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Search for production and constraints on the Yukawa couplings of light quarks to the Higgs boson
No full textA search for production is performed with data from the CMS experiment at the LHC corresponding to an integrated luminosity of 138 fb at a proton-proton center-of-mass collision energy of 13 TeV. The analysis focuses on the topology of a boosted Higgs boson recoiling against a high-energy photon. The final states of and are analyzed. This study examines effective and anomalous couplings within the context of an effective field theory. In this approach, the production cross section is constrained to be $ \sigma_{\gamma \mathrm{H}} γH production is performed with data from the CMS experiment at the LHC corresponding to an integrated luminosity of 138 fb-1 at a proton-proton center-of-mass collision energy of 13 TeV. The analysis focuses on the topology of a boosted Higgs boson recoiling against a high-energy photon. The final states of H→bb¯ and H→4ℓ are analyzed. This study examines effective HZγ and Hγγ anomalous couplings within the context of an effective field theory. In this approach, the production cross section is constrained to be σγH<16.4 fb at 95% confidence level (CL). Simultaneous constraints on four anomalous couplings involving HZγ and Hγγ are provided. Additionally, the production rate for H→4ℓ is examined to assess potential enhancements in the Yukawa couplings between light quarks and the Higgs boson. Assuming the standard model values for the Yukawa couplings of the bottom and top quarks, the following simultaneous constraints are obtained: κu=(0.0±1.5)×103, κd=(0.0-6.8+6.7)×102, κs=0-32+30, and κc=0.0-2.8+2.3. This rules out the hypothesis that up- or down-type quarks in the first or second generation have the same Yukawa couplings as those in the third generation, with a CL greater than 95%
ATLAS ITk Production Database use and tools
No full textThe ATLAS detector will undergo major upgrades before data-taking at the High Luminosity Large Hadron Collider will start in 2030. One of the main upgrades is a new radiation-hard inner tracking detector with a fast readout which is needed to cope with the high pile-up interaction rate (with up to 200 additional interactions per bunch crossing). Building this detector is an international effort and involves a large-scale manufacture of parts following a complex production flow across institutes. To maintain the tight production schedule and ensure the detector is build to specifications, continuous oversight of the build status is essential. For this purpose, a Production Database was developed which is a fully functional distributed data management system. It will be in use for the remaining years of construction and for 10 years of detector operation. The production database functionality and its usage is described in these proceedings
Evolution of the ATLAS TDAQ online software framework towards Phase-II upgrade: use of Kubernetes as an orchestrator of the ATLAS Event Filter computing farm
No full textThe ATLAS experiment at the LHC at CERN continuously evolves its TDAQ system to meet the challenges of new physics goals and technological advancements. As ATLAS prepares for the Phase-II Run 4 of the LHC, significant enhancements in the TDAQ Controls and Configuration (TDAQ-CC) tools have been designed to ensure efficient data collection, processing, and management. This abstract presents the evolution of ATLAS TDAQ-CC system leading up to Phase-II Run 4. As part of the evolution towards Phase-II, Kubernetes has been chosen to orchestrate the Event Filter (EF) farm. By leveraging Kubernetes, ATLAS can dynamically allocate computing resources, scale processing capacity in response to changing data taking conditions and ensure high availability of data processing services. The integration of the Kubernetes with the TDAQ Run Control framework enables perfect synchronisation between the experiment's data acquisition components and the computing infrastructure. We will discuss the architectural considerations and implementation challenges involved in Kubernetes integration with the ATLAS TDAQ-CC system. We will highlight the benefits of using Kubernetes as an EF farm orchestrator, including improved resource utilization, enhanced fault tolerance, and simplified deployment and management of data processing workflows. In addition, we will report on the extensive testing of Kubernetes that was conducted using a farm of 2500 servers within the experiment data taking environment, demonstrating its scalability and robustness in handling the demands of the ATLAS TDAQ system for Phase-II. The adoption of Kubernetes represents a significant step forward in the evolution of ATLAS TDAQ-CC system, aligning with industry best practices in container orchestration
RFQ test facility 2250
No full textA 750 MHz radiofrequency quadrupole (RFQ) is being conditioned at CERN’s 2250 test facility. This accelerator serves as a proof of principle for a linac-based carbon ion facility. This RFQ will accelerate protons, helium ions and fully stripped carbon ions to a final energy of 2.5 MeV/u, which is a step forward from the previous RFQ design focusing on protons alone. After the RFQ, the particles will be further accelerated in IH-type RF structures. In addition, CERN’s Accelerator Beam Physics group and the University of Sarajevo (UNSA) Physics Department propose a compact linear accelerator design for applied physics research. This collaboration serves as an example of how to transfer CERN knowledge and technology to societal applications. The accelerator, consisting of an ion source, a low-energy beam transport line, and a 0.5 MeV/u RFQ, is named the Sarajevo Ion Accelerator (SARAI). The SARAI source is due in the next months, and after commissioning, it will serve as an injector into the RFQ too. SARAI's main purpose is to conduct research, spanning from beam dynamics studies to material surface analysis
Visit by Professor Birgitta Wolff, Rector, University of Wuppertal, Germany
No full textVisit by Professor Birgitta Wolff, Rector, University of Wuppertal, Federal Republic of German
Angular analysis of decays
No full textAn angular analysis of decays is presented using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb. The analysis is performed in the region of the dilepton invariant mass squared of 1.1-6.0 GeV. In addition, a test of lepton flavour universality is performed by comparing the obtained angular observables with those measured in decays. In general, the angular observables are found to be consistent with the Standard Model expectations as well as with global analyses of other processes, where is either a muon or an electron. No sign of lepton-flavour-violating effects is observed.An angular analysis of B→ Kee decays is presented using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb. The analysis is performed in the region of the dilepton invariant mass squared of 1.1–6.0 GeV/c. In addition, a test of lepton flavour universality is performed by comparing the obtained angular observables with those measured in B→ Kμμ decays. In general, the angular observables are found to be consistent with the Standard Model expectations as well as with global analyses of other b → sℓℓ processes, where ℓ is either a muon or an electron. No sign of lepton-flavour-violating effects is observed.[graphic not available: see fulltext]An angular analysis of decays is presented using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb. The analysis is performed in the region of the dilepton invariant mass squared of 1.1-6.0 GeV. In addition, a test of lepton flavour universality is performed by comparing the obtained angular observables with those measured in decays. In general, the angular observables are found to be consistent with the Standard Model expectations as well as with global analyses of other processes, where is either a muon or an electron. No sign of lepton-flavour-violating effects is observed
Evaluation of pixel sensors produced with a commercial 150nm CMOS process for the CMS Phase-2 Upgrade
No full textThe CMS experiment will undergo a
major upgrade to prepare for the High-Luminosity phase of the LHC.
Within the context of this upgrade, studies on a novel passive sensor
production technique for hybrid pixel detectors were performed.
The sensors were produced using a commercial CMOS process
with a feature size of that enables the use of stitching to produce large sensors out of different sub-reticles of . This provides the
possibility to produce sensors larger than the size of a reticle of
while retaining the small feature sizes enabled
through projection lithography. Additionally, the use of commercial
production lines enables higher throughput and is potentially less
expensive with the possibility to process larger wafers than with contact lithography techniques, which is currently commonly used in High-Energy physics.
To evaluate this novel sensor production process, two large prototyping
campaigns were performed for the CMS Phase-2 Inner Tracker. This
includes the production of large sensors with a size of up to and a pixel pitch of . The sensors
were bump-bonded to CROC read-out chips and irradiated to a non-ionizing radiation dose of up to . Both, before and after the irradiation
campaign, the sensors were tested in test beam environments.
The prototyping campaigns have shown, that sensors produced with a commercial LFoundry CMOS process fulfill the performance requirements for CMS Phase-2 Inner Tracker and are a promising candidate, for current and future detectors. In this report, a summary of the prototyping campaign is presented, including the yield of the sensor production, the performance of the sensors and a comparison of their detection efficiency before and after irradiation
CMS jet measurements and constraints on PDFs and
No full textA selection of recent jet measurements in proton-proton collisionsfrom the CMS Collaboration at the CERN LHC is presented.Several experimental results targeting jet production are summarized, includingdifferential measurements of the inclusive jet cross section at center-of-massenergies of = 13 TeV and 5.02 TeV, and of the dijet cross sectionat = 13 TeV.The measurements are compared to state-of-the-art theoretical predictionsat next-to-next-to-leading-order accuracy in perturbative QCD, and the strong couplingconstant is extracted simultaneously with the parton distribution functions (PDFs)of the proton at 13 TeV.A further experimental handle on is provided by a measurement of jetazimuthal correlations.Finally, a novel measurement of the energy-energy correlators inside jets is outlined. These providean additional way of determining while also constituting useful observables forprobing phase spaces dominated by nonperturbative processes like hadronization and haveapplications in the context of Monte Carlo event generator tuning