Another lousy photo of the sun?

By Ken Perrott 29/03/2012

As a photo of the sun this doesn’t look very impressive – until you realise it was taken using neutrinos!

And also that it was taken through the earth – when the sun was on the other side of the earth!

An exposure of 503 day was used and neutrinos detected using a 50 000-ton water pool located 1 km underground. Neutrinos have an extremely weak interaction with other matter. Most of them pass through the earth without interaction and the detection relies on Cherenkov radiation emitted during a rare interaction with an electron in the water.

Thanks to: The Sun seen through the Earth in ’neutrino light’

0 Responses to “Another lousy photo of the sun?”

  • It‘s why favourite of those sub-atomic particle walking into a bar jokes of Brian Marlow’s is the neutrino one. I haven’t time to look up the “proper” wording, and I’m sure there a lots of variants, but I recall something like:

    A neutrino walks into a bar.

    The bartender says, “We don’t serve your kind.”

    The neutrino replies, “That’s OK. I was just passing through.”

  • This would imply that the direction of the neutrino path is detected as well. I wonder how that is done in a tank of water? Flashes of Cherenkov radiation don’t seem very ‘directional’…

  • After further quick research, it seems Cherenkov radiation is (somewhat) directional. Still, complicated, fascinating stuff…

  • I realised Cherenkov radiation is directional but the electron which the neutrino interacts with may also take on the direction of the neutrino. That would enable the detectors to have some idea of direction.