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Updated: Nov 7, 2025
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Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses
Published on: July 2, 2012
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X-ray quasi-periodic eruptions from two previously quiescent galaxies.
R Arcodia1, A Merloni2, K Nandra2
1Max-Planck-Institut für Extraterrestrische Physik, Garching, Germany. arcodia@mpe.mpg.de.
Nature
|April 29, 2021
Summary
Quasi-periodic eruptions (QPEs) are X-ray bursts from supermassive black holes. New observations reveal QPEs can occur without active galactic nuclei, suggesting an orbiting compact object may trigger these events.
Area of Science:
- Astrophysics
- High-energy astrophysics
- Black hole physics
Background:
- Quasi-periodic eruptions (QPEs) are high-amplitude X-ray bursts from galactic nuclei.
- Previously, only two QPE sources were known, both associated with active galactic nuclei.
Purpose of the Study:
- To search for and characterize new Quasi-periodic eruptions (QPEs) sources.
- To investigate the conditions and potential triggers for QPEs.
Main Methods:
- Conducted a blind, systematic X-ray sky survey.
- Analyzed optical spectra of host galaxies.
- Compared QPE properties with existing theoretical models.
Main Results:
- Discovered QPEs in two additional galaxies.
- These host galaxies show no signs of active galactic nuclei activity.
- Observed QPE properties challenge current accretion disk instability models.
Conclusions:
- QPEs do not require a pre-existing active galactic nucleus.
- An orbiting compact object is a potential trigger mechanism for QPEs.
- QPEs could be electromagnetic counterparts to extreme-mass-ratio inspirals.
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