12–23 Jul 2021
Online
Europe/Berlin timezone

High-energy and very high-energy gamma-ray emission from the magnetar SGR 1900+14 outskirts

14 Jul 2021, 18:00
1h 30m
04

04

Talk GAD | Gamma Ray Direct Discussion

Speaker

Vadym Voitsekhovskyi (Astronomical Observatory of Taras Shevchenko National University of Kyiv )

Description

Hypernova remnants (HNRs) and magnetar wind nebulae (MWNe), supported by new-born millisecond magnetars, as well as magnetar giant flares are promising PeVatron candidates and even potential sources of ultra high energy cosmic rays (UHECRs, E>10^{18} eV). Nonthermal high-energy (HE, E>100 MeV) and very high-energy (VHE, E>100 GeV) γ-ray emission from magnetars' outskirts should be an observed signature of CR acceleration processes. We investigate HE and VHE γ-ray emission from the vicinity of the magnetar SGR 1900+14 as one generated by cosmic rays accelerated in a (still undetected) magnetar-related Supernova remnant and/or MWN. Modelling of the observed HE (the extended Fermi-LAT source 4FGL J1908.6+0915e) and VHE (the extended H.E.S.S. source candidate HOTS J1907+091 and the point-like HAWC TeV source 3HWC J1907+085) γ-ray emission, spatially coincident with the magnetar SGR 1900+14, was carried out in the framework of hadronic and leptonic models. We show that the observed γ-ray emission of abovementioned sources may be explained by a magnetar-connected HNR and/or a MWN created by a new-born millisecond magnetar with a large rotational energy E_rot ≈ 10^{52} erg. We analyse also all presently available multi-band observational data concerning the magnetar SGR 1900+14 and its environment and justify their explanation in the model of Hypernova-like explosion of a SGR 1900+14 progenitor.

Keywords

Magnetars; particle acceleration; cosmic rays; Supernova remnants; pulsar wind nebulae; gama-rays; nonthermal radiation mechanisms

Subcategory Theoretical Results

Primary authors

Prof. Bohdan Hnatyk (Astronomical Observatory of Taras Shevchenko National University of Kyiv ) Vadym Voitsekhovskyi (Astronomical Observatory of Taras Shevchenko National University of Kyiv ) Dr Roman Hnatyk (Astronomical Observatory of Taras Shevchenko National University of Kyiv) Prof. Valery Zhdanov (Astronomical Observatory of Taras Shevchenko National University of Kyiv)

Presentation materials