Dark matter, which accounts for about a quarter of the Universe and has very little interaction with normal matter, remains a topic shrouded in mystery in the field of space science. Despite numerous astrophysical and cosmological observations that confirm its existence, such as through images captured by the James Webb telescope, there is still a lack of direct experimental evidence for dark matter.
Professor Dipak Kar from the School of Physics at the University of Vitvatersrand in Johannesburg, South Africa, has voiced his approval, stating, “The pursuit of answers to the deepest secrets of the universe is the purpose of our scientific work.” Kar and his former graduate student Sunhu, who is now a post-doctoral researcher at the University of Manchester, are part of the team of scientists working on the ATLAS experiment at CERN (European Nuclear Research Organization). They have proposed a new method for searching for dark matter, which has been published in the journal Physics Letters B.
Previous efforts to detect dark matter have largely focused on weakly interacting massive particles (WIMPs), which do not emit or absorb light. However, no evidence for the existence of WIMPs has been found, prompting scientists to explore alternative approaches.
Kar explains, “We started considering whether dark matter particles could be produced within standard particles known as jets.” This led to the investigation of a new type of signature in detectors called semi-visible jets, which had previously been overlooked by scientists.
Semi-visible jets can occur when hypothetical dark quarks partially decay into standard quarks (known particles) and stable dark hadrons (the “invisible” component). As these jets are produced in pairs, often accompanied by additional jets from the standard model, any energy imbalance or missing energy in the detector provides an indication that the jets are not completely balanced.
Sunhu emphasizes the significance of their work, stating, “Despite the lack of direct detection of dark matter, my doctoral dissertation establishes strict upper limits for its potential production, thereby stimulating further research in this field.” The team’s innovative approach opens up promising avenues for the study of dark matter, a mysterious substance that shapes the structure of the universe.