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Charm physics results from ATLAS experiment
No full textATLAS experiment, while not being a dedicated detector for flavour physics, provides great opportunities for studying beauty and charm hadron production and spectroscopy when using their decays with muons in final state. This presentation will cover the recent results on production of charmonium states and open charm hadrons as well as searches for exotic states in charm sector
Group photo of the "ALICE 3 Days: May 2025"
No full text"ALICE 3" Days: May 2025 is devoted to a general overview of the ALICE 3 detector design and scoping, and to updates on the plans and
Measurement of branching fraction with the KLOE detector
No full textWe present a measurement of the radiative decay using 82 million mesons produced in process at the Frascati -factory DANE. From the data analysis signal events are observed. By normalising the signal to the well-known decay the branching fraction is measured to be . This result agrees with a preliminary KLOE measurement, but is twice smaller than the present world average. Results for are also presented and compared with latest theory predictions
Advanced Designs for Enhanced Thermo-Magnetic Stability in High Jc Nb3Sn Wires
No full textThe DT design provides high Jc through uniform tin distribution, while the DB design enhances mechanical strength and thermal stability. The hybrid design, known as the Distributed Barrier Strand (DBS), balances these properties, significantly improving thermo-magnetic stability while maintaining high Jc. The wires were fabricated using the internal tin process and underwent a multi-stage heat treatment to form the Nb3Sn phase. Evaluations of various designs in terms of critical current density (Jc), thermo-magnetic stability, strain tolerance, and mechanical properties revealed that the DBS hybrid design exhibited higher stability and performance compared to the individual DT and DB designs. This research offers key insights into the design and fabrication of Nb3Sn superconducting wires and has important implications for high-performance applications
Result of Powering and Field Measurements on the GaToroid Demonstrator
No full textGaToroid is a novel idea of a steady-state, toroidal magnet that directs multiple charged particle beams for hadron or electron therapy without rotating parts or magnet ramping. GaToroid has the potential of conformal radiotherapy with a configuration that can be simpler and lighter than conventional rotating gantries, also offering FLASH capability well beyond what is presently possible. A crucial feature of the magnet is the field profile, which is optimized to maximize acceptance (large field area) and beam transmission (good field homogeneity). We have built and tested a 1:3 scale Nb-Ti demonstrator of the proton GaToroid to verify performance, field profile and quench protection. Here we describe the specific features of the demonstrator cable, coil and magnet, and report the main test results. The magnet reached critical current with no training, the field profile is within 1% of the expected values, and quench detection and protection are well understood, thus proving that this magnet technology is ripe for a full-size system demonstration
Conceptual Design of BOND: A 14 T Dipole for FCC-Hh
No full textHigh Field NbSn superconducting magnets are a core technology to increase the collision energy of particle accelerators beyond that of the Large Hadron Collider (LHC). In the framework of the conceptual design of a Future Circular Collider (FCC), or an energy upgrade of the LHC, different magnet layouts are being considered within the so-called High Field Magnet program. The target for all these designs is to provide a dipole field of in a aperture. Cos-theta, block-type and common-coil magnets are explored. Following the successful test of the Racetrack Model Magnet (RMM) at CERN, which reached 16.5 T in a closed cavity, this paper details a block-type design made of 2 double-layers coils with flared-ends. The key challenges are addressed to provide an attractive solution for an accelerator type dipole aiming at a short-sample limit of using available NbSn strand. A detailed 2D electromagnetic and mechanical analysis is presented for a single aperture demonstrator. In addition, the preliminary electromagnetic optimization for the final double aperture magnet is introduced
Design of Superconducting Magnetic Energy Storage (SMES) for Waterborne Applications
No full textThe shift from fossil fuel to electric based propulsion in the waterborne transport sector has been sped up by recent policies aiming to reduce the sector emissions. This trend creates highly electrified vessels, with needs for energy storage systems (ESS) to satisfy the power demand affordably and to increase the on-board grid reliability and efficiency. Initial industry efforts have been put in the study and integration of high energy density ESS solutions, mainly electrochemical batteries. However, other innovative ESS, with different capabilities, have not been yet fully addressed. It is the case of Fast Response Energy Storage Systems (FRESS), such as Supercapacitors, Flywheels, or Superconducting Magnetic Energy Storage (SMES) devices. The EU granted project, POwer StoragE IN D OceaN (POSEIDON) will undertake the necessary activities for the marinization of the three mentioned FRESS. This study presents the design process followed in the POSEIDON project for the definition of an SMES suitable for maritime operation. First, the boundary conditions imposed by the marine environment, and the potential on-board applications of the SMES will be established. Next, the technological options: superconducting material, cooling system, coil fabrication and magnet topology which have been selected for this specific system will be presented
Lower limits on the Higgs boson lifetime via off-shell decays into final states with the ATLAS detector.
No full textThis article presents an analysis of the off-shell Higgs boson production rate in the decay mode and interprets the results in terms of the Higgs boson’s lifetime---or equivalently, its total width---focusing on final states in which both bosons decay leptonically. The study uses proton–proton collision data corresponding to an integrated luminosity of 140 , recorded at a center-of-mass energy of 13 TeV by the ATLAS experiment at the LHC. The observations are consistent with predictions from the Standard Model. A 95% CL upper limit is placed on the off-shell Higgs production rate at 3.4 times the Standard Model expectation, with an expected limit of 4.4. By combining these findings with measurements of the on-shell Higgs production rate in identical final states, a 95% CL lower bound on the Higgs boson lifetime is set at 5.0 s, with an expected lower bound of 3.8 s
Search for heavy H and Z resonances with a b quark pair final state in proton-proton collisions at sqrt(s) = 13 TeV
No full textA search for heavy resonances decaying into a H or Z boson and a photon, with the H and Z bosons decaying to a pair of bottom quarks (b) is presented. The analysis is performed in proton-proton collision data at collected by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of . The analyzed events include a photon and a massive, large-radius jet with a significant Lorentz boost containing the b system and is identified as a candidate for the H or Z boson. An advanced flavor tagging algorithm based on the transformer architecture is used to classify jets into 314 categories based on their substructures, and it is employed to efficiently identify and select H and Z boson candidate jets decaying into b, suppressing background. A set of parametric functions is used to fit the photon-jet invariant mass spectrum and to extract potential signals. No significant excess above standard model expectations is observed. The results are interpreted as upper limits on the product of the production cross section and branching fraction for narrow spin-1 H resonances and for spin-0 Z resonances of various widths. These limits are the most stringent to date