Section de physique Département de physique nucléaire et corpusculaire

Séminaires de physique corpusculaire Les séminaires du DPNC ont lieu les mercredis à 17.00 heures (chaques deux semaines) dans l'auditoire Stückelberg, Ecole de physique, 24, quai Ernest-Ansermet, Genève. Semestre d'Hiver 2002-2003 - Semestre d'Été 2003 - Semestre d'Hiver 2003-2004 - Semestre d'Hiver 2004-2005 - Semestre d'Été 2005 - Semestre d'Hiver 2005-2006 - Semestre d' Été 2006 - Semestre d'Hiver 2006-2007 - Semestre d'Été 2007 - Semestre d'Automne 2007 - Semestre de Printemps 2008 - Semestre d'Automne 2008 - Semestre de Printemps 2009 - Semestre d'Automne 2009 - Semestre de Printemps 2010 Séminaires des années précédentes - 1999-2000, 2000-2001, 2001-2002 Journées du DPNC - 24 juillet 2002 & 5 juillet 2004 & 14 septembre 2007 Retour DPNC

Semestre de Printemps 2010

Dr Hafeez Hoorani, Scientific Director, SESAME - Status of SESAME Project

Synchrotron-light for Experimental Science and Applications in Middle East SESAME is a project, which is established under auspices of UNESCO as intergovernmental organization with following members: Bahrain, Cyprus, Egypt, Iran, Israel, Jordan, Pakistan, Palestine Authority, and Turkey. The German Government as a gift has donated the injector and booster for SESAME after dismantling of BESSY in Berlin. The SESAME team will build the storage ring.

SESAME is a third generation light source with beam energy of 2.5 GeV, beam current of 400 mA, emittance 26 nm.rad and circumference of 133.2 m. It is under construction close to Amman – Jordan and will become operational end of 2012 or beginning of 2013. SESAME contains 16 straight sections out of which 13 straight sections are available for placing insertion devices such as undulator and wigglers.

An extensive scientific programme has been established with the help of Scientific Advisory Committee (SAC) and the Beamline Advisory Committee (BAC). From the beginning 7 beamlines are planned for Phase – I covering diverse areas of scientific interest such as: SAXS/WAXS, PX, IR, Soft X-ray, Powder Diffraction, XRF/XAFS and Atomic, Molecular spectroscopy (AMO) beamline. SESAME once operational will be a very competitive machine in the category of third generation light sources.

Dr Marc Schumann, Université de Zurich - Dark Matter and the XENON Experiment

There is convincing astrophysical and cosmological evidence that most of the matter in the Universe is dark: It is invisible in every band of the electromagnetic spectrum. Weakly interacting massive particles (WIMPs) are promising Dark Matter candidates that arise naturally in many theories beyond the Standard Model. Several experiments aim to directly detect WIMPs by measuring nuclear recoils from WIMPs scattered on target nuclei.

In this talk, I will give an overview on Dark Matter and direct Dark Matter detection. Then I will focus on the XENON100 experiment, a 2-phase liquid/gas time projection chamber (TPC) that is installed underground at the Gran Sasso Underground Lab (LNGS), and the future of the XENON project.

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Semestre d'Automne 2009

Dr Philippe Mermod, Université d'Oxford - Long-lived particle searches at colliders

The discovery of exotic long-lived particles would address a number of important questions in modern physics such as the origin and composition of dark matter and the unification of the fundamental forces. This talk will focus on searches for long-lived charged massive particles, where "charged" refers to the magnetic, electric or colour charge. Previous searches at the LEP and Tevatron Colliders allowed to put mass and cross section limits on various kinds of long-lived particles, such as Magnetic Monopoles and metastable leptons and up-type quarks. The new energy regime made available at the LHC will probe physics regions well beyond these limits. For instance, a new long-lived particle with mass 300 GeV carrying colour charge is expected to be copiously produced at the LHC and leave striking events in the detectors. I will outline a signature-based search strategy for long-lived massive hadrons in early ATLAS data.
Fichier .pdf de la présentation

Dr Ilias Efthymiopoulos, CERN - Highlights of the European Strategy Workshop for Future Neutrino Physics

Beginning of October 2009, a 3 day workshop was organized at CERN to consider the future neutrino physics with emphasis on the development work required for accelerator based neutrino physics. The high attendance and the quality of presentations and discussions made it a success also showing the dynamism and motivation of the European neutrino physicist community. The CERN workshop was an important step in a process where ongoing R&D projects and Design Studies in Europe were presented. At the same time it allowed scientific bodies, like the Panel on Future Neutrino Facilities established by the Scientific Policy Committee in December 2008 at the request of the CERN Council, to collect input and opinions of the European neutrino physics community in view of decisions to come. In the seminar selected highlights from the presentations and the summary discussions will be presented.

Dr Arno Straessner, Technische Universität, Dresden - The origin of mass

What is the origin of mass for elementary particles ? Since many years, this question motivates physicists to build large collider experiments. The most recent examples are the ATLAS and CMS detectors at the Large Hadron Collider at CERN. The currently well tested Standard Model predicts the existence of a new particle which has not yet been detected experimentally: the Higgs boson. It is the manifestation of the Higgs mechanism, which creates masses of elementary particles in a theoretically attractive way. The LHC experiments will search for the Standard Model Higgs boson, as well as for further Higgs bosons predicted by a super-symmetric extension of the model.

In the lecture, the general concept of mass in particle physics, as well as the relationship to macroscopic masses will be explained. After a short introduction to the physics of Higgs bosons, the experimental strategy of Higgs boson searches at the LHC will be presented. Eventually, perspectives for future activities, like the measurement of Higgs properties at the LHC and its successor, the super-LHC, will be given.

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Semestre de Printemps 2009

Dr Francesca Volpe MPIK, Max-Planck-Institute for Nuclear Physics, Heidelberg - Physics insights from recent HESS AGN observations

The extragalactic sources are still the most powerful, variable and brightest objects in the VHE gamma-ray sky. The improved sensitivity of the new generation of ground-based instruments have increased the VHE emitting population, providing information about cosmology and giving new clues about particle acceleration mechanisms at play in active galactic nuclei.

Emphasis will be put on the contribution of the H.E.S.S. experiment to the temporal variability of extragalactic gamma-ray sources, including an update on the most recent detections and on the giant flares from PKS 2155-304.

Dr Alison Lister, University of Genevar - What can we learn from top quark physics at CDF?

After a brief introduction to (or reminder of) the Tevatron accelerator and the CDF experiment, we will delve into the depths of how a top physics analyses is done at CDF. We will follow through how each of the pieces used to measure the top quark cross section are obtained or measured and finally how all the pieces are put together to get a measurement as precise as the current best theoretical predictions.
We can then use that analysis infrastructure to search for new physics that appears in the top event sample, in this particular case by describing a search for fourth generation top-like quarks, one of the few CDF analyses to see something "fishy" we don't fully understand.
This seminar will aim to illustrate more the process of carrying out a measurement at a hadron collider than of showing the whole array of top physics results from CDF. As a result of this, the talk will be targeted implicitly at younger scientists who have maybe not yet been able to see data, or anyone from outside accelerator-based experiments who is curious to know how we actually get to our results we show at conferences.

Prof. Gustaaf Brooijmans, Columbia University - Hunting for the Higgs with D0 at the Tevatron

The search for the Higgs boson is one of the most important endeavors in current experimental particle physics. At the eve of the LHC start, the Tevatron is delivering record luminosity allowing both CDF and D0 to explore a new region of possible Higgs masses. In this seminar, the techniques used to search for the Higgs boson at the Tevatron will be explained, limiting factors will be examined, and the sensitivity in the various channels will be reviewed. The newly excluded values of the standard model Higgs mass will be presented.

Dr. Pierre PUGNAT, CNRS - GHMFL (Grenoble High Magnetic Field Laboratory) - The OSQAR Experiments at CERN to probe QED & Astroparticle Physics from the Photon Interaction with a Magnetic Field

A collaboration between eight European Institutes and CERN is working on a new “2-in-1”, laser-based Particle Physics experiments for Optical Search of QED vacuum magnetic birefringence, Axions and photon Regeneration (OSQAR). Since its prediction in 1936 by Euler, Heisenberg and Weisskopf in the earlier development of the Quantum Electrodynamic (QED), the Vacuum Magnetic Birefringence (VMB) is still a challenge for optical metrology. Contributions to the VMB could also arise from new light scalar/pseudo-scalar particles like axions that couple to photons and this would manifest itself as a sizeable deviation from the pure QED prediction. On one side the interest in axion, providing the most plausible solution to the so-called strong-CP problem, lies beyond Particle Physics and overlaps with Cosmology since such particle is also considered as a serious dark matter candidate. On the other side, the domain of Physics that will be investigated is guaranteed by the QED, which aimed to be tested down to the 10^-22 level by measuring the relative difference of the vacuum refractive indices in a 9.5 T field. The measurement for the first time of this “vacuum anomaly” of the refraction index is in the same line than the measurement of the anomalous magnetic moment of the muon performed in the early years of CERN by G. Charpak et al. (1961). By re-using major achievements of the Large Hadron Collider (LHC), like superconducting dipoles and test infrastructure, OSQAR offers a unique opportunity to launch at CERN an innovative research programme in the emerging field of laser-based Particle/Astroparticle Physics. The status of the OSQAR project will be reported together with the theoretical background, first results (published in Phys. Rev. D 78, 092003, 2008) as well as short and long term perspectives.

Dr Mihail Chizhov, Physics Department, Sofia University, Bulgaria - Search for spin-1 excited bosons at the LHC

I will discuss the resonance production of new type spin-1 excited bosons, Z*, at hadron colliders. They can be observed as a Breit-Wigner resonance peak in the invariant dilepton mass distribution in the same way as the well-known hypothetical gauge bosons, Z'. This makes them very interesting objects for early searches with the LHC first data. Moreover, they have unique signatures in transverse momentum and angular distributions, which allow to distinguish them from other resonances.

Prof. Olaf Reimer, Stanford University - Observing the extreme universe with the Fermi Gamma-ray Space Telescope

The Fermi Gamma-ray Space Telescope (FGST, formerly GLAST) is an international observatory-type satellite mission with a physics program spanning from gamma-ray astronomy to particle astrophysics and cosmology. FGST was launched on June 11, 2008 and is successfully conducting science observations of the high-energy gamma-ray sky since August 2008. A varienty of discoveries has been made already, including monitoring rapid blazar variability, the existence of GeV gamma-ray bursts, and numerous new gamma-ray sources of different types, including those belonging to previously unknown gamma-ray source classes like msPSRs, globular cluster and non-blazar-type AGN. Fermi-LAT, the observatory's main instrument, also performed an accurate measurement of the diffuse gamma-radiation which clarifies the controversially discussed "GeV excess" reported by EGRET almost 10 years ago, detected of gamma-radiation from molecular clouds, proved that radio-quiet PSR constitute a substantial fraction among Galactic gamma-ray sources, and measured the cosmic GeV to TeV electron spectrum with high precision. An overview of the observatory status and already accomplished scientific results will be presented.

Dr Thierry Lasserre, CEA, Saclay - Status report on Double Chooz

The measurement of the last undetermined neutrino mixing angle theta-13 is the main goal of the next generation of neutrino oscillation experiments. The present limit is driven by the result of the Chooz experiment. Double Chooz is the next generation reactor experiment aiming to improve the current best sensitivity of the CHOOZ experiment by roughly one order of magnitude. The aimed sensitivity requires both the statistical and systematical errors to be significantly reduced with respect to past reactor experiments. In particular, the success of the project depends on the reduction of the systematics, made possible by the installation of a near identical detector and by the improvement of the detector design. The experimental concept will be presented in details. The first detector is now under construction since May 2008. The data taking is scheduled from end-2009. The second detector will be commissioned end in 2011.

Dr Fanny Dufour, DPNC, Université de Genève - Long baseline neutrino detectors for T2KK: Water Cherenkov versus
Liquid Argon

In this talk, I will present two proposals of long baseline neutrino experiments that are currently being investigated for the Tokai to Kamioka and Korea setup. The assumed neutrino beam is a 1.66 MW beam coming from the Tokai accelerator and providing 2.6 * 1021 protons on target per year. Two different detector technologies have been proposed to study this beam. Either water Cherenkov, or liquid Argon, I will present a comparison of the assumptions and expectations from these two proposals.
Fichier .pdf de la présentation

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Semestre d'Automne 2008-2009

Dr Gersende Prior, Lawrence Berkerley National Laboratory - The Sudbury Neutrino Observatory: probing the Sun from 2 km underground

The Sudbury Neutrino Observatory (SNO) experiment, located in a mine in Canada, started in 1999 and took solar-neutrino data for nearly seven years.

The experiment operated in three distinct phases reflecting different experimental configurations. Results from its first two phases have provided revolutionary insights on the neutrino properties and have verified our understanding of the energy production in the sun. The analysis of data from the final phase of the experiment, during which an array of special counters was deployed to enhance the measurement of solar neutrino flux, has been completed.

After an introduction on neutrinos and the SNO detector, I will discuss briefly the results from the first two phases and present in details the results of the third and final phase of the SNO experiment.

Dr Michel Sorel, IFIC (CSIC and University of Valencia) - Precision measurements of low-energy neutrino-nucleus interactions with the SciBooNE experiment at Fermilab

Do all modern accelerator-based neutrino experiments need to make use of kiloton-scale detectors and decade-long exposure times? In order to study the full pattern of neutrino mixing via neutrino oscillation experiments, the answer is probably yes, together with powerful proton sources. Still, to push the sensitivity of future neutrino oscillation searches into unchartered territory, those are necessary, but not sufficient, ingredients. In addition, accurate knowledge of neutrino interactions and neutrino production is mandatory. This knowledge can be acquired via small-scale and short-term dedicated neutrino experiments, such as SciBooNE. SciBooNE is a new neutrino experiment at Fermilab that has been designed to provide precision neutrino-nucleus cross-section measurements in the few-GeV neutrino energy range, where most future accelerator-based neutrino experiments are expected to operate. In this talk, a taste of ongoing analyses and preliminary results from SciBooNE will be given, together with their relevance for future neutrino oscillation studies.

Dr Filip Moortgat, ETH Zurich - Early searches for new physics at the CMS experiment

The CMS experiment at the LHC will provide unprecedented opportunities to discover new forms of matter and energy. This talk will first introduce the CMS experiment, its physics potential and general analysis strategy. It is followed by examples of possible searches for new phenomena in CMS, including Higgs, SUSY, and other exotic particles, with early LHC data.

Prof. Drew Baden, University of Marylan - Kinematics at Hadron CollidersExoplanets and quarks

I will review the kinematics of hadron collisions, especially relevant on the eve of the LHC startup. A variety of topics will be covered, meant to be useful for those not familiar with the origins and details of these considerations.

Dr Michela Prest, Universit`a degli Studi dell'Insubria, sede di Como - Bent crystals: a long story and its new frontiers

When a particle physicist hears the world “crystal”, he usually thinks of calorimeters, silicon detectors, a state of matter. When he hears the word “magnet”, he thinks of bulky, heavy objects. In 1976, E. H. Tsyganov experimentally demonstrated how a bent crystal 1 mm thick, a couple of mm wide and a few cm high can steer particles as a dipole of several tens of Tesla.
Crystals and the channeling phenomena have been studied for around 30 years. Hadron beam collimation has been immediately identified as their main application and the understanding of the physics of crystals and their experimental study have proceeded in parallel, discovering new phenomena and requiring new technological achievments.
This seminar describes the role of bent crystals in collimation in general and for the second phase of LHC in particular giving an insight of the physics of crystals. It will also revise the topic of radiation production by light particles in bent crystals which is still an open field both from the theoretical and experimental points of view and which would be a real breakthrough in several fields, from the production of positron sources for the Linear Collider to the generation of intense gamma beams for medical applications.

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Semestre de Printemps 2008

Dr Ties Behnke, DESY, FLC - The International Linear Collider: a global project for the future of particle physics

The International Linear Collider, ILC, is planned in a world-wide collaboration to be the next big collider after the LHC. The ILC will focus on precision - it will built upon the view of the Terascale physics which we will develop from the LHC results, and carry this further by adding precision measurements.

Over many years scientists have developed the foundation for the ILC proposal: a superconducting linear accelerator reaching energies between 500 GeV and 1 TeV. In parallel the requirements of unprecendented precision measurements has forced the experimental community to develop new detector concepts and event reconstruction techniques.

In this talk the state of the ILC project worldwide will be discussed, with a special focus on the planning of experiments for the ILC.

Prof. Michelangelo Ambrosio, INFN, Naple - Use of Multi-Walled Carbon Nanotubes for UV radiation detection

Optical and electrical properties of carbon nanotubes (CNT) have been widely investigated in the last years in view of their applications like: photo detection, solar cells, nano-electronics, opto-electronics, and so on. Sensitivity of Single-Walled CNT (SWCNT) to IR radiation has been demonstrated by different authors. Although the large interest in photo-sensitive properties of nanotubes, most of the work has been done on SWCNTs. The distribution of electronic states and electronic transitions is much more difficult to be predicted in MWCNTs than in SWCNTs. This makes, in fact, difficult any comparison between experimental work and theoretical predictions when Multi-Walled CNTs are used. However, interesting photocurrent properties have recently been observed also in samples containing Multi-Walled CNTs.

In this talk we report on measurements of CNT sensitivity to the radiation and on the realization and characterization of a prototype light detector based on MWCNTs. The results suggest that, despite the difficulty in modelling, the complex electronic structure of MWCNTs could be of advantage for the photosensitivity of CNTs-based devices by broadening the photo-response spectrum through the increasing of the possible electronic configurations and transitions.

Dr Michel Buenerd, Laboratoire de Physique Subatomique et de Cosmologie, Grenoble - CREAM, une expérience d'étude du rayonnement cosmique nucléaire à haute énergie entre 1 et 1000TeV

L'expérience CREAM (Cosmic Ray Energetics and Mass) a volé sous un ballon au-dessus du continent Antarctique en décembre-janvier derniers. L'exposé comprendra une présentation des objectifs du programme scientifique, une description générale de l'instrumentation, plus détaillée pour l'imageur Cherenkov, et une narration illustrée de la préparation du vol de CREAM en Antarctique, du lancement du ballon, du déroulement du vol avec quelques résultats en ligne, ainsi qu'une évocation de la vie à McMurdo.

Prof. Dr. Reiner Krücken, Technische Universität München - NuSTAR: Structue and Dynamics of exotic nuclei at FAIR

The Facility for antiproton and ion research (FAIR) will be constructed as an internation research facility in Darmstadt during the next 7 years. The research program covers a broad range of topics from the Physics of stored Antiprotons and highly charged atoms, plasma physics over exotic nuclei and nuclear astrophysics to hadron spectroscopy with antiprotons and the search for the triple point the QCD phase diagramm. In this talk the focus will be on the exciting opportunities to access nulcei far away from the valley of stability with a broad range of methods to study their structure and dynamics. Aside from our aim to understand the changes in shell structure and new modes of excitation of such exotic nuclei, these nuclei often play a role in the astrophysical processes of element synthesis. The talk will highlight the Nuclear Strucutre, Astrophysics, and Reactions (NuSTAR) facility and, using some examples, the major thrust of its physics program.

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Semestre d'Automne 2007-2008

Dr Phillip Urquijo, University of Melbourne - Precision determinations of |Vcb| and |Vub|

The success of the B factories has dramatically improved our understanding of CP violation. The search for clear signs of new physics through measurements of CP violation is limited by understanding of the CKM elements |Vub| and |Vcb|. Improvement of our knowledge of the least well known CKM parameter, |Vub|, therefore directly translates to a more stringent test of the Standard Model. The prodigious samples of B meson decays available at the B factories, along with advances in the theory involving semileptonic B decays, have been used to provide a determination of both, |Vcb| and the b-quark mass, with a precision of 1%, and bring the precision of |Vub| well below 10%.
The experimental and theoretical issues surrounding the determination of |Vub| and |Vcb| are complex and sometimes controversial. More recently, focus has been placed on ensuring accurate determinations of the b-quark mass using only semileptonic B decays, discarding the poorly understood radiative B decays.
The use of a variety of strategies for determining these CKM matrix elements provides important cross-checks on the theoretical uncertainties that in most cases dominate the overall uncertainties of |Vub| and |Vcb|. I will present various measurements of semileptonic B decays at Belle, and how they have meshed together to provide precision measurements of the CKM matrix element |Vcb|, the b-quark mass, and a better understanding of CKM matrix element |Vub|. I will also discuss important recent developments in the approach to the inclusive determination of |Vub|, which may have resolved the ~3 sigma discrepancy with measurements of the CP violation phases, and exclusive |Vub| determinations.

Dr Silvio Orsi, INFN Roma Tor Vergata- The first year in orbit of the PAMELA space experiment

The satellite-borne PAMELA experiment is designed to study charged particles in the cosmic radiation with a particular focus on antiparticles. PAMELA is mounted on the Resurs DK1 satellite that was launched from the Baikonur cosmodrome in Kazakhstan on June 15th 2006 and has a lifetime of at least 3 years. The PAMELA apparatus comprises a time-of-flight system, a magnetic spectrometer, a silicon-tungsten electromagnetic calorimeter, an anticoincidence system, a shower tail catcher scintillator and a neutron detector. PAMELA is performing indirect dark matter search through a detailed study of the positron and antiproton spectra (50MeV-270GeV and 80MeV-190GeV respectively). It also searches for antimatter (e.g. antiHe), studies the light nuclei component of the cosmic radiation, performs studies of cosmic ray propagation, of solar physics and solar modulation, and searches for local sources (through the study of the electron spectrum up to 2TeV). The talk will focus on the detector performances and on the preliminary results from the first year of operation.

Dr Patrick Huber, CERN - Neutrinos - where we stand and where to go

Neutrinos are enigmatic particles which have provided us with one of the clearest proofs for physics beyond the Standard Model of particle physics, so far. At the same time they are valuable probes of astro-physics and fundamental symmetries. The more we learn about the intrinsic properties of this particle the better we will be able to exploit its potential as a messenger of possibly exotic phenomena which otherwise would remain undetected. I will give a brief review of the current status of neutrino physics and introduce the open questions in the field. The emphasis in the second part of my talk will be on a tentative road map for addressing these questions with a focus on oscillation physics.

Prof. Adrian Biland, ETH, Zurich - Very High Energy Gamma-ray Astronomy with the MAGIC Telescope

Since the latest Cherenkov Telescopes started regular data-taking in 2004, the field of Very High Energy (VHE) Astronomy has drastically changed. The VHE sky is far richer than expected, and more than 50 sources have been found at energies above ~100 GeV. These sources belong to several classes of astronomical objects, e.g. Supernova Remnants, Plerions, X-ray Binaries as well as different classes of Active Galacic Nucleii (AGN). But many enigmatic VHE sources have no known counterpart, i.e. they are very bright above 100 GeV, while must be rather dim in other wavelengths.

The recent discovery of very fast VHE flux variations in AGNs indicate the potential to be able to test even most fundamental physics questions like effects predicted by some Quantum-Gravity models.

In my talk I will explain how Cherenkov telescopes work and show some selected results from MAGIC, the worlds largest Cherenkov telescope. Additionally, I will give a brief overview about the (near?) future plans for the next generation of VHE observatories.

Dr Klaus Kirch, PSI, Villigen - The electric dipole moment of the neutron

The electric dipole moment of the neutron (nEDM) has been searched for since the 1950s, improving the experimental sensitivity over the years by more than 6 orders of magnitude. A finite value of the nEDM would violate parity and time reversal symmetry and - invoking the CPT theorem - also CP. CP-violation, additional to the one known already, is needed in order to explain the observed baryon asymmetry of the universe. While in the electro-weak part of the Standard Model the nEDM is still another 6 orders of magnitude below the experimental limit, the strong interaction as well as, e.g. supersymmetric, extensions of the Standard Model foresee large CP-violation, and possibly lead to a finite nEDM. The nonobservation of the nEDM therefore lead to the " strong CP problem" and the "susy CP problem".

The progress to set up a new source of ultracold neutrons at PSI and the planned improved search for the nEDM at this source is described. As a byproduct, the first direct experimental limit on neutron -- mirror-neutron oscillations has been recently measured and will be reported.

Dr R. Smirnov-Rueda, Complutense University, Espagne - Manifest non-locality of bound electromagnetic fields in near zone of radiating sources: experimental observation

Standard relativistic locality (causality) is referred as impossibility of superluminal propagation. The creation of Quantum Mechanics (QM) led to Bell’s theorem which in the most general form sorted out QM predictions of strong correlations between space-like separated systems from probabilities of measurement outcomes calculated on the basis of local realism. EPR-type experiments gave support to QM predictions, casting doubts on standard locality. Since then common view has it that the quantum realm involves some type of misterious non-locality because it has no analogy in the classical worldview.
As response to the above-mentioned controversy on non-locality we propose a novel approach which concerns only classical relativistic field theory. We found that the actual experimental verification of the standard locality within domains of classical electromagnetism is essentially incomplete since it does not take into account the internal structure of EM field as a superposition of bound and radiation components. Any ideally rigorous test of EM field causality must be based on individual tests for both components so that our experimental procedure made a clear distinction between the near and the far zones where bound and radiation fields are dominant, respectively. Measurements were carried out in two different configurations between emitting and receiving antennas at 125 MHz (??2.5 m) clearly showing that the propagation rate of bound EM fields highly exceeds the velocity of light in the near zone but tends to c in far zone. It might indicate on a possible constraint on locality within transition from QM to classical phenomena.

Prof. Drew Baden, University of Marylan - Kinematics at Hadron CollidersExoplanets and quarks

I will review the kinematics of hadron collisions, especially relevant on the eve of the LHC startup. A variety of topics will be covered, meant to be useful for those not familiar with the origins and details of these considerations.

Prof. Phil Yock, University of Auckland - Exoplanets and quarks

The search for Earth-like extra-solar planets is one of the forefront areas of astronomy today. The NZ/Japan MOA collaboration uses the gravitational microlensing technique at high magnification. When the magnification exceeds 50, Earth-mass planets orbiting the lens star at distances ~ 2-3 AU are detectable. Twenty-eight events with magnification > 50 were found by MOA in 2007. These will be briefly reviewed, together with earlier events in which planets were detected, and one in which the shape of a star was measured.

The mathematics of gravitational microlensing is comparable to that of Rutherford scattering, which underpins current research in particle physics. Recent data from CERN on hadron production in ?-? interactions exceed the predictions of QCD by an order of magnitude at high pT. The amplitude for the process is asymptotically proportional to the sum of the squares of the charges of quarks. The data appear reminiscent of Rutherford’s old results, and suggestive of pre-QCD models where quarks had unit charges, or larger. Unequivocal tests could be made with the proposed International Linear Collider, but a plasma wakefield e-e- collider could provide the most affordable option.

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Semestre d'Été 2007

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Prof. Christoph Paus, MIT - Observation of Bs Mixing with the CDF Experiment

A long quest of about 20 years for the search of Bs Meson mixing has ended with the announcement of its observation in September 2006. The phenomenon of a particle changing into its own anti particle at a rate of about 3 trillion, in agreement with the Standard Model expectation, has been identified in a tour de force analysis at the CDF experiment.

Dr Aran Garcia-Bellido, University of Washington - Evidence for Production of Single Top Quarks at D0 and A First Direct Measurement of |Vtb|

Since 1995, top quarks have been observed in particle-antparticle pairs produced via the strong interaction at the Fermilab Tevatron ppbar collider. But top quarks can also be produced singly via the electroweak interaction. I will present evidence for the production of single top quarks in the DZERO data with an integrated luminosity of 0.9 fb-1. To isolate the signal from the large backgrounds, we have used three different multivariate analyses. I will discuss the results and their significance, and present the first direct measurement of the CKM matrix element |Vtb| > 0.68 at the 95% confidence level assuming standard model couplings. Fichier .pdf de la présentation

Dr Seven Bass, CERN/Innsbruck- Precision measurements in spin physics

The proton spin problem has been challenging experimentalists and theorists alike for the last 20 years. Polarized deep inelastic scattering experiments at CERN, DESY and SLAC have told us that quark partons contribute only about 30% of the proton's spin whereas relativistic quark models predict 60%. Where is the missing spin and why is the quark spin contribution so small ? In this talk I will give an overview of the proton spin problem and what it may be telling us about QCD, the vacuum and dynamical symmetry breaking. A precise measurement of neutrino-proton elastic scattering would make a vital contribution to resolving many of the outstanding issues.

Dr Antonio Limosani, KEK, Japon - Semileptonic and Radiative B-meson decays

The success of the B Factories at KEK and SLAC has furthered our knowledge of CP violation, a necessary ingredient for the creation of a matter-dominanted universe. Ever increasing data samples has ushered in a new era of precision CP measurements, in which the unitarity of the Cabibbo-Kobayashi-Maskawa matrix is examined for signs of New Physics. One of the crucial pieces of information, surprisingly, comes not from CP violation but from studies of semileptonic decays of the B mesons. I will discuss how various measurements of semileptonic and radiative B decays combine together to provide a precision measurement of the CKM matrix element |Vcb| and to determine the value of smallest CKM matrix element |Vub| and how such measurements depend upon progress in the theory of B decays.

Prof. Guido Drexlin, Karlsruhe Institute of Technology KIT - KATRIN - direct measurement of neutrino masses with sub-eV sensitivity

The major scientific objective of the international Karlsruhe Tritum Neutrino (KATRIN) Experiment is the model independent measurement of the electron neutrino mass in tritium beta decay with a sensitivity of 200 meV. In the cosmological context, this allows to investigate whether massive relic neutrinos left over from the Big Bang play a specific role as hot dark matter in the evolution of large scale structures of the universe. In particle physics KATRIN will allow to discriminate between different neutrino mass models (either of quasi-degenerate or hierarchical pattern).
The key components of KATRIN comprise an ultra-luminous windowless gaseous molecular tritium source, an electron transport and tritium elimination system, a tandem of electrostatic spectrometers with the tasks of energy pre-filtering and analysis (?E=1 eV) and a detector for ß-counting.
The talk gives an overview of the motivations for a next generation direct neutrino mass experiment as well as of the current project status. Special emphasis is put on the large main spectrometer with its diameter of 10 m and a length of 24 m, which is currently being commissioned on the site of Forschungszentrum Karlsruhe after an 8800 km voyage around Europe.
Finally the neutrino mass sensitvity of KATRIN is discussed and the implications of KATRIN for cosmology and particle physics are outlined.

Dr Saverio Braccini, Inselspital, University Hospital of Berne - Present and future of hadrontherapy

Hadrontherapy is a novel technique of cancer radiation therapy which employs beams of charged hadrons, protons and carbon ions in particular. Due to their physical and radiobiological properties, they allow to obtain a more conformal treatment with respect to photons used in conventional radiation therapy, sparing better the healthy tissues and allowing a better control of the disease. Hadrontherapy is the direct application of research in particle physics making use of specially conceived particle accelerators and detectors. Protons can be considered today a very important tool in clinical practice due to the several hospital-based centres in operation and to the continuously increasing number of proposed centres worldwide. Very promising results have been obtained with carbon ion beams in Germany and Japan and two hospital-based centres are now under construction in Europe. The present status of hadrontherapy is reviewed together with some innovative ideas issued form particle physics.

Dr Thomas Schietinger, PSI - Proposal to measure the muon electric dipole moment with a compact storage ring at PSI

In the Standard Model, lepton electric dipole moments (EDM) arise from the CP-violating phase in the CKM matrix at the three-loop level only, resulting in values that are many orders of magnitude below the sensitivity of current and future experiments. Lepton EDMs therefore offer an excellent opportunity to discover unambiguous evidence for new CP-violating phases, as called for by the baryon-antibaryon asymmetry of the universe. The muon EDM is one of the least constrained fundamental properties in elementary particle physics. We propose to utilize the large available flux of polarized muons at PSI to search for a muon EDM down to the level of $5 \times 10^{-23}\, e$ cm, about four orders of magnitude below the current limit. The experiment consists of a very compact storage ring (42 cm radius), in which a radial electric field compensates the g-2 precession, thereby greatly enhancing the sensitivity to a possible EDM-induced spin precession.

Dr Giles Gerbier, CEA/DAPNIA - À la recherche de la Matière Noire : état actuel et futur d'Edelweiss

Edelweiss est une expérience européenne, installée dans le Laboratoire Souterrain de Modane dans les Alpes, consacrée à la recherche de WIMP's, particules candidates pour expliquer la Matière Noire. Après un bref rappel sur la place grandissante qu'occupe cette question dans le contexte de la compréhension de notre univers, je donnerai les principes de fonctionnement des détecteurs cryogéniques en Germanium utilisés dans Edelweiss. Je présenterai ensuite les résultats obtenus dans la première étape Edelweiss I (phase 1 kg) et l'état actuel d'Edelweiss II (phase 9 kg), en période de validation et sa phase finale (30 kg). L'accent sera mis sur la compréhension des bruits de fond, les moyens de les éliminer et les prédictions de sensibilité dans les années à venir, en perspective avec les autres expériences concurrentes et les modèles de théorie supersymétrique. Le futur à long terme, en particulier le projet EURECA, sera évoqué.

Prof. A. Baldini, INFN, Pisa - A sensitive test of supersymmetric-GUT theories: the MEG experiment at PSI

The µ -> e gamma decay, which is absent in the Standard Model, is instead foreseen to occur in supersymmetric grand unified theories (SUSY-GUT) with a branching ratio which should be detectable by the MEG experiment. In this seminar the SUSY-GUT predictions for the µ -> e gamma decay rate and the connection with neutrino oscillations will be illustrated. The status of the MEG experiment will be described and the foreseen experimental sensitivity to the µ -> e gamma decay will be shown.

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Semestre d'Hiver 2006-2007

Dr Stefan Schoenert - Max-Planck-Institut fuer Kernphysik Heiderlberg - The Germanium Detector Array (GERDA) for the search of neutrinoless double beta decays of ⁷⁶Ge at LNGS line

The Germanium Detector Array (GERDA [1]) for the search of neutrinoless double beta decays of ⁷⁶Ge at LNGS will operate bare germanium diodes enriched in ⁷⁶Ge in an (optional active) cryogenic fluid shield to investigate neutrinoless double beta decay with a sensitivity of T_{1/2} > 2 x 10²⁶~years after an exposure of 100~rm kg x rm years. In this talk, I shall introduce the relevance of neutrinoless double beta decay, the experimental concepts of GERDA, the challenges and techniques to reduce backgrounds to neutrinoless double beta decay, and summarize the status of the project.

Dr Minh Quang TRAN - EPFL - ITER and the way toward a fusion reactor

Fusion is a possible source of electricity for base load, which is compatible with a sustainable development. The talk will first present the physics basis for the realisation of fusion and discuss the main aspects with respect to "fuel" resources, environment impact, safety and cost of electricity. The next generation of fusion devices ITER will produce 500 MW of (thermal) fusion power. The challenges of and R&D towards ITER will be outlined. The steps following ITER along the roadmap towards the first reactor producing electricity will be discussed, highlighting the major necessary development in material science and technology. Fichier .ppt de la présentation

Dr Carlos Gamez Pérez - Scientific Strategies in Anomalous Contexts : High Energy Physics in Spain and the Dictatorship of General Franco

Which is the perfect context for the rise and development of a scientific discipline? This is the most important question we try to answer when studying the case of High Energy Physics in Spain during the Dictatorship of General Franco. This communication analyses the relation between science and politics, the problem of tradition in science (concretely in physics), the relation between different scientific specialities like nuclear physics, the international influence on the Spanish community of Theoretical Physics and the political and scientific strategies made by the small Spanish community of High Energy Physics in order to succeed (at least partially) in growing into a scientific community.

In a methodological point of view, we can explain the difficulties in the construction of new historical sources in contemporary Physics by compiling documentation or making interviews or questionnaires.

Dr Michael MOLL, CERN - Radiation Tolerant Sensors for Solid State Tracking Detectors

The envisaged upgrade of the Large Hadron Collider (LHC) at CERN towards the Super-LHC (SLHC) with a 10 times increased luminosity of 1035 cm 2 s-1 will present severe challenges for the tracking detectors of the SLHC experiments. Unprecedented high radiation levels and track densities and a reduced bunch crossing time in the order of 10 ns as well as the need for cost effective detectors have called for an intensive R&D program. The CERN RD50 collaboration "Development of Radiation Hard Semiconductor Devices for Very High Luminosity Colliders" is working on the development of semiconductor sensors matching the requirements of the SLHC. Sensors based on defect engineered silicon like Czochralski, epitaxial and oxygen enriched silicon have been developed. With 3D, Semi-3D and thin detectors new detector concepts have been evaluated and a study on the use of standard and oxygen enriched p-type silicon detectors revealed a promising approach for radiation tolerant cost effective devices.
These and other most recent advancements of the RD50 collaboration, as well as an overview of the present understanding of the radiation induced microscopic processes leading to the deterioration of silicon detector properties, are presented and discussed. Fichier .pdf de la présentation.

Prof. Olivier Martineau-Huynh, LPNHEP, IN2P3, France - Astronomie gamma avec H.E.S.S.

L’expérience H.E.S.S. (High Energy Sterescopic System) est en train de marquer le domaine de l’astronomie gamma. Composée de quatre télescopes à effet Cerenkov installés en Namibie, elle a en effet permis la découverte en 3 ans de plus de 20 nouveaux émetteurs de rayonnement électromagnétique multi-TeV, alors qu’une dizaine seulement avaient été découverts au cours des deux décennies précédentes. Après une rapide présentation des sources possibles de rayonnement gamma au TeV, j’expliquerai le principe de détection des télescopes Cerenkov puis détaillerai les résultats les plus marquants obtenus par H.E.S.S. au cours des trois dernières années. Je présenterai certains des objets étudiés par H.E.S.S. (par exemple la première source périodique au TeV, ou la galaxie radio M87), et soulignerai l’apport de H.E.S.S. à notre connaissance des rayons cosmiques et à la cosmologie. Fichier .pdf de la présentation

Prof Erwin Flueckiger, Université de Berne - Solar Flares

Solar flares are generally defined as "rapid releases of energy from a localized region on the Sun in the form of electromagnetic radiation, energetic particles, and mass motions". Although the first record of a solar flare in the scientific literature dates back to 1859, the physical processes involved in these high-energy phenomena are still far from being fully understood. Significant progress, however, has been achieved in the understanding of the scenarios of gradual and impulsive flares, their relation to coronal mass ejections, and the acceleration of particles up to relativistic energies. Using recent examples like the January 20, 2005 event, characteristic signatures of solar flares at the Sun, in interplanetary space, and at the Earth, are reviewed, and the significance of different observational techniques is addressed.

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Semestre d'Été 2006

Prof. Nicolas Prantzos, CNRS, Paris - Gamma-ray line astronomy

Gamma-ray lines from cosmic sources provide unique isotopic information, since they originate from energy level transitions in the atomic nucleus. Gamma-ray telescopes explored this astronomical window in the past three decades, detecting radioactive isotopes that have been ejected in interstellar space by cosmic nucleosynthesis events. Astronomical gamma-ray telescopes feature standard detectors of nuclear physics, but have to be surrounded by effective shields against local instrumental background, and need special detector and/or mask arrangements to collect imaging information. Due to exceptionally-low signal/noise ratios, progress in the field has been slow compared with other wavelengths. Despite the difficulties, this young field of astronomy is well established now, in particular due to advances made by NASA's Compton Gamma-Ray Observatory in the 90ies. The most important achievements on extra-solar gamma-ray lines so far concern: short-lived radioactivities that have been detected in a couple of supernovae (56Co and 57Co in SN1987A, 44Ti in Cas-A), the diffuse glow of long-lived 26Al and 60Fe that that has been mapped along the entire plane of the Galaxy, and last but not least, positron annihilation that has been observed in the inner Galaxy since the 70ies. I will review past and future developments in the field, in the light of recent results from ESA's INTEGRAL satellite, which is in operation since early 2003.

Prof. Ugo Gastaldi, Laboratori Nazionali di Legnaro, Italy - PVLAS, an experiment to probe vacuum with polarized light: results and prospects

The PVLAS experiment operates at LNL an ellipsometer (with a 6m long vertical Fabry-Perot cavity which embraces a rotating 5.5 Tesla superconducting dipole magnet) that can measure ellipticity and rotation induced by the magnetic field onto linearly polarized laser light. The sensitivity of the instrument is of the order of 10^-7rad sqrtHz^-1 with infrared light stored in the Fabry-Perot. Measurements have been made with infrared laser light until 2004, and with green light during 2005. With a residual pressure less than 10^-7mbar the apparatus gives both ellipticity and rotation signals at the 10^-7rad level. These signals can be interpreted as being generated largely by vacuum ellipticity and dichroism induced by the transverse magnetic field. If this interpretation is correct, a tool has become available to characterize physical properties of vacuum as if it were an ordinary transparent medium. A microscopic effect responsible for the induced dichroism could be the existence of ultralight spin zero bosons with masses of the order of 10^-3 eV, that would couple to two photons and would be created in the experiment by interactions of photons of the laser beam with virtual photons of the magnetic field. The coupling gm?? of these bosons to two photons would be of the order of 10^-6 GeV . Axions and dilatons are respectively pseudoscalar and scalar bosons that could exist with masses of the order of 10^-3 eV and with extremely weak couplings to ordinary matter.

Prof. Claus Rolfs, Ruhr Universität Bochum, Germany - Fusion reactions in stars

Fusion reactions play a key role in stars for the understanding of their energy production, evolution and neutrino emission. The experimental approaches in the study of some key reactions are presented. An important aspect are hereby the effects of electron screening, which increase the fusion cross sections. The fusion reaction d(d,p)t was recently studied in deuterated metals and insulators, i.e. for 58 samples across the periodic table, where a dramatic increase was observed for the metals. An explanation of the data is presented and possible future applications are discussed.

Prof. Valery Nesvizhevsky, Institut Laue-Langevin de Grenoble - The project GRANIT to measure the resonance transitions between the gravitationally bound quantum states of neutrons

The gravitationally bound quantum states of matter were observed for the first time due to unique properties of ultracold neutrons. Some parameters of the lowest quantum states of neutrons were measured in recent experiments in so-called integral and differential measuring modes. We are going to improve considerably the accuracy of these experiments using resonance transitions between the gravitationally bound quantum states of neutrons. In addition to the obvious interest to study this phenomenon itself, this experiment could be useful for different fields of physics such as, for instance, the search for spin-independent or spin-dependent short-range fundamental forces, the quantum-mechanical localization or the loss of quantum coherence. We will discuss different methodical approaches to measure the resonance transitions and the challeges and constrains in such an experiment.

Andrée Robichaud-Véronneau, Université de Genève - ZEUS: A detector for HERA

HERA is the first lepton-proton collider in the world where a center of mass energy of 318 GeV is reached. Since 1992, the ZEUS detector is gating luminosity from it to probe QCD and look for exotic phenomena of fundamental particle physics. A history and overview of the detector and collider will be presented as well as important physics contributions made by the ZEUS experiment to the understanding of our world.

Dr Albert De Roeck, CERN - CMS Physics Performance

An overview will be given of the physics capabilities of the CMS detector at the LHC. CMS is now completing its Physics Technical Design reports, summarizing the expected detector performance in a first volume and the physics reach with up to 30 fb-1 in the second volume. Results on the performance of the CMS detector as obtained from detailed simulations are presented for realistic operating conditions, and validated where possible against test beam and cosmic ray data. Procedures to measure the performance from early LHC data wil be described. Finally, a selected number of results from new physics studies will be presented.

Dr. David Lhuillier, CEA, Saclay - Violation de parité en diffusion Moller et tests précis du modèle standard à basse énergie

Les mesures du courant faible neutre à basse énergie, loin du pôle du Z⁰, permettent de tester le secteur électrofaible du modèle standard d’une manière complémentaire aux collisionneurs de haute énergie. La très faible intensité du courant neutre aux cinématiques étudiées est compensée par une très grande précision de mesure qui permet de tester indirectement l’existence d’une nouvelle physique jusqu’à l’échelle du TeV.
L’essentiel de l’exposé sera consacré à la présentation de l’expérience E158 qui isole la contribution du courant faible dans la diffusion Møller (e^-e^- -> e^-e^-) par l’intermédiaire de la violation de parité dans ce processus. L’impulsion transférée lors de la réaction est trois ordres de grandeur plus petite que la masse du Z⁰ et la violation de parité se traduit par une asymétrie de taux de comptage de l’ordre de 10^-7, mesurée à 10^-8 près. Une telle précision est rendue possible par les récents développements technologiques des sources d’électrons polarisés.
Le résultat de E158 sera présenté dans le contexte des autres mesures publiées (violation de parité dans les atomes et diffusion de neutrinos) et je discuterai son impact sur l’existence de quelques scénarii de nouvelle physique.
La fin de l’exposé sera consacrée aux perspectives d’expériences de violation de parité ouvertes par l’amélioration constante de la précision de mesure des asymétries.

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Semestre d'Hiver 2005-2006

Dr Mathieu Ribordy, Université de Mons-Hainaut, Belgique - Astronomie neutrino au Pôle Sud

Nous allons discuter du détecteur AMANDA enterré dans les profondeurs du Pôle Sud et de résultats récents obtenus dans la recherche de sources astrophysiques de neutrinos de haute énergie. Les limites actuelles au flux diffus, de plus en plus contraignantes, sont proches de la limite supérieure de Waxman-Bahcall. La sensibilité à la recherche de sources ponctuelles a atteint le niveau requis pour détecter des objets tels que Mrk501, en supposant un flux de neutrinos d'intensité comparable au flux de gamma, au-delà de ~1 TeV. Le successeur de AMANDA est le télescope IceCube dont le déploiement a commencé cette année. Il occupera à terme un volume de 1km³ et mènera à un gain de sensibilité de près de deux ordres de grandeurs. Aussi, des opportunités pour tester de la nouvelle physique s'offriront: entre autres, la recherche de matière obscure ou la mise en évidence de nouvelles sources d'oscillations de neutrinos par l'exploitation de l'incomparable statistique de neutrinos atmosphériques de haute énergie. fichier .pdf de la présentation

Prof. Peter Weilhammer, Université et INFN Perugia - CVD Diamond Radiation Sensors For Application In Very High Radiation Environments

After an introduction into the basic properties and operating principles of CVD diamond radiation sensor material, measurements of charge carrier collection and leakage currents in single crystal and polycrystalline CVD diamonds will be presented. Results from measurements of the effective mobilities and carrier lifetime of electrons and holes, using the Transient Current Technique (TCT), will be shown. Radiation hardness of CVD polycrystalline diamonds will be discussed. A summary of radiation hardness measurements, carried out over several years, will be presented for polycrystalline material. Performance of diamond tracking detectors will be discussed. Preliminary results from tests on a full ATLAS pixel module, equipped with 16 radiation hard readout chips, will be shown. Finally present and future application of diamond detectors in beam monitoring and diagnostics at different accelerators are discussed. fichier .pdf de la présentation

Prof. Sonia Kabana, University of Nantes and Subatech, France - The search for the QCD phase transition

We review the experimental efforts to reproduce and measure in the laboratory the QCD phase transition from deconfined quarks and gluons to hadrons, colliding heavy ions for example gold on gold, at energies high enough to cross the critical energy density of about 1 GeV/fm3, predicted by lattice QCD.

We will discuss our present understanding of the results acquired at BNL AGS, CERN SPS, and recently at BNL RHIC. In particular we will address the 'discovery of a new state of matter..' announced at CERN (2000) and at RHIC (2005), as well as the open questions reflecting into new experiments at the CERN LHC and at the GSI FAIR.

Dr Luis Mario Fraile, CERN - Highlights from the ISOLDE facility

The ISOLDE online mass separator located at CERN provides a wide variety of radioactive ion beams for research on nuclear physics, nuclear astrophysics, fundamental interactions, condensed matter and others fields. The facility maintains an extensive physics-driven target and ion source development programme, which has helped ISOLDE keep its international status throughout decades. The low-energy programme is complemented by research performed with accelerated radioactive ion beams. This has been made possible by the REX-ISOLDE post-accelerator, which has opened up new fields of study by means of transfer reactions and Coulomb excitation of exotic nuclei.

ISOLDE is integrated in the European research structure through the EURONS (EUROpean Nuclear Structure) infrastructure initiative, and plays a key role in the design study of the future European third-generation ISOL radioactive ion beam facility, EURISOL. In this context, the presentation will highlight recent ISOLDE scientific achievements and technical developments together with an outlook to future upgrades. fichier .pdf de la présentation

Prof. Krzysztof Piotrzkowski, Université Catholique de Louvain, Belgique - High energy photon interactions at the LHC

A significant fraction of proton collisions at the LHC will involve photon interactions at the energies above the electroweak scale. Experimental prospects for studying such interactions at the LHC will be presented, including the rôle of the forward proton detectors in tagging and reconstruction of photon induced events. Physics scope of high-energy photon-photon fusion and photon-proton interactions at the LHC will be discussed, focusing in particular on the two-photon production of W and Z pairs, and the associated photo-production of W and Higgs bosons. Finally, importance of studying the exclusive production of lepton pairs for searches beyond the Standard Model and for calibrating detectors will be addressed.

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Semestre d'Été 2005

The BooNE experiment sets out to definitively explore the neutrino oscillation signal reported by the Los Alamos LSND experiment. MiniBooNE represents the first phase for the BooNE collaboration and consists of a 1 GeV neutrino beam and a single, 800-ton mineral oil detector (the MiniBooNE detector). The MiniBooNE detector is located 500 meters downstream of the neutrino source, and is optimized to search for the LSND signal.

In 1995, the LSND collaboration presented strong evidence for the oscillation of muon anti-neutrinos to electron anti-neutrinos. These results lead to mass-squared differences around 1 eV^(2) - much larger than those observed by atmospheric and solar neutrino experiments.

The LSND measurement remains to be confirmed. If BooNE confirms this signal, then significant changes are demanded of our current model for understanding the building blocks of nature. In particular, a BooNE oscillation result will tell us that nature contains at least four different types of neutrinos, at least one of which would be almost totally non-interacting (or sterile).

Prof. Paul TIPTON, University of Rochester (New-York) - Looking for new physics around the Top

In Run 1 of Fermilab's Tevatron p-pbar collider, a slight excess of dilepton top candidates were observed. In addition some of these events had kinematic features that were not expected in Standard Model (SM) top decays. Using Run II data from the upgraded CDF detector, we have examined a larger sample of dilepton events for evidence of non-SM physics. Among the studies is an a priori defined search for anomalous kinematics.

Prof. Oliver Bruning, CERN - Accelerator Physics Challenges for the Large Hadron Collider at CERN

The Large Hadron Collider project at CERN will bring the energy frontier of high energy particle physics back to Europe and with it push the accelerator technology into uncharted teritory. The talk presents the LHC project in the context of the past CERN accelerator developments and addresses the main challenges in terms of technology and accelerator physics. .pdf

Prof. Ulrich Straumann, Université de Zurich - Status and prospects of the LHCb experiment

The LHCb experiment is designed to exploit the large b quark production cross section in pp collisions at the future LHC at CERN in order to perform a wide range of precision studies of CP violating phenomena and rare decays in the B meson systems. The experiment will operate at a moderate luminosity of 2Ã^×1032 cm-2s-1 and should be fully operational from the start of LHC operation in mid of 2007. An overview of the design and present production status of the experiment will be given, with some emphasis on the silicon tracking system, provided by the Swiss groups. The physics reach of the experiment will be demonstrated by the results of some Monte Carlo simulations.

Prof. Edoardo Charbon, EPFL - CMOS Single Photon Detectors

With the integration of Single Photon Avalanche Diodes (SPADs) in conventional CMOS technology, the design of scalable single photon imagers has become possible. SPAD pixels exhibit high sensitivity, dynamic range and low jitter, thus enabling new as well as conventional applications. Moreover, due to the digital nature of SPAD detectors, the imager architecture may be significantly simplified with the elimination of traditional components such as amplifiers, S/Hs, and ADCs as well as complex readout schemes and 1/f or FPN suppression techniques.

As an illustration of the potential of SPADs, a 3D imager is presented capable of capturing the depth map of an arbitrary scene. Depth is measured by computing the time-of-flight of a ray of light as it leaves the source and is reflected by the objects in the scene. The round-trip time is converted to digital code independently for each pixel using a CMOS time-to-digital converter. To reach millimetric accuracies an array of 32x32 SPADs is used. The scene is illuminated using a cone of low power pulsed laser light, thus no mechanical scanning devices or expensive optical equipment are required. .pdf

Prof. Alexandre Refregier, CEA, Saclay - Weak lensing et énergie sombre

L'effet de cisaillement gravitationnel faible, ou "weak lensing", permet de cartographier directement la distribution de la matière sombre dans l'univers. Cette distribution peut être comparée aux prédictions des modèles de formation des structures afin de contraindre les paramètres cosmologiques. Après un rappel des principes du weak lensing, je résumerai le statut observationnel de ce domaine en évolution très rapide. Je présenterai ensuite les perspectives offertes par les futurs relèves grands champs. En particulier, je montrerai comment ces nouvelles mesures du weak lensing par les grandes structures permettront de placer des contraintes fortes sur l'énergie sombre, en complément d'autres sondes telles que le CMB et les supernovae. Je montrerai enfin les perspectives offertes par DUNE, une future mission spatiale grands champs, pour la cosmologie.

Prof. Michele Maggiore, Université de Genève - The search for gravitational waves. Physical motivations and experimental perspectives

Professor Maggiore will give an overview of gravitational-wave physics, addressing two main questions:
1) What are the physical motivations for gravitational-wave research, both from the point of view of astrophysics and of high-energy physics.
2) Present staus and future perspectives of gravitational-wave experiments.

Prof. Jean-Pierre Lees, LAPP, Annecy - Recent results of the BaBar experiment on CP Violation in the B mesons decays

After a brief introduction on B physics at B factories and the current status of the BaBar experiment, I will show how CP violation effects in the decays B->D(*)K(*) and B->D(*)pi/rho can be used to probe the value of the angle gamma of the Unitarity triangle, and what precision can be expected on this measurement by the end of the BaBar running, in 2008.

Semestre d'hiver 2004-2005

Semestre d'hiver 2004-2005

A review of the current experimental situation will be given with emphasis on recent results obtained at CERN. The speaker will argue that the availability of high energy kaon beams at CERN allows one to make incisive tests of the Standard Model. In particular the NA48 Collaboration has studied the possibility to measure the reaction K+-->pi+ nu nubar leading to a ~10% precision on the knowledge of the |Vtd| CKM parameter. Prospects to study of the CP-Violating decays KL--> pi0 e+e- (mu+mu-) and KL--> pi0 nu nubar will also be briefly described.

Prof. Jean-Pierre Delahaye, CERN - The CLIC study of Multi-TeV e⁺/e^- Linear Collider

After a brief description of a CLIC scheme to extend Linear Colliders into the Multi-TeV colliding beam energy range, the main challenges and the very promising results already achieved will be presented. The presentation will mainly focus on the Test Facility (CTF3) presently under construction at CERN within a broad collaboration to address the main key issues and demonstrate the feasibility of the CLIC technology before 2010. .pdf

Prof. Zbigniew Was, Institute of Nuclear Physics, Cracow, Poland - Tau leptons as window for new physics at accelerator experiments

Because of its mass and relative clean experimental signature, the tau lepton is expected to play an important role in the phenomenology of future experiments. We will present the use of observables using taus for the following applications. Higgs boson parity measurement at ILC, signatures for Higgs discovery scenarios at LHC and for the measurement of CP properties of scalar B⁰ decay to tau tau (if discovered) at Belle/BaBar. This wide spectrum of experimental applications will be complemented with a presentation of the essential theoretical and technical aspects of these projects.

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Semestre d'été 2002-2003

Prof. R. Klanner- DESY,U.Hamburg: New results from HERA and DESY

Prof. J.J. Gómez-Cadenas - U.Geneva,U.Valencia: From Harp to JHF. A neutrino road

Dr. U. Langenegger - SLAC: Semileptonic B Decays at BABAR

Dr. J. Carbonell - ISN Grenoble: Petits noyaux, gros problèmes ...

Au cours de la dernière décennie ont été obtenus un certain nombre de potentiels nucléon-nucléon d'une très grande précision. Ils sont l'aboutissement d'une longue série de travaux dans leurs sagas respectives (Nijmegen, Argonne, Bonn, \ldots) et atteignent pratiquement un chi^2/datum=1.

Par ailleurs le développement des moyens et des méthodes de calcul a permis l'obtention des solutions exactes -- au sens numérique -- de l'équation de Schrodinger pour les noyaux à petit nombre de nucléons. Si, en ce qui concerne les réactions nucléaires, ce nombre ne dépasse pas à l'heure actuelle A=4, on est en mesure par des méthodes de Montecarlo d'obtenir les énergies de liaison jusqu'à A=10. Les succès de cette démarche ab initio ont fait émerger de sérieuses difficultés pour notre compréhension du noyau. D'une part il n'est plus possible de penser un noyau comme un ensemble de nucléons interagissant par le potentiel NN. D'autre part l'interaction résiduelle -- forces à trois et quatre corps -- est mal connue et doit être ajustée chaque fois que l'on avance dans la complexité. En outre elle ne semble pas en mesure de décrire les résonances dès A=4.

Nous passerons en revue les derniers résultats concernant les noyaux légers et nous discuterons la possible existence de petits clusters liés de neutrons (N>=3) ainsi qu'il a été suggéré lors d'une récente expérience faite au GANIL. .ps

Dr. B. Lott - CEN Bordeaux: L' exploration du ciel en rayons gamma de haute énergie avec  GLAST

Dr. E. Lorenz - MPI, Munich: Ground-based Gamma Ray Astronomy, Status and Perspectives

Dr. María Teresa Dova - Universidad Nacional de La Plata, Argentina: The Pierre Auger Observatory: Status, performance and perspectives

Prof. Dr. Ludwig Tauscher - University of Basel: The DIRAC experiment and the pion-pion scattering length

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Semestre d'hiver 2002-2003

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Semestre d'hiver 2002-2003

Prof. W. de Boer - U. Karlsruhe: Supersymmetry in Particle Physics and Cosmology

Prof. M. Cerdonio - INFN Padova: The search for gravitational waves

It is commonly accepted that the "observatory phase" will start after a substantial upgrade of the present detectors. ?Dual? resonators are under study to get wideband best sensitivities in kHz frequency range. Design studies are in prograss for an "advanced" LIGO2 in US and for a 4km, cryogenic mirrors, interferometer in Japan. In a shared effort, ESA and NASA will fly, in the 2011 timeframe, LISA, a 5million km Interferometer in space, which will detect gw in the mHz frequency range, as from supermassive galactic center black-holes.

Dr. M.H. Schune - LAL Orsay: Les oscillations B⁰ \barB⁰

Dr. John Field - Université de Genève: La Mécanique Quantique dans l'Espace-Temps et les Oscillations de Neutrinos

Dr. Rolf Landua - CERN: Status and Future of Antihydrogen Physics

Last updated: 28 October 2003, Blanchard Catherine