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Abstract Cadmium telluride (CdTe) semiconductor thin films were obtained by thermal vacuum evaporation (TVE) on optical glass substrates. The optical characterizations of CdTe thin films were made by spectroscopic ellipsometry (SE) and optical spectrophotometry. The optical constants (refractive indices and extinction coefficients) were obtained for CdTe thin films of different thicknesses. High absorption coefficients of order 105 cm−1 and suitable optical bandgaps values of 1.5 eV were obtained. The surface morphology of the obtained films was investigated by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) techniques. The influences of post-deposition thermal treatment on CdTe morphological properties were discussed. The current–voltage characteristics of CdTe films were recorded at temperatures in the range 150–280 K. An electrical analysis of the conduction mechanisms specific for different voltage ranges was also employed.

AbstractGlobal climate change is expected to further raise the frequency and severity of extreme events, such as droughts. The effects of extreme droughts on trees are difficult to disentangle given the inherent complexity of drought events (frequency, severity, duration, and timing during the growing season). Besides, drought effects might be modulated by trees’ phenotypic variability, which is, in turn, affected by long‐term local selective pressures and management legacies. Here we investigated the magnitude and the temporal changes of tree‐level resilience (i.e., resistance, recovery, and resilience) to extreme droughts. Moreover, we assessed the tree‐, site‐, and drought‐related factors and their interactions driving the tree‐level resilience to extreme droughts. We used a tree‐ring network of the widely distributed Scots pine (Pinus sylvestris) along a 2,800 km latitudinal gradient from southern Spain to northern Germany. We found that the resilience to extreme drought decreased in mid‐elevation and low productivity sites from 1980–1999 to 2000–2011 likely due to more frequent and severe droughts in the later period. Our study showed that the impact of drought on tree‐level resilience was not dependent on its latitudinal location, but rather on the type of sites trees were growing at and on their growth performances (i.e., magnitude and variability of growth) during the predrought period. We found significant interactive effects between drought duration and tree growth prior to drought, suggesting that Scots pine trees with higher magnitude and variability of growth in the long term are more vulnerable to long and severe droughts. Moreover, our results indicate that Scots pine trees that experienced more frequent droughts over the long‐term were less resistant to extreme droughts. We, therefore, conclude that the physiological resilience to extreme droughts might be constrained by their growth prior to drought, and that more frequent and longer drought periods may overstrain their potential for acclimation.

Abstract Inclusive J/ψ production is studied in minimum-bias proton-proton collisions at a centre-of-mass energy of $$ \sqrt{s} $$ s = 5.02 TeV by ALICE at the CERN LHC. The measurement is performed at mid-rapidity (|y| < 0.9) in the dielectron decay channel down to zero transverse momentum p T, using a data sample corresponding to an integrated luminosity of L int = 19.4 ± 0.4 nb −1. The measured p T-integrated inclusive J/ψ production cross sec- tion is dσ/dy = 5.64 ± 0.22(stat.) ± 0.33(syst.) ± 0.12(lumi.) μb. The p T-differential cross section d2 σ/dp Tdy is measured in the p T range 0–10 GeV/c and compared with state-of- the-art QCD calculations. The J/ψ 〈p T〉 and $$ \left\langle {p}_{\mathrm{T}}^2\right\rangle $$ p T 2 are extracted and compared with results obtained at other collision energies.