"'Posible, pero no interesante' – respondió Lönnrot –. ‘Usted replicará que la realidad no tiene la menor obligación de ser interesante. Yo le replicaré que la realidad puede prescindir de esa obligación, pero no las hipótesis.’"

(La Muerte y la Brújula, Jorge Luis Borges)

["'It’s possible, but not interesting,' Lönnrot answered. 'You will reply that reality hasn’t the slightest need to be of interest. And I’ll answer you that reality may avoid the obligation to be interesting, but that hypotheses may not.'"]

(La Muerte y la Brújula, Jorge Luis Borges)

The IceCube Neutrino Observatory is a neutrino detector located in the antarctic continent at the geographical South Pole. It is the realization of a long dream that started in the mid-eighties of detecting high-energy astrophysical neutrinos. These high-energy neutrinos carry about a million times the energy of a proton and are produced in yet unidentified sources.

In order to achieve this feat the IceCube collaboration, comprised of about three hundred scientists in forty eight institutions and spread around twelve countries, has instrumented one cubic kilometer of ultra-clear ice with light detectors called DOMs. Each DOM, initials for Digital Optical Module, is a basketball-size independent detector enclosed in a pressure resisting vessel containing one photomultiplier tube. These extremely sensitive light detectors capture the light produced by the interaction of ultra-high energy particles in the deep ice.

The figure on the left shows the amount of events triggered in a couple of microseconds in IceCube. Many of these events are induces by cosmic ray produced muons (electrons more massive brothers) in the south pole atmosphere. Every million interaction of cosmic ray induced muon one neutrino will make a recognizable signal in our detector.

All of IceCube's neutrinos are very special, but we can group them by origin. The most special, but rare ones are from high-energy astrophysical sources. Those types of neutrinos are detected at a rate of about ~30 per year. These very high energy neutrinos can be a gateway to new physics, as we discussed in here.

The other ones are produced in cosmic ray shows in the Earth atmosphere and thus are named atmospheric neutrinos. IceCube detects and precisely reconstructs ~ 20 000 of these neutrinos per year. My work involves in using these neutrinos to constrain new neutrino phenomena.