Continuous monitoring of pulse period variations in Her X-1 using Swift/BAT

@article{Klochkov2009ContinuousMO,
  title={Continuous monitoring of pulse period variations in Her X-1 using Swift/BAT},
  author={Dmitry Klochkov and Ruediger Staubert and Konstantin A Postnov and Nikolai I. Shakura and A. Santangelo},
  journal={arXiv: High Energy Astrophysical Phenomena},
  year={2009}
}
Context: Monitoring of pulse period variations in accreting binary pulsars is an important tool to study the interaction between the magnetosphere of the neutron star and the accretion disk. While the X-ray flux of the brightest X-ray pulsars have been successfully monitored over many years (e.g. with RXTE/ASM, CGRO/BATSE, Swift/BAT), the possibility to monitor their pulse timing properties continuously has so far been very limited. Aims: In our work we show that the Swift/BAT observations can… Expand

Figures from this paper

Variable pulse profiles of Hercules X-1 repeating with the same irregular 35 d clock as the turn-ons
The accreting X-ray pulsar Her X-1 shows two types of long-term variations, both with periods of ∼35 days: 1) turn-on cycles, a modulation of the flux, with a ten-day long main-on and a five-day longExpand
Is there a highly magnetized neutron star in GX 301–2?
We present the results of an in-depth study of the long-period X-ray pulsar GX 301−2. Using archival data of INTEGRAL, RXTE ASM ,a ndCGRO BATSE, we study the spectral and timing properties of theExpand
Hercules X-1: Using Eclipse to Measure the X-Ray Corona
Observations of HZ Her/Her X-1 by the Rossi X-ray Timing Explorer during High State X-ray eclipses are analyzed. After a sharp ingress caused by the neutron star receding behind the companion star HZExpand
HZ Her: Stellar Radius from X-ray Eclipse Observations, Evolutionary State and a New Distance
Observations of HZ Her/Her X-1 by the Rossi X-ray Timing Explorer (RXTE) covering high state eclipses of the neutron star are analyzed here. Models of the eclipse are used to measure the radius andExpand
Application of the Ghosh & Lamb relation to the spin-up/down behavior in the X-ray binary pulsar 4U 1626−67
We analyzed continuous MAXI/GSC data of the X-ray binary pulsar 4U 1626-67 from 2009 October to 2013 September, and determined the pulse period and the pulse-period derivative for every 60-d intervalExpand
Anti-glitches in the Ultraluminous Accreting Pulsar NGC 300 ULX-1 Observed with NICER
We report the discovery of three spin-down glitches (or `anti-glitches') in the ultraluminous accreting X-ray pulsar NGC 300 ULX-1 in timing observations made with the Neutron Star InteriorExpand
Properties and observability of glitches and anti-glitches in accreting pulsars
Several glitches have been observed in young, isolated radio pulsars, while a clear detection in accretion-powered X-ray pulsars is still lacking. We use the Pizzochero snowplow model for pulsarExpand
AstroSat SXT Observations of Her X-1
Two observations of the X-ray binary system Her X-1 by the AstroSat Soft X-ray Telescope were carried out in 2017. The first was during Low State and Turn-On, the second was during Main High StateExpand
RXTE-based 35 Day Cycle Turn-on Times for Hercules X-1
The 35 day X-ray cycle of Hercules X-1 (Her X-1) has been the subject of intense study since its discovery over 30 years ago. This work summarizes the results of determination of 35 day cycle turn-onExpand
A diagnosis of torque reversals in 4U 1626-67
Several X-ray pulsars have been observed to experience torque reversals, which provide important observational clues to the interaction between the neutron star magnetic field and the accretion disk.Expand
...
1
2
...

References

SHOWING 1-10 OF 32 REFERENCES
Discovery of a periodic pulsating binary X-ray source in Hercules from Uhuru.
We have discovered a new pulsating X-ray source with a 1.24-sec period in the constellation Hercules. Analysis of 5 months of data has shown the existence of periodic variations in the intensity ofExpand
INTEGRAL observations of Hercules X-1
Aims. We investigate the X-ray spectral and timing properties of the accreting X-ray pulsar Her X-1 observed with the INTEGRAL satellite in July–August 2005. Methods. The data analyzed in this workExpand
Discovery of a flux-related change of the cyclotron line energy in Hercules X-1
Aims. We present the results of ten years of repeated measurements of the Cyclotron Resonance Scattering Feature (CRSF) in the spectrum of the binary X-ray pulsar Her X-1 and report the discovery ofExpand
Decrease in the orbital period of Hercules X-1
From a pulse-timing analysis of Ginga observations of the binary X-ray pulsar Her X-1 obtained during the interval 1989 April-June we have determined local orbital parameters for a Short High state.Expand
The Swift gamma-ray burst mission
TLDR
The Swift mission will determine the origin of GRB, classify GRBs and search for new types, study the interaction of the ultrarelativistic outflows of GRBs with their surrounding medium, and use GRBs to study the early universe out to z >10. Expand
Hot Outflowing Gas from the X-Ray Binary Hercules X-1
We present a unified picture of outflowing gas from the X-ray binary system Hercules X-1/HZ Herculis. We suggest that the outflowing gas (a wind) causes UV emission seen in mid-eclipse, narrow UVExpand
Evidence for strong cyclotron line emission in the hard X-ray spectrum of Hercules X-1
We present further results of our Hercules X-1 balloon observation on 1976 May 3 which confirm the existence of a strong line feature at approx.58 keV in the pulsed (1.24s) X-ray spectrum we reportedExpand
Multiwavelength Studies of Hercules X-1 during Short High and Anomalous Low States: On-again, Off-again
We present results from multiwavelength observations of the Hercules X-1 system during a short high state (SHS) and during an anomalous low state (ALS). The magnitude of deviation from spin-upExpand
Periodic mass transfer in Hercules X-1/HZ Herculis
Various features in the X-ray light curve of Her X-1, primarily pre-eclipse and anomalous dips, 0.3 and 0.7 orbital phase turn-ons, are all seen to be aspects of only a single process of periodicExpand
Two ~35 day clocks in Hercules X-1: evidence for neutron star free precession
We present evidence for the existence of two ∼35 day clocks in the Her X-1/HZ Her binary system. ∼35 day modulations are observed 1) in the Turn-On cycles with two on- and two off-states and 2) inExpand
...
1
2
3
4
...