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Multi-fragment decays of 129 Xe, 197 Au, and 238 U projectiles in collisions with Be, C, Al, Cu, In, Au, and U targets at energies between E/A = 400 MeV and 1000 MeV have been studied with the ALADIN forward-spectrometer at SIS. By adding an array of 84 SiCsI(Tl) telescopes the solid-angle coverage of the setup was extended to θ lab = 16 • . This permitted the complete detection of fragments from the projectile-spectator source.The dominant feature of the systematic set of data is the Z bound universality that is obeyed by the fragment multiplicities and correlations. These observables are invariant with respect to the entrance channel if plotted as a function of Z bound , where Z bound is the sum of the atomic numbers Z i of all projectile fragments with Z i ≥ 2. No significant dependence on the bombarding energy nor on the target mass is observed. The dependence of the fragment multiplicity on the projectile mass follows a linear scaling law.The reasons for and the limits of the observed universality of spectator fragmentation are explored within the realm of the available data and with model studies. It is found that the universal properties should persist up to much higher bombarding energies than explored in this work and that they are consistent with universal features exhibited by the intranuclear cascade and statistical multifragmentation models.

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Africa is one of the most vulnerable continents to climate change. In the upcoming decades the occurrence of longer, hotter and more frequent heat waves could have a strong impact on human mortality and crop production. Here, by applying the heat wave magnitude index daily to temperature reanalysis data, we quantify the magnitude and the spatial extent of the most extreme heat waves experienced in Africa between 1979 and October 2015 across different seasons. Results show that in the recent years Africa experienced hotter, longer and more extent heat waves than in the last two decades of the 20th century. In the future, 50% of regional climateprojections suggest that heat waves that are unusual under present climate conditions will occur on a regular basis by 2040 under the most severe IPCC AR5 scenario (i.e. RCP8.5).

Isotopic effects in the fragmentation of excited target residues following collisions of 12C on (112,124)Sn at incident energies of 300 and 600 MeV per nucleon were studied with the INDRA 4pi detector. The measured yield ratios for light particles and fragments with atomic number Z < or = 5 obey the exponential law of isotopic scaling. The deduced scaling parameters decrease strongly with increasing centrality to values smaller than 50% of those obtained for the peripheral event groups. Symmetry-term coefficients, deduced from these data within the statistical description of isotopic scaling, are near gamma = 25 MeV for peripheral and gamma < 15 MeV for central collisions.

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Multifragmentation has been measured for I97 Au+ 197 Au collisions at El A =100, 250, and 400 MeV. The mean fragment multiplicity increases monotonically with the charged particle multiplicity at El A =100 MeV, but decreases for central collisions with incident energy, consistent with the onset of nuclear vaporization. Molecular dynamics calculations follow some trends but underpredict the observed fragment multiplicities. Including the statistical decay of excited residues improves the agreement for peripheral collisions but worsens it for central collisions. PACS numbers: 25.70.Pq, 25.70.GhHighly excited systems can be formed during energetic nucleus-nucleus collisions, which expand due to thermal pressure [1,2] or via dynamical compression-decompression cycles [3]. For systems which expand to low densities where bulk nuclear matter is thermodynamically unstable, the growth of density fluctuations may favor multifragment disintegrations [4][5][6], and such disintegrations have been observed [7][8][9][10][11][12]. While definitive interpretations are premature, calculations predict that the onset of multifragmentation and the transition from multifragmentation into vaporization may be sensitive to the low density equation of state [2,13] and the liquid-gas phase transition of nuclear matter [14][15][16][17].The incident energy dependence of multifragmentation has been recently explored for 36 Ar+ 197 Au collisions between £7. 4=35 and 110 MeV [7]. These investigations reveal large fragment multiplicities for central collisions, which increase monotonically with incident energy. Over a broader range of incident energies, however, calculations predict a maximum in the fragment multiplicity for central collisions at El A ~ 100 MeV [18], and decreasing multiplicities thereafter, consistent with the onset of nuclear vaporization [4,5].

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