Abstract
We study the possibility of dark matter in the form of heavy neutrinos from a fourth lepton family with helicity suppressed couplings such that dark matter is produced thermally via annihilations in the early Universe. We present all possible constraints for this scenario coming from LHC and collider physics, underground direct detectors, neutrino telescopes, and indirect astrophysical searches. Although we embed the WIMP candidate within a model of composite dynamics, the majority of our results are model independent and applicable to all models where heavy neutrinos with suppressed couplings account for the dark matter abundance.
Highlights
There is a strong possibility that dark matter (DM) might be in the form of weakly interacting massive particles (WIMPs)
We study the annihilation of this DM candidate to all possible channels and we analyze the constraints derived from indirect detection
As we mentioned above if equilibrium is established the WIMP capture rate must be equal to the annihilation rate and a constraint on the WIMP annihilation rate in the Sun can be interpreted as a constraint on the WIMP-nucleon cross section
Summary
There is a strong possibility that dark matter (DM) might be in the form of weakly interacting massive particles (WIMPs). An extra benefit for such candidates is the fact that the suppression of couplings corresponds generally to lower WIMP-nucleon cross sections, lowering the bounds on the neutrino masses from direct search experiments This suppression of the couplings can be implemented in the context where a left-handed neutrino mixes with a right-handed one producing two Majorana states. Notice that if the usual seesaw mechanism is used in the present heavy neutrino set up, the lightest particle becomes dominantly left handed and has SM-like couplings to Higgs and SM gauge bosons. As we mentioned this scenario is ruled out by present experimental data (LEP, Xenon). From this point of view, N appears as a new (heavy) neutrino bearing the quantum numbers of the usual neutrinos
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
