Joint Theory Seminar
Speaker: Flip Tanedo (LEPP Cornell University)
Title: Goldstone Fermion Dark Matter
Host: Yuhsin Tsai
Room: 432
Abstract: Nonlinear realizations describe the low-energy degrees of freedom of strongly coupled theories with spontaneously broken symmetry. When combined with SUSY, the Goldstone bosons of these theories are complex fields with "Goldstone fermion" super-partners. These, in turn, offer novel weakly interacting massive particle (WIMP) dark matter candidates.
Typical WIMP candidates in the MSSM require a tuned spectrum to simultaneously obtain the observed dark matter relic abundance and avoid the upper limit on the WIMP nucleon cross section from direct detection experiments. Goldstone fermions can avoid this tuning since their annihilation rate is naturally fixed by interactions within the nonlinearly realized sector while the direct detection cross section is controlled by mixing with the Higgs sector. For a global U(1) broken at the TeV scale, one naturally obtains a 100 GeV scale Higgs-portal WIMP candidate whose direct detection rate is suppressed by three orders of magnitude.
