Extending the baseline for SMC X-1's spin and orbital behavior with NuSTAR stray light

Abstract

StrayCats, the catalog of NuSTAR stray light observations, contains data from bright X-ray sources that fall within crowded source regions. These observations offer unique additional data with which to monitor sources like X-ray binaries that show variable timing behavior. In this work, we present a timing analysis of stray light data of the high mass X-ray binary SMC X-1, the first scientific analysis of a single source from the StrayCats project. We describe the process of screening stray light data for scientific analysis, verify the orbital ephemeris, and create both time and energy resolved pulse profiles. We find that the orbital ephemeris of SMC X-1 is unchanged and confirm a long-term spin up rate of $\dot{\nu }=(2.52\pm 0.03)\times 10^{-11}$ Hz s${}^{-1}$. We also note that the shape of SMC X-1's pulse profile, while remaining double-peaked, varies significantly with time and only slightly with energy.

arXiv comment10 pages, 8 figures

References in corpus (21)

• The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission
• The MAXI Mission on the ISS: Science and Instruments for Monitoring All Sky X-Ray Images
• ISGRI: the INTEGRAL Soft Gamma-Ray Imager
• Stingray: A Modern Python Library For Spectral Timing
• Precessing warped accretion discs in X-ray binaries
• The ephemeris, orbital decay, and masses of 10 eclipsing HMXBs
• Determination of the mass of the neutron star in SMC X-1, LMC X-4 and Cen X-3 with VLT/UVES
• Quasi-Periodic Occultation by a Precessing Accretion Disk and Other Variabilities of SMC X-1
• Long-term Properties of Accretion Disks in X-ray Binaries: I. the variable third period in SMC X-1
• Effect of pulse profile variations on measurement of eccentricity in orbits of Cen X-3 and SMC X-1
• Pulse-phase spectroscopy of SMC X-1 with Chandra and XMM-Newton: reprocessing by a precessing disk?
• Phase Variation in the Pulse Profile of SMC X-1
• Modeling the precession of the warped inner accretion disk in the pulsars LMC X-4 and SMC X-1 with NuSTAR and XMM-Newton
• Extending the $Z_n^2$ and $H$ statistics to generic pulsed profiles
• Analysis of RXTE-PCA Observations of SMC X-1
• Observing the transient pulsations of SMC X-1 with NuSTAR
• StrayCats: A catalog of NuSTAR Stray Light Observations
• Is superorbital modulation in SMC X-1 caused by absorption in warped precessing accretion disc?
• Longterm properties of accretion discs in X-ray Binaries - III. A search for spin-superorbital correlation in SMC X-1
• Monitoring the Superorbital Period Variation and the Spin Period Evolution of SMC X-1
• Superorbital Phase-Resolved Analysis of SMC X-1

Cited by in corpus (7)

• Geminga's pulsar halo: an X-ray view
• The Orbit of NGC 5907 ULX-1
• StrayCats II: An Updated Catalog of NuSTAR Stray Light Observations
• Monitoring observations of SMC X-1's excursions (MOOSE)-II: A new excursion accompanies spin-up acceleration
• Constraining the evolution of the unstable accretion disk in SMC X-1 with NICER
• NuSTAR spectral analysis beyond 79 keV with stray light
• Wavelet-based image decomposition method for NuSTAR stray light background studies