Search results for "UHE"

Tra mito e modello. Le cattedrali normanne nell'architettura religiosa del Cinquecento in Italia meridionale

2021

Talora ammantata da un alone mitico e sempre celebrata dalla storiografia di età moderna, la fondazione delle cattedrali al tempo della dominazione normanna costituisce per l’architettura religiosa in Sicilia un vero e proprio anno zero. Il primato nell’ambito della tipologia basilicale, per un verso, e il configurarsi come luoghi di attualità operativa, per altro verso, hanno fatto delle stesse i termini di riferimento privilegiati per l’architettura religiosa al principio dell’età moderna. Ciò si osserva, in particolare, in un’ampia e variegata casistica di chiese realizzate nel corso del XVI secolo, che ripropongono e reinterpretano temi compositivi e spaziali propri delle suddette catte…

The Process of CEO Dismissal: An Exploratory study

2018

The decision to change the CEO is one of the most important decisions of the Board of Directors in a company. This study increases understanding of the process that leads to a Board’s decision to dismiss the CEO under conditions of poor performance, and of the meaning of attributions in CEO dismissal. The role of the Chair of the Board in this process is also explored. An exploratory, empirical study concerning nine CEO dismissal processes is conducted based on open-ended interviews with seven Chairpersons of the Board. The findings shed light on the issues that impact the relationship between poor company performance and CEO dismissal. In particular, the results increase understanding of t…

Slancio missionario e «vocazione» coloniale nella Guyana francese della prima metà del XIX secolo : il «Nuovo Paraguay» di Anne-Marie Javouhey

2019

Nel 1828, a Mana in Guyana, Anne-Marie Javouhey fu l’artefice di un esperimento societario complesso, tra suggestioni del socialismo utopistico e riduzioni gesuite del XVII secolo, che sarebbe diventato un laboratorio per il riscatto degli europei emarginati e per l’emancipazione dei neri d’Africa portati nelle colonie. In 1828, in Mana, in French Guyana, Anne-Marie Javouhey was the maker of a complex society experiment, between suggestions of utopian socialism and Jesuit reductions of the seventeenth century, which would become a laboratory for the redemption of marginalized Europeans and for the emancipation of the blacks of Africa brought to the colonies.

Three Stages of Consumers’ Multi-Stage Dichotomic Switching Process Pre-Switch, switch, and post-switch

2021

This research examines why and how consumers switch their mobile phones. We propose a framework that is grounded on decision-making and motivational theories and draws on the findings from a multinational qualitative survey on consumers’ mobile phone switching process. We show that consumers’ pre-switching decisions are affected by push and pull factors, their mobile phone selections are based on utilitarian or hedonic values, and their justifications for switching are based on cognition or affect. Furthermore, we identify two archetypical routes (i.e., cognitive and affective routes) and three conjoint routes that explain the dichotomic switching processes in pre-switch, switch, and post-s…

Shifts in participation frameworks in multiparty conversation

2008

Measurement of the cosmic-ray energy spectrum above 2.5×1018  eV using the Pierre Auger Observatory

2020

We report a measurement of the energy spectrum of cosmic rays for energies above 2.5×10^18 eV based on 215,030 events recorded with zenith angles below 60°. A key feature of the work is that the estimates of the energies are independent of assumptions about the unknown hadronic physics or of the primary mass composition. The measurement is the most precise made hitherto with the accumulated exposure being so large that the measurements of the flux are dominated by systematic uncertainties except at energies above 5×10^19 eV. The principal conclusions are(1) The flattening of the spectrum near 5×10^18 eV, the so-called "ankle,"is confirmed.(2) The steepening of the spectrum at around 5×10^19…

Multi Parametric Advanced Research tool for meteo satellite data interfacing with space observation of Ultra High Energy Cosmic Rays.

2006

To approach the study of the cosmic rays in the energy range E > 10 20 eV, the upper end of the spectrum observed to date, with a large statistical significance (103 events/year), and hence address the solution of several astrophysical and cosmological problems related to their existence and behaviour, a new generation of experiments will probably have to be conceived and realised. They will be based on the observation and measurements of cosmic rays from space. The extremely low rate of these events (∼ 1 event/(century × km2 × sr)) imposes a very large effective area to be monitored, of the order of 105km2, as an observational requirement to meet the target statistics. The Extreme Universe…

Probing the origin of ultra-high-energy cosmic rays with neutrinos in the EeV energy range using the Pierre Auger Observatory

2019

Neutrinos with energies above 1017 eV are detectable with the Surface Detector Array of the Pierre Auger Observatory. The identification is efficiently performed for neutrinos of all flavors interacting in the atmosphere at large zenith angles, as well as for Earth-skimming τ neutrinos with nearly tangential trajectories relative to the Earth. No neutrino candidates were found in ∼ 14.7 years of data taken up to 31 August 2018. This leads to restrictive upper bounds on their flux. The 90% C.L. single-flavor limit to the diffuse flux of ultra-high-energy neutrinos with an Eν -2 spectrum in the energy range 1.0 × 1017 eV -2.5 × 1019 eV is E2 dNν/dEν < 4.4 × 10-9 GeV cm-2 s-1 sr-1, placing str…

Limits on point-like sources of ultra-high-energy neutrinos with the Pierre Auger Observatory

2019

With the Surface Detector array (SD) of the Pierre Auger Observatory we can detect neutrinos with energy between 1017 eV and 1020 eV from point-like sources across the sky, from close to the Southern Celestial Pole up to 60 in declination, with peak sensitivities at declinations around ∼-53 and ∼+55, and an unmatched sensitivity for arrival directions in the Northern hemisphere. A search has been performed for highly-inclined air showers induced by neutrinos of all flavours with no candidate events found in data taken between 1 Jan 2004 and 31 Aug 2018. Upper limits on the neutrino flux from point-like steady sources have been derived as a function of source declination. An unrivaled sensit…

Preparation of potentially porous, chiral organometallic materials through spontaneous resolution of pincer palladium conformers.

2013

Understanding the mechanism by which advanced materials assemble is essential for the design of new materials with desired properties. Here, we report a method to form chiral, potentially porous materials through spontaneous resolution of conformers of a PCP pincer palladium complex ({2,6-bis[(di-t-butylphosphino)methyl]phenyl}palladium(II)halide). The crystallisation is controlled by weak hydrogen bonding giving rise to chiral qtz-nets and channel structures, as shown by 16 such crystal structures for X = Cl and Br with various solvents like pentane and bromobutane. The fourth ligand (in addition to the pincer ligand) on palladium plays a crucial role; the chloride and the bromide primaril…