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Innovazione Aperta e tutela della Proprietà Intellettuale
No full text<p>Lezione tenuta drante il corso "Il trasferimento tecnologico dell'INFN" che riguarda l'innovazione aperta e la getione della Proprietà Intellettuale</p>
Low cloud response to aerosol-radiation-cloud interactions: Idealized WRF numerical experiments for EUREC4A project
No full text<p>Aerosols significantly affect cloud microphysics and energy budget in different ways. The contribution of the direct, semi-direct, and indirect effects of aerosols on radiation are here investigated over the North Atlantic tropical ocean under different aerosol loadings. The Weather Research and Forecasting Model is used to perform a set of numerical idealized experiments, which are forced with prescribed aerosol profiles. We evaluate the effects of aerosols on modeled shallow clouds and surface radiative budget. The results indicate that large aerosol loadings are associated with enhanced cloudiness and reduced precipitation. While the change in rainfall is mainly due to the larger number of smaller droplets, the change in cloudiness is attributed to the effects of absorbing aerosols, mainly dust particles, which are responsible for a rise of temperature that feeds back onto specific humidity. As in the boundary layer the increase of moisture dominates, the net effect is a higher relative humidity, which favors the formation of thin low non-precipitating clouds. The feedback accounts for a dynamical change in the lower troposphere: shortwave radiation absorption increases temperature at the top of the marine atmospheric boundary-layer and reduces entrainment of warm and dry air, increasing low level moisture content. Despite the overall increase in cloudiness, daytime cloud cover is reduced. The semi-direct effect of aerosols on clouds results in a warming of the surface, opposite to the indirect effect.</p>
Do black holes remember what they are made of?
No full textWe study the ringdown signal of black holes formed in prompt-collapse binary neutron star mergers. We analyze data from 47 numerical relativity simulations. We show that the and multipoles of the gravitational wave signal are well fitted by decaying damped exponentials, as predicted by black-hole perturbation theory. We show that the ratio of the amplitude in the two modes depends on the progenitor binary mass ratio q and reduced tidal parameter . Unfortunately, the numerical uncertainty in our data is too large to fully quantify this dependency. If confirmed, these results will enable novel tests of general relativity in the presence of matter with next-generation gravitational-wave observatories
B meson production in Pb+Pb at 5.02 ATeV at LHC: Estimating the diffusion coefficient in the infinite mass limit
No full textIn the last decade a Quasi-Particle Model (QPM) has been developed to study charm quark dynamics in ultra-relativistic heavy-ion collisions supplying a satisfactory description of the main observables for D meson and providing an estimate of the space-diffusion coefficient Ds(T) from the phenomenology. In this paper, we extend the approach to bottom quarks describing their propagation in the quark-gluon plasma within an event-by-event full Boltzmann transport approach followed by a coalescence plus fragmentation hadronization. We find that QPM approach is able to correctly predict the first available data on RAA(pT) and v2(pT) of single-electron from B decays without any parameter modification w.r.t. the charm. We show also predictions for centralities where data are not yet available for both v2(pT) and v3(pT). Moreover, we discuss the significant breaking of the expected scaling of the thermalization time τth with MQ/T, discussing the evolution with mass of Ds(T) to better assess the comparison to lQCD calculations. We find that at T=Tc charm quark Ds(T) is about a factor of 2 larger than the asymptotic value for M→∞, while bottom Ds(T) is only a 20% higher. This implies a Ds(T) which is consistent within the current uncertainty to the most recent lattice QCD calculations with dynamical quarks for M→∞
Thermodynamics of black holes with probe D-branes
No full textUnderstanding how the thermodynamic properties of a black hole are modified when probed by D-branes is an important problem in AdS/CFT. This work focuses on a recently proposed black hole/D3-brane system in AdS×S, which is dual to four-dimensional = 4 SYM in the presence of a two-dimensional surface defect. The Laplace transform that extracts the asymptotic growth of states in this defect CFT naturally defines a thermodynamic approach in the gravitational side of the duality for which charges and entropy are real. Studying the superconformal defect index in a large-charge expansion for all values of N, we compute the leading correction to the entropy of the combined system, which matches precisely with its gravity counterpart
Papera Quantistica
Get PDF<p>Origami e flexagoni per illustrare il contenuto in quark della materia ordinaria. Target Eta`: Bambini dai 6 ai 10 anni.</p>
Determination of the moments of the proton charge density
No full textA global analysis of proton electric form factor experimental data from Rosenbluth separation and low squared four-momentum transfer experiments is discussed for the evaluation of the spatial moments of the proton charge density based on the recently published integral method [Hoballah , Phys. Lett. B 808, 135669 (2020)]. Specific attention is paid to the evaluation of the systematic errors of the method, particularly the sensitivity to the choice of the mathematical expression of the form factor fitting function. Within this comprehensive analysis of proton electric form factor data, the moments of the proton charge density are determined for integer order moments, particularly: 〈r2〉=0.694(09)stat(16)sysfm2, 〈r3〉=0.870(46)stat(80)sysfm3, and 〈r4〉=1.47(25)stat(45)statfm4
GPU porting of a Boltzmann code. Description of the strategy for the implementation.
Get PDF<p>We propose to offload to GPUs some of the most expensive routines in the Boltzmann code CLASS. The motivation is the high computational expense associated to the production of large training datasets for cosmological Cosmic Microwave Background (CMB) angular power spectrum emulators, especially in the context of non-standard (beyond-ΛCDM) cosmological models.</p>
A search for \upmu ^+ \rightarrow \textrm{e}^+ \upgamma with the first dataset of the MEG II experiment
No full textThe MEG II experiment, based at the Paul Scherrer Institut in Switzerland, reports the result of a search for the decay \upmu ^+ \rightarrow {\textrm{e}}^+ \upgamma from data taken in the first physics run in 2021. No excess of events over the expected background is observed, yielding an upper limit on the branching ratio of {\mathcal {B}} (\upmu ^+ \rightarrow {\textrm{e}}^+ \upgamma ) < 7.5 \times 10^{-13} (90% CL). The combination of this result and the limit obtained by MEG gives {\mathcal {B}} (\upmu ^+ \rightarrow {\textrm{e}}^+ \upgamma ) < 3.1 \times 10^{-13} (90% CL), which is the most stringent limit to date. A ten-fold larger sample of data is being collected during the years 2022–2023, and data-taking will continue in the coming years
Measurement of the ee → π cross sections from = 2.000 to 3.080 GeV
No full textBased on ee collision data collected at center-of-mass energies from 2.000 to 3.080 GeV by the BESIII detector at the BEPCII collider, a partial wave analysis is performed for the process ee → π. The results allow the Born cross sections of the process ee → π, as well as its subprocesses ee → K(892) and (1430) to be measured. The Born cross sections for ee → π are consistent with previous measurements by BaBar, but with substantially improved precision. The Born cross section lineshape of the process eeK(892) is consistent with a vector meson state around 2.2 GeV with a significance of 3.2σ. A Breit-Wigner fit determines its mass as M = (2164.7 ± 9.1 ± 3.1) MeV/c and its width as Γ = (32.4 ± 21.0 ± 1.8) MeV.[graphic not available: see fulltext