Journal of High Energy Physics (Oct 2020)
The dark side of 4321
Abstract
Abstract The evidence of Dark Matter (DM) is one of the strongest observational arguments in favor of physics beyond the Standard Model. Despite expectations, a similar evidence has been lacking so far in collider searches, with the possible exception of B-physics discrepancies, a coherent set of persistent deviations in a homogeneous dataset consisting of b → c and b → s semi-leptonic transitions. We explore the question whether DM and the B discrepancies may have a common origin. We do so in the context of the so-called 4321 gauge model, a UV-complete and calculable setup that yields a U 1 leptoquark, the by far most successful single mediator able to explain the B anomalies, along with other new gauge bosons, including a Z′. Adding to this setup a ‘minimal’ DM fermionic multiplet, consisting of a 4 under the 4321’s SU(4), we find the resulting model in natural agreement with the relic-density observation and with the most severe direct-detection bounds, in the sense that the parameter space selected by B physics is also the one favored by DM phenomenology. The DM candidate is a particle with a mass in the WIMP range, freeze-out dynamics includes a co-annihilator (the ‘rest’ of the 4 multiplet), and the most important gauge mediator in the DM sector is the Z′.
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