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Published on: October 9, 2020
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Time-resolved hadronic particle acceleration in the recurrent nova RS Ophiuchi
, F Aharonian1,2,3, F Ait Benkhali4
1Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2, Ireland.
Science (New York, N.Y.)
|March 10, 2022
Summary
Astronomers detected very-high-energy gamma rays from the recurrent nova RS Ophiuchi, confirming particle acceleration in stellar explosions. This finding supports hadronic emission models for cosmic ray origins.
Area of Science:
- Astrophysics
- High-energy astrophysics
- Cosmic ray physics
Background:
- Recurrent novae involve thermonuclear explosions on white dwarfs in binary systems.
- Accretion from a companion star fuels these explosions.
- Particle acceleration is theorized to occur via shocks between ejected material and stellar winds.
Purpose of the Study:
- To report the detection of very-high-energy (VHE) gamma rays from the recurrent nova RS Ophiuchi.
- To investigate the origin and mechanisms of particle energization in nova outbursts.
- To constrain theoretical models of particle acceleration and emission processes.
Main Methods:
- Observations of RS Ophiuchi using the High Energy Stereoscopic System (H.E.S.S.).
- Analysis of VHE gamma-ray emission up to one month post-outburst (2021).
- Comparison of temporal profiles with lower-energy gamma-ray emission.
Main Results:
- Detection of VHE gamma-ray signals from RS Ophiuchi following its 2021 outburst.
- VHE emission profile mirrors lower-energy gamma-ray emission, with a 2-day peak flux delay.
- Observations favor hadronic emission models over leptonic ones for particle energization.
Conclusions:
- Shocks within dense stellar winds are efficient sites for cosmic ray acceleration to very high energies.
- The study provides crucial observational constraints on time-dependent particle energization models.
- RS Ophiuchi serves as a key laboratory for studying extreme astrophysical particle acceleration.
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