The Origin of Ionized Filaments Within the Orion-Eridanus Superbubble

Abstract

The Orion-Eridanus superbubble, formed by the nearby Orion high mass star-forming region, contains multiple bright H$\alpha$ filaments on the Eridanus side of the superbubble. We examine the implications of the H$\alpha$ brightnesses and sizes of these filaments, the Eridanus filaments. We find that either the filaments must be highly elongated along the line of sight or they cannot be equilibrium structures illuminated solely by the Orion star-forming region. The Eridanus filaments may, instead, have formed when the Orion-Eridanus superbubble encountered and compressed a pre-existing, ionized gas cloud, such that the filaments are now out of equilibrium and slowly recombining.

arXiv comment11 pages, 2 figures, accepted by MNRAS, minor grammatical changes

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Cited by in corpus (9)

• Nested shells reveal the rejuvenation of the Orion-Eridanus superbubble
• 3D dynamics of the Orion cloud complex -- Discovery of coherent radial gas motions at the 100-pc scale
• 3D Dust Mapping Reveals that Orion Forms Part of a Large Ring of Dust
• Gas shells and magnetic fields in the Orion-Eridanus superbubble
• Interacting Large-Scale Magnetic Fields and Ionised Gas in the W50/SS433 System
• Kompaneets Model Fitting of the Orion-Eridanus Superbubble II: Thinking Outside of Barnard's Loop
• Kompaneets Model Fitting of the Orion-Eridanus Superbubble
• Ionized filaments and ongoing physical processes in massive star-forming sites around l = 345.5 degree
• Low-Frequency Carbon Recombination Lines in the Orion Molecular Cloud Complex