TV Cassiopeiae with Chandra and XMM–Newton X-ray Observations

TV Cassiopeia (TV Cas) is a well-known eclipsing Algol-type binary comprising a B9V primary and F7 IV secondary in an orbit with a period of 1.81 days, together with a purported low-mass companion in a wide orbit. Despite the considerable attention TV Cas has received in optical and UV bands, no X-ray analysis has been reported. Chandra has detected TV Cas six times and XMM–Newton observed it twice, all serendipitously during observations of the starburst galaxy IC 10. We have put all the X-ray data together to investigate its coronal morphology and spectral properties. We use the X-ray light curves and eclipses to probe the emitting geometry and the X-ray spectra at different epochs to investigate the activity mechanisms and test speculation that TV Cas undergoes significant mass transfer episodes.

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The study of multipeaked type-I X-ray bursts in the neutron star low-mass X-ray binary 4U 1636 − 536 with RXTE

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3539 ◽

2020 ◽

Vol 501 (1) ◽

pp. 168-178

Author(s):

Chen Li ◽

Guobao Zhang ◽

Mariano Méndez ◽

Jiancheng Wang ◽

Ming Lyu

Keyword(s):

Neutron Star ◽

Flux Ratio ◽

Light Curves ◽

Type I ◽

X Ray ◽

Soft State ◽

Peak Flux ◽

Low Mass ◽

Two Peaks ◽

Second Peak

ABSTRACT We have found and analysed 16 multipeaked type-I bursts from the neutron-star low-mass X-ray binary 4U 1636 − 53 with the Rossi X-ray Timing Explorer (RXTE). One of the bursts is a rare quadruple-peaked burst that was not previously reported. All 16 bursts show a multipeaked structure not only in the X-ray light curves but also in the bolometric light curves. Most of the multipeaked bursts appear in observations during the transition from the hard to the soft state in the colour–colour diagram. We find an anticorrelation between the second peak flux and the separation time between two peaks. We also find that in the double-peaked bursts the peak-flux ratio and the temperature of the thermal component in the pre-burst spectra are correlated. This indicates that the double-peaked structure in the light curve of the bursts may be affected by enhanced accretion rate in the disc, or increased temperature of the neutron star.

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Constraining Progenitors of Observed Low-mass X-ray Binaries Using Convection and Rotation-Boosted Magnetic Braking

The Astrophysical Journal ◽

10.3847/1538-4357/ac236c ◽

2021 ◽

Vol 922 (2) ◽

pp. 174

Author(s):

Kenny X. Van ◽

Natalia Ivanova

Keyword(s):

Mass Transfer ◽

Binary Systems ◽

Formation Rate ◽

Mass Transfer Rate ◽

Population Synthesis ◽

X Ray ◽

Synthesis Technique ◽

Low Mass ◽

Magnetic Braking ◽

X Ray Binaries

Abstract We present a new method for constraining the mass transfer evolution of low-mass X-ray binaries (LMXBs)—a reverse population synthesis technique. This is done using the detailed 1D stellar evolution code MESA (Modules for Experiments in Stellar Astrophysics) to evolve a high-resolution grid of binary systems spanning a comprehensive range of initial donor masses and orbital periods. We use the recently developed convection and rotation-boosted (CARB) magnetic braking scheme. The CARB magnetic braking scheme is the only magnetic braking prescription capable of reproducing an entire sample of well-studied persistent LMXBs—those with mass ratios, periods, and mass transfer rates that have been observationally determined. Using the reverse population synthesis technique, where we follow any simulated system that successfully reproduces an observed LMXB backward, we have constrained possible progenitors for each observed well-studied persistent LMXB. We also determined that the minimum number of LMXB formations in the Milky Way is 1500 per Gyr if we exclude Cyg X-2. For Cyg X-2, the most likely formation rate is 9000 LMXB Gyr−1. The technique we describe can be applied to any observed LMXB with well-constrained mass ratio, period, and mass transfer rate. With the upcoming GAIA DR3 containing information on binary systems, this technique can be applied to the data release to search for progenitors of observed persistent LMXBs.

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Swift/XRT, Chandra, and XMM–Newton observations of IGR J17091–3624 as it returns into quiescence

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2009 ◽

2020 ◽

Vol 497 (1) ◽

pp. 1115-1126

Author(s):

M Pereyra ◽

D Altamirano ◽

J M C Court ◽

N Degenaar ◽

R Wijnands ◽

...

Keyword(s):

Black Hole ◽

Neutron Star ◽

Time Scales ◽

Strong Evidence ◽

Spectral Properties ◽

X Ray ◽

Term Evolution ◽

Wide Range ◽

Low Mass

ABSTRACT IGR J17091–3624 is a low-mass X-ray binary (LMXB), which received wide attention from the community thanks to its similarities with the bright black hole system GRS 1915+105. Both systems exhibit a wide range of highly structured X-ray variability during outburst, with time-scales from few seconds to tens of minutes, which make them unique in the study of mass accretion in LMXBs. In this work, we present a general overview into the long-term evolution of IGR J17091–3624, using Swift/XRT observations from the onset of the 2011–2013 outburst in 2011 February till the end of the last bright outburst in 2016 November. We found four re-flares during the decay of the 2011 outburst, but no similar re-flares appear to be present in the latter one. We studied, in detail, the period with the lowest flux observed in the last 10 yr, just at the tail end of the 2011–2013 outburst, using Chandra and XMM-Newton observations. We observed changes in flux as high as a factor of 10 during this period of relative quiescence, without strong evidence of softening in the spectra. This result suggests that the source has not been observed at its true quiescence so far. By comparing the spectral properties at low luminosities of IGR J17091–3624 and those observed for a well-studied population of LMXBs, we concluded that IGR J17091–3624 is most likely to host a black hole as a compact companion rather than a neutron star.

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Super-Eddington Accretion in the Formation of Low-Mass X-ray Binaries and Millisecond Pulsars

International Astronomical Union Colloquium ◽

10.1017/s0252921100044213 ◽

1997 ◽

Vol 163 ◽

pp. 828-829 ◽

Cited By ~ 3

Author(s):

R. F. Webbink ◽

V. Kalogera

Keyword(s):

Mass Transfer ◽

Initial Phase ◽

Transfer Rate ◽

Birth Rate ◽

Mass Transfer Rate ◽

Millisecond Pulsars ◽

X Ray ◽

Low Mass ◽

Orbital Periods ◽

X Ray Binaries

AbstractConsiderations of donor star stability, age, and mass transfer rate show that low-mass X-ray binaries and binary millisecond pulsars with orbital periods longer than a few days must have survived an initial phase of super-Eddington mass transfer. We review the physical arguments leading to this conclusion, and examine its implications for the apparent discrepancy between the death rate for low-mass X-ray binaries and the birth rate of binary millisecond pulsars.

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Understanding X-ray irradiation in low-mass X-ray binaries directly from their light-curves

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/sty1798 ◽

2018 ◽

Vol 480 (1) ◽

pp. 2-16 ◽

Cited By ~ 11

Author(s):

BE Tetarenko ◽

G Dubus ◽

J-P Lasota ◽

CO Heinke ◽

GR Sivakoff

Keyword(s):

Light Curves ◽

X Ray ◽

Low Mass ◽

X Ray Binaries

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Non-Linear Resonances in Accretion Disks and QPOs

International Astronomical Union Colloquium ◽

10.1017/s0252921100152170 ◽

2004 ◽

Vol 194 ◽

pp. 128-129

Author(s):

Włodek Kluźniak

Keyword(s):

Black Holes ◽

Neutron Stars ◽

Accretion Disk ◽

Accretion Disks ◽

High Frequency ◽

Light Curves ◽

X Ray ◽

Non Linear ◽

Low Mass ◽

X Ray Binaries

AbstractNon-linear oscillations in the accretion disk are favored as an explanation of high-frequency QPOs observed in the light curves of low-mass X-ray binaries containing neutron stars, black holes, or white dwarfs.

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Optical Photometry of LMXBs: UW CrB (=MS 1603+260) and V1408 Aql (=4U 1957+115)

Acta Polytechnica CTU Proceedings ◽

10.14311/app.2015.02.0050 ◽

2015 ◽

Vol 2 (1) ◽

pp. 50-54

Author(s):

P. A. Mason ◽

E. L. Robinson ◽

S. Gomez ◽

J. V. Segura

Keyword(s):

Black Hole ◽

Orbital Period ◽

Light Curves ◽

Optical Data ◽

Published Data ◽

Type I ◽

Optical Photometry ◽

Mean Intensity ◽

X Ray ◽

Low Mass

We present new optical observations of V1408 Aql (= 4U 1957+115), the only low mass X-ray binary, black hole candidate known to be in a persistently soft state. We combine new broadband optical photometry with previously published data and derive a precise orbital ephemeris. The optical light curves display sinusoidal variations modulated on the orbital period as well as large night to night changes in mean intensity. The amplitude of the variations increases with mean intensity while maintaining sinusoidal shape. Considering the set of constraints placed by the X-ray and optical data we argue that V1408 Aql may harbor a very low mass black hole. Optical light curves of UW CrB display partial eclipses of the accretion disk by the donor star that vary both in depth and orbital phase. The new eclipses of UW CrB in conjunction with published eclipse timings are well fitted with a linear ephemeris. We derive an upper limit to the rate of change of the orbital period. By including the newly observed type I bursts with published bursts in our analysis, we find that optical bursts are not observed between orbital phases 0.93 and 0.07, i.e. they are not observable during partial eclipses of the disk.

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R-modes in neutron stars: Theory and observations

International Journal of Modern Physics E ◽

10.1142/s0218301315410074 ◽

2015 ◽

Vol 24 (09) ◽

pp. 1541007 ◽

Cited By ~ 37

Author(s):

B. Haskell

Keyword(s):

Neutron Stars ◽

Light Curves ◽

Mutual Friction ◽

Mode Instability ◽

Flux Tubes ◽

X Ray ◽

Physical Mechanisms ◽

Low Mass ◽

Superfluid Vortices ◽

X Ray Binaries

In this paper, I will review the theory behind the gravitational wave (GW) driven r-mode instability in rapidly rotating neutron stars (NSs) and discuss which constraints can be derived from observations of spins and temperatures in low mass X-ray binaries (LMXBs). I will discuss how a standard, 'minimal' NS model is not consistent with the data, and discuss some of the additional physical mechanisms that could reconcile theory with observations. In particular, I will focus on additional forms of damping due to exotic cores and on strong mutual friction due to superfluid vortices cutting through superconducting flux tubes, and examine the repercussions these effects could have on the saturation amplitude of the mode. Finally I will also discuss the possibility that oscillations due to r-modes may have been recently observed in the X-ray light curves of two LMXBs.

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