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arXiv · 2505.16921

A NuSTAR study of quasi-periodic oscillations from the ultraluminous X-ray sources in M82

Hamza El Byad·Matteo Bachetti·Silvia Columbu·Giuseppe Rodriguez·Maura Pilia·Matthew J. Middleton·Dominic J Walton·Murray Brightman·Hannah Earnshaw·Karl Forster·Brian Grefenstette·Felix Fürst·Marianne Heida·Matteo Imbrogno·Eleonora Veronica Lai·Thomas Maccarone
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Abstract

The study of quasi-periodic oscillations in X-ray binaries provides valuable insights into the physics of accretion around compact objects. The M82 galaxy hosts two ultraluminous X-ray sources (ULXs), one of which is suspected to harbor an intermediate-mass black hole. Using 39 NuSTAR observations acquired between 2014--2024, we investigate the aperiodic X-ray variability in M82. In particular, we study in detail the evolution of the QPO from M82 X-1 in the range 20--300 mHz. We do not find additional timing features in the data, besides a frequent broad noise component at lower frequencies. The QPO behaves similarly to other classes of low-frequency oscillations in accreting compact objects, both black holes and neutron stars.

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Hamza El Byad, Matteo Bachetti, Silvia Columbu, Giuseppe Rodriguez, Maura Pilia, Matthew J. Middleton, Dominic J Walton, Murray Brightman, Hannah Earnshaw, Karl Forster, Brian Grefenstette, Felix Fürst, Marianne Heida, Matteo Imbrogno, Eleonora Veronica Lai, Thomas Maccarone. 2025-05-22. A NuSTAR study of quasi-periodic oscillations from the ultraluminous X-ray sources in M82. https://doi.org/10.3847/1538-4357%2Faded8a

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