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Analysis of the Thermal Annealing Regeneration Process of RPL Dosimeters for High Dose Levels
No full textThis work provides the analysis of two thermal
treatments for the annealing regeneration process of radio-
photoluminescent dosimeters (RPLDs) used in high-level dose
measurements. After regeneration, dosimeter sensitivity was
assessed through several irradiation campaigns, with doses reach-
ing up to 500 kGy using 60Co gamma radiation and X-rays with
an energy spectrum up to 100 keV. The regenerated dosimeters
exhibited good agreement, with deviations less than 10% up to
10 kGy. Fading effects were also monitored, and the proposed
thermal treatments had no significant impact on the decay rate
of the optical centers. Both annealed and pristine dosimeters
have shown negligible fading effects over 300 days, confirming
the stability of the optical centers
Parameter Shift Rule for Variational Photonic Quantum Circuit
No full textIn recent years, variational quantum algorithms (VQA) have been receiving a great deal of attention, demonstrating their applicability in a wide range of tasks and implementable even in the noisy quantum processors currently available [1]. A VQA is a hybrid quantum-classical algorithm where a problem is encoded in a cost function that can be efficiently evaluated on a parametric quantum device and the minimum represents the desired solution. A classical optimizer can then be used to tune the parameters of the quantum device in order to minimize the loss function and find the optimal solution (Fig. 1). In the field of quantum computing, one of the main promising platforms is based on the use of single photons and integrated photonic circuits since photons are a natural choice for transferring information and have different degree of freedom that can be to encode the information. Moreover the use of integrated photonic allow the realization of compact and table complex interferometers with a high number of control parameters. Even if there are few applications [2], [3], VQA with photonic platforms remains a relatively unexplored subject. One of the main problems is the application of the classical optimizer to the photonic platform since most of the algorithms are based on the estimation of the gradient of the cost function with the finite difference method but that can not be applied to a noisy apparatus
Advancing gravitational wave predictions from cosmological first-order phase transitions
No full textPhase transitions, in general, involve a nonzero spinodal temperature at which the potential barrier disappears. In some models of cosmological first-order phase transitions, supercooling is maintained until around the spinodal temperature, so the phase transition proceeds during the time when the potential barrier disappears rapidly. In this talk, I will discuss whether, in this circumstance, the phase transition is completed via bubbles or phase mixing driven by the growth of tachyonic modes. Based on our numerical simulations solving the Langevin equation, we conclude that the bubble nucleation picture is still valid even if the width and height of the potential barrier are smaller than the temperature scale. Therefore, the standard analysis based on bubble nucleation rate is applicable, assuming the bubble nucleation rate is properly calculated
Advancing gravitational wave predictions from cosmological first-order phase transitions
No full textExamples of GW from FOPT in BSM models and WallGo: I present three examples of BSM producing GW: one from SO(10) from the breaking chain (2506.07182), another from a first-order phase transition of the inflaton coupled to a dark sector (2412.17278) and the third one from reheating through particle production. As we know, uncertainties in the fundamental parameters affect the phase transition observables. I will present how predictions drastically change in these scenarios taking into account these uncertainties. I will present some results using WallGo and the limitations we have found using it
Advancing gravitational wave predictions from cosmological first-order phase transitions
No full textTerminal velocity of bubble walls in cosmological first-order phase transitions is a key parameter affecting both the primordial gravitational wave signal and baryon asymmetry production in electroweak baryogenesis. In this talk, I present recent results showing that, under local thermal equilibrium, pure hydrodynamic backreaction can lead to steady-state expansion, as confirmed by numerical simulations. However, this is not generic. Runaways are more common, as bubble walls often reach supersonic velocities before the fluid shell forms. To capture this effect, we extend analytical methods beyond local equilibrium and provide a criterion to identify physical detonations, with important consequences for cosmological observables
ITS3: the ALICE Inner Tracking System upgrade
No full textThe ALICE experiment at CERN is developing an upgrade to its vertexing detector in order to improve the impact parameter resolution at low transverse momenta, with a target timeline for installation during the third long shutdown of the LHC (2026–28). The concept consists in replacing the three innermost layers with wafer-scale monolithic active pixel sensors bent into truly cylindrical sensors wrapped around the beam pipe. The dramatic reduction in material budget (0.35% X to 0.07% X per layer), together with a thinner beam pipe (18 to 16.5 mm in radius) and a first layer closer to the interaction point (23 to 19 mm), are key features to increase the pointing resolution by at least a factor of 2 over all momenta [1]. This contribution provides an overview on the plans, challenges and status of the design and validation of the first wafer-scale silicon detector for high energy physics
Searches for electroweak production of supersymmetric particles with the ATLAS detector
No full textThe direct production of electroweak SUSY particles, including sleptons, charginos, and neutralinos, is a particularly interesting area with connections to dark matter and the naturalness of the Higgs mass. The small production cross-sections and challenging experimental signatures, often involving compressed spectra, lead to difficult searches. This talk will highlight the most recent results of searches performed by the ATLAS experiment for supersymmetric particles produced via electroweak processes, including analyses targeting small mass splittings between SUSY particles, and including both in R-parity-conserving and R-parity-violating scenarios. Recent results involving the combination of searches are also presented