Soft Collinear Effective Theory for heavy dark matter annihilation: spin-0, 1/2 and 1
Motoko Fujiwara (U. of Toyama)

Electroweakly interacting stable particles in the (1 − 10) TeV mass range can be a dark matter candidate with rich testability. In particular, gamma-ray line-like features are expected to be a smoking-gun signature for indirect detection. In this framework, one fundamental question follows: How can we distinguish DM spin among DM candidates with the same electroweak interaction by contrasting their predictions? A straightforward but crucial effort is to derive annihilation spectra with higher accuracy. However, one encounters complexities due to non-perturbative corrections following the mass hierarchy between heavy DM and electroweak mediators.
In this talk, we present how to construct Soft-Collinear Effective field Theory (SCET) to systematically resum large Sudakov logarithmic corrections for spin-0, 1/2, and 1 DM, and achieve accurate prediction. We focus especially on spin-1 DM, which is the last piece to complete all the possible predictions.
After specifying the leading operators to describe heavy DM annihilation in SCET, we discuss how to extract spin-dependence from the predicted gamma-ray spectrum.