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Published on: May 9, 2020
A transient radio jet in an erupting dwarf nova
Elmar Körding1, Michael Rupen, Christian Knigge
1School of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, UK. elmar@phys.soton.ac.uk
Science (New York, N.Y.)
|June 7, 2008
Summary
Astronomers detected the first astrophysical jet from a dwarf nova, a type of accreting white dwarf. This discovery suggests that the disc/jet coupling mechanism is common across all accreting celestial objects.
Area of Science:
- Astrophysics
- Stellar Evolution
- Plasma Physics
Background:
- Astrophysical jets are observed in various accreting objects, including supermassive black holes and young stellar objects.
- A unified disc/jet coupling scenario, primarily based on X-ray binaries, has been widely accepted.
- Cataclysmic variables, specifically dwarf novae (weakly accreting white dwarfs), were considered exceptions due to the lack of detected jets despite similar outburst behaviors to X-ray binaries.
Purpose of the Study:
- To investigate the presence of astrophysical jets in dwarf novae.
- To determine if the disc/jet coupling mechanism observed in other accreting objects is also present in dwarf novae.
- To test the hypothesis that jet production is a ubiquitous phenomenon in accreting systems.
Main Methods:
- Conducted radio observations of a dwarf nova during its outburst phase.
- Analyzed the observed radio emission for characteristics indicative of synchrotron emission from a jet.
- Compared the properties of the inferred jet (power, relation to outburst cycle) with those observed in X-ray binaries.
Main Results:
- Detected variable flat-spectrum radio emission from the dwarf nova during outburst.
- Interpreted the radio emission as originating from a transient jet, consistent with synchrotron emission.
- Found that the inferred jet power and its relationship to the outburst cycle are analogous to those in X-ray binaries.
Conclusions:
- The detection of a jet in a dwarf nova challenges the notion that these systems are exceptions to jet production.
- The findings suggest that the disc/jet coupling mechanism is indeed ubiquitous, operating across a wide range of accreting objects.
- This study unifies the understanding of jet formation in diverse astrophysical environments, from stellar-mass objects to supermassive black holes.
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