The giant outburst of EXO 2030+375 I: Spectral and pulse profile evolution
arXiv:2405.20734 · doi:10.1051/0004-6361/202348594
Abstract
The Be X-ray binary EXO 2030+375 went through its third recorded giant outburst from June 2021 to early 2022. We present the results of both spectral and timing analysis based on NICER monitoring, covering the 2-10 keV flux range from 20 to 310 mCrab. Dense monitoring with observations carried out about every second day and a total exposure time of 160 ks allowed us to closely track the source evolution over the outburst. Changes in spectral shape and pulse profiles showed a stable luminosity dependence during the rise and decline. The same type of dependence has been seen in past outbursts. The pulse profile is characterized by several distinct peaks and dips. The profiles show a clear dependence on luminosity with a stark transition at a luminosity of 2x10^36 erg/s, indicating a change in the emission pattern. Using relativistic ray-tracing, we demonstrate how anisotropic beaming of emission from an accretion channel with constant geometrical configuration can give rise to the observed pulse profiles over a range of luminosities.
arXiv comment15 pages, 16 figures, accepted by A&A
References in corpus (42)
- Gaia Data Release 2. Summary of the contents and survey properties
- The Gaia mission
- Gaia Data Release 3: Summary of the content and survey properties
- On the Absorption of X-rays in the Interstellar Medium
- Atomic Data for Astrophysics. II. New Analytic Fits for Photoionization Cross Sections of Atoms and Ions
- Be/X-ray binaries
- Spectral Formation in Accreting X-Ray Pulsars: Bimodal Variation of the Cyclotron Energy with Luminosity
- The critical accretion luminosity for magnetized neutron stars
- Discovery of a flux-related change of the cyclotron line energy in Her X-1
- A reflection model for the cyclotron lines in the spectra of X-ray pulsars
- Accretion Onto Fast X-Ray Pulsars
- Patterns of variability in Be/X-ray pulsars during giant outbursts
- A Decade in the Life of EXO 2030+375: A Multi-wavelength Study of an Accreting X-ray Pulsar
- Outbursts Large and Small from EXO 2030+375
- On the dependence of the X-ray continuum variations with luminosity in accreting X-ray pulsars
- Positive correlation between the cyclotron line energy and luminosity in sub-critical X-ray pulsars: Doppler effect in the accretion channel
- Origin of Two Types of X-Ray Outbursts in Be/X-Ray Binaries. I. Accretion Scenarios
- Distribution of High-Mass X-ray Binaries in the Milky Way
- Distances to Galactic X-ray Binaries with Gaia DR2
- Luminosity-dependent changes of the cyclotron line energy and spectral hardness in Cep X-4
- Giant outburst of EXO 2030+375: pulse-phase resolved analysis of INTEGRAL data
- INTEGRAL and Swift observations of EXO 2030+375 during a giant outburst
- Decade long RXTE monitoring observations of Be/X-ray binary pulsar EXO 2030+375
- Timing and Spectral properties of Be/X-ray pulsar EXO 2030+375 during a Type I outburst
- Analyzing X-ray pulsar profiles: geometry and beam pattern of A 0535+26
- Accretion torque on magnetized neutron stars
- Dynamical and Radiative Properties of X-ray Pulsar Accretion Columns: Phase-Averaged Spectra
- X-ray polarimetry of X-ray pulsar X Persei: another orthogonal rotator?
- X-ray pulsar GRO J100857 as an orthogonal rotator
- Complex variations of X-ray polarization in the X-ray pulsar LS V +44 17/RX J0440.9+4431
- Spectral and Timing Analysis of the accretion-powered pulsar 4U 1626-67 observed with Suzaku and NuSTAR
- X-ray polarimetry of the accreting pulsar GX 301-2
- A polarimetrically oriented X-ray stare at the accreting pulsar EXO 2030+375
- Possible regular phenomena in EXO 2030+375
- Studying the accretion geometry of EXO 2030+375 at luminosities close to the propeller regime
- Analyzing X-Ray Pulsar Profiles: Geometry and Beam Pattern of EXO 2030+375
- Dynamical Effects of Magnetic Opacity in Neutron Star Accretion Columns
- Glancing through the accretion column of EXO 2030+375
- Timing analysis of EXO 2030+375 during its 2021 giant outburst observed with Insight-HXMT
- Common patterns in pulse profiles of High Mass X-ray Binaries
- Spectral & Timing analysis of Be/X-ray binary EXO 2030+375 during its giant 2021 outburst
- Phase resolved spectrum of the Crab pulsar from NICER
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