Giant ringlike radio structures around galaxy cluster Abell 3376

Area of Science:

• Cosmology
• Astrophysics
• Radio Astronomy

Background:

• Large-scale structures assemble via hierarchical clustering in cold dark matter cosmology.
• Cosmic shock waves in supersonic intergalactic matter flows are crucial for structure formation.
• These shock waves occur on megaparsec (Mpc) scales, impacting galaxy clusters, filaments, and pancakes.

Purpose of the Study:

• To investigate the nature of giant, ring-shaped nonthermal radio-emitting structures observed at the outskirts of the Abell 3376 galaxy cluster.
• To determine if these structures are evidence of cosmological large-scale matter flow shock waves.
• To explore the potential of these structures as sites for cosmic-ray acceleration.

Main Methods:

• Utilized the Very Large Array (VLA) telescope for observations.
• Analyzed giant (approximately 2 Mpc by 1.6 Mpc) ring-shaped nonthermal radio-emitting structures.
• Interpreted observations within the framework of cold dark matter cosmology and supersonic intergalactic flows.

Main Results:

• Discovered giant, ring-shaped nonthermal radio structures near Abell 3376.
• These structures are approximately 2 Mpc by 1.6 Mpc in size.
• The observed structures are potentially linked to shock waves in large-scale cosmological matter flows.

Conclusions:

• The observed radio structures may represent elusive cosmic shock waves from large-scale matter flows.
• These shock waves possess sufficient energy to power the observed radio emission.
• The structures could be sites where magnetic shocks accelerate cosmic-ray particles to energies of 10^18 to 10^19 electron volts.