Erratum: Gamma-ray boxes from axion-mediated dark matter

Abstract

Here we report a mistake in the dark matter annihilation amplitudes presented in the published version of this work. In particular, we provide the corrected version of eqs. (3.4)-(3.6) and derive the corresponding repercussions on our results. None of our conclusions changes due to this correction.

On the sensitivity of CTA to gamma-ray boxes from multi-TeV dark matter

“…The search for gamma-ray boxes originated in dark matter annihilations or decays has been proposed and discussed at length elsewhere [33,39]. Here, we simply recall the essential phenomenology to compute the gamma-ray flux at Earth and outline concrete dark matter models for illustration purposes.…”

“…Consider for concreteness the case of Dirac dark matter particles χ annihilating into two scalars φ which decay into a pair of photons each: χ χ → φφ → 4γ (for variations on this scenario we refer the reader to Refs. [33,39]). The scalars are sufficiently short-lived such that their decays occur basically in the same position as the dark matter annihilations -in practice, since we are interested in regions of the Galaxy spanning hundreds of parsec, decay times below about 10 2 − 10 3 yr are sufficiently short for our purposes.…”

“…Moreover, in contrast to annihilations generating gammaray lines [34][35][36] or internal bremsstrahlung [37,38], which have cross sections suppressed with respect to the thermal value by a factor O(α 2 ) and O(α), respectively, with α the electromagnetic coupling constant, the gamma-ray box has an a priori unsuppressed cross section and can therefore generate an intense, and at the same time very characteristic, signal in the gamma-ray spectrum. In fact, in the most favourable scenarios, current instruments are sensitive to gamma-ray boxes generated by annihilations of WIMPs with masses as large as ∼ 10 TeV [39]. Motivated by the excellent sensitivity of current instruments to gammaray boxes, we investigate in this paper the prospects to observe this sharp feature with the future Cherenkov Telescope Array (CTA) [40,41].…”

The waning of the WIMP? A review of models, searches, and constraints

“…As pointed out in Refs. [299,302,303] the annihilation into Sa can lead to box shaped gamma-ray signals which could be probed in the near future by CTA. However, our choice for m a , implies a too suppressed decay branching ratio for a → γ γ process.…”

Cornering top-philic dark matter with colliders and cosmology: the importance of QCD corrections

“…for larger dark matter masses (following the procedure of Ref. [21]). As shown in Figure 3, present and future gamma-ray and cosmic-ray data turns out to be sensitive to only a small fraction of the model parameter space.…”