Optimal Heliomobile Field Configurations In A Variable-Geometry Test Facility For Central Receiver Solar Systems

L'apparato sperimentale per sistemi a torre a geometria variabile costruito presso il CTAER di Tabernas (Almería, Spagna) è una novità nel mondo del solare termodinamico. Attraverso un codice scritto in Matlab si è valutato ed ottimizzato il rendimento ottico di un ridotto campo solare mobile; un'analisi comparativa con un sistema concentratore fisso e la validazione dei risultati ottenuti mediante il software di ray-tracing Tonatiuh evidenziano le caratteristiche della struttura studiataope

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements