First results from LHAASO place tighter constraints on dark matter’s lifetime

Scientists from the Giant Excessive Altitude Air Bathe Observatory (LHAASO) have offered roughly 1.5 years of observational information, calculating new limits on the lifetime of heavy dark matter particles which have lots between 10⁵ and 10⁹ giga-electron volts.

The examine, titled “Constraints on heavy decaying dark matter from 570 days of LHAASO observations,” was not too long ago revealed in Physics Overview Letters.

The gravitational mannequin of the Milky Way exhibits that there’s a very excessive density of dark matter within the galactic middle, and the gamma rays produced by the decay of this dark matter will radiate from the galactic center to the environment for a whole bunch of light-years and even hundreds of light-years. Nevertheless, for a very long time, the statement of ultra-high-energy gamma rays produced by heavy dark matter has been sophisticated by the presence of different background radiation.

Because of its unprecedentedly excessive detection sensitivity to ultra-high-energy gamma rays (>100 TeV), LHAASO has the very distinctive potential to look at gamma rays decaying from heavy dark matter. LHAASO can get rid of background occasions by practically six orders of magnitude above 100 TeV, which considerably reduces background interference and improves the power to seize gamma rays.

By utilizing information from the KM2A subarray of LHAASO, scientists measured the depth of ultra-high-energy gamma rays past the galactic plane and place among the strongest restrict to date for the lifetime of heavy dark matter. The restrict is sort of 10 occasions increased than earlier outcomes. This examine exhibits that PeV mass dark matter has a lifetime of at the very least about billion trillion years (10²¹ years).

LHAASO’s observations of gamma rays are extremely complementary to different experiments within the seek for dark matter (resembling neutrino statement experiments). Because the LHAASO full array operates stably and steadily accumulates information, this restrict might be additional elevated.