Our Milky Way is glowing at the centre and this could be due to the presence of dark matter, as per a recent study. The mystery has puzzled astronomers across the globe ever since the glow- scientifically known as the Galactic Center GeV Excess (GCE)-was discovered in 2009.
The glow, which appears in the form of gamma radiation, is created by ‘dark matter’. As per scientists, this makes up 80% of the matter in the universe.
The new theory by Mattia Di Mauro has been formulated on the basis of data collected by the Fermi Large Area Telescope (LAT) over a period of 11 years. In addition to it, the data from the Pamela detector and the Alpha Magnetic Spectrometer experiment (AMS-02) aboard the International Space Station was also analysed.
“If the excess was, for example, caused by the interaction between cosmic rays and atoms, we would expect to observe its greater spatial distribution at lower energies and its lower diffusion at higher energies due to the propagations of cosmic particles. My study, on the other hand, underlines how the spatial distribution of the excess does not change as a function of energy,” said Mattia Di Mauro, National Institute for Nuclear Physics.
According to the study, in the area surrounding the Galactic Center, a dark matter particle is annihilating with a cross-section within a factor of a few of the value predicted for a thermal relic.
Di Mauro’s study has used the broadest set of data from Fermi collected last year. It has also minimized the uncertainties introduced by background radiation. This, in turn, has provided information about the spatial distribution of the GCE that can help rule out various explanations.
What is Dark Matter?
Scientists have defined Dark Matter as the material they cannot directly observe. It accounts for around 80% of the mass of the universe. Dark matter does not emit light or energy. It is called dark matter because it does not absorb, reflect or emit electromagnetic radiation, making it difficult to detect.