Powerful Gamma-Rays Explode From Crab Nebula; Scientists Baffled
An object in the Crab Nebula has recently emitted powerful gammy-rays which have been detected by teams of scientists from all around the world.
The source of the gamma-ray emissions seems to be an extreme object located at the Crab Nebula’s center known as pulsar.
Pulsar is the remains of the original star’s core that collapsed in on itself into a super-dense spinning neutron star.
The gamma-ray emissions possess energies exceeding 100 billion electron- volts, higher energy levels than current theoretical models can explain, from the fast spinning Crab Pulsar supernova discovered in 1968.
Theorists in those days would have never expected gamma-ray emissions to reach these types of energy levels.
“There’s just no theory that can account for what we’ve found,” said corresponding author Martin Schroedter of the Harvard-Smithsonian Center for Astrophysics, according to IBTimes.
VERITAS, which stands for Very Energetic Radiation Imaging Telescope Array System, detected these powerful emissions.
VERITAS is one of four 12-meter Cherenkov telescopes in Arizona.
It began collecting full scale observations in 2007, and its key functions include examining exploded stars, distant galaxies and powerful gamma-ray bursts with hopes of discovering evidence of mysterious dark matter particles.
Nepomuk Otte, a postdoctoral researcher at the University of California, Santa Cruz, led the team which discovered these emissions, despite being told that finding gamma-rays this powerful was highly unlikely by other researchers.
Prior to Otte’s discovery, a phenomenon known as curvature radiation, where high-energy charged particles move along a curved magnetic field- was the leading explanation for the Crab’s pulsed gamma-ray emissions.
“After many years of observations and results from the Crab, we thought we had an understanding of how it worked, and the models predicted an exponential decay of the emission spectrum above around 10 GeV. So it came as a real surprise when we found pulsed gamma-ray emissions at energies above 100 GeV,” said coauthor David Williams, adjunct professor of physics at US Santa Cruz and a member of the VERITAS collaboration.
This study was published in Friday’s issue of the journal Science.