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Abstract: Many highly developed Monte Carlo tools for the evaluation of cross sections based on tree matrix elements exist and are used by experimental collaborations in high energy physics. As the evaluation of one-loop matrix elements has recently been undergoing enormous progress, the combination of one-loop matrix elements with existing Monte Carlo tools is on the horizon. This would lead to phenomenological predictions at the next-to-leading order level. This note summarises the discussion of the next-to-leading order multi-leg (NLM) working group on this issue which has been taking place during the workshop on Physics at TeV Colliders at Les Houches, France, in June 2009. The result is a proposal for a standard interface between Monte Carlo tools and one-loop matrix element programs. Dedicated to the memory of, and in tribute to, Thomas Binoth, who led the effort to develop this proposal for Les Houches 2009. Thomas led the discussions, set up the subgroups, collected the contributions, and wrote and edited this paper. He made a promise that the paper would be on the arXiv the first week of January, and we are faithfully fulfilling his promise. In his honour, we would like to call this the Binoth Les Houches Accord. [Copyright &y& Elsevier]

Abstract: Models with large extra dimensions as well as unparticle models could give rise to new phenomena at collider experiments due to real emission or virtual exchange of gravitons or unparticles. In this paper we present the common implementation of these processes in the Monte Carlo generator Pythia8, using relations between the parameters of the two models. The program offers several options related to the treatment of the UV region of the effective theories, including the possibility of using a form factor for the running gravitational coupling. Characteristic results obtained with Pythia8 have been used to validate the implementations as well as to illustrate the key features and effects of the model parameters. The results presented in this paper are focused on mono-jet, di-photon and di-lepton final states at the LHC. [Copyright &y& Elsevier]

Predicting the evolutionary dynamics of the COVID-19 pandemic is a complex challenge. The complexity increases when the vaccination process dynamic is also considered. In addition, when applying a voluntary vaccination policy, the simultaneous behavioral evolution of individuals who decide whether and when to vaccinate must be included. In this paper, a coupled disease-vaccination behavior dynamic model is introduced to study the coevolution of individual vaccination strategies and infection spreading. We study disease transmission by a mean-field compartment model and introduce a non-linear infection rate that takes into account the simultaneity of interactions. Besides, the evolutionary game theory is used to investigate the contemporary evolution of vaccination strategies. Our findings suggest that sharing information with the entire population about the negative and positive consequences of infection and vaccination is beneficial as it boosts behaviors that can reduce the final epidemic size. Finally, we validate our transmission mechanism on real data from the COVID-19 pandemic in France. • A new couple disease-vaccination behavior model is introduced. • A compartment model with a new nonlinear infection rate is proposed to study the disease transmission. • An evolutionary game theory approach is implemented to study the simultaneous evolution of people vaccination strategies. • Two rules for updating vaccination strategy are studied: one based on local imitation; the other based on global considerations. • The infection transmission mechanism is validated with French COVID-19 data. [ABSTRACT FROM AUTHOR]

The relationship between environmental degradation and economic growth has become a prominent topic in recent decades, increasing multidisciplinary approaches across a wide range of studies. Analyzing the economy-environment nexus is significant because most countries attempt to limit environmental deterioration while pursuing economic growth. This paper studies the non-linear cross-correlations between economic growth and environmental degradation on a sample of five developed European countries - France, Germany, Spain, Norway, and the United Kingdom. The study is performed using two approaches: multifractal detrended cross-correlation analysis and wavelet-based analysis. According to the empirical tests, there are non-linear cross-correlations between economic growth and environmental degradation in all five countries. For each country, multifractal metrics such as Hurst exponents, scaling exponents, and multifractal spectra are computed to show the significance of all time-series pairs. The strongest multifractal features have been observed in France, Norway, and Spain. Shuffling the series suggests that multifractality in the cross-correlations arises both from a broad probability density function and from different long-term correlations. Wavelets are applied to detrend all data sets before computing the cross-correlation. Moreover, the wavelet coherence is computed as a measure for analyzing interdependencies across time and frequencies. Except for France and Spain, Wavelet-detrended cross-correlation values are considerably lower than cross-correlation values of the raw data sets, which indicates that the interdependence between growth and environmental degradation is rather long-term. In terms of wavelet coherence, results vary among the countries, with France and Spain showing the highest and most persistent coherence values. [ABSTRACT FROM AUTHOR]

The discovery of the origin of electroweak symmetry breaking, realized in the Standard Model and in some models beyond this theory by the Higgs mechanism, is one of the main goals of the ATLAS experiment at the Large Hadron Collider. This mechanism predicts the existence of one or more scalar particles, the Higgs boson(s). Higgs boson decay modes to tau leptons, such as , are very important as they could play a crucial role in searches within the challenging 120 – 140 GeV mass region. This channel is also important in supersymmetric extensions of the Standard Model through the associated production of the Higgs bosons with heavy quarks or by gluon fusion. Finally, the observation of a charged Higgs boson would constitute irrefutable evidence for physics beyond the Standard Model. A light charged Higgs boson would be produced in top quark decays through , and would be likely to decay to a tau lepton and a neutrino. This paper summarizes recent ATLAS studies focusing on the above channels and concentrates on several experimental aspects of these analyses. [ABSTRACT FROM AUTHOR]

Studies of Z bosons decaying to τ leptons constitute a test of the Standard Model (SM) in the new LHC energy regime as well as a benchmark process for searches. This paper describes the first results of studies performed with of integrated luminosity collected with CMS detector up to end of Summer 2010. [ABSTRACT FROM AUTHOR]

The upgrade for ATLAS detector will undergo different phases towards super-LHC. The first upgrade for the Pixel detector will consist of the construction of a new pixel layer which will be installed during the first shutdown of the LHC machine (LHC phase-I upgrade). The new detector, called Insertable B-Layer (IBL), will be inserted between the existing pixel detector and a new (smaller radius) beam-pipe at a radius of 3.3 cm. The IBL will require the development of several new technologies to cope with increase of radiation or pixel occupancy and also to improve the physics performance which will be achieved by reducing the pixel size and of the material budget. Three different promising sensor technologies (planar-Si, 3D-Si and diamond) are currently under investigation for the pixel detector. An overview of the project with particular emphasis on the pixel module is presented in this paper. [ABSTRACT FROM AUTHOR]

Future experiments at the European Organization for Nuclear Research (CERN) will increase the demand for high-bandwidth optical links due to the growing amounts of data to be treated by the data-transmission and acquisition systems. The development of the Giga Bit Laser Driver (GBLD) chip-set addresses this issue providing a means to increase the bandwidth available to transmit data to and from the counting room. This paper describes some aspect of test setup implementation and the protocol test used to evaluate and qualify the GBLD. [ABSTRACT FROM AUTHOR]

In November and December 2009, the LHC delivered the first proton–proton collisions with beams of 450 GeV and then of 1.18 TeV, an unprecedented energy. On the 30th of March 2010, LHC operation moved forward to the physics era with collisions at a 7 TeV center of mass energy and, by the time of the IPRD10 conference, an integrated luminosity of was accumulated. This paper relates how the CMS data reconstruction and Monte-Carlo simulations were validated in only few months. It presents the first physics results. [ABSTRACT FROM AUTHOR]

Gossip is a gaseous micro-pixel detector with a very thin drift gap intended for a high rate environment like at the pixel layers of ATLAS at the sLHC. The detector outputs not only the crossing point of a traversing MIP, but also the angle of the track, thus greatly simplifying track reconstruction. In this paper we describe a testbeam experiment to examine the angular resolution of the reconstructed track segments in Gossip. We used here the low diffusion gas mixture DME/CO2 50/50. An angular resolution of 20 mrad for perpendicular tracks could be obtained from a 1.5 mm thin drift volume. However, for the prototype detector used at the testbeam experiment, the resolution of slanting tracks was worsened by poor time resolution of the pixel chip used. [ABSTRACT FROM AUTHOR]

ATLAS is a general purpose experiment at the Large Hadron Collider (LHC) at CERN which began operation in September, 2009. ATLAS has a large muon spectrometer which is designed to measure muon momentum with a resolution ranging from 3% at 100 GeV/c to 10% at 1 TeV for a pseudorapidity range of 0-2.7. In this paper, we describe the derivation and validation of calibration constants for the Monitored Drift Tubes (MDTs) in the ATLAS muon spectrometer for use with initial LHC collisions. At LHC start-up, the luminosity was not sufficient for ordinary calibrations with collision muons, and so alternative methods were developed. The time-to-space (RT) functions were obtained from the University of Michigan gas monitor chamber and the (s) were derived from LHC beamsplash events from 2009 and 2010. We have validated these calibration constants by performing muon track reconstruction using 900 GeV collision data from December, 2009 and 7 TeV data from 2010. We find that these calibration constants yield an MDT chamber hit resolution of 142 μm and a residual width of 91 μm. [ABSTRACT FROM AUTHOR]

It is expected that at SLHC the number of detector channels in the ATLAS Semiconductor Tracker will increase by a factor 10, to cope with the increased luminosity. Currently every detector module has its own power cable, known as independent powering (IP). In the upgrade, this arrangement will no longer be tenable, due to cable volume and power losses. The serial powering alternative scheme, in which supermodules, with many readout hybrids, are connected in a serially powered chain, has been proposed and actively pursued over the last few years by the ATLAS Tracker Upgrade Community. This scheme presents some benefits, including simplicity, lower mass and reduced power losses. On the other hand, grounding, shielding and data transmission schemes are modified with respect to the conventional arrangement. Custom components specifically for serial powering have been produced, including the ABCN-25 readout ASICs and the SPI serial powering regulation ASIC, both in 250 nm CMOS, a dedicated programmable current source and power protection elements. In this paper the latest measurements from testing of the new custom electronics are presented and future plans are outlined. [ABSTRACT FROM AUTHOR]

In this paper, the potential to study hadroproduction of charmonium via decay at the LHC is discussed. The branching ratio of is estimated to be about . The studies of charmonium hadroproduction using and are compared. The yield of is estimated to be about 60 events/pb−1 at . [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a software environment to automatically configure and run online triggering and dataflow farms for the ATLAS experiment at the Large Hadron Collider (LHC). It provides support for a broad set of users, with distinct knowledge about the online triggering system, ranging from casual testers to final system deployers. This level of automatization improves the overall ATLAS TDAQ work flow for software and hardware tests and speeds-up system modifications and deployment. [ABSTRACT FROM AUTHOR]

Recent results from the ATLAS experiment at the CERN Large Hadron Collider are presented. The experiment has been functioning with high efficiency since the start of LHC data-taking, at proton-proton centre-of-mass energies of 900 GeV and 2.36 TeV (2009) and 7 TeV (2010). This paper provides a brief overview of the highlights of recent detector performance and physics measurements. [ABSTRACT FROM AUTHOR]

The Large Hadron Collider (LHC) has opened up a new kinematic regime. Using high energy proton-proton collisions it is possible to search for hitherto unobserved particles and processes at the TeV scale. This paper describes search strategies for a range of exotic phenomena proposed within supersymmetry and other theories. [ABSTRACT FROM AUTHOR]

Theoretical considerations and experimental measurements indicate the importance of charged hadron identification in the higher pT region (namely ). Since the PID capability of the present ALICE experiment at LHC (CERN) is based on statistical methods at large transverse momenta, the construction of a new detector to improve the track by track PID capability is very much supported. This task can be fulfilled by a gaseous ring imaging Cherenkov (RICH) detector. However, high-pT events are very rare, thus to enrich the statistics of the rare high pT events in the recorded data sample the construction of a dedicated trigger unit for the RICH detector is strongly recommended. To select the high-pT events the basic idea is to detect the inclination of the charged particle trajectories in the ALICE magnetic field with respect to the direction of the collision point. If the inclination is smaller than a threshold, the transverse momentum of the propagating particle is larger than a certain value. A prototype chamber using Thick Gas Electron Multiplier layers was built to test the operation principle of the High-pT Trigger Detector. The prototype was tested at the CERN PS beam facility. We present results of the operation tests and data taking. Monte Carlo simulations in the ALIROOT framework are also performed in order to optimize the geometry and segmentation of the detector we present here. In this paper we summarizes our efforts to develop the High-pT Trigger Detector. [Copyright &y& Elsevier]

The LHCb experiment at the CERN Large Hadron Collider employs two Ring Imaging Cherenkov (RICH) detectors for particle identification. The first covers the charged particle momentum range using aerogel and C 4 F 10 radiators and the second covers up to 100 GeV/c using CF 4. Cherenkov light will be detected using a novel type of position sensitive device: the pixel Hybrid Photon Detector (HPD). In the pixel HPD, photoelectrons are produced in a multialkali photocathode, accelerated and focused by an electrostatic field, and then detected by a pixelated silicon detector which is bump-bonded onto a 40 MHz read-out chip. This paper reports on the development of the LHCb RICH detectors and the performance of the HPDs. [Copyright &y& Elsevier]

The reconstruction and identification of electrons and photons will be one of the key issues at the start-up of data-taking with ATLAS at the LHC, in 2009. In this paper, the issues related to energy and position reconstruction, particle identification and background rejection will be briefly reviewed. [Copyright &y& Elsevier]

The implementation of a trigger for hadronically decaying tau leptons at the Large Hadronic Collider (LHC) is challenging due to the high background rate, on the other hand it increases tremendously the discovery potential of ATLAS in searches for Standard Model (SM) or Supersymmetric (SUSY) Higgs or other more exotic final states. In this paper we describe the ATLAS tau trigger system, focusing on the early data taking period, and present results from studies based on GEANT 4 simulated events, including trigger rates and the acceptance of tau leptons from SM processes. In order to cope with the rate and optimize the efficiency of important physics channels, the results of the current simulation studies indicate that ATLAS tau triggers should include either relatively high transverse momentum single tau signatures, or low transverse momentum tau signatures in combination with other signatures, such as missing transverse energy, leptons, or jets. [Copyright &y& Elsevier]

Abstract: By the time of CCP 2008, the largest scientific machine in the world – the Large Hadron Collider – had been cooled down as scheduled to its operational temperature of below 2 degrees Kelvin and injection tests were starting. Collisions of proton beams at were expected within one to two months of the initial tests, with data taking at design energy () foreseen for 2009. In order to process the data from this world machine, we have put our “Higgs in one basket” – that of Grid computing [The Worldwide LHC Computing Grid (WLCG), in: Proceedings of the Conference on Computational Physics 2006 (CCP 2006), vol. 177, 2007, pp. 219–223]. After many years of preparation, 2008 saw a final “Common Computing Readiness Challenge” (CCRC''08) – aimed at demonstrating full readiness for 2008 data taking, processing and analysis. By definition, this relied on a world-wide production Grid infrastructure. But change – as always – is on the horizon. The current funding model for Grids – which in Europe has been through 3 generations of EGEE projects, together with related projects in other parts of the world, including South America – is evolving towards a long-term, sustainable e-infrastructure, like the European Grid Initiative (EGI) [The European Grid Initiative Design Study, website at http://web.eu-egi.eu/]. At the same time, potentially new paradigms, such as that of “Cloud Computing” are emerging. This paper summarizes the results of CCRC''08 and discusses the potential impact of future Grid funding on both regional and international application communities. It contrasts Grid and Cloud computing models from both technical and sociological points of view. Finally, it discusses the requirements from production application communities, in terms of stability and continuity in the medium to long term. [Copyright &y& Elsevier]

The experiments at the Large Hadron Collider LHC have a large discovery potential for physics beyond the Standard Model and in the investigation of the nature of electroweak symmetry breaking. The large event rates provided by the high luminosity LHC machine will, however, also allow to perform precision measurements of important Standard Model parameters. Both the discovery potential for new physics and the measurements of Standard Model parameters are summarized in the present paper, with a particular focus on what can be achieved during the first years. [Copyright &y& Elsevier]

In this paper the precision of the theoretical control of the lepton pair production processes in proton-proton collisions is analysed and an optimal kinematic region is proposed for the precision luminosity measurement at the LHC collider. [Copyright &y& Elsevier]

In this paper the analysis of certain logarithmic expansions, which developed for precision studies of the evolution of the QCD parton distributions (pdf) at the Large Hadron Collider, is used. The data of the CCFR collaboration is used to parameterize the non-singlet parton distributions in this order. In the fitting procedure, Bernstein polynomial method is employed. The results of valence quark distributions in the NLO are compered with exact and truncated solutions for non-singlet case. [Copyright &y& Elsevier]

• Developed deep learning-based models to forecast emergency department overcrowding. • Eight deep learning models have been compared for ED visits forecasting. • Real Datasets from the ED at CHRU Lille, France, investigated to serve the case study. • Two types of forecasting are conducted: one- and multi-step-ahead forecasting. • Results show the superior performance of the VAE compared to the other algorithms. As the demand for medical cares has considerably expanded, the issue of managing patient flow in hospitals and especially in emergency departments (EDs) is certainly a key issue to be carefully mitigated. This can lead to overcrowding and the degradation of the quality of the provided medical services. Thus, the accurate modeling and forecasting of ED visits are critical for efficiently managing the overcrowding problems and enable appropriate optimization of the available resources. This paper proposed an effective method to forecast daily and hourly visits at an ED using Variational AutoEncoder (VAE) algorithm. Indeed, the VAE model as a deep learning-based model has gained special attention in features extraction and modeling due to its distribution-free assumptions and superior nonlinear approximation. Two types of forecasting were conducted: one- and multi-step-ahead forecasting. To the best of our knowledge, this is the first time that the VAE is investigated to improve forecasting of patient arrivals time-series data. Data sets from the pediatric emergency department at Lille regional hospital center, France, are employed to evaluate the forecasting performance of the introduced method. The VAE model was evaluated and compared with seven methods namely Recurrent Neural Network (RNN), Long short-term memory (LSTM), Bidirectional LSTM (BiLSTM), Convolutional LSTM Network (ConvLSTM), restricted Boltzmann machine (RBM), Gated recurrent units (GRUs), and convolutional neural network (CNN). The results clearly show the promising performance of these deep learning models in forecasting ED visits and emphasize the better performance of the VAE in comparison to the other models. [ABSTRACT FROM AUTHOR]

The CMS pixel detector consists of 15840 readout chips, containing a total of almost 66 million pixels. In this paper, I describe the preparation for the first data-taking with LHC beams, in which the performance of the readout chips was optimized using a suite of calibrations. The detector thresholds have been adjusted to be less than 3000 electrons, and the effect of timing on the thresholds has been studied. After the arrival of LHC beam in December of 2009, the timing of the detector was optimized to achieve maximum efficiency, using both online and offline analysis. I will also discuss the challenges presented by beam backgrounds. [ABSTRACT FROM AUTHOR]

After joining a series of Computing scale tests during last years, steered by the Worldwide LHC Computing Grid, the CMS Computing project is ready to enter into the LHC data taking era. With the real LHC collisions at centre-of-mass energies up to 7 TeV, CMS Computing collected more experience on the Tier-0 tape writing and processing capabilities, on the behaviour of the Tier-1 sites in terms of tape archival operations as well as reprocessing and skimming, on the optimization of the datasets distribution on a full-mesh transfer topology, on the performance of a world-wide Grid-enabled distributed analysis of real LHC data. In this paper, the first Computing lessons learned with LHC collisions data at 7 TeV are presented. [ABSTRACT FROM AUTHOR]