Related papers: Neutrino lighthouse powered by Sagittarius A* disk…
I show that the high energy neutrino flux predicted to arise from AGN cores can explain the PeV neutrinos detected by Ice Cube without conflicting with the constraints from the observed extragalactic cosmic ray and gamma-ray backgrounds.
We estimate the fluxes of very high energy (VHE) gamma-rays and neutrinos from the Galactic Center which are by-products of the hadronic interactions between primary protons which are accelerated up to $\sim 10^{19}$eV and ambient matter.…
We present a search in IceCube data for neutrino emission from Galactic TeV gamma-ray sources detected by the HAWC gamma-ray observatory. HAWC serves as the excellent instrument to complement IceCube with its energy range extending to very…
We investigate the consequences of acceleration of nuclei in jets of active galaxies not far from the surface of an accretion disk. The nuclei can be accelerated in the re-connection regions in the jet and/or at the jet boundary, between…
We consider the production of neutrinos in active galactic nuclei (AGN) through hadronic cascades. The initial, high energy nucleons are accelerated in a source above the accretion disk around the central black hole. From the source, the…
The Km3NET collaboration has recently reported the detection of a neutrino event with energy in excess of 100 PeV. This detection is in 2.5-3$\sigma$ tension with the upper limit on the neutrino flux at this energy imposed by IceCube and…
IceCube has discovered a flux of astrophysical neutrinos and presented evidence for the first neutrino sources, a flaring blazar known as TXS 0506+056 and the active galaxy NGC 1068. However, the sources responsible for the majority of the…
The detection of the high-energy neutrino IC-170922A in spatial (within the error region) and temporal flare activity correlation with the blazar TXS 0506+056 allowed these objects to be considered as progenitor sources of neutrinos.…
At the beginning of 2016, LIGO reported the first-ever direct detection of gravitational waves. The measured signal was compatible with the merger of two black holes of about 30 solar masses, releasing about 3 solar masses of energy in…
Solar flares convert magnetic energy into thermal and non-thermal plasma energy, the latter implying particle acceleration of charged particles such as protons. Protons are injected out of the coronal acceleration region and can interact…
The detection of an astrophysical flux of neutrinos in the TeV-PeV energy range by the IceCube observatory has opened new possibilities for the study of extreme cosmic accelerators. The apparent isotropy of the neutrino arrival directions…
The observed dark matter abundance in the Universe can be explained with non-thermal, heavy dark matter models. In order for dark matter to still be present today, its lifetime has to far exceed the age of the Universe. In these scenarios,…
The recent association between IC-170922A and the blazar TXS0506+056 highlights the importance of real-time observations for identifying possible astrophysical neutrino sources. Thanks to its near-100\% duty cycle, 4$\pi$ steradian field of…
The origin of cosmic high-energy neutrinos remains largely unexplained. For high-energy neutrino alerts from IceCube, a coincidence with time-variable emission has been seen for three different types of accreting black holes: (1) a…
We report on recent near-infrared (NIR) and X-ray observations of Sagittarius A* (Sgr A*), the electromagnetic manifestation of the ~4x10^6 solar masses super-massive black hole (SMBH) at the Galactic Center. The goal of these coordinated…
We show that the high-energy cosmic neutrinos seen by the IceCube Neutrino Observatory can be used to probe interactions between neutrinos and the dark sector that cannot be reached by current cosmological methods. The origin of the…
Active galactic nuclei (AGN) can accelerate protons to energies of $\sim$10-100 TeV, with secondary production of high-energy neutrinos. If the acceleration is driven by magnetized turbulence, the main properties of the resulting proton and…
We present the first comprehensive search for high-energy neutrino emission from high- and low-mass X-ray binaries conducted by IceCube. Galactic X-ray binaries are long-standing candidates for the source of Galactic hadronic cosmic rays…
The recent detection of TeV neutrino emission from the nearby active galaxy NGC 1068 by IceCube suggests that AGN could make a sizable contribution to the total high-energy cosmic neutrino flux. The absence of TeV gamma rays from NGC 1068,…
We introduce neutrino astronomy starting from the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. Although the discovery of cosmic rays dates back a century, we…