Related papers: Cosmic Neutrino Last Scattering Surface
Neutrinos are the second most abundant particles in the universe according to the Standard Model, yet they are the least likely to interact. This feature implies that detecting a neutrino can reveal valuable insights into its source. Among…
The atmospheric neutrino beam simultaneously spans a range of pathlengths from ten to ten thousand kilometers, which correspond respectively to downward- and upward-going neutrinos. As with any neutrino oscillation experiment, also in this…
The spectrum of the Cosmic Microwave Background follows Planck's black body radiation formula and shows a remarkable constant temperature of T = 2.7. About 380 000 years after the Big Bang at a temperature of T = 3000 Kelvin in the matter…
Since neutrinos have mass differences, they could decay into one another. But their lifetimes are likely long, even when shortened by new physics, so decay likely impacts neutrinos only during long trips. This makes high-energy…
In the past four decades a new type of astronomy has emerged, where instead of looking up into the sky "telescopes" are buried miles underground or deep under water or ice and search not for photons (that is, light), but rather for…
We explore the cosmological signals of theories in which the neutrinos decay into invisible dark radiation after becoming non-relativistic. We show that in this scenario, near-future large scale structure measurements from the Euclid…
The Cosmic Neutrino Background (C$\nu$B) constitutes the last observable prediction of the standard cosmological model, which has yet to be detected directly. In this work, we show how the coherent scattering of neutrinos off dense neutron…
Core collapse supernova simulations can be sensitive to neutrino interactions near the neutrinosphere. This is the surface of last scattering. We model the neutrinosphere region as a warm unitary gas of neutrons. A unitary gas is a low…
Precision measurements of the acoustic peaks of the cosmic microwave background indicate that neutrinos must be freely streaming at the photon decoupling epoch when T ~ 0.3 eV. This requirement implies restrictive limits on ``secret…
Neutrino scattering at low energies is essential for a variety of timely applications potentially having fundamental implications, e.g. unraveling unknown neutrino properties, such as the third neutrino mixing angle, the detection of the…
We estimate energy spectra and fluxes at the Earth's surface of the cosmic and Galactic neutrino backgrounds produced by thermonuclear reactions in stars. The extra-galactic component is obtained by combining the most recent estimates of…
In the primordial Universe, neutrino decoupling occurs only slightly before electron-positron annihilations. This leads notably to an increased neutrino energy density compared to the standard instantaneous decoupling approximation,…
Neutrinos can play an important role in the evolution of the Universe, modifying some of the cosmological observables. In this contribution we summarize the main aspects of cosmological relic neutrinos and we describe how the precision of…
The modern picture of the neutrino as a multiple mass highly mixed neutral particle has emerged over 40 years of study. Best known of the issues leading to this picture was the apparent loss of neutrinos coming from the sun. This article…
The announcement by the IceCube Collaboration of the observation of 28 cosmic neutrino candidates has been greeted with a great deal of justified excitement. The data reported so far depart by 4.3\sigma from the expected atmospheric…
With the educated, interested non-specialist as the target audience, we overview what is known and not known about contemporary neutrino physics. Theory tells us that neutrinos are the second-most common particle in the Universe, behind…
The physics of the mysterious and stealthy neutrino is at the heart of many phenomena in the cosmos. These particles interact with matter and with each other through the aptly named weak interaction. At typical astrophysical energies the…
We re-investigate the evolution of the strongly degenerate neutrinos in the early universe. With the larger degeneracy, the neutrino number freezes at higher temperatures because the neutrino annihilation rate decreases. We consider very…
We point out that in scenarios with a low reheating temperature $T_R << 100$ MeV at the end of (the last episode of) inflation or entropy production, the abundance of sterile neutrinos becomes largely independent of their coupling to active…
Recent data lead us to a simple and intriguing form of the neutrino mass matrix. In particular, we find solar neutrino oscillations to be nearly maximal (and rule out the small-angle MSW explanation of solar neutrino observations) if relic…