Neutrinos Flashcards
What discovery made the scientists realize that there’s physics beyond the Standard Model ?
The discovery of the oscillation of the neutrinos => the fact that they can change of flavour
Neutrinos propagate in … but they are produced and detected in … ?
Neutrinos propagate in MASS EIGENSTATES but they are produced and detected in FLAVOR EINGENSTATES.
Neutrinos … in mass eigenstates but they are … and … in flavour eigenstates
Neutrinos PROPAGATE is mass eigenstates but they are PRODUCED and DETECTED in flavour eigenstates.
How do we compute the neutrinos vacuum oscillations?
We use the mixing matrix between two flavours
How do we call the distance for one complete flavour oscillation?
The mixing length L
How do neutrinos of different flavours behave in matter?
Neutrinos of different flavours interact differently with the medium. Indeed, electronic neutrinos couple strongly with normal matter because it is made of electrons, and not of taus or muons.
This will affect the effective mass of neutrinos and therefore their propagation and oscillation.
Name the three neutrinos detectors
IceCube, ANTARES, Baikal
What is the observed upper limit for neutrinos energy ?
about 10^7 GeV, as seen by IceCube
Galactic possible source of neutrinos?
- Cosmic ray interacting with the gas in the Milky Way disk
- Supernovae accelerating particles in molecular clouds
- Astrophysical neutrinos from pion decay
Extragalactic possible sources of neutrinos?
- Cosmic ray interacting with CMB and EBL and producing pions that decay into neutrinos
- Active galaxies have a SMBH producing a proton jet interacting with the radiation field to photo-pion production
-GRBV can also produce neutrinos by photo-pion mechanism
How are solar neutrinos produced?
By proton-proton reaction : p + p -> D + e- + v
What is the advantage of solar neutrinos in comparison with photons?
They espace from the Sun in 2s => they are real ttime messengers
What are supernovae neutrinos?
That is how we call neutrinos from gravitational collapse.
How are supernovae neutrinos produced?
A huge fraction of the collapse energy must be release in a short time. ONly neutrinos can do it because they wekly interact with matter. These neutrinos have energies about 10-20MeV.
