A neutrino is a subatomic particle that is very similar to an electron, but has no electrical charge and a very small mass, which might even be zero. Neutrinos are one of the most abundant particles in the universe.
When a star explodes in a supernova, one of the first things to be detected will be a blast of nutrinos.
The following images are live, taken from the Fermilab page here: https://nusoft.fnal.gov/nova/public/
Fermilab description:
The event display from the NOvA Far Detector. This image is live data (refreshes every 15 seconds, unless the detector’s not taking data for some reason). The top large rectangle is the view from above, the bottom the view from the side: here’s an example of how this maps onto a 3D detector. The NuMI beam from Fermilab is coming in from the right of the picture. Each pixel in these views is one long (15.6m), thin (4x6cm) PVC cell filled with mineral oil. A “lit” pixel is one where a charged particle crossed that cell, making a flash of light, color-coded by time (the lower-left “t(μsec)” graph). This “time” graph shows how many such hits happened at which time. The colorful displays are a 500μs long window of time, mostly showing long straight tracks from cosmic ray muons: about 40 in any given 500μs time window. The mostly blue, less busy displays are shorter (50-100μs) triggers looking for specific patterns, such as energetic showers, potential magnetic monopoles, or atmospheric neutrinos. NuMI beam Neutrinos hitting the detector and making something we can see are far more rare, only a few per week!
Fermilab description:
The event display from the NOvA Near Detector. This image is live data (refreshes every 15 seconds, unless the detector is not taking data or the beam is off). The top large rectangle is the view from above, the bottom the view from the side. The NuMI beam from Fermilab is coming in from the right of the picture and other particles cross the detector in different directions. Each pixel in these views is one PVC cell filled with mineral oil. A “lit” pixel is one where a charged particle crossed that cell, making a flash of light, color-coded by “q(ADC)” or “charge”: if a particle dumps more energy, it makes more light and thus more charge on our photosensors. The lower-left “t(μsec)” graph shows how many such hits happened at which time: this is usually a window of time 50 microseconds long around cosmic rays or 500 microseconds long around when the NuMI beam fired. The Near Detector is 100m underground, greatly reducing the number of downgoing cosmic rays, and it is close to the beam source, so the neutrino intensity is much higher than at the Far Detector. The Near Detector, being so close to the beam, has multiple neutrino interactions per beam spill: you can see the resulting particles spraying from right to left. When the neutrino beam is off (for example, during Fermilab’s summer shutdown), the few cosmic rays which make it 100m underground will be visible on this display.
Link to source page: https://nusoft.fnal.gov/nova/public/