H. Kirschenmann

Measurements of the jet energy scale in CMS and the status of the jet energy corrections for 2011 analyses are presented. The measurements have been performed with a data sample collected in proton-proton collisions at a centre-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 4.9fb−1. Dijet and photon/Z+jets events are used to measure the jet energy response in the CMS detector. The results are presented for the Particle Flow approach, which attempts to reconstruct individually each particle in the event, prior to the jet clustering, based on information from all relevant subdetectors.

The reconstruction and calibration of jets relies critically on the interplay between the tracking detectors, central calorimeters and forward calorimeters. Therefore, CMS makes use of the “Particle Flow” approach to optimally combine the information from the different subdetectors. A summary of the measurements of the jet energy calibration in CMS is presented, performed with data samples collected in proton-proton collisions at a center-of-mass energy of 8 TeV corresponding to an integrated luminosity of 19.8 fb−1. The final jet energy calibration is based on dijet, γ+jet and Z+jet events. The effect of pileup interactions and the state of the art mitigation techniques used in CMS are presented and we describe the main sources of uncertainty on the jet energy calibration.

The European Committee for Future Accelerators (ECFA) Early Career Researcher's (ECR) panel, which represents the interests of the ECR community to ECFA, officially began its activities in January 2021. In the first two years, the panel has defined its own internal structure, responded to ECFA requests for feedback, and launched its own initiatives to better understand and support the diverse interests of early career researchers. This report summarises the panel composition and structure, as well as the different activities the panel has been involved with during the first two years of its existence.

Abstract Precise measurements of the energy of jets emerging from particle collisions at the LHC are essential for a vast majority of physics searches at the CMS experiment. In this study, we leverage well-established deep learning models for point clouds and CMS open data to improve the energy calibration of particle jets. To enable production-ready machine learning based jet energy calibration an end-to-end pipeline is built on the Kubeflow cloud platform. The pipeline allowed us to scale up our hyperparameter tuning experiments on cloud resources, and serve optimal models as REST endpoints. We present the results of the parameter tuning process and analyze the performance of the served models in terms of inference throughput, providing insights for future work in this direction. The study also demonstrates improvements in both flavor dependence and resolution of the energy response when compared to the standard jet energy corrections baseline.

Abstract Precise measurements of the energy of jets emerging from particle collisions at the LHC are essential for a vast majority of physics searches at the CMS experiment. In this study, we leverage well-established deep learning models for point clouds and CMS open data to improve the energy calibration of particle jets. To enable production-ready machine learning based jet energy calibration an end-to-end pipeline is built on the Kubeflow cloud platform. The pipeline allowed us to scale up our hyperparameter tuning experiments on cloud resources, and serve optimal models as REST endpoints. We present the results of the parameter tuning process and analyze the performance of the served models in terms of inference time and overhead, providing insights for future work in this direction. The study also demonstrates improvements in both flavor dependence and resolution of the energy response when compared to the standard jet energy corrections baseline.

This report presents a compilation of selected recent Standard Model measurements, including findings by ATLAS, CMS, LHCb, and H1. Covered topics include QCD studies using jets, photons, and vector bosons, and the latest measurements of the strong coupling constant. Additionally, it includes a status update on the precision measurements of the W-boson and top-quark masses. It presents recent findings on inclusive multiboson production, studies in vector boson scattering, and selected top-quark physics results. These measurements and studies are crucial for rigorous testing of the Standard Model, and any deviations from the Standard Model predictions could indicate the presence of New Physics phenomena.

This document reports the first year of activity of the VBSCan COST Action network, as summarised by the talks and discussions happened during the VBSCan Thessaloniki 2018 workshop. The VBSCan COST action is aiming at a consistent and coordinated study of vector-boson scattering from the phenomenological and experimental point of view, for the best exploitation of the data that will be delivered by existing and future particle colliders.

The European Committee for Future Accelerators (ECFA) Early-Career Researchers (ECR) Panel was invited by the ECFA Detector R&D Roadmap conveners to collect feedback from the European ECR community. A working group within the ECFA ECR panel held a Townhall Meeting to get first input, and then designed and broadly circulated a detailed survey to gather feedback from the larger ECR community. A total of 473 responses to this survey were received, providing a useful overview of the experiences of ECRs in instrumentation training and related topics. This report summarises the feedback received, and is intended to serve as an input to the ECFA Detector R&D Roadmap process.

Recent results from searches for supersymmetry in final states with one or more leptons by the ATLAS and CMS collaborations are reported. The data for these results has been recorded in 2015 at √ s = 13 TeV and amounts to an integrated luminosity of 2.2 2.3 fb−1 for the CMS experiment and 3.2 fb−1 for the ATLAS experiment. The results are interpreted in simplified models. Presented at Moriond/EW2016 51st Rencontres de Moriond on Electroweak Interactions and Unified Theories SEARCHES FOR SUPERSYMMETRY IN EVENTS WITH ONE OR MORE LEPTONS USING THE ATLAS AND CMS EXPERIMENTS HENNING KIRSCHENMANN, on behalf of the ATLAS and CMS collaborations CERN, CH-1211 Geneva 23, Switzerland Recent results from searches for supersymmetry in final states with one or more leptons by the ATLAS and CMS collaborations are reported. The data for these results have been recorded in 2015 at √ s = 13 TeV and amount to an integrated luminosity of 2.2−2.3 fb−1 for the CMS experiment and 3.2 fb−1 for the ATLAS experiment. The results are interpreted in simplified models.

Jet reconstruction and calibration in the CMS experiment are complicated by the nonlinear response of the calorimeters and high pileup conditions. These difficulties are mitigated at CMS by utilising the particle flow approach. The jet energy calibration from data is summarized. It is performed with data samples collected in proton-proton collisions at a centre-of-mass energy of 8 TeV corresponding to an integrated luminosity of 11 fb−1. The final jet energy calibration is derived with dijet, γ+jet and Z+jet events. Here, we focus on the estimation of the inter-η-calibration using dijet events and discuss the uncertainties on the jet energy corrections.

In preparation for collecting proton-proton collisions from the LHC at a center-of-mass energy of 13 TeV and rate of 40MHz with increasing instantaneous luminosity, the CMS collaboration prepared an array of triggers utilizing jets and missing transverse energy for searches for new physics at the energy frontier as well as for SM precision measurements. The CMS trigger system must be able to sift through the collision events in order to extract events of interest at a rate of 1kHz, applying sophisticated algorithms adapted for fast and effective operation. Particularly important is the calibration of the trigger objects, as corrections to the measured energy may be substantial. Equally important is the development of improved reconstruction algorithms to mitigate negative effects due to high numbers of overlapping proton-proton collisions and increased levels of beam-related effects. Work by the CMS collaboration on upgrading the high-level trigger for jets and missing transverse energy for the upgraded LHC operation will be presented, along with the improved performance of these triggers.

The European Committee for Future Accelerators (ECFA) Early Career Researcher's (ECR) panel, which represents the interests of the ECR community to ECFA, officially began its activities in January 2021. In the first two years, the panel has defined its own internal structure, responded to ECFA requests for feedback, and launched its own initiatives to better understand and support the diverse interests of early career researchers. This report summarises the panel composition and structure, as well as the different activities the panel has been involved with during the first two years of its existence.

The study of the associated production of vector bosons and jets constitutes an excellent testbench to check numerous QCD predictions. Measurements of the total and differential cross sections of vector bosons produced in association with jets have been performed at 13 TeV center-of-mass energies with the CMS experiment at the LHC. Differential distributions as function of a broad range of kinematical observables are measured and compared with theoretical predictions. Final states with a vector boson and jets can be also used to study electroweak initiated processes, such as the vector boson fusion production of a Z boson that is accompanied by a pair of energetic jets having large invariant mass.

This document reports the first year of activity of the VBSCan COST Action network, as summarised by the talks and discussions happened during the VBSCan Thessaloniki 2018 workshop. The VBSCan COST action is aiming at a consistent and coordinated study of vector-boson scattering from the phenomenological and experimental point of view, for the best exploitation of the data that will be delivered by existing and future particle colliders.

This document reports the first year of activity of the VBSCan COST Action network, as summarised by the talks and discussions happened during the VBSCan Thessaloniki 2018 workshop. The VBSCan COST action is aiming at a consistent and coordinated study of vector-boson scattering from the phenomenological and experimental point of view, for the best exploitation of the data that will be delivered by existing and future particle colliders.

This document reports the first year of activity of the VBSCan COST Action network, as summarised by the talks and discussions happened during the VBSCan Thessaloniki 2018 workshop. The VBSCan COST action is aiming at a consistent and coordinated study of vector-boson scattering from the phenomenological and experimental point of view, for the best exploitation of the data that will be delivered by existing and future particle colliders.

Recent measurements performed by the ATLAS and CMS collaborations on the Run 2 dataset are testing QCD with unprecedented precision. The wealth of data, an ever-improving experimental understanding of jets and photons, and novel measurements of jet substructure enable an improved understanding.

Recent measurements performed by the ATLAS and CMS collaborations on the Run 2 dataset are testing QCD with unprecedented precision. The wealth of data, an ever-improving experimental understanding of jets and photons, and novel measurements of jet substructure enable an improved understanding.