Cosmic x-rays may provide clues to the nature of dark matter

According to common theory, dark matter must exist because otherwise stars would not continue to rotate around the center of their galaxies as they in fact do. Among the particularly favored candidates for dark matter are so-called weakly interacting massive particles,
or WIMPs. Researchers are searching for these in the Italian Gran Sasso underground laboratory, for example.
But recent scientific publications in the field of astroparticle physics are increasingly taking the view that WIMPs are unlikely to be viable prospects when it comes to dark matter.
"We, too, are currently actively on the search for possible alternatives," said Professor Joachim Kopp of Mainz University.

The physicist, together with his colleagues Vedran Brdar, Jia Liu, and Xiao-Ping Want, took a closer look at the results of observations undertaken by several independent groups in 2014.
The groups reported the presence of a previously undetected spectral line, with an energy of 3.5 kiloelectron volts (keV), in x-ray light from distant galaxies and galaxy clusters.
This unusual x-ray radiation might offer a clue to the nature of dark matter.
It has been previously pointed out that dark matter particles might decay, thereby emitting x-rays.
However, Joachim Kopp's team at the Mainz-based Cluster of Excellence on Precision Physics, Fundamental Interactions and Structure of Matter (PRISMA) is taking another approach.

論文
X-Ray Lines from Dark Matter Annihilation at the keV Scale.
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.120.061301

転載元
https://www.sciencedaily.com/releases/2018/02/180208104206.htm
つづく