Publications de Andrii Neronov

Intergalactic magnetism in a γ -ray beam as a model of Porphyrion

We estimate the magnetic field in the jets of the recently discovered 7 Mpc long Porphyrion system. We used nondetection of the system in gamma-rays to derive a lower bound on the co-moving magnetic field strength at the level of 10 nG (comoving). This val ...

2025

Detection of the Geminga pulsar at energies down to 20 GeV with the LST-1 of CTAO

Andrii Neronov, Volodymyr Savchenko, Oleg Kalashev

Context. Geminga is the third gamma-ray pulsar firmly detected by imaging atmospheric Cherenkov telescopes (IACTs) after the Crab and the Vela pulsars. Most of its emission is expected at tens of giga-electronvolts, and, out of the planned telescopes of th ...

2025

GRB 221009A: Observations with LST-1 of CTAO and Implications for Structured Jets in Long Gamma-Ray Bursts

Andrii Neronov, Volodymyr Savchenko, Oleg Kalashev

GRB 221009A is the brightest gamma-ray burst (GRB) observed to date. Extensive observations of its afterglow emission across the electromagnetic spectrum were performed, providing the first strong evidence of a jet with a nontrivial angular structure in a ...

2025

Multimessenger signature of cosmic rays from the microquasar V4641 Sgr propagating along a Galactic magnetic field line

Andrii Neronov

The recently detected extended very-high-energy 𝛾-ray emission from the microquasar V4641 Sgr reveals a puzzling 200 parsec-long jetlike structure significantly misaligned with its radio jet. We propose that this 𝛾-ray structure is produced by high-energy ...

American Physical Society (APS)2025

Detection of RS Oph with LST-1 and modelling of its HE/VHE gamma-ray emission

Andrii Neronov, Volodymyr Savchenko, Oleg Kalashev

Context. The recurrent nova RS Ophiuchi (RS Oph) underwent a thermonuclear eruption in August 2021. In this event, RS Oph was detected by the High Energy Stereoscopic System (H.E.S.S.), the Major Atmospheric Gamma Imaging Cherenkov (MAGIC), and the first L ...

2025

Constraint on magnetized galactic outflows from LOFAR rotation measure data

Andrii Neronov

Outflows from galaxies that are driven by active galactic nuclei and star formation activity spread magnetic fields into the intergalactic medium. The importance of this process can be assessed using cosmological magnetohydrodynamical numerical modeling of ...

2024

Performance of the MAGIC stellar intensity interferometer and expansion to MAGIC + CTAO-LST1 stellar intensity interferometer

Andrii Neronov, Volodymyr Savchenko, Oleg Kalashev

A new generation of optical intensity interferometers are emerging in recent years taking advantage of the existing infrastructure of Imaging Atmospheric Cherenkov Telescopes (IACTs). The MAGIC SII (Stellar Intensity Interferometer) in La Palma, Spain, has ...

SPIE2024

The second data release from the European Pulsar Timing Array IV. Implications for massive black holes, dark matter, and the early Universe

Andrii Neronov, Ke Liu, Jun Wang, Jongmoon Jang, Jia Liu

The European Pulsar Timing Array (EPTA) and Indian Pulsar Timing Array (InPTA) collaborations have measured a low-frequency common signal in the combination of their second and first data releases, respectively, with the correlation properties of a gravita ...

EDP SCIENCES S A2024

Energy dependence of the knee in the cosmic-ray spectrum across the Milky Way

Andrii Neronov

The all-particle spectrum of cosmic rays measured at Earth has a kneelike feature around 4 PeV. A priori, it is not clear if this is a local feature specific to the Solar neighborhood in the Milky Way or if it is a generic property of the Galactic cosmic-r ...

AMER PHYSICAL SOC2024

Constraints on the intergalactic magnetic field from Fermi/LAT observations of the 'pair echo' of GRB 221009A

Andrii Neronov

Delayed 'pair-echo' signal from interactions of very-high-energy gamma rays in the intergalactic medium can be used for the detection of the intergalactic magnetic field (IGMF). We used the data of the Fermi/LAT telescope coupled with LHAASO observatory me ...

Edp Sciences S A2024

Neutrino signal from Cygnus region of the Milky Way

Andrii Neronov

Interactions of cosmic-ray protons and nuclei in their sources and in the interstellar medium produce "hadronic" 7-ray emission. Gamma rays can also be of "leptonic" origin, i.e., originating from high-energy electrons accelerated together with protons. It ...

American Physical Society2024

A detailed study of the very high-energy Crab pulsar emission with the LST-1

Andrii Neronov, Volodymyr Savchenko

Context. To date, three pulsars have been firmly detected by imaging atmospheric Cherenkov telescopes (IACTs). Two of them reached the TeV energy range, challenging models of very high-energy (VHE) emission in pulsars. More precise observations are needed ...

EDP SCIENCES S A2024

Resistively controlled primordial magnetic turbulence decay

Andrii Neronov

Context. Magnetic fields generated in the early Universe undergo turbulent decay during the radiation-dominated era. The decay is governed by a decay exponent and a decay time. It has been argued that the latter is prolonged by magnetic reconnection, which ...

EDP SCIENCES S A2024

A new method of reconstructing images of gamma-ray telescopes applied to the LST-1 of CTAO

Andrii Neronov, Volodymyr Savchenko, Oleg Kalashev

Context. Imaging atmospheric Cherenkov telescopes (IACTs) are used to observe very high-energy photons from the ground. Gamma rays are indirectly detected through the Cherenkov light emitted by the air showers they induce. The new generation of experiments ...

2024

Neutrino Signal from a Population of Seyfert Galaxies

Andrii Neronov

IceCube Collaboration has previously reported evidence for a neutrino signal from a Seyfert galaxy NGC 1068. This may suggest that all Seyfert galaxies emit neutrinos. To test this hypothesis, we identify the best candidate neutrino sources among nearby Se ...

Amer Physical Soc2024

Energy-dependent periodicities of LS I+61°303 in the GeV band

Andrii Neronov

LS I +61 degrees 303 is a rare representative of the gamma-ray binaries with a compact object known to be a pulsar. We report on the periodicity and spectral analysis of this source performed with more than 14 yr of Fermi/LAT data. The periodicity of LS I ...

2023

Hint for a TeV neutrino emission from the Galactic Ridge with ANTARES

Randoald Müller, Andrii Neronov, Javier García Hernández

Interactions of cosmic ray protons, atomic nuclei, and electrons in the interstellar medium in the inner part of the Milky Way produce γ-ray flux from the Galactic Ridge. If the γ-ray emission is dominated by proton and nuclei interactions, a neutrino flux ...

2023

The contribution of magnetized galactic outflows to extragalactic Faraday rotation

Andrii Neronov

Galactic outflows driven by star formation and active galactic nuclei blow bubbles into their local environments, causing galactic magnetic fields to be carried into intergalactic space. We explore the redshift-dependent effect of these magnetized bubbles ...

OXFORD UNIV PRESS2023

Modeling the propagation of very-high-energy gamma-rays with the CRbeam code: Comparison with CRPropa and ELMAG codes

Andrii Neronov

Context. Very-high-energy gamma-rays produce electron positron pairs in interactions with low-energy photons of extragalactic background light during propagation through the intergalactic medium. The electron-positron pairs generate secondary gamma-rays de ...

2023

Hadronic nature of high-energy emission from the Galactic ridge

Andrii Neronov

We show that the IceCube observation of the Galactic neutrino-flux component confirms the hint of detection of neutrinos from the Galactic ridge (the inner part of the Milky Way disk within the Galactic longitude IlI < 30(degrees)), previously reported by ...

American Physical Society2023