UHECR Maps: mysteries and surprises

TL;DR

This paper explores the mysteries of ultra-high-energy cosmic rays (UHECR), proposing that they are primarily light nuclei like helium, which explains various observational puzzles and suggests a new galactic component and implications for neutrino astronomy.

Contribution

It introduces a model where UHECR are mainly light nuclei, resolving contradictions in observations and supporting a potential new galactic UHECR component and Z-shower model.

Findings

UHECR are likely light nuclei, mainly helium.

The model explains Virgo suppression and Cen A clustering.

Hints of a new galactic UHECR component.

Abstract

The rise of nucleon UHECR above GZK astronomy made by protons is puzzled by three main mysteries: an unexpected nearby Virgo UHECR suppression, a rich crowded clustering frozen vertically (north-south) along Cen A, a composition suggesting nuclei and not nucleons. The UHECR map, initially consistent with GZK volumes, to day seem to be not much correlated with expected Super Galactic Plane. Moreover slant depth data of UHECR from AUGER airshower shape do not favor the proton but points to a nuclei, while HIRES, on the contrary favors mostly nucleons. We tried to solve the contradictions assuming UHECR as light nuclei (mostly He) spread by planar galactic fields, randomly at vertical axis. The He fragility and its mass and charge explains the Virgo absence (due to opacity above few Mpc) and the Cen A spread clustering (a quarter of the whole sample). However more events and rare doublets and clustering elsewhere are waiting for an answer. Here we foresee hint of new UHECR component: galactic ones. Moreover a careful updated views of UHECR sky over different (Radio,IR,Optics, X,gamma, TeV) background are also favoring forgotten revolutionary Z-shower model. Both Z-Shower, proton GZK and Lightest nuclei UHECR models have dramatic influence on expected UHE neutrino Astronomy: to be soon revealed by UHE tau neutrino induced air-showers in different ways.