Pier Giorgio De Sanctis Lucentini

The equal load-sharing model of cascade failures in power grids

Electric power-systems are one of the most important critical infrastructures. In recent years, they have been exposed to extreme stress due to the increasing power demand, the introduction of distributed renewable energy sources, and the development of extensive interconnections. We investigate the phenomenon of abrupt breakdown of an electric power-system under two scenarios: load growth (mimicking the ever-increasing customer demand) and power fluctuations (mimicking the effects of renewable sources). Our results indicate that increasing the system size causes breakdowns to become more abrupt; in fact, mapping the system to a solvable statistical-physics model indicates the occurrence of a first order transition in the large size limit. Such an enhancement for the systemic risk failures (black-outs) with increasing network size is an effect that should be considered in the current projects aiming to integrate national power-grids into “super-grids”.

The meaning of the UHECR Hot Spots - A light nuclei nearby astronomy

In this paper we review all the up-to-date Ultra High Energy Cosmic Ray (UHECR) events reported by AUGER, the Telescope Array (TA) and AGASA in common coordinate maps. We also confirm our earliest (2008–2013) model, where UHECRs mostly comprise light nuclei (namely He, Be, B), which explains the Virgo absence and confirms M82 as the main source for the Northern TA Hot Spot. Many more sources, such as NGC253 and several galactic sources, are possible candidates for most of the 376 UHECR events. Several correlated maps, already considered in recent years, are reported to show all the events, with their statistical correlation values.

A Mean Field Model of Coupled Cascades in Flow Networks

We introduce an analytical model of cascading behavior of interdependent networks under stressing conditions and find evidence of abrupt breakdown phenomena. Our results indicate that coupling several infrastructures can diminish the impact of small cascades at the cost of increasing system wide ones. As a consequence, the enhancement of the systemic risk failures with increasing network size, represents an effect to be accounted while planning projects aiming to integrate national networks into “super-networks”.

Where are the Ultra High Energy Cosmic Ray (UHECR) originated

We consider the recent results on UHECR (Ultra High Energy Cosmic Ray) composition and their distribution in the sky from ten EeV energy (the dipole anisotropy) up to the highest UHECR energies and their clustering maps: UHECR have been found mostly made by light and lightest nuclei. We summarized the arguments that favor a few localized nearby extragalactic sources for most UHECR as CenA, NG 253, M82. We comment also on the possible partial role of a few remarkable galactic UHECR sources. Finally we revive the eventual role of a relic neutrino eV mass in dark hot halo (hit by ZeV neutrinos) to explain the new UHECR clustering events centered around a very far cosmic AGN sources as 3C 454.

May GWs signals by BH-BH merging be associated with any

The Gravitational Wave (GW) events GW150914, GW151226, GW170104 detected by LIGO were a record of Black Hole binary merging system (BH-BH) very probably in nearly empty or a vacuum space; such a kind of events will be mostly with no baryon mass (plasma or dense masses) and therefore mute or blind in any correlated gamma band. By best GW triangulation (as soon as Virgo has been active) their position will be widely located only in a smeared sky (tens or hundred square degree) because of the absence of any correlated spherically-symmetric electromagnetic signal whose photons might be pointing to the exact sources in the sky. If the GWs events might be born inside a globular cluster, a star forming region or along a spiral AGN accretion disk their additional accreting mass may be the needed baryon load to explode and shine: in those dense places BH-BH collapse may also offer an optical-X-g afterglow via their baryon lightening and photon tracks. However these peculiar orbiting or multi-body systems should also imprint their presence in the inner Kepler period as well as in a perturbed GW signature by unusual time structure. Moreover any Black Hole active (by a relic jets and-or an accretion disk) might shine and blaze during the collapse with a BH by its jet too: however these beams, being extremely collimated, are rarely pointing toward us during the same brief GWs emission. Only very nearby (tens Mpc) BH-Neutron Star (NS) or NS????NS cannibal merging might be associated with a desired, visible and correlated spherical NS explosion (kilonova one); these rare explosion and their GWs might therefore be localized by photon tracks. But they are lower mass system and they require much lower threshold or just nearer distances. Because of such nearer cosmic volumes (tens Mpc) and because of the very anisotropic beamed GRB associated, these kilohertz event are possibly still very rare and unexpected in gamma sky (even with LIGO Virgo array sky narrow view). However the very exceptional GW170817 GRB170817a event last August 2017 it took place and it was related to a very first NS????NS collapse in a SN-kilonova spherical explosion. This event had been recorded both by its few (day and months) optical transient but as well as by its weak, prompt, short, GRB, two seconds later the same LIGO-Virgo detection. The GRB170817a gamma, X, radio signature it was exceptional in many features and one may wonder and he may ask if it was really correlated to the GWs. Its unique values (softer, weaker, the most near one ) made GRB170817a very possibly an off-axis jet detection. However there are solid arguments that suggest that such a GRB are not just blazing within a collimated beam jet but that they are also shining in a wider spread gamma equatorial disk blazing, orthogonal to the jet itself. In a few words we were observing the event not along its jet but mostly orthogonal to it. This GRB170817a geometry may better explain the otherwise unexpected beamed to us event. In this paper therefore we summarize the astrophysical and the cosmological signature of such a long desired multiple astronomy.The Gravitational Wave (GW) events GW150914, GW151226, GW170104 detected by LIGO were a record of Black Hole binary merging system (BH-BH) very probably in nearly empty or a vacuum space; such a kind of events will be mostly with no baryon mass (plasma or dense masses) and therefore mute or blind in any correlated gamma band. If the GWs events might be born inside a globular cluster, a star forming region or along a spiral AGN accretion disk their additional accreting mass may be the needed baryon load to explode and shine: in those dense places. BH BH collapse may also offer an optical X and gamma afterglow via their baryon lightening and photon tracks. Only very nearby (tens Mpc) BH Neutron Star (NS) or NS NS cannibal merging might be guaranteed and associated also with a desired, visible and correlated spherical NS explosion (kilonova one); they require much lower threshold or just nearer distances. Indeed such a very exceptional GW170817 GRB170817a event occurred last August 2017; it took place and it was related to a very first NS NS collapse in a SN kilonova spherical explosion. The GRB170817a gamma, X, radio signature it was exceptional in many features . Its unique values (softer, weaker, the most near and long life one) made GRB170817a very possibly an off-axis jet detection. However there are solid arguments that suggest that such a GRB are not just blazing within a collimated beam jet but that they are also shining in a wider spread gamma equatorial disk blazing, orthogonal to the jet itself. In a few words we were observing the event not along its jet but mostly orthogonal to it. This GRB170817a geometry may better explain the otherwise unexpected beamed to us event. In this paper therefore we summarize the astrophysical and the cosmological signature of such a long desired multiple astronomy.

\gamma

The Sun albedo of Cosmic Rays (CRs) at GeVs energy has been discovered recently by the FERMI satellite. They are traces of atmospheric CRs hitting solar atmosphere and reflecting skimming gamma photons. Even if relevant for astrophysics, as being a trace of atmospheric solar CR noises they cannot offer any signal of neutrino astronomy. On the contrary, the Moon with no atmosphere, may become soon a novel filtering calorimeter and an amplifier of energetic muon astronomical neutrinos (at TeV up to hundred TeVs energy); these lepton tracks leave an imprint in their beta decay while in flight to Earth. Their TeV electron air-shower are among the main signals. Also, a more energetic, but more rare, PeV up to EeV tau lunar neutrino events may be escaping as a tau lepton from the Moon: τ PeV secondaries, then, may be shining on Earth’s atmosphere in lunar shadows in a surprising way. One or a few gamma air-shower events inside the Moon shadows may occur each year in near future Cherenkov telescope array (CTA) o...