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Related papers: Links Between Z Sources and Atoll Sources

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Twin peak quasi-periodic oscillations (QPOs) appear in the X-ray power-density spectra of several accreting low-mass neutron star (NS) binaries. Observations of the peculiar Z-source Circinus X-1 display unusually low QPO frequencies. Using…

High Energy Astrophysical Phenomena · Physics 2014-08-20 Gabriel Torok , Pavel Bakala , Eva Sramkova , Zdenek Stuchlik , Martin Urbanec , Katerina Goluchova

We consider the interpretation of a pair of kHz Quasi Periodic Oscillations (QPOs) in the Fourier spectra of two Low Mass X-Ray Binaries, Sco X-1 and 4U1608-52, hosting an old accreting neutron star. The observed frequency difference of…

Astrophysics · Physics 2008-11-26 Luigi Stella , Mario Vietri

In this paper we investigate the properties of low X-ray-to-optical flux ratio sources detected in a wide area (2.5deg^2) shallow (f(0.5-8keV)~10e-14cgs) XMM-Newton survey. We find a total of 26 sources (5% of the total X-ray selected…

We continue exploring our understanding of the collective properties of X-ray binaries in the stellar fields (i.e., outside globular clusters) of normal galaxies, introduced in Paper I of this series, where we considered high-mass X-ray…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Harshal Bhadkamkar , Pranab Ghosh

Double peak kHz QPO frequencies in neutron star sources varies in time by a factor of hundreds Hz while in microquasar sources the frequencies are fixed and located at the line \nu_2 = 1.5 \nu_1 in the frequency-frequency plot. The crucial…

Astrophysics · Physics 2007-05-23 M. A. Abramowicz , D. Barret , M. Bursa , J. Horak , W. Kluzniak , P. Rebusco , G. Torok

In this chapter we give an overview of the properties of X-ray binary systems containing a weakly magnetized neutron star. These are old (Giga-years life-time) semi-detached binary systems containing a neutron star with a relatively weak…

High Energy Astrophysical Phenomena · Physics 2023-11-22 Tiziana Di Salvo , Alessandro Papitto , Alessio Marino , Rosario Iaria , Luciano Burderi

The origin of quasi periodic modulations of flux in the kilohertz range (kHz QPOs), observed in low-mass X-ray binaries, is usually assumed to be physically distinct from that of the ``normal branch oscillations'' (NBOs) in the Z-sources.…

Astrophysics · Physics 2015-06-24 J. Horak , M. Abramowicz , V. Karas , W. Kluzniak

Recent hard X-ray surveys have proven to be effective in discovering large numbers of X-ray sources that, despite the likely association with active nuclei, appear to be characterized by "peculiar" properties. Among these "exotic" source…

Astrophysics · Physics 2007-05-23 C. Vignali , M. Mignoli

Recent work on jets and disk winds in low-mass X-ray binaries (LMXBs) suggests that they are to a large extent mutually exclusive, with jets observed in spectrally hard states and disk winds observed in spectrally soft states. In this paper…

We report on the results of NuSTAR and XMM-Newton observations of the persistent X-ray source 1E1743.1-2843, located in the Galactic Center region. The source was observed between September and October 2012 by NuSTAR and XMM-Newton,…

Kilohertz quasi-periodic oscillations (kHz QPOs) has been regarded as representing the Keplerian frequency at the inner disk edge in the neutron star X-ray binaries. The so-called ``parallel tracks'' on the plot of the kHz QPO frequency vs.…

Astrophysics · Physics 2007-05-23 Wenfei Yu

Based on the results of applying the extended ADC emission model for low mass X-ray binaries to three Z-track sources: GX340+0, GX5-1 and CygX-2, we propose an explanation of the CygnusX-2 like Z-track sources. The Normal Branch is…

High Energy Astrophysical Phenomena · Physics 2015-05-14 M. Balucinska-Church , A. Gibiec , N. K. Jackson , M. J. Church

X-ray timing of neutron stars in low-mass X-ray binaries (LMXBs) with RXTE has since 1996 revealed several distinct high-frequency phenomena. Among these are oscillations during thermonuclear (type-I) bursts, which (in addition to…

Astrophysics · Physics 2009-06-23 Duncan Galloway

The dramatic discovery with the Rossi X-Ray Timing Explorer satellite of remarkably coherent $\sim$300--1200 Hz oscillations in the X-ray brightness of some sixteen neutron stars in low-mass binary systems has spurred theoretical modeling…

Astrophysics · Physics 2009-10-30 Frederick K. Lamb , M. Coleman Miller , Dimitrios Psaltis

Ultra-luminous X-ray sources (ULXs) are off-nuclear point sources in nearby galaxies with luminosities well exceeding the Eddington limit for stellar-mass objects. It has been recognized after the discovery of pulsating ULXs (PULXs) that a…

High Energy Astrophysical Phenomena · Physics 2020-01-22 M. Hakan Erkut , K. Yavuz Ekşi

In numerous low-mass X-ray binaries kHz quasi-periodic oscillations (kHz QPOs) are detected. We observed the atoll sources GX 9+1 and GX 9+9 with the RXTE satellite. Both sources were on the (upper) banana branch during our observations. No…

Astrophysics · Physics 2007-05-23 Rudy Wijnands , Michiel van der Klis , Jan van Paradijs

In the last 20 years our understanding of the millisecond pulsar (MSP) population changed dramatically. Thanks to RXTE, we discovered that neutron stars in LMXBs spins at 200-750 Hz frequencies, and indirectly confirmed the recycling…

High Energy Astrophysical Phenomena · Physics 2019-03-06 Sergio Campana , Tiziana Di Salvo

Ultraluminous X-ray sources (ULXs) are likely to include different physical types of objects. We discuss some possible subclasses, reviewing the properties of a sample of ULXs recently observed by Chandra and XMM-Newton. Sources with an…

Astrophysics · Physics 2007-05-23 Roberto Soria , Mark Cropper , Christian Motch

X-ray bursts from bright sources in globular clusters of our galaxy show that at least 11 (of a total 13) of these sources are neutron stars. One of the low-luminosity X-ray sources in omega Cen is a neutron star accreting at a low rate.…

Astrophysics · Physics 2007-05-23 Frank Verbunt

We report the first polarimetric results of the neutron star (NS) low-mass X-ray binary (LMXB) Z-source GX 17+2 using the Imaging X-ray Polarimetry Explorer (IXPE) and the Very Large Array (VLA). We find that the X-ray source was polarized…

High Energy Astrophysical Phenomena · Physics 2025-10-08 Unnati Kashyap , Thomas J. Maccarone , Eliot C. Pattie , Mason Ng , Swati Ravi , Alexandra J. Tetarenko , Pau Bosch Cabot , Herman L. Marshall
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