A nearby supernova could end the search for dark matter, new research claims
The pursuit of understanding dark matter, which makes up 85 percent of the universe’s mass, could take a significant step forward with a nearby supernova. Researchers at the University of California, Berkeley, led by Associate Professor of Physics Benjamin Safdi, have theorized that the elusive particle known as the axion could be detected within moments of gamma ray emission from such an event. Axions, which are expected to form during the collapse of a massive star’s core into a neutron star, could transform into gamma rays in the presence of intense magnetic fields, marking a potential breakthrough in physics.
Potential role of gamma-ray telescopes
The study was published in Physical Review Letters and revealed that the gamma rays produced by axions could confirm the particle’s mass and properties if it were detected. The Fermi Gamma-ray Space Telescope, currently the only gamma-ray observatory in orbit, should be aimed directly at the supernova, with the probability of this alignment estimated at only 10 percent. A detection would revolutionize dark matter researchwhile the absence of gamma rays would limit the range of axion masses, rendering many existing dark matter experiments redundant.
Challenges in catching the event
For detection, the supernova must occur within the Milky Way or its satellite galaxies – an event that occurs on average once every few decades. The last such event, supernova 1987A, lacked gamma-ray equipment that was sensitive enough. Stressing the need for preparedness, Safdi proposed a constellation of satellites called GALAXIS to ensure 24/7 sky coverage.
The theoretical importance of Axion
The axion, supported by theories such as quantum chromodynamics (QCD) and string theory, bridges gaps in physics and potentially connects gravity with quantum mechanics. Unlike neutrinos, axions can be converted into photons in strong magnetic fields, producing unique signals. Laboratory experiments such as ABRACADABRA and ALPHA also probe for axions, but their sensitivity is limited compared to the scenario of a nearby supernova. Safdi expressed the urgency, noting that missing such an event could delay the detection of axions by decades, underscoring the high stakes of this astrophysical undertaking.
