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WIMPs, weakly-interacting massive particles, have been leading candidates for particle dark matter for decades, and they remain a viable and highly motivated possibility. In these lectures, I describe the basic motivations for WIMPs, beginning with the WIMP miracle and its under-appreciated cousin, the discrete WIMP miracle. I then give an overview of some of the basic features of WIMPs and how to find them. These lectures conclude with some variations on the WIMP theme that have by now become significant topics in their own right and illustrate the richness of the WIMP paradigm.
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Is a Miracle-less WIMP Ruled out?
We examine a real electroweak triplet scalar field as dark matter,abandoning the requirement that its relic abundance is determinedthrough freeze out in a standard cosmological history (a situation whichwe refer to as `miracle-less WIMP’). We extract the bounds on such aparticle from collider searches, searches for direct scattering withterrestrial targets, and searches for the indirect products ofannihilation. Each type of search provides complementary information,and each is most effective in a different region of parameter space. LHCsearches tend to be highly dependent on the mass of the SU(2) chargedpartner state, and are effective for very large or very tiny masssplitting between it and the neutral dark matter component. Directsearches are very effective at bounding the Higgs portal coupling, butineffective once it falls below \lambda_{\text{eff}} \lesssim 10^{-3} λ eff ≲ 10 − 3 .Indirect searches suffer from large astrophysical uncertainties due tothe backgrounds and J J -factors,but do provide key information for \sim ∼ 100 GeV to TeV masses. Synthesizing the allowed parameter space, thisexample of WIMP dark matter remains viable, but only in miracle-lessregimes.
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- Award ID(s):
- 1915005
- PAR ID:
- 10346109
- Date Published:
- Journal Name:
- SciPost Physics
- Volume:
- 11
- Issue:
- 2
- ISSN:
- 2542-4653
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.21468/SciPostPhys.11.2.019
