Solar flares can create beautiful auroras, but they can also disrupt shortwave radio communications, induce harmful currents in power grids, and damage satellites. An early warning of solar flares would give satellite and utility grid operators more time to prepare. Researchers at Purdue University have found a New system could predict solar flares, give advance warning. The system is based on the hypothesis, supported with data published in a dozen research papers since it was proposed in 2006, that radioactive decay rates are influenced by solar activity.
Ephraim Fischbach, a Purdue University professor of physics, and Jere Jenkins, a nuclear engineer and director of radiation laboratories in the School of Nuclear Engineering that discovered the effect in 2006, are leading the research. Jenkins began monitoring a detector in his lab in 2006 and discovered that the decay rate of a radioactive sample changed slightly, beginning 39 hours before a large solar flare.
Fischbach said, “It's the first time the same isotope has been used in two different experiments at two different labs, and it showed basically the same effect.”
The Purdue University release stated: “Findings showed a clear annual variation in the decay rate of a radioactive isotope called chlorine 36, with the highest rate in January and February and the lowest rate in July and August, over a period from July 2005 to June 2011.”
Fischbach, after describing the impact of the Carrington event in 1859 (also known as the 1859 solar superstorm), stated, “Because we now have a sophisticated infrastructure of satellites, power grids and all sort of electronic systems, a storm of this magnitude today would be catastrophic. Having a day and a half warning could be really helpful in averting the worst damage.”
He added that a “precursor signal” had now been observed repeatedly before solar flare activity and that he thought this might have “predictive value."
The Purdue setup uses manganese 54 as the radioactive source and a gamma-radiation detector. As the manganese 54 decays, it turns into chromium 54, emitting a gamma ray in the process. This gamma activity is recorded by the detector to measure the decay rate.
The basis of the effect is still being investigated. The effect appears to be influenced by neutrinos, but has not been confirmed.
“Since neutrinos have essentially no mass or charge, the idea that they could be interacting with anything is foreign to physics,” said Jenkins. “So, we are saying something that doesn't interact with anything is changing something that can't be changed. Either neutrinos are affecting decay rate or perhaps an unknown particle is.”