The propagation of UHECR nuclei for A=1 (protons) to A=56 (iron) from cosmological sources through extragalactic space is discussed in the first lecture. This is followed in the second and third lectures by a consideration of the generation and propagation of secondary particles produced via the UHECR loss interactions. In the second lecture we focus on the generation of the diffuse cosmogenic UHE-neutrino flux. In the third lecture we investigate the arriving flux of UHE-photon flux at Earth. In the final lecture the results of the previous lectures are put together in order to provide new insights into UHECR sources. The first of these providing a means with which to investigate the local population of UHECR sources through the measurement of the UHECR spectrum and their photon fraction at Earth. The second of these providing contraints on the UHECR source radiation fields through the possible observation at Earth of UHECR nuclei.
The new field of multi-messenger astronomy aims at the study of astronomical sources using different types of "messenger" particles: photons, neutrinos, cosmic rays and gravitational waves. These lectures provide an introductory overview of the observational techniques used for each type of astronomical messenger, of different types of astronomical sources observed through different messenger channels and of the main physical processes involved in production of the messenger particles and their propagation through the Universe.
Up to date, there is no consensus regarding the origin of ultra-high energy cosmic rays (UHECR) beyond the Greisen--Zatsepin--Kuzmin (GZK) limit. In order for these UHECRs to reach the Earth, an extremely suppressed interaction between them and the cosmic microwave background (CMB) is required, which is impossible for standard model (SM) particles, except neutrinos. In this letter, we present constraints on the parameter space of models involving axion-like particles and dark photons, as candidates for UHECRs, by assuming that these particles can traverse the visible Universe without decaying.…
While the Pierre Auger Observatory is a very successful instrument for ultra-high energy cosmic ray (UHECR) detection, it is increasingly used as part of various types of multi-messenger searches, in which it contributes with searches for air showers induced by atomic nuclei, neutrons, photons, and neutrinos. We present an overview of the multi-messenger activities of the Pierre Auger Observatory. The overview includes: searches for ultra-high energy photons and neutrinos detected by the Pierre Auger Observatory in coincidence with gravitational wave events detected by LIGO and Virgo; searches…
The present work discusses the development of the radio technique for detection of ultra-high energy air-showers induced by cosmic radiation, and the prospects of its application in the future multi-messenger activities, particularly for detection of ultra-high energy cosmic rays, gamma rays and neutrinos. It gives an overview of the results achieved by the modern digital radio arrays, as well as discuss present challenges and future prospects.}
Recent work highlights that tens of Galactic double neutron stars are likely to be detectable in the millihertz band of the space-based gravitational-wave observatory, LISA. Kyutoku and Nishino point out that some of these binaries might be detectable as radio pulsars using the Square Kilometer Array (SKA). We point out that the joint LISA+SKA detection of a $f_\text{gw}\gtrsim$1 mHz binary, corresponding to a binary period of $\lesssim$400 s, would enable precision measurements of ultra-relativistic phenomena. We show that, given plausible assumptions, multi-messenger observations of ultra-re…
Over the past decade the multi-messenger astrophysics has emerged as a distinct discipline, providing unique insights into the properties of high-energy phenomena in the Universe. The Pierre Auger Observatory, located in Malargüe, Argentina, is the world's largest cosmic ray detector sensitive to photons, neutrinos, and hadrons at ultra-high energies. Using its data, stringent limits on photon and neutrino fluxes at EeV energies have been obtained. The collaboration uses the excellent angular resolution and the neutrino identification capabilities of the Observatory for follow-up studies of ev…
Antares is currently the largest neutrino telescope operating in the Northern Hemisphere, aiming at the detection of high-energy neutrinos from astrophysical sources. Such observations would provide important clues about the processes at work in those sources, and possibly help solve the puzzle of ultra-high energy cosmic rays. In this context, Antares is developing several programs to improve its capabilities of revealing possible spatial and/or temporal correlations of neutrinos with other cosmic messengers: photons, cosmic rays and gravitational waves. The neutrino telescope and its most re…
In order to interpret cosmic ray observations, detailed modeling of propagation effects invoking all important messengers is necessary. We introduce a new photon production and propagation code as an inherent part of the CRPropa 3 software framework. By implementing additional photon production channels, which are important for energies below 10**18 eV, this code can be used for multi-messenger studies connecting the TeV and sub EeV energy regime and for interpreting models of ultra-high energy cosmic ray sources. We discuss the importance of the individual production channels and propagation …
Ultra-high energy neutrinos hold promise as cosmic messengers to advance the understanding of extreme astrophysical objects and environments as well as possible probes for discovering new physics. This proceeding describes the motivation for measuring high energy neutrinos. A short summary of the mechanisms for producing high energy neutrinos is provided along with an overview of current and proposed modes of detection. The science reach of the field is also briefly surveyed. As an example of the potential of neutrinos as cosmic messengers, the recent results from an IceCube Collaboration real…
The rise in the energy spectrum of the positron ratio, observed by the PAMELA satellite above 10 GeV, and other cosmic ray measurements, have been interpreted as a possible signature of Dark Matter annihilation in the Galaxy. However, the large number of free parameters, and the large astrophysical uncertainties, make it difficult to do conclusive statements about the viability of this scenario. Here, we perform a multi-wavelength, multi-messenger analysis, that combines in a consistent way the constraints arising from different astrophysical observations. We show that if standard assumptions …
We discuss the production of multiple astrophysical messengers (neutrinos, cosmic rays, gamma-rays) in the Gamma-Ray Burst (GRB) internal shock scenario, focusing on the impact of the collision dynamics between two shells on the fireball evolution. In addition to the inelastic case, in which plasma shells merge when they collide, we study the Ultra Efficient Shock scenario, in which a fraction of the internal energy is re-converted into kinetic energy and, consequently, the two shells survive and remain in the system. We find that in all cases a quasi-diffuse neutrino flux from GRBs at the lev…
Knowledge of the distant high-energy universe comes from photons, ultra-high energy cosmic rays (UHECRs), high-energy neutrinos, and gravitational waves. The theory of high-energy messengers reviewed here focuses on the extragalactic background light at all wavelengths, cosmic rays and magnetic fields in intergalactic space, and neutrinos of extragalactic origin. Comparisons are drawn between the intensities of photons and UHECRs in intergalactic space, and the high-energy neutrinos recently detected with IceCube at about the Waxman-Bahcall flux. Source candidates for UHECRs and high-energy ne…
The origin of ultra-high energy cosmic rays (UHECRs) is one of the most mystifying issues in astroparticle physics. It has been suggested that gamma-ray bursts (GRBs) are excellent acceleration sites for cosmic rays. The propagation of UHECRs from the GRB host galaxy to the Earth should generate delayed secondary photons and neutrinos. Here we present a dedicated search for delayed UHECR and neutrino emission centered around the position of nearby GRB 980425/SN 1998bw. Located at a distance of 36.9 Mpc, GRB 980425/SN 1998bw is well within the Greisen-Zatsepin-Kuzmin (GZK) distance horizon. We …
The cubic kilometer IceCube neutrino telescope now operating at the South Pole in a near complete configuration observes the neutrino sky with an unprecedented sensitivity to galactic and extra-galactic cosmic ray accelerators. Within the multi-messenger framework, IceCube offers unique capabilities to correlate and contrast the neutrino sky with the gamma-ray sky and ultra high energy cosmic rays and complements other indirect and direct dark matter search programs. We review here the status of the experiment and recent selected results. A discussion of the implications of the observations wi…
Cosmic rays are a sample of solar, galactic and extragalactic matter. Their origin and properties are one of the most intriguing question in modern astrophysics. The most energetic events and active objects in the Universe: supernovae explosion, pulsars, relativistic jets, active galactic nuclei, have been proposed as sources of cosmic rays although unambiguous evidences have still to be found. Electrons, while comprising ~1% of the cosmic radiation, have unique features providing important information regarding the origin and propagation of cosmic rays in the Galaxy that is not accessible fro…
The ANTARES Collaboration has completed in 2008 the deployment of what is currently the largest high energy neutrino detector in the Northern hemisphere. The search for cosmic neutrinos in the energy range between tens of GeV and tens of PeV is performed by means of a three dimensional array of photomultiplier tubes (PMTs), arranged on 12 vertical structures (strings) located in the Mediterranean Sea at a depth of about 2500 meters. The detection principle relies on the identification of the Cherenkov light produced as ultra-relativistic muons propagate in water. The main goal of the detector …
GW170817/GRB170817A probably marks a double neutron star coalescence. Extended Emission $t_s\simeq (0.67\pm0.03)$\,s post-merger shows an estimated energy output ${\cal E}\simeq (3.5\pm1)\%M_\odot c^2$ determined by response curves to power-law signal injections, where $c$ is the velocity of light. It provides calorimetric evidence for a rotating black hole of $\sim 3M_\odot$, inheriting the angular momentum $J$ of the merged hyper-massive neutron star in the immediate aftermath of GW170817 following core-collapse about or prior to $t_s$. Core collapse greatly increases the central energy rese…
The IceCube, Pierre Auger and Telescope Array Collaborations have recently reported results on neutral particles (neutrons, photons and neutrinos) which complement the measurements on charged primary cosmic rays at ultra-high energy. The complementarity between these messengers and between their detections are outlined. The current status of their search is reviewed and a cross-correlation analysis between the available results is performed. The expectations for photon and neutrino detections in the near future are also presented.
High-Synchrotron-Peaked BL Lacs as Multi-Messenger Sources: Connecting Ultra-High-Energy Cosmic Rays and Neutrinos
Unidade Acadêmica de Física, Universidade Federal de Campina Grande (UAF-UFCG)（坎皮纳格兰德联邦大学物理学术单位）；Instituto de Física, Universidade de São Paulo (IFUSP)（圣保罗大学物理研究所）；Departamento de Engenharias e Exatas, Universidade Federal do Paraná (UFPR)（巴拉那联邦大学工程与理学院）；Programa de Pós-Graduação em Física, Departamento de Física, Universidade Estadual de Londrina (UEL)（隆德里纳州立大学物理系物理学研究生项目）；Programa de Pós-Graduação em Física e Astronomia, Universidade Tecnológica Federal do Paraná (UTFPR)（巴拉那联邦技术大学物理与天文学研究生项目）；Programa de Pós-Graduação em Física Aplicada, Universidade Federal da Integração Latino-Americana（拉丁美洲一体化联邦大学应用物理学研究生项目）；Departamento de Física, Universidade Federal do Espírito Santo, Núcleo de Astrofísica e Cosmologia (Cosmo-Ufes)（圣埃斯皮里图联邦大学物理系天体物理与宇宙学中心）
Simulating the LOcal Web (SLOW): VII. Intergalactic magnetic field models for multi-messenger applications
Ludwig-Maximilians-Universität München（慕尼黑大学）；Excellence Cluster ORIGINS（ORIGINS卓越集群）；Max-Planck-Institut für Astrophysik（马克斯·普朗克天体物理学研究所）；Max-Planck-Institut für Physik（马克斯·普朗克物理研究所）；Institutt for fysikk, NTNU（挪威科技大学物理系）；The University of Chicago（芝加哥大学）；Univ. Lille, CNRS, Centrale Lille, UMR 9189 CRIStAL（里尔大学）；Université Paris-Saclay（巴黎萨克雷大学）
The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) is designed to observe cosmic neutrinos (CNs) above 20 PeV and ultra-high energy cosmic rays (UHECRs) above 20 EeV over the full sky. The POEMMA mission calls for two identical satellites flying in loose formation, each comprised of a 4-meter wide field-of-view (45 degrees) Schmidt photometer. The hybrid focal surface includes a fast (1 $μ$s) ultraviolet camera for fluorescence observations and an ultrafast (10 ns) optical camera for Cherenkov observations. POEMMA will provide new multi-messenger windows onto the most energetic events …
In this paper we review the extragalactic propagation of ultrahigh energy cosmic-rays (UHECR). We present the different energy loss processes of protons and nuclei, and their expected influence on energy evolution of the UHECR spectrum and composition. We discuss the possible implications of the recent composition analyses provided by the Pierre Auger Observatory. The influence of extragalactic magnetic fields and possible departures from the rectilinear case are also mentioned as well as the production of secondary cosmogenic neutrinos and photons and the constraints their observation would i…
Hadronic origin of gamma rays and neutrinos from blazars: Multi-messenger implications and observational constraints
Universidade Estadual de Londrina (UEL)（隆德里纳州立大学）；Universidade Federal de São Carlos (UFSCar)（圣卡洛斯联邦大学）；Universidade Tecnológica Federal do Paraná (UTFPR)（巴拉那联邦技术大学）；Universidade Federal da Integração Latino-Americana（拉丁美洲一体化联邦大学）；Universidade Federal do Espírito Santo（圣埃斯皮里图联邦大学）
The scientific achievements of the Pierre Auger Collaboration cover diverse and complementary fields of research. The search for the origin of ultra-high energy cosmic rays (UHECRs) is based on the measurement of the energy spectrum and mass composition of the primaries, on studies of multi-messengers, and on extensive anisotropy searches. With the collected data it is also possible to explore the characteristics of hadronic interactions at energies unreachable at human-made accelerators, and to assess the existence of non-standard physics effects. A selection of the latest results is presente…
Multi-messenger signal from QCD-Axion Ultracompact Minihalos
Institut de Fìsica d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology（高能物理研究所，巴塞罗那科技研究院）；Facultad de Ingeniería, Universidad San Sebastián（圣塞巴斯蒂安大学工程学院）；Departamento de Ciencias Físicas, Universidad Andrés Bello（安德斯贝略大学物理科学系）
The multi-messenger anomalies, including spectral hardening or excess for nuclei, leptons, ratios of $\bar p/p$ and B/C, and anisotropic reversal, were observed in past years. AMS-02 experiment also revealed different spectral break for positron and electron at 284 GeV and beyond TeV respectively. It is natural to ask whether all those anomalies originate from one unified physical scenario. In this work, the spatially-dependent propagation (SDP) with a nearby SNR source is adopted to reproduce above mentioned anomalies. There possibly exists dense molecular cloud(DMC) around SNRs and the secon…
Multi-messenger astrophysics, a long-anticipated extension to traditional and multiwavelength astronomy, has recently emerged as a distinct discipline providing unique and valuable insights into the properties and processes of the physical universe. These insights arise from the inherently complementary information carried by photons, gravitational waves, neutrinos, and cosmic rays about individual cosmic sources and source populations. Realizing the observation of astrophysical sources via non-photonic messengers has presented enormous challenges, as evidenced by the fiscal and physical scale…
Almost three decades ago, the Fly's Eye experiment recorded the most energetic cosmic-ray ever observed. With an energy of 320 EeV, this event is well beyond the suppression region of the ultra-high energy cosmic rays (UHECR) spectrum. Modern and larger observatories, with an exposure up to 60 times larger, have never observed an event with even remotely comparable energy. Thus, if the energy of the Fly's Eye event was indeed well measured, as strongly suggested by the data, then it remains a great mystery or an unbelievable stroke of luck. At such high energies, the Universe is very opaque to…
The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) mission is being designed to establish charged-particle astronomy with ultra-high energy cosmic rays (UHECRs) and to observe cosmogenic tau neutrinos (CTNs). The study of UHECRs and CTNs from space will yield orders-of-magnitude increase in statistics of observed UHECRs at the highest energies, and the observation of the cosmogenic flux of neutrinos for a range of UHECR models. These observations should solve the long-standing puzzle of the origin of the highest energy particles ever observed, providing a new window onto the most energ…
Observational strategies for ultrahigh-energy neutrinos: the importance of deep sensitivity for detection and astronomy
Sorbonne Université（索邦大学）；CNRS（法国国家科学研究中心）；Institut d’Astrophysique de Paris（巴黎天体物理研究所）；Vrije Universiteit Brussels（布鲁塞尔自由大学）；The Pennsylvania State University（宾夕法尼亚州立大学）；Universite Paris Diderot（巴黎第七大学）；Laboratoire de Physique Nucleaire et de Hautes Energies（核物理与高能物理实验室）；Center for Multimessenger Astrophysics（多信使天文学中心）；Institute for Gravitation and the Cosmos（引力与宇宙研究所）
A Multi-messenger Search for Ultra-high-energy Gamma Rays in Coincidence with Neutrinos
Instituto de Física, Universidad Nacional Autónoma de México（墨西哥国立自治大学物理研究所）；Universidad Autónoma de Chiapas（恰帕斯自治大学）；Instituto de Astronomía, Universidad Nacional Autónoma de México（墨西哥国立自治大学天文学研究所）；Universidad de Costa Rica（哥斯达黎加大学）；Universidad Michoacana de San Nicolás de Hidalgo（米却肯圣尼古拉斯德伊达尔戈大学）；Temple University（天普大学）；Department of Physics and Astronomy, Michigan State University（密歇根州立大学物理与天文学系）；Instituto Nacional de Astrofísica, Óptica y Electrónica（国家天体物理学、光学和电子学研究所）
Kerr black holes are energetically similar to spinning tops accompanied by frame dragging in the surrounding spacetime. Frame dragging is shown herein to be a universal causal agent for producing multi-messenger emissions. We discuss high energy emissions produced by gravitational spin-orbit coupling along the axis of rotation and low energy emissions from surrounding matter via a torus magnetosphere. Model results point to ultra-high energy cosmic rays (UHECRs) from supermassive black holes at about the Greisen-Zatsepin-Kuzmin (GZK) energy threshold from low-luminosity active galactic nuclei …
The propagation trajectories of ultra-high-energy cosmic rays (UHECRs) are inevitably affected by Galactic magnetic field (GMF). Because of the inevitability, the importance of the studies of the propagation in GMF have increased to interpret the results of recent UHECR experiments. This article reviews the effects of GMF to the propagation and arrival directions of UHECRs and introduces recent studies to constrain UHECR sources.
The next generation of ultra-high energy cosmic ray (UHECR) and very-high energy neutrino observatories will address the challenge of the extremely low fluxes of these particles at the highest energies. EUSO-SPB2 (Extreme Universe Space Observatory on a Super Pressure Balloon2) is designed to prepare space missions to address this challenge. EUSO-SPB2 is equipped with 2 telescopes: the Fluorescence Telescope, which will point downwards and measure fluorescence emission from UHECR air showers with an energy above 2EeV, and the Cherenkov Telescope (CT), which will point towards the Earth's limb …
Mixed fermion-boson stars are stable, horizonless, everywhere regular solutions of the coupled Einstein-(complex, massive) Klein-Gordon-Euler system. While isolated neutron stars and boson stars are uniquely determined by their central energy density, mixed configurations conform an extended parameter space that depends on the combination of the number of fermions and (ultra-light) bosons. The wider possibilities offered by fermion-boson stars could help explain the tension in the measurements of neutron star masses and radii reported in recent multi-messenger observations and nuclear-physics …
The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) is a NASA Astrophysics probe-class mission designed to observe ultra-high energy cosmic rays (UHECRs) and cosmic neutrinos from space. Astro2020 APC white paper: Medium-class Space Particle Astrophysics Project.
We examine the potential multi-messenger role of BL Lac objects emitting at high energy (so-called HBL) focusing on the limits on the energy density of soft radiation in the jet frame, a critical parameter which regulates the proton cooling and the fragmentation of ultra-high energy cosmic ray (UHECR) nuclei possibly accelerated in the jet. We show that (under the assumption that the high-energy emission bump is dominated by inverse Compton emission) the energy density of any external soft radiation field (e.g. produced by a layer surrounding the jet or in the accretion flow) cannot be larger …
A new model for the continuum spectra of AM CVn binaries and multi-messenger inference with normalizing flows
University of Manitoba（曼尼托巴大学）；Winnipeg Institute for Theoretical Physics（温尼伯理论物理研究所）；University of Texas Rio Grande Valley（德克萨斯大学里奥格兰德河谷分校）；South Texas Space Science Institute（南德克萨斯空间科学研究所）；Carnegie Mellon University（卡内基梅隆大学）；Texas Tech University（德克萨斯理工大学）；Flatiron Institute（平顿研究所）
The TeV gamma-ray source MGRO J1908+06 is one of the highest-energy sources known, with observed emission by the High Altitude Water Cherenkov (HAWC) Observatory extending well past 100 TeV. The source exhibits both energy-dependent morphology and a spatially-dependent spectral index. The emission is likely to be dominantly leptonic, and associated with the radio-quiet PSR J1907+0602. However, one-population models do not describe the data well; a second particle population is needed to explain the shape of the spectral energy distribution at the highest energies. This component can be well-de…
IceCube detects more than 100,000 neutrinos per year in the GeV- to PeV-energy range. Among those, we have isolated a flux of high-energy cosmic neutrinos. I will discuss the instrument, the analysis of the data, the significance of the discovery of cosmic neutrinos, and the recent multi-messenger observation of a flaring TeV blazar in coincidence with the IceCube neutrino alert IC170922.
