Decadal brightening in the northeastern non-thermal filament of Cassiopeia A

Abstract

We present the decadal brightening of non-thermal emission flux in the northeastern filament of the young supernova remnant Cassiopeia A (Cas A), which highlights dynamic processes in the forward shock. This filament, characterized by the highest particle acceleration rate among Cas A's outer shells, offers an exceptional opportunity to investigate underlying astrophysical mechanisms. Since 2000, the non-thermal flux has increased by several tens of percent before plateauing, while the spectral shape has remained largely unchanged. Over the past two decades, the filament's morphology has evolved significantly, splitting into two distinct sections. Detailed analysis reveals contrasting behaviors: one section shows a flux increase followed by saturation, while the other maintains a steady flux. These differences likely arise from nonlinear effects, including magnetohydrodynamic interactions influenced by magnetic field orientation, interactions with surrounding material, and complex fluid dynamics associated with young supernova remnants. The localized evolution of this filament, captured with high spatial resolution, provides critical insights into the temporal dynamics of non-thermal particles and the generation of cosmic rays from asymmetric supernova explosions.

References in corpus (19)

• Asymmetries in core-collapse supernovae from maps of radioactive ${}^{44}$Ti in CassiopeiaA
• Observational constraints on energetic particle diffusion in young SNRs: amplified magnetic field and maximum energy
• The distribution of radioactive ${}^{44}$Ti in Cassiopeia A
• The Bubble-like Interior of the Core-Collapse Supernova Remnant Cassiopeia A
• Electron Surfing and Drift Accelerations in a Weibel-dominated High-Mach-number Shock
• Cosmic ray diffusion near the Bohm limit in the Cassiopeia A supernova remnant
• The Density and Mass of Unshocked Ejecta in Cassiopeia A through Low Frequency Radio Absorption
• A JWST Survey of the Supernova Remnant Cassiopeia A
• Evidence for past interaction with an asymmetric circumstellar shell in the young SNR Cassiopeia A
• X-ray polarization detection of Cassiopeia A with IXPE
• A Comparison of X-ray and Optical Emission in Cassiopeia A
• High-entropy ejecta plumes in Cassiopeia A from neutrino-driven convection
• When disorder looks like order: a new model to explain radial magnetic fields in young supernova remnants
• Richardson-Lucy deconvolution with a spatially Variant point-spread function of Chandra: Supernova Remnant Cassiopeia A as an Example
• Fast Particle Acceleration at Perpendicular Shocks with Uniform Upstream Magnetic Field and Strong Downstream Turbulence
• Enhanced Magnetic Field Amplification by Ion-Beam Weibel Instability in Weakly Magnetized Astrophysical Shocks
• Discovery of Stable Titanium at the Northeastern Jet of Cassiopeia A: Need for a Weak Jet Mechanism?
• Kinematics of Supernova Remnants Using Multiepoch Maximum Likelihood Estimation: Chandra Observation of Cassiopeia A as an Example
• On the origin of the asymmetry of the ejecta structure and explosion of G350.1$-$0.3