Searching for TeV gamma-ray emission from SGR\,1935+2154 during its 2020 X-ray and radio bursting phase

Abstract

Magnetar hyperflares are the most plausible explanation for fast radio bursts (FRB) -- enigmatic powerful radio pulses with durations of several milliseconds and high brightness temperatures. The first observational evidence for this scenario was obtained in 2020 April when a FRB was detected from the direction of the Galactic magnetar and soft gamma-ray repeater SGR\,1935+2154. The FRB was preceded by two gamma-ray outburst alerts by the BAT instrument aboard the Swift satellite, which triggered follow-up observations by the High Energy Stereoscopic System (H.E.S.S.). H.E.S.S. has observed SGR\,1935+2154 for 2 hr on 2020 April 28. The observations are coincident with X-ray bursts from the magnetar detected by INTEGRAL and Fermi-GBM, thus providing the first very high energy (VHE) gamma-ray observations of a magnetar in a flaring state. High-quality data acquired during these follow-up observations allow us to perform a search for short-time transients. No significant signal at energies $E>0.6$~TeV is found and upper limits on the persistent and transient emission are derived. We here present the analysis of these observations and discuss the obtained results and prospects of the H.E.S.S. follow-up program for soft gamma-ray repeaters.

arXiv commentReceived 2021 June 13; accepted 2021 June 28; published 2021 September 29

References in corpus (38)

• Magnetars
• Observations of the Crab Nebula with H.E.S.S
• A bright millisecond-duration radio burst from a Galactic magnetar
• Limits and Confidence Intervals in the Presence of Nuisance Parameters
• Fast Radio Bursts
• FRBCAT: The Fast Radio Burst Catalogue
• A model for fast extragalactic radio bursts
• Fast radio bursts as synchrotron maser emission from decelerating relativistic blast waves
• The Fermi GBM Gamma-Ray Burst Spectral Catalog: Four Years Of Data
• The Giant Flare of 1998 August 27 from SGR 1900+14: II. Radiative Mechanism and Physical Constraints on the Source
• Background Modelling in Very-High-Energy gamma-ray Astronomy
• INTEGRAL discovery of a burst with associated radio emission from the magnetar SGR 1935+2154
• A high performance likelihood reconstruction of gamma-rays for Imaging Atmospheric Cherenkov Telescopes
• The Fourth Fermi-GBM Gamma-Ray Burst Catalog: A Decade of Data
• The Physical Mechanisms of Fast Radio Bursts
• A flaring magnetar in FRB 121102?
• HXMT Identification of a non-thermal X-ray burst from SGR J1935+2154 and with FRB 200428
• The 2nd Fermi GBM Gamma-Ray Burst Catalog: The First Four Years
• The 3rd Fermi GBM Gamma-Ray Burst Catalog: The First Six Years
• Blast Waves from Magnetar Flares and Fast Radio Bursts
• A Monte Carlo Template based analysis for Air-Cherenkov Arrays
• A peculiar hard X-ray counterpart of a Galactic fast radio burst
• No pulsed radio emission during a bursting phase of a Galactic magnetar
• Detection of two bright radio bursts from magnetar SGR 1935+2154
• A polarized fast radio burst at low Galactic latitude
• Burst properties of the most recurring transient magnetar SGR J1935+2154
• Fermi/GBM View of the 2019 and 2020 Burst Active Episodes of SGR J1935+2154
• Revisiting the distance, environment and supernova properties of SNR G57.2+0.8 that hosts SGR 1935+2154
• TeV-PeV Neutrinos from Giant Flares of Magnetars and the Case of SGR 1806-20
• Constraining very-high-energy and optical emission from FRB 121102 with the MAGIC telescopes
• The first observation of an intermediate flare from SGR 1935+2154
• The X-ray reactivation of the radio bursting magnetar SGR 1935+2154
• Multi-frequency observations of SGR J1935+2154
• Opacities for Photon Splitting and Pair Creation in Neutron Star Magnetospheres
• Extended VHE gamma-ray emission towards SGR1806-20, LBV1806-20, and stellar cluster Cl*1806-20
• Observations of the magnetars 4U 0142+61 and 1E 2259+586 with the MAGIC telescopes
• First limits on the very-high energy gamma-ray afterglow emission of a fast radio burst: H.E.S.S. observations of FRB 150418
• Analysis methods to search for transient events in ground-based Very High Energy gamma-ray astronomy

Cited by in corpus (8)

• The H.E.S.S. transients follow-up system
• A MeerKAT, e-MERLIN, H.E.S.S. and Swift search for persistent and transient emission associated with three localised FRBs
• Galactic transient sources with the Cherenkov Telescope Array Observatory
• A search using GEO600 for gravitational waves coincident with fast radio bursts from SGR 1935+2154
• An updated view and perspectives on high-energy gamma-ray emission from SGR J1935+2154 and its environment
• A Very-High-Energy Gamma-Ray View of the Transient Sky
• H.E.S.S.: The High Energy Stereoscopic System
• H.E.S.S. programme searching for VHE gamma rays associated with FRBs