Speaker
Description
The evidence for dark matter particles, $\chi$, is compelling based on Galactic to cosmological scale observations. Thus far, the promising weakly interacting massive particle scenario have eluded detection, motivating alternative models of dark matter. We consider scenarios involving superheavy dark matter (SHDM) that potentially can decay or annihilate to neutrinos and antineutrinos.
In the mass range $m_\chi = 10^7-10^{15}\,{\rm GeV}$, we evaluate the sensitivities of future observatories POEMMA and GRAND for indirect dark matter detection via the measurement of neutrino-induced extensive air showers (EAS). We compare their sensitivities to the dark matter thermally averaged annihilation cross section and dark matter decay width with the ones of IceCube, Auger and ANITA. We also show that the uncertainties related to the dark matter distribution in the Galactic halo have a large impact on the neutrino flux.
We show that a ground-based radio detector such as GRAND can achieve high sensitivities due to its large effective area and high duty cycle. Space-based Cherenkov detectors such as POEMMA that measure the EAS optical Cherenkov signal have the advantage of full-sky coverage and rapid slewing, enabling an optimized SHDM observation strategy focusing on the Galactic Center. We show that increasing the field of view of the Cherenkov detectors can significantly enhance the sensitivity. Moreover, POEMMA’s fluorescence observation mode that measures EAS above 20 EeV will achieve state-of-the-art sensitivity to SHDM properties at the highest mass scales.
Keywords
superheavy dark matter, indirect detection, ultra-high energy neutrinos
| Subcategory | Future projects |
|---|---|
| other Collaboration | POEMMA, GRAND |
