Related papers: Hadronic processes within collective stellar winds
The Cygnus region is a vast star-forming complex harbouring a population of powerful objects, including massive star clusters and associations, Wolf-Rayet stars, pulsars, and supernova remnants. The multi-wavelength picture is far from…
We discuss a specific population of galactic PeVatrons which may be the main source of the galactic cosmic-ray (CR) component well above PeV energies. Supernovae in compact clusters of massive stars are proposed as powerful sources of CRs,…
The central regions of galaxies are complex environments, rich in evolved and/or massive stars. For galaxies hosting an active galactic nucleus (AGN) with jets, the interaction of the jets with the winds of the stars within can lead to…
Gamma rays are the best probes to study high-energy particle interactions occurring in astrophysical environments. Space based instruments such as Fermi Large Area Telescope (Fermi LAT) and ground based experiments such as VERITAS, H.E.S.S.…
TeV photons from blazars at relatively large distances, interacting with the optical-IR cosmic background, are efficiently converted into electron-positron pairs. The produced pairs are extremely relativistic (Lorentz factors of the order…
Non-thermal particles and high-energy radiation can play a role in the dynamical processes in star-forming regions and provide an important piece of the multiwavelength observational picture of their structure and components. Powerful…
Recent observations show that hypernovae may deposit some fraction of their kinetic energy in mildly relativistic ejecta. In the dissipation process of such ejecta in a stellar wind, cosmic ray protons can be accelerated up to $\sim…
Pulsar wind nebulae (PWNe), formed when the wind originating from a rapidly rotating neutron star flows out into its surroundings, have now been observed across the electromagnetic spectrum from the radio to the PeV gamma-ray regime. For…
In this work, we reanalyzed 11 years of spectral data from the \textit{Fermi} Large Area Telescope (\textit{Fermi}-LAT) of currently observed starburst galaxies (SBGs) and star-forming galaxies (SFGs). We used a one-zone model provided by…
The nearby Orion-Eridanus superbubble, which was blown by multiple supernovae several Myr ago, has likely produced cosmic rays. Its turbulent medium, still energised by massive stars, can impact cosmic-ray transport locally. The gamma rays…
Young pulsars produce relativistic winds which interact with matter ejected during the supernova explosion and the surrounding interstellar gas. Particles are accelerated to very high energies somewhere in the pulsar winds or at the shocks…
The HEGRA Cherenkov telescope array group recently reported a steady and extended unidentified TeV gamma-ray source lying at the outskirts of Cygnus OB2. This is the most massive stellar association known in the Galaxy, estimated to contain…
General physics of very high energy hadronic interactions is discussed. Special attention is payed to the contribution of semihard processes to the interaction dynamics and to the role of parton shadowing and parton density saturation. In…
Astrospheres and wind bubbles of massive stars are believed to be sources of cosmic rays with energies $E\lesssim 1\,$TeV. These particles are not directly detectable, but their impact on surrounding matter, in particular ionisation of…
The supersonic winds produced by massive stars carry a large amount of kinetic power. In numerous scenarios such winds have been proven to produce shocks in which relativistic particles are accelerated emitting non-thermal radiation. Here,…
Cosmic rays of energies up to a few PeV are believed to be of galactic origin, yet individual sources have still not been firmly identified. Due to inelastic collisions with the interstellar gas, cosmic-ray nuclei produce a diffuse flux of…
Stars and their winds can contribute to the non-thermal (NT) emission in extragalactic jets. Given the complexity of jet-star interactions, the properties of the resulting emission are strongly linked to those of the emitting flows. We…
The central parsec of the Galaxy contains dozens of massive stars with a cumulative mass loss rate of ~ 10^{-3} solar masses per year. Shocks among these stellar winds produce the hot plasma that pervades the central part of the galaxy. We…
We have analysed the observable consequences of the interactions of spin-1 resonances coupled to the invariant fermionic currents that arise in an $SO(5)$ Composite Higgs set-up. The phenomenology entailed by such interactions is thoroughly…
Dense stellar winds may mass-load the jets of active galactic nuclei, although it is unclear what are the time and spatial scales in which the mixing takes place. We study the first steps of the interaction between jets and stellar winds,…