A galactic microquasar mimicking winged radio galaxies

Area of Science:

• * Astronomy and Astrophysics
• * Radio Astronomy
• * Extragalactic Astronomy

Background:

• * Winged radio galaxies are extragalactic radio sources with low-surface-brightness lobes misaligned with their main radio axis, posing a long-standing puzzle.
• * Existing models for wing formation in these galaxies lack definitive observational support.
• * Microquasars, galactic-scale analogues of quasars, offer a unique laboratory to study astrophysical jet phenomena.

Purpose of the Study:

• * To investigate the radio emission morphology of the Galactic microquasar GRS 1758-258.
• * To explore potential analogies between microquasar jet structures and extragalactic winged radio galaxies.
• * To test competing models for the formation of wing-like features in radio sources.

Main Methods:

• * High-resolution radio observations of the Galactic microquasar GRS 1758-258.
• * Morphological analysis of parsec-scale radio jets and extended emission.
• * Comparison of observed features with known winged radio galaxy structures.

Main Results:

• * Discovery of Z-shaped radio emission in the microquasar GRS 1758-258, unprecedented for such objects.
• * Strong morphological resemblance between the microquasar's emission and X/Z-shaped winged radio galaxies.
• * Observational data strongly support the hydrodynamic backflow model for feature formation.

Conclusions:

• * The Z-shaped emission in GRS 1758-258 provides the first direct analogy to winged radio galaxies within our own galaxy.
• * Hydrodynamic backflow is favored as the primary mechanism responsible for generating these peculiar radio structures.
• * This mechanism is likely applicable to understanding wing formation in numerous extragalactic winged radio galaxies.