Tradition and modernity in the mediterranean cities. The tunisian cities: Tunis, Kairouan, Tozeur, Nefta.

L’articolo fa un confronto tra le differenti forme urbane delle città del Nord Africa, in particolare quelle della Tunisia (Tunisi, Kairouan, Tozeur, Nefta). Tali città, distribuite tra il Nord ed il Sud del paese, esprimono, nelle loro medine, l’identità della forma urbana e ne dichiarano la modernità lungo i loro bordi. Tunisi, posta tra due laghi, costruisce la sua modernità con la città coloniale che, anche se con linguaggi diversi, evidenzia i temi del Mediterraneo. La città di Kairouan mantiene la sua identità nella grande moschea, luogo centrale di organizzazione urbana. Le città d’oasi, come Tozeur e Nefta, esprimono il loro rapporto col paesaggio ed evidenziano con le loro architetture i materiali usati

Measurements of inclusive and differential cross sections for the Higgs boson production and decay to four-leptons in proton-proton collisions at s \sqrt{s} = 13 TeV

Measurements of the inclusive and differential fiducial cross sections for the Higgs boson production in the H → ZZ → 4ℓ (ℓ = e, μ) decay channel are presented. The results are obtained from the analysis of proton-proton collision data recorded by the CMS experiment at the CERN LHC at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb$^{−1}$. The measured inclusive fiducial cross section is 2.73 ± 0.26 fb, in agreement with the standard model expectation of 2.86 ± 0.1 fb. Differential cross sections are measured as a function of several kinematic observables sensitive to the Higgs boson production and decay to four leptons. A set of double-differential measurements is also performed, yielding a comprehensive characterization of the four leptons final state. Constraints on the Higgs boson trilinear coupling and on the bottom and charm quark coupling modifiers are derived from its transverse momentum distribution. All results are consistent with theoretical predictions from the standard model

Search for the lepton-flavor violating decay of the Higgs boson and additional Higgs bosons in the eμ\mu final state in proton-proton collisions at s\sqrt{s} = 13 TeV

A search for the lepton-flavor violating decay of the Higgs boson and potential additional Higgs bosons with a mass in the range 110-160 GeV to an e$^{\pm}\mu^{\mp}$ pair is presented. The search is performed with a proton-proton collision data set at a center-of-mass energy of 13 TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138 fb$^{-1}$. No excess is observed for the Higgs boson. The observed (expected) upper limit on the e$^{\pm}\mu^{\mp}$ branching fraction for it is determined to be 4.4 (4.7) $\times$ 10$^{-5}$ at 95% confidence level, the most stringent limit set thus far from direct searches. The largest excess of events over the expected background in the full mass range of the search is observed at an e$^{\pm}\mu^{\mp}$ invariant mass of approximately 146 GeV with a local (global) significance of 3.8 (2.8) standard deviations

Observation of the rare decay of the η\eta meson to four muons

A search for the rare $\eta$$\to$$\mu^+\mu^-\mu^+\mu^-$ double-Dalitz decay is performed using a sample of proton-proton collisions, collected by the CMS experiment at the CERN LHC with high-rate muon triggers in 2017-2018 and corresponding to an integrated luminosity of 101 fb$^{-1}$. A signal having a statistical significance well in excess of 5 standard deviations is observed. Using the \emm decay as normalization, the branching fraction $\mathcal{B}($η$\to \mu^+\mu^-\mu^+\mu^-)$ = ( 5.0 $\pm$ 0.8 (stat) $\pm$ 0.7 (syst) $\pm$ 0.7 $\mathcal{B}_{2\mu}$ ) $\times$ 10$^{-9}$ is measured, where the last term is the uncertainty in the normalization channel branching fraction. This is the first measurement of this branching fraction and is found to be in agreement with theoretical predictions