New Insights into Dark Matter: CERN’s NA62 and NA64 Experiments Report Progress

The NA62 (left) and NA64 (right) experiments at CERN’s North Area.

(IN BRIEF) CERN’s NA62 and NA64 experiments, located in the North Area, have made significant progress in understanding dark matter. Operating outside the LHC’s energy range, these experiments recently revealed new findings. NA62 investigated a rare kaon decay, excluding evidence of dark bosons and setting stringent limits. Meanwhile, NA64 probed invisible light dark-matter particles using electron collision data, ruling out leading dark-matter candidates through innovative techniques. These advancements contribute to deciphering the mysterious nature of dark matter and exemplify CERN’s commitment to pushing scientific boundaries.

(PRESS RELEASE) GENEVA, 21-Aug-2023 — /EuropaWire/ — In the pursuit of unraveling the enigma of dark matter, significant strides have been achieved by the NA62 and NA64 experiments, situated at CERN‘s North Area and fed by beams from the Super Proton Synchrotron (SPS). Their latest endeavors have unveiled remarkable progress, excluding various dark-matter models and anomaly claims.

Operating in tandem with investigations at the LHC, the NA64 and NA62 experiments delve into a distinct energy realm, bolstering the quest to fathom dark matter’s elusive nature. Recent findings from both endeavors shed light on previously obscured corners of this cosmic puzzle.

Dark matter’s intangible connection with our observable universe remains a tantalizing enigma. Theorized to engage with the Standard Model through intermediary agents, researchers contemplate a plethora of possibilities, encompassing dark photons, dark scalar bosons, and axions. These could be differentiated by their interactions with Standard Model particles.

The NA62 experiment, originally devised to scrutinize ultra-rare kaon decay involving a charged pion and two neutrinos, has ventured into investigating potential contributions from dark-matter particles in a distinct kaon decay. By channeling a beam primarily composed of pions and kaons, born from the impact of the 400 GeV/c SPS proton beam on a beryllium target, researchers targeted a rare kaon decay that could signify the presence of dark bosons. While no conclusive evidence emerged for this exceptional decay or the existence of dark bosons, the team achieved a milestone by establishing the most rigorous upper limits to date. This outcome, drawn from comprehensive data analysis covering 2017 and 2018, also definitively ruled out the axion as an explanation for the ATOMKI anomaly at 17 MeV/c², aligning with prior NA64 findings.

The NA64 collaboration, on the other hand, embarked on the pursuit of invisible light dark-matter particles, theorized to interact via a possible dark photon. By scrutinizing electron collision data spanning 2016 to 2022, equivalent to 9.4 × 10¹¹ electrons on target, NA64 ventured into the uncharted territory of parameter space predicted by benchmark dark-matter models. Their pioneering efforts resulted in the exclusion of key sub-GeV dark-matter candidates for a range of particle masses, effectively dismissing both models. Employing a 100 GeV/c electron beam derived from proton interactions with a stationary target, the collaboration harnessed advanced techniques, including an active beam dump and inventive strategies to reconstruct the elusive dark photon through observable electron–positron pairs and concealed energy losses indicative of invisible decays.

These remarkable endeavors exemplify CERN’s commitment to pushing the boundaries of scientific exploration, as the world’s scientific community unites to demystify one of the cosmos’ most captivating enigmas.

Media contacts:

TeL: +41 (0) 22 767 34 32/+41 (0) 22 767 21 41
Email: press.office@cern.ch

SOURCE: CERN