POKER: POsitron resonant annihilation into darK mattER

by Andrea Celentano (INFN Genoa)

Tuesday 8 Jun 2021, 11:00 → 13:00 Europe/Stockholm

Zoom

Light dark matter is the new compelling hypothesis that identifies dark matter with new sub-GeV “Hidden Sector” states, neutral under Standard Model interactions and interfacing with our world through a new force. Accelerator-based searches at the intensity frontier are uniquely suited to explore it. However, current efforts are either limited by the low sensitivity or the high backgrounds. This calls for a major breakthrough in the field.

The goal of POKER is to establish and demonstrate a new approach to search for light dark matter, based on a missing energy measurement with a positron-beam, active thick-target setup.
The new technique, based on light dark matter production through positron annihilation on atomic electrons, is characterized by a larger signal yield compared to previously explored reactions, and by a unique signal signature resulting from the underlying reaction dynamics: a peak in the missing energy distribution.
The final objective of the project, approved as a 1.5 M€ ERC Starting Grant for 2020-2025, is to perform a pilot run with the 100 GeV positron beam available at the H4 beamline at CERN, to demonstrate the technique by exploring a so-far unknown territory in the Hidden Sector parameters space.

In this seminar, after a brief introduction the Hidden Sector physics case, I’ll first discuss the potential of accelerator-based light dark matter efforts. I’ll then present the POKER experiment, focusing on the active thick target - the key element of the project. I’ll finally show the sensitivity of POKER to different Light Dark Matter scenarios.

AndreaCelentano_sc_080621.mp4

CelentanoLund.pdf