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The central focus of the research is on conducting a societal metabolism approach to the region of Pays de la Loire in France. For doing so, the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) methodology is used where fund variables such as human activity and land use are correlated over flow variables, such as energy and gross added value following the theoretical framework of Georgescu-Roegen [1]. Thereafter the feasibility, viability and desirability of current development patterns for the region are questioned to be able to transition into alternative scenarios. [ABSTRACT FROM AUTHOR]

We have discussed single and central diffractive production of cc pairs in the Ingelman-Schlein model. In these calculations we have included diffractive parton distributions obtained by the H1 collaboration at HERA and absorption effects neglected in some early calculations in the literature. The absorption effects which are responsible for the naive Regge factorization breaking cause that the cross section for diffractive processes is much smaller than that for the fully inclusive case, but could be measured at RHIC and LHC by imposing special condition on rapidity gaps. We discuss also different approaches to diffractive production of heavy quark/antiquark [1, 2, 3]. The particular mechanism is similar to the diffractive dissociation of virtual photons into quarks, which drives diffractive deep inelastic production of charm in the low-mass diffraction, or large β-region. [ABSTRACT FROM AUTHOR]

In the framework of the kT-factorization approach, the production of prompt photons in association with a heavy (charm or beauty) quarks at high energies is studied. The consideration is based on the O(αα2s) off-shell amplitudes of gluon-gluon fusion and quark-(anti)quark interaction subprocesses. The unintegrated parton densities in a proton are determined using the Kimber-Martin-Ryskin prescription. Our numerical predictions are compared with the D0 and CDF experimental data. Also we extend our results to LHC energies. [ABSTRACT FROM AUTHOR]

We report on charm production at LHC. The production of single cc pairs is calculated in the kt-factorization approachwith different unintegrated gluon distributions. Examples of transverse momentum distributions for charmed mesons are presented and compared to recent experimental results from LHC. Some missing strength is observed for most of UGDFs. Furthermore we discuss production of two cc pairs within double-parton scattering (DPS) and single-parton scattering (SPS) mechanisms. Surprisingly large cross sections, comparable to single cc pair production are predicted. We discuss first experimental results from LHCb collaboration on production of pairs of D mesons of the same flavour. [ABSTRACT FROM AUTHOR]

We report on recent calculations of low missing mass single (SD) and double (DD) diffractive dissociation at LHC energies. The calculations are based on a dual-Regge model, dominated by a single Pomeron exchange. The diffractively excited states lie on the nucleon trajectory N*, appended by the isolated Roper resonance. Detailed predictions for the squared momentum transfer and missing mass dependence of the differential and integrated single-and double diffraction dissociation in the kinematical range of present and future LHC measurements are given. [ABSTRACT FROM AUTHOR]

We review our pre-LHC predictions of the total, elastic, total-inelastic, and diffractive components of proton-proton cross sections at high energies, expressed in the form of unitarized expressions based on a special parton-model approach to diffraction employing inclusive proton parton distribution functions and QCD color factors and compare with recent LHC results. [ABSTRACT FROM AUTHOR]

The French research on cosmic rays in the first half of the 20th century is summarized. The main experiments are described as the discovery of air cosmic ray showers by Pierre Auger. The results obtained at the French altitude laboratories like the 'Pic du Midi de Bigorre' are also briefly presented. [ABSTRACT FROM AUTHOR]

In the framework of the French R&D program for the Generation IV reactors and specifically for the sodium cooled fast reactors (SFR), studies are carried out on innovative instrumentation methods in order to improve safety and to simplify the monitoring of fundamental physical parameters during reactor operation. The aim of the present work is to develop an acoustic thermometry method to follow up the sodium temperature at the outlet of subassemblies. The medium is a turbulent flow of liquid sodium at 550 °C with temperature inhomogeneities. To understand the effect of disturbance created by this medium, numerical simulations are proposed. A ray tracing code has been developed with Matlab© in order to predict acoustic paths in this medium. This complex medium is accurately described by thermal-hydraulic data which are issued from a simulation of a real experiment in Japan. The analysis of these results allows understanding the effects of medium inhomogeneities on the further thermometric acoustic measurement. [ABSTRACT FROM AUTHOR]

Diphoton events at the LHC can provide clean signals of heavy neutral quantum states predicted by New Physics models. These non-standard particles would manifest themselves by s-channel peaks in inclusive distributions in the diphoton invariant mass. Once discovered, the quantum numbers of such a diphoton resonance need to be determined in order to identify the associated non-standard physics, in the first place the spin by an angular analysis of the events. We here discuss this problem by comparing, as competing sources of a diphoton resonance, the spin-2 Randall-Sundrum graviton excitation and a spin-0 scalar exchange, by means of a specific angular-integrated asymmetry predicted theoretically at next-to-leading order in QCD. For the LHC with nominal energy of 14 TeV and integrated luminosity 100 fb-1, we find that graviton exchange could be discriminated against the scalar one with same mass MR and events rate, up to MR≃3.2TeV. [ABSTRACT FROM AUTHOR]

The Inner Tracking System of the ALICE experiment plays a crucial role in heavy flavour production measurements at central rapidity in Pb-Pb collisions thanks to its precise tracking and vertexing capabilities in a high-multiplicity environment. In view of the future luminosity increase at LHC, the ALICE experiment is developing an upgrade startegy where a new, more performant ITS is being proposed. Improving the tracking and particle identification performances, the resolution on the secondary vertices in the low momentum region as well as the read-out capabilities, the ITS will make new important measurements in the charm and beauty sector accessible in central heavy-ion collisions: the Λc baryon, B mesons and the total charm production cross section. In these proceeedings both the performances of a new ITS and some new accessible measurements of the heavy flavour physics in ALICE will be discussed. [ABSTRACT FROM AUTHOR]

We report on recent investigations of the underlying event in pp collisions at the LHC. The underlying event activity has been studied in Drell-Yan processes, using the jet area method and at forward rapidity. Strangeness production in the underlying event has been measured. [ABSTRACT FROM AUTHOR]

We discuss the case of the diffractive Higgs production at LHC. Aim of this talk is to propose the method of using Fracture Functions as an alternative to the ones already present in the literature. We discuss some of the questions involved and the main related issues. [ABSTRACT FROM AUTHOR]

We discuss the theoretical and experimental details of two of the main results obtained by LHCb with the 2011 data, namely the measurement of the mixing-induced CP-violation in the decay Bs0→J/ψ[lowercase_phi_synonym] and the upper limits on the decays B(s)0→μ+μ-. Then we describe the possible strategies to obtain new constraints on two different New Physics models in the light of these results. [ABSTRACT FROM AUTHOR]

In this Sixth International School on Field Theory and Gravitation, I was invited to give this talk to the students and researchers of Field Theory mainly about LHC - The Large Hadron Collider and results. I will try to summarize the main daily life of the high energy physics and give an idea about the experiments and the expectations for the near future. I will comment the present results and the prospects to LHC/CMS. [ABSTRACT FROM AUTHOR]

Conventional SO(10) models involve more than one scale for a complete breaking of the GUT symmetry requiring further assumptions on the VEVs of the Higgs fields that enter in the breaking to achieve viable models. Recent works where the breaking can be accomplished at one scale are discussed. These include models with just a pair of [formula] of Higgs fields. Further extensions of this idea utilizing [formula] of Higgs representations allow both the breaking at one scale, as well as accomplish a natural doublet-triplet splitting via the missing partner mechanism. More generally, we discuss the connection of high scale models to low energy physics in the context of supergravity grand unification. Here we discuss a natural solution to the little hierarchy problem and also discuss the implications of the LHC data for supersymmetry. It is shown that the LHC data implies that most of the parameter space of supergravity models consistent with the data lie on the Hyperbolic Branch of radiative breaking of the electroweak symmetry and more specifically on the Focal Surface of the Hyperbolic Branch. A discussion is also given of the implications of recent LHC data on the Higgs boson mass for the discovery of supersymmetry and for the search for dark matter. [ABSTRACT FROM AUTHOR]

We employ third family Yukawa unification, predicted by simple supersymmetric SO(10) models, to estimate the lightest MSSM Higgs boson mass. For μ > 0 (or μ < 0) and mt = 173.1GeV, the Higgs mass is estimated to lie close to 123-124 GeV. The theoretical uncertainty in this estimate is ±3 GeV. We highlight some LHC testable benchmark points which also display the presence of neutralino-stau coannihilation channel. [ABSTRACT FROM AUTHOR]

The ATLAS and CMS collaborations recently reported indication of a Higgs boson around 125GeV. If we add extra vector-like quarks to the MSSM, such a relatively heavy Higgs can be naturally realized in the GMSB framework, simultaneously explaining the muon g - 2 anomaly. I will discuss LHC prospect of this attractive model. [ABSTRACT FROM AUTHOR]

A make a qualitative study of the KT effect in the Higgs associative production with a W vector boson at the LHC. The kinematics are presented and the generalized form of the cross section is obtained. [ABSTRACT FROM AUTHOR]

The helecity amplitudes of the subprocess gg → γγ via scalar unparticles intermediate states are calculated. The differential cross section is compared to that of the standard model. Phenomenological implications are also discussed. [ABSTRACT FROM AUTHOR]

The contribution of the pure NCG forbidden subprocess gg → ZHis calculated. It is shown that the cross section becomes important at the LHC energies and depends strongly on the choice of the noncommutativity parameter. Because of the gluons luminosity inside the proton, it becomes comparable to that of the commutative standard model subprocess qq ZHfor reasonable values of the NCG parameter. [ABSTRACT FROM AUTHOR]

A pure NCG gluon fusion contribution to the Higgs production at large hadron colliders is discussed. It is shown that the NCG results become relevant at very high energies. This can be a good signal for the space-time non commutativity events. [ABSTRACT FROM AUTHOR]

Radiation resistant superconducting magnets are required for high intensity particle accelerators and associated secondary particle beamlines, such as the LHC upgrade and the COMET experiment at J-PARC. Expected neutron fluence on the superconducting coils reaches 1021 n/m2 or higher, therefore the magnet should be designed taking into account the irradiation effects. Irradiation tests for superconducting magnet materials have been carried out using reactor neutrons at Kyoto Univ. Research Reactor Institute. As a first step of the experiment, aluminum alloy stabilizer for superconducting cable was exposed to the reactor neutrons at low temperature and the resistance has been measured in situ during neutron exposure. After the irradiation at 12 K-15 K, the sample resistance increase was proportional to the integrated neutron fluence, and reached almost double for a fast-neutron fluence of 2.3×1020 n/m2 (>0.1 MeV). It is also confirmed that the induced resistance is fully recovered by thermal cycling to room temperature. Details of the irradiation test and the prospects are described. [ABSTRACT FROM AUTHOR]

The operation of the Large Hadron Collider superconducting magnets for current and high luminosity future applications relies on the cooling provided by helium-permeable cable insulations. These insulations take advantage of a He II micro-channels network constituting an extremely efficient path for heat extraction. In order to provide a fundamental understanding of the underlying thermal mechanisms, an experimental setup was built to investigate heat transport through single He II channels typical of the superconducting cable insulation network, where deviation from the macro-scale theory can appear. Micro-fabrication techniques were exploited to etch the channels down to a depth of ~ 16 ìm. The heat transport properties were measured in static pressurized He II and analyzed in terms of the laminar and turbulent He II laws, as well as in terms of the critical heat flux between the two regions. [ABSTRACT FROM AUTHOR]

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 energyrecovery type machine with two 1 km long straight acceleration sections. The 944 high field 2 K SC cavities dissipate 30 kW at CW operation. Eight 10 kW @ 4.5 K refrigerators are proposed. The particle detector contains a combined SC solenoid and dipole forming the cold mass and an independent liquid argon calorimeter. Cooling is done with two individual small sized cryoplants; a 4.5 K helium, and a 87 K liquid nitrogen plant. [ABSTRACT FROM AUTHOR]

The medium-modifications of processes characterized by the presence of a hard scale provide the most diverse tools to characterize the properties of the matter created in high-energy nuclear collisions. Indeed, jet quenching, the suppression of particles produced at high transverse momentum, has been established at RHIC almost a decade ago as one of the main tools in heavy-ion collisions. The melting of quarkonia is expected to provide also information about the temperature and the properties of the produced medium. The beginning of the LHC era for hot QCD studies starts with the first nuclear beams in 2010. The amount of information produced by this first run is overwhelming: The three experiments with nuclear program (ALICE, ATLAS and CMS) have provide new results in basically all subjects considered in previous experiments and have also shown the potential to make nuclear collisions at the TeV scale for the first time. I will review what the results from both RHIC and LHC imply for our understanding of hot and dense QCD matter from a theorists' perspective and how these new results change some of the concepts we developed in the last years. Particular attention is devoted to the case of jets, as the first data recently published from the LHC and the limitations of previous approaches call for a new theory of jets in a medium. [ABSTRACT FROM AUTHOR]

This is an auspicious moment in experimental particle physics - there are large data samples at the Tevatron and a new energy regime being explored at the Large Hadron Collider with ever larger data samples. The coincidence of these two events suggests that we will soon be able to address the question: what lies beyond the standard model? Particle physics's current understanding of the universe is embodied in it. The model has been tested to extreme precision - better than a part in ten thousand - but we suspect that it is only an approximation, and that physics beyond this standard model will appear in the data of the Tevatron and LHC in the near future. This brief review touches on the status of searches for new physics at the time of the conference. [ABSTRACT FROM AUTHOR]

The ATLAS detector is capable of resolving the highest energy pp collisions at luminosities sufficient to yield 10' of simultaneous interactions within a bunch collision lasting <0.5 nsec. Already in 2011 a mean occupancy of 20 is often found in pp running. In 2004 studies by ATLAS showed that the detector would have excellent performance also for the foreseeable particle multiplicities in the highest energy p-Pb and Pb-Pb collisions that the LHC will produce. These studies resulted in a letter of intent to the LHC committee by ATLAS to do physics with these beams also. In the past 2 years of data taking, ATLAS detector performance studies have confirmed these expectations at the actual multiplicities presented below. [ABSTRACT FROM AUTHOR]

The unprecedented center-of-mass energy available at the LHC offers unique opportunities for studying the properties of the strongly-interacting QCD matter created in PbPb collisions at extreme temperatures and very low parton momentum fractions. With its high precision, large acceptance for tracking and calorimetry, and a trigger scheme that allows analysis of each minimum bias PbPb event in the high-level trigger, CMS is fully equipped to study dimuon production in the high multiplicity environment of nucleus-nucleus collisions. Such probes are especially relevant for these studies since they are produced at early times and propagate through the medium, mapping its evolution. The capabilities of the CMS experiment to study dimuon production in pp and PbPb collisions based on LHC runs in 2010 and 2011 will be reviewed. In particular, CMS is able to measure prompt and non-prompt J/ψs, but also the first 3 γ states, differentially in pT and rapidity. In heavy ions, the observation of quarkonia at [formula] TeV will be presented, and the Z boson inclusive and differential measurement as probe of the initial state will be detailed. [ABSTRACT FROM AUTHOR]

The first heavy-ion run at the LHC with Pb+Pb collisions at [formula] TeV took place in the fall of 2010. In a short and relatively low luminosity run, the three detectors, ALICE, ATLAS and CMS showcased an impressive performance and produced a wealth of a high quality results. This article compares the new LHC results with those accumulated over the last decade at RHIC, focussing on the quantitative and qualitative differences between the different energy regimes of these two facilities. [ABSTRACT FROM AUTHOR]

We confront soft Pomeron and gluon saturation models with the first LHC data on inclusive hadron production. We claim that while the first type of models are not able to describe some part of the LHC data, the Colour-Glass-Condensate (gluon saturation) approach gives an adequate description of the data. Here, we compare our published predictions with the recently available 7 TeV data. We firmly believe that if further experimental measurements confirm that the gluon saturation works, it will be a major discovery. [ABSTRACT FROM AUTHOR]

Multivariate machine learning techniques provide an alternative to the rapidity gap method for event-by-event identification and classification of diffraction in hadron-hadron collisions. Traditionally, such methods assign each event exclusively to a single class producing classification errors in overlap regions of data space. As an alternative to this so called hard classification approach, we propose estimating posterior probabilities of each diffractive class and using these estimates to weigh event contributions to physical observables. It is shown with a Monte Carlo study that such a soft classification scheme is able to reproduce observables such as multiplicity distributions and relative event rates with a much higher accuracy than hard classification. [ABSTRACT FROM AUTHOR]

The observation of diffraction at LHC with the CMS detector at [formula] and 2360 GeV is presented, along with a comparison of the data with the predictions of the PYTHIA and PHOJET generators. [ABSTRACT FROM AUTHOR]

The role of multi Pomeron interactions in the formation of soft scattering unitarity models is summarized. GLMM predictions for LHC and beyond are presented and compared with other relevant models. [ABSTRACT FROM AUTHOR]

We calculate observables relevant for forward jets at LHC. The simulations are performed using Monte Carlo event generators. In particular we compare results from CASCADE based on high energy factorization and PYTHIA which is based on collinear factorization. [ABSTRACT FROM AUTHOR]

Following a 15 year programme of intensive research into diffractive electron-proton scattering at HERA, it is important to transfer the knowledge and experience gained into the LHC programme. This contribution raises some current issues in diffraction at the LHC and suggests ways in which they might be addressed using HERA results. [ABSTRACT FROM AUTHOR]

Improving our understanding and modeling of the underlying event in high energy collider environment is important for more precise measurements at the LHC. CDF Run II data for the underlying event associated with Drell-Yan lepton pair production and early ATLAS data measuring underlying event activity with respect to the leading transverse momentum track are presented. The data are compared with several QCD Monte Carlo models. It is seen that no current standard Monte Carlo tune adequately describes all the early ATLAS data and CDF data simultaneously. The underlying event observables presented here are particularly important for constraining the energy evolution of multiple parton interaction models. [ABSTRACT FROM AUTHOR]

A summary of the LHC and CMS detector performance is given and the first CMS results are presented. In particular, emphasis will be given to low-pt QCD Physics including charged hadron spectra, the measurement of Bose-Einstein (BEC) and angular Correlations, and of underlying event properties. [ABSTRACT FROM AUTHOR]

We study the phenomenology of a four-site Higgsless model, an extension of the minimal three-site version (BESS model), at the present operating colliders. The model predicts the existence of two neutral and four charged extra gauge bosons, Z1,2 and W1,2±. In contrast to other Higgsless models, sizeable fermion-boson couplings are still allowed by the electroweak precision data and make discovery possible in the next two years in the favoured Drell-Yan channels at the 7 TeV LHC for masses in the TeV region depending on the model parameters. [ABSTRACT FROM AUTHOR]

We discuss the signatures of the spin-2 graviton excitations predicted by the Randall-Sundrum model with one warped extra dimension, in dilepton and diphoton production at LHC. By using a specific angular analysis, we assess the ranges in mass and coupling constant where such gravitons can be discriminated against competitor spin-1 and spin-0 objects, that potentially could manifest themselves in these processes with the same mass and rate of events. Depending on the value of the coupling constant to quarks and leptons, the numerical results indicate graviton identification mass ranges up to 1.1-2.4 TeV and 1.6-3.2 TeV for LHC nominal energy of 14 TeV and time-integrated luminosity of 10 and 100fb-1, respectively. [ABSTRACT FROM AUTHOR]

The tree-level flavour-changing neutral currents in the two-Higgs-doublet models can be suppressed by protecting the breaking of either flavour or flavour-blind symmetries, but only the first choice, implemented by the application of the Minimal Flavour Violation hypothesis, is stable under quantum corrections. Moreover, a two-Higgs-doublet model with Minimal Flavour Violation enriched with flavour-blind phases can explain the anomalies recently found in the ΔF = 2 transitions, namely the large CP-violating phase in Bs mixing and the tension between [variant_greek_epsilon]K and SψKS. [ABSTRACT FROM AUTHOR]

Precision studies of Drell-Yan production of high-transverse momentum leptons at hadron colliders require that electroweak and QCD higher-order contributions are simultaneously taken into account in theoretical predictions and data analysis. A detailed phenomenological study of the impact of electroweak and strong contributions, as well as of their combination, to the most important observables relevant for single W and Z physics programme at hadron colliders is presented. [ABSTRACT FROM AUTHOR]

We present the first studies of decays of the type B→DX, where D represents a charmed meson (D0, D(*)+, or Ds) from the LHCb experiment at CERN. Our studies use data accumulated during the 2010 run of the LHC. This work represents the first steps on a programme towards a precision measurement of the angle γ of the CKM Unitarity Triangle. The prospects for this γ measurement will be reviewed. [ABSTRACT FROM AUTHOR]

The first measurements of charged particle production in proton-proton collisions at center-of-mass energy [formula] and 7 TeV recorded with the ATLAS detector at the LHC are presented. Minimum bias distributions are measured for events with at least one charged particle in the kinematic range |η| <2.5 and pT>500 MeV and compared with the predictions from various Monte Carlo models. Activity in the underlying event was measured with respect to the highest pT track in the event. Both the minimum bias and underlying event measurements are fully corrected for detector effects to obtain distributions at the hadron level. A new PYTHIA6 Monte Carlo tune, ATLAS Minimum Bias Tune 1, was produced using ATLAS minimum bias distributions measured in a diffractive limited phase-space in combination with measurements from previous hadron collider experiments. The new tune is shown to significantly improve the predictions for minimum bias distributions measured in the diffractive limited phase-space. [ABSTRACT FROM AUTHOR]

At the LHC, tau leptons are expected in final states of many important physics processes including Supersymmetry and the production of Higgs boson(s) and other exotic particles. An efficient and accurate τ reconstruction and identification are therefore an important part of the CMS physics programme. Z0→τ+τ- decays are often considered the 'standard candle' of tau reconstruction as they validate tau lepton identification and provide a test bench for Higgs searches (for which they constitute the main irreducible background). We describe techniques for selecting and reconstructing the Z0→τ±τ∓→μ±νμντ(νμντ)+τ-jet∓ντ(ντ) events that were developed for the measurement of the Z production cross-section by the CMS experiment using 200 pb-1 of the LHC collision data at the center-of-mass energy s = 10 TeV. We validate these techniques using simulated events and present a data-driven method for estimating background contributions to this measurement. [ABSTRACT FROM AUTHOR]

Muon signatures are extremely important in the challenging environment of collisions at the LHC. Understanding the observed muon yield from Standard Model processes is the first task for all analyses involving muons. Basic muon kinematical observables are presented for the first CMS data at [formula] and compared with Monte Carlo expectations. The muon sample composition is studied by using the MC truth in terms of muons from heavy flavours, muons from light hadron decays and hadron punch-through is studied from MC truth. [ABSTRACT FROM AUTHOR]

We will review the main results obtained so far within the ALICE experiment at the CERN's Large Hadron Collider. [ABSTRACT FROM AUTHOR]

The ALICE potentials in proton-proton collisions for the measurement of the fraction of J/ψ produced at central rapidity (|y|<0.9) in beauty hadrons semi-inclusive decays, namely B→J/ψX, is discussed. This measurement relies on the combined use of the Time Projection Chamber (TPC), for tracking and particle identification via dE/dx measurement; the Inner Tracking System (ITS) for tracking and detection of displaced vertices; the Transition Radiation Detector (TRD) for particle identification. The description of the analysis method developed and the discussion of the estimate for a total J/ψ statistics corresponding to one year of ALICE data taking in p-p collisions at s = 7 TeV is provided in the article. [ABSTRACT FROM AUTHOR]

The ALICE experiment is dedicated to the study of heavy-ion collisions at LHC energies. ALICE has a high-quality hadron identification system in the central region e.g. a Inner Tracking System, a large Time-Projection-Chamber, a Time-Of-Flight and the High Momentum Particle Identification Detector (HMPID). The ALICE HMPID detector has been designed to identify charged hadrons (ρ, K, p) in the momentum range 1s = 7 TeV and its future contribution to the ALICE physics programme, will be presented. [ABSTRACT FROM AUTHOR]

One shows that relativistic heavy ion collisions could be used as an experimental probe to detect fundamental properties of spacetime long speculated about. The results rely on the recent proposal that magnetic fields of intensity much larger than that of magnetars should be produced at the beginning of the collisions and this could have an important impact on the experimental manifestation of a noncommutative spacetime. Indeed, in the noncommutative generalization of electrodynamics the interplay between a nonzero noncommutative parameter and an external magnetic field leads us to predict the production of lepton pairs of low invariant mass by free photons (an event forbidden by Lorentz invariant electrodynamics) in relativistic heavy ion collisions at present and future available energies. This unique channel can be clearly considered as a signature of noncommutativity. [ABSTRACT FROM AUTHOR]

After more than 20 years of continuous work and several months of commissioning with cosmic muon data, the ATLAS experiment started data taking at the Large Hadron Collider (CERN). From November 2009 to May 2010, ATLAS registered proton-proton collisions at 900 GeV, 2.36 GeV and finally 7 TeV center of mass energy. These data samples have been used to study the detector performance in detail and are currently being used also for the first physics studies. In this document, we present some selected physics and performance results obtained with the first 7 TeV proton-proton collisions. [ABSTRACT FROM AUTHOR]