The physics of disk winds, jets, and X-ray variability in GRS 1915+105

AbstractWe present new insights about accretion and ejection physics based on joint RXTE/Chandra HETGS studies of rapid X-ray variability in GRS 1915+105. For the first time, with fast phase-resolved spectroscopy of the ρ state, we are able to show that changes in the broadband X-ray spectrum (RXTE) on timescales of seconds are associated with measurable changes in absorption lines (Chandra HETGS) from the accretion disk wind. Additionally, we make a direct detection of material evaporating from the radiation-pressure-dominated inner disk. Our X-ray data thus reveal the black hole as it ejects a portion of the inner accretion flow and then drives a wind from the outer disk, all in a bizarre cycle that lasts fewer than 60 seconds but can repeat for weeks. We find that the accretion disk wind may be sufficiently massive to play an active role in GRS 1915+105, not only in quenching the jet on long timescales, but also in possibly producing or facilitating transitions between classes of X-ray variability.

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Optical Short-Time Variations in GK Persei during the 1983 Outburst

International Astronomical Union Colloquium ◽

10.1017/s0252921100105251 ◽

1987 ◽

Vol 93 ◽

pp. 485-485

Author(s):

H. Steinle ◽

W. Pietsck

Keyword(s):

Accretion Disk ◽

Time Resolution ◽

X Rays ◽

X Ray ◽

Time Variations ◽

Short Time ◽

First Time ◽

Calar Alto

AbstractDuring the August 1983 outburst of the old nova GK Persei observations with EXOSAT showed for the first time a 351 second periodicity in X-rays.Our fast photometry (U(B)V with 25 sec time resolution) was made at the end of the outburst in the nights of September 29 , and October 1–3 , using the 2.2 meter telescope at Calar Alto (Spain).Optical variations up to 10% in U and 4% in V with periodicities in the range 350 to 360 seconds were found, lasting only for few cycles.A comparison with the extrapolated prediction of the X-ray maxima did not show a coincidence, but rather an anticoincidence in several cases. This supports a model of reprocessed X-rays at the inner edge of an accretion disk.

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The Nature of the Compact Object in the Hard X-Ray Source 4U2206+54

International Astronomical Union Colloquium ◽

10.1017/s0252921100152546 ◽

2004 ◽

Vol 194 ◽

pp. 208-208

Author(s):

J. M. Torrejón ◽

I. Kreykenbohni ◽

A. Orr ◽

L. Titarchuk ◽

I. Negueruela

Keyword(s):

Neutron Star ◽

Accretion Disk ◽

Compact Object ◽

High Energy ◽

Energy Data ◽

X Ray ◽

Hot Plasma ◽

Cyclotron Line ◽

First Time

We present an analysis of archival RXTE and BeppoSAX data of the X-ray source 4U2206+54. For the first time, high energy data (≥ 30 keV) is analyzed. The data is well described by comptonization models in which seed photons with temperatures between 1.1 keV arid 1.5 keV are comptonized by a hot plasma at 50 keV thereby producing a hard tail which extends up to 100 keV. From luminosity arguments it is shown that the area of the soft photons source must be small (r ≈ 1 km) and that the presence of an accretion disk in this system is unlikely. Here we report on the possible existence of a cyclotron line around 30 keV . The presence of a neutron star in the system is strongly favored by the available data.

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A New Chapter in Hard X-rays of the M87 AGN

Proceedings ◽

10.3390/proceedings2019017009 ◽

2019 ◽

Vol 17 (1) ◽

pp. 9

Author(s):

Ka-Wah Wong ◽

Rodrigo S. Nemmen ◽

Jimmy A. Irwin ◽

Dacheng Lin

Keyword(s):

High Energy ◽

X Rays ◽

X Ray ◽

Accretion Flow ◽

Relativistic Jet ◽

Very High Energy ◽

Γ Ray ◽

High Energy Emission ◽

First Time ◽

Very High

The nearby M87 hosts an exceptional relativistic jet. It has been regularly monitored in radio to TeV bands, but little has been done in hard X-rays ≳10 keV. For the first time, we have successfully detected hard X-rays up to 40 keV from its X-ray core with joint Chandra and NuSTAR observations, providing important insights to the X-ray origins: from the unresolved jet or the accretion flow. We found that the hard X-ray emission is significantly lower than that predicted by synchrotron self-Compton models introduced to explain very-high-energy γ -ray emission above a GeV. We discuss recent models to understand these high energy emission processes.

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GRS 1915+105 IN “SOFT STATE”: NATURE OF ACCRETION DISK WIND AND ORIGIN OF X-RAY EMISSION

The Astrophysical Journal ◽

10.1088/0004-637x/695/2/888 ◽

2009 ◽

Vol 695 (2) ◽

pp. 888-899 ◽

Cited By ~ 81

Author(s):

Yoshihiro Ueda ◽

Kazutaka Yamaoka ◽

Ronald Remillard

Keyword(s):

Accretion Disk ◽

X Ray ◽

Disk Wind ◽

Soft State ◽

State Nature

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An Archival Study of HST Observations of Her X-1/HZ Her

International Astronomical Union Colloquium ◽

10.1017/s0252921100039208 ◽

1996 ◽

Vol 158 ◽

pp. 381-382

Author(s):

F. H. Cheng ◽

S. D. Vrtilek ◽

J. C. Raymond

Keyword(s):

Accretion Disk ◽

Model Fitting ◽

Rotation Period ◽

Emission Lines ◽

High Quality ◽

Detailed Model ◽

Companion Star ◽

X Ray ◽

First Time ◽

Archival Study

Her X-1 is an X-ray pulsar with a rotation period of 1.24 s and a binary period of 1.7d (Tananbaum et al. 1972). The 1.7 d variations in optical and ultraviolet flux are attributed to X-ray heating of the companion star and disk (e.g. Howarth & Wilson 1983, hereafter HW83). The system displays a 35 d period, attributed to the effects of a tilted, precessing, accretion disk. Optical and ultraviolet flux variations continue unchanged throughout. This work is motivated by the following reasons:• The observed IUE spectra have significantly flatter slopes than those predicted by previous models (e.g. HW83).• The observed strength of the Balmer jump is anomalously low compared to that expected for a normal B star (Anderson et al. 1994).• HST observations obtained by Anderson et al. (1994) in order to study emission lines have yielded high quality spectra of the continuum emission from HZ Her, enabling for the first time detailed model fitting efforts.

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The Accretion Disk Model for the First Hundred Days of the Outburst Evolution in the Black Hole X-Ray Novae

International Astronomical Union Colloquium ◽

10.1017/s0252921100038471 ◽

1996 ◽

Vol 158 ◽

pp. 139-140

Author(s):

S.-W. Kim ◽

J. C. Wheeler ◽

S. Mineshige

Keyword(s):

Mass Transfer ◽

Black Hole ◽

Accretion Disk ◽

Mass Transfer Rate ◽

Time Dependent ◽

Disk Model ◽

X Ray ◽

Outer Disk ◽

Appreciable Increase ◽

Shadowing Effect

We present time-dependent, irradiated, accretion disk models for the black hole X-ray novae in the first hundred days of the dwarf nova-like outbursts, including the rise, precursor, maximum and the secondary re-flare. This work is based on the disk instability model (Kim, Mineshige & Wheeler 1996, Kim, Wheeler & Mineshige 1996). The model is reasonably consistent with the observed optical light curves. The irradiators are the central hot region around the black hole, and the corona or chromosphere above the accretion disk. In addition, we include the time-dependent shadowing effect and consequent blocking of the outer portions of the disk from the central irradiator. We find the stagnation phenomenon whereby the disk stays in the intermediate temperature stage between the hot and cool state. This can explain the recently discovered optical precursor rise prior to the maximum light in Nova Sco 1994 (Bailyn et al. 1995: see Fig. 1). We suggest the secondary re-flare after the maximum is due to the coupled effects of the irradiation and stagnation. In the model, the stagnation phenomenon during the rise results from the partial ionization and molecular opacity. In addition, we find irradiation-induced stagnation during the decay phase, which is consistent with the observed secondary re-flare in X-ray novae (see Fig. 1). In the overall evolution of model outbursts in the first hundred days, the outer disk is blocked from the irradiation and, in turn, the companion star may not be strongly irradiated. This suggests that there is no appreciable increase of mass transfer rate during the decay prior to the secondary re-flare, unlike the behaviour in the mass transfer burst models.

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X-ray radiation of the jets and the supercritical accretion disk in SS 433

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310016169 ◽

2010 ◽

Vol 6 (S275) ◽

pp. 280-284 ◽

Cited By ~ 1

Author(s):

Sergei Fabrika ◽

Alexei Medvedev

Keyword(s):

Accretion Disk ◽

Spectral Component ◽

Emission Lines ◽

X Rays ◽

X Ray ◽

Ss 433 ◽

Disk Wind ◽

Bolometric Luminosity ◽

Supercritical Accretion ◽

The Continuum

AbstractThe observed X-ray luminosity of SS 433 is ~1036 erg/s, it is known that all the radiation is formed in the famous SS 433 jets. The bolometric luminosity of SS 433 is ~1040 erg/s, and originally the luminosity must be realized in X-rays. The original radiation is probably thermalized in the supercritical accretion disk wind, however the missing more than four orders of magnitude is surprising. We have analysed the XMM-Newton spectra of SS 433 using a model of adiabatically and radiatively cooling X-ray jets. The multi-temperature thermal jet model reproduces very well the strongest observed emission lines, but it can not reproduce the continuum radiation and some spectral features. We have found a notable contribution of ionized reflection to the spectrum in the energy range from ~3 to 12 keV. The reflected spectrum is an evidence of the supercritical disk funnel, where the illuminating radiation comes from deeper funnel regions, to be further reflected in the outer visible funnel walls (r ≥ 2 ⋅ 1011 cm). The illuminating spectrum is similar to that observed in ULXs, its luminosity has to be no less than ~1039 erg/s. A soft excess has been detected, that does not depend on the thermal jet model details. It may be represented as a BB with a temperature of Tbb ≈ 0.1 keV and luminosity of Lbb~3 ⋅ 1037 erg/s. The soft spectral component has about the same parameters as those found in ULXs.

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The supercritical accretion disk in SS 433 and ultraluminous X-ray sources

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307005017 ◽

2006 ◽

Vol 2 (S238) ◽

pp. 225-228

Author(s):

S. N. Fabrika ◽

P. K. Abolmasov ◽

S. Karpov

Keyword(s):

Accretion Disk ◽

Accretion Disks ◽

X Rays ◽

X Ray ◽

Ss 433 ◽

Disk Wind ◽

Flux Variability ◽

Typical Time ◽

Supercritical Accretion ◽

External Galaxies

AbstractSS 433 is the only known persistent supercritical accretor, it may be very important for understanding ultraluminous X-ray sources (ULXs) located in external galaxies. We describe main properties of the SS 433 supercritical accretion disk and jets. Basing on observational data of SS 433 and published 2D simulations of supercritical accretion disks we estimate parameters of the funnel in the disk/wind of SS 433. We argue that the UV radiation of the SS 433 disk (∼ 50000 K, ∼ 1040erg/s) is roughly isotropic, but X-ray radiation (∼ 107K, ∼ 1040erg/s) of the funnel is mildly anisotropic. A face-on SS 433 object has to be ultraluminous in X-rays (1040–41erg/s). Typical time-scales of the funnel flux variability are estimated. Shallow and very broad (0.1-0.3c) and blue-shifted absorption lines are expected in the funnel X-ray spectrum.

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