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Updated: Nov 25, 2025
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Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
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Interaction of SN Ib 2004dk with a Previously Expelled Envelope.
David Pooley1,2, J Craig Wheeler3, Jozsef Vinkó3,4,5
1Department of Physics and Astronomy, Trinity University, San Antonio, TX, USA.
The Astrophysical Journal
|December 16, 2020
Summary
We confirmed ejecta-circumstellar material interaction in supernova SN 2004dk, observing Hα emission years after its explosion. This provides new insights into pre-supernova mass-loss processes.
Area of Science:
- Astronomy and Astrophysics
- Supernova Remnants
- Stellar Evolution
Background:
- Observational evidence for supernova (SN) ejecta interacting with circumstellar material (CSM) is scarce.
- SN 2004dk, a Type Ib supernova, exhibited unusual Hα emission.
- This phenomenon is crucial for understanding the final stages of massive star evolution.
Purpose of the Study:
- To confirm and study the ejecta-CSM interaction in SN 2004dk.
- To investigate pre-supernova mass-loss processes using multi-wavelength observations.
- To model the circumstellar environment and its formation.
Main Methods:
- Narrowband Hα imaging and follow-up optical spectroscopy.
- Multi-wavelength observations using XMM-Newton, Swift, and Chandra X-ray Observatory.
- Development of a wind-bubble model to interpret the CSM structure.
Main Results:
- Confirmed ejecta-CSM interaction via a broad Hα component (FWHM ~ 290 km s⁻¹).
- Detected strong radio, X-ray, and Hα emission years post-explosion.
- Constrained pre-SN mass-loss, suggesting a shell ejected ~1400 years prior to explosion.
Conclusions:
- SN 2004dk provides a rare example of ejecta-CSM interaction.
- The CSM structure suggests a complex pre-SN mass-loss history, possibly involving wind interactions.
- The study offers insights into the late-time evolution of supernovae and their environments.
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