Probing new physics with astrophysical neutrinos (original) (raw)

Interactions of astrophysical neutrinos with dark matter: a model building perspective

Journal of High Energy Physics

We explore the possibility that high energy astrophysical neutrinos can interact with the dark matter on their way to Earth. Keeping in mind that new physics might leave its signature at such energies, we have considered all possible topologies for effective interactions between neutrino and dark matter. Building models, that give rise to a significant flux suppression of astrophysical neutrinos at Earth, is rather difficult. We present a Z ′ -mediated model in this context. Encompassing a large variety of models, a wide range of dark matter masses from 10−21 eV up to a TeV, this study aims at highlighting the challenges one encounters in such a model building endeavour after satisfying various cosmological constraints, collider search limits and electroweak precision measurements.

Probing neutrino dark energy with extremely high energy cosmic neutrinos

Journal of Cosmology and Astroparticle Physics, 2006

Recently, a new non-Standard Model neutrino interaction mediated by a light scalar field was proposed, which renders the big-bang relic neutrinos of the cosmic neutrino background a natural dark energy candidate, the so-called Neutrino Dark Energy. As a further consequence of this interaction, the neutrino masses become functions of the neutrino energy densities and are thus promoted to dynamical, time/redshift dependent quantities. Such a possible neutrino mass variation introduces a redshift dependence into the resonance energies associated with the annihilation of extremely high-energy cosmic neutrinos on relic anti-neutrinos and vice versa into Z-bosons. In general, this annihilation process is expected to lead to sizeable absorption dips in the spectra to be observed on earth by neutrino observatories operating in the relevant energy region above 10^13 GeV. In our analysis, we contrast the characteristic absorption features produced by constant and varying neutrino masses, including all thermal background effects caused by the relic neutrino motion. We firstly consider neutrinos from astrophysical sources and secondly neutrinos originating from the decomposition of topological defects using the appropriate fragmentation functions. On the one hand, independent of the nature of neutrino masses, our results illustrate the discovery potential for the cosmic neutrino background by means of relic neutrino absorption spectroscopy. On the other hand, they allow to estimate the prospects for testing its possible interpretation as source of Neutrino Dark Energy within the next decade by the neutrino observatories ANITA and LOFAR.

High-Energy Neutrino Astrophysics

Annual Review of Nuclear and Particle Science, 2000

▪ High-energy (>100 MeV) neutrino astrophysics enters an era of opportunity and discovery as the sensitivity of detectors approaches astrophysically relevant flux levels. We review the major challenges for this emerging field, among which the nature of dark matter, the origin of cosmic rays, and the physics of extreme objects such as active galactic nuclei, gamma-ray bursts, pulsars, and supernova remnants are of prime importance. Variable sources at cosmological distances allow the probing of neutrino propagation properties over baselines up to about 20 orders of magnitude larger than those probed by terrestrial long-baseline experiments. We review the possible astrophysical sources of high-energy neutrinos, which also act as an irreducible background to searches for phenomena at the electroweak and grand-unified-theory symmetry-breaking scales related to possible supersymmetric dark matter and topological defects. Neutrino astronomy also has the potential to discover previous...

High-energy neutrino signatures of dark matter

Physical Review D, 2010

Decaying dark matter has previously been proposed as a possible explanation for the excess high energy cosmic ray electrons and positrons seen by PAMELA and the Fermi Gamma-Ray Space Telescope (FGST). To accommodate these signals however, the decays must be predominantly leptonic, to muons or taus, and therefore produce neutrinos, potentially detectable with the IceCube neutrino observatory. We find that,

Dark matter annihilation to neutrinos

Reviews of Modern Physics, 2021

We review the annihilation of dark matter into neutrinos over a range of dark matter masses from MeV/c 2 to ZeV/c 2. Thermally-produced models of dark matter are expected to self-annihilate to standard model products. As no such signal has yet been detected, we turn to neutrino detectors to constrain the "most invisible channel." We review the experimental techniques that are used to detect neutrinos, and revisit the expected contributions to the neutrino flux at current and upcoming neutrino experiments. We place updated constraints on the dark matter self-annhilation cross section to neutrinos σv using the most recently available data, and forecast the sensitivity of upcoming experiments such as Hyper-Kamiokande, DUNE, and IceCube Gen-2. Where possible, limits and projections are scaled to a single set of dark matter halo parameters for consistent comparison. We consider Galactic and extragalactic signals of s, p, and d-wave annihilation processes directly into neutrino pairs, yielding constraints that range from σv ∼ 2.5 × 10 −26 cm 3 s −1 at 30 MeV/c 2 to 10 −17 cm 3 s −1 at 10 11 GeV/c 2. Experiments that report directional and energy information of their events provide much stronger constraints, outlining the importance of making such data public.

Through Neutrino Eyes: The Search for New Physics

Advances in High Energy Physics, 2015

The year 2014 will mark the 60th anniversary since the neutrino detector of Frederick Reines and Clyde L. Cowan, Jr. was turned (neutrino detection in 1956). After many years, Super-Kamiokande showed in 1998 that neutrinos are massive. Today, neutrino physics has become a very active research field: there is a plethora of different neutrino experiments and theoretical studies. Subsequent measurements [2-6] of the two neutrino mass squared differences and the leptonic mixing parameters lead to a phase of precision experiments in neutrino physics. Recently the last remaining mixing angle, the 1-3 mixing angle, has been measured by the Daya Bay , Double Chooz [9, 10], and RENO [11] experiments after initial hints by T2K [12] and MINOS . Contrary to theoretical expectations from flavor symmetry considerations, it turned out to be large.

Astrophysics Uniquely Enabled by Observations of High-Energy Cosmic Neutrinos

2019

High-energy cosmic neutrinos carry unique information about the most energetic non-thermal sources in the Universe. This white paper describes the outstanding astrophysics questions that neutrino astronomy can address in the coming decade. A companion white paper discusses how the observation of cosmic neutrinos can address open questions in fundamental physics. Detailed measurements of the diffuse neutrino flux, measurements of neutrinos from point sources, and multi-messenger observations with neutrinos will enable the discovery and characterization of the most energetic sources in the Universe.

Neutrino constraints on the dark matter total annihilation cross section

Physical Review D, 2007

In the indirect detection of dark matter through its annihilation products, the signals depend on the square of the dark matter density, making precise knowledge of the distribution of dark matter in the Universe critical for robust predictions. Many studies have focused on regions where the dark matter density is greatest, e.g., the Galactic Center, as well as on the cosmic signal arising from all halos in the Universe. We focus on the signal arising from the whole Milky Way halo; this is less sensitive to uncertainties in the dark matter distribution, and especially for flatter profiles, this halo signal is larger than the cosmic signal. We illustrate this by considering a dark matter model in which the principal annihilation products are neutrinos. Since neutrinos are the least detectable Standard Model particles, a limit on their flux conservatively bounds the dark matter total self-annihilation cross section from above. By using the Milky Way halo signal, we show that previous constraints using the cosmic signal can be improved on by 1-2 orders of magnitude; dedicated experimental analyses should be able to improve both by an additional 1-2 orders of magnitude.

The Homi Bhabha Lecture Neutrino Physics and Astrophysics

2005

Neutrinos are very elusive particles. Having only weak (and gravitational) interactions they are extremely difficult to detect, but their study has been always extremely rewarding, both for physics and (more recently) astrophysics. In the last several years the progress in neutrino physics has been impressive leading to the discovery, for the first time, of physics of elementary particle phenomena beyond the Standard Theory. We have now a fair knowledge of the main features of neutrino mass-spectrum and mixing, which I’ll review in § 2. In § 3 I’ll describe the next-generation of experiments, which are under construction or concrete planning. While we know that neutrino masses are extremely small, when compared to the other elementary particles, we do not know their absolute values. This is a very difficult experimental problem, which must be attacked with complementary programmes: precision cosmology, beta-decay and double-beta decay experiments, as I’ll discuss in § 4 and § 5. Pho...

Constraints on massive neutrinos as hot dark matter

Nuclear Physics B - Proceedings Supplements, 1996

This article highlights three astronomical observations that can constrain the masses of neutrinos as hot dark matter: high-redshift damped Lya systems, the cosmic microwave background anisotropy, and gravitational lenses. Theoretical predictions and current constraints are summarised. More data are expected in the near future from all three types of observations.