X-Ray Evidence Against the Hypothesis that the Hyperluminous z = 6.3 Quasar J0100+2802 is Lensed

Abstract The z = 6.327 quasar SDSS J010013.02+280225.8 (hereafter J0100+2802) is believed to be powered by a black hole more massive than 1010 M ⊙, making it the most massive black hole known in the first billion years of the universe. However, recent high-resolution ALMA imaging shows four structures at the location of this quasar, potentially implying that it is lensed with a magnification of μ ∼ 450 and thus its black hole is significantly less massive. Furthermore, for the underlying distribution of magnifications of z ≳ 6 quasars to produce such an extreme value, theoretical models predict that a larger number of quasars in this epoch should be lensed, implying further overestimates of early black hole masses. To provide an independent constraint on the possibility that J0100+2802 is lensed, we reanalyzed archival XMM-Newton observations of the quasar and compared the expected ratios of X-ray luminosity to rest-frame UV and IR luminosities. For both cases, J0100+2802's X-ray flux is consistent with the no-lensing scenario; while this could be explained by J0100+2802 being X-ray faint, we find it does not have the X-ray or optical spectral features expected for an X-ray faint quasar. Finally, we compare the overall distribution of X-ray fluxes for known, typical z ≳ 6 quasars. We find a 3σ tension between the observed and predicted X-ray-to-UV flux ratios when adopting the magnification probability distribution required to produce a μ = 450 quasar.

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Reprocessing of Uv and Line Emission in AGN Accretion Discs

Symposium - International Astronomical Union ◽

10.1017/s007418090017665x ◽

1994 ◽

Vol 159 ◽

pp. 489-489

Author(s):

Evlabia Rokaki ◽

Catherine Boisson

Keyword(s):

Black Hole ◽

Accretion Rate ◽

Line Emission ◽

Line Spectrum ◽

Physical Parameters ◽

Spectral Features ◽

Physical Processes ◽

Massive Black Hole ◽

X Ray ◽

The Continuum

It is commonly admitted that AGN contain a massive black hole fuelled most likely by an accretion disc. Several spectral features of the AGN, as the continuum excess in the UV and the broad line spectrum, involving different physical processes of emission (thermal for the UV continuum, photoionisation for the line spectrum) have been proposed as signatures of the disc. Physical parameters of the nucleus (as the mass of the black hole, M, the disc inclination, i, and accretion rate, Ṁ) are better determined when these two spectral features are modelled simultaneously. Here, we present results from the disc modelling (see) of the UV and broad Hβ emission of the 22 Seyfert 1 galaxies in a complete AGN sample selected in a hard X-ray survey.

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The Voyage of Metals in the Universe from Cosmological to Planetary Scales: the need for a Very High-Resolution, High Throughput Soft X-ray Spectrometer

Experimental Astronomy ◽

10.1007/s10686-021-09710-2 ◽

2021 ◽

Author(s):

F. Nicastro ◽

J. Kaastra ◽

C. Argiroffi ◽

E. Behar ◽

S. Bianchi ◽

...

Keyword(s):

Chemical Composition ◽

High Resolution ◽

Deep Understanding ◽

High Resolution Spectroscopy ◽

X Ray ◽

Viable Solution ◽

Surrounding Space ◽

Nuclear Processes ◽

The Universe ◽

Very High

AbstractMetals form an essential part of the Universe at all scales. Without metals we would not exist, and the Universe would look completely different. Metals are primarily produced via nuclear processes in stars, and spread out through winds or explosions, which pollute the surrounding space. The wanderings of metals in-and-out of astronomical objects are crucial in determining their own evolution and thus that of the Universe as a whole. Detecting metals and assessing their relative and absolute abundances and energetics can thus be used to trace the evolution of these cosmic components. The scope of this paper is to highlight the most important open astrophysical problems that will be central in the next decades and for which a deep understanding of the Universe’s wandering metals, their physical and kinematical states, and their chemical composition represents the only viable solution. The majority of these studies can only be efficiently performed through High Resolution Spectroscopy in the soft X-ray band.

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Circum-nuclear molecular disks: Role in AGN fueling and feedback

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320001544 ◽

2019 ◽

Vol 15 (S359) ◽

pp. 312-317

Author(s):

Francoise Combes

Keyword(s):

Black Hole ◽

Angular Momentum ◽

High Resolution ◽

Large Scale ◽

Active Galaxy ◽

Small Scale ◽

Massive Black Hole ◽

Molecular Outflows ◽

Molecular Outflow

AbstractGas fueling AGN (Active Galaxy Nuclei) is now traceable at high-resolution with ALMA (Atacama Large Millimeter Array) and NOEMA (NOrthern Extended Millimeter Array). Dynamical mechanisms are essential to exchange angular momentum and drive the gas to the super-massive black hole. While at 100pc scale, the gas is sometimes stalled in nuclear rings, recent observations reaching 10pc scale (50mas), may bring smoking gun evidence of fueling, within a randomly oriented nuclear gas disk. AGN feedback is also observed, in the form of narrow and collimated molecular outflows, which point towards the radio mode, or entrainment by a radio jet. Precession has been observed in a molecular outflow, indicating the precession of the radio jet. One of the best candidates for precession is the Bardeen-Petterson effect at small scale, which exerts a torque on the accreting material, and produces an extended disk warp. The misalignment between the inner and large-scale disk, enhances the coupling of the AGN feedback, since the jet sweeps a large part of the molecular disk.

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Repeated Imaging of Massive Black Hole Binary Orbits with Millimeter Interferometry: Measuring Black Hole Masses and the Hubble Constant

The Astrophysical Journal ◽

10.3847/1538-4357/aad413 ◽

2018 ◽

Vol 863 (2) ◽

pp. 185 ◽

Cited By ~ 9

Author(s):

Daniel J. D’Orazio ◽

Abraham Loeb

Keyword(s):

Black Hole ◽

Hubble Constant ◽

Massive Black Hole ◽

Black Hole Binary ◽

Black Hole Masses

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Central Black Hole Masses in Active Galactic Nuclei Inferred from X‐Ray Variability

The Astrophysical Journal ◽

10.1086/305736 ◽

1998 ◽

Vol 500 (2) ◽

pp. 642-659 ◽

Cited By ~ 72

Author(s):

Kiyoshi Hayashida ◽

Sigenori Miyamoto ◽

Shunji Kitamoto ◽

Hitoshi Negoro ◽

Hajime Inoue

Keyword(s):

Black Hole ◽

Active Galactic Nuclei ◽

Galactic Nuclei ◽

Central Black Hole ◽

X Ray ◽

Black Hole Masses

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Oscillator strength study of the excitations of valence-shell of C2H2 by high-resolution inelastic x-ray scattering

Chinese Physics B ◽

10.1088/1674-1056/ac422e ◽

2021 ◽

Author(s):

Qiang Sun ◽

Ya-Wei Liu ◽

Yuan-Chen Xu ◽

Li-Han Wang ◽

Tian-Jun Li ◽

...

Keyword(s):

High Resolution ◽

Theoretical Models ◽

High Energy ◽

Oscillator Strengths ◽

Electron Collision ◽

Valence Shell ◽

X Ray ◽

X Ray Scattering ◽

Theoretical Results ◽

Ray Scattering

Abstract The oscillator strengths of the valence-shell excitations of C2H2 are extremely important for testing theoretical models and studying interstellar gases. In this study, the high-resolution inelastic x-ray scattering (IXS) method is adopted to determine the generalized oscillator strengths (GOSs) of the valence-shell excitations of C2H2 at a photon energy of 10 keV. The GOSs are extrapolated to their zero limit to obtain the corresponding optical oscillator strengths (OOSs). Through taking a completely different experimental method of the IXS, the present results offer the high energy limit for electron collision to satisfy the first Born approximation (FBA) and cross-check the previous experimental and theoretical results independently. The comparisons indicate that an electron collision energy of 1500 eV is not enough for C2H2 to satisfy the FBA for the large squared momentum transfer, and the line saturation effect limits the accuracy of the OOSs measured by the photoabsorption method.

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Probing black hole accretion tracks, scaling relations, and radiative efficiencies from stacked X-ray active galactic nuclei

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3522 ◽

2019 ◽

Vol 493 (1) ◽

pp. 1500-1511 ◽

Cited By ~ 9

Author(s):

Francesco Shankar ◽

David H Weinberg ◽

Christopher Marsden ◽

Philip J Grylls ◽

Mariangela Bernardi ◽

...

Keyword(s):

Black Holes ◽

Black Hole ◽

Selection Bias ◽

Stellar Mass ◽

Supermassive Black Holes ◽

Independent Evidence ◽

X Ray ◽

Black Hole Accretion ◽

Black Hole Masses ◽

Hole Accretion

ABSTRACT The masses of supermassive black holes at the centres of local galaxies appear to be tightly correlated with the mass and velocity dispersions of their galactic hosts. However, the local Mbh–Mstar relation inferred from dynamically measured inactive black holes is up to an order-of-magnitude higher than some estimates from active black holes, and recent work suggests that this discrepancy arises from selection bias on the sample of dynamical black hole mass measurements. In this work, we combine X-ray measurements of the mean black hole accretion luminosity as a function of stellar mass and redshift with empirical models of galaxy stellar mass growth, integrating over time to predict the evolving Mbh–Mstar relation. The implied relation is nearly independent of redshift, indicating that stellar and black hole masses grow, on average, at similar rates. Matching the de-biased local Mbh–Mstar relation requires a mean radiative efficiency ε ≳ 0.15, in line with theoretical expectations for accretion on to spinning black holes. However, matching the ‘raw’ observed relation for inactive black holes requires ε ∼ 0.02, far below theoretical expectations. This result provides independent evidence for selection bias in dynamically estimated black hole masses, a conclusion that is robust to uncertainties in bolometric corrections, obscured active black hole fractions, and kinetic accretion efficiency. For our fiducial assumptions, they favour moderate-to-rapid spins of typical supermassive black holes, to achieve ε ∼ 0.12–0.20. Our approach has similarities to the classic Soltan analysis, but by using galaxy-based data instead of integrated quantities we are able to focus on regimes where observational uncertainties are minimized.

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Discovery of a New X-ray Transient in Scorpius GRO J1655-40 ≡ X-ray Nova Scorpii 1994

Symposium - International Astronomical Union ◽

10.1017/s0074180900055820 ◽

1996 ◽

Vol 165 ◽

pp. 363-367

Author(s):

W.S. Paciesas ◽

S.N. Zhang ◽

B.C. Rubin ◽

B.A. Harmon ◽

C.A. Wilson ◽

...

Keyword(s):

Black Hole ◽

High Resolution ◽

Power Law ◽

Radio Observations ◽

X Ray ◽

Black Hole Candidate ◽

Radio Jets ◽

Transient Source ◽

Galactic Source ◽

Photon Index

A bright transient X-ray source, GRO J1655-40 (X-ray Nova Scorpii 1994) was discovered with BATSE (the Burst and Transient Source Experiment) in late July 1994. More recently, the source also became a strong radio emitter, its rise in the radio being approximately anti-correlated with a decline in the hard X-ray intensity. High-resolution radio observations subsequent to this symposium showed evidence for superluminally expanding jets. Since the hard X-ray emission extends to at least 200 keV and we find no evidence of pulsations, we tentatively classify the source as a black-hole candidate. However, its hard X-ray spectrum is unusually steep (power-law photon index α ≃ −3) relative to most other black-hole candidates. In this regard, it resembles GRS 1915+105, the first galactic source to show superluminal radio jets.

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X-Ray Observations of M32 with ASCA

Symposium - International Astronomical Union ◽

10.1017/s0074180900115190 ◽

1998 ◽

Vol 188 ◽

pp. 291-292

Author(s):

T. Toneri ◽

K. Hayashida ◽

M. Loewenstein

Keyword(s):

Black Hole ◽

Mass Concentration ◽

Elliptical Galaxy ◽

Broad Band ◽

The Other ◽

Central Black Hole ◽

Massive Black Hole ◽

X Ray ◽

Eddington Limit

M32 is the nearest dwarf elliptical galaxy. Its center is known to have a mass concentration of 3 × 106 M⊙, which is usually interpreted as an evidence of a super massive black hole. We observed M32 with ASCA two times in July and August of 1996. An X-ray source was detected at the center of M32 and its first broad-band X-ray spectra were obtained. ASCA observations of M32 limit the activity of the central black hole to be less than 10−6 times of the Eddington limit. We also found two other bright sources within 12 arcmin from the M32 center. One is the newly appeared X-ray source and the other is G144. In this paper, we summarize the results on the new source and G144. For M32, please refer to the publication (Loewenstein et al. 1997).

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