Gamma-ray flares from pulsar wind nebulae in the Large Magellanic Cloud

Abstract

High-energy radiation of young pulsar wind nebulae (PWNe) is known to be variable. This is most prominently exemplified by the Crab nebula which can undergo both rapid brightenings and dimmings. Two pulsars in the Large Magellanic Cloud, PSR J0540-6919 and PSR J0537-6910 are evolutionally very close to Crab, so one may expect the same kind of variability from the PWNe around them as from the Crab nebula. In this work we search for variability in these PWNe in gamma rays using the data from the Fermi Large Area Telescope in the range 100 MeV-10 GeV collected from August 2008 to December 2021. We construct light curves of these sources in the three bands, 100-300 MeV, 300-1000 MeV and 1-10 GeV with the one week time resolution. We find evidence of flaring activity in all the bands, in contrast with Crab, where no flares at $E>1$ GeV were observed. Analysis of the flaring episode in the 100-300 and 300-1000 MeV bands indicates that the flux of one of the PWNe could grew by a factor of $\approx 5-10$. We are not confident about which of the two PWNe flared because of their proximity in the sky. However, in the 1-10 GeV band where the angular resolution of the LAT is better, we find several episodes of enhanced brightness in both the PWNe. We check possible contaminants which could be responsible for the observed variability, but find their contribution not to be relevant.

arXiv comment7 pages, 6 figures

References in corpus (20)

• Fermi Large Area Telescope Fourth Source Catalog
• The Evolution and Structure of Pulsar Wind Nebulae
• Gamma-ray Activity in the Crab Nebula: The Exceptional Flare of April 2011
• When A Standard Candle Flickers
• Observations of the Large Magellanic Cloud with Fermi
• Variability of the Vela Pulsar-wind Nebula Observed with Chandra
• Fermi Large Area Telescope Fourth Source Catalog Data Release 2
• The Crab Nebula's Wisps in Radio and Optical
• Deep Chandra Observation of the Pulsar Wind Nebula Powered by the Pulsar J1846-0258 in the Supernova Remnant Kes 75
• Long-term timing and emission behavior of the young Crab-like pulsar PSR B0540-69
• The brightening of the pulsar wind nebula of PSR B0540--69 after its spin-down rate transition
• Expansion and Brightness Changes in the Pulsar-Wind Nebula in the Composite Supernova Remnant Kes 75
• A New, Low Braking Index For the LMC Pulsar B0540-69
• Discovery of a Spin-Down State Change in the LMC Pulsar B0540-69
• Timing six energetic rotation-powered X-ray pulsars, including the fast-spinning young PSR J0058-7218 and Big Glitcher PSR J0537-6910
• The first ultraviolet detection of the Large Magellanic Cloud pulsar PSR B0540-69 and its multi-wavelength properties
• X-ray/GeV emissions from Crab-like pulsars in LMC
• The Variable Pulsar Wind Nebula of PSR J1809-1917
• Gamma-ray flux depressions of the Crab nebula in the high-energy range
• A systematic study of $\gamma$-ray flares from the Crab Nebula with Fermi-LAT: I. flare detection

Cited by in corpus (1)

• A Very-High-Energy Gamma-Ray View of the Transient Sky