage not only to the machine but also to the experiments. A Beam Condition Monitor (BCM) is foreseen to monitor last increments of particle flux near the interaction point and if necessary, to generate an abort signal to the LHC accelerator control, to dump the beams. Due to its radiation hardness and minimal services requirements, synthetic CVD diamond is being considered as BCM sensor option. (12 refs).

  11. Simulations and measurements of beam loss patterns at the CERN Large Hadron Collider

    Science.gov (United States)

    Bruce, R.; Assmann, R. W.; Boccone, V.; Bracco, C.; Brugger, M.; Cauchi, M.; Cerutti, F.; Deboy, D.; Ferrari, A.; Lari, L.; Marsili, A.; Mereghetti, A.; Mirarchi, D.; Quaranta, E.; Redaelli, S.; Robert-Demolaize, G.; Rossi, A.; Salvachua, B.; Skordis, E.; Tambasco, C.; Valentino, G.; Weiler, T.; Vlachoudis, V.; Wollmann, D.

    2014-08-01

    The CERN Large Hadron Collider (LHC) is designed to collide proton beams of unprecedented energy, in order to extend the frontiers of high-energy particle physics. During the first very successful running period in 2010-2013, the LHC was routinely storing protons at 3.5-4 TeV with a total beam energy of up to 146 MJ, and even higher stored energies are foreseen in the future. This puts extraordinary demands on the control of beam losses. An uncontrolled loss of even a tiny fraction of the beam could cause a superconducting magnet to undergo a transition into a normal-conducting state, or in the worst case cause material damage. Hence a multistage collimation system has been installed in order to safely intercept high-amplitude beam protons before they are lost elsewhere. To guarantee adequate protection from the collimators, a detailed theoretical understanding is needed. This article presents results of numerical simulations of the distribution of beam losses around the LHC that have leaked out of the collimation system. The studies include tracking of protons through the fields of more than 5000 magnets in the 27 km LHC ring over hundreds of revolutions, and Monte Carlo simulations of particle-matter interactions both in collimators and machine elements being hit by escaping particles. The simulation results agree typically within a factor 2 with measurements of beam loss distributions from the previous LHC run. Considering the complex simulation, which must account for a very large number of unknown imperfections, and in view of the total losses around the ring spanning over 7 orders of magnitude, we consider this an excellent agreement. Our results give confidence in the simulation tools, which are used also for the design of future accelerators.

  12. Analysis of the Laser Calibration System for the CMS HCAL at CERN's Large Hadron Collider

    Science.gov (United States)

    Lebolo, Luis

    2005-11-01

    The European Organization for Nuclear Physics' (CERN) Large Hadron Collider uses the Compact Muon Solenoid (CMS) detector to measure collision products from proton-proton interactions. CMS uses a hadron calorimeter (HCAL) to measure the energy and position of quarks and gluons by reconstructing their hadronic decay products. An essential component of the detector is the calibration system, which was evaluated in terms of its misalignment, linearity, and resolution. In order to analyze the data, the authors created scripts in ROOT 5.02/00 and C++. The authors also used Mathematica 5.1 to perform complex mathematics and AutoCAD 2006 to produce optical ray traces. The misalignment of the optical components was found to be satisfactory; the Hybrid Photodiodes (HPDs) were confirmed to be linear; the constant, noise and stochastic contributions to its resolution were analyzed; and the quantum efficiency of most HPDs was determined to be approximately 40%. With a better understanding of the laser calibration system, one can further understand and improve the HCAL.

  13. The Thermosiphon Cooling System of the ATLAS Experiment at the CERN Large Hadron Collider

    CERN Document Server

    Battistin, M; Bitadze, A; Bonneau, P; Botelho-Direito, J; Boyd, G; Corbaz, F; Crespo-Lopez, O; Da Riva, E; Degeorge, C; Deterre, C; DiGirolamo, B; Doubek, M; Favre, G; Godlewski, J; Hallewell, G; Katunin, S; Lefils, D; Lombard, D; McMahon, S; Nagai, K; Robinson, D; Rossi, C; Rozanov, A; Vacek, V; Zwalinski, L

    2015-01-01

    The silicon tracker of the ATLAS experiment at CERN Large Hadron Collider will operate around –15°C to minimize the effects of radiation damage. The present cooling system is based on a conventional evaporative circuit, removing around 60 kW of heat dissipated by the silicon sensors and their local electronics. The compressors in the present circuit have proved less reliable than originally hoped, and will be replaced with a thermosiphon. The working principle of the thermosiphon uses gravity to circulate the coolant without any mechanical components (compressors or pumps) in the primary coolant circuit. The fluorocarbon coolant will be condensed at a temperature and pressure lower than those in the on-detector evaporators, but at a higher altitude, taking advantage of the 92 m height difference between the underground experiment and the services located on the surface. An extensive campaign of tests, detailed in this paper, was performed using two small-scale thermosiphon systems. These tests confirmed th...

  14. The CERN Large Hadron Collider as a tool to study high-energy density matter.

    Science.gov (United States)

    Tahir, N A; Kain, V; Schmidt, R; Shutov, A; Lomonosov, I V; Gryaznov, V; Piriz, A R; Temporal, M; Hoffmann, D H H; Fortov, V E

    2005-04-01

    The Large Hadron Collider (LHC) at CERN will generate two extremely powerful 7 TeV proton beams. Each beam will consist of 2808 bunches with an intensity per bunch of 1.15x10(11) protons so that the total number of protons in one beam will be about 3x10(14) and the total energy will be 362 MJ. Each bunch will have a duration of 0.5 ns and two successive bunches will be separated by 25 ns, while the power distribution in the radial direction will be Gaussian with a standard deviation, sigma=0.2 mm. The total duration of the beam will be about 89 mus. Using a 2D hydrodynamic code, we have carried out numerical simulations of the thermodynamic and hydrodynamic response of a solid copper target that is irradiated with one of the LHC beams. These calculations show that only the first few hundred proton bunches will deposit a high specific energy of 400 kJ/g that will induce exotic states of high energy density in matter.

  15. The CERN Large Hadron Collider as a tool to study high-energy density matter

    CERN Document Server

    Tahir, N A; Gryaznov, V; Hoffmann, Dieter H H; Kain, V; Lomonosov, I V; Piriz, A R; Schmidt, R; Shutov, A; Temporal, M

    2005-01-01

    The Large Hadron Collider (LHC) at CERN will generate two extremely powerful 7 TeV proton beams. Each beam will consist of 2808 bunches with an intensity per bunch of 1.15*10/sup 11/ protons so that the total number of protons in one beam will be about 3*10/sup 14/ and the total energy will be 362 MJ. Each bunch will have a duration of 0.5 ns and two successive bunches will be separated by 25 ns, while the power distribution in the radial direction will be Gaussian with a standard deviation, sigma =0.2 mm. The total duration of the beam will be about 89 mu s. Using a 2D hydrodynamic code, we have carried out numerical simulations of the thermodynamic and hydrodynamic response of a solid copper target that is irradiated with one of the LHC beams. These calculations show that only the first few hundred proton bunches will deposit a high specific energy of 400 kJ/g that will induce exotic states of high energy density in matter.

  16. Evidence for the color-octet mechanism from CERN LEP2 gamma gamma --> J/psi + X Data.

    Science.gov (United States)

    Klasen, Michael; Kniehl, Bernd A; Mihaila, Luminiţa N; Steinhauser, Matthias

    2002-07-15

    We present theoretical predictions for the transverse-momentum distribution of J/psi mesons promptly produced in gammagamma collisions within the factorization formalism of nonrelativistic quantum chromodynamics, including the contributions from both direct and resolved photons, and we perform a conservative error analysis. The fraction of J/psi mesons from decays of bottom-flavored hadrons is estimated to be negligibly small. New data taken by the DELPHI Collaboration at LEP2 nicely confirm these predictions, while they disfavor those obtained within the traditional color-singlet model.

  17. Prompt D*+ production in proton-proton and lead-lead collisions, measured with the ALICE experiment at the CERN Large Hadron Collider

    NARCIS (Netherlands)

    de Rooij, R. S.

    2013-01-01

    In this thesis the results are presented of the first measurements of the D*+ meson nuclear modification factor RAA in heavy ion collisions at the Large Hadron Collider (LHC) using the ALICE (A Large Ion Collider Experiment) detector at CERN. These open charmed mesons are a useful tool to investigat

  18. Measured and simulated heavy-ion beam loss patterns at the CERN Large Hadron Collider

    Science.gov (United States)

    Hermes, P. D.; Bruce, R.; Jowett, J. M.; Redaelli, S.; Salvachua Ferrando, B.; Valentino, G.; Wollmann, D.

    2016-05-01

    The Large Hadron Collider (LHC) at CERN pushes forward to new regimes in terms of beam energy and intensity. In view of the combination of very energetic and intense beams together with sensitive machine components, in particular the superconducting magnets, the LHC is equipped with a collimation system to provide protection and intercept uncontrolled beam losses. Beam losses could cause a superconducting magnet to quench, or in the worst case, damage the hardware. The collimation system, which is optimized to provide a good protection with proton beams, has shown a cleaning efficiency with heavy-ion beams which is worse by up to two orders of magnitude. The reason for this reduced cleaning efficiency is the fragmentation of heavy-ion beams into isotopes with a different mass to charge ratios because of the interaction with the collimator material. In order to ensure sufficient collimation performance in future ion runs, a detailed theoretical understanding of ion collimation is needed. The simulation of heavy-ion collimation must include processes in which 82+208Pb ions fragment into dozens of new isotopes. The ions and their fragments must be tracked inside the magnetic lattice of the LHC to determine their loss positions. This paper gives an overview of physical processes important for the description of heavy-ion loss patterns. Loss maps simulated by means of the two tools ICOSIM [1,2] and the newly developed STIER (SixTrack with Ion-Equivalent Rigidities) are compared with experimental data measured during LHC operation. The comparison shows that the tool STIER is in better agreement.

  19. CERN, Geneva

    CERN Multimedia

    2007-01-01

    "The Large Hadron Collider (pages 1-3) is being built at CERN, the European Centre for Nuclear Research near Geneva. CERN offers some extremely exciting opportunities to see "big bang" in action. (1 page)

  20. Studies of the single sided FOXFET biased detectors used in the OPAL experiment at LEP

    International Nuclear Information System (INIS)

    The OPAL Microvertex Detector, installed in March 1993 at the CERN LEP collider, uses single sided 250 μm thick FOXFET biased detectors. Construction of the detector required systematic studies of detector properties in order to ascertain desirable characteristics of detectors used in the final construction. We present measurements based on a pool of more than 200 detectors, including properties such as visual quality, FET characteristics, and leakage currents. ((orig.))

  1. First Lecture of Collide@CERN Geneva for Dance and Performance: Gilles Jobin artist in residency and his inspiration partner Joao Pequenao

    CERN Document Server

    CERN. Geneva

    2012-01-01

    CERN, jointly with Canton and City of Geneva, presents the public lecture of Gilles Jobin, the first winner of the Prix Collide@CERN Geneva, residency award for Dance and Performance arts, and his inspiration partner. They will present their work in dance and science at the CERN Globe of Science and Innovation on Wendesday 23 May 2012 at 19h (open doors at 18.30h) Refreshments will be served afterwards. Please reserve your places for you and your friends by contacting merce.monje.cano@cern.ch. +41 22 76 75246 We very much look forward to seeing you there.

  2. Lecture | CERN prepares its long-term future: a 100-km circular collider to follow the LHC? | CERN Globe | 11 March

    CERN Multimedia

    2015-01-01

    Particle physics is a long-term field of research: the LHC was originally conceived in the 1980s, but did not start running until 25 years later. An accelerator unlike any other, it is now just at the start of a programme that is set to run for another 20 years.   Frédérick Bordry. While the LHC programme is already well defined for the next two decades, it is now time to look even further ahead, and so CERN is initiating an exploratory study for a future long-term project centred on a next-generation circular collider with a circumference of 80 to 100 kilometres. A worthy successor to the LHC, whose collision energies will reach 13 TeV in 2015, such an accelerator would allow particle physicists to push the boundaries of knowledge even further. The Future Circular Collider (FCC) programme will focus especially on studies for a hadron collider, like the LHC, capable of reaching unprecedented energies in the region of 100 TeV. Opening with an introduction to the LHC and...

  3. Sprint final pour le LEP

    CERN Document Server

    CERN Press Office. Geneva

    2000-01-01

    Director General's Status Report The Director General, Prof. Luciano Maiani, began his report with the performance of the Laboratory's flagship accelerator, the Large Electron-Positron collider, LEP, during its final year. LEP is achieving its highest energy collisions ever with beams of over 104 GeV, well exceeding its design energy and giving experiments a final chance of discovering the still-elusive Higgs particles before the end of it's experimental programme in September. Thanks to precision data from LEP and elsewhere, scientists already know that Higgs particles, if they exist, must be within range of LEP's successor, the LHC.

  4. Cryogenic testing of by-pass diode stacks for the superconducting magnets of the Large Hadron Collider at CERN

    CERN Document Server

    Della Corte, A; Hagedorn, Dietrich; Turtu, S; Basile, G L; Catitti, A; Chiarelli, S; Di Ferdinando, E; Taddia, G; Talli, M; Verdini, L; Viola, R

    2002-01-01

    A dedicated facility prepared by ENEA (Italian Agency for Energy and Environment) for the cryogenic testing of by-pass diodes for the protection of the CERN Large Hadron Collider main magnets will be described. This experimental activity is in the frame of a contract awarded to OCEM, an Italian firm active in the field of electronic devices and power supplies, in collaboration with ENEA, for the manufacture and testing of all the diode stacks. In particular, CERN requests the measurement of the reverse and forward voltage diode characteristics at 300 K and 77 K, and endurance test cycles at liquid helium temperature. The experimental set-up at ENEA and data acquisition system developed for the scope will be described and the test results reported. (3 refs).

  5. Attend the lecture of the first artist-scientist inspiration partners of the Collide@CERN programme

    CERN Multimedia

    2012-01-01

    Julius Von Bismarck, the first winner of the Prix Ars Electronica Collide@CERN residency award for the digital arts and his science inspiration partner, Dr. James Wells, will present their individual work in art and science at the beginning of the residency on Wednesday 21 March at 18:45 at the Globe of Science and Innovation.   Hands up, this is a photo shoot! Julius Von Bismarck in action. All are welcome! The event will be in English, the common language between the artist and the scientist. To make a reservation for you and any guests, please send an e-mail to merce.monje.cano@cern.ch or call +41 22 76 75 246. For the complete programme of the event, see the official invitation.

  6. CERN-RD39 collaboration activities aimed at cryogenic silicon detector application in high-luminosity Large Hadron Collider

    Science.gov (United States)

    Li, Zheng; Eremin, Vladimir; Verbitskaya, Elena; Dehning, Bernd; Sapinski, Mariusz; Bartosik, Marcin R.; Alexopoulos, Andreas; Kurfürst, Christoph; Härkönen, Jaakko

    2016-07-01

    Beam Loss Monitors (BLM) made of silicon are new devices for monitoring of radiation environment in the vicinity of superconductive magnets of the Large Hadron Collider. The challenge of BLMs is extreme radiation hardness, up to 1016 protons/cm2 while placed in superfluid helium (temperature of 1.9 K). CERN BE-BI-BL group, together with CERN-RD39 collaboration, has developed prototypes of BLMs and investigated their device physics. An overview of this development-results of the in situ radiation tests of planar silicon detectors at 1.9 K, performed in 2012 and 2014-is presented. Our main finding is that silicon detectors survive under irradiation to 1×1016 p/cm2 at 1.9 K. In order to improve charge collection, current injection into the detector sensitive region (Current Injection Detector (CID)) was tested. The results indicate that the detector signal increases while operated in CID mode.

  7. Phenomenology of W plus or minus H plus or minus production at the CERN Large Handron Collider

    CERN Document Server

    Moretti, S

    1999-01-01

    Barrientos Bendezu' and Kniehl [hep-ph/9807480] recently suggested that $W^\\pm H^\\mp$ associated production may be a useful channel in the search for the elusive heavy charged Higgs bosons of the 2 Higgs Doublet Model at the Large Hadron Collider. We investigate the phenomenology of this mechanism in the Minimal Supersymmetric Standard Model, with special attention paid to the most likely heavy Higgs decay, $H^\\mp\\to tb\\to b\\bar b W^\\mp$, and to the irreducible background from top pair production. We find that the semi-leptonic signature `$b\\bar b W^+W^-\\to b\\bar b jj \\ell$ + missing momentum' is dominated by top-antitop events, which overwhelm the charged Higgs signal over the heavy mass range that can be probed at the CERN collider

  8. Probing small parton densities in ultraperipheral A A and pA collisions at the CERN large Hadron Collider.

    Science.gov (United States)

    Strikman, Mark; Vogt, Ramona; White, Sebastian

    2006-03-01

    We calculate photoproduction rates for several hard processes in ultraperipheral proton-lead and lead-lead collisions at the CERN Large Hadron Collider (LHC) with square root of sNN = 8.8 and 5.5 TeV, respectively, which could be triggered in the large LHC detectors. We use ATLAS as an example. The lead ion is treated as a source of (coherently produced) photons with energies and intensities greater than those of equivalent ep collisions at the DESY collider HERA. We find very large rates for both inclusive and diffractive production that will extend the HERA x range by nearly an order of magnitude for similar virtualities. We demonstrate that it is possible to reach the kinematic regime where nonlinear effects are larger than at HERA.

  9. LEP Dismantling: Wagons Roll!

    CERN Multimedia

    2001-01-01

    The first trucks transporting material from LEP and its four experiments left CERN on 31 January. Since the LEP dismantling operation began, the material had been waiting to be removed from the sites of the four experiments and the special transit area on the Prévessin site. On the evening of 30 January, the French customs authorities gave the green light for the transport operation to begin. So first thing the next day, the two companies in charge of recycling the material, Jaeger & Bosshard (Switzerland) and Excoffier (France), set to work. Only 1500 truckloads to go before everything has been removed!

  10. The LEP project

    CERN Document Server

    Southworth, Brian

    1981-01-01

    The Rutherford/Bohr concept of atomic structure was pleasingly simple but later research revealed a bewildering multiplicity of elementary particles. Recently, however, a 'new physics' has emerged according to which all these particles can be interpreted in terms of only four fundamental ones-two quarks and two leptons. To test this theory very powerful new machines are required, among the most important of which is the proposed electron-positron storage ring (LEP) at CERN. The design and development of LEP are described, with a brief outline of the project timetable. (5 refs).

  11. Physics Goals of the Next Century at CERN

    CERN Document Server

    Ellis, Jonathan Richard

    2000-01-01

    After recalling briefly the main physics issues beyond the Standard Model,the main physics objectives of experiments at CERN in the coming decade(s) arereviewed. These include the conclusion of the LEP programme during the year2000, a limited number of fixed-target experiments during the following years,the CNGS long-baseline neutrino programme and the LHC, both scheduled to startin 2005. Then possible accelerator projects at CERN after the LHC are reviewed,in the expectation that an $e^+ e^-$ linear collider in the TeV energy rangewill be built elsewhere. The default option for CERN's next major project maybe the CLIC multi-TeV $e^+ e^-$ collider project. Also interesting is theoption of a three-step scenario for muon storage rings, starting with aneutrino factory, continuing with one or more Higgs factories, and culminatingin a $\\mu^+ \\mu^-$ collider at the high-energy frontier.

  12. Physics goals of the next century at CERN

    International Nuclear Information System (INIS)

    After recalling briefly the main physics issues beyond the Standard Model, the main physics objectives of experiments at CERN in the coming decade(s) are reviewed. These include the conclusion of the LEP program during the year 2000, a limited number of fixed-target experiments during the following years, the CNGS long-baseline neutrino program and the LHC, both scheduled to start in 2005. Then possible accelerator projects at CERN after the LHC are reviewed, in the expectation that an e+e- linear collider in the TeV energy range will be built elsewhere. The default option for CERN's next major project may be the CLIC multi-TeV e+e- collider project. Also interesting is the option of a three-step scenario for muon storage rings, starting with a neutrino factory, continuing with one or more Higgs factories, and culminating in a μ+μ- collider at the high-energy frontier

  13. Uniform description of bulk observables in the hydrokinetic model of A+A collisions at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider

    Science.gov (United States)

    Karpenko, Iu. A.; Sinyukov, Yu. M.; Werner, K.

    2013-02-01

    A simultaneous description of hadronic yields; pion, kaon, and proton spectra; elliptic flows; and femtoscopy scales in the hydrokinetic model of A+A collisions is presented at different centralities for the top BNL Relativistic Heavy Ion Collider (RHIC) and CERN Large Hadron Collider (LHC) 2.76-TeV energies. The initial conditions are based on the Monte Carlo Glauber simulations. When going from RHIC to LHC energy in the model, the only parameters changed are the normalization of the initial entropy defined by the number of all charged particles in most central collisions, contribution to entropy from binary collisions, and barionic chemical potential. The hydrokinetic model is used in its hybrid version, which provides the correct match (at the isochronic hypersurface) of the decaying hadron matter evolution with hadronic ultrarelativistic quantum molecular dynamics cascade. The results are compared with the standard hybrid models where hydrodynamics and hadronic cascade are matching just at the non-space-like hypersurface of chemical freeze-out or on the isochronic hypersurface. The modification of the particle-number ratios at LHC caused, in particular, by the particle annihilations at the afterburn stage is also analyzed.

  14. Highlights from CERN: The CLIC Project for a Future e$^{+}$e$^{−}$ Linear Collider

    CERN Document Server

    Tecker, Frank

    2007-01-01

    A high luminosity ( 10$^{34}$-10$^{35}$ cm$^{2}$/s) linear electron-positron Collider (CLIC) with a nominal centre-of-mass energy of 3 TeV is under study in the framework of an international collaboration of laboratories and institutes, with the aim to provide the HEP community with a new facility for the post LHC era. After a brief introduction of the physics motivation, the CLIC scheme to extend Linear Colliders into the Multi-TeV colliding beam energy range will be described. In the following, the main challenges and the very promising achievements already obtained will be presented.

  15. Colliders

    CERN Document Server

    Chou, Weiren

    2014-01-01

    The idea of colliding two particle beams to fully exploit the energy of accelerated particles was first proposed by Rolf Wideröe, who in 1943 applied for a patent on the collider concept and was awarded the patent in 1953. The first three colliders — AdA in Italy, CBX in the US, and VEP-1 in the then Soviet Union — came to operation about 50 years ago in the mid-1960s. A number of other colliders followed. Over the past decades, colliders defined the energy frontier in particle physics. Different types of colliers — proton–proton, proton–antiproton, electron–positron, electron–proton, electron-ion and ion-ion colliders — have played complementary roles in fully mapping out the constituents and forces in the Standard Model (SM). We are now at a point where all predicted SM constituents of matter and forces have been found, and all the latest ones were found at colliders. Colliders also play a critical role in advancing beam physics, accelerator research and technology development. It is timel...

  16. Large Area Silicon Tracking Detectors with Fast Signal Readout for the Large Hadron Collider (LHC) at CERN

    CERN Document Server

    Köstner, S

    2005-01-01

    The Standard Model of elementary particles, which is summarized briefly in the second chapter, incorporates a number of successful theories to explain the nature and consistency of matter. However not all building blocks of this model could yet be tested by experiment. To confirm existing theories and to improve nowadays understanding of matter a new machine is currently being built at CERN, the Large Hadron Collider (LHC), described in the third chapter. LHC is a proton-proton collider which will reach unprecedented luminosities and center of mass energies. Five experiments are attached to it to give answers to questions like the existence of the Higgs meson, which allows to explain the mass content of matter, and the origin of CP-violation, which plays an important role in the baryogenesis of the universe. Supersymmetric theories, proposing a bosonic superpartner for each fermion and vice versa, will be tested. By colliding heavy ions, high energy and particle densities can be achieved and probed. This stat...

  17. Cern

    CERN Multimedia

    2009-01-01

    "La réparation de l'accélérateur géant de particules LHC, qui devrait redémarrer mi-novembre aprés une panne de plus d'un an, a coûté 23 millions d'euros, selon un haut responsable du Centre européen de recherche nucléaire (CERN), cité vendredi par les médias espagnols" (1 paragraph)

  18. Constraining the Higgs couplings to up and down quarks using production kinematics at the CERN Large Hadron Collider

    CERN Document Server

    Bonner, Gage

    2016-01-01

    We study the prospects for constraining the Higgs boson's couplings to up and down quarks using kinematic distributions in Higgs production at the CERN Large Hadron Collider. We find that the Higgs $p_T$ distribution can be used to constrain these couplings with precision competitive to other proposed techniques. With 3000 fb$^{-1}$ of data at 13 TeV in the four-lepton decay channel, we find $-0.73 \\lesssim \\bar{\\kappa}_u \\lesssim 0.33$ and $-0.88 \\lesssim \\bar{\\kappa}_d \\lesssim 0.32$, where $\\bar{\\kappa}_q = (m_q/m_b) \\kappa_q$ is a scaling factor that modifies the $q$ quark Yukawa coupling relative to the Standard Model bottom quark Yukawa coupling. The sensitivity may be improved by including additional Higgs decay channels.

  19. Study of some optical glues for the Compact Muon Solenoid at the Large Hadron Collider of CERN

    CERN Document Server

    Montecchi, Marco

    2001-01-01

    Two Avalanche Photodiodes will measure the light produced in each of the 61,200 PbWO4 crystals composing the barrel part of the electromagnetic calorimeter of the Compact Muon Solenoid (CMS) at the Large Hadron Collider of CERN. To improve the collection of the photons, these detectors will be glued to the crystal. To be used in CMS, the optical glue must fulfil several requirements. The paper describes those requirements and reports the results of the investigation of several commercial optical glues. In particular, refractive index, absorption length, radiation hardness and forecast ageing after 15 years are reported. The most promising glue for CMS was more deeply investigated, in particular its chemical composition, chemical compatibility with the other parts of the calorimeter and curing time in realistic conditions.

  20. Calculation of abort thresholds for the Beam Loss Monitoring System of the Large Hadron Collider at CERN

    CERN Document Server

    Nemcic, Martin; Dehning, Bernd

    The Beam Loss Monitoring (BLM) System is one of the most critical machine protection systems for the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN), Switzerland. Its main purpose is to protect the superconducting magnets from quenches and other equipment from damage by requesting a beam abort when the measured losses exceed any of the predefined threshold levels. The system consist of circa 4000 ionization chambers which are installed around the 27 kilometres ring (LHC). This study aims to choose a technical platform and produce a system that addresses all of the limitations with the current system that is used for the calculation of the LHC BLM abort threshold values. To achieve this, a comparison and benchmarking of the Java and .NET technical platforms is performed in order to establish the most suitable solution. To establish which technical platform is a successful replacement of the current abort threshold calculator, comparable prototype systems in Java and .NET we...

  1. Simulation study of electron cloud induced instabilities and emittance growth for the CERN Large Hadron Collider proton beam

    CERN Document Server

    Benedetto, Elena; Schulte, Daniel; Rumolo, Giovanni

    2005-01-01

    The electron cloud may cause transverse single-bunch instabilities of proton beams such as those in the Large Hadron Collider (LHC) and the CERN Super Proton Synchrotron (SPS). We simulate these instabilities and the consequent emittance growth with the code HEADTAIL, which models the turn-by-turn interaction between the cloud and the beam. Recently some new features were added to the code, in particular, electric conducting boundary conditions at the chamber wall, transverse feedback, and variable beta functions. The sensitivity to several numerical parameters has been studied by varying the number of interaction points between the bunch and the cloud, the phase advance between them, and the number of macroparticles used to represent the protons and the electrons. We present simulation results for both LHC at injection and SPS with LHC-type beam, for different electron-cloud density levels, chromaticities, and bunch intensities. Two regimes with qualitatively different emittance growth are observed: above th...

  2. slice of a LEP bending magnet

    CERN Multimedia

    This is a slice of a LEP dipole bending magnet, made as a concrete and iron sandwich The bending field needed in LEP is small (about 1000 Gauss), equivalent to two of the magnets people stick on fridge doors. Because it is very difficult to keep a low field steady, a high field was used in iron plates embedded in concrete. A CERN breakthrough in magnet design, LEP dipoles can be tuned easily and are cheaper than conventional magnets.

  3. Slice of a LEP bending magnet

    CERN Multimedia

    This is a slice of a LEP dipole bending magnet, made as a concrete and iron sandwich. The bending field needed in LEP is small (about 1000 Gauss), equivalent to two of the magnets people stick on fridge doors. Because it is very difficult to keep a low field steady, a high field was used in iron plates embedded in concrete. A CERN breakthrough in magnet design, LEP dipoles can be tuned easily and are cheaper than conventional magnets.

  4. Ceremony to mark the installation of first magnet at LEP

    CERN Multimedia

    CERN Audiovisual Team

    1987-01-01

    Speech from French Prime Minister Jacques Chirac following the installation of the first magnet at LEP on 4 June 1987. And from Herwig Schopper, CERN Director-General; Swiss President Pierre Aubert and Wolfgang Kummer, President of the CERN Council.

  5. Beam dynamics aspects of crab cavities in the CERN Large Hadron Collider

    CERN Document Server

    Sun, Y P; Barranco, J; Tomás, R; Weiler, T; Zimmermann, F; Calaga, R; Morita, A

    2009-01-01

    Modern colliders bring into collision a large number of bunches to achieve a high luminosity. The long-range beam-beam effects arising from parasitic encounters at such colliders are mitigated by introducing a crossing angle. Under these conditions, crab cavities (CC) can be used to restore effective head-on collisions and thereby to increase the geometric luminosity. Such crab cavities have been proposed for both linear and circular colliders. The crab cavities are rf cavities operated in a transverse dipole mode, which imparts on the beam particles a transverse kick that varies with the longitudinal position along the bunch. The use of crab cavities in the Large Hadron Collider (LHC) may not only raise the luminosity, but it could also complicate the beam dynamics, e.g., crab cavities might not only cancel synchrobetatron resonances excited by the crossing angle but they could also excite new ones, they could reduce the dynamic aperture for off-momentum particles, they could influence the aperture and orbit...

  6. Who cares about particle physics? making sense of the Higgs boson, the Large Hadron Collider and CERN

    CERN Document Server

    AUTHOR|(CDS)2051327

    2016-01-01

    CERN, the European Laboratory for particle physics, regularly makes the news. What kind of research happens at this international laboratory and how does it impact people's daily lives? Why is the discovery of the Higgs boson so important? Particle physics describes all matter found on Earth, in stars and all galaxies but it also tries to go beyond what is known to describe dark matter, a form of matter five times more prevalent than the known, regular matter. How do we know this mysterious dark matter exists and is there a chance it will be discovered soon? About sixty countries contributed to the construction of the gigantic Large Hadron Collider (LHC) at CERN and its immense detectors. Dive in to discover how international teams of researchers work together to push scientific knowledge forward. Here is a book written for every person who wishes to learn a little more about particle physics, without requiring prior scientific knowledge. It starts from the basics to build a solid understanding of current res...

  7. Physics of Z0/γ*-tagged jets at energies available at the CERN Large Hadron Collider

    International Nuclear Information System (INIS)

    Electroweak bosons produced in conjunction with jets in high-energy collider experiments is one of the principal final-state channels that can be used to test the accuracy of perturbative quantum chromodynamics calculations and to assess the potential to uncover new physics through comparison between data and theory. In this article we present results for the Z0/γ*+jet production cross sections at the CERN Large Hadron Collider (LHC) at leading and next-to-leading orders. In proton-proton reactions we elucidate up to O(GFαs2) the constraints that jet tagging via the Z0/γ* decay dileptons provides on the momentum distribution of jets. In nucleus-nucleus reactions we demonstrate that tagged jets can probe important aspects of the dynamics of quark and gluon propagation in hot and dense nuclear matter and characterize the properties of the medium-induced parton showers in ways not possible with more inclusive measurements. Finally, we present specific predictions for the anticipated suppression of the Z0/γ*+jet production cross section in the quark-gluon plasma that is expected to be created in central lead-lead collisions at the LHC relative to the naive superposition of independent nucleon-nucleon scatterings.

  8. Development of large-capacity refrigeration at 1.8 K for the Large Hadron Collider at CERN

    CERN Document Server

    Lebrun, P; Claudet, G

    1996-01-01

    CERN, the European Laboratory for Particle Physics, is working towards the construction of the Large Hadron Collider (LHC), a high-energy, high-luminosity particle accelerator and collider [1] of 26.7 km circumference, due to start producing frontier physics, by bringing into collision intense proton and ion beams with centre-of-mass energies in the TeV-per-constituent range, at the beginning of the next century. The key technology for achieving this ambitious scientific goal at economically acceptable cost is the use of high-field superconducting magnets using Nb-Ti conductor operating in superfluid helium [2]. To maintain the some 25 km of bending and focusing magnets at their operating temperature of 1.9 K, the LHC cryogenic system will have to produce an unprecedented total refrigeration capacity of about 20 kW at 1.8 K, in eight cryogenic plants distributed around the machine circumference [3]. This has requested the undertaking of an industrial development programme, in the form of a collaboration betwe...

  9. Physics at Future Colliders

    OpenAIRE

    Ellis, John

    1997-01-01

    After a brief review of the Big Issues in particle physics, we discuss the contributions to resolving that could be made by various planned and proposed future colliders. These include future runs of LEP and the Fermilab Tevatron collider, B factories, RHIC, the LHC, a linear electron-positron collider, an electron-proton collider in the LEP/LHC tunnel, a muon collider and a future larger hadron collider (FLHC). The Higgs boson and supersymmetry are used as benchmarks for assessing their capa...

  10. CERN/KEK: Very high accelerating gradients

    International Nuclear Information System (INIS)

    Full text: A world-wide effort is under way to develop linear electron-positron colliders so that physics experiments can be extended into a range of energies where circular machines (necessarily much larger than CERN's 27-kilometre LEP machine) would be crippled by synchrotron radiation. CERN is studying the feasibility of building a 2 TeV machine called CLIC powered not by individual klystrons, but by a high intensity electron 'drive' linac running parallel to the main linac (November 1990, page 7). This drive linac will itself be powered by similar superconducting cavities to those developed for LEP. A high gradient is an obvious design aim for any future high energy linear collider because it makes it shorter and therefore cheaper - the design figure for the CLIC machine is 80 MV/m. The CLIC study group has taken a significant step forward in demonstrating the technical feasibility of their machine by achieving peak and average accelerating gradients of 137 MV/m and 84 MV/m respectively in a short section of accelerating structure during high gradient tests at the Japanese KEK Laboratory last year. This result obtained within the framework of a CERN/KEK collaboration on linear colliders was obtained using a 20-cell accelerating section built at CERN using state-of the- art technology which served both as a model for CLIC studies as well as a prototype for the Japanese Linear Collider studies. The operating frequency of the model accelerating section is 2.6 times lower than the CLIC frequency but was chosen because a high power r.f. source and pulse compression scheme has been developed for this frequency at KEK. Testing CLIC models at 11.4 GHz is however more stringent than at 30 GHz because the chance of electrical breakdown increases as the frequency is lowered. This recent result clearly demonstrates that a gradient of 80 MV/m is feasible

  11. LEP - ppbar

    CERN Multimedia

    CERN ???

    1983-01-01

    Aerial views. UA1, big rectangle of metal going down to the detector. E. Jones, ACOL control room, filled with people (a first?). See ACOL. Chantier, LEP shaft. Underground. LEP dipole magnet construction. Interview with Schopper and LEP: history has shown that the discovery of new phenomena has led to new applications...."I don't have the imagination to predict what could come out from the research we are doing now," but history has shown...electro-magnetism led to radio, tv. Comments : colour washed out, green. Silent at beginning and from time to time after

  12. Evidence of subnucleonic degrees of freedom in J /ψ photoproduction in ultraperipheral collisions at energies available at the CERN Large Hadron Collider

    Science.gov (United States)

    Andrade-II, E.; González, I.; Deppman, A.; Bertulani, C. A.

    2015-12-01

    We present calculations for the incoherent photoproduction of J /ψ vector mesons in ultraperipheral heavy ion collisions (UPCs) in terms of hadronic interactions. This study was carried out using the recently developed Monte Carlo model CRISP extended to include UPCs at energies available at the CERN Large Hadron Collider. A careful study of rescattering and destruction of the J /ψ particles is presented for Pb + Pb collisions at √{sN N}=2.76 TeV. We have also compared our method to Au + Au collisions at √{sN N}=200 GeV measured at the BNL Relativistic Heavy Ion Collider.

  13. Britain's delegation to CERN, the European Centre for Nuclear Research near Geneva, voted in favour of a project which take seven years to build, involve a 27 kilometre long tunnel, and cost 230 million pounds. Now LEP receives the go-ahead later this month

    CERN Multimedia

    Llewellyn Smith, Christopher Hubert

    1981-01-01

    Britain's delegation to CERN, the European Centre for Nuclear Research near Geneva, voted in favour of a project which take seven years to build, involve a 27 kilometre long tunnel, and cost 230 million pounds. Now LEP receives the go-ahead later this month

  14. Et. réact. $e^{+} e^{-} \\to e^{+} e^{-} \\gamma$, $e^{+} e^{-} \\to e^{+} e^{-} e^{+} e^{-}$ et $e^{+} e^{-} \\to e^{+} e ^{-} \\mu^{+} \\mu^{-}$ pour la calibrat. cristaux BGO calorim. électromagn. L3,, CERN, mesure luminosité LEP

    CERN Document Server

    Rayo, F

    1989-01-01

    Et. réact. $e^{+} e^{-} \\to e^{+} e^{-} \\gamma$, $e^{+} e^{-} \\to e^{+} e^{-} e^{+} e^{-}$ et $e^{+} e^{-} \\to e^{+} e ^{-} \\mu^{+} \\mu^{-}$ pour la calibrat. cristaux BGO calorim. électromagn. L3,, CERN, mesure luminosité LEP

  15. CERN Library | Arthur I. Miller presents "Colliding worlds: How Cutting-Edge Science Is Redefining Contemporary Art" | 21 October

    CERN Multimedia

    2014-01-01

    In recent decades, an exciting new art movement has emerged in which artists illuminate the latest advances in science.   Some of their provocative creations - a live rabbit implanted with the fluorescent gene of a jellyfish, a gigantic glass-and-chrome sculpture of the Big Bang itself - can be seen in traditional art museums and magazines, while others are being made by leading designers at Pixar, Google's Creative Lab and the MIT Media Lab. Arthur I. Miller takes readers on a wild journey to explore this new frontier. From the movement's origins a century ago - when Einstein shaped Cubism and X-rays affected fine photography - to the latest discoveries of biotechnology, cosmology and quantum physics, Miller shows how today's artists and designers are producing work at the cutting edge of science. Tuesday, 21 October 2014 at 14:30 in the Library, Bldg. 52 1-052 https://indico.cern.ch/event/346299/ *Coffee will be served from 2 p.m.* "Colliding Worlds: How Cutt...

  16. Sources of machine-induced background in the ATLAS and CMS detectors at the CERN Large Hadron Collider

    CERN Document Server

    Bruce, R; Boccone, V; Bregliozzi, G; Burkhardt, H; Cerutti, F; Ferrari, A; Huhtinen, M; Lechner, A; Levinsen, Y; Mereghetti, A; Mokhov, N V; Tropin, I S; Vlachoudis, V

    2013-01-01

    One source of experimental background in the CERN Large Hadron Collider (LHC) is particles entering the detectors from the machine. These particles are created in cascades, caused by upstream interactions of beam protons with residual gas molecules or collimators. We estimate the losses on the collimators with SixTrack and simulate the showers with FLUKA and MARS to obtain the flux and distribution of particles entering the ATLAS and CMS detectors. We consider some machine configurations used in the first LHC run, with focus on 3.5 TeV operation as in 2011. Results from FLUKA and MARS are compared and a very good agreement is found. An analysis of logged LHC data provides, for different processes, absolute beam loss rates, which are used together with further simulations of vacuum conditions to normalize the results to rates of particles entering the detectors. We assess the relative importance of background from elastic and inelastic beam-gas interactions, and the leakage out of the LHC collimation system, a...

  17. Temperature dependent formation-time approach for $\\Upsilon$ suppression at energies available at the CERN Large Hadraon Collider

    CERN Document Server

    Ganesh, S

    2015-01-01

    We present here a comprehensive model to describe the bottomonium suppression data obtained from the CERN Large Hadron Collider (LHC) at center-of-mass energy of $\\sqrt{s_{NN}}=2.76$ TeV. We employ a quasiparticle model (QPM) equation of state for the quark-gluon plasma (QGP) expanding under Bjorken's scaling law. The current model includes the modification of the formation time based on the temperature of the QGP, color screening during bottomonium production, gluon induced dissociation and collisional damping due to the imaginary part of the potential between the $b\\bar b$ pair. We propose a method for determining the temperature-dependent formation time of bottomonia using the solution of the time-independent Schr\\"{o}dinger equation and compare it with another approach based on time-dependent Schr\\"{o}dinger wave equation simulation. We find that these two independent methods based on different axioms give similar results for the formation time. Cold nuclear matter effects and feed-down from higher resona...

  18. Light-by-light scattering in ultraperipheral Pb-Pb collisions at energies available at the CERN Large Hadron Collider

    Science.gov (United States)

    Kłusek-Gawenda, Mariola; Lebiedowicz, Piotr; Szczurek, Antoni

    2016-04-01

    We calculate cross sections for diphoton production in (semi)exclusive PbPb collisions, relevant for the CERN Large Hadron Collider (LHC). The calculation is based on the equivalent photon approximation in the impact parameter space. The cross sections for the elementary γ γ →γ γ subprocess are calculated including two different mechanisms. We take into account box diagrams with leptons and quarks in the loops. In addition, we consider a vector-meson dominance (VDM-Regge) contribution with virtual intermediate hadronic (vector-like) excitations of the photons. We get measurable cross sections in PbPb collisions. This opens a possibility to study the γ γ →γ γ (quasi)elastic scattering at the LHC. We present many interesting differential distributions which could be measured by the ALICE, CMS, or ATLAS Collaborations at the LHC. We study whether a separation or identification of different components (boxes, VDM-Regge) is possible. We find that the cross section for elastic γ γ scattering could be measured in the heavy-ion collisions for subprocess energies smaller than Wγ γ≈15 -20 GeV.

  19. Sources of machine-induced background in the ATLAS and CMS detectors at the CERN Large Hadron Collider

    Energy Technology Data Exchange (ETDEWEB)

    Bruce, R.; et al.,

    2013-11-21

    One source of experimental background in the CERN Large Hadron Collider (LHC) is particles entering the detectors from the machine. These particles are created in cascades, caused by upstream interactions of beam protons with residual gas molecules or collimators. We estimate the losses on the collimators with SixTrack and simulate the showers with FLUKA and MARS to obtain the flux and distribution of particles entering the ATLAS and CMS detectors. We consider some machine configurations used in the first LHC run, with focus on 3.5 TeV operation as in 2011. Results from FLUKA and MARS are compared and a very good agreement is found. An analysis of logged LHC data provides, for different processes, absolute beam loss rates, which are used together with further simulations of vacuum conditions to normalize the results to rates of particles entering the detectors. We assess the relative importance of background from elastic and inelastic beam-gas interactions, and the leakage out of the LHC collimation system, and show that beam-gas interactions are the dominating source of machine-induced background for the studied machine scenarios. Our results serve as a starting point for the experiments to perform further simulations in order to estimate the resulting signals in the detectors.

  20. Installation of first magnet at LEP

    CERN Multimedia

    1987-01-01

    Speech by French Prime Minister Jacques Chirac following the installation of the first magnet at LEP on 4 June 1987. From left to right: Herwig Schopper, CERN Director-General; Jacques Chirac; Swiss President Pierre Aubert and Wolfgang Kummer, President of the CERN Council.

  1. Proposal for the donation of LEP equipment

    CERN Document Server

    2000-01-01

    CERN has announced that LEP equipment will become available for donations to educational and scientific research institutes, to museums and public bodies in Member States and non-member States. A number of requests for a limited amount of equipment have been received. CERN has no further use for this equipment. The Finance Committee is invited to approve these donations.

  2. The original LEP machine Exhibition LEPFest 2000

    CERN Multimedia

    2000-01-01

    With a circumference of 27 kilometres,LEP is the largest particle collider in the world.At about 100 metres underground,bunches of electrons and positrons race around in opposite directions as they are accelerated to almost the speed of light.In its first phase of operation,LEP was designed to collide electrons and positrons at an energy of around 100 GeV.After accumulating data on the decay of the Z particle -electrically neutral messenger of the weak force with a mass of 91.2 GeV -everything was done to boost the energy of LEP 's particle beams as high as possible.

  3. Novel Concepts for Optimization of the CERN Large Hadron Collider Injection Lines.

    CERN Document Server

    Fuchsberger, Kajetan; Wenninger, J

    2011-01-01

    The Large Hadron Collider (LHC) is presently the particle accelerator with the highest center of mass energy in the world and is for that reason the most promising instrument for particle physics discoveries in the near future. The transfer lines TI2 and TI8 which transfer the beam from the last pre-accelerator, the Super Proton Synchrotron (SPS), to the LHC are with a total length of about 6 km the longest ones in the world, which makes it necessary to do optics matching with high precision. Tests between 2004 and 2008 revealed several, previousely unpredicted, effects in these lines: An assymetry in betatron phase between the two transverse planes, a dispersion mismatch at the injection point from the transfer lines to the LHC and unexpectedly strong transverse coupling at the same location. In this thesis, we introduce the methods and tools that we developed to investigate these discrepancies. We describe the analysis of the available data, measurements of the transfer line optics and the calculation of op...

  4. Reliability of the Beam Loss Monitors System for the Large Hadron Collider at CERN

    CERN Document Server

    Guaglio, G; Santoni, C

    2005-01-01

    The energy stored in the Large Hadron Collider is unprecedented. The impact of the beam particles can cause severe damage on the superconductive magnets, resulting in significant downtime for repairing. The Beam Loss Monitors System (BLMS) detects the secondary particles shower of the lost beam particles and initiates the extraction of the beam before any serious damage to the equipment can occur. This thesis defines the BLMS specifications in term of reliability. The main goal is the design of a system minimizing both the probability to not detect a dangerous loss and the number of false alarms generated. The reliability theory and techniques utilized are described. The prediction of the hazard rates, the testing procedures, the Failure Modes Effects and Criticalities Analysis and the Fault Tree Analysis have been used to provide an estimation of the probability to damage a magnet, of the number of false alarms and of the number of generated warnings. The weakest components in the BLMS have been pointed out....

  5. Precision Experiments at LEP

    CERN Document Server

    de Boer, Wim

    2015-01-01

    The Large Electron Positron Collider (LEP) established the Standard Model (SM) of particle physics with unprecedented precision, including all its radiative corrections. These led to predictions for the masses of the top quark and Higgs boson, which were beautifully confirmed later on. After these precision measurements the Nobel Prize in Physics was awarded in 1999 jointly to 't Hooft and Veltman "for elucidating the quantum structure of electroweak interactions in physics". Another hallmark of the LEP results were the precise measurements of the gauge coupling constants, which excluded unification of the forces within the SM, but allowed unification within the supersymmetric extension of the SM. This increased the interest in Supersymmetry (SUSY) and Grand Unified Theories, especially since the SM has no candidate for the elusive dark matter, while Supersymmetry provides an excellent candidate for dark matter. In addition, Supersymmetry removes the quadratic divergencies of the SM and {\\it predicts} the Hig...

  6. High accuracy magnetic field mapping of the LEP spectrometer magnet

    CERN Document Server

    Roncarolo, F

    2000-01-01

    The Large Electron Positron accelerator (LEP) is a storage ring which has been operated since 1989 at the European Laboratory for Particle Physics (CERN), located in the Geneva area. It is intended to experimentally verify the Standard Model theory and in particular to detect with high accuracy the mass of the electro-weak force bosons. Electrons and positrons are accelerated inside the LEP ring in opposite directions and forced to collide at four locations, once they reach an energy high enough for the experimental purposes. During head-to-head collisions the leptons loose all their energy and a huge amount of energy is concentrated in a small region. In this condition the energy is quickly converted in other particles which tend to go away from the interaction point. The higher the energy of the leptons before the collisions, the higher the mass of the particles that can escape. At LEP four large experimental detectors are accommodated. All detectors are multi purpose detectors covering a solid angle of alm...

  7. Reliability of the beam loss monitors system for the large hadron collider at CERN

    International Nuclear Information System (INIS)

    The energy stored in the Large Hadron Collider is unprecedented. The impact of the beam particles can cause severe damage on the superconductive magnets, resulting in significant downtime for repairing. The Beam Loss Monitors System (BLMS) detects the secondary particles shower of the lost beam particles and initiates the extraction of the beam before any serious damage to the equipment can occur. This thesis defines the BLMS specifications in term of reliability. The main goal is the design of a system minimizing both the probability to not detect a dangerous loss and the number of false alarms generated. The reliability theory and techniques utilized are described. The prediction of the hazard rates, the testing procedures, the Failure Modes Effects and Criticalities Analysis and the Fault Tree Analysis have been used to provide an estimation of the probability to damage a magnet, of the number of false alarms and of the number of generated warnings. The weakest components in the BLMS have been pointed out. The reliability figures of the BLMS have been calculated using a commercial software package (Isograph.). The effect of the variation of the parameters on the obtained results has been evaluated with a sensitivity analysis. The reliability model has been extended by the results of radiation tests. Design improvements, like redundant optical transmission, have been implemented in an iterative process. The proposed system is compliant with the reliability requirements. The model uncertainties are given by the limited knowledge of the thresholds levels of the superconductive magnets and of the locations of the losses along the ring. The implemented model allows modifications of the system, following the measuring of the hazard rates during the LHC life. It can also provide reference numbers to other accelerators which will implement similar technologies. (author)

  8. Experience with the LEP Superconducting RF Accelerating System

    CERN Document Server

    Geschonke, Günther

    1998-01-01

    CERN is presently upgrading the large Electron Positron Collider (LEP) to higher energy by installing superconducting RF accelerating cavities. For a total installed circumferential voltage of about 2800 MV, 272 cavities operating at 352 MHz will be needed, representing an active length of 462 m and a cold surface of more than 1600 m2. The series production cavities are made out of copper, sputter-coated with a thin layer of niobium and cooled with liquid He to 4.5 K. The cavities are produced by industry and the acceptance testing is done at CERN. In 1996, 176 cavities had been installed and run successfully at their design gradient of 6 MV/m during physics at a beam energy of 86 GeV. As RF power sources 36 klystrons will finally be installed with a nominal RF output power of 1 MW each. In this paper the superconducting accelerating system in LEP will be described and experience gained during operation for physics as well as new developments will be presented.

  9. CERN: Fixed target targets

    International Nuclear Information System (INIS)

    Full text: While the immediate priority of CERN's research programme is to exploit to the full the world's largest accelerator, the LEP electron-positron collider and its concomitant LEP200 energy upgrade (January, page 1), CERN is also mindful of its long tradition of diversified research. Away from LEP and preparations for the LHC proton-proton collider to be built above LEP in the same 27-kilometre tunnel, CERN is also preparing for a new generation of heavy ion experiments using a new source, providing heavier ions (April 1992, page 8), with first physics expected next year. CERN's smallest accelerator, the LEAR Low Energy Antiproton Ring continues to cover a wide range of research topics, and saw a record number of hours of operation in 1992. The new ISOLDE on-line isotope separator was inaugurated last year (July, page 5) and physics is already underway. The remaining effort concentrates around fixed target experiments at the SPS synchrotron, which formed the main thrust of CERN's research during the late 1970s. With the SPS and LEAR now approaching middle age, their research future was extensively studied last year. Broadly, a vigorous SPS programme looks assured until at least the end of 1995. Decisions for the longer term future of the West Experimental Area of the SPS will have to take into account the heavy demand for test beams from work towards experiments at big colliders, both at CERN and elsewhere. The North Experimental Area is the scene of larger experiments with longer lead times. Several more years of LEAR exploitation are already in the pipeline, but for the longer term, the ambitious Superlear project for a superconducting ring (January 1992, page 7) did not catch on. Neutrino physics has a long tradition at CERN, and this continues with the preparations for two major projects, the Chorus and Nomad experiments (November 1991, page 7), to start next year in the West Area. Delicate neutrino oscillation effects could become

  10. The DELPHI distributed information system for exchanging LEP machine related information

    Science.gov (United States)

    Dönszelmann, M.; Gaspar, C.

    1994-12-01

    An information management system was designed and implemented to interchange information between the DELPHI experiment at CERN and the monitoring/control system for the LEP (Large Electron Positron Collider) accelerator. This system is distributed and communicates with many different sources and destinations (LEP) using different types of communication. The system itself communicates internally via a communication system based on a publish-and-subscribe mechanism, DIM (Distributed Information Manager). The information gathered by this system is used for on-line as well as off-line data analysis. Therefore it logs the information to a database and makes it available to operators and users via DUI (DELPHI User Interface). The latter was extended to be capable of displaying "time-evolution" plots. It also handles a protocol, implemented using a finite state machine, SMI (State Management Interface), for (semi-)automatic running of the Data Acquisition System and the Slow Controls System.

  11. Monitoring the waste water of LEP

    CERN Document Server

    Rühl, I

    1999-01-01

    Along the LEP sites CERN is discharging water of differing quality and varying amounts into the local rivers. This wastewater is not only process water from different cooling circuits but also water that infiltrates into the LEP tunnel. The quality of the discharged wastewater has to conform to the local environmental legislation of our Host States and therefore has to be monitored constantly. The most difficult aspect regarding the wastewater concerns LEP Point 8 owing to an infiltration of crude oil (petroleum), which is naturally contained in the soil along octant 7-8 of the LEP tunnel. This paper will give a short summary of the modifications made to the oil/water separation unit at LEP Point 8. The aim was to obtain a satisfactory oil/water separation and to install a monitoring system for a permanent measurement of the amount of hydrocarbons in the wastewater.

  12. The design and construction of a double-sided Silicon Microvertex Detector for the L3 experiment at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Adam, A. [Technical Univ., Budapest (Hungary). Physical Inst.; Ahlen, S.; Marin, A.; Zhou, B. [Boston Univ., MA (United States); Ambrosi, G.; Babucci, E.; Bertucci, B.; Biasini, M.; Bilei, G.M.; Caria, M.; Checcucci, B.; Easo, S.; Fiandrini, E.; Krastev, V.R.; Massetti, R.; Pauluzzi, M.; Santocchia, A.; Servoli, L. [INFN/Universita di Perugia (Italy); Baschirotto, A.; Bosetti, M.; Pensotti, S.; Rancoita, P.G.; Rattaggi, M.; Terzi, G. [INFN/Universita di Milano (Italy); Battiston, R. [CERN, Geneva (Switzerland)]|[INFN/Universita di Perugia (Italy); Bay, A.; Burger, W.J.; Extermann, P.; Perrin, E.; Susinno, G.F. [Univ. of Geneva (Switzerland); Bencze, G.Y.L.; Kornis, J.; Toth, J. [KFKI/Research Inst. for Particle and Nuclear Physics, Budapest (Hungary); Bobbink, G.J.; Duinker, P. [NIKHEF, Amsterdam (Netherlands); Brooks, M.L.; Coan, T.E.; Kapustinsky, J.S.; Kinnison, W.W.; Lee, D.M.; Mills, G.B.; Thompson, T.C. [Los Alamos National Lab., NM (United States); Busenitz, J.; DiBitonto, D. [Univ. of Alabama, Tuscaloosa, AL (United States); Camps, C.; Commichau, V.; Hangartner, K.; Schmitz, P. [RWTH, Aachen (Germany). 3. Physikalisches Institut; Castellini, G. [INFN/IROE, Firenze (Italy); Chen, A.; Hou, S.; Lin, W.T. [NCU, Chung/Li (Taiwan, Province of China); Gougas, A.; Kim, D.; Paul, T. [Johns Hopkins Univ., Baltimore, MD (United States); Hauviller, C.; Herve, A.; Josa, I. [CERN, Geneva (Switzerland); Landi, G. [INFN/Universita di Firenze (Italy); Lebeau, M. [LAPP, Annecy (France); Lecomte, P.; Viertel, G.M.; Waldmeier, S. [ETH Zurich (Switzerland); Leiste, R. [CERN, Geneva (Switzerland)]|[DESY-IFH, Zeuthen (Germany); Lejeune, E.; Weill, R. [Univ. of Lausanne (Switzerland); Lohmann, W.; Nowak, H.; Sachwitz, M.; Schoeniech, B.; Tonisch, F.; Trowitzsch, G.; Vogt, H. [DESY-IFH, Zeuthen (Germany); Passaleva, G. [INFN/Universita di Firenze (Italy)]|[INFN/Universita di Perugia (Italy); Yeh, S.C. [National Tsing Hua Univ., Hsinchu (Taiwan)

    1993-12-01

    A Silicon Microvertex Detector (SMD) has been commissioned for the L3 experiment at the Large Electron-Positron colliding-beam accelerator (LEP) at the European Center for Nuclear Physics, (CERN). The SMD is a 72,672 channel, two layer barrel tracker that is comprised of 96 ac-coupled, double-sided silicon detectors. Details of the design and construction are presented.

  13. The design and construction of a double-sided Silicon Microvertex Detector for the L3 experiment at CERN

    International Nuclear Information System (INIS)

    A Silicon Microvertex Detector (SMD) has been commissioned for the L3 experiment at the Large Electron-Positron colliding-beam accelerator (LEP) at the European Center for Nuclear Physics, (CERN). The SMD is a 72,672 channel, two layer barrel tracker that is comprised of 96 ac-coupled, double-sided silicon detectors. Details of the design and construction are presented

  14. LEP Radio Frequency Copper Cavities

    CERN Multimedia

    The pulse of a particle accelerator. 128 of these radio frequency cavities were positioned around CERN's 27-kilometre LEP ring to accelerate electrons and positrons. The acceleration was produced by microwave electric oscillations at 352 MHz. The electrons and positrons were grouped into bunches, like beads on a string, and the copper sphere at the top stored the microwave energy between the passage of individual bunches. This made for valuable energy savings as it reduced the heat generated in the cavity.

  15. Inauguration LEP

    CERN Document Server

    Schopper,H; Janis

    1983-01-01

    Le DG H.Schopper salue le président de la république française, F.Mitterand, le président de la confédaration suisse P.Aubert, ainsi que les ministres et représentants du gouvernement des 12 états membres pour la célébration et inauguration du LEP.

  16. Inside the LEP control room at start-up

    CERN Multimedia

    1989-01-01

    Physicists grouped around a screen in the LEP control room at the strat-up of LEP on 14 July 1989. The emotion of the moment is clear. Carlo Rubbia, Director-General of CERN at the time, is in the centre and on his left, Herwig Schopper, former Director-General of the Organization.

  17. LEP Electroweak and QCD Exhibition Lepton-Photon 2001

    CERN Multimedia

    2001-01-01

    The LEP collider an at centre-of-mass energies around the Z mass from 1989 to 1995 (LEP1).F om 1995 to 2000 (LEP2),the energy was gradually increased, crossing the W-pair production threshold in 1996,and eaching 208 GeV in 2000. Each of the four experiments,ALEPH,DELPHI,L3 and OPAL,observed around 4.5 million Z and 12 thousand W-pair events.

  18. The vacuum chamber in the interaction region of particle colliders a historical study and developments implementations in the LHCb experiment at CERN

    CERN Document Server

    Knaster, J R; Gamez-Mejias, L

    2004-01-01

    The history of particle colliders begins in the early 60's when an idea previously patented by R. Wideroe in 1953 is constructed. The design of the vacuum chamber in their experimental area became essential as it was the rst physical barrier that the particles to be detected needed to traverse. The interaction of the products of the collisions with the vacuum chamber structural materials, hindered the identification of the significative events. This Thesis analyses the historical evolution of the experimental vacuum chambers and summarizes the technical criteria that are to be fulfilled. The Large Hadron Collider (LHC) presently under construction at CERN is the last generation of particle colliders. Four big experiments will be in operation (ATLAS, CMS, ALICE and LHCb) in the LHC with diferent physics objectives. In particular, LHCb will be devoted to the study of CP violation and the design of its vacuum chamber is the scope of this Thesis. Physics simulations with an initial design consisting of a conical ...

  19. CERN looks to the long-term future: might a 100km circular collider follow the LHC around mid-century?

    CERN Document Server

    CERN. Geneva

    2015-01-01

    Particle physics is a long-term field of research: the LHC was originally conceived in the 1980s, but did not start running until 25 years later. An accelerator unlike any other, it is now just at the start of a programme that is set to run for another 20 years. While the LHC programme is already well defined for the next two decades, it is now time to look even further ahead, and so CERN is initiating an exploratory study for a future long-term project centred on a next-generation circular collider with a circumference of 80 to 100 kilometres. A worthy successor to the LHC, whose collision energies will reach 13 TeV in 2015, such an accelerator would allow particle physicists to push the boundaries of knowledge even further. The Future Circular Collider (FCC) programme will focus on studies for a hadron collider, like the LHC, capable of reaching unprecedented energies in the region of 100 TeV. It will also study electron-positron and electron-proton options. Opening with an introduction to the LHC and its...

  20. Deformation analysis of LEP

    International Nuclear Information System (INIS)

    LEP (Large Electron Positron Collider) is in an underground accelerator, located in a tunnel of 27 km circumference and from 40 to 160 m deep. It is the largest accelerator in the world. The electrons and positrons circulate in opposite directions and hit each other in four points. The collisions are observed by means of detectors, housed in large underground caverns. Due to the sensitivity of such accelerators to alignment errors a complete leveling is made every year, followed by a 'smoothing' process - i.e. an optimal refinement of successive positions - which makes that the accelerator is kept operational with respect to misalignments. The annual leveling of LEP can be characterised as follows: - A quasi circle of 27 km circumference in tunnel; - Measurements with a LEICA NA3000 (σ = ± 0.4 mm/km, statistically ± 0.04 to ± 0.05 mm/station, at intervals of 39.5 m); - Maximum height difference of 120 m between the highest point and the lowest point; - Measured points: alignment reference targets of the quadrupole magnets (entrance and exit points); -800 quadrupole magnets, 1600 points to measure; - Cholesky method, with two independent traverses (forward/backward loops). The data processing is made by least squares, according to a free network concept. In addition, a smoothing procedure (successive fits within a sliding window) is also carried out after each annual leveling measurement, in the purpose of refining the successive positions and finding the points being vertically too far (more than 0.3 mm in general) from the local smoothing curve. These points are then brought physically on their smoothed position (realignment) in order to keep the vertical configuration of LEP as optimal as possible. Tilt (transverse slope) measurements are also taken during this realignment process, thus putting the corrected element back to its right transverse position and reducing the correlated radial movement associated to this defect. (authors)

  1. Magnetic-field-induced squeezing effect at energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider

    Science.gov (United States)

    Pang, Long-Gang; Endrődi, Gergely; Petersen, Hannah

    2016-04-01

    In off-central heavy-ion collisions, quark-gluon plasma (QGP) is exposed to the strongest magnetic fields ever created in the universe. Because of the paramagnetic nature of the QGP at high temperatures, the spatially inhomogeneous magnetic field configuration exerts an anisotropic force density that competes with the pressure gradients resulting from purely geometric effects. In this paper, we simulate (3+1)-dimensional ideal hydrodynamics with external magnetic fields to estimate the effect of this force density on the anisotropic expansion of the QGP in collisions at the Relativistic Heavy Ion Collider and at the Large Hadron Collider (LHC). While negligible for quickly decaying magnetic fields, we find that long-lived fields generate a substantial force density that suppresses the momentum anisotropy of the plasma by up to 20 % at the LHC energy and also leaves its imprint on the elliptic flow v2 of charged pions.

  2. Chiral electric field in relativistic heavy-ion collisions at energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider

    Science.gov (United States)

    Zhong, Yang; Yang, Chun-Bin; Cai, Xu; Feng, Sheng-Qin

    2016-08-01

    It has been proposed that electric fields may lead to chiral separation in quark-gluon plasma (QGP). This is called the chiral electric separation effect. The strong electromagnetic field and the QCD vacuum can both be completely produced in off-central nuclear-nuclear collision. We use the Woods-Saxon nucleon distribution to calculate the electric field distributions of off-central collisions. The chiral electric field spatial distribution at Relativistic Heavy-Ion Collider (RHIC) and Large Hadron Collider (LHC) energy regions are systematically studied in this paper. The dependence of the electric field produced by the thermal quark in the central position with different impact parameters on the proper time with different collision energies in the RHIC and LHC energy regions are studied in this paper. Supported by National Natural Science Foundation of China (11375069, 11435054, 11075061, 11221504) and Key Laboratory Foundation of Quark and Lepton Physics (Hua-Zhong Normal University)(QLPL2014P01)

  3. CERN: ALICE in the looking-glass

    International Nuclear Information System (INIS)

    While proton-proton collisions will provide the main research thrust at CERN's planned LHC high energy collider to be built in the LEP tunnel, its 27-kilometre superconducting magnet ring will also be able to handle all the other high energy beams on the CERN menu, opening up the possibility of both heavy ion and electron-proton collisions to augment the LHC research programme. A major new character in the LHC cast - ALICE (A Large Ion Collider Experiment) - has recently published a letter of intent, announcing its intention to appear on the LHC stage. Three letters of intent for major LHC proton-proton experiments were aired last year (January, page 6), and ALICE, if approved, would cohabit with the final solution for the protonproton sector (see box). Only a single major heavy ion experiment is envisaged. The protonproton detectors have some heavy ion capability, but could only look at some very specific signals. (Detailed plans for LHC's electron proton collision option are on hold, awaiting the initial exploration of this field by the new HERA collider which came into operation last year at the DESY Laboratory in Hamburg.) Describing the ALICE detector and its research aims, spokesman Jurgen Schukraft echoes T.D.Lee's observations on the state of particle physics. It is becoming increasingly clear that resolving some of today's particle puzzles require a deeper understanding of the vacuum

  4. LEP vacuum chamber cross-section

    CERN Multimedia

    1987-01-01

    This diagram shows the layout of the vacuum chambers used at LEP, which was in operation at CERN between 1989 and 2000. Vacuum chambers are necessary in accelerators to prevent unwanted interactions that can destabilise the beam. The pump on the right sucks air out of the chamber allowing the beam to progress with minimal interactions.

  5. A Study of J/psi Production at the LEP $e^{+} e{-}$ Collider; and the Implementation of the DELPHI Slow Controls System

    CERN Document Server

    Adye, T J

    1998-01-01

    This thesis describes two separate areas of work conducted for the DELPHI detector at LEP. The first concerns the Slow Controls of the DELPHI detector, which enable a single operator to oversee the proper functioning of the apparatus and to diagnose faults as they occur. The hardware and software of this system, as well as their interface to the experiment and the operator, are described. Some conclusions are drawn from seven years' design work and the initial six years' operation of DELPHI. Secondly, a study is made of the production, at e+e- collision centre of mass energies close to the Z0 resonance, of J/psi mesons, decaying to mu+ mu-. J/psi mesons produced via a B-hadron are used to measure the mean B lifetime, tau_B = (1.53 +- 0.11 (stat.) +- 0.06 (syst.)) ps A measurement is also made of the fraction of J/psis produced promptly at the e+e- collision point, N(Z0 -> prompt J/psi X) / N(Z0 -> J/psi X) = (9.6 +- 3.2 (stat.) +- 1.2 (syst.))%. This method is largely model-independent.

  6. Entropy production in chemically nonequilibrium quark-gluon plasma created in central Pb +Pb collisions at energies available at the CERN Large Hadron Collider

    Science.gov (United States)

    Vovchenko, V.; Gorenstein, M. I.; Satarov, L. M.; Mishustin, I. N.; Csernai, L. P.; Kisel, I.; Stöcker, H.

    2016-01-01

    We study the possibility that partonic matter produced at an early stage of ultrarelativistic heavy-ion collisions is out of chemical equilibrium. It is assumed that initially this matter is mostly composed of gluons, but quarks and antiquarks are produced at later times. The dynamical evolution of partonic system is described by the Bjorken-like ideal hydrodynamics with a time-dependent quark fugacity. The results of this model are compared with those obtained by assuming the complete chemical equilibrium of partons already at the initial stage. It is shown that in a chemically nonequilibrium scenario the entropy gradually increases, and about 25% of the total final entropy is generated during the hydrodynamic evolution of deconfined matter. We argue that the (anti)quark suppression included in this approach may be responsible for reduced (anti)baryon-to-meson ratios observed in heavy-ion collisions at energies available at the CERN Large Hadron Collider.

  7. The vacuum chamber in the interaction region of particle colliders : a historical study and developments implemented in the LHCb experiment at CERN

    OpenAIRE

    Knaster Refolio, Juan Ramón

    2004-01-01

    El colisionador de protenes actualmente en construcción en el CERN llamado LHC (Large Hadron Collider) se convertirá en el más potente acelerador jamas construido con una energía por protón de 7 TeV. Se prevé que esta en operación en 2007. Constará de 4 grandes experimentos uno de los cuales, LHCb, se dedicará a la investigación de la violación CP. Los requerimientos de la cámara de vacío de los experimentos en colisionadores de partículas son muy especiales. La presente tesis doctoral, en un...

  8. Linear colliders

    International Nuclear Information System (INIS)

    From November 28 to December 9, the Stanford Linear Accelerator Center hosted an International Workshop on Next Generation Linear Colliders. The attendance, including delegations from CERN, Frascati (Italy), KEK (Japan), Livermore (US), Novosibirsk (USSR), Drsay (France) and SLAC itself reflected the international interest in this new approach to higher energies

  9. First measurement and correction of nonlinear errors in the experimental insertions of the CERN Large Hadron Collider

    Science.gov (United States)

    Maclean, E. H.; Tomás, R.; Giovannozzi, M.; Persson, T. H. B.

    2015-12-01

    Nonlinear magnetic errors in low-β insertions can contribute significantly to detuning with amplitude, linear and nonlinear chromaticity, and lead to degradation of dynamic aperture and beam lifetime. As such, the correction of nonlinear errors in the experimental insertions of colliders can be of critical significance for successful operation. This is expected to be of particular relevance to the LHC's second run and its high luminosity upgrade, as well as to future colliders such as the Future Circular Collider. Current correction strategies envisioned for these colliders assume it will be possible to calculate optimized local corrections through the insertions, using a magnetic model of the errors. This paper shows however, that reliance purely upon magnetic measurements of the nonlinear errors of insertion elements is insufficient to guarantee a good correction quality in the relevant low-β* regime. It is possible to perform beam-based examination of nonlinear magnetic errors via the feed-down to readily observed beam properties upon application of closed orbit bumps, and methods based upon feed-down to tune have been utilized at RHIC, SIS18, and SPS. This paper demonstrates the extension of such methodology to include direct observation of feed-down to linear coupling in the LHC. It is further shown that such beam-based studies can be used to complement magnetic measurements performed during LHC construction, in order to validate and refine the magnetic model of the collider. Results from first attempts of the measurement and correction of nonlinear errors in the LHC experimental insertions are presented. Several discrepancies of beam-based studies with respect to the LHC magnetic model are reported.

  10. LEP - Large Electron Positron Exhibition LEPFest 2000

    CERN Multimedia

    2000-01-01

    The Large Electron-Positron Collider (LEP) is 27 km long. Its four detectors (ALEPH, DELPHI, L3, OPAL) measure precisely what happens in the collisions of electrons and positrons. These conditions only exist-ed in the Universe when it was about 10 -10 sec old.

  11. Beam Effects on the Cryogenic System of LEP2

    CERN Document Server

    Gayet, P; Winkler, G

    1998-01-01

    The LEP collider was operated during 1996 for the first time with superconducting cavities at the four interaction points. During operation for physics it was observed that the dissipated heat in the cavities is not only a function of the acceleration gradient, but depends also on beam characteristics such as intensity, bunch length and beam current. These beam effects had not been foreseen in the original heat budget of the LEP cryogenic system. The observations indicating the beam effect and its origin are presented. The available capacity of the refrigerators demonstrates that cryogenics might become a limiting factor for the performance of the LEP collider.

  12. The Large Hadron Collider and the Super Proton Synchrotron at CERN as Tools to Generate Warm Dense Matter and Non–Ideal Plasmas

    CERN Document Server

    Tahir, N A; Shutov, A; Lomonosov, I V; Gryaznov, V; Piriz, A R; Deutsch, C; Fortov, V E

    2011-01-01

    The largest accelerator in the world, the Large Hadron Collider (LHC) at CERN, has entered into commission- ing phase. It is expected that when this impressive machine will become fully operational, it will generate two counter rotating 7 TeV/c proton beams that will be made to collide, leading to an unprecedented luminosity of 1034 cm−2s−1. Total energy stored in each LHC beam is about 362 MJ, sufficient to melt 500 kg copper. Safety of operation is a very critical issue when working with such extremely powerful beams. It is important to know the consequences of an accidental release of the beam energy in order to design protection system for the equipment. For this purpose we have carried out extensive numerical simulations of the interaction of one full LHC beam with copper and graphite targets which are materials of practical importance. Our calculations have shown that the LHC protons will penetrate up to about 35 m in solid copper and 10 m in solid graphite. A very interesting outcome of this work i...

  13. The Large Hadron Collider and the Super Proton Synchrotron at CERN as Tools to Generate Warm Dense Matter and Non-Ideal Plasmas

    CERN Document Server

    Tahir, N A; Deutsch, C; Gryaznov, V; Lomonosov, I V; Shutov, A; Piriz, A R; Fortov, V E; Geissel, H; Redmer, R

    2011-01-01

    The largest accelerator in the world, the Large Hadron Collider (LHC) at CERN, has entered into commissioning phase. It is expected that when this impressive machine will become fully operational, it will generate two counter rotating 7 TeV/c proton beams that will be made to collide, leading to an unprecedented luminosity of 10(34) cm(-2)s(-1). Total energy stored in each LHC beam is about 362 MJ, sufficient to melt 500 kg copper. Safety of operation is a very critical issue when working with such extremely powerful beams. It is important to know the consequences of an accidental release of the beam energy in order to design protection system for the equipment. For this purpose we have carried out extensive numerical simulations of the interaction of one full LHC beam with copper and graphite targets which are materials of practical importance. Our calculations have shown that the LHC protons will penetrate up to about 35 m in solid copper and 10 m in solid graphite. A very interesting outcome of this work i...

  14. Electroweak Measurements in Electron-Positron Collisions at W-Boson-Pair Energies at LEP

    CERN Document Server

    Schael, S; Bruneliere, R; Buskulic, D; De Bonis, I; Decamp, D; Ghez, P; Goy, C; Jezequel, S; Lees, J P; Lucotte, A; Martin, F; Merle, E; Minard, M N; Nief, J Y; Odier, P; Pietrzyk, B; Trocme, B; Bravo, S; Casado, M P; Chmeissani, M; Comas, P; Crespo, J M; Fernandez, E; Fernandez-Bosman, M; Garrido, Ll; Grauges, E; Juste, A; Martinez, M; Merino, G; Miquel, R; Mir, Ll. M; Orteu, S; Pacheco, A; Park, I C; Perlas, J; Riu, I; Ruiz, H; Sanchez, F; Colaleo, A; Creanza, D; De Filippis, N; De Palma, M; Iaselli, G; Maggi, G; Maggi, M; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Bazarko, A; Becker, U; Boix, G; Bird, F; Blucher, E; Bonvicini, B; Bright-Thomas, P; Barklow, T; Buchmuller, O; Cattaneo, M; Cerutti, F; Ciulli, V; Clerbaux, B; Drevermann, H; Forty, R W; Frank, M; Greening, T C; Hagelberg, R; Halley, A W; Gianotti, F; Girone, M; Hansen, J B; Harvey, J; Jacobsen, R; Hutchcroft, D E; Janot, P; Jost, B; Knobloch, J; Kado, M; Lehraus, I; Lazeyras, P; Maley, P; Mato, P; May, J; Moutoussi, A; Pepe-Altarelli, M; Ranjard, F; Rolandi, L; Schlatter, D; Schmitt, B; Schneider, O; Tejessy, W; Teubert, F; Tomalin, I R; Tournefier, E; Veenhof, R; Valassi, A; Wiedenmann, W; Wright, A E; Ajaltouni, Z; Badaud, F; Chazelle, G; Deschamps, O; Dessagne, S; Falvard, A; Ferdi, C; Fayolle, D; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Pascolo, J M; Perret, P; Podlyski, F; Bertelsen, H; Fernley, T; Hansen, J D; Hansen, J R; Hansen, P H; Kraan, A C; Lindahl, A; Mollerud, R; Nilsson, B S; Rensch, B; Waananen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, E; Siotis, I; Vayaki, A; Zachariadou, K; Blondel, A; Bonneaud, G; Brient, J C; Machefert, F; Rouge, A; Rumpf, M; Swynghedauw, M; Tanaka, R; Verderi, M; Videau, H; Ciulli, V; Focardi, E; Parrini, G; Zachariadou, K; Corden, M; Georgiopoulos, C; Antonelli, A; Antonelli, M; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Cerutti, F; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, G P; Passalacqua, L; Picchi, P; Colrain, P; Have, I. ten; Hughes, I S; Kennedy, J; Knowles, I G; Lynch, J G; Morton, W T; Negus, P; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Thompson, A S; Turnbull, R M; Wasserbaech, S; Buchmuller, O; Cavanaugh, R; Dhamotharan, S; Geweniger, C; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Sommer, J; Stenzel, H; Tittel, K; Werner, W; Wunsch, M; Beuselinck, R; Binnie, D M; Cameron, W; Davies, G; Dornan, P J; Goodsir, S; Marinelli, N; Martin, E B; Nash, J; Nowell, J; Rutherford, S A; Sedgbeer, J K; Thompson, J C; White, R; Williams, M D; Ghete, V M; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Bouhova-Thacker, E; Bowdery, C K; Buck, P G; Clarke, D P; Ellis, G; Finch, A J; Foster, F; Hughes, G; Jones, R.W L; Keemer, N R; Pearson, M R; Robertson, N A; Sloan, T; Smizanska, M; Snow, S W; Williams, M I; van der Aa, O; Delaere, C; Leibenguth, G; Lemaitre, V; Bauerdick, L.A T; Blumenschein, U; van Gemmeren, P; Giehl, I; Holldorfer, F; Jakobs, K; Kasemann, M; Kayser, F; Kleinknecht, K; Muller, A S; Quast, G; Renk, B; Rohne, E; Sander, H G; Schmeling, S; Wachsmuth, H; Wanke, R; Zeitnitz, C; Ziegler, T; Aubert, J J; Benchouk, C; Bonissent, A; 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Ferrari, P; Fiedler, F; Fierro, M; Fischer, H M; Fleck, I; Folman, R; Fong, D G; Ford, M; Foucher, M; Frey, A; Furtjes, A; Futyan, D I; Gagnon, P; Gary, J W; Gascon, J; Gascon-Shotkin, S M; Gaycken, G; Geddes, N I; Geich-Gimbel, C; Geralis, T; Giacomelli, G; Giacomelli, P; Giacomelli, R; Gibson, V; Gibson, W R; Gingrich, D M; Giunta, M; Glenzinski, D; Goldberg, J; Goodrick, M J; Gorn, W; Graham, K; Grandi, C; Gross, E; Grunhaus, J; Gruwe, M; Gunther, P O; Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Hansroul, M; Hapke, M; Harder, K; Harel, A; Hargrove, C K; Harin-Dirac, M; Hart, P A; Hartmann, C; Hauke, A; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, R J; Hensel, C; Herndon, M; Herten, G; Heuer, R D; Hildreth, M D; Hill, J C; Hillier, S J; Hilse, T; Hobson, P R; Hocker, A; Hoffman, K; Homer, R J; Honma, A K; Horvath, D; Hossain, K R; Howard, R; Hughes-Jones, R E; Huntemeyer, P; Hutchcroft, D E; Igo-Kemenes, P; Imrie, D C; Ingram, M R; Ishii, K; Jacob, F R; Jawahery, A; Jeffreys, P W; Jeremie, H; Jimack, M; Joly, A; Jones, C R; Jones, G; Jones, M; Jones, R.W L; Jost, U; Jovanovic, P; Junk, T R; Kanaya, N; Kanzaki, J; Karapetian, G; Karlen, D; Kartvelishvili, V; Kawagoe, K; Kawamoto, T; Keeler, R K; Kellogg, R G; Kennedy, B W; Kim, D H; King, B J; Kirk, J; Klein, K; Klier, A; Kluth, S; Kobayashi, T; Kobel, M; Koetke, D S; Kokott, T P; Kolrep, M; Komamiya, S; Kowalewski, R V; Kramer, T; Krasznahorkay, A., Jr; Kress, T; Krieger, P; von Krogh, J; Kuhl, T; Kupper, M; Kyberd, P; Lafferty, G D; Lahmann, R; Lai, W P; Landsman, H; Lanske, D; Lauber, J; Lautenschlager, S R; Lawson, I; Layter, J G; Lazic, D; Lee, A M; Lefebvre, E; Leins, A; Lellouch, D; Letts, J; Levinson, L; Lewis, C; Liebisch, R; Lillich, J; List, B; List, J; Littlewood, C; Lloyd, A W; Lloyd, S L; Loebinger, F K; Long, G D; Losty, M J; Lu, J; Ludwig, A; Ludwig, J; Macchiolo, A; Macpherson, A; Mader, W; Mannelli, M; Marcellini, S; Marchant, T E; Markus, C; Martin, A J; Martin, J P; Martinez, G; Mashimo, T; Matthews, W; Mattig, P; McDonald, W J; McKenna, J; Mckigney, E A; McMahon, T J; McNab, A I; McPherson, R A; Mendez-Lorenzo, P; Meijers, F; Menges, W; Menke, S; Merritt, F S; Mes, H; Meyer, N; Meyer, J; Michelini, A; Mihara, S; Mikenberg, G; Miller, D J; Mir, R; Mohr, W; Montanari, A; Mori, T; Morii, M; Muller, U; Mutter, A; Nagai, K; Nakamura, I; Nanjo, H; Neal, H A; Nellen, B; Nijjhar, B; Nisius, R; O'Neale, S W; Oakham, F G; Odorici, F; Ogren, H O; Oh, A; Okpara, A; Oldershaw, N J; Omori, T; Oreglia, M J; Orito, S; Pahl, C; Palinkas, J; Pasztor, G; Pater, J R; Patrick, G N; Patt, J; Pearce, M J; Petzold, S; Pfeifenschneider, P; Pilcher, J E; Pinfold, J; Plane, D E; Poffenberger, P; Polok, J; Poli, B; Pooth, O; Posthaus, A; Przybycien, M; Przysiezniak, H; Quadt, A; Rabbertz, K; Rees, D L; Rembser, C; Renkel, P; Rick, H; Rigby, D; Robertson, S; Robins, S A; Rodning, N; Roney, J M; Rooke, A; Ros, E; Rosati, S; Roscoe, K; Rossi, A M; Rosvick, M; Routenburg, P; Rozen, Y; Runge, K; Runolfsson, O; Ruppel, U; Rust, D R; Rylko, R; Sachs, K; Saeki, T; Sahr, O; Sarkisyan, E.K G; Sasaki, M; Sbarra, C; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schenk, P; Schieck, J; Schmitt, S; Schorner-Sadenius, T; Schroder, M; Schultz-Coulon, H C; Schulz, M; Schumacher, M; Schutz, P; Schwick, C; Scott, W G; Seuster, R; Shears, T G; Shen, B C; Shepherd-Themistocleous, C H; Sherwood, P; Siroli, G P; Sittler, A; Skillman, A; Skuja, A; Smith, A M; Smith, T J; Snow, G A; Sobie, R; Soldner-Rembold, S; Spagnolo, S; Spano, F; Springer, R W; Sproston, M; Stahl, A; Steiert, M; Stephens, K; Steuerer, J; Stockhausen, B; Stoll, K; Strom, D; Strohmer, R; Strumia, F; Stumpf, L; Surrow, B; Szymanski, P; Tafirout, R; Talbot, S D; Tanaka, S; Taras, P; Tarem, S; Taylor, R J; Tasevsky, M; Teuscher, R; Thiergen, M; Thomas, J; Thomson, M A; von Torne, E; Torrence, E; Towers, S; Toya, D; Trefzger, T; Trigger, I; Trocsanyi, Z; Tsukamoto, T; Tsur, E; Turcot, A S; Turner-Watson, M F; Ueda, I; Ujvari, B; Utzat, P; Vachon, B; Van Kooten, R; Vannerem, P; Vertesi, R; Verzocchi, M; Vikas, P; Vincter, M; Vokurka, E H; Vollmer, C F; Voss, H; Vossebeld, J; Wackerle, F; Wagner, A; Waller, D; Ward, C P; Ward, D R; Ward, J J; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wetterling, D; White, J S; Wilkens, B; Wilson, G W; Wilson, J A; Wolf, G; Wotton, S; Wyatt, T R; Yamashita, S; Yekutieli, G; Zacek, V; Zer-Zion, D; Zivkovic, L

    2013-01-01

    Electroweak measurements performed with data taken at the electron-positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3~fb$^{-1}$ collected by the four LEP experiments ALEPH, DELPHI, L3 and OPAL, at centre-of-mass energies ranging from $130~GeV$ to $209~GeV$. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron-positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose-Einstein correlations between the two W decay systems arising ...

  15. Fault detection on the Large Hadron Collider at CERN: design, simulation and realization of a High Voltage Pulse Generator

    CERN Document Server

    Cavicchioli, C; Biagi, E; Bozzini, D

    2007-01-01

    This project was developed inside the Quality Assurance Plan (ELQA) of the LHC. The superconducting circuits of the collider show a great complexity concerning the control system, because of various reasons: the tunnel is placed around 50 to 175 m underground, the circuits work at temperatures of 1.9 K, all the structure should be perfectly aligned and the electronic part has considerable dimensions. To maximize the running time of the collider, it is necessary to develop methods for the diagnostic of defects and for the precise localization of the segment of the accelerator that contains the fault. From my studies it emerged that a possible way to localize electrical faults in the LHC superconducting circuits is to combine the use of time domain reflectometry methods and high voltage pulses. Therefore, I have designed and realized a high voltage pulse generator that will be an important instrument for the fault location among the accelerator.

  16. A Large Hadron Electron Collider at CERN: Report on the Physics and Design Concepts for Machine and Detector

    CERN Document Server

    Abelleira Fernandez, J L; Akay, A N; Aksakal, H; Albacete, J L; Alekhin, S; Allport, P; Andreev, V; Appleby, R B; Arikan, E; Armesto, N; Azuelos, G; Bai, M; Barber, D; Bartels, J; Behnke, O; Behr, J; Belyaev, A S; Ben-Zvi, I; Bernard, N; Bertolucci, S; Bettoni, S; Biswal, S; Blumlein, J; Bottcher, H; Bogacz, A; Bracco, C; Brandt, G; Braun, H; Brodsky, S; Brüning, O; Bulyak, E; Buniatyan, A; Burkhardt, H; Cakir, I T; Cakir, O; Calaga, R; Cetinkaya, V; Ciapala, E; Ciftci, R; Ciftci, A K; Cole, B A; Collins, J C; Dadoun, O; Dainton, J; De Roeck, A; d'Enterria, D; Dudarev, A; Eide, A; Enberg, R; Eroglu, E; Eskola, K J; Favart, L; Fitterer, M; Forte, S; Gaddi, A; Gambino, P; Garcia Morales, H; Gehrmann, T; Gladkikh, P; Glasman, C; Godbole, R; Goddard, B; Greenshaw, T; Guffanti, A; Guzey, V; Gwenlan, C; Han, T; Hao, Y; Haug, F; Herr, W; Herve, A; Holzer, B J; Ishitsuka, M; Jacquet, M; Jeanneret, B; Jimenez, J M; Jowett, J M; Jung, H; Karadeniz, H; Kayran, D; Kilic, A; Kimura, K; Klein, M; Klein, U; Kluge, T; Kocak, F; Korostelev, M; Kosmicki, A; Kostka, P; Kowalski, H; Kramer, G; Kuchler, D; Kuze, M; Lappi, T; Laycock, P; Levichev, E; Levonian, S; Litvinenko, V N; Lombardi, A; Maeda, J; Marquet, C; Mellado, B; Mess, K H; Milanese, A; Moch, S; Morozov, I I; Muttoni, Y; Myers, S; Nandi, S; Nergiz, Z; Newman, P R; Omori, T; Osborne, J; Paoloni, E; Papaphilippou, Y; Pascaud, C; Paukkunen, H; Perez, E; Pieloni, T; Pilicer, E; Pire, B; Placakyte, R; Polini, A; Ptitsyn, V; Pupkov, Y; Radescu, V; Raychaudhuri, S; Rinol, L; Rohini, R; Rojo, J; Russenschuck, S; Sahin, M; Salgado, C A; Sampei, K; Sassot, R; Sauvan, E; Schneekloth, U; Schorner-Sadenius, T; Schulte, D; Senol, A; Seryi, A; Sievers, P; Skrinsky, A N; Smith, W; Spiesberger, H; Stasto, A M; Strikman, M; Sullivan, M; Sultansoy, S; Sun, Y P; Surrow, B; Szymanowski, L; Taels, P; Tapan, I; Tasci, T; Tassi, E; Ten Kate, H; Terron, J; Thiesen, H; Thompson, L; Tokushuku, K; Tomas Garcia, R; Tommasini, D; Trbojevic, D; Tsoupas, N; Tuckmantel, J; Turkoz, S; Trinh, T N; Tywoniuk, K; Unel, G; Urakawa, J; VanMechelen, P; Variola, A; Veness, R; Vivoli, A; Vobly, P; Wagner, J; Wallny, R; Wallon, S; Watt, G; Weiss, C; Wiedemann, U A; Wienands, U; Willeke, F; Xiao, B W; Yakimenko, V; Zarnecki, A F; Zhang, Z; Zimmermann, F; Zlebcik, R; Zomer, F

    2012-01-01

    The physics programme and the design are described of a new collider for particle and nuclear physics, the Large Hadron Electron Collider (LHeC), in which a newly built electron beam of 60 GeV, up to possibly 140 GeV, energy collides with the intense hadron beams of the LHC. Compared to HERA, the kinematic range covered is extended by a factor of twenty in the negative four-momentum squared, $Q^2$, and in the inverse Bjorken $x$, while with the design luminosity of $10^{33}$ cm$^{-2}$s$^{-1}$ the LHeC is projected to exceed the integrated HERA luminosity by two orders of magnitude. The physics programme is devoted to an exploration of the energy frontier, complementing the LHC and its discovery potential for physics beyond the Standard Model with high precision deep inelastic scattering measurements. These are designed to investigate a variety of fundamental questions in strong and electroweak interactions. The physics programme also includes electron-deuteron and electron-ion scattering in a $(Q^2, 1/x)$ ran...

  17. Looking For Physics Beyond The Standard Model: Searches For Charged Higgs Bosons At $e^{+}e^{-}$ Colliders

    CERN Document Server

    Kiiskinen, A P

    2004-01-01

    This thesis describes direct searches for pair production of charged Higgs bosons performed in the data collected by the DELPHI detector at the LEP collider at CERN. In addition, the possibilities to discover and study heavy charged Higgs bosons at possible future high-energy linear colliders are presented. The existence of charged Higgs bosons is predicted by many extensions of the Standard Model. A possible discovery of these particles would be a solid proof for physics beyond the Standard Model. Discovery of charged Higgs bosons, and measurement of their properties, would also provide useful information about the structure of the more general theory. New analysis methods were developed for the searches performed at LEP. A large, previously unexplored, mass range for cover but no evidence for the existence of the charged Higgs bosons was found. This allowed setting new lower mass limits for the charged Higgs boson within the framework of general two Higgs doublet models. Results have been interpreted and pr...

  18. Signatures of the anomalous Zγ and ZZ production at lepton and hadron colliders

    Science.gov (United States)

    Gounaris, G. J.; Layssac, J.; Renard, F. M.

    2000-04-01

    The possible form of new physics (NP) interactions affecting the ZZZ, ZZγ, and Zγγ vertices is critically examined. Their signatures and the possibilities to study them, through ZZ and Zγ production, at the CERN e-e+ colliders LEP and LC and at the hadronic colliders, the Fermilab Tevatron and CERN LHC, are investigated. Experimental limits obtained or expected on each coupling are collected. A simple theoretical model based on virtual effects due to some heavy fermions is used for acquiring some guidance on the plausible forms of these NP vertices. In such a case specific relations among the various neutral couplings are predicted, which can be experimentally tested and possibly used to constrain the form of the responsible NP structure.

  19. Signatures of the anomalous Z gamma and ZZ production at lepton and hadron colliders

    CERN Document Server

    Gounaris, George J; Renard, F M

    2000-01-01

    The possible form of new physics (NP) interactions affecting the ZZZ, ZZ gamma , and Z gamma gamma vertices is critically examined. Their signatures and the possibilities to study them, through ZZ and Z gamma production, at the CERN e/sup -/e/sup +/ colliders LEP and LC and at the hadronic colliders, the Fermilab Tevatron and CERN LHC, are investigated. Experimental limits obtained or expected on each coupling are collected. A simple theoretical model based on virtual effects due to some heavy fermions is used for acquiring some guidance on the plausible forms of these NP vertices. In such a case specific relations among the various neutral couplings are predicted, which can be experimentally tested and possibly used to constrain the form of the responsible NP structure. (21 refs).

  20. Exclusive beauty physics at the Z0 pole. Analysis techniques and research results and recent results from the DELPHI experiment at LEP

    International Nuclear Information System (INIS)

    The analysis of about 1.7 Million Z0 hadronic decays, recorded with the DELPHI detector at the CERN LEP collider, has already provided a number of results in exclusive heavy flavour physics. Recent studies on the determination of the exclusive B lifetimes, the measurement of the Bs and Λb masses and the search for rare b decays are reviewed. Special emphasis is given to the analysis techniques developed in order to exploit the accurate tracking and hadron identification capabilities of the DELPHI apparatus. These analysis techniques represent a starting point for the study of beauty physics at the next generation of experimental facilities, as high luminosity B factories. (author)

  1. Another Detector for the International Linear Collider

    CERN Document Server

    Akchurin, Nural; Wigmans, Richard; Arnold, Hanna; Bazal, Aaron; Basili, Robert; Hauptman, John; Overton, Tim; Priest, Andrew; Zhao, Bingzhe; Mikhailichenko, Alexander; Cascella, Michele; Grancagnolo, Franco; Tassielli, Giovanni; Bedeschi, Franco; Scuri, Fabrizio; Park, Sung Keun; Ignatov, Fedor; Gaudio, Gabriella; Livan, Michele

    2013-01-01

    We describe another detectora designed for the International Linear Collider based on several tested instrumentation innovations in order to achieve the necessary experi- mental goal of a detecter that is 2-to-10 times better than the already excellent SLC and LEP detectors, in particular, (1) dual-readout calorimeter system based on the RD52/DREAM measurements at CERN, (2) a cluster-counting drift chamber based on the successful kloe chamber at Frascati, and (3) a second solenoid to return the magnetic flux without iron. A high-performance pixel vertex chamber is presently un- defined. We discuss particle identification, momentum and energy resolutions, and the machine-detector interface that together offer the possibility of a very high-performance detector for $e^+e^-$physics up to $\\sqrt{s} = 1$ TeV.

  2. Ion colliders

    International Nuclear Information System (INIS)

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions (77Asb1, 81Bou1). The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

  3. Coherent photoproduction of vector mesons in ultraperipheral heavy ion collisions: Update for run 2 at the CERN Large Hadron Collider

    Science.gov (United States)

    Guzey, V.; Kryshen, E.; Zhalov, M.

    2016-05-01

    We make predictions for the cross sections of coherent photoproduction of ρ ,ϕ ,J /ψ ,ψ (2 S ) , and Υ (1 S ) mesons in Pb-Pb ultraperipheral collisions (UPCs) at √{sN N}=5.02 TeV in the kinematics of run 2 at the Large Hadron Collider extending the approaches successfully describing the available Pb-Pb UPC data at √{sN N}=2.76 TeV . Our results illustrate the important roles of hadronic fluctuations of the photon and inelastic nuclear shadowing in photoproduction of light vector mesons on nuclei and the large leading twist nuclear gluon shadowing in photoproduction of quarkonia on nuclei. We show that the ratio of ψ (2 S ) and J /ψ photoproduction cross sections in Pb-Pb UPCs is largely determined by the ratio of these cross sections on the proton. We also argue that UPCs with electromagnetic excitations of the colliding ions followed by the forward neutron emission allows one to significantly increase the range of photon energies accessed in vector meson photoproduction on nuclei.

  4. Proton enhancement at large pT at the CERN large hadron collider without structure in associated-particle distribution.

    Science.gov (United States)

    Hwa, Rudolph C; Yang, C B

    2006-07-28

    The production of pions and protons in the pT range between 10 and 20 GeV/c for Pb+Pb collisions at CERN LHC is studied in the recombination model. It is shown that the dominant mechanism for hadronization is the recombination of shower partons from neighboring jets when the jet density is high. Protons are more copiously produced than pions in that pT range because the coalescing partons can have lower momentum fractions, but no thermal partons are involved. The proton-to-pion ratio can be as high as 20. When such high pT hadrons are used as trigger particles, there will not be any associated particles that are not in the background.

  5. Ion Colliders

    CERN Document Server

    Fischer, W

    2014-01-01

    High-energy ion colliders are large research tools in nuclear physics to study the Quark-Gluon-Plasma (QGP). The range of collision energy and high luminosity are important design and operational considerations. The experiments also expect flexibility with frequent changes in the collision energy, detector fields, and ion species. Ion species range from protons, including polarized protons in RHIC, to heavy nuclei like gold, lead and uranium. Asymmetric collision combinations (e.g. protons against heavy ions) are also essential. For the creation, acceleration, and storage of bright intense ion beams, limits are set by space charge, charge change, and intrabeam scattering effects, as well as beam losses due to a variety of other phenomena. Currently, there are two operating ion colliders, the Relativistic Heavy Ion Collider (RHIC) at BNL, and the Large Hadron Collider (LHC) at CERN.

  6. Particle multiplicities in lead-lead collisions at the CERN large hadron collider from nonlinear evolution with running coupling corrections.

    Science.gov (United States)

    Albacete, Javier L

    2007-12-31

    We present predictions for the pseudorapidity density of charged particles produced in central Pb-Pb collisions at the LHC. Particle production in such collisions is calculated in the framework of k(t) factorization. The nuclear unintegrated gluon distributions at LHC energies are determined from numerical solutions of the Balitsky-Kovchegov equation including recently calculated running coupling corrections. The initial conditions for the evolution are fixed by fitting Relativistic Heavy Ion Collider data at collision energies square root[sNN]=130 and 200 GeV per nucleon. We obtain dNch(Pb-Pb)/deta(square root[sNN]=5.5 TeV)/eta=0 approximately 1290-1480.

  7. Department of Energy assessment of the Large Hadron Collider

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This report summarizes the conclusions of the committee that assessed the cost estimate for the Large Hadron Collider (LHC). This proton-proton collider will be built at CERN, the European Laboratory for Particle Physics near Geneva, Switzerland. The committee found the accelerator-project cost estimate of 2.3 billion in 1995 Swiss francs, or about $2 billion US, to be adequate and reasonable. The planned project completion date of 2005 also appears achievable, assuming the resources are available when needed. The cost estimate was made using established European accounting procedures. In particular, the cost estimate does not include R and D, prototyping and testing, spare parts, and most of the engineering labor. Also excluded are costs for decommissioning the Large Electron-Positron collider (LEP) that now occupies the tunnel, modifications to the injector system, the experimental areas, preoperations costs, and CERN manpower. All these items are assumed by CERN to be included in the normal annual operations budget rather than the construction budget. Finally, contingency is built into the base estimate, in contrast to Department of Energy (DOE) estimates that explicitly identify contingency. The committee`s charge, given by Dr. James F. Decker, Deputy Directory of the DOE Office of Energy Research, was to understand the basis for the LHC cost estimate, identify uncertainties, and judge the overall validity of the estimate, proposed schedule, and related issues. The committee met at CERN April 22--26, 1996. The assessment was based on the October 1995 LHC Conceptual Design Report or ``Yellow Book,`` cost estimates and formal presentations made by the CERN staff, site inspection, detailed discussions with LHC technical experts, and the committee members` considerable experience.

  8. High energy accelerator and colliding beam user group. Progress report, March 1, 1983-February 29, 1984

    International Nuclear Information System (INIS)

    Topics covered in this research summary include: status of the OPAL collaboration at LEP, CERN; two-photon physics at PLUTO; search for new particles at JADE; neutrinoless double beta decay at DESY; Fermilab jet experiment; neutrino deuterium experiment in the 15 foot bubble chamber at Fermilab; deep inelastic muon experiment at Fermilab; new experiments at the proton-antiproton collider; neutrino-electron scattering at Los Alamos; parity violation in proton-proton scattering; an upgrade of laboratory and computer facilities; and a study of bismuth germanate as a durable scintillation crystal

  9. Reliability of the beam loss monitors system for the large hadron collider at CERN; Fiabilite du systeme des moniteurs de pertes du faisceau pour le Large Hadron Collider au CERN

    Energy Technology Data Exchange (ETDEWEB)

    Guaglio, G

    2005-12-15

    The energy stored in the Large Hadron Collider is unprecedented. The impact of the beam particles can cause severe damage on the superconductive magnets, resulting in significant downtime for repairing. The Beam Loss Monitors System (BLMS) detects the secondary particles shower of the lost beam particles and initiates the extraction of the beam before any serious damage to the equipment can occur. This thesis defines the BLMS specifications in term of reliability. The main goal is the design of a system minimizing both the probability to not detect a dangerous loss and the number of false alarms generated. The reliability theory and techniques utilized are described. The prediction of the hazard rates, the testing procedures, the Failure Modes Effects and Criticalities Analysis and the Fault Tree Analysis have been used to provide an estimation of the probability to damage a magnet, of the number of false alarms and of the number of generated warnings. The weakest components in the BLMS have been pointed out. The reliability figures of the BLMS have been calculated using a commercial software package (Isograph.). The effect of the variation of the parameters on the obtained results has been evaluated with a sensitivity analysis. The reliability model has been extended by the results of radiation tests. Design improvements, like redundant optical transmission, have been implemented in an iterative process. The proposed system is compliant with the reliability requirements. The model uncertainties are given by the limited knowledge of the thresholds levels of the superconductive magnets and of the locations of the losses along the ring. The implemented model allows modifications of the system, following the measuring of the hazard rates during the LHC life. It can also provide reference numbers to other accelerators which will implement similar technologies. (author)

  10. Electroweak interactions at LEP energies

    International Nuclear Information System (INIS)

    What determined the energies of LEP and the SLC? Essentially they were determined by the desire to produce the Z0 in e+e- collisions. Since the mass of the Z0 is of order 90 MeV we need electron and positron energies of at least 45 MeV in the collider. We can already produce Z0 at the SPS and Tevatron, so why was so much effort and money spent to produce them also at the new accelerators? The answer is that the e+e- collisions the Z0 particles are produced in the s channel, and are thus produced resonantly, and therefore copiously. We shall see that the resonance peak in e+e- → f bar f is several hundred times the cross section off peak. In the terminology introduced by the nuclear physicists looking for funding of high intensity 1 GeV machines, LEP is a Z0 factory. Using LEP we can study the properties of the Z0, and of the electroweak interactions, with a detail and precision never before possible. It is already possible, after only short runs at LEP to see clearly the effects of the radiative corrections in the electroweak interactions. It has been the that the electroweak interaction is now entering a stage equivalent to the heady days of the Lamb shift in QED. In this paper, the author shows how to calculate some of the processes that have been, will be and may be observed at these energies in the production and decay of the Z0. This paper calculates the decay rate for Z0 → f bar f, to exhibit the Z0 peak , and also calculate the forward-backward asymmetry in this process which permits an alternative measurement of the parameters of the interaction

  11. Design, Construction and Commissioning of the CMS Tracker at CERN and Proposed Improvements for Detectors at the Future International Linear Collider

    CERN Document Server

    Bergauer, T

    The CMS (Compact Muon Solenoid) detector is a huge particle physics experiment located at one of the four proton-proton interaction points of the Large Hadron Collider (LHC) at CERN, the European Organization for Nuclear Research (Geneva, Switzerland). With 27 km circumference it is the not only the largest particle accelerator in size, but with a center of mass energy of 2x7 TeV it will also set the world record in terms of energy. The inner tracking system of the CMS experiment has a diameter of 2.4 m and a length of 5.4 m and is representing the largest silicon tracker ever built. About 15,000 detector modules consisting of more than 24,000 silicon sensors create a silicon area of 206 m2 to detect charged particles from proton collisions. They are placed on a rigid carbon fibre structure in the center of the experiment, and have to operate reliably within a harsh radiation environment and the working conditions of a 3.8 Tesla solenoid magnetic field at -10 degree C temperature. This thesis was conducted ...

  12. Electromagnetic probes of a pure-glue initial state in nucleus-nucleus collisions at energies available at the CERN Large Hadron Collider

    Science.gov (United States)

    Vovchenko, V.; Karpenko, Iu. A.; Gorenstein, M. I.; Satarov, L. M.; Mishustin, I. N.; Kämpfer, B.; Stoecker, H.

    2016-08-01

    Partonic matter produced in the early stage of ultrarelativistic nucleus-nucleus collisions is assumed to be composed mainly of gluons, and quarks and antiquarks are produced at later times. To study the implications of such a scenario, the dynamical evolution of a chemically nonequilibrated system is described by ideal (2+1)-dimensional hydrodynamics with a time dependent (anti)quark fugacity. The equation of state interpolates linearly between the lattice data for the pure gluonic matter and the lattice data for the chemically equilibrated quark-gluon plasma. The spectra and elliptic flows of thermal dileptons and photons are calculated for central Pb+Pb collisions at the CERN Large Hadron Collider energy of √{sN N}=2.76 TeV. We test the sensitivity of the results to the choice of equilibration time, including also the case where the complete chemical equilibrium of partons is reached already at the initial stage. It is shown that a suppression of quarks at early times leads to a significant reduction of the yield of the thermal dileptons, but only to a rather modest suppression of the pT distribution of direct photons. It is demonstrated that an enhancement of photon and dilepton elliptic flows might serve as a promising signature of the pure-glue initial state.

  13. The Next Linear Collider: NLC2001

    Energy Technology Data Exchange (ETDEWEB)

    D. Burke et al.

    2002-01-14

    Recent studies in elementary particle physics have made the need for an e{sup +}e{sup -} linear collider able to reach energies of 500 GeV and above with high luminosity more compelling than ever [1]. Observations and measurements completed in the last five years at the SLC (SLAC), LEP (CERN), and the Tevatron (FNAL) can be explained only by the existence of at least one particle or interaction that has not yet been directly observed in experiment. The Higgs boson of the Standard Model could be that particle. The data point strongly to a mass for the Higgs boson that is just beyond the reach of existing colliders. This brings great urgency and excitement to the potential for discovery at the upgraded Tevatron early in this decade, and almost assures that later experiments at the LHC will find new physics. But the next generation of experiments to be mounted by the world-wide particle physics community must not only find this new physics, they must find out what it is. These experiments must also define the next important threshold in energy. The need is to understand physics at the TeV energy scale as well as the physics at the 100-GeV energy scale is now understood. This will require both the LHC and a companion linear electron-positron collider. A first Zeroth-Order Design Report (ZDR) [2] for a second-generation electron-positron linear collider, the Next Linear Collider (NLC), was published five years ago. The NLC design is based on a high-frequency room-temperature rf accelerator. Its goal is exploration of elementary particle physics at the TeV center-of-mass energy, while learning how to design and build colliders at still higher energies. Many advances in accelerator technologies and improvements in the design of the NLC have been made since 1996. This Report is a brief update of the ZDR.

  14. Proton-Λ correlation functions at energies available at the CERN Large Hadron Collider taking into account residual correlations

    Science.gov (United States)

    Shapoval, V. M.; Sinyukov, Yu. M.; Naboka, V. Yu.

    2015-10-01

    The theoretical analysis of the p ¯-Λ ⊕p -Λ ¯ correlation function in 10% most central Au+Au collisions at Relativistic Heavy Ion Collider (RHIC) energy √{sNN}=200 GeV shows that the contribution of residual correlations is a necessary factor for obtaining a satisfactory description of the experimental data. Neglecting the residual correlation effect leads to an unrealistically low source radius, about 2 times smaller than the corresponding value for p -Λ ⊕p ¯-Λ ¯ case, when one fits the experimental correlation function within Lednický-Lyuboshitz analytical model. Recently an approach that accounts effectively for residual correlations for the baryon-antibaryon correlation function was proposed, and a good RHIC data description was reached with the source radius extracted from the hydrokinetic model (HKM). The p ¯-Λ scattering length, as well as the parameters characterizing the residual correlation effect—annihilation dip amplitude and its inverse width—were extracted from the corresponding fit. In this paper we use these extracted values and simulated in HKM source functions for Pb+Pb collisions at the LHC energy √{sNN}=2.76 TeV to predict the corresponding p Λ and p Λ ¯ correlation functions.

  15. 2001 Report on the Next Linear Collider

    Energy Technology Data Exchange (ETDEWEB)

    Gronnberg, J; Breidenbach; Burke, D; Corlett, J; Dombeck, T; Markiewicz, T

    2001-08-28

    Recent studies in elementary particle physics have made the need for an e{sup +}e{sup -} linear collider able to reach energies of 500 GeV and above with high luminosity more compelling than ever [1]. Observations and measurements completed in the last five years at the SLC (SLAC), LEP (CERN), and the Tevatron (FNAL) can be explained only by the existence of at least one particle or interaction that has not yet been directly observed in experiment. The Higgs boson of the Standard Model could be that particle. The data point strongly to a mass for the Higgs boson that is just beyond the reach of existing colliders. This brings great urgency and excitement to the potential for discovery at the upgraded Tevatron early in this decade, and almost assures that later experiments at the LHC will find new physics. But the next generation of experiments to be mounted by the world-wide particle physics community must not only find this new physics, they must find out what it is. These experiments must also define the next important threshold in energy. The need is to understand physics at the TeV energy scale as well as the physics at the 100-GeV energy scale is now understood. This will require both the LHC and a companion linear electron-positron collider.

  16. Hadron collider physics at UCR

    International Nuclear Information System (INIS)

    This paper describes the research work in high energy physics by the group at the University of California, Riverside. Work has been divided between hadron collider physics and e+-e- collider physics, and theoretical work. The hadron effort has been heavily involved in the startup activities of the D-Zero detector, commissioning and ongoing redesign. The lepton collider work has included work on TPC/2γ at PEP and the OPAL detector at LEP, as well as efforts on hadron machines

  17. Study of Z Boson Pair Production and Search for Physics beyond Standard Model at LEP-II

    CERN Document Server

    Mohanty, G B

    2002-01-01

    The LEP collider at CERN, with its large data sample collected at energies that were never previously attained in e+e- collisions, is an ideal laboratory to test the predictions of the Standard Model (SM). One of the major areas to be explored at LEP is the self-interaction among the gauge bosons envisaged, due to the non-abelian nature of the SU(2)_LXU(1)_Y gauge group associated with the SM. The reaction e+e- -> ZZ, in particular, provides an ideal opportunity to test this theory by verifying that the anomalous couplings, V_ZZZ and V_ZZgamma, are absent at the tree level. Possible deviation from the SM expectation, in the form of a change in the measured Z-pair production cross section or a modification to the angular distribution of the Z bosons, would be a sign of new physics. Another strong motivation for studying this process is in connection with the production of the Higgs boson at LEP. The Higgs boson, the manifestation of spontaneous breaking of the underlying gauge symmetry, is responsible for gene...

  18. The large hadron collider and the super proton synchrotron at CERN as tools to generate warm dense matter and non-ideal plasmas

    International Nuclear Information System (INIS)

    The largest accelerator in the world, the Large Hadron Collider (LHC) at CERN, has entered into commissioning phase. It is expected that when this impressive machine will become fully operational, it will generate two counter rotating 7 TeV/c proton beams that will be made to collide, leading to an unprecedented luminosity of 1034 cm-2s-1. Total energy stored in each LHC beam is about 362 MJ, sufficient to melt 500 kg copper. Safety of operation is a very critical issue when working with such extremely powerful beams. It is important to know the consequences of an accidental release of the beam energy in order to design protection system for the equipment. For this purpose we have carried out extensive numerical simulations of the interaction of one full LHC beam with copper and graphite targets which are materials of practical importance. Our calculations have shown that the LHC protons will penetrate up to about 35 m in solid copper and 10 m in solid graphite. A very interesting outcome of this work is that the impact of the LHC beam on solid matter will generate Warm Dense Matter (WDM) and Strongly Coupled Plasmas (SCP). The beams for the LHC are pre-accelerated in the SPS (Super Proton Synchrotron) to 450 GeV/c and transferred to LHC via two beam lines. Several SPS cycles are required to fill the LHC, in one cycle a batch with up to 288 bunches can be accelerated. From the safety point of view it is also very important to study the damage caused to the equipment in case of an accident involving an uncontrolled release of the SPS beam. For this purpose we have also carried out detailed numerical simulations of the impact of the full SPS beam on solid copper and tungsten targets. These simulations have shown that the targets are severely damaged by the beam. It is also interesting to note that also in this case, a large part of the target material is converted into WDM and SCP. This study, therefore, shows that the LHC and the SPS have the potential to be used

  19. The Large Hadron Collider

    CERN Document Server

    Evans, Lyndon

    2012-01-01

    The construction of the Large Hadron Collider (LHC) has been a massive endeavour spanning almost 30 years from conception to commissioning. Building the machine with the highest possible energy (7 TeV) in the existing large electron–positron (LEP) collider tunnel of 27 km circumference and with a tunnel diameter of only 3.8 m has required considerable innovation. The first was the development of a two-in-one magnet, where the two rings are integrated into a single magnetic structure. This compact two-in-one structure was essential for the LHC owing to the limited space available in the existing LEP collider tunnel and the cost. The second was a bold move to the use of superfluid helium cooling on a massive scale, which was imposed by the need to achieve a high (8.3 T) magnetic field using an affordable Nb-Ti superconductor.

  20. LEP Shines Light on Dark Matter

    OpenAIRE

    Fox, Patrick J.; Harnik, Roni(Theoretical Physics Department, Fermilab, P.O. Box 500, Batavia, IL, 60510, U.S.A.); Kopp, Joachim; Tsai, Yuhsin

    2011-01-01

    Dark matter pair production at high energy colliders may leave observable signatures in the energy and momentum spectra of the objects recoiling against the dark matter. We use LEP data on mono-photon events with large missing energy to constrain the coupling of dark matter to electrons. Within a large class of models, our limits are complementary to and competitive with limits on dark matter annihilation and on WIMP-nucleon scattering from indirect and direct searches. Our limits, however, d...

  1. Thermalization, evolution, and observables at energies available at the CERN Large Hadron Collider in an integrated hydrokinetic model of A +A collisions

    Science.gov (United States)

    Naboka, V. Yu.; Karpenko, Iu. A.; Sinyukov, Yu. M.

    2016-02-01

    A further development of the evolutionary picture of A +A collisions, which we call the integrated hydrokinetic model (iHKM), is proposed. The model comprises a generator of the initial state GLISSANDO, prethermal dynamics of A +A collisions leading to thermalization, subsequent relativistic viscous hydrodynamic expansion of quark-gluon and hadron medium (vHLLE), its particlization, and finally the hadronic cascade ultrarelativistic QMD. We calculate midrapidity charged-particle multiplicities, pion, kaon, and antiproton spectra, charged-particle elliptic flows, and pion interferometry radii for Pb + Pb collisions at the energies available at the CERN Large Hadron Collider, √{s }=2.76 TeV, at different centralities. We find that the best description of the experimental data is reached when the initial states are attributed to the very small initial time 0.1 fm/c , the prethermal stage (thermalization process) lasts at least until 1 fm/c , and the shear viscosity at the hydrodynamic stage of the matter evolution has its minimal value, η /s =1/4 π . At the same time it is observed that the various momentum anisotropies of the initial states, different initial and relaxation times, as well as even a treatment of the prethermal stage within just viscous or ideal hydrodynamic approach, lead sometimes to worse but nevertheless similar results if the normalization of maximal initial energy density in most central events is adjusted to reproduce the final hadron multiplicity in each scenario. This can explain a good enough data description in numerous variants of hybrid models without a prethermal stage when the initial energy densities are defined up to a common factor.

  2. LEP superconducting cavity

    CERN Document Server

    1995-01-01

    Engineers work in a clean room on one of the superconducting cavities for the upgrade to the LEP accelerator, known as LEP-2. The use of superconductors allow higher electric fields to be produced so that higher beam energies can be reached.

  3. CAD for LEP

    CERN Multimedia

    1983-01-01

    A work station of the Computer-Aided Design system which was installed in 1982 to aid in the mechanics design for LEP. Visible on the screen is a design made for a pick-up for LEP. See Annual Report 1982 p. 79, Fig. 2.

  4. Review of LEP results

    CERN Document Server

    Parodi, F

    2001-01-01

    I present a review of the results obtained during 10 years of activity in b-physics at LEP. Special emphasis is put on measurements that attained precisions not even envisaged at the beginning of the LEP programme (V/sub ub/ and Delta m/sub s/). Finally the impact of these measurements on the CKM parameters determination is presented. (16 refs).

  5. 50 years of synchrotrons. Early synchrotrons in Britain, and early work for CERN. - The CERN synchrotrons. Lectures

    International Nuclear Information System (INIS)

    In the first report, 'Early synchrotrons in Britain, and early work for CERN', John Lawson gives an extended account of the material presented at the John Adams lecture, and at the same time a revised and shortened version of RAL report 97-011, which contains fuller archival references and notes. During the period covered by this report there was extensive work in Russia, where the principle of phase stability had been discovered in 1944 by Veksler. Unfortunately, all experimental work was kept secret until Veksler's talk at the first 'Atoms for Peace' conference at Geneva in August 1955. In the second lecture, 'The CERN Synchrotrons', Giorgio Brianti outlines the history of alternating-gradient synchrotrons from 1953/54 until today. In preparing this lecture he was confronted with a vast amount of material, while the time at his disposal was not even one minute per year, implying a time compression factor close to one million. Therefore, he had to exercise drastic choices, which led him to concentrate on CERN hadron synchrotrons and colliders and leave aside the Large Electron-Positron storage ring (LEP). Indeed, LEP was the subject of the John Adams Memorial Lecture in 1990, and it may be treated again in the future in connection with its energy upgrade. Even with these severe limitations, it was impossible to do justice to the number and variety of events and to the ingenuity of the people who have carved the history of CERN and of particle physics on the magnets, radiofrequency cavities, vacuum etc., and on the record performance of our machines. (orig./WL)

  6. CERN - Commission Européenne

    CERN Multimedia

    2009-01-01

    Rolf-Dieter HEUER, Director General of CERN visits Commissioner Janez POTOCNIK (BRUSSELS, 03/03/2009, Ref.62264) CERN LHC Inauguration : extracts from the CERN LHC (European Organization for Nuclear Research - Large Hadron Collider) Inauguration and statements (GENEVA, 21/10/2008, Ref.59811) Commissioner Viviane REDING's visit to CERN (GENEVA, recorded 28/10/2005, Ref.42185)

  7. VIdeo News Release : CERN sets date for first attempt at 7 TeV collisions in the LHC

    CERN Multimedia

    2010-01-01

    footage and interview of Mike Lamont, leader of the Operation Group . Geneva, 23 March 2010. With beams routinely circulating in the Large Hadron Collider at 3.5 TeV, the highest energy yet achieved in a particle accelerator, CERN has set the date for the start of the LHC research programme. The first attempt for collisions at 7 TeV (3.5 TeV per beam) is scheduled for 30 March. “The LHC is not a turnkey machine,” said CERN Director General Rolf Heuer. “The machine is working well, but we’re still very much in a commissioning phase and we have to recognize that the first attempt to collide is precisely that. It may take hours or even days to get collisions.” The last time CERN switched on a major new research machine, the Large Electron Positron collider, LEP, in 1989 it took three days from the first attempt to collide beams to the first recorded collisions. The current LHC run began on 20 November 2009, with the first circulating beam at 0.45 TeV. Milestones were quick to follow, with twin circulat...

  8. The history of the LEP proposal

    International Nuclear Information System (INIS)

    Following recommendations by ECFA, the European Committee for Future Accelerators, that the next major European high energy facility should be a large electron positron collider, about 400 physicists and engineers from the 12 CERN member nations have been contributing to preparatory work as members of working groups. In particular, design and feasibility studies have been issued for (a) a 100 GeV per beam collider with a 51.5 km circumference, (b) a 70 GeV per beam collider with a 22.2 km circumference and (c) an 86 GeV per beam collider with a 30.6 km circumference. It is now proposed that the design (c) as discussed in the so-called 'Pink Book' should be used and that the accelerator should be built adjacent to CERN Meyrin. (U.K.)

  9. UK committee to push for CERN budget cuts

    CERN Document Server

    Walgate, Robert

    1985-01-01

    A committee set up to assess Britain's continued membership of CERN will suggest that spending on high energy physics should be reduced. Germany and France also believe that CERN could survive cuts but the Director General Professor Schopper defended the CERN budget saying that increased spending was needed to increase the energy of LEP and to fulfill pension requirements (1 page)

  10. Heavy quark physics in ep collisions at LEP+LHC

    International Nuclear Information System (INIS)

    We study electroweak production of heavy quarks - charm, beauty, and top - in deep inelastic electron-proton collisions at the proposed LEP+LHC collider at CERN. The assumed energy for the collisions is Ee=50 GeV, Ep=8000 GeV, providing an ep center of mass energy, √s≅1.26 TeV. We invoke the boson-gluon fusion model to estimate theoretical cross sections and distributions for the heavy quarks. Higher order QCD corrections are only approximately taken into account, by assuming a (normalization) K-factor of 2 for the charm and beauty quark production rates and incorporating the parton shower cascades. With these assumptions and the parameterization of Eichten et al. for the structure functions (EHLQ, set 1), we find the following cross sections: σ(ep→c+X)≅O(3 μb), σ(ep→b+X)≅O(40 nb), and σ(ep→t+X)≅4 pb for mt=120 GeV, decreasing to 0.5 pb for mt=250 GeV. These cross sections would provide O(6x109) charmed hadrons, O(8x107) beauty hadrons, and O(103) top hadrons, for an integrated ep luminosity of 1000 pb-1. The heavy quark rates in ep collisions are considerably smaller than the corresponding rates in pp collisions at LHC, with √s=16 TeV. This gives a clear advantage to pp collisions for top searches. However, for the charmed and beauty quarks only a tiny fraction of the cross sections in p+p→Q+X can be triggered in comparison to the corresponding cross sections in e+p→Q+X, resulting in comparable number of measured heavy quark events in the ep and pp mode. We sketch the energy-momentum profile of heavy quark events in ep collisions and illustrate the kind of analyses that experiments at the LEP+LHC collider would undertake to quantitatively study heavy quark physics. In particular, prospects of measuring the particle-antiparticle mixing parameter xs=ΔM/Γ for the Bs0-anti Bs0 meson system are evaluated, and search strategies for the top quark in ep collisions are presented. (orig.)

  11. The evolution of the LEP logging database

    CERN Document Server

    Billen, R

    1995-01-01

    In January 1992, a project was started to create a system, using an on-line ORACLE database, to allow logging of a multitude of data on the Large Electron Positron Collider (LEP). The aim of this project was to log particle beam characteristics, physics parameters, hardware settings and environmental conditions. Storing and keeping track of this heterogeneous data for a period of at least one year would permit a better understanding of the behavior of the fairly new LEP Collider.After using the logging system for almost four years, nearly three years of which in full operation, the reliability and performance has been proved, endorsing the design of the database and surrounding software. Moreover, the large number of users of the logging database and the huge amount of new requests for data logging shows the high activity and usefulness of this system. Furthermore, in the context of the 1993 and 1995 energy scans, the logged data turns out to be indispensable for thorough monitoring of the LEP beam energy, wh...

  12. Supersymmetric particles at LEP

    International Nuclear Information System (INIS)

    The authors examine whether the supersymmetrization of nature at a mass scale up to 100 GeV can be confirmed or excluded by experiments with LEP. They review the qualitative features of the spectroscopy suggested by supersymmetric theories. Then they discuss possible production rates and means of detection of these particles at LEP. In this framework they make some remarks about other projects for future high energy physics machines which can be used for the study of supersymmetric phenomena. (HSI)

  13. Asymmetric collider

    International Nuclear Information System (INIS)

    The study of CP violation in beauty decay is one of the key challenges facing high energy physics. Much work has not yielded a definitive answer how this study might best be performed. However, one clear conclusion is that new accelerator facilities are needed. Proposals include experiments at asymmetric electron-positron colliders and in fixed-target and collider modes at LHC and SSC. Fixed-target and collider experiments at existing accelerators, while they might succeed in a first observation of the effect, will not be adequate to study it thoroughly. Giomataris has emphasized the potential of a new approach to the study of beauty CP violation: the asymmetric proton collider. Such a collider might be realized by the construction of a small storage ring intersecting an existing or soon-to-exist large synchrotron, or by arranging collisions between a large synchrotron and its injector. An experiment at such a collider can combine the advantages of fixed-target-like spectrometer geometry, facilitating triggering, particle identification and the instrumentation of a large acceptance, while the increased √s can provide a factor > 100 increase in beauty-production cross section compared to Tevatron or HERA fixed-target. Beams crossing at a non-zero angle can provide a small interaction region, permitting a first-level decay-vertex trigger to be implemented. To achieve large √s with a large Lorentz boost and high luminosity, the most favorable venue is the high-energy booster (HEB) at the SSC Laboratory, though the CERN SPS and Fermilab Tevatron are also worth considering

  14. The trigger system of the OPAL experiment at LEP

    Energy Technology Data Exchange (ETDEWEB)

    Arignon, M.; Ball, A.H.; Bell, K.W.; Bramhall, M.; Braun, A.; Carter, A.A.; Carter, J.R.; Charlton, D.G.; Dittmar, M.; Farthouat, P.; Feyt, J.; Gao, H.; Gary, J.W.; Gillies, J.D.; Greiner, C.; Hammarstroem, R.; Hart, J.; Heuer, R.D.; Hill, J.C.; Hillier, S.J.; Hilse, T.; Humbert, R.; Jaroslawski, S.; Joos, D.; Jovanovic, P.; Kawamoto, T.; Kellogg, R.G.; Kobayashi, T.; Le Du, P.; Levinson, L.J.; Loebinger, F.K.; MacBeth, A.A.; Mikenberg, G.; Milborrow, R.; Pawley, S.J.; Penton, A.; Pritchard, T.W.; Quast, G.; Rieth, G.; Roach, C.M.; Runge, K.; Schaile, O.; Scherer, D.; Schuler, G.; Schwarz, J.; Springer, R.W.; Takeda, H.; Virtue, C.J.; Wagner, A.; Ward, D.R.; Watkins, P.M.; Webel, M.; Weber, C.; Weymann, M.; Wilson, G.W.; Wilson, J.A. (School of Physics and Space Research, Univ. of Birmingham (United Kingdom) Dept. of Physics, Univ. of California, Riverside, CA (United States) Cavendish Lab., Cambridge (United Kingdom) CERN, European Organisation for Particle Physics, Geneva (Switzerla

    1992-03-01

    This paper describes the trigger system of the OPAL detector at the e{sup +}e{sup -} collider LEP and its performance during the first year of data taking. A high level of redundancy and fine detector segmentation at the trigger level led to a high efficiency for all considered physics reactions while the trigger rates were kept low. (orig.).

  15. Exclusive Channels in Photon-Photon Collisions at LEP

    OpenAIRE

    Braccini, S.

    2002-01-01

    The study of exclusive channels in photon-photon collisions at e+e- colliders allows to investigate the structure and the properties of hadrons in a very clean experimental environment. A concise review of the most recent results obtained at LEP is presented.

  16. CERN'S Fire and Rescue Group Gets New Ambulance

    CERN Multimedia

    2000-01-01

    The ambulance is to replace another based on the off-road vehicle design which was originally acquired for the civil engineering phase of LEP construction. Just one figure, in 1999, the CERN ambulance was called out 195 times.

  17. Plascore receives awards from CERN

    CERN Multimedia

    2002-01-01

    Plascore recently was awarded two honors from CERN, European High Energy Physics Lab, for its involvement in the manufacture of Thermoplastic Honeycomb panels for their large superconducting super collider (1/2 page).

  18. Collider limits on dark matter

    OpenAIRE

    Kopp, Joachim

    2011-01-01

    Dark matter pair production at high energy colliders may leave observable signatures in the energy and momentum spectra of the objects recoiling against the dark matter. We discuss signatures of Dark Matter in the jets + missing energy and photon + missing energy channels at the Tevatron and at LEP. Working in a largely model-independent effective theory framework, we can convert the collider bounds into constraints on the dark matter-nucleon scattering cross section and on the dark matter an...

  19. The W bosons physics and four-fermion processes in the LEP2 experiments - Monte Carlo approach

    International Nuclear Information System (INIS)

    The computer codes LoralW and YFSWW for Monte Carlo simulation of the four-fermion processes is presented. These programs are dedicated for prediction of W bosons pairs production and theirs decay at LEP experiments at CERN

  20. Industrial services at CERN

    CERN Multimedia

    2002-01-01

    The Bulletin looks at industrial services contracts and the real impact of the cost reductions at CERN. The level of industrial services contracts varies from one phase to another. For example, during the dismantling of LEP (photo) it rose substiantially to fall again at the end of dismantling. Industrial services contracts are an important resource for CERN. The level and nature of such contracts changes according to the phase of operation of the Laboratory. A construction phase, as for the LHC, requires a higher level of industrial services contracts compared with a period of normal running. During the operation of LEP, industrial services contracts were thus maintained at a level of 120 MCHF per year. The level rose to 156 MCHF in 2001 to include contracts awarded for dismantling LEP, and fell to about 144 MCHF in 2002 when the dismantling was complete. During the whole LHC construction period, up to 2007, industrial services spending will be stable in the range 135-140 MCHF per year. For the running pe...

  1. People and things. CERN Courier, May 1990, v.30(4)

    International Nuclear Information System (INIS)

    The article reports on achievements of various people, staff changes and position opportunities within the CERN organization and contains news updates on upcoming or past events: ; Implications for 'dark matter' - the invisible mass of the Universe - were a talking point at the recent astrophysics workshop in the Moriond series, and a focus of the meeting 'LEP and the Universe' at CERN. ; This year's DESY Theory Workshop from 1-3 October will be on 'Waiting for the Top Quark'. ; To explore in detail and update the physics possibilities for the Large Hadron Collider (LHC) project at CERN, the European Committee for Future Accelerators (ECFA) is now preparing for an LHC Workshop to be held in Aachen from 4-9 October. ; An important milestone for the HERA electron-proton collider being built at the German DESY Laboratory in Hamburg was passed early in April when the turbines of the HERA refrigeration plant were switched on to cool down the first octant of the superconducting proton ring

  2. Geodesy and metrology of the LEP

    International Nuclear Information System (INIS)

    The accurate installation of an accelerator of 8,500 m diameter requires the most refined geodetic techniques. The instrumentation in use incorporates not only lasers and eventually satellites, but also the simple nylon wire. Over 20,000 measurement will be made to install to within 0.1 mm the 5,000 fonctional elements of the LEP machine (Large Electron-Positron Collider). This work will be controlled and checked by portable computers. Each instrument will be automatic and will contain a miniature micro-computer (on a ''flexible-rigid'' card)

  3. The collider of the future?

    CERN Multimedia

    2009-01-01

    Why are two studies for one linear collider being conducted in parallel? This is far from a duplication of effort or a waste of resources, since the two studies reflect a complementary strategy aimed at providing the best technology for future physics. On Friday 12 June CERN hosted the first joint meeting between CLIC, ILC and the CERN management.

  4. CERN confirms LHC schedule

    CERN Multimedia

    2003-01-01

    The CERN Council held its 125th session under the chairmanship of Professor Maurice Bourquin. Highlights of the meeting included confirmation that the Large Hadron Collider (LHC) and its detectors are on schedule for a 2007 start-up, and that the LHC computing grid (LCG) project is about to reach a major milestone (1 page).

  5. Inter-string Bose-Einstein correlations in hadronic Z decays using the L3 detector at LEP

    CERN Document Server

    Wang, Qin

    2008-01-01

    Bose-Einstein Correlations (BEC) of identical bosons can be used for the femtoscopy of the pro- duction properties of bosons in high energy particle collisions. This quantum mechanical BEC effect is a direct consequence of the symmetrization of the wave function of a boson system and is frequently used on photons in Astophysics to measure the angular size and other properties of distant stars. In particle collisions, the effect can be observed experimentally as an enhancement of the production of identical bosons with small four-momentum difference Q relative to a production that would occur in a world without Bose-Einstein statistics. In this thesis, BEC are studied between identical pions produced in electron-positron collisions at a center-of-mass energy of 91 GeV in the LEP e+ e− Collider of CERN, near Geneva. The final-state particles of these collisions are detected in the detector of the L3 experiment, which is positioned at one of the four intersections of LEP. According to the present picture of bo...

  6. LEP dismantling starts

    CERN Multimedia

    2000-01-01

    Since the end of November, various teams have been getting stuck into dismantling the LEP accelerator and its four experiments. After making the installations safe, the dismantling and removal of 40,000 tonnes of equipment is underway. Down in the tunnel, it is a solemn moment. It is 10 o'clock on 13 December and Daniel Regin, one of those heading the dismantling work, moves in on a magnet, armed with a hydraulic machine. Surrounded by teams gathered there for a course in dismantling, he makes the first cut into LEP. The great deconstruction has begun. In little over than a year, the accelerator will have been cleared away to make room for its successor, the LHC. The start of the operation goes back to 27 November. Because before setting about the machine with hydraulic shears and monkey wrenches, LEP had first to be made safe - it was important to make sure the machine could be taken apart without risk. All the SPS beam injection systems to LEP were cut off. The fluids used for cooling the magnets and superc...

  7. ZZ production at LEP

    CERN Document Server

    Sánchez-Álvaro, E

    2000-01-01

    The process e/sup +/e/sup -/ to ZZ is studied at LEP at center-of- mass energies near 183 and 189 GeV. Cross sections are measured and found to be in agreement with the standard model expectations. Limits on anomalous ZZZ and ZZ gamma couplings are set. (6 refs).

  8. LEP vacuum chamber, prototype

    CERN Multimedia

    1983-01-01

    Final prototype for the LEP vacuum chamber, see 8305170 for more details. Here we see the strips of the NEG pump, providing "distributed pumping". The strips are made from a Zr-Ti-Fe alloy. By passing an electrical current, they were heated to 700 deg C.

  9. Superconducting cavities for LEP

    CERN Multimedia

    1983-01-01

    Above: a 350 MHz superconducting accelerating cavity in niobium of the type envisaged for accelerating electrons and positrons in later phases of LEP. Below: a small 1 GHz cavity used for investigating the surface problems of superconducting niobium. Albert Insomby stays on the right. See Annual Report 1983 p. 51.

  10. LEP Vacuum Chamber

    CERN Multimedia

    1983-01-01

    This is a cut-out of a LEP vacuum chamber for dipole magnets showing the beam channel and the pumping channel with the getter (NEG) strip and its insulating supports. A water pipe connected to the cooling channel can also be seen at the back.The lead radiation shield lining is also shown. See also 8305563X.

  11. Hadron collider physics at UCR

    Energy Technology Data Exchange (ETDEWEB)

    Kernan, A.; Shen, B.C.

    1997-07-01

    This paper describes the research work in high energy physics by the group at the University of California, Riverside. Work has been divided between hadron collider physics and e{sup +}-e{sup {minus}} collider physics, and theoretical work. The hadron effort has been heavily involved in the startup activities of the D-Zero detector, commissioning and ongoing redesign. The lepton collider work has included work on TPC/2{gamma} at PEP and the OPAL detector at LEP, as well as efforts on hadron machines.

  12. Large Hadron Collider au CERN: des big bangs en série sous le contrôle de WorldFIP

    CERN Multimedia

    2007-01-01

    Thanks to WorlsFIP, associated with a GPS system, CERN is able to synchronize most of the LHC equipments, to drive the magnetic field of giant experiments, to put back automatically the clock at the hour and date events with a precision better than 10 mu s. (1 page)

  13. CREATIVE COLLISIONS: ARTS @CERN

    CERN Document Server

    CERN. Geneva

    2012-01-01

    In 2000, CERN hosted Signatures of the Invisible – one of the landmark initiatives in arts and science. In 2012, CERN is now initiating its own science/arts programme Collide@CERN in different arts disciplines. The first of these is in digital arts, and the international competition to find the winning artist is called the Prix Ars Electronica Collide@CERN. It was announced September 2011 at CERN’s first collaboration with an international arts festival – Ars Electronica in Linz. The competition attracted over 395 entries from 40 countries around the world. The winning artist, Julius Von Bismarck, will begin his two month residency here at CERN next month. Ariane Koek who leads on this initiative, discusses the residency programme, as well as the background about Art@CERN. History has shown that particle physics and the arts are great inspiration partners. The publication of the paper by Max Planck which gave birth to quantum mechanics as well as those by Einstein, heavily influenced some of the grea...

  14. Monitoring and control of the muon detector in the L3 experiment at LEP

    International Nuclear Information System (INIS)

    In this report the monitoring system of the muon spectrometer of the L3 detector in LEP at CERN is presented. The system is based on a network of VME's using the OS9 operating system. The design guiding lines and the present system configuration are described both from the hardware and the software point of view. In addition, the report contains the description of the monitored parameters showing typical data collected durintg the first months of LEP operation. (Author)

  15. Large Hadron Collider

    CERN Multimedia

    2007-01-01

    "In the spring 2008, the Large Hadron Collider (LHC) machine at CERN (the European Particle Physics laboratory) will be switched on for the first time. The huge machine is housed in a circular tunnel, 27 km long, excavated deep under the French-Swiss border near Geneva." (1,5 page)

  16. Tevatron's complex collider cousins

    CERN Multimedia

    Fischer, W

    2004-01-01

    Letter referring to Schwarzschild's story "Disappointing performance and tight budgets confront Fermilab with tough decisions" and contesting that the Tevatron is not the most complex accelerator operating. They use the examples of CERN's SPS collider, HERA at DESY and the RHIC at Brookhaven (1/4 page)

  17. The Large Hadron Collider

    CERN Multimedia

    Wright, Alison

    2007-01-01

    "We are on the threshold of a new era in particle-physics research. In 2008, the Large Hadron Collider (LHC) - the hightest-energy accelerator ever built - will come into operation at CERN, the European labortory that straddles the French-Swiss border near Geneva." (1/2 page)

  18. Tau anomalous magnetic moment in γγ colliders

    Science.gov (United States)

    Peressutti, Javier; Sampayo, Oscar A.

    2012-08-01

    We investigate the possibility of setting model independent limits for a nonstandard anomalous magnetic moment aτNP of the tau lepton, in future γγ colliders based on Compton backscattering. For a hypothetical collider we find that, at various levels of confidence, the limits for aτNP could be improved, compared to previous studies based on LEP1, LEP2 and SLD data. We show the results for a realistic range of the center of mass energy of the e+e- collider. As a more direct application, we also present the results of the simulation for the photon collider at the TESLA project.

  19. CERN: le Mondial de la particule

    CERN Multimedia

    Favier, R

    1998-01-01

    Avec le LEP (acc\\’{e}l\\’{e}rateur de particules), le CERN est devenu le v\\’{e}ritable phare de la science europ\\’{e}enne. Notamment pour la physique des particules. Riche de multiples exp\\’{e}riences r\\’{e}ussies, mais aussi de quelques prix Nobel, le CERN est en train de vivre une nouvelle aventure scientifique, en lan

  20. Experiments at CERN in 1984

    International Nuclear Information System (INIS)

    This book is a compilation of the current experimental program at CERN. The experiments listed are being performed at one of the following machines: the Super Proton Synchrotron (SPS), the Proton Synchrotron (PS) and the Synchro-Cyclotron (SC). The Intersecting Storage Rings (ISR) have ceased functioning early this year. The four approved experiments to be done by means of the Large Electron Positron machine (LEP) are also listed. (orig./HSI)

  1. Ex / Noise / CERN / Deerhoof

    CERN Multimedia

    CERN, SM18,

    2015-01-01

    Indie rockers Deerhoof battled with the noise of CERN’s magnet test facilities on 30 August 2015. The band visited CERN at the invitation of ATLAS physicist James Beacham, whose pilot project Ex/Noise/CERN collides experimental music artists with experimental particle physics. Credits: -Producer- CERN Video Productions James Beacham François Briard -Director- Noemi Caraban -Camera- Yann Krajewski Piotr Traczyk Noemi Caraban -Crane operator- Antonio Henrique Jorge-Costa -Live recording at CERN- Mixing at Rec studio/Geneva By Serge Morattel -Infography- Daniel Dominguez Noemi Caraban -Deerhoof- John Dieterich Satomi Matsuzaki Ed Rodriguez Greg Saunier w/Deron Pulley SPECIAL THANKS TO: Michal Strychalski Marta Bajko Maryline Charrondiere Luca Bottura Christian Giloux Rodrigue Faes Mariane Catallon Georgina Hobgen Hailey Reissman Marine Bass

  2. LEP Magnets Get a Second Lease of Life

    CERN Multimedia

    2001-01-01

    Removed one minute, recycled the next! Around 900 yokes from the LEP dipole magnets have been re-used as building material. 906 yokes from the LEP dipole magnets have been incorporated in the foundations of the new Building 954, where they have been used to create the underfloor space and reinforcements. The recycling of LEP is already under way. Over half of CERN's accelerator has been dismantled so far, and parts of its magnets are already beginning a new life: since 16 May, some of the LEP dipole magnet yokes have been re-used as building material. The dipole yokes, the only ones of their kind, are made up of steel plates and layers of concrete sandwiched together, thus forming blocks of reinforced concrete. It would be a painstaking task to separate the basic materials for re-use, which led to the idea of using the yokes intact as reinforcements. 906 LEP yokes have gone into the foundations of the brand-new Building 954 on the Prévessin site. They have been used to build the underfloor space ...

  3. COLLIDE Pro Helvetia Award

    CERN Multimedia

    2016-01-01

    The COLLIDE Pro Helvetia Award is run in partnership with Pro Helvetia, giving the opportunity to Swiss artists to do research at CERN for three months.   From left to right: Laura Perrenoud, Marc Dubois and Simon de Diesbach. The photo shows their VR Project, +2199. Fragment.In are the winning artists of COLLIDE Pro Helvetia. They came to CERN for two months in 2015, and will now continue their last month in the laboratory. Fragment.In is a Swiss based interaction design studio. They create innovative projects, interactive installations, video and game design. Read more about COLLIDE here.

  4. accelerating cavity from LEP

    CERN Multimedia

    This is an accelerating cavity from LEP, with a layer of niobium on the inside. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment. These challenging requirements pushed European industry to new achievements. 256 of these cavities are now used in LEP to double the energy of the particle beams.

  5. UX-15 Reaches LEP

    CERN Multimedia

    2001-01-01

    The creation of the world's largest sandstone cavern, not a small feat! At the bottom, cave-in preventing steel mesh can be seen clinging to the top of the tunnel. The digging of UX-15, the cavern that will house ATLAS, reached the upper ceiling of LEP on October 10th. The breakthrough which took place nearly 100 metres underground occurred precisely on schedule and exactly as planned. But much caution was taken beforehand to make the LEP breakthrough clean and safe. To prevent the possibility of cave-ins in the side tunnels that will eventually be attached to the completed UX-15 cavern, reinforcing steel mesh was fixed into the walls with bolts. Obviously no people were allowed in the LEP tunnels below UX-15 as the breakthrough occurred. The area was completely evacuated and fences were put into place to keep all personnel out. However, while personnel were being kept out of the tunnels below, this has been anything but the case for the work taking place up above. With the creation of the world's largest...

  6. Challenges in future linear colliders

    CERN Document Server

    Chattopadhyay, S

    2002-01-01

    For decades, electron-positron colliders have been complementing proton-proton colliders. But the circular LEP, the largest e/sup -/e /sup +/ collider, represented an energy limit beyond which energy losses to synchrotron radiation necessitate moving to e/sup -/e/sup + / linear colliders (LCs), thereby raising new challenges for accelerator builders. Japanese-American, German, and European collaborations have presented options for the "Future Linear Collider " (FLC). Key accelerator issues for any FLC option are the achievement of high enough energy and luminosity. Damping rings, taking advantage of the phenomenon of synchrotron radiation, have been developed as the means for decreasing beam size, which is crucial for ensuring a sufficiently high rate of particle-particle collisions. Related challenges are alignment and stability in an environment where even minute ground motion can disrupt performance, and the ability to monitor beam size. The technical challenges exist within a wider context of socioeconomi...

  7. Spectra of identified hadrons in Pb-Pb collisions at 2.76 TeV at the CERN Large Hadron Collider

    International Nuclear Information System (INIS)

    The transverse-momentum distributions of identified hadrons produced in Pb-Pb collisions at the Large Hadron Collider (LHC) are studied in the low and intermediate range for pTT∼3 GeV/c. A substantial portion of the jet energy is found to be lost to the dense medium before the partons emerge at the surface to undergo hadronization by recombination.

  8. Multiplicities and correlations at LEP

    CERN Document Server

    Sarkisyan-Grinbaum, E

    2002-01-01

    A brief review on recent charge multiplicity and correlation measurements at LEP is given. The measurements of unbiased gluon jet multiplicity are discussed. Recent results on charged particle Bose- Einstein and Fermi-Dirac correlations at LEP1. are reported. New results on two-particle correlations of neutral pions are given. Correlations of more than two particles (high-order correlations) obtained using different methods are performed. Recent Bose-Einstein correlation measurements at LEP2 are discussed. (13 refs).

  9. The "Silicon Wheel" prototype for the barrel of the silicon tracker deep inside the CMS detector at CERN'S future LHC proton collider

    CERN Multimedia

    Laurent Guiraud

    1997-01-01

    Elements on a specially designed structure will track the emerging particles close to the beam pipe. The supporting structure is made out of special carbon fibre discs holding 112 detector modules (448 individual silicon detectors). The modules are arranged to provide three detection points per track and are distributed in seven layers on a spiral geometry to leave enough room for cables, cooling tubes, etc. The inner radius of the wheel is 20.5 cm; the overall diameter is 80 The prototype is a combined CMS silicon community effort; the main participating institutions were: Aachen (Germany), Bari (Italy), CERN, Florence (Italy), Imperial College (UK), Oulu (Finland), Padova, Perugia, Pisa (Italy), Rutherford Laboratory

  10. Circular Higgs Factories: LEP3, TLEP and SAPPHiRE

    CERN Document Server

    Zimmermann, F

    2012-01-01

    In 2012 two LHC experiments have discovered a new particle with a mass around 125 GeV, which might be the scalar Higgs boson of the Standard Model. This particle could be produced in large numbers for precision studies by an e+e− collider operating near the ZH threshold at a beam energy of 120 GeV or, in the s-channel, by a gamma-gamma collider with primary electron beam energies of 80 GeV. In this seminar I discuss tentative design parameters, novel concepts and accelerator-physics challenges for two circular e+e− Higgs-factory collidersLEP3 and TLEP – and for a gamma-gamma Higgs-factory collider based on a recirculating SC electron linac – SAPPHiRE. LEP3, installed in the existing 27-km LHC tunnel, and TLEP, in a new 80-km long tunnel, require – in addition to the collider ring – a fast cycling accelerator ring for quasi-continuous top-up injection to compensate the short beam lifetime due to radiative Bhabha scattering at luminosities above 1e34 cm-2s-1. In addition, a large momentum apert...

  11. Jets and decays of resonances: Two mechanisms responsible for reduction of elliptic flow at the CERN Large Hadron Collider (LHC) and restoration of constituent quark scaling

    International Nuclear Information System (INIS)

    The formation and evolution of the elliptic flow pattern in Pb+Pb collisions at √(s)=5.5A TeV and in Au+Au collisions at √(s)=200A GeV are analyzed for different hadron species within the framework of the HYDJET++ Monte Carlo model. The model contains both hydrodynamic state and jets, thus allowing for a study of the interplay between the soft and hard processes. It is found that jets terminate the rise of the elliptic flow with increasing transverse momentum. Since jets are more influential at the Large Hadron Collider (LHC) than at the Relativistic Heavy Ion Collider (RHIC), the elliptic flow at LHC should be weaker than that at RHIC. The influence of resonance decays on particle elliptic flow is also investigated. These final state interactions enhance the low-pT part of the v2 of pions and light baryons and work toward the fulfillment of idealized constituent quark scaling.

  12. Logistics of LEP installation

    International Nuclear Information System (INIS)

    The size of the LEP project, coupled with the tight construction schedules, calls for organized planning, logistics, monitoring and control. This is being carried out at present using tools such as ORACLE the Relational Database Management System, running on a VAX cluster for data storage and transfer, micro-computers for on-site follow-up, and PC's running Professional ORACLE, DOS and XENIX linked to a communications network to receive data feedback concerning transport and handling means. Following over 2 years of installations, this paper presents the methods used for the logistics of installation and their results

  13. Proton-antiproton collider physics

    CERN Document Server

    Altarelli, Guido

    1989-01-01

    This volume reviews the physics studied at the CERN proton-antiproton collider during its first phase of operation, from the first physics run in 1981 to the last one at the end of 1985. The volume consists of a series of review articles written by physicists who are actively involved with the collider research program. The first article describes the proton-antiproton collider facility itself, including the antiproton source and its principle of operation based on stochastic cooling. The subsequent six articles deal with the various physics subjects studied at the collider. Each article descr

  14. Scenarios for physics at LEP

    International Nuclear Information System (INIS)

    The author states his views regarding the importance of the experiments made possible if LEP is built. The main contribution of the LEP will be to understanding the physics of leptons, quarks and quantum chromodynamics. The author suggests the directions in which the new results might lead. (W.D.L.)

  15. Controls for the vacuum system of LEP

    International Nuclear Information System (INIS)

    The very large size (27-km circumference) of LEP (CERN Large Electron Positron storage ring) makes it mandatory to provide extensive remote control for installation, commissioning, and operation. The control facilities will be available both at fixed locations and in the form of mobile consoles which will follow the installation teams. All operations must be accessible to vacuum technicians, who may have little or no computing knowledge. Therefore, menu driven consoles, using a screen and light pen, will be made available to the operators. The large number of pumps, gauges, and valves makes it necessary to find solutions to reduce the cabling costs. An original way of powering the sputter ion pumps uses a single power supply and cable for up to eight pumps, yet allows individual current monitoring for each pump. An ionization gauge power supply for eight heads is economical and saves rack space by multiplexing the ion currents while powering and regulating continuously all filaments. All power supplies must be integrated in the general control system of the LEP machine. This is done by using so-called intelligent equipment controllers, which exchange messages with the main control room by a network of multidrop buses. A sophisticated data base management system is required in order to keep track of the numerous items connected to the vacuum system

  16. Physics at LEP2. Vol. 1

    International Nuclear Information System (INIS)

    This is the final report of the Workshop on Physics at LEP2, held at CERN during 1995. The first part of vol. 1 is devoted to aspects of machine physics of particular relevance to experiments, including the energy, luminosity and interaction regions, as well as the measurement of beam energy. The second part of vol. 1 is a relatively concise, but fairly complete, handbook on the physics of e+e- annihilation above the WW threshold and up to √s∼200 GeV. It contains discussions on WW cross-sections and distributions, W mass determination, Standard Model processes, QCD and gamma-gamma physics, as well as aspects of discovery physics, such as Higgs, new particle searches, triple gauge boson couplings and Z'. The second volume contains a review of the existing Monte Carlo generators for LEP2 physics. These include generators for WW physics, QCD and gamma-gamma processes, Bhabha scattering and discovery physics. A special effort was made to co-ordinate the different parts, with a view to achieving a systematic and balanced review of the subject, rather than just publishing a collection of separate contributions. (orig.)

  17. Physics at LEP2. Vol. 2

    International Nuclear Information System (INIS)

    This is final report of the Workshop on Physics at LEP2, held at CERN during 1995. The first part of vol. 1 is devoted to aspects of machine physics of particular relevance to experiments, including the energy, luminosity and interaction regions, as well as the measurement of beam energy. The second part of vol. 1 is a relatively concise, but fairly complete, handbook on the physics of e+e- annihilation above the WW threshold and up to √s∼200 GeV. It contains discussions on WW cross-sections and distributions, W mass determination, Standard Model processes, QCD and gamma-gamma physics, as well as aspects of discovery physics, such as Higgs, new particle searches, triple gauge boson couplings and Z'. The second volume contains a review of the existing Monte Carlo generators for LEP2 physics. These include generators for WW physics, QCD and gamma-gamma processes, Bhabha scattering and discovery physics. A special effort was made to co-ordinate the different parts, with a view to achieving a systematic and balanced review of the subject, rather than just publishing a collection of separate contributions. (orig.)

  18. Realization of the LEP power converters

    International Nuclear Information System (INIS)

    After a phase of intensive and detailed preparation, which included preliminary inquiries to a wide variety of firms, more than forty contracts and large orders were placed with industry. They cover the power part of the converters for the magnet system, the RF klystrons and the vacuum pumps as well as the electronics for the supervision, control and local intelligence for these high-precision equipments. The first deliveries of the series production started in the second half of 1986 and by the end of 1987 most of the high-power units for the magnet system have been delivered to CERN. After thorough tests they are being installed in the LEP equipment buildings. This includes all the equipment necessary for the injection tests into LEP octant 1 to 2, scheduled for July '88. This paper reports that the tests on the prototype 100 kV, 40 A converter for the RF klystrons were successfully terminated with a full power run on the RF test string. The first sets of the series units are being delivered, tested and installed. An important aspect for obtaining high reliability lies in the automatic test procedures which are rigorously carried out, starting at the module level and ending at the complete equipment

  19. Design study of the large hadron electron collider and a rapid cycling synchrotron as alternative to the PS booster upgrade at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Fitterer, Miriam

    2013-02-22

    With the Large Hadron Collider (LHC) the exploration of particle physics at center of mass energies at the TeV scale has begun. To extend the discovery potential of the LHC, a major upgrade is foreseen around 2020 of the LHC itself and the LHC injectors - the chain of accelerators preparing the beam for the LHC. One of the injectors - the second one in the chain - is the Proton Synchrotron (PS) Booster. Its performance is currently limited by the space-charge effect, which is the effect of the electromagnetic field of the particle beam on itself. This effect becomes weaker with higher energy, and therefore an energy upgrade of the PS Booster to 2 GeV maximum beam energy is foreseen. As the PS Booster is with its 40 years already an old machine, the construction of a new accelerator, a Rapid Cycling Synchrotron (RCS), to replace the PS Booster has been proposed. In this thesis different options for the beam guidance in the RCS - referred to as lattice and optics - are studied, followed by a more general comparison of different lattices and optics and their performance under consideration of the space-charge effect. To further complement the LHC physics program, also the possibility of deep inelastic lepton-nucleon scattering at the LHC has been suggested, referred to as Large Hadron Electron Collider (LHeC). In this case the proton beam of the LHC collides with the electron beam, which is accelerated in a separate newly built machine. Two options are considered as electron accelerator: a new energy recovery linac - the Linac-Ring option - and the installation of an electron ring in the existing LHC tunnel - the Ring-Ring option. One of the main challenges of the Ring-Ring option is the integration of the electron ring in the current LHC tunnel. A layout, lattice and optics of the electron accelerator is developed in this thesis, which meets the requirements with regard to integration and reaches the beam parameters demanded by the particle physics experiments.

  20. Simulations of electron-cloud heat load for the cold arcs of the CERN Large Hadron Collider and its high-luminosity upgrade scenarios

    CERN Document Server

    Maury Cuna, H; Zimmermann, F

    2012-01-01

    The heat load generated by an electron cloud in the cold arcs of the Large Hadron Collider (LHC) is a concern for operation near and beyond nominal beam current. We report the results of simulation studies, with updated secondary- emission models, which examine the severity of the electron heat load over a range of possible operation parameters, both for the nominal LHC and for various luminosity-upgrade scenarios, such as the so-called ‘‘full crab crossing’’ and ‘‘early separation’’ schemes, the ‘‘large Piwinski angle’’ scheme, and a variant of the latter providing ‘‘compatibility’’ with the (upgraded) LHCb experiment. The variable parameters considered are the maximum secondary-emission yield, the number of particles per bunch, and the spacing between bunches. In addition, the dependence of the heat load on the longitudinal bunch profile is investigated.

  1. Pope John Paul II visits CERN

    CERN Multimedia

    1982-01-01

    During Pope John Paul II's visit, Director-General Herwig Schopper presented him with a representation, made in the CERN workshops, of a high energy proton-antiproton interaction, such as was seen in the SPS collider.

  2. 2015 CERN-Fermilab HCP Summer School

    CERN Multimedia

    2015-01-01

    CERN and Fermilab are jointly offering a series of "Hadron Collider Physics Summer Schools", to prepare young researchers for these exciting times. The school has alternated between CERN and Fermilab, and will return to CERN for the tenth edition, from 24 June to 3 July 2015. The CERN-Fermilab Hadron Collider Physics Summer School is an advanced school targeted particularly at young postdocs and senior PhD students working towards the completion of their thesis project, in both Experimental High Energy Physics (HEP) and phenomenology. Lecture Topics include: Statistics in HEP, Heavy Flavour, Heavy Ion, Standard Model, Higgs searches and measurements, BSM theory, BSM searches, Top physics, QCD and Monte Carlos, Accelerators, Detectors for the future, Trigger and DAQ, Dark Matter Astroparticle, and two special lectures on Future Colliders, and 20 years after the top discovery. Calendar and Details: Mark your calendar for  24 June - 3 July 2015, when CERN will welcome students to t...

  3. Physics of W bosons at LEP

    CERN Document Server

    Mele, S

    2004-01-01

    The high-energy and high-luminosity data-taking campaigns of the LEP e+e- collider provided the four collaborations, ALEPH, DELPHI, L3 and OPAL, with about 50 000 W-boson pairs and about a thousand singly-produced W bosons. This unique data sample has an unprecedented reach in probing some aspects of the Standard Model of the electroweak interactions, and this article reviews several achievements in the understanding of W-boson physics at LEP. The measurements of the cross sections for W-boson production are discussed, together with their implication on the existence of the coupling between Z and W bosons. The precision measurements of the magnitude of triple gauge-boson couplings are presented. The observation of the longitudinal helicity component of the W-boson spin, related to the mechanism of electroweak symmetry breaking, is described together with the techniques used to probe the CP and CPT symmetries in the W-boson system. A discussion on the intricacies of the measurement of the mass of the W boson, ...

  4. Triangular flow of thermal photons from an event-by-event hydrodynamic model for 2.76 A TeV Pb + Pb collisions at the CERN Large Hadron Collider

    Science.gov (United States)

    Chatterjee, Rupa; Srivastava, Dinesh K.; Renk, Thorsten

    2016-07-01

    We calculate the triangular flow parameter v3 of thermal photons from an event-by-event ideal hydrodynamic model for 0-40% central collisions of Pb nuclei at √{sN N}=2.76 TeV at the CERN Large Hadron Collider. v3 determined with respect to the participant plane (PP) is found to be nonzero and positive, and its pT dependence is qualitatively similar to the elliptic flow parameter v2(PP) of thermal photons in the range 1 ≤pT≤6 GeV/c . In the range pT≤ 3 GeV/c , v3(PP) is found to be about 50-75% of v2(PP) and for pT> 3 GeV/c the two anisotropy parameters become comparable. The value of v3 is driven by local density fluctuations both directly via the creation of triangular geometry and indirectly via additional flow. As expected, the triangular flow parameter calculated with respect to the reaction plane v3(RP) is found to be close to zero. We show that v3(PP) strongly depends on the spatial size of fluctuations, especially in the higher pT(≥3 GeV /c ) region where a larger value of σ results in a smaller v3(PP ) . In addition, v3(PP ) is found to increase with the assumed formation time of the thermalized system.

  5. The LEP 2 machine : pushing to the limits 209 GeV! Exhibition LEPFest 2000

    CERN Multimedia

    2000-01-01

    By installing 288 new superconducting accelerating cavities after 1995,and thanks to the excellent work of the CERN teams,energies up to 209 GeV -well beyond LEP 's original design energy -have been achieved.Significant experi- mental data have been collected at energies in excess of 206 GeV.

  6. Facts about real antimatter collide with fiction

    CERN Multimedia

    Siegfried, Tom

    2004-01-01

    When science collides with fiction, sometimes a best seller emerges from the debris. Take Dan Brown's Angels & Demons, for instance, a murder mystery based on science at CERN, the European nuclear research laboratory outside Geneva

  7. Preparing for the Large Hadron Collider

    CERN Document Server

    Appleton, Owen

    2007-01-01

    "Processing data for the Large Hadron Collider, the next-generation particle accelerator under construction at CERN, Switzerland, is one of the driving forces for development of Grid technology." (1 page)

  8. CERN, accelerator of motivation

    CERN Multimedia

    François Becler

    2014-01-01

    Have your dreams ever come true? My dream did, when I was lucky enough to be allowed into the world’s largest particle physics laboratory and spend five whole days there.   François, in front of LEP's DELPHI detector, displayed in the LHCb cavern. François was given the opportunity to visit the experiment during his placement at CERN. I’m a pupil in my last year at the Collège Jean-Jacques Rousseau in Saint-Julien-en-Genevois and was on a work experience placement at CERN from 16 to 20 December last year. I’m so happy I was chosen because working alongside physicists and engineers of all nationalities was like a dream come true. The first thing that impressed me was the size of the site, its infrastructures and facilities but also the fact that I was working in a prestigious, world-renowned organisation. I spent lots of time looking at the map and trying to find my way around... CERN's such a massive place ! Th...

  9. Learning with the ATLAS Experiment at CERN

    Science.gov (United States)

    Barnett, R. M.; Johansson, K. E.; Kourkoumelis, C.; Long, L.; Pequenao, J.; Reimers, C.; Watkins, P.

    2012-01-01

    With the start of the LHC, the new particle collider at CERN, the ATLAS experiment is also providing high-energy particle collisions for educational purposes. Several education projects--education scenarios--have been developed and tested on students and teachers in several European countries within the Learning with ATLAS@CERN project. These…

  10. Observation of radiation degradation of electrical insulators in the CERN particle accelerators

    Science.gov (United States)

    Chevalier, Ch.; Coste, V.; Fontaine, A.; Tavlet, M.

    1999-05-01

    For the selection of polymer-based materials to be used in radiation environments, radiation tests have been performed at the European Organization for Particle Physics Research (CERN) for several decades. According to the recommendations of the IEC Standard 544, mechanical tests are carried out, and the radiation degradation is measured after accelerated irradiations. It is well known that during long-term exposures, oxygen and moisture are allowed to diffuse in the materials and hence to induce more severe degradation; this phenomenon is known as the `dose-rate effect'. During machine shut-downs, samples of rigid and flexible polymeric insulators (magnet-coil resins and cable insulations) have been taken out and tested after several years of exposure in the Super Proton Synchrotron (SPS) and in the Large Electron-Position Collider (LEP). The mechanical test results are compared to the ones after the accelerated qualification tests, and to the ones of a study conducted in 1991 to estimate the lifetime of cables in the radiation environment of LEP 200. They confirm that thermoplastics are more sensitive to long-term irradiations than the thermosetting resins and the composites, but that the dose-rate effect cannot be neglected in the latter.

  11. Rare B decays at LEP

    CERN Document Server

    Kluit, P M

    2001-01-01

    The results of the LEP experiments for rare B decays will be reviewed, covering hadronic final states, radiative and other rare decays and results for the inclusive charmless branching ratio. (8 refs).

  12. Le Japon contribue au grand collisionneur de hadrons du CERN

    CERN Multimedia

    CERN Press Office. Geneva

    1995-01-01

    Japan's Ministry of Education, Science and Culture (Monbusho), announced on May 10 that it would help to finance the construction of CERN*'s next particle accelerator, the Large Hadron Collider (LHC). This announcement follows the visit of a CERN delegation, led by Director-General Prof. Christopher Llewellyn Smith to Japan in March 1995.

  13. ISOLDE 1985-1987: In the shadow of LEP construction

    CERN Document Server

    CERN. Geneva

    2014-01-01

    This report describes my time at CERN from 1985 to 1987. Only very briefly before, ISOLDE was recognized by the CERN Management as a CERN facility and not only as a collaboration performing experiments at the synchrocyclotron (SC). Due to LEP construction the human resources were extremely restricted and I acted in one person as ISOLDE Group Leader, as Coordinator of the Synchrocyclotron, and as person responsible for the ISOLDE Technical Group. In addition, I was responsible for the students of my research groups from Mainz University which were active in laser spectroscopy of neutron-deficient nuclides in the mercury region and in getting ISOLTRAP on the floor and into operation. Due to LEP construction also the financial resources were extremely limited and my requests to the EP Division Leader B. Hyams and to the Director General H. Schopper for financial support for installation of a laser ion source and ISOLTRAP were turned down. Still, I and my students had a lot of fun at ISOLDE and I am very happy th...

  14. Towards Future Circular Colliders

    CERN Document Server

    AUTHOR|(CDS)2108454; Zimmermann, Frank

    2016-01-01

    The Large Hadron Collider (LHC) at CERN presently provides proton-proton collisions at a centre-of-mass (c.m.) energy of 13 TeV. The LHC design was started more than 30 years ago, and its physics programme will extend through the second half of the 2030’s. The global Future Circular Collider (FCC) study is now preparing for a post-LHC project. The FCC study focuses on the design of a 100-TeV hadron collider (FCC-hh) in a new ∼100 km tunnel. It also includes the design of a high-luminosity electron-positron collider (FCC-ee) as a potential intermediate step, and a lepton-hadron collider option (FCC-he). The scope of the FCC study comprises accelerators, technology, infrastructure, detectors, physics, concepts for worldwide data services, international governance models, and implementation scenarios. Among the FCC core technologies figure 16-T dipole magnets, based on $Nb_3Sn$ superconductor, for the FCC-hh hadron collider, and a highly efficient superconducting radiofrequency system for the FCC-ee lepton c...

  15. R-Parity Violation and CP-Violating and CP-Conserving Spin Asymmetries in scr(l)+scr(l)- → ν → τ+τ- : Probing Sneutrino Mixing at scr(l)+scr(l)- Colliders

    International Nuclear Information System (INIS)

    We consider the sneutrino resonance reaction ell +ell -→ν →τ+τ- in the minimal supersymmetric standard model (MSSM) without R parity. We introduce CP-violating and CP-conserving τ-spin asymmetries which are generated at tree level if there is ν-anti ν mixing and are forbidden in the standard model. At the CERN e+e- collider LEP2, these asymmetries may reach ∼75% around resonance for sneutrino mass splitting of Δm∼Γνμ and ∼10% for splitting as low as Δm∼0.1Γνμ . They may be easily detectable if the beam energy is within ∼10 GeV around the νμ mass and may therefore serve as powerful probes of sneutrino mixing. Future colliders are also discussed. copyright 1998 The American Physical Society

  16. 1988 CERN school of physics

    International Nuclear Information System (INIS)

    The CERN School of Physics is intended to give young experimental physicists an introduction to the theoretical aspects of recent advances in elementary particle physics. These Proceedings contain reports of lecture series on the following topics: introduction to field theory and to weak interactions, heavy ion collisions, perturbative QCD, the standard model, proton-antiproton collider results and detectors, cosmology. (orig.)

  17. Cern collisions light up Copenhagen

    CERN Multimedia

    Banks, Michael

    2010-01-01

    "Anyone passing by the Niels Bohr Institute in Copenhagen, Denmark, might be startled by some strange moving lights on the facade of the institute's main building. In fact, the dancing beams show, almost in real time, collisions form the Atlas experiment at Cern's Large Hadron Collider (LHC)" (1 paragraph)

  18. ECFA workshop on LEP 200. Vol. 1 and 2

    International Nuclear Information System (INIS)

    On the initiative of the European Committee for Future Accelerators, a workshop was organized to study experimental and theoretical aspects of the physics feasible at LEP with the beam energy increased to its design value of 100 GeV per beam. These two volumes provide the written versions of the reports presented by nine working groups to the workshop, as well as the presentations on the machine upgrade itself and the potential of hadron colliders and of HERA for LEP 200 physics. Each working group studied a specific topic, evaluating in some detail the requirements both for the detectors and for the machine of W mass measurements, W decay properties, W production dynamics, electroweak radiative corrections, two-photon physics, new heavy quarks and leptons, Higgs particles, supersymmetric particles, and composite models. The proceedings also include some of the more detailed work done in the framework of the working groups. (orig.)

  19. Cryogénie et supraconductivité pour le grand collisionneur de hadrons (LHC) du CERN

    CERN Document Server

    Lebrun, P

    2004-01-01

    The Large Hadron Collider (LHC), presently in construction at CERN, the European Organization for Nuclear Research near Geneva (Switzerland), will be the most advanced research instrument of the world’s high-energy physics community, providing access to the structure of matter at an unprecedentedly fine scale. Reusing the 26.7 km circumference tunnel and infrastructure of the past LEP electron-positron collider, the LHC makes use of advanced technology: high-field superconducting magnets based on niobium-titanium alloy conductors operating in superfluid helium at 1.9 K will guide and bring into collision intense beams of protons and ions. After some ten years of focussed R&D, the LHC components are being series-built by specialized industry in CERN member states and procured through world-wide collaborations. After briefly recalling the physics goals, performance challenges and design choices, we present main aspects of cryogenics and superconductivity as key technologies for the LHC and report on its c...

  20. QCD results from LEP1 and 2

    CERN Document Server

    Kluth, S

    1998-01-01

    Recent results from QCD analyses at LEP1 and LEP2 are presented. High statistics LEP1 analyses make use of the very large data samples recorded at square root s approximately=M/sub Z/0 and provide detailed tests of perturbative QCD, QCD based Monte Carlo models and also of the differences between quark and gluon jets. The LEP2 analyses are based on very small data sets at high energy and provide general tests of QCD. Combined data on measurements of the strong coupling alpha /sub s/ from LEP1 and LEP2 give good evidence that in QCD a running coupling is preferred over a constant coupling. (57 refs).

  1. Transporting the last superconducting module to be removed from LEP

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    All 72 of LEP's superconducting modules have now been raised to the surface. Some 80% will be preserved at CERN, with 10% being reused for the LHC and a further 10% of obsolete non-radioactive material destined for recycling. These pictures show the last of these modules on its journey from PM18 to the old ISR tunnel where the modules will be stored in the short term. Photo 01: The Ansaldo 1020 module leaves PM18 by lorry. Photo 03: The module on the SM18 site. Photos 06, 08: The module on the road.

  2. Design flaw could delay collider

    CERN Multimedia

    Cho, Adrian

    2007-01-01

    "A magnet for the Large Hadron Collider (LHC) failed during a key test at the European particle physics laboratory CERN last week. Physicists and engineers will have to repair the damaged magnet and retrofit others to correct the underlynig design flaw, which could delay the start-up of the mammouth subterranean machine." (1,5 page)

  3. Collider physics: A theorist's view

    International Nuclear Information System (INIS)

    Recent experimental results from the CERN anti p p Collider are reviewed from a theorist's perspective. The conclusion is that the standard model is impressively verified and nothing else seems to be present. Some other relevant phenomenological and theoretical issues are also reviewed

  4. Design flaw could delay collider

    CERN Multimedia

    Cho, Adrian

    2007-01-01

    "A magnet for the Large Hadron Collider (LHC) failed during a key test at the European particle physics laboratory CERN last week. Physicists and engineers will have to repair the damaged manget and retrofil others to correct the underlying design flaw.."(1 page)

  5. The Spirit counts - People at and around CERN

    CERN Document Server

    CERN. Geneva

    2014-01-01

    After a few biographical remarks I shall concentrate on human aspects which are not covered by official documents, but which are as important to the success of CERN as scientific and technical competence. The approval of LEP, general problems of the project management and the approval of the LEP experiments under conditions never encountered before at CERN will be covered. The special spirit created at CERN based on the competence and solidarity of the CERN staff and its users made it possible to find new ways of successful international collaboration combining competition with cooperation. Career Summary Physics diploma and doctorate from Hamburg University, now Prof. emer.; research assistant at Stockholm Technical University (with Lise Meitner); Cavendish Laboratory UK (with O.R.Frisch); Cornell University (with R.R. Wilson); research in optics, nuclear and elementary particle physics. various professorships in Germany and director of university institutes; Director of DESY, Hamburg, 1973-1980...

  6. Physics studies at a future linear collider

    OpenAIRE

    Tabassam, Hajrah

    2012-01-01

    With the start of the Large Hadron Collider(LHC) at CERN, we will obtain a new understanding of the physics beyond our current limits. New discoveries will be made; but we will require a deeper understanding, which the LHC machine, being a hadron collider, will not be able to elucidate. Instead, we will need an e+e- collider to make precision measurements of the newly discovered phenomena. Electroweak symmetry breaking and the origin of fermion and boson masses are fundament...

  7. Una evaluación externa del CERN aconseja mejorar la gestión

    CERN Document Server

    2002-01-01

    An external committee of evaluation which studied the CERN situation before it undertook the construction of the Large Hadron Collider said the design of this new machine is excellent, but that CERN should improve its management

  8. CERN Choir

    CERN Multimedia

    Staff Association

    2015-01-01

      Do you like singing? The CERN Choir is looking for basses and tenors Join us! Programme Spring Session 2015: Donizetti: Misere & Missa di Gloria e Credo Bellini: Salve Regina Bruckner: Requiem in D minor Next concert: Sunday 31 May 2015 at 17:00 Musicales de Comesières (GE) Rehearsals at CERN Main Auditorium, building 500 On Wednesdays from 20.00 to 22:00 Membership fee: January to June 150 CHF September to December: 100CHF Contact: Baudouin.bleus@cern.ch Facebook/Choeur-du-CERN

  9. WORK ON TELEPHONE NETWORK LEP SITE

    CERN Multimedia

    2000-01-01

    The telephone service will make modifications on the LEP network the 12th December 2000 from 5.30pm. This will cause disturbances on telephone connections on the whole LEP area. For more information please call 160026.

  10. Radiative corrections for the LHC and linear collider era

    NARCIS (Netherlands)

    E. Laenen; D. Wackeroth

    2009-01-01

    We emphasize the importance of including radiative corrections when extracting physics from colliders such as the Tevatron Run II at Fermilab, the Large Hadron Collider (LHC) at CERN, and a future linear collider (LC). We review both well-tested methods and recent advances for calculating these corr

  11. Le LEP sera encore là en l'an 2000

    CERN Multimedia

    CERN Press Office. Geneva

    1998-01-01

    CERN's Large Electron-Positron collider got the green light today to achieve its full potential by running for an additional year in the year 2000. Delegates attending the 110th meeting of the Laboratory's governing body, Council, approved the move after a careful presentation of the proposal's scientific merits and financial aspects by CERN's Director General Chris Llewellyn Smith.

  12. CERN is 25 years old

    CERN Document Server

    Anthoine, R

    1979-01-01

    Reviews the history of CERN, the European Organisation for Nuclear Research, which has just celebrated its twenty-fifth anniversary. The member states, the site (Geneva) and accelerators, and the research carried out are all discussed. Amongst the apparatus and research described are the SPS (Super Proton Synchrotron), the ISOLDE linear isotope separator, BEBC (Big European Bubble Chamber), and the ISR (Intersecting Storage Rings). Discoveries made since the founding of CERN include that of neutral currents, measurement of the magnetic characteristics of the muon to a great accuracy, creation of exotic atoms, neutrino analysis of proton and neutron structure, hadron classification, future/past time asymmetry in neutral kaons, and the first measurements of the lifetimes of charmed hadrons. Future projects considered include LEP, the Large Electron Positron Ring. (0 refs).

  13. CASE in CERN's accelerator sector

    International Nuclear Information System (INIS)

    As in the software industry where computer aided software engineering (CASE) methodologies and tools are commonly used, CERN endeavours to introduce this technology to improve the efficiency of designing, producing and maintaining software. A large project is currently under development in the administrative area whereas a dedicated group had been set up to evaluate state of the art techniques for software development relating to physics experiments. A similar activity, though on a smaller scale, has been initiated in the accelerator sector also in view of the large amount of software that will be required by the LEP200 and the LHC projects. This paper briefly describes this technology and gives an account of current experience with the use of CASE methods and tools for technical projects in the accelerator sector at CERN. (author)

  14. CERN honours Carlo Rubbia

    CERN Multimedia

    2009-01-01

    On 7 April CERN will be holding a symposium to mark the 75th birthday of Carlo Rubbia, who shared the 1984 Nobel Prize for Physics with Simon van der Meer for contributions to the discovery of the W and Z bosons, carriers of the weak interaction. Following a presentation by Rolf Heuer, lectures will be given by eminent speakers on areas of science to which Carlo Rubbia has made decisive contributions. Michel Spiro, Director of the French National Institute of Nuclear and Particle Physics (IN2P3) of the CNRS, Lyn Evans, sLHC Project Leader, and Alan Astbury of the TRIUMF Laboratory will talk about the physics of the weak interaction and the discovery of the W and Z bosons. Former CERN Director-General Herwig Schopper will lecture on CERN’s accelerators from LEP to the LHC. Giovanni Bignami, former President of the Italian Space Agency and Professor at the IUSS School for Advanced Studies in Pavia will speak about his work with Carlo Rubbia. Finally, Hans Joachim Sch...

  15. CERN honours Carlo Rubbia

    CERN Multimedia

    2009-01-01

    On 7 April CERN will be holding a symposium to mark the 75th birthday of Carlo Rubbia, who shared the 1984 Nobel Prize for Physics with Simon van der Meer for contributions to the discovery of the W and Z bosons, carriers of the weak interaction. Following a presentation by Rolf Heuer, lectures will be given by eminent speakers on areas of science to which Carlo Rubbia has made decisive contributions. Michel Spiro, Director of the French National Institute of Nuclear and Particle Physics (IN2P3) of the CNRS, Lyn Evans, sLHC Project Leader, and Alan Astbury of the TRIUMF Laboratory will talk about the physics of the weak interaction and the discovery of the W and Z bosons. Former CERN Director-General Herwig Schopper will lecture on CERN’s accelerators from LEP to the LHC. Giovanni Bignami, former President of the Italian Space Agency, will speak about his work with Carlo Rubbia. Finally, Hans Joachim Schellnhuber of the Potsdam Institute for Climate Research and Sven Kul...

  16. Courrier CERN

    CERN Multimedia

    2015-01-01

    Example of the cover page of the French version of the CERN Courier; Courrier CERN from January 1962. The journal was published both in English and French up to volume 45, no. 5, June 2005. Since then there is a single-language edition where articles are published either in French or English with an abstract in the other language.

  17. CERN & Society

    CERN Multimedia

    2016-01-01

    Non Member State Summer Students 2015 are interviewed about their decision to study STEM subjects, to apply for CERN NMSSS programme, their experience onsite @CERN and takeaways, their future goals and aspirations, offering also advice to fellow students.The Non Member State Summer Student Programme stands for a unique opportunity for students from all over the world to spend their summer at CERN in Geneva, getting involved in some of the world’s biggest experiments. For 8 weeks, summer students gather on-site at CERN and join in the day-to-day work of research. The Programme targets advanced undergraduate and beginning graduate students of physics, computing and engineering, particularly from developing countries. Participating students receive scientific training, attend lectures and work on laboratory-based projects alongside with CERN experts and fellow students.

  18. Neutral Higgs bosons in the standard model and in the minimal supersymmetric model: Searches at LEP

    Indian Academy of Sciences (India)

    P Igo-Kemenes

    2004-03-01

    During the twelve years of operation of the $e^{+}e^{-}$ collider LEP, the associated collaborations, ALEPH, DELPHI, L3 and OPAL, have extensively searched for Higgs bosons over a broad range of masses. We present the final results from LEP for the standard model Higgs boson which are obtained from a statistical combination of the data from the four experiments. We also present preliminary combined results for neutral Higgs bosons in the minimal supersymmetric model (MSSM) where the Higgs sector is assumed to be CP invariant. Finally, we discuss an alternative MSSM scenario including CP violation in the Higgs sector.

  19. Future frontiers for e/sup +/e/sup -/ collisions: physics of SLC and LEP

    Energy Technology Data Exchange (ETDEWEB)

    Dorfan, J.M.

    1986-04-01

    A brief historical review is given of the contribution to particle physics of e/sup +/e/sup -/ interactions, followed by a discussion of the LEP and SLC machines and the reasons for developing linear colliders. A brief overview of the Standard Model and some essential formalism for the process e/sup +/e/sup -/ ..-->.. f anti f are presented, followed by a discussion of detectors. Tests of the Standard Model and physics beyond the Standard Model that can be made running at the Z/sup 0/ are considered. LEP physics at energies above the Z/sup 0/ is discussed. (LEW)

  20. Carlo Rubbia, former CERN Director-General, appointed Senator for life by the President of Italy.

    CERN Multimedia

    Antonella Del Rosso

    2013-01-01

    Today, the President of the Italian Republic Giorgio Napolitano appointed four new senators for life: the music director and conductor “maestro” Claudio Abbado, the neuroscientist Professor Elena Cattaneo, the renowned architect Renzo Piano and Professor Carlo Rubbia, who was CERN Director-General from 1989 to 1993.   Carlo Rubbia during his talk for the discovery of the W particle in 1983. In 1984, Carlo Rubbia, then head of the UA1 collaboration, was awarded the Nobel Prize in Physics, together with Simon van der Meer, for the discovery of the W and Z particles – at that time two important missing components of the Standard Model. During his term of office as Director-General, the Large Electron Positron collider was inaugurated and the four LEP experiments produced their first results. He also mounted the case for the new Large Hadron Collider, which in 2012 led to the discovery of a Higgs boson. In 1993, the last year of his mandate, the World Wide Web proto...

  1. Heavy quark physics from LEP

    Energy Technology Data Exchange (ETDEWEB)

    Dornan, P.J. [Imperial College of Science Technology and Medicine, London (United Kingdom)

    1997-01-01

    A review of some of the latest results on heavy flavor physics from the LEP Collaborations is presented. The emphasis is on B physics, particularly new results and those where discrepancies is given of the many techniques which have been developed to permit these analyses.

  2. Tests of QCD at lep

    International Nuclear Information System (INIS)

    In this report, some aspects of the reaction Z0 -> qq-bar are presented and compared to the predictions of perturbative QCD. Recent results from LEP 1990 data are shown, concerning measurements of αs with global event shape variables, of gluon properties through 3-jet event orientations and comparison of gluon and quark fragmentation. (author)

  3. Heavy quark physics from LEP

    International Nuclear Information System (INIS)

    A review of some of the latest results on heavy flavor physics from the LEP Collaborations is presented. The emphasis is on B physics, particularly new results and those where discrepancies is given of the many techniques which have been developed to permit these analyses

  4. Colour reconnection at LEP2

    CERN Document Server

    Abreu, P

    2002-01-01

    The preliminary results on the search of colour reconnection effects (CR) from the four experiments at LEP, ALEPH, DELPHI, L3 and OPAL, are reviewed. Extreme models are excluded by studies of standard variables, and on going studies of a method first suggested by L3, the particle flow method (D. Duchesneau, (2001)), are yet inconclusive. (22 refs).

  5. CERN Rocks

    CERN Multimedia

    2004-01-01

    The 15th CERN Hardronic Festival took place on 17 July on the terrace of Rest 3 (Prévessin). Over 1000 people, from CERN and other International Organizations, came to enjoy the warm summer night, and to watch the best of the World's High Energy music. Jazz, rock, pop, country, metal, blues, funk and punk blasted out from 9 bands from the CERN Musiclub and Jazz club, alternating on two stages in a non-stop show.  The night reached its hottest point when The Canettes Blues Band got everybody dancing to sixties R&B tunes (pictured). Meanwhile, the bars and food vans were working at full capacity, under the expert management of the CERN Softball club, who were at the same time running a Softball tournament in the adjacent "Higgs Field". The Hardronic Festival is the main yearly CERN music event, and it is organized with the support of the Staff Association and the CERN Administration.

  6. Muon colliders

    International Nuclear Information System (INIS)

    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should thus be regarded as complementary. Parameters are given of 4 TeV and 0.5 TeV high luminosity micro+micro-colliders, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders, starting from the proton accelerator needed to generate the muons and proceeding through muon cooling, acceleration and storage in a collider ring. Problems of detector background are also discussed

  7. Muon colliders

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, R.B. [Brookhaven National Lab., Upton, NY (United States)]|[Stanford Linear Accelerator Center, Menlo Park, CA (United States); Sessler, A. [Lawrence Berkeley Lab., CA (United States); Skrinsky, A. [BINP, RU-630090 Novosibirsk (Russian Federation)] [and others

    1996-01-01

    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should thus be regarded as complementary. Parameters are given of 4 TeV and 0.5 TeV high luminosity {micro}{sup +}{micro}{sup {minus}}colliders, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders, starting from the proton accelerator needed to generate the muons and proceeding through muon cooling, acceleration and storage in a collider ring. Problems of detector background are also discussed.

  8. Collider physics for the late 1980's

    International Nuclear Information System (INIS)

    Topics in the Standard Model of strong and electroweak interactions and how these topics are relevant for the high energy colliders are discussed. Radiative corrections in the Glashow-Weinberg-Salam model are discussed, stressing how these corrections may be measured at LEP and the SLC. CP violation is discussed, followed by a discussion of the Higgs boson and the searches which can be carried out for it. Some features of quantum chromodynamics are discussed which are relevant to hadron colliders. Some of the problems which the Standard Model does not solve are discussed. 115 refs., 53 figs

  9. Automatic high voltage conditioning of the electrostatic LEP separators without conventional programming

    CERN Document Server

    Balhan, B; Carlier, E; Dieperink, J H; Mertens, V

    1995-01-01

    The TS Tool Kit is a generic, fully data-driven, and user-configurable software system developed at CERN for supervisory, control, and data acquisition applications. It provides a comprehensive framework to solve fairly complex process control problems requiring response times of the order of a second, without any need for conventional programming. The characteristics and benefits of this approach are discussed at the example of the new high voltage conditioning process for the electrostatic LEP separators.

  10. Heavy meson production at a low-energy photon collider

    CERN Document Server

    Asztalos, S

    2004-01-01

    A low-energy $\\gamma\\gamma$ collider has been discussed in the context of a testbed for a $\\gamma\\gamma$ interaction region at the Next Linear Collider (NLC). We consider the production of heavy mesons at such a testbed using Compton-backscattered photons and demonstrate that their production rivals or exceeds those by BELLE, BABAR or LEP where they are produced indirectly via virtual $\\gamma\\gamma$ luminosities.

  11. Denis Guedj at CERN

    CERN Multimedia

    2009-01-01

    Denis Guedj (right), pictured with Etiennette Auffray Hillemanns of the CMS collaboration and Hartmut Hillemanns of the DG-KTT group.French author Denis Guedj, who is also a mathematician and Professor of History of Science at Paris VIII University, visited CERN on 7 and 8 October. During a presentation in the CERN Library he discussed his 15 published books and likened the process of novel writing to working on a scientific experiment: it begins with a limited amount of data, and then questions arise, problems are solved and further research reveals truths. Denis Guedj works hard to ensure that his novels contain ‘true fiction’. His most recent visit to CERN will help him to write a new book set at the LHC in which he will combine his scientific interest in what happens when a proton and proton collide with a human story about what happens to a male and female physicist who meet in the LHC tunnel. "Visiting the CMS cavern was...

  12. Signatures of the anomalous $Z\\gamma$ and $ZZ$ production at the lepton and hadron Colliders

    CERN Document Server

    Gounaris, George J; Renard, F M

    2000-01-01

    The possible form of the ZZZ, ZZ$\\gamma$ and $Z\\gamma \\gamma$ vertices which may be induced from some New Physics interactions is critically examined. Their signatures and the possibilities to study them, through ZZ and $Z\\gamma$ production, at the e^-e^+ Colliders LEP and LC and at the hadronic Colliders Tevatron and LHC, are investigated.

  13. Theory status of four-fermion production at e-e+ colliders

    CERN Document Server

    Schwinn, Christian

    2015-01-01

    The status of predictions for four-fermion production at e-e+ colliders is reviewed with an emphasis on the developments after the LEP2 era and an outlook to the challenges posed by the precision program at future colliders.

  14. CERN boss quashes LHC delay rumours

    CERN Multimedia

    2007-01-01

    "Robert Aymar, the director general of CERN, has dispelled rumours that a series of buckled electrical connectors at the Large Hadron Collider will delay the accelerator's official start-up date of May 2008. Writing in this week's CERN Bulletin, Aymar says that the problem concerns only a small percentage of the connectors and that it is "business as usual" for bringing the new accelerator online." (1,5 page)

  15. Le Japon devient observateur au CERN

    CERN Multimedia

    CERN Press Office. Geneva

    1995-01-01

    A Japanese delegation, lead by Mr. Kaoru Yosano, Japan's Minister of Monbusho, (Ministry of Education, Science and Culture), was warmly applauded by the delegates of CERN's Member States when it entered the Council Chamber for the first time as an official Observer. Mr. Yosano, thanked the CERN Council for unanimously agreeing to grant Japan Official Observer Status and also accepting Japan's offer to contribute to the Large Hadron Collider (LHC) project.

  16. University of Tennessee deploys force10 switch for CERN work

    CERN Multimedia

    2007-01-01

    "Force20 networks, the pioneer in building and securing reliable networks, today announced that the University of Tennessee physics department has deployed the C300 resilient switch to analyze data form CERN's Large Hadron Collider." (1/2 page)

  17. Researchers visit CERN in search of elusive Higgs boson

    CERN Multimedia

    2007-01-01

    "When Switzerland's CERN laboratory newest particle collider begins smashing atoms, scientists from the University of Chicago and Indiana University will be there to help crunch the data by using a worldwide supercomuting grid." (1 page)

  18. CERN confirms goal of 2007 start-up for LHC

    CERN Multimedia

    2005-01-01

    Speaking at the 131st session of CERN Council on 17 December 2004, the Director-General, Robert Aymar, confirmed that the top priority is to maintain the goal of starting up the Large Hadron Collider (LHC) in 2007.

  19. Llewellyn Smith, Director-General designate of CERN, discusses LHC

    CERN Multimedia

    Sweet, William N

    1992-01-01

    Christopher Llewellyn Smith was nominated by the Committee of Council to be Director General of CERN. He aims to pave the way for the Large Hadron Collider and utilize to the full the Large Electron-Positron machine.

  20. LEPS backward gamma detector reassembled

    International Nuclear Information System (INIS)

    A new electro-magnetic (EM) calorimeter complex FOREST covering a solid angle of about 4π sr is under construction. It consists of three calorimeters: the EPS forward one made up of pure CsI crystals, the middle one of lead scintillating fiber (Lead/SciFi) modules, and the backward one of lead glass Cerenkov counters. We have reassembled the middle calorimeter, comprised of 252 Lead/SciFi modules, which used to be the LEPS Backward Gamma detector system utilized in a LEPS experiment at SPring-8. A performance test for the gamma detector system has been made with a photon beam in the GeV γ experimental hall. The π0 peak is clearly observed in the γγ invariant mass distribution. (author)

  1. LEP vacuum chamber, early prototype

    CERN Multimedia

    1978-01-01

    The structure of LEP, with long bending magnets and little access to the vacuum chamber between them, required distributed pumping. This is an early prototype for the LEP vacuum chamber, made from extruded aluminium. The main opening is for the beam. The small channel to the right is for cooling water, to carry away the heat deposited by the synchroton radiation from the beam. The 4 slots in the channel to the left house the strip-shaped ion-getter pumps (see 7810255). The ion-getter pumps depended on the magnetic field of the bending magnets, too low at injection energy for the pumps to function well. Also, a different design was required outside the bending magnets. This design was therefore abandoned, in favour of a thermal getter pump (see 8301153 and 8305170).

  2. Niobium LEP 2 accelerating cavities

    CERN Multimedia

    An accelerating cavity from LEP. This could be cut open to show the layer of niobium on the inside. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment. These challenging requirements pushed European industry to new achievements. 256 of these cavities were used in an upgrade of the LEP accelerator to double the energy of the particle beams.

  3. CERN and the high energy frontier

    Directory of Open Access Journals (Sweden)

    Tsesmelis Emmanuel

    2014-04-01

    Full Text Available This paper presents the particle physics programme at CERN at the high-energy frontier. Starting from the key open questions in particle physics and the large-scale science facilities existing at CERN, concentrating on the Large Hadron Collider(LHC, this paper goes on to present future possibilities for global projects in high energy physics. The paper presents options for future colliders, all being within the framework of the recently updated European Strategy for Particle Physics, and all of which have a unique value to add to experimental particle physics. The paper concludes by outlining key messages for the way forward for high-energy physics research.

  4. Big research in new dimensions. Thinkers of our time about the actual elementary-particle physics at CERN; Grossforschung in neuen Dimensionen. Denker unserer Zeit ueber die aktuelle Elementarteilchenphysik am CERN

    Energy Technology Data Exchange (ETDEWEB)

    Kommer, Christoph (ed.) [Heidelberg Univ. (Germany); DKFZ, Heidelberg (Germany); Satz, Helmut [Bielefeld Univ. (Germany). Fakultaet fuer Physik; Blanchard, Philippe [Bielefeld Univ. (Germany). Abt. Theoretische Physik

    2016-07-01

    The following topics are dealt with: Research from the highest energies to the smallest particles at CERN, the laborious way to the Large Hadronic Collider, CERN as accelerator of techniques, culture, and society, a philosophical and sociological perspective of questions concerning CERN, quark matter research at CERN, the FAIR facility for antiproton and ion research. (HSI)

  5. Physics beyond Colliders Kickoff Workshop

    CERN Document Server

    2016-01-01

    The aim of the workshop is to explore the opportunities offered by the CERN accelerator complex and infrastructure to get new insights into some of today's outstanding questions in particle physics through projects complementary to high-energy colliders and other initiatives in the world. The focus is on fundamental physics questions that are similar in spirit to those addressed by high-energy colliders, but that may require different types of experiments. The kickoff workshop is intended to stimulate new ideas for such projects, for which we encourage the submission of abstracts.

  6. Workshop on Physics Beyond Colliders

    CERN Document Server

    2016-01-01

    The aim of the workshop is to explore the opportunities offered by the CERN accelerator complex and infrastructure to get new insights into some of today's outstanding questions in particle physics through projects complementary to high-energy colliders and other initiatives in the world. The focus is on fundamental physics questions that are similar in spirit to those addressed by high-energy colliders, but that may require different types of experiments. The kick-off workshop is intended to stimulate new ideas for such projects, for which we encourage the submission of abstracts.

  7. Big research in new dimensions. Thinkers of our time about the actual elementary-particle physics at CERN

    International Nuclear Information System (INIS)

    The following topics are dealt with: Research from the highest energies to the smallest particles at CERN, the laborious way to the Large Hadronic Collider, CERN as accelerator of techniques, culture, and society, a philosophical and sociological perspective of questions concerning CERN, quark matter research at CERN, the FAIR facility for antiproton and ion research. (HSI)

  8. Signals of universal extra dimension at the international linear collider

    Indian Academy of Sciences (India)

    Biplob Bhattacherjee

    2007-11-01

    In the minimal universal extra dimension model, single production of = 2 gauge bosons provides a unique discriminating feature from supersymmetry. We discuss how the proposed international linear collider can act as a = 2 factory, much in the same vein as LEP.

  9. R{sub c} measurements at LEP

    Energy Technology Data Exchange (ETDEWEB)

    Baudot, J. [European Organization for Nuclear Research, Geneva (Switzerland); LEP Collaboration

    1996-08-01

    The partial width R{sub c} is a basic observable in Z physics. Within the Standard Model its value is accurately predicted and other experimental measurements at LEP involve its knowledge. The DELPHI and OPAL collaborations have presented several R{sub c} measurements. All methods are based on charmed hadron reconstruction and b/c separation. The LEP average, computed by the LEP Electroweak Heavy Flavor Working Group, is presented. (author). 11 refs.

  10. The Heavy Baryon Physics by means LEP

    International Nuclear Information System (INIS)

    This report describes the experimental research about the heavy baryons which were obtained in the last decade at LEP. The most important among them concern the lifetimes of beauty baryons. The methods of theoretical description of heavy hadrons together with the LEP experimental apparatus are also discussed. Heavy baryon studies are shown in a broader perspective of other LEP results: the test of the standard model and the latest measurements concerning the beauty mesons. (author)

  11. Large Hadron Collider slideshow shows future of physics

    CERN Multimedia

    Kramer, S E

    2007-01-01

    "The European organization for Nuclear Research (CERN) has been building the Large Hadron Collider for many years, but it's finally taking shape and prepping to operate at full power in 2008." (1/2 page)

  12. CERN celebrates discoveries and looks to the future

    CERN Document Server

    CERN Press Office. Geneva

    2003-01-01

    Nobel laureates will be among the distinguished guests at a symposium at CERN on 16 September. The symposium will celebrate the double anniversary of major discoveries at CERN that underlie the modern theory of particles and forces. It will also look forward to future challenges and opportunities ... with the construction of the Large Hadron Collider.

  13. Destination Universe: The Incredible Journey of a Proton in the Large Hadron Collider

    CERN Multimedia

    Lefevre, C

    2008-01-01

    This brochure illustrates the incredible journey of a proton as he winds his way through the CERN accelerator chain and ends up inside the Large Hadron Collider (LHC). The LHC is CERN's flagship particle accelerator which can collide protons together at close to the speed of light, creating circumstances like those just seconds after the Big Bang.

  14. Destination Universe: The Incredible Journey of a Proton in the Large Hadron Collider (English version)

    CERN Multimedia

    Lefevre, C

    2008-01-01

    This brochure illustrates the incredible journey of a proton as he winds his way through the CERN accelerator chain and ends up inside the Large Hadron Collider (LHC). The LHC is CERN's flagship particle accelerator which can collide protons together at close to the speed of light, creating circumstances like those just seconds after the Big Bang.

  15. Signing of the agreement between CERN and the United States

    CERN Multimedia

    1997-01-01

    Siging of the agreement between CERN and the United States for a contribution of $531 million to the Large Hadron Collider (LHC) project. The Agreement was signed by Dr. Matha Krebs, Director of the Office of Energy Research, DOE, Dr Bob Eisenstein, Assistant Director of Physical and Mathematical Science, NSF, and Prof. Christopher Llewellyn Smith, Director General of CERN at the Council session in December 1997. At the same occasion, the USA was granted Observer Status at CERN.

  16. Robot adventures at CERN

    CERN Multimedia

    2015-01-01

    Imagine if the CERN robots had an end-of-year party... From retrieving data tapes to handling material safely, the robots at CERN fulfill numerous tasks. Find out more: http://cern.ch/go/VjX7 Produced by: CERN Video Productions Director: Christoph M. Madsen Copyright © 2015 CERN. Terms of use: http://copyright.web.cern.ch/

  17. CERN choir

    CERN Document Server

    2004-01-01

    Don't forget a special performance of Joseph Haydn's Creation, an oratorio in three parts, given by the CERN choir and the Annecy choir Pro Musica, this Sunday at 8.30 p.m. at the Grand Casino. Tickets (38 CHF) are available at Fnac Rive and Balexert.

  18. Vacuum Chambers for LEP sections

    CERN Multimedia

    1983-01-01

    The picture shows sections of the LEP vacuum chambers to be installed in the dipole magnets (left) and in the quadrupoles (right). The dipole chamber has three channels: the beam chamber, the pumping duct where the NEG (non-evaporabe getter) is installed and the water channel for cooling (on top in the picture). The pumping duct is connected to the beam chamber through holes in the separating wall. The thick lead lining to shield radiation can also be seen. These chambers were manufactured as extruded aluminium alloy profiles.

  19. Test Accommodations for LEP Students. ERIC Digest.

    Science.gov (United States)

    Stansfield, Charles; Rivera, Charlene

    This digest presents an overview of accommodations for students of limited English proficiency (LEP) and an overview of inclusion practices on statewide assessments, with emphasis on the accommodation known as linguistic simplification. The inclusion of LEP students in statewide testing programs over the last decade has been uneven. In the…

  20. LEP des inquiétudes subsistent

    CERN Multimedia

    1984-01-01

    Certains propriétaires de terrains et de constructions situés sur le pourtour du LEP restent inquiets: qu'arriverait-il an cas de contestation sur la valeur de réparation d'éventuels dommages causés par la construction du LEP? (1 page).

  1. The collider of the future?

    CERN Document Server

    CERN Audiovisual Service

    2009-01-01

    Why are two studies for one linear collider being conducted in parallel? This is far from a duplication of effort or a waste of resources, since the two studies reflect a complementary strategy aimed at providing the best technology for future physics. On Friday 12 June CERN hosted the first joint meeting between CLIC and ILC, which led to a host of good results and important decisions. The International Linear Collider (ILC) and Compact Linear Collider (CLIC) studies both call for cutting-edge technologies. At first glance they may appear to be in competition, but they are in fact complementary and have a common objective – namely to propose a design , as soon as possible and at the lowest possible cost, for the linear accelerator best suited to taking over the baton of physics research at the high-energy frontier after the LHC.

  2. The muon spectrometer of the L3 detector at LEP

    International Nuclear Information System (INIS)

    In this thesis the construction of the muon spectrometer of the L3 detector is described, one of the four detectors presently being prepared for experimentation at LEP. This accelerator is built at CERN, Geneva, and is due to start operation in July 1989. One of the unique features of the L3 experiment is the measurement of the momentum of the muons produced in the e+e- collisions iwht an independent muon spectrometer. This makes it possible to study final states involving muons, with high accuracy (δP/P = 2% at 45 GeV). The muon spectrometer consists of 80 large drift chambers, arranged in 16 modules or 'octants', that fill a cylindrical volume of 12 m in length, 5 m inner diameter and 12 m outer diameter. The design of the drift chambers, the construction, the alignment procedure and the test results for the complete octants are described. 51 refs.; 57 figs.; 16 tabs

  3. 1984 CERN school of computing

    International Nuclear Information System (INIS)

    The eighth CERN School of Computing covered subjects mainly related to computing for elementary-particle physics. These proceedings contain written versions of most of the lectures delivered at the School. Notes on the following topics are included: trigger and data-acquisition plans for the LEP experiments; unfolding methods in high-energy physics experiments; Monte Carlo techniques; relational data bases; data networks and open systems; the Newcastle connection; portable operating systems; expert systems; microprocessors - from basic chips to complete systems; algorithms for parallel computers; trends in supercomputers and computational physics; supercomputing and related national projects in Japan; application of VLSI in high-energy physics, and single-user systems. See hints under the relevant topics. (orig./HSI)

  4. 1987 CERN school of computing

    International Nuclear Information System (INIS)

    These Proceedings contain written versions of most of the lectures delivered at the 1987 CERN School of Computing. Five lecture series treated various aspects of data communications: integrated services networks, standard LANs and optical LANs, open systems networking in practice, and distributed operating systems. Present and future computer architectures were covered and an introduction to vector processing was given, followed by lectures on vectorization of pattern recognition and Monte Carlo code. Aspects of computing in high-energy physics were treated in lectures on data acquisition and analysis at LEP, on data-base systems in high-energy physics experiments, and on Fastbus. The experience gained with personal work stations was also presented. Various other topics were covered: the use of computers in number theory and in astronomy, fractals, and computer security and access control. (orig.)

  5. Report of the advisory panel on the prospects for e+e- colliders in the TeV range

    International Nuclear Information System (INIS)

    This is the concluding report of the Advisory Panel on the Prospects for e+e- Colliders in the TeV range, a panel set up by the CERN Long-Range Planning Committee chaired by C. Rubbia. The report covers general considerations, particle sources and the final focus and interaction point, before looking at various possible acceleration methods in some detail - normal rf linacs, superconducting acceleration structures, structures excited by opto-electrical switches, wake-field acceleration, and plasma beat-wave acceleration. It is concluded that one approach to a TeV collider, based on a normal conducting linear accelerator at a frequency of approximately 30 GHz and with a gradient of about 100 MeV/m, seems to give promise of leading to a real project in three to five years if enough manpower and money were invested in research and development. In the scheme outlined in the report, the drive power is obtained from an auxiliary beam of a few GeV, which in turn is accelerated by superconducting cavities identical to the ones now under construction for LEP 200. The panel also proposes that sufficient effort be devoted to continuing the research on more exotic schemes of acceleration, which in the longer term may lead to much higher gradients. The report was originally issued as CLIC note 38, and a complete list of these internal reports is given as an appendix. (orig.)

  6. Snapshots of CERN

    CERN Multimedia

    Rebecca Leam

    Art was the language of communication between science and the thousands of visitors attending CERN’s two photographic exhibitions in Italy and Spain in October. The artistic images of CERN’s Nobel Prize winners, Large Hadron Collider (LHC) machinery and detectors raised people's curiosity and helped to promote the understanding of particle physics.   The exhibition “Accelerating Nobels” at Genoa’s 7th Science Festival. The exhibition “Accelerating Nobels” attracted over 600’000 visitors during Genoa’s 7th annual Science Festival. It showed science photographer Volker Steger’s 21 portraits of physics Nobels holding their own impromptu drawings of their best discovery. “The theme of the festival was ‘The Future’. The exhibition illustrated the long history of particle physics discoveries at CERN which all lead to what the LHC is going to find, including probably more ...

  7. CERN selects Fujikura's radiation resistant fibre

    CERN Multimedia

    2007-01-01

    "Fujikura today announced that its radiation resistant single mode optical fibre has been selected by CERN, the European Laboratory for Particle Physics, to provide communication links within the world's largest particle accelerator - the Large hadron Collider (LHC) - near Genevan, Switzerland. (1/2 page)

  8. CERN set sights on an early LHC

    CERN Multimedia

    Hellemans, A

    1997-01-01

    CERN voted to advance the completion date of the Large Hadron Collider by three years, to 2005, while cutting the budget of some other projects. It is hoped that the unprecedented power of the $2-billion LHC will help prove the existence of the Higgs boson and other theoretically predicted particles.

  9. Torchwood sends inspection team to CERN

    CERN Multimedia

    Sherriff, Lucy

    2007-01-01

    "Torchwood's Captain Jack has been sighted at CERN's Large Hadron Collider. Does this mean that when it is switched on it is likely to open a rift under Cardiff from whence all manner of spooky things shall spring?" (1/2 page)

  10. Bosons & More: Celebrating CERN / Part 2

    CERN Multimedia

    Team, CERN

    2013-01-01

    The "Bosons & More" event for CERN people this evening celebrated the success of the Open Days, and the exceptional achievements of the Large Hadron Collider (LHC). The British progressive rock band the Alan Parsons Live Project lead the celebrations until late in the night.

  11. CERN selects Fujikura's radiation resistant fiber

    CERN Multimedia

    2007-01-01

    "Fujikura recently announced that its radiation resistant single mode optical fiber has been selected by CERN, the European Laboratory for Particle Physics, to provide communication links within the world's largest particle accelerator - the Large Hadron Collider (LHC) - near Geneva, Switzerland." (1/2 page)

  12. CERN signs agreement with New Zealand

    CERN Multimedia

    2003-01-01

    "New Zealand's particle physicists have joined the world's most ambitious scientific undertaking with the signing of a Memorandum of Understanding (MoU) between their government and CERN . This agreement formalises the participation of New Zealand scientists in the laboratory's Large Hadron Collider (LHC) project" (1 page).

  13. Milestone, Weighing 1430 Tons, Reached at CERN

    CERN Multimedia

    2008-01-01

    More on the subject of the Large Hadron Collider (see my last post, pointing to the very good Scientific American package). CERN announced today that the final piece of one of the main LHC particle detectors was at last safely lowered underground early this morning.

  14. Implementation of Stochastic Cooling Hardware at Fermilab's Tevatron Collider

    International Nuclear Information System (INIS)

    The invention of Stochastic cooling by Simon van der Meer made possible the increase in phase space density of charged particle beams. In particular, this feedback technique allowed the development of proton antiproton colliders at both CERN and Fermilab. This paper describes the development of hardware systems necessary to cool antiprotons at the Fermilab Tevatron Collider complex.

  15. Comparison of two approaches to linear collider design

    International Nuclear Information System (INIS)

    This paper reviews linear collider parameters. It aims at analyzing two specific design approachs - the ones for CLIC at CERN and for a TeV linear collider at SLAC - which appear to lead into remarkably different directions although they start from the same premises and try to respect the same boundary conditions. 19 refs

  16. Determination of W boson mass from the four quark decay in the DELPHI experiment at LEP; Mesure de la masse du boson W dans la desintegration a quatre quarks dans l'experience DELPHI au LEP

    Energy Technology Data Exchange (ETDEWEB)

    Duperrin, Arnaud [Universite Claude Bernard, 69 - Lyon (France)

    1999-04-20

    The accurate determination of W boson mass allows testing the coherence of standard model and imposing new constrains upon some of its parameters as for instance the Higgs boson mass. The W mass obtained by direct reconstruction of WW{yields}qq-bar qq-bar, was measured by means of the data recorded in 1997 and 1998 by DELPHI experimentat the center-of-mass energies 183 GeV and 189 GeV, for a total luminosity of 212 pb{sup -1} at the LEP collider of CERN. A neural network was used to label the signal what led to an efficiency and a selection accuracy of 86% and 80%, respectively. The number of the selected events among the data was 1710. By mass reconstruction, the jet multiplicity was let to vary free between four and eight jets. A new fast algorithm of kinematic fitting of the jets was developed to improve the mass resolution of the multi-jet events, by imposing the energy and momentum conservation. The association of jets has been carried out also by means of a neural network. The W boson mass was extracted starting from a probability fitting of the two-dimensional distribution provided by complete simulation and formed by the mean and the difference of two masses of W reconstructs. A technique of Monte Carlo re-weighting has been developed to obtain the simulation spectra for arbitrary M{sub W} values. The leading systematic uncertainties are studied by gathering a large number of e{sup +}e{sup -}{yields}Z{yields}qq-bar events and by merging them for obtaining events similar to the W pairs. The value of the W mass obtained from the data based on this probability is M{sub W} = 80.350{+-}0.099 (stat.) {+-} 0.038 (exp.) {+-} 0.056 (th.) {+-} 0.018 (LEP) GeV/c{sup 2}. This result is competitive and in good agreement with other determinations. The current world average mass of W boson is M{sub W} = 80.394 {+-} 0.042 GeV/c{sup 2}. This result, included in a global fitting of the electroweak data, constraints the standard Higgs boson to a mass lower than 262 Ge

  17. GERMANY AT CERN

    CERN Multimedia

    2001-01-01

    13 - 15 November 2001 Administration Building Bldg 60 - ground and 1st floor 09.00 hrs - 17.30 hrs OPENING CEREMONY 10h00 - 13 November GERMANY AT CERN Thirty-three German companies will be demonstrating their supplies and services offered for the construction of the Large Hadron Collider (LHC) and other key CERN programmes. The Industrial exhibition will be enriched with a display of objects of contemporary German art. The official German presentation is under the patronage of the Federal Minister of Education and Research (BMBF), Bonn. There follows : the list of exhibitors, the list of lectures to be given at the exhibition. A detailed programme will be available in due course at : your Divisional Secretariat, the Reception information desk, building 33, the exhibition. LIST OF EXHIBITORS Accel Instruments GmbH Representative: 1.1 Accel Instruments GmbH/CH-8754 Netsal apra-norm Elektromechanik GmbH Representative: 2.1 apra-norm s.n.c./F-67500 Haguenau Babcock Noell Nuclear GmbH Balcke-D&u...

  18. CERN Shuttle

    CERN Multimedia

    General Infrastructure Services Department

    2011-01-01

    As of Monday 21 February, a new schedule will come into effect for the Airport Shuttle (circuit No. 4) at the end of the afternoon: Last departure at 7:00 pm from Main Buildig, (Bldg. 500) to Airport (instead of 5:10 p.m.); Last departure from Airport to CERN, Main Buildig, (Bldg. 500), at 7:30 p.m. (instead of 5:40 p.m.). Group GS-IS

  19. Geneva University honours two CERN staff members

    CERN Multimedia

    2001-01-01

    Albert Hofmann Steve Myers On 8 June, two CERN staff members will receive Geneva University's highest distinction. On the proposal of the University's particle physicists, Steve Myers and Albert Hoffmann, who orchestrated LEP commissioning and operation and were instrumental in its success, will awarded the distinction of doctor honoris causa. The ceremony, interspersed with musical interludes, will be followed by a formal reception and is open to all. The Uni Dufour car park will be free to members of the public attending the ceremony. 8 June 2001 at 10.00 a.m. Uni Dufour, Auditoire Piaget 24, rue Général Dufour, Geneva.

  20. Electroweak symmetry breaking after LEP1 and LEP2

    CERN Document Server

    Barbieri, Riccardo; Rattazzi, Riccardo; Strumia, Alessandro; Barbieri, Riccardo; Pomarol, Alex; Rattazzi, Riccardo; Strumia, Alessandro

    2004-01-01

    In a generic 'universal' theory of electroweak symmetry breaking, non fine-tuned heavy new physics affects the low-energy data through four parameters, which include and properly extend the generally insufficient S and T. Only by adding the LEP2 data to the global electroweak fit, can all these four form factors be determined and deviations from the SM be strongly constrained. Several of the recently proposed models (little Higgs, gauge bosons in extra dimensions or Higgsless models in 5D) are recognized to be 'universal' in a straightforward way after a proper definition of the effective vector boson fields. Among various applications, we show that proposed Higgsless models in 5D, when calculable, do not provide a viable description of electroweak symmetry breaking in their full range of parameters.

  1. 6th IT First Tuesday@CERN

    CERN Multimedia

    François Grey

    2005-01-01

    Thursday 12 May, 17:30-19:30, Main Auditorium, CERN Data management in the 21st Century: the Petabyte challenge A Petabyte is a million Gigabytes, the equivalent of over 200,000 DVDs. That may seem like an enormous amount of data, but managing such quantities of data is a reality in the world of science, and is increasingly becoming an imperative in the world of business. This IT First Tuesday@CERN presents the Petabyte challenge, and some of the emerging solutions, from both scientific and commercial perspectives. For CERN's Large Hadron Collider, a Grid solution has been chosen to provide the necessary distributed storage capacity for the anticipated 15 Petabytes of data per year that this collider will produce. IBM is CERN's storage partner in the CERN openlab for DataGrid applications, and is testing the companies innovative TotalStorage SAN distributed filesystem in CERN's demanding IT environment. For Lausanne-based VisioWave, managing stored video data provides an extreme storage challenge. For D...

  2. New physics with the Compact Linear Collider

    CERN Multimedia

    Ellis, Jonathan Richard

    2001-01-01

    Investigating the 'strong' interactions between particles would be best investigated using a lepton-antilepton collider of energy 2 TeV or more. Plans for an accelerator of this type, called CLIC, have been underway at CERN for many years in collaboration with other accelerator laboratories (5 pages).

  3. Black Holes and the Large Hadron Collider

    Science.gov (United States)

    Roy, Arunava

    2011-01-01

    The European Center for Nuclear Research or CERN's Large Hadron Collider (LHC) has caught our attention partly due to the film "Angels and Demons." In the movie, an antimatter bomb attack on the Vatican is foiled by the protagonist. Perhaps just as controversial is the formation of mini black holes (BHs). Recently, the American Physical Society…

  4. From the LHC to Future Colliders

    DEFF Research Database (Denmark)

    De Roeck, A.; Ellis, J.; Grojean, C.;

    2010-01-01

    Discoveries at the LHC will soon set the physics agenda for future colliders. This report of a CERN Theory Institute includes the summaries of Working Groups that reviewed the physics goals and prospects of LHC running with 10 to 300/fb of integrated luminosity, of the proposed sLHC luminosity up...

  5. The LHC Physics Centre at CERN

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Although raw physics data is produced at CERN, thanks to the GRID its analysis is performed in various institutes worldwide. In addition, workshops, conferences and meetings take place all over the world. The physicist community is decentralized, and CERN must continue to provide intellectual leadership. The LHC Physics Centre is the tool that will make this possible.   Until the early days of LEP, a large part of the scientific activity related to CERN’s experiments was strongly centered at the Laboratory. Few places had the infrastructure to host activities such as the working groups preparing the Yellow Reports, and the limited access to information in the pre-web era made CERN the natural place to learn what was happening in the field. “I remember the days when we, the theorists, would come to CERN just to read the most recent preprints, which were reaching CERN's Library before we could get them in our institutes”, says Michelangelo Mangano, a member of the Theo...

  6. CERN's vacuums honoured to the full

    CERN Multimedia

    2002-01-01

    CERN's Cristoforo Benvenuti is awarded one of the most prestigious prizes in the world of vacuum techniques     Because we constantly run into such individuals, we tend to forget that CERN has specialists with world reputations. It takes the international prizes they win to remind us of the fact. One such prize, the American Vacuum Society (AVS)'s Gaede-Langmuir Award for 2002, has gone to Cristoforo Benvenuti, Leader of the Surfaces and Materials Technologies Group in EST Division. The award, conferred once every two years, is one of the leading prizes in the vacuum field. By coincidence, its very first winner was Pierre Auger, one of CERN's founding fathers, back in 1978. Cristoforo Benvenuti, a senior physicist who joined CERN in 1966, has been singled out for his work on getter technologies. These technologies made their name at CERN with the coming of LEP, where they were used for pumping the machine. Getter is a material with the property of capturing gas molecules and thereby actin...

  7. Gravitational mass of positron from LEP synchrotron losses

    CERN Document Server

    Kalaydzhyan, Tigran

    2015-01-01

    General relativity (GR) is the current description of gravity in modern physics. One of the cornerstones of GR, as well as Newton's theory of gravity, is the weak equivalence principle (WEP), stating that the trajectory of a freely falling test body is independent of its internal structure and composition. WEP is known to be valid for the normal matter with a high precision. However, due to the rarity of antimatter and weakness of the gravitational forces, the WEP has never been confirmed for antimatter. The current direct bounds on the ratio between the gravitational and inertial masses of the antihydrogen do not rule out a repulsive nature for the antimatter gravity. Here we establish an indirect bound of 0.13% on the difference between the gravitational and inertial masses of the positron (antielectron) from the analysis of synchrotron losses at the Large Electron-Positron collider (LEP). This is the first confirmation of the conventional gravitational properties of antimatter without additional assumption...

  8. CERN OVERVIEW animation

    CERN Multimedia

    Arzur Catel Torres

    2015-01-01

    This animation shows how the Large Hadron Collider (LHC) works. The film begins with an aerial view of CERN near Geneva, with outlines of the accelerator complex, including the underground Large Hadron Collider (LHC), 27-km in circumference. The positions of the four largest LHC experiments, ALICE, ATLAS, CMS and LHCb are revealed before we see protons travelling around the LHC ring. The proton source is a simple bottle of hydrogen gas. An electric field is used to strip hydrogen atoms of their electrons to yield protons. Linac 2, the first accelerator in the chain, accelerates the protons to the energy of 50 MeV. The beam is then injected into the Proton Synchrotron Booster (PSB), which accelerates the protons to 1.4 GeV, followed by the Proton Synchrotron (PS), which pushes the beam to 25 GeV. Protons are then sent to the Super Proton Synchrotron (SPS) where they are accelerated to 450 GeV. The protons are finally transferred to the two beam pipes of the LHC. The beam in one pipe circulates clockwise while ...

  9. Study of muon bundles from extensive air showers with the ALICE detector at CERN LHC

    Science.gov (United States)

    Shtejer, K.

    2016-05-01

    ALICE is one of four large experiments at the CERN Large Hadron Collider, specially designed to study particle production in ultra-relativistic heavy-ion collisions. Located 52 meters underground with 28 meters of overburden rock, it has also been used to detect muons produced by cosmic-ray interactions in the upper atmosphere. The large size and excellent tracking capability of the ALICE Time Projection Chamber are exploited to study the muonic component of extensive air showers. We present the multiplicity distribution of these atmospheric muons and its comparison with Monte Carlo simulations. The latest version of the QGSJET hadronic interaction model was used to simulate the development of the resulting air showers. High multiplicity events containing more than 100 reconstructed muons were also studied. Similar events have been studied in previous underground experiments such as ALEPH and DELPHI at LEP without satisfactory explanations for the frequency of the highest multiplicity events. We demonstrate that the high muon-multiplicity events observed in ALICE stem from primary cosmic rays with energies above 1016 eV and that the frequency of these events can be successfully described by assuming a heavy mass composition of primary cosmic rays in this energy range.

  10. Prototype steel-concrete LEP dipole magnet

    CERN Multimedia

    1981-01-01

    The magnetic field needed in the LEP dipole magnets was rather low, of a fraction of tesla. This lead to the conception of a novel yoke structure consisting of stacks of 1.5 mm thick low-carbon steel laminations spaced by 4.1 mm with the spaces filled with concrete. The excitation coils were also very simple: aluminium bars insulated by polyester boxes in this prototype, by glass-epoxy in the final magnets. For details see LEP-Note 118,1978 and LEP-Note 233 1980. See also 8111529,7908528X.

  11. Probing the Big Bang with LEP

    Science.gov (United States)

    Schramm, David N.

    1990-01-01

    It is shown that LEP probes the Big Bang in two significant ways: (1) nucleosynthesis, and (2) dark matter constraints. In the first case, LEP verifies the cosmological standard model prediction on the number of neutrino types, thus strengthening the conclusion that the cosmological baryon density is approximately 6 percent of the critical value. In the second case, LEP shows that the remaining non-baryonic cosmological matter must be somewhat more massive and/or more weakly interacting than the favorite non-baryonic dark matter candidates of a few years ago.

  12. ABS at the SPS and LEP

    CERN Document Server

    Wenninger, J

    1999-01-01

    LEP and SPS are large circular accelerators equiped with more than 100 orbit monitors and corrector dipoles in each plane. At the SPS orbit control is mainly used to minimize beam losses, while for LEP the orbit is a crucial parameter for lumonisity performance. Various algorithms and strategies have been developped for LEP to find "Golden Orbits" that optimize the dispersion and the beam emittances. Despite those differences, the two machines share a large amount of control software for beam steering. The experience and problems related to beam steering at such large machines will be presented. The limitations of the orbit control system sharing between the two machines will be reviewed.

  13. slice of LEP beamtube with getter strip

    CERN Multimedia

    1989-01-01

    A section of the LEP beam pipe. This is the chamber in which LEP's counter-rotating electron and positron beams travel. It is made of lead-clad aluminium. The beams circulate in the oval cross-section part of the chamber. In the rectangular cross-section part, LEP's innovative getter-strip vacuum pump is installed. After heating to purify the surface of the getter, the strip acts like molecular sticky tape, trapping any stray molecules left behind after the accelerator's traditional vacuum pumps have done their job.

  14. Aerial view of CERN under the snow

    CERN Multimedia

    1963-01-01

    In this photograph taken in the winter of 1963, CERN still looks quite bare under its mantle of snow. The Proton Synchrotron (PS), resembling a bicycle wheel in shape, had been in operation since the summer of 1959. A proposal had just been made for the site of CERN's second large project, the Intersecting Storage Rings (ISR): France was to house the world's first proton-proton collider. In September 1965, the French authorities signed an agreement making more than 40 hectares of land available for the extension of the CERN site established in Switzerland into French territory. The ISR project received final approval from the CERN Council in December 1965. The civil engineering work on the French part began in November 196

  15. Monitoring Control Applications at CERN

    CERN Document Server

    Bernard, F; Milcent, H; Petrova, L B; Varela, F

    2011-01-01

    The Industrial Controls and Engineering (EN-ICE) group [1] of the Engineering Department at CERN has produced, and is responsible for the operation of around 60 applications, which control critical processes in the domains of cryogenics, quench protection systems, power interlocks for the Large Hadron Collider and other subsystems of the accelerator complex. These applications require 24/7 operation and a quick reaction to problems. For this reason the EN-ICE group is presently developing the Monitoring Operation of cOntrols Networks (MOON) tool to detect, anticipate and inform of possible anomalies in the integrity of the applications. The tool builds on top of Simatic WinCC Open Architecture (WinCC OA) [2] SCADA and makes usage of the Joint COntrols Project (JCOP) [3] and the UNified INdustrial COntrol System (UNICOS) [4] Frameworks developed at CERN. The tool provides centralized monitoring and software management of the different elements integrating the control systems like Windows and L...

  16. A luminosity measurement at LEP using the L3 detector

    Energy Technology Data Exchange (ETDEWEB)

    Koffeman, E.N.

    1996-06-25

    To perform high precision measurements at particle colliders it is crucial to know the exact intensity of the colliding beams. In particle physics this quantity is generally referred to as the luminosity. The determination of the luminosity in one of the experiments (L3) is the topic of this thesis. The implementation and the use of a silicon strip detector in L3, will be described in detail. In chapter one the most important parameters measured at LEP are discussed, preceded by a short introduction to the Standard Model. The process generally used for luminosity measurements in electron positron colliders is small angle Bhabha scattering. This process is discussed at the end of chapter one. In chapter two the characteristics of the collider and the L3 experiment are given. Together with the signature of the small angle Bhabha scattering, these experimental conditions determine the specifications for the design of the luminosity monitor. The general features of silicon strip detectors for their application in high energy physics are presented in chapter three. Some special attention is given to the behaviour of the sensors used for the tracking detector in the luminosity monitor. The more specific design details of the luminosity monitor are constricted to chapter four. In chapter five the conversion from detector signals into ccordinates relevant for the analysis is explained. The selection of the small angle Bhabha scattering events and the subsequent determination of the luminosity, are presented in chapter six. Systematic uncertainties are carefully studied. Important for a good understanding of the Bhabha selection are the events where a photon is produced in the scattering process. These events are separately studied. In chapter seven a comparison is presented between the radiative events observed in the data and their modelling in the Bhlumi Monte Carlo programme. (orig.).

  17. A luminosity measurement at LEP using the L3 detector

    International Nuclear Information System (INIS)

    To perform high precision measurements at particle colliders it is crucial to know the exact intensity of the colliding beams. In particle physics this quantity is generally referred to as the luminosity. The determination of the luminosity in one of the experiments (L3) is the topic of this thesis. The implementation and the use of a silicon strip detector in L3, will be described in detail. In chapter one the most important parameters measured at LEP are discussed, preceded by a short introduction to the Standard Model. The process generally used for luminosity measurements in electron positron colliders is small angle Bhabha scattering. This process is discussed at the end of chapter one. In chapter two the characteristics of the collider and the L3 experiment are given. Together with the signature of the small angle Bhabha scattering, these experimental conditions determine the specifications for the design of the luminosity monitor. The general features of silicon strip detectors for their application in high energy physics are presented in chapter three. Some special attention is given to the behaviour of the sensors used for the tracking detector in the luminosity monitor. The more specific design details of the luminosity monitor are constricted to chapter four. In chapter five the conversion from detector signals into ccordinates relevant for the analysis is explained. The selection of the small angle Bhabha scattering events and the subsequent determination of the luminosity, are presented in chapter six. Systematic uncertainties are carefully studied. Important for a good understanding of the Bhabha selection are the events where a photon is produced in the scattering process. These events are separately studied. In chapter seven a comparison is presented between the radiative events observed in the data and their modelling in the Bhlumi Monte Carlo programme. (orig.)

  18. Z Physics at LEP 1. Vol. 3

    International Nuclear Information System (INIS)

    The contents of this final report from the Workshop on Z Physics at LEP can be divided into two parts. The first part, comprising Vols. 1 and 2, is a relatively concise but fairly complete handbook on the physics of e+e- annihilation near the Z peak (with normal LEP luminosity and unpolarized beams, appropriate for the first phase of LEP operation). The second part (Vol. 3) is devoted to a review of the existing Monte Carlo event generators for LEP physics. A special effort has been made to co-ordinate the different parts of this report, with the aim of achieving a systematic and balanced review of the subject, rather than having simply a collection of separate contributions. (orig.)

  19. Z physics at LEP 1. Vol. 2

    International Nuclear Information System (INIS)

    The contents of this final report from the Workshop on Z Physics at LEP can be divided into two parts. The first part, comprising Vols. 1 and 2, is a relatively concise but fairly complete handbook on the physics of e+e- annihilation near the Z peak (with normal LEP luminosity and unpolarized beams, appropriate for the first phase of LEP operation). The second part (Vol. 3) is devoted to a review of the existing Monte Carlo event generators for LEP physics. A special effort has been made to co-ordinate the different parts of this report, with the aim of achieving a systematic and balanced review of the subject, rather than having simply a collection of separate contributions. (orig.)

  20. LEP sees the end of the tunnel

    CERN Document Server

    2002-01-01

    After 14 months, which have seen the removal of 30,000 tonnes of material from the tunnel, the LEP dismantling operation has now been completed. LHC installation, which will be subject to new safety rules, can go ahead.

  1. CERN moves to http://home.cern

    CERN Multimedia

    2015-01-01

    A new top-level domain for CERN will be inaugurated next week, with the migration of the core website to http://home.cern.   The new home.cern webpage. The .cern top-level domain is intended for the exclusive use of CERN and its affiliates, and will soon be open for applications from within the community. Clear governance mechanisms for registration and management of .cern domains have been put in place. Applications for domains may be submitted by current members of the CERN personnel, and must be sponsored by a CERN entity such as a department, experiment, project or CERN-recognised experiment. For more information please refer to the registration policy. The acquisition of the .cern top-level domain was negotiated via ICANN’s new gTLD programme by a board comprising members of the CERN Legal Service, Communications group and IT department. .cern is one of over 1,300 new top-level domains that will launch over the coming months and years. The .cern domain nam...

  2. UK @ CERN

    CERN Multimedia

    FI Department

    2008-01-01

    17 – 18 November 2008 9.00 a.m. - 5.00 p.m. on Monday 17 November 9.00 a.m. - 5.00 p.m. on Tuesday 18 November Individual meetings will take place in the technicians’ or engineers’ offices. The companies will contact relevant users/technicians but anyone wishing to arrange an appointment with a specific company can contact Caroline Laignel (mailto:caroline.laignel@cern.ch, tel. 73722). A list of the companies is available from all departmental secretariats and on the web at: http://fi-dep.web.cern.ch/fi-dep/structure/memberstates/exhibitions_visits.htm List of companies: 1. Caburn MDC Europe Ltd. 2. Croft Engineering Services 3. Cryox Ltd. 4. Goodfellow Cambridge Ltd. 5. Gravatom Engineering Systems Ltd. 6. High Voltage Technology 7. Lilco Ltd. 8. Micro Metalsmiths Ltd. 9. Photek Ltd. 10. Shadow Robot Company 11. Sundance Multiprocessor Technology Ltd. 12. Tessella plc 13. Thermal Resources Management Ltd. 14. Torr Scientific Ltd. For further information please contact Mrs C. Laignel, FI-DI, tel. 7372...

  3. [The CERN and the megascience].

    Science.gov (United States)

    Aguilar Peris, José

    2006-01-01

    In this work we analyse the biggest particle accelerator in the world: the LHC (Large Hadron Collider). The ring shaped tunnel is 27 km long and it is buried over 110 meters underground, straddling the border betwen France and Switzerland at the CERN laboratory near Geneva. Its mission is to recreate the conditions that existed shortly after the Big-Bang and to look for the hypothesised Higgs particle. The LHC will accelerate protons near the speed of the light and collide them head on at an energy of to 14 TeV (1 TeV = 10(12) eV). Keeping such high energy in the proton beams requires enormous magnetic fields which are generated by superconducting electromagnets chilled to less than two degrees above absolute zero. It is expected that LHC will be inaugurated in summer 2007.

  4. Detectors for LEP: methods and techniques

    International Nuclear Information System (INIS)

    This note surveys detection methods and techniques of relevance for the LEP physics programme. The basic principles of the detector physics are sketched, as recent improvement in understanding points towards improvements and also limitations in performance. Development and present status of large detector systems is presented and permits some conservative extrapolations. State-of-the-art techniques and technologies are presented and their potential use in the LEP physics programme assessed. (Auth.)

  5. Determination of the LEP beam energy

    CERN Document Server

    Torrence, E

    2000-01-01

    This article describes the determination of the LEP beam energy above the production threshold for W boson pairs. A brief overview of the magnetic extrapolation method is presented which is currently used to determine the LEP beam energy to a relative precision of 2*10/sup -4 /. A new method for beam energy measurements based on an in-line energy spectrometer is presented, and current developments in the commissioning of this device are outlined. (2 refs).

  6. CERN agonizes over whether to keep up the hunt for the Higgs

    CERN Multimedia

    2000-01-01

    Senior managers at CERN were meeting as Nature went to press, to decide whether to fund a one-year extension for LEP, at an estimated cost of 100 million CHF, in a bid to confirm possible earlier sightings of the Higgs boson (3 paragraphs).

  7. Status of PACMAN Project at CERN

    CERN Document Server

    Catalan-Lasheras, Nuria; Modena , Michele

    2015-01-01

    Though the Large Hadron Collider (LHC) at CERN is just at the start of a program expected to run for 20 additional years, CERN is studying the next generation of colliders, like the Compact Linear Collider (CLIC). This project proposes an electron-positron collider with a length close to 50 km and with a centre of mass energy of 3 TeV at the collision point. One of the main challenges is the sub-micrometric size of the beams, down to a few nanometres at the interaction point. As a consequence, the accelerator will require unprecedented nanometric tolerances of beam alignment. A series of several thousands components will have to be assembled, aligned at the micrometre level and most critically, stabilized actively at the nanometre level. PACMAN, a study on Particle Accelerator Components Metrology and Alignment to the Nanometre scale, is a Marie Curie Program supported by the European Commission (FP7 Program), creating a network of 16 Academic and Industrial Partners. The project is hosted at CERN and it offe...

  8. A busy week for Arts@CERN

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    Last week, Semiconductor – the winners of the Collide@CERN Ars Electronica award for 2015 – and artists Francesco Mariotti and José­-Carlos Mariátegui visited CERN and met the scientists.   Ruth Jarman (left) and Joe Gerhardt (right) of Semiconductor with Peter Jenni, one of the scientists they met during their visit to ATLAS.   Just a few weeks ago, Ruth Jarman and Joe Gerhardt, two English artists collaborating under the name Semiconductor, were awarded the Collide@CERN Ars Electronica prize for 2015. Last week, they came on their first visit to CERN to meet the scientists and select their scientific partner in preparation for their residency. They will soon begin a two-month residency at CERN before going to Linz (Austria), where they will spend a month at the Ars Electronica Futurelab. During their residency, the artists aim to create a digital artwork elaborating on the n...

  9. SUSY Without Prejudice at Linear Colliders

    CERN Document Server

    Rizzo, Thomas G

    2008-01-01

    We explore the physics of the general CP-conserving MSSM with Minimal Flavor Violation, the pMSSM. The 19 soft SUSY breaking parameters are chosen so to satisfy all existing experimental and theoretical constraints assuming that the WIMP is the lightest neutralino. We scan this parameter space twice using both flat and log priors and compare the results which yield similar conclusions. Constraints from both LEP and the Tevatron play an important role in obtaining our final model samples. Implications for future TeV-scale $e^+e^-$ linear colliders(LC) are discussed.

  10. CERN: Exploring the frontiers of knowledge

    CERN Multimedia

    CERN video productions

    2011-01-01

    CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. We conduct fundamental research in physics to study the basic constituents of matter — the elementary particles. By studying what happens when very energetic particles collide, physicists can learn more about the laws of nature. Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 20 Member States.

  11. CERN comes under fresh financial pressure

    CERN Multimedia

    Dickson, D

    1996-01-01

    Germany's decision to effect a 10% cut in its annual subscription to the Large Hadron Collider (LHC) in 1997 has added to the financial problems of the European Laboratory for Particle Physics (CERN), Geneva, Switzerland. Reduced European contributions will have a crucial impact on the planned construction and completion of LHC. Proposals for non-European membership to reduce the financial burden on CERN members is doubtful in the current political context. The German move hints at a reappraisal of the funding projections for LHC.

  12. Computer Security: Security operations at CERN (4/4)

    CERN Document Server

    CERN. Geneva

    2012-01-01

    Stefan Lueders, PhD, graduated from the Swiss Federal Institute of Technology in Zurich and joined CERN in 2002. Being initially developer of a common safety system used in all four experiments at the Large Hadron Collider, he gathered expertise in cyber-security issues of control systems. Consequently in 2004, he took over responsibilities in securing CERN's accelerator and infrastructure control systems against cyber-threats. Subsequently, he joined the CERN Computer Security Incident Response Team and is today heading this team as CERN's Computer Security Officer with the mandate to coordinate all aspects of CERN's computer security --- office computing security, computer centre security, GRID computing security and control system security --- whilst taking into account CERN's operational needs. Dr. Lueders has presented on these topics at many different occasions to international bodies, governments, and companies, and published several articles. With the prevalence of modern information technologies and...

  13. Klystron switching power supplies for the Internation Linear Collider

    Energy Technology Data Exchange (ETDEWEB)

    Fraioli, Andrea; /Cassino U. /INFN, Pisa

    2009-12-01

    The International Linear Collider is a majestic High Energy Physics particle accelerator that will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. ILC will complement the Large Hadron Collider (LHC), a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, by producing electron-positron collisions at center of mass energy of about 500 GeV. In particular, the subject of this dissertation is the R&D for a solid state Marx Modulator and relative switching power supply for the International Linear Collider Main LINAC Radio Frequency stations.

  14. Physics motivations for future CERN accelerators

    CERN Document Server

    de Roeck, A; Gianotti, F; de Roeck, Albert; Ellis, John; Gianotti, Fabiola

    2001-01-01

    We summarize the physics motivations for future accelerators at CERN. We argue that (a) a luminosity upgrade for the LHC could provide good physics return for a relatively modest capital investment, (b) CLIC would provide excellent long-term perspectives within many speculative scenarios for physics beyond the Standard Model, (c) a Very Large Hadron Collider could provide the first opportunity to explore the energy range up to about 30 TeV, (d) a neutrino factory based on a muon storage ring would provide an exciting and complementary scientific programme and a muon collider could be an interesting later option.

  15. 欧洲核子中心汇聚全球的努力筹划未来的巨大环型对撞机%CERN Promote the Wide International Collaboration for Building a Huge Future Circular Collider

    Institute of Scientific and Technical Information of China (English)

    钱思进

    2014-01-01

    结合2014年2月参加“对未来环型对撞机研究的启动会议”的见闻,介绍了全球高能物理界正在讨论如何通过广泛国际合作、在欧洲核子中心(CERN)建造未来环形高能加速器和粒子对撞机的新动态,简要回顾了历史上高能加速器和对撞机建设的经验和教训,摘编了与会者提出的相关见解和建议,希望中国高能物理的长远发展可从中借鉴和参考.

  16. China and CERN renew their Co-operation Agreement

    CERN Multimedia

    2004-01-01

    Dr. Liu Yanhua, Chinese Vice Minister of Science and Technology, and Dr. Robert Aymar, Director-General of CERN, sign a new Co-operation Agreement between the Government of the People's Republic of China and CERN. During his visit to CERN on 17 February, Liu Yanhua, Vice Minister of Science and Technology of the People's Republic of China, signed a new Co-operation Agreement with the Laboratory. The Agreement, which is valid for a period of five years and renewable, lays down the framework for the development of scientific and technological co-operation between CERN and China. This includes China's participation, as a non-Member State, in CERN's research projects as well as its main programmes. Robert Aymar and Liu Yanhua underlined that this Agreement will provide an excellent framework for close co-operation on the LHC Programme and Grid and accelerator technologies. Scientific co-operation between China and CERN is nothing new, as Chinese physicists already took part in the LEP experiments. Today, CERN's C...

  17. High energy accelerator and colliding beam user group

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This report discusses the following topics: OPAL experiment at LEP; D{phi} experiment at Fermilab; deep inelastic muon interactions at TEV II; CYGNUS experiment; final results from {nu}{sub e}{sup {minus}e} elastic scattering; physics with CLEO detector at CESR; results from JADE at PETRA; rare kaon-decay experiment at BNL; search for top quark; and super conducting super collider activities.

  18. 20 years ago: first collisions (at LEP)

    CERN Multimedia

    2009-01-01

    It’s been 20 years since the first electron positron collision at LEP, and I have to confess to a little self-indulgence in my message this week. Back then I was a member of the OPAL collaboration, the first to see collisions at LEP just before midnight on 13 August 1989 and almost exactly one month after the first circulating beam. It was a historic moment, and the atmosphere in the OPAL control room, 100 metres underground, was one of anticipation and excitement. We reported back to the LEP control room, champagne duly arrived, and over the next few hours, all the experiments were recording data. The pilot run was as smooth as it could be, and within weeks we were announcing new physics. It’s interesting to contrast the start-up of LEP with that of the LHC. With the benefit of hindsight, LEP seems to have got going without a hitch, and indeed it was a smooth start. We circulated beam on 14 July, much to the joy of one of our host states, and it was just a month ...

  19. Bienvenue au CERN !

    CERN Multimedia

    CERN Press Office. Geneva

    1998-01-01

    CERN, the Laboratory which invented the World-Wide Web has re-invented its public Web site. The new face of CERN has gone live at http://www.cern.ch/ Public . CERN's new Web pages have been designed to give visitors an informative introduction to the fascinating world of particle physics. For those whose whirl around the Web only allows a short stop, there's the 'CERN in two minutes' page.

  20. Color reconnection at future e+e- colliders

    International Nuclear Information System (INIS)

    The effects of color reconnection (CR) at e+e- colliders are revisited, with focus on recently developed CR models. The new models are compared with the LEP2 measurements for e+e- → W+W- → q1 anti q2q3 anti q4 and found to lie within their limits. Prospects for constraints from new high-luminosity e+e- colliders are discussed. The novel arena of CR in Higgs decays is introduced, and it is illustrated by shifts in angular correlations that would be used to set limits on a potential CP-odd admixture of the 125 GeV Higgs state. (orig.)

  1. The standard model Higgs search at the large hadron collider

    Indian Academy of Sciences (India)

    Satyaki Bhattacharya; on behalf of the CMS and the ATLAS Collaborations

    2007-11-01

    The experiments at the large hadron collider (LHC) will probe for Higgs boson in the mass range between the lower bound on the Higgs mass set by the experiments at the large electron positron collider (LEP) and the unitarity bound (∼ 1 TeV). Strategies are being developed to look for signatures of Higgs boson and measure its properties. In this paper results from full detector simulation-based studies on Higgs discovery from both ATLAS and CMS experiments at the LHC will be presented. Results of simulation studies on Higgs coupling measurement at LHC will be discussed.

  2. Collider physics for the late 1980's

    Energy Technology Data Exchange (ETDEWEB)

    Hinchliffe, I.

    1987-02-27

    Topics in the Standard Model of strong and electroweak interactions and how these topics are relevant for the high energy colliders are discussed. Radiative corrections in the Glashow-Weinberg-Salam model are discussed, stressing how these corrections may be measured at LEP and the SLC. CP violation is discussed, followed by a discussion of the Higgs boson and the searches which can be carried out for it. Some features of quantum chromodynamics are discussed which are relevant to hadron colliders. Some of the problems which the Standard Model does not solve are discussed. 115 refs., 53 figs. (LEW)

  3. UK @ CERN

    CERN Multimedia

    FI Department

    2008-01-01

    17 – 18 November 2008 9.00 a.m. - 5.00 p.m. on Monday 17 November 9.00 a.m. - 5.00 p.m. on Tuesday 18 November Individual meetings will take place in the technicians’ or engineers’ offices. The companies will contact relevant users/technicians but anyone wishing to arrange an appointment with a specific company can contact Caroline Laignel (caroline.laignel@cern.ch, tel. 73722). A list of the companies is available from all departmental secretariats and on the web here. List of companies: 1. Caburn MDC Europe Ltd. 2. Croft Engineering Services 3. Cryox Ltd. 4. Goodfellow Cambridge Ltd. 5. Gravatom Engineering Systems Ltd. 6. High Voltage Technology 7. Lilco Ltd. 8. Micro Metalsmiths Ltd. 9. Photek Ltd. 10. Shadow Robot Company 11. Sundance Multiprocessor Technology Ltd. 12. Tessella plc 13. Thermal Resources Management Ltd. 14. Torr Scientific Ltd. For further information please contact Mrs C. Laignel, FI-DI, tel. 73722.

  4. Prototype superconducting radio-frequency cavity for LEP

    CERN Multimedia

    1985-01-01

    This niobium superconducting cavity was part of the prototype stages for an upgrade to LEP, known as LEP-2. Superconducting cavities would eventually replace the traditional copper cavities and allow beam energies of 100 GeV.

  5. Welcome to the CERN OPENDAYS: Our Universe is Yours

    CERN Multimedia

    2013-01-01

    CERN is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics: finding out what the Universe is made of and how it works. At CERN, large and highly complex scientific instruments are used to study the basic constituents of matter: the fundamental particles. By studying what happens when these particles collide, physicists further our understanding of the laws of Nature

  6. Canadian ATLAS data center to support CERN's LHC

    CERN Multimedia

    2006-01-01

    "The biggest science experiment in history is currently underway at the world-famous CERN labs in Switzerland, and Canada is poised to play a critical role in its success. Thanks to a $10.5 million investment announced by the Canada Foundation for Innovation (CFI), an ultra-sophisticated computing facility -- the ATLAS Data Center -- will be created to support the ATLAS project at CERN's Large Hadron Collider (LHC)." (1 page)

  7. GERMANY AT CERN

    CERN Multimedia

    2001-01-01

    13 - 15 November 2001 Administration Building Bldg 60 - ground and 1st floor 09.00 hrs - 17.30 hrs OPENING CEREMONY 10h00 - 13 November Thirty-three German companies will be demonstrating their supplies and services offered for the construction of the Large Hadron Collider (LHC) and other key CERN programmes. The Industrial exhibition will be enriched with a display of objects of contemporary German art. The official German presentation is under the patronage of the Federal Minister of Education and Research (BMBF), Bonn. There follows : the list of exhibitors, the list of lectures to be given at the exhibition. A detailed programme will be available in due course at : your Divisional Secretariat, the Reception information desk, building 33, the exhibition. LIST OF EXHIBITORS Accel Instruments GmbH Representative: Accel Instruments GmbH/CH-8754 Netsal apra-norm Elektromechanik GmbH Representative: apra-norm s.n.c./F-67500 Haguenau Babcock Noell Nuclear GmbH Balcke-Dürr Energietec...

  8. GERMANY AT CERN

    CERN Multimedia

    2001-01-01

    13 - 15 November 2001 Administration Building Bldg 60 - ground and 1st floor 09.00 hrs - 17.30 hrs OPENING CEREMONY 10h00 - 13 November Thirty-three German companies will be demonstrating their supplies and services offered for the construction of the Large Hadron Collider (LHC) and other key CERN programmes. The Industrial exhibition will be enriched with a display of objects of contemporary German art. The official German presentation is under the patronage of the Federal Minister of Education and Research (BMBF), Bonn. There follows : the list of exhibitors, the list of lectures to be given at the exhibition. A detailed programme will be available in due course at : your Divisional Secretariat, the Reception information desk, building 33, the exhibition. LIST OF EXHIBITORS Accel Instruments GmbH Representative: Accel Instruments GmbH/CH-8754 Netsal apra-norm Elektromechanik GmbH Representative: apra-norm s.n.c./F-67500 Haguenau Babcock Noell Nuclear GmbH Balcke-Dürr Energiet...

  9. At LEP, a new Physics. The dark matter

    International Nuclear Information System (INIS)

    The starting of LEP (European Large Electron-Positron storage rings) took place, in July 1989 and the 5 reports introduced during the 21th Summer School on Particle Physics (Ecole de Gif) locate, after a rapid recall of standard model, the problems that LEP will have to resolve in a more or less long time, LEP 100 or LEP 200. These reports are indexed separately

  10. Measure of the e+e-→bb Cross Section at the LEP Energies

    International Nuclear Information System (INIS)

    In the present work I analyse the data collected during 1990 by the L3 detector, situated in the electron-positron collider LEP. After selecting the events e''+e''-→ bb through their semileptonic decays into muons, I calculate the cross section for the process e''+e''- → bb at different energy points around the mass of the vectorial boson Z, and I measure some parameters of the Standard Model, namely, the Br(b→μ ),Γzn-→bb/Γzn→had and Γzn→bbΓzn→e''+e''-. (Author) 26 refs

  11. Measurement of hadronic final states with the L3 detector at LEP

    International Nuclear Information System (INIS)

    The measurement of σhad and Rb with the L3 detector at the LEP collider at centre-of-mass energies from 192 GeV to 207 GeV are presented. From the measurements are determined the vector and axial vector couplings of the Z boson to the bottom quarks. The vector and axial vector couplings probe the validity of the Standard Model of elementary particle physics. Deviations of the measurements from the Standard Model prediction are discussed in the framework of extended models. (orig.)

  12. The SAT calorimeter of the DELPHI experiment at LEP; results of a module test

    Energy Technology Data Exchange (ETDEWEB)

    Alvsvag, S.J.; Eide, B.; Frodesen, A.G.; Grung, B.; Iversen, P.S.; Klovning, A.; Kvaavik, D.; Lillestoel, E.; Lillethun, E.; Maeland, O.A.; Pettersen, T.E.; Rongved, R.; Topphol, A.K. (Bergen Univ. (Norway). Dept. of Physics)

    1990-05-10

    The construction of an electromagnetic calorimeter using scintillating plastic fibres and lead plates is described. The calorimeter is part of the Small Angle Tagger (SAT) of the DELPHI experiment at the LEP collider, recording high-energy electrons, positrons and photons. Results from a test of a module of similar construction are presented. The module was found to have a linear energy response when exposed to electrons of 10-70 GeV, with an energy resolution given by {sigma}/E(%) = (1.16{sup 2}+(11.4/{radical}E(GeV)){sup 2}){sup 1/2}. (orig.).

  13. New CKM-related studies on b decays in the DELPHI experiment at LEP

    CERN Document Server

    Mitaroff, Winfried A

    2003-01-01

    The e-e+ collider LEP, running at sqrt{s} = m(Z0), has been a copious source of b-hadrons produced in decays Z0 -> b \\b. We present recent studies using up to 4*10^6 hadronic Z0 decays acquired by the DELPHI detector between 1992 and 2000. They rely on efficient particle identification, precise track and vertex reconstruction and sophisticated data analysis algorithms. Presented are: a new measurement of the CKM matrix element |V_cb| in the semileptonic exclusive decays B0_d -> D*+ l- \

  14. LHC explores what LEP hinted at: CP-violating type-I 2HDM

    OpenAIRE

    Mader, Wolfgang; Park, Jae-hyeon; Pruna, Giovanni Marco; Stöckinger, Dominik; Straessner, Arno

    2012-01-01

    The Large Hadron Collider is shown to have great scope for a light charged Higgs discovery, in the context of the CP-violating type-I two Higgs doublet model. This scenario with similar masses of $H^\\pm$ and W was suggested by the puzzling departure from charged current lepton universality found in the LEP data. With the lightest neutral Higgs mass set to 125 GeV, the charged-neutral Higgs associated production mechanism can cause a significant excess in the $\\tau \

  15. High Energy Accelerator and Colliding Beam User Group: Progress report, March 1, 1988--February 28, 1989

    International Nuclear Information System (INIS)

    This report discusses work carried out by the High Energy Accelerator and Colliding Beam User Group at the University of Maryland. Particular topics discussed are: OPAL experiment at LEP; deep inelastic muon interactions; B physics with the CLEO detector at CESR; further results from JADE; and search for ''small'' violation of the Pauli principle

  16. Measurement of the W mass at LEP

    CERN Document Server

    Przysiezniak, H

    2000-01-01

    The mass of the W boson is measured using W pair events collected with the ALEPH, DELPHI, L3 and OPAL detectors at LEP2. Three methods are used: the cross section method, the lepton energy spectrum method and the direct reconstruction method, where the latter is described more in detail. For data collected at E/sub cm/=161, 172 and 183 GeV, the following combined preliminary result is obtained: M/sub W//sup LEP/=80.37+or-0.08 GeV/c/sup 2/. (5 refs).

  17. Z' signal from the LEP2 data

    OpenAIRE

    Gulov, A. V.; Skalozub, V. V.

    2006-01-01

    The many-parametric fit of the LEP2 data on e^+e^-\\to e^+e^-, \\mu^+\\mu^-, \\tau^+\\tau^- processes is performed to estimate signals of the Abelian Z'-boson beyond the standard model. The model-independent relations between the Z' couplings to the standard model particles allow to describe the Z' effects in lepton processes by 4 independent parameters. No signal is found by the complete LEP2 data set, and the 1.3\\sigma signal is detected by the fit of the backward bins. The Z' couplings to the v...

  18. Quantum chromodynamics studies at LEP2

    Indian Academy of Sciences (India)

    Sunanda Banerjee

    2000-07-01

    Several studies have been made to the hadronic final states in +- collisions at LEP. Studies of the annihilation process at LEP2 have given rise to results on jet rate, event shape, heavy flavour production, inclusive momentum spectra, Bose–Einstein correlation and colour reconnection effects. Event shape studies have given rise to accurate determination of the strong coupling constant s using $\\mathcal{O}(^{2}_{s})$ with resummed leading and next-to-leading log calculation and also with power law corrections. Studies of 2-photon processes have yielded results on cross-section, heavy flavour production, photon structure function and ** scattering.

  19. Pairs of charged heavy fermions from an $SU(3)_{L}(-)U(1)_{N}$ model at $e^{+}e^{-}$ colliders

    CERN Document Server

    Cieza-Montalvo, J E; 10.1103/PhysRevD.67.075022

    2003-01-01

    We investigate the production, backgrounds, and signatures of pairs of charged heavy fermions using the SU(3)/sub L/(-)U(1)/sub N/ electroweak model in e/sup +/e/sup -/ colliders (Next Linear Collider and CERN Linear Collider). We also analyze the indirect evidence for a boson Z'. (23 refs).

  20. Delay in Europe could mean extra year for U.S. Collider

    CERN Multimedia

    Cho, Adrian

    2007-01-01

    "Physicists were hardly surprised when officials at the European lab CERN announced last week that the world's new highest-energy atom smasher, the Large Hadron Collider (LHC), will not start up in November as planned..."(1 page)

  1. Beam loss mechanisms in relativistic heavy-ion colliders

    CERN Document Server

    Bruce, Roderik; Gilardoni, S; Wallén, E

    2009-01-01

    The Large Hadron Collider (LHC), the largest particle accelerator ever built, is presently under commissioning at the European Organization for Nuclear Research (CERN). It will collide beams of protons, and later Pb82+ ions, at ultrarelativistic energies. Because of its unprecedented energy, the operation of the LHC with heavy ions will present beam physics challenges not encountered in previous colliders. Beam loss processes that are harmless in the presently largest operational heavy-ion collider, the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory, risk to cause quenches of superconducting magnets in the LHC. Interactions between colliding beams of ultrarelativistic heavy ions, or between beam ions and collimators, give rise to nuclear fragmentation. The resulting isotopes could have a charge-to-mass ratio different from the main beam and therefore follow dispersive orbits until they are lost. Depending on the machine conditions and the ion species, these losses could occur in loca...

  2. Orbit Steering and Central Frequency for LEP2 Energy Calibration

    CERN Document Server

    Wenninger, J

    2000-01-01

    "The central frequency is an important parameter of the LEP beam energy model. It is a direct measurementof the LEP circumference and is used to evaluate the contribution of the quadrupoles to field integral relevant forthe LEP beam ebergy. Its evolution over a run is tracked using direct frequency measurementscombined with radial beam position measurements in the LEP arcs.The influence of orbit corrections on the central frequency measurement techniques was evaluatedand a model allowing to correct for changes of corrector settings was developped.The central frequency data for the LEP2 runs between 1996 and 1999 was re-analysed to includecorrections due to the closed orbit steering."

  3. Lessons on Ancient China for LEP Adolescents.

    Science.gov (United States)

    Wigglesworth, Pierre Giles

    A unit in a Glendale, California sixth grade social studies curriculum is presented as a model for addressing two problems in the instruction of the growing population of limited English-proficient (LEP) students: (1) inadequate teacher training; and (2) shortage of appropriate, effective instructional materials. For the curriculum segment on…

  4. b-Hadron Physics at LEP

    OpenAIRE

    Barker, G. J.

    2002-01-01

    A personal overview of the current status of physics results from LEP using b-hadrons is presented. Emphasis is placed on those areas where analyses are not yet finalised and there remains significant activity. Results are presented in the areas of b-quark fragmentation, b-hadron lifetimes, charm counting in b-decays and Vcb.

  5. Maailmas lokkab globaalne terrorism / Ando Leps

    Index Scriptorium Estoniae

    Leps, Ando, 1935-

    2002-01-01

    29. märtsil moodustati Riias ülemaailmsel kuritegevuse- ja terrorismivastasel foorumil Läänemerega piirnevate riikide Kuritegevuse- ja Terrorismivastane Foorum. Võeti vastu põhikiri, nimetati ametisse juhatus ja büroo direktor. Foorumi üheks kaasesimeheks valiti Ando Leps. Autor: Keskerakond. Parlamendisaadik

  6. Demonstration model of LEP bending magnet

    CERN Multimedia

    CERN PhotoLab

    1981-01-01

    To save iron and raise the flux density, the LEP bending magnet laminations were separated by spacers and the space between the laminations was filled with concrete. This is a demonstration model, part of it with the spaced laminations only, the other part filled with concrete.

  7. Jet Physics at LEP and SLC

    OpenAIRE

    Stefano CataniINFN Firenze

    2014-01-01

    Experimental results on jet physics at LEP and SLC are reviewed and compared with perturbative QCD predictions. The discussion includes determinations of the strong coupling $\\as$, measurements of event shape distributions and jet cross sections, studies of subjet multiplicities and tests of QCD coherence.

  8. Globaliseeruv kuritegevus ja terror / Ando Leps

    Index Scriptorium Estoniae

    Leps, Ando, 1935-

    2002-01-01

    29. märtsil moodustati Riias ülemaailmsel kuritegevuse- ja terrorismivastasel foorumil Läänemerega piirnevate riikide Kuritegevuse- ja Terrorismivastane Foorum. Võeti vastu põhikiri, nimetati ametisse juhatus ja büroo direktor. Foorumi üheks kaasesimeheks valiti Ando Leps. Autor: Keskerakond. Parlamendisaadik

  9. Hangout with CERN: Welcome to CERN (S01E01)

    CERN Multimedia

    Kahle, Kate

    2012-01-01

    In this first Hangout with CERN "Welcome to CERN" ATLAS physicist Steven Goldfarb, CERN theorist Alvaro De Rujula and Mick Storr from the CERN education group introduce CERN and answer some of the questions received via #askCERN on Twitter and Google+. Recorded live on 1st November 2012.

  10. CERN's LHC is awarded the 2012 EPS Edison Volta Prize

    CERN Document Server

    CERN Bulletin

    2012-01-01

    The European Physical Society (EPS), the Centro di Cultura Scientifica “Alessandro Volta” and Edison S.p.A. have awarded the 2012 EPS Edison Volta Prize for outstanding contributions to physics to three CERN physicists.   The award was given to: • Rolf-Dieter Heuer, CERN Director-General, • Sergio Bertolucci, CERN Director for Research and Computing, • Stephen Myers, CERN Director for Accelerators and Technology, for having led - building on decades of dedicated work by their predecessors - the culminating efforts in the direction, research and operation of the CERN Large Hadron Collider (LHC), which resulted in many significant advances in high energy particle physics, in particular, the first evidence of a Higgs-like boson in July 2012. To learn more, check out e-EPS News.

  11. Catalysed fusion: a very different book about CERN

    CERN Multimedia

    CERN Library

    2013-01-01

    Not many books get reviews resulting in headlines like "Steamy novel challenges CERN's serious image", "Love and death at CERN" and so on. But Francis Farley's book "Catalysed Fusion" does not leave its readers untouched.   Those of you who have been around some time will know Farley from when he worked at CERN. For "newcomers", Farley is a well-known physicist who put together the first experiment on the anomalous magnetic moment of the muon and has since taken part in all the experiments relating to this phenomenon. The back cover of his book reads: "A sizzling romance and a romp with subatomic particles at CERN. Love, discovery and adventure in the city where nations meet and beams collide. Life in a large laboratory. As always, the challenges are the same. Who leads? Who follows? Who succeeds? Who gets the credit? Who gets the women or the men? Young Jeremy arrives in CERN and joins the quest ...

  12. Experiments at CERN in 1985

    International Nuclear Information System (INIS)

    This book is a compilation of the current experimental program at CERN. The experiments listed are being performed at one of the following machines: the Super Proton Synchrotron (SPS), the Proton Synchrotron (PS) and the Synchro-Cyclotron (SC). The four experiments to be done by means of the Large Electron Positron machine (LEP) are also listed. The schematic layouts of beams and experiments at the various machines are given in the beginning of the report. The experiment goals and methods are briefly described and a schematic layout of the apparatus is included. Lists of participants and their institutions are also given. The status of the experiments (preparation, data-taking, completed) corresponds to the situation as of 1st November, 1985. ''Completed'' means only that data-taking is finished, not necessarily the analysis of the results; this status is kept for two years and then the experiment is removed from the catalogue. A complete list of all experiments published in this book since 1975 is given at the end of the catalogue. (orig./HSI)

  13. Experiments at CERN in 1988

    International Nuclear Information System (INIS)

    This book is a compilation of the current experimental programme at CERN. The experiments listed are being performed at one of the following machines: The Super Proton Synchrotron (SPS), the Proton Synchrotron (PS) and the Synchro Cyclotron (SC). The four experiments planned for the Large Electron Positron machine (LEP) are also listed. The schematic layouts of beams and experimental areas at the different machines appear at the beginning of the report. The experiments are briefly described and a schematic layout of each apparatus is included together with lists of participants and institutions. The status of the experiments (preparation/data-taking/completed) corresponds to the situation at the end of 1988. The 'completed' status means that data-taking is finished, not necessarily the analysis of the results; this status is kept for two years and then the experiment is removed from the catalogue. A complete list of all the experiments published in these books since 1974 is given at the end. (orig./HSI)

  14. CERN's 50th anniversary open day attracts record number of visitors

    CERN Multimedia

    Patrice Loiez

    2004-01-01

    Some of the biggest attractions were the huge detectors under construction for the Large Hadron Collider. Such tours helped the visitors gain a sense of the scale of CERN's work - and even those who already had some notion of CERN were awed by the gigantic detectors, caverns, and tunnels.

  15. Doing business with CERN

    CERN Multimedia

    2015-01-01

    The Procurement Service, in collaboration with the Communications group’s Design team, has recently launched a new information campaign targeted at companies wishing to supply their products and services to CERN. This campaign comprises:   A brochure, available in hard and soft copy:  http://procurement.web.cern.ch/brochures/doing-business-with-cern.   A 6-minute video overview: https://procurement-dev.web.cern.ch/doing-business-with-cern. This campaign is intended for Member State firms with whom CERN is yet to do business. The key objectives are: To emphasise that CERN can be considered a major customer across a wide range of activities;   To present CERN’s procurement procedures in a dynamic and digestible way;   To highlight the information available on CERN’s procurement website: http://procurement.web.cern.ch. Furthermore, a new section called “Having a contract with CERN” is also now ava...

  16. Virgin Galactic explores CERN

    CERN Multimedia

    2016-01-01

    Virgin Galactic visited CERN with a group of future astronauts and Sir Richard Branson. During their visit the group was shown around various experiments, including the Globe, SM18, AMS and the CERN Control Centre.

  17. CERN Shop Christmas Sale

    CERN Multimedia

    Visits & Exhibition Service/ETT-VE

    2001-01-01

    11-13.12.2001 Looking for Christmas present ideas? Come to the Reception Shop Special Stand in Meyrin, Main Building, ground floor, from Tuesday 11 to Thursday 13 December from 10.30 to 16.00. CERN Calendar 10.- CERN Sweat-shirts(M, L, XL) 30.- CERN T-shirt (M, L, XL) 20.- New CERN silk tie (2 colours) 35.- Fancy silk tie (blue, bordeau) 25.- Silk scarf (light blue, red, yellow) 35.- Swiss army knife with CERN logo 25.- CERN watch 25.- CERN baseball cap 15.- CERN briefcase 15.- Book 'Antimatter' (English) 35.- Book 'How the web was born' (English) 25.- The Search for Infinity (French, Italian, English, German) 40.-   If you miss this special occasion, the articles are also available at the Reception Shop in Building 33 from Monday to Saturday between 08.30 and 17.30 hrs.

  18. Signing of the agreement between CERN and the United States in 1997

    CERN Multimedia

    1997-01-01

    Signing of the agreement between CERN and the United States for a contribution of $531 million to the Large Hadron Collider (LHC) project. The agreement was signed by Matha Krebs, Director of the Office of Energy Research, DOE, Bob Eisenstein, Assistant Director of Physical and Mathematical Science, NSF, and Christopher Llewellyn Smith, former Director-General of CERN at the Council session in December 1997. At the same occasion the USA was granted Observer Status at CERN.

  19. France at CERN

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Rolf Heuer, CERN Director General, visits the exhibition "La France au CERN". The exhibition France at CERN, organized by UBIFRANCE in collaboration with CERN's GS/SEM (Site Engineering and Management) service, took place from Monday 7 to Wednesday 9 June in the Main Building. The 36 French firms taking part came to present their products and technologies related to the Organization's activities. The next exhibition will be "Netherlands at CERN" in November.

  20. The CERN Library

    CERN Multimedia

    Hester, Alec G

    1968-01-01

    Any advanced research centre needs a good Library. It can be regarded as a piece of equipment as vital as any machine. At the present time, the CERN Library is undergoing a number of modifications to adjust it to the changing scale of CERN's activities and to the ever increasing flood of information. This article, by A.G. Hester, former Editor of CERN COURIER who now works in the Scientific Information Service, describes the purposes, methods and future of the CERN Library.