Ciutats

[p.4] "La culpa de tot és dels grans"[p.8] Què van fer les sargantanes i els dragons?[p.13] Desenvolupament urbà sostenible[p.21] Una dura lliçó per ser apresa[p.32] La ciutat com a aventura iniciàtica[p.37] Una competició per la sostenibilitat?[p.44] Entrevista a Salvador RuedaPeer Reviewe

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

Ciutats

[p.4] "La culpa de tot és dels grans"[p.8] Què van fer les sargantanes i els dragons?[p.13] Desenvolupament urbà sostenible[p.21] Una dura lliçó per ser apresa[p.32] La ciutat com a aventura iniciàtica[p.37] Una competició per la sostenibilitat?[p.44] Entrevista a Salvador RuedaPeer Reviewe