Origin and evolution of cosmic accelerators - the unique discovery potential of an UHE neutrino telescope: Astronomy Decadal Survey (2010-2020) Science White Paper
Pisin Chen, K. D. Hoffman
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7 pages, 3 figures, submitted to US Astronomy Decadal Survey (2010-2020)
One of the most tantalizing questions in astronomy and astrophysics, namely the origin and the evolution of the cosmic accelerators that produce the highest energy cosmic rays (UHECR), may be best addressed through the observation of ultra high energy (UHE) cosmogenic neutrinos. Neutrinos travel from their source undeflected by magnetic fields and unimpeded by interactions with the cosmic microwave background. At high energies, neutrinos could be detected in dense, radio frequency (RF) transparent media via the Askaryan effect. The abundant cold ice covering the geographic South Pole, with its exceptional RF clarity, has been host to several pioneering efforts to develop this approach, including RICE and ANITA. Building on the expertise gained in these efforts, and the infrastructure developed in the construction of the IceCube optical Cherenkov observatory, a low-cost array of radio frequency antenna stations could be deployed near the Pole to efficiently detect a significant number of UHE neutrinos with degree scale angular resolution within the next decade. Such an array, if installed in close proximity to IceCube, could allow cross-calibration on a small but invaluable subset of neutrino events detected by both the optical and radio methods. In addition to providing critical information in the identification of the source of UHECRs, such an observatory could also provide a unique probe of long baseline high energy neutrino interactions unattainable in any man-made neutrino beam.
Photon Astronomy ruled the last four centuries while wider photon band ruled last radio-X-Gamma century of discovery. Present decade may see the rise and competition of UHECR and UHE Neutrino Astronomy. Tau Neutrino may win and be the first flavor revealed. It could soon rise at horizons in AUGER at EeV energies, if nucleons are the main UHECR currier. If on the contrary UHECR are Lightest nuclei (He, Li. B) UHE tau neutrino maybe suppressed at EeV and enhanced at tens -hundred PeV. Detectable in AMIGA and HEAT denser sub-array in AUGER. Within a few years.
UHECR may be either nucleons or nuclei; in the latter case the Lightest Nuclei, as He, Li, Be, explains at best the absence of Virgo signals and the crowding of events around Cen-A bent by galactic magnetic fields. This model fit the observed nuclear mass composition discovered in AUGER. However UHECR nucleons above GZK produce EeV neutrinos while Heavy Nuclei, as Fe UHECR do not produce much. UHECR He nuclei at few tens EeV suffer nuclear fragmentation (producing low energetic neutrino at tens PeVs) but it suffer anyway photo-pion GZK suppression (leading to EeV neutrinos) once above one-few …
UHE neutrinos with $E>10^{17}$ eV can be produced by ultra-high energy cosmic rays (UHECR) interacting with CMB photons (cosmogenic neutrinos) and by top-down sources, such as topological defects (TD), superheavy dark matter (SHDM) and mirror matter. Cosmogenic neutrinos are reliably predicted and their fluxes can be numerically evaluated using the observed flux of UHECR. The lower limit for the flux is obtained for the case of pure proton composition of the observed UHECR. The rigorous upper limit for cosmogenic neutrino flux also exists. The maximum neutrino energy is determined by maximum e…
Gamma-ray Bursts (GRBs) are relativistic cosmological beacons of transient high energy radiation whose afterglows span the electromagnetic spectrum. Theoretical expectations of correlated neutrino and/or gravitational wave (GW) emission position GRBs at an astrophysical nexus for a metamorphosis in our understanding of the Cosmos. This new dawn in the era of experimental (particle) astrophysics and cosmology is afforded by current and planned facilities enabling the novel astronomies of high energy neutrinos and gravitational waves, in concert with unprecedented electromagnetic coverage. In th…
In this paper we review all the up-to-date Ultra High Energy Cosmic Rays (UHECR) events reported by AUGER, by Telescope Array (TA) and by AGASA in common coordinate maps. We also confirm our earliest (2008-2013) model, where UHECR are mostly made by light nuclei (namely He, Be, B), which explains the Virgo absence and confirms M82 as the main source for North TA Hot Spot. Many more sources, such as NGC253 and several galactic ones, are possible candidates for most of the 376 UHECR events. Several correlated map, already considered in recent years, are then reported to show all the events, with…
While still in its infancy, the budding field of gravitational-wave astronomy has so far exceeded most expectations, and the achievements that have already been made bode well for the decade to come. While the discoveries made possible by LIGO have captured the imagination of experts and nonexperts alike, it is important when looking ahead to consider those discoveries in the context of the field as a whole. Just as radio, optical, and x-ray radiation probe different physical phenomena occurring on a range of length and energy scales, the future of gravitational-wave astrophysics depends on ou…
UHECR and UHE neutrino map correlation seem to most inconclusive. We show here that a few peculiar UHECR narrow clustering might be connected to a first UHE muon neutrino tracks. Moreover we discuss the best filtered and amplified UHE neutrino astronomy painted by up-going tau airshower. Their discover by new projects could be reached soon.
We study the propagation of ultra-high-energy cosmic rays in the magnetised cosmic web. We focus on the particular case of highly magnetised voids ($B \sim \text{nG}$), using the upper bounds from the Planck satellite. The cosmic web was obtained from purely magnetohydrodynamical cosmological simulations of structure formation considering different power spectra for the seed magnetic field in order to account for theoretical uncertainties. We investigate the impact of these uncertainties on the propagation of cosmic rays, showing that they can affect the measured spectrum and composition by up…
Ultra High Energy Cosmic Rays, UHECR, maybe protons, as most still believe and claim, or nuclei; in particular lightest nuclei as we advocated recently. The first (Auger Collaboration) nucleon proposal (2007)[2] foresaw to trace clearly the UHECR GZK Universe reaching far (up to 100 Mpc) Super-Galactic-Plane, with little angular dispersion. On the contrary Lightest Nuclei model (2008)[3], inspired by observed composition and by nearest CenA clustering (almost a quarter of the AUGER events) explains a modest and narrow (few Mpc) Universe view, as well as the puzzling Virgo absence: lightest nuc…
This White Paper to the National Academy of Sciences Astro2010 Decadal Review Committee outlines some of the outstanding questions regarding the assembly history of Massive Black Holes in the nuclei of galaxies and the revolutionary contributions anticipated in this field from low-frequency gravitational wave astronomy.
In this paper we showcase the importance of understanding and measuring interdisciplinarity and other -disciplinarity concepts for all scientists, the role social sciences have historically played in NASA research and missions, the sparsity of social science interdisciplinarity in space and planetary sciences, including astronomy and astrophysics, while there is an imperative necessity for it, and the example of interdisciplinarity between social sciences and astrobiology. Ultimately we give voice to the scientists across all fields with respect to their needs, aspirations and experiences in t…
We calculated for the nearest active galactic nucleus (AGN), Centaurus A (Cen A), the flux of high energy cosmic rays and of accompanying secondary photons and neutrinos expected from hadronic interactions in the source. We used as two basic models for the generation of ultrahigh energy cosmic rays (UHECR) shock acceleration in the radio jet and acceleration in the regular electromagnetic field close to the core of the AGN, normalizing the UHECR flux to the observations of the Auger experiment. Here we compare the previously obtained photon fluxes with the recent data reported by the Fermi LAT…
The Decadal Survey of Astronomy and Astrophysics created five panels to identify the science themes that would define the field's research frontiers in the coming decade. I will describe the conclusions of one of these, the Panel on Cosmology and Fundamental Physics, and comment on their relevance to the discussions at this meeting of the NASA Laboratory Astrophysics community.
Looking ahead to the next decade and imagining the landscape of astronomy in 2020, it is clear that astronomical surveys, large and small, plus extensive follow-up projects, will be a great engine of progress in our profession. Surveys have long had a critical role in astronomy, and in the coming decades will be even more central as we probe deeper into the Universe. In fact, one might call the next two decades the "Era of Great Surveys". This next generation of surveys will probe a huge range of astronomical objects and phenomena including planets, stars, gas, galaxies, background radiation, …
The Packed Ultra-wideband Mapping Array (PUMA) is a proposed low-resolution transit interferometric radio telescope operating over the frequency range 200 - 1100MHz. Its rich science portfolio will include measuring structure in the universe from redshift z = 0.3 to 6 using 21cm intensity mapping, detecting one million fast radio bursts, and monitoring thousands of pulsars. It will allow PUMA to advance science in three different areas of physics (the physics of dark energy, the physics of cosmic inflation and time-domain astrophysics). This document is a response to a request for information …
The 21cm line refers to a forbidden transition in neutral hydrogen associated with alignment of spins of the proton and electron. It is a very low energy transition that is emitted whenever there is neutral hydrogen in the Universe. Since baryons are mostly (~75%) hydrogen, one can in principle detect this emission throughout much of the history of the Universe. The dominant emission mechanism is different across cosmic ages. Before the photons decouple from matter, hydrogen is in an ionized state and does not emit in 21cm. After recombination and during the Dark Ages, at z ~ 30-1000, the 21cm…
