A recent article in Scientific American discussed the Telescope Array Project's detection of the second-highest energy particle ever recorded. In the article, the author speaks with physicists from universities around the world, both those who were involved in the discovery of this new ultra high-energy cosmic ray (UHECR), as well as several who were not.
One explanation proposed in the article is that the particle could have been an iron-nucleus UHECR. Iron nuclei are some of the most massive particles found among cosmic rays; however, Dr. David Kieda of the University of Utah, one of the scientists who co-discovered the only other particle with more energy back in 1991, found this hypothesis unconvincing.
“[An iron-nucleus UHECR is] bound together by a relatively weak amount of energy, compared to the process that’s accelerating it. It’s like trying to take a blob of Jell-O and speed it way up without destroying it.”
The article goes on to discuss the potential for new research into cosmic rays in the future, including the possibility of new space telescopes, as well as the expansion of ground-based detectors such as the Telescope Array in Utah and the Auger Observatory in Argentina.
The full article can be found here.
