Francesca Bo.My very sober demeanor at the upcoming Km3NeT announcement. Let's ignore the 2 big spoilers I found on arXiv astro-ph.HE in the last 3 days.
YouTube
A consultare il bot di arXiv astro-ph.HE ci sono almeno due gruppi di ricerca che hanno fatto uno spoilerone nell'ultimo paio di giorni (e la stessa collaborazione di km3NeT all'ultima ICRC). Chissà se è così, o se arriverà una bella sorpresa!
https://mastodon.uno/@andreabettini/113990750841615306
#km3net #neutrini #astrofisica #astroparticelle #astroparticellare #RaggiCosmici #UHECR
Andrea Bettini (@[email protected])
Nel pomeriggio la collaborazione scientifica KM3NeT presenterà il risultato di una straordinaria osservazione realizzata da un telescopio sottomarino per neutrini al largo della Sicilia. Aggiornamenti su RaiNews24. Qui dalle 16.40 la diretta streaming dell'INFN https://www.youtube.com/live/Scmxmt_8t0M
Daniel Pomarèdein the #arXiv
Closing the net on transient sources of ultra-high-energy cosmic rays
by Sullivan Marafico and co-authors
https://arxiv.org/abs/2405.17179
#uhecr #cosmicrays #cosmography #universe #galaxies #astronomy #astrophysics #astrodon
Closing the net on transient sources of ultra-high-energy cosmic rays
Arrival directions of ultra-high-energy cosmic rays (UHECRs) observed above $4\times10^{19}\,$eV provide evidence of localized excesses that are key to identifying their sources. We leverage the 3D matter distribution from optical and infrared surveys as a density model of UHECR sources, which are considered to be transient. Agreement of the sky model with UHECR data imposes constraints on both the emission rate per unit matter and the time spread induced by encountered turbulent magnetic fields. Based on radio measurements of cosmic magnetism, we identify the Local Sheet as the magnetized structure responsible for the kiloyear duration of UHECR bursts for an observer on Earth and find that the turbulence amplitude must be within $0.5-20\,$nG for a coherence length of $10\,$kpc. At the same time, the burst-rate density must be above $50\,$Gpc$^{-3}\,$yr$^{-1}$ for Local-Sheet galaxies to reproduce the UHECR excesses and below $5\,000\,$Gpc$^{-3}\,$yr$^{-1}$ ($30\,000\,$Gpc$^{-3}\,$yr$^{-1}$) for the Milky Way (Local-Group galaxies) not to outshine other galaxies. For the transient emissions of protons and nuclei to match the energy spectra of UHECRs, the kinetic energy of the outflows responsible for UHECR acceleration must be below $4\times10^{54}\,$erg and above $5\times10^{50}\,$erg ($2\times10^{49}\,$erg) if we consider the Milky Way (or not). The only stellar-sized transients that satisfy both Hillas' and our criteria are long gamma-ray bursts.