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Search for dijet resonances with data scouting in proton-proton collisions at
No full textA search is presented for resonances decaying to dijet final states in proton-proton collisions at . This search, for narrow resonances with a mass between and , is performed using dijets that are reconstructed from calorimeter information in the trigger, in so-called data scouting, from data corresponding to an integrated luminosity of . The dijet mass spectra are well described by a smooth parameterization and no significant evidence for the production of new particles is observed. Generic upper limits are presented on the product of the cross section, the branching fraction, and the acceptance for narrow quark-quark, quark-gluon, and gluon-gluon resonances, and are compared to the predictions from a variety of models of narrow dijet resonance production. The upper limits at confidence level on the coupling strength of a dark matter mediator are presented as a function of the mediator mass. These limits are significantly more constraining than those previously published by CMS
Prospects of angular correlation studies of identified hadrons in the LHC Run 3 with the ALICE experiment
No full textThe study of angular correlations of identified hadrons makes it possible to understand the impact of different processes that contribute to the hadronization mechanism in heavy-ion collisions and small collision systems. Depending on the quark composition and the system properties, the angular correlations exhibit different shapes. The mechanism of hadron production is nonperturbative, and because of that, only phenomenological models can be used. Those models still fail to fully describe hadron production. In particular, angular correlations for like-sign baryons are not reproduced by the models. The upgraded ALICE detector and the new analysis framework allow for precise measurements of baryon angular correlations which provide stronger constraints on the hadronization mechanisms.The study of angular correlations of identified hadrons makes it possible to understand the impact of different processes that contribute to the hadronization mechanism in heavy-ion collisions and small collision systems. Depending on the quark composition and the system properties, the angular correlations exhibit different shapes. The mechanism of hadron production is non-perturbative, and because of that, only phenomenological models can be used. Those models still fail to fully describe hadron production. In particular, angular correlations for like-sign baryons are not reproduced by the models. The upgraded ALICE detector and the new analysis framework allow for precise measurements of baryon angular correlations which provide stronger constraints on the hadronization mechanisms
ALICE FoCal overview
No full textThe Forward Calorimeter (FoCal) is a new sub-detector in ALICE to be installed during the LHC Long Shutdown 3 for LHC Run 4. It consists of a highly-granular Si+W electromagnetic calorimeter combined with a conventional metal-scintillator hadronic calorimeter, covering a pseudorapidity interval of 3.2 : η : 5.8. The FoCal is optimised to measure various physics quantities in the forward region, allowing exploration of the gluon density in hadronic matter down to x ~ 10−6, thus providing insights into non-linear QCD evolution at the LHC. These proceedings introduce the FoCal physics program and its corresponding performance. Additionally, the performance of the FoCal prototype will be presented.The Forward Calorimeter (FoCal) is a new sub-detector in ALICE to be installed during the LHC Long Shutdown 3 for LHC Run 4. It consists of a highly-granular Si+W electromagnetic calorimeter combined with a conventional metal-scintillator hadronic calorimeter, covering a pseudorapidity interval of . The FoCal is optimised to measure various physics quantities in the forward region, allowing exploration of the gluon density in hadronic matter down to , thus providing insights into non-linear QCD evolution at the LHC. These proceedings introduce the FoCal physics program and its corresponding performance. Additionally, the performance of the FoCal prototype will be presented
The ITS3 detector and physics reach of the LS3 ALICE Upgrade
No full textDuring Large Hadron Collider (LHC) Long Shutdown 3 (LS3) (2026-30), the ALICE experiment is replacing its inner-most three tracking layers by a new detector, Inner Tracking System 3. It will be based on newly developed wafer-scale monolithic active pixel sensors, which are bent into truly cylindrical layers and held in place by light mechanics made from carbon foam. Unprecedented low values of material budget (per layer) and closeness to interaction point (19 mm) lead to a factor two improvement in pointing resolutions from very low pT (O(100MeV/c)), achieving, for example, 20 µm and 15 µm in the transversal and longitudinal directions, respectively, for 1 GeV/c primary charged pions. After a successful R&D phase 2019-2023, which demonstrated the feasibility of this innovational detector, the final sensor and mechanics are being developed. This contribution briefly reviews the conceptual design and the main R&D achievements, as well as the current activities and road to completion and installation. It concludes with a projection of the improved physics performance, in particular for heavy-flavour hadrons, as well as for thermal dielectrons, that will come into reach with this new detector installed.During Large Hadron Collider (LHC) Long Shutdown 3 (LS3) (2026-28), the ALICE experiment is replacing its inner-most three tracking layers by a new detector, Inner Tracking System 3. It will be based on newly developed wafer-scale monolithic active pixel sensors, which are bent into truly cylindrical layers and held in place by light mechanics made from carbon foam. Unprecedented low values of material budget (per layer) and closeness to interaction point (19 mm) lead to a factor two improvement in pointing resolutions from very low (O(100MeV/)), achieving, for example, 20 m and 15 m in the transversal and longitudinal directions, respectively, for 1 GeV/c primary charged pions. After a successful R&D phase 2019-2023, which demonstrated the feasibility of this innovational detector, the final sensor and mechanics are being developed right now. This contribution will briefly review the conceptual design and the main R&D achievements, as well as the current activities and road to completion and installation. It concludes with a projection of the improved physics performance, in particular for heavy-flavour hadrons, as well as for thermal dielectrons, that will come into reach with this new detector installed
Sparks! Connect - CERN Innovation for Urban Futures
No full textSparks! Connect workshop hosts a specialised audience in the field of urban technologies and planning, allowing them to meet CERN staff specialised in core technologies linked to accelerators, detectors and computing, exploring opportunities for the transfer of CERN’s technology and know-how in their field
