The joint analysis of anisotropy signals and chemical composition of ultra-high energy cosmic rays offers strong potential for shedding light on the sources of these particles. Following up on an earlier idea, this paper studies the anisotropies produced by protons of energy >E/Z, assuming that anisotropies at energy >E have been produced by nuclei of charge Z, which share the same magnetic rigidity. We calculate the number of secondary protons produced through photodisintegration of the primary heavy nuclei. Making the extreme assumption that the source does not inject any proton, we find that the source(s) responsible for anisotropies such as reported by the Pierre Auger Observatory should lie closer than ~20-30, 80-100 and 180-200 Mpc if the anisotropy signal is mainly composed of oxygen, silicon and iron nuclei respectively. A violation of this constraint would otherwise result in the secondary protons forming a more significant anisotropy signal at lower energies. Even if the source were located closer than this distance, it would require an extraordinary metallicity >120, 1600, 1100 times solar metallicity in the acceleration zone of the source, for oxygen, silicon and iron respectively, to ensure that the concomitantly injected protons not to produce a more significant low energy anisotropy. This offers interesting prospects for constraining the nature and the source of ultra-high energy cosmic rays with the increase in statistics expected from next generation detectors.

Constraints on the source of ultra-high energy cosmic rays using anisotropy vs chemical composition

The joint analysis of anisotropy signals and chemical composition of ultra-high-energy cosmic rays offers strong potential for shedding light on the sources of these particles. Following up on an earlier idea, this paper studies the anisotropies produced by protons of energy >E/Z, assuming that anisotropies at energy >E have been produced by nuclei of charge Z, which share the same magnetic rigidity. We calculate the number of secondary protons produced through photodisintegration of the primary heavy nuclei. Making the extreme assumption that the source does not inject any proton, we find that the source(s) responsible for anisotropies such as reported by the Pierre Auger Observatory should lie closer than ∼20-30, 80-100, and 180-200 Mpc if the anisotropy signal is mainly composed of oxygen, silicon, and iron nuclei, respectively. A violation of this constraint would otherwise result in the secondary protons forming a more significant anisotropy signal at lower energies. Even if the source were located closer than this distance, it would require an extraordinary metallicity ∼> 120, 1600, and 1100 times solar metallicity in the acceleration zone of the source, for oxygen, silicon, and iron, respectively, to ensure that the concomitantly injected protons do not produce a more significant low-energymore » anisotropy. This offers interesting prospects for constraining the nature and the source of ultra-high-energy cosmic rays with the increase in statistics expected from next-generation detectors.« less

Constraints on the source of ultra-high-energy cosmic rays using anisotropy versus chemical composition

Multi-messenger data suggest that radio galaxies (i.e. non-blazar active galaxies) are perhaps the most likely class of sources for the diffuse flux of high-energy neutrinos reported by the IceCube Collaboration. In this study, we consider the gamma-ray spectrum observed from four nearby radio galaxies (Centaurus A, PKS 0625-35, NGC 1275 and IC 310) and constrain the intensity and spectral shape of the emission injected from these sources, accounting for the effects of attenuation and contributions from electromagnetic cascades (initiated both within the radio galaxy itself and during extragalactic propagation). Assuming that this gamma-ray emission is generated primarily through the interactions of cosmic-ray protons with gas, we calculate the neutrino flux predicted from each of these sources. Although this scenario is consistent with the constraints published by the IceCube and ANTARES Collaborations, the predicted fluxes consistently fall within an order of magnitude of the current point source sensitivity. The prospects appear very encouraging for the future detection of neutrino emission from the nearest radio galaxies.

High-energy gamma rays and neutrinos from nearby radio galaxies

Active galactic nuclei (AGNs) are considered to be one of the most appropriate sources of ultra high energy cosmic rays (UHECRs, $E \gtrsim 10^{18} \mathrm{~eV}$). Radiogalaxy Virgo A (M87) in the centre of a cluster of galaxies Virgo Cluster (VC) can be a prominent source of UHECRs. We investigate the possible contribution of Virgo A and the VC to the flux of events with trans-GZK energies - extremely high energy cosmic rays (EHECRs) - from the recent Auger and Telescope Array (TA) data sets ($E > 52 \mathrm{~EeV}$ and $E > 57 \mathrm{~EeV}$, respectively). We simulate EHECR propagation from Virgo A and the VC taking into account their deflections in galactic (GMF) and extragalactic (EGMF) magnetic fields and show that there is no excess of EHECR arrival directions from images of Virgo A/VC at different EHECR rigidities. By means of event-by-event analysis we recover the extragalactic arrival directions of EHECR events detected by Auger and TA for representative set of nuclei H(p), He, N, Si, Fe, and find evidences of enhanced fluxes of N-Si-Fe EHECRs from the Local Filament and Hot/Cold Spot regions. The Local Filament with its enhanced magnetic field is an expected contributor to the UHECR flux as the closest to the Earth last scattering centre, whereas Hot/Cold Spot region is a part of a larger arc-like spot, possibly created by diffusively spreading jet of UHECRs, accelerated in the relativistic jet of Virgo A during a prominent nuclear outburst about 10 - 12 Myr ago.

Search for ultra high-energy cosmic rays from radiogalaxy Virgo A

High-Energy Gamma Rays and Neutrinos from Nearby Radio Galaxies

The propagation of ultra high energy cosmic rays in Galactic and extragalactic magnetic fields is investigated in the present paper. The motion of charged particles of different energies and chemical composition is simulated using different Galactic magnetic field models. Positions for the real sources of events registered at the Auger observatory are calculated taking into account the influence of both Galactic and extragalactic turbulent fields. The possibility of their correlation with the Centaurus A radio galaxy is analyzed.

Search of ultra high energy cosmic rays’ sources. FRI-radiogalaxy Centaurus A

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

V. V. Marchenko

Author Tools

Chat about Author

Papers

Search of ultra high energy cosmic rays’ sources. FRI-radiogalaxy Centaurus A