Light Vector Mediators

Light Vector Mediator Models can be strongly constrained in a Short Baseline Neutrino Experiment using a Low Energy Threshold Array as the Skipper-CCD technology can offer, since their cross section increase as the inverse of the squared of the recoil energy.

To evaluate the sensitivity of the detector we have considered a counting experiment, with the expected number of events in the range 15 -100 eV assumed to be larger than the background uncertainty with 90 % confidence level. 

As shown in the figure, there is a great improvement compared to the current limits (CONNIE:arXiv:1910.04951 , COHERENT:arXiv:1708.04255). 

Since the cross-section goes to the fourth power of the coupling g there is an improvement of more than two orders of magnitude in its sensitivity.  Similar constraints can be applied to other extended models with light mediators.