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The Stochastic X-Ray Variability of the Accreting Millisecond Pulsar MAXI J0911-655In this work, I report on the stochastic X-ray variability of the 340 hertz accreting millisecond pulsar MAXI J0911-655. Analyzing pointed observations of the XMM-Newton and NuSTAR observatories, I find that the source shows broad band-limited stochastic variability in the 0.01-10 hertz range with a total fractional variability of approximately 24 percent root mean square timing residuals in the 0.4 to 3 kiloelectronvolt energy band that increases to approximately 40 percent root mean square timing residuals in the 3 to 10 kiloelectronvolt band. Additionally, a pair of harmonically related quasi-periodic oscillations (QPOs) are discovered. The fundamental frequency of this harmonic pair is observed between frequencies of 62 and 146 megahertz. Like the band-limited noise, the amplitudes of the QPOs show a steep increase as a function of energy; this suggests that they share a similar origin, likely the inner accretion flow. Based on their energy dependence and frequency relation with respect to the noise terms, the QPOs are identified as low-frequency oscillations and discussed in terms of the Lense-Thirring precession model.
Document ID
20170002247
Document Type
Reprint (Version printed in journal)
Authors
Bult, Peter (Universities Space Research Association Greenbelt, MD, United States)
Date Acquired
March 14, 2017
Publication Date
March 3, 2017
Publication Information
Publication: Astrophysical Journal
Volume: 837
Issue: 1 Article 61
Subject Category
Astronomy
Astrophysics
Report/Patent Number
GSFC-E-DAA-TN39881
Funding Number(s)
CONTRACT_GRANT: NNH15CO48B
Distribution Limits
Public
Copyright
Other
Keywords
ulsars: general { stars: neutron { X-rays: binaries { individual (MAXI J0911{655