Abstract
The soft excess is a significant emission component in the soft (<1 keV) X-ray spectra of many active galactic nuclei (AGN). It has been explained by disk reflection, a warm corona, and ...other models. Understanding its origin is crucial for the energy budget of AGN emission, and for using it to study the inner accretion disk. Here, we track the weeks-to-months variability of several AGN that show different levels of soft excess strength with NICER. We use the variability timescales to compare the relative size of the soft excess emission region to the corona producing the hard X-ray emission above 1 keV. We find that the size of the soft excess emission region relative to the corona is not the same for the three sources studied. For TON S180, the soft excess region is comparable in size to the hard corona. While for MRK 335 and 1H0707-495, the soft excess region is larger than the corona by a factor of 2–4. This is the first time the relative sizes are quantified independently of the assumptions of the spectral models.
NGC 4151 is the brightest Seyfert 1 nucleus in X-rays. It was the first object to show short time delays in the Fe K band, which were attributed to relativistic reverberation, providing a new tool ...for probing regions at the black hole scale. Here we report the results of a large XMM-Newton campaign in 2015 to study these short delays further. Analyzing high-quality data that span timescales between hours and decades, we find that neutral and ionized absorption contributes significantly to the spectral shape. Accounting for their effects, we find no evidence for a relativistic reflection component, contrary to early work. Energy-dependent lags are significantly measured in the new data, but with an energy profile that does not resemble a broad iron line, in contrast to the old data. The complex lag-energy spectra, along with the lack of strong evidence for a relativistic spectral component, suggest that the energy-dependent lags are produced by absorption effects. The long-term spectral variations provide new details on the variability of the narrow Fe K line. We find that its variations are correlated with, and delayed with respect to, the primary X-ray continuum. We measure a delay of days, implying an origin in the inner broad-line region (BLR). The delay is half the Hβ line delay, suggesting a geometry that differs slightly from the optical BLR.
Abstract
X-ray reverberation mapping has emerged as a new tool to probe accretion in active galactic nuclei (AGN), providing a potentially powerful probe of accretion at the black hole scale. The ...lags, along with relativistic spectral signatures are often interpreted in light of the lamppost model. Focusing specifically on testing the prediction of the relativistic reverberation model, we have targeted several of the brightest Seyfert Galaxies in X-rays with different observing programs. Here, we report the results from two large campaigns with NuSTAR targeting MCG-5-23-16 and SWIFT J2127.4+5654 to test the model predictions in the 3–50 keV band. These are two of three sources that showed indications of a delayed Compton hump in early data. With triple the previously analyzed exposures, we find no evidence for relativistic reverberation in MCG-5-23-16, and the energy-dependent lags are consistent with a log-linear continuum. In SWIFT J2127.4+5654, although a continuum-only model explains the data, the relativistic reverberation model provides a significant improvement to the energy and frequency-dependent lags, but with parameters that are not consistent with the time-averaged spectrum. This adds to mounting evidence showing that the lag data is not consistent with a static lamppost model.
We use archival XMM-Newton observations of Ark 564 and Mrk 335 to calculate the frequency-dependent time lags for these two well-studied sources. We discover high-frequency Fe K lags in both sources, ...indicating that the red wing of the line precedes the rest-frame energy by roughly 100 and 150 s for Ark 564 and Mrk 335, respectively. Including these two new sources, Fe K reverberation lags have been observed in seven Seyfert galaxies. We examine the low-frequency lag-energy spectrum, which is smooth, and shows no feature of reverberation, as would be expected if the low-frequency lags were produced by distant reflection off circumnuclear material. The clear differences in the low- and high-frequency lag-energy spectra indicate that the lags are produced by two distinct physical processes. Finally, we find that the amplitude of the Fe K lag scales with black hole mass for these seven sources, consistent with a relativistic reflection model where the lag is the light travel delay associated with reflection of continuum photons off the inner disc.
X-ray reverberation, where light-travel time delays map out the compact geometry around the inner accretion flow in supermassive black holes, has been discovered in several of the brightest, most ...variable and well-known Seyfert galaxies. In this work, we expand the study of X-ray reverberation to all Seyfert galaxies in the XMM–Newton archive above a nominal rms variability and exposure level (a total of 43 sources). Approximately 50 per cent of sources exhibit iron K reverberation, in that the broad iron K emission line responds to rapid variability in the continuum. We also find that on long time-scales, the hard band emission lags behind the soft band emission in 85 per cent of sources. This ‘low-frequency hard lag’ is likely associated with the coronal emission, and so this result suggests that most sources with X-ray variability show intrinsic variability from the nuclear region. We update the known iron K lag amplitude versus black hole mass relation, and find evidence that the height or extent of the coronal source (as inferred by the reverberation time delay) increases with mass accretion rate.
Recent X-ray observations have enabled the study of reverberation delays in active galactic nuclei (AGN) for the first time. All the detections so far are in sources with a strong soft excess, and ...the measured delay is between the hard (1-3 keV) direct continuum and the soft excess (0.5-1 keV), interpreted as the reflection continuum smeared by relativistic effects. There is however an inherent ambiguity in identifying and studying the details of the lines in the soft excess. Here we report the first detection of reverberation in the iron K band in any AGN. Using XMM-Newton observations of NGC 4151, we find delays of the order of 2000 s on time-scales of 105 s between the
keV band and the
and
keV bands, with a broad lag profile resembling a relativistically broadened iron line. The peak of the lag spectra shifts to lower energies at higher frequencies, consistent with the red wing of the line being emitted at smaller radii, as expected from reflection off the inner accretion disc. This is a first detection of a broad iron line using timing studies.
The recent detection of X-ray reverberation lags, especially in the Fe Kα line region, around active galactic nuclei (AGN) has opened up the possibility of studying the time-resolved response ...(reflection) of hard X-rays from the accretion disc around supermassive black holes. Here, we use general relativistic transfer functions for reflection of X-rays from a point source located at some height above the black hole to study the time lags expected as a function of frequency and energy in the Fe Kα line region. We explore the models and the dependence of the lags on key parameters such as the height of the X-ray source, accretion disc inclination, black hole spin and black hole mass. We then compare these models with the observed frequency- and energy-dependence of the Fe Kα line lag in NGC 4151. Assuming the optical reverberation mapping mass of 4.6 × 107 M, we get a best fit to the lag profile across the Fe Kα line in the frequency range (1-2) × 10− 5 Hz for an X-ray source located at a height
with a maximally spinning black hole and an inclination i < 30°.
A substantial increase in the knowledge of the genetic basis of cardiomyopathy has occurred, and noninvasive phenotypic characterization has become significantly more sophisticated. ...the American ...Heart Association (AHA) (7) and the European Society of Cardiology (ESC) (8) in the last decade have proposed revisions to the classification of cardiomyopathic disorders. In the ESC 2008 classification, the cardiomyopathy was defined as familial when present in more than 1 member of the family.\n Disease MIM# Phenotype Inheritance Age of Onset Disease Gene Cardiac Phenotype Extracardiac Markers/Involvement of Other Organs Treatment Multiple acyl-CoA dehydrogenase deficiency Glutaric acidemia IIA 231680 AR Neonatal ETFA DCM, neonatal Nervous, skeletal, muscle, liver, kidney (often polycystic), metabolic acidosis, hypoglycemia  Glutaric acidemia IIB 231680 AR Neonatal, childhood ETFB Sudden neonatal death Nervous, skeletal, muscle, liver  Glutaric acidemia IIC 231680 AR Childhood to adult ETFDH DCM Nervous, skeletal, muscle, liver, kidney (often polycystic), lung, metabolic acidosis, hypoglycemia  Primary, systemic, carnitine transporter deficiency 212140 AR Childhood to adult SLC22A5 DCM, HCM < Total plasma carnitine, hypoketotic hypoglycemia, hepatomegaly, elevated transaminases, and hyperammonemia in infants; skeletal myopathy, > creatine kinase, in childhood; cardiomyopathy, arrhythmias, or fatigability in adulthood Carnitine supplementation Chanarin-Dorfman syndrome (NLSD-I) 275630 AR Childhood to adult ABHD5 DCM Skin (ichthyosiform erythroderma), liver, muscle, nervous (with possible MR), ocular Suggested: diet low in long-chain fatty acids; retinoids for skin in patients w/o liver dysfunction Neutral lipid storage disease with myopathy (NLSD-M) 610717 AR Childhood to adult PNPLA2low * DCM Myopathy  Table 5 Major Lipid Storage Disorders With Possible Myocardial Involvement MR = mental retardation; other abbreviations as in Table 1.
ABSTRACT We report on a 120 ks Chandra/HETG spectrum of the black hole GRS 1915+105. The observation was made during an extended and bright soft state in 2015 June. An extremely rich disk wind ...absorption spectrum is detected, similar to that observed at lower sensitivity in 2007. The very high resolution of the third-order spectrum reveals four components to the disk wind in the Fe K band alone; the fastest has a blueshift of v = 0.03 c . Broadened re-emission from the wind is also detected in the first-order spectrum, giving rise to clear accretion disk P Cygni profiles. Dynamical modeling of the re-emission spectrum gives wind launching radii of r 10 2 − 4 GM / c 2 . Wind density values of n 10 13 − 16 cm − 3 are then required by the ionization parameter formalism. The small launching radii, high density values, and inferred high mass outflow rates signal a role for magnetic driving. With simple, reasonable assumptions, the wind properties constrain the magnitude of the emergent magnetic field to be B 10 3 − 4 G if the wind is driven via magnetohydrodynamic (MHD) pressure from within the disk and B 10 4 − 5 G if the wind is driven by magnetocentrifugal acceleration. The MHD estimates are below upper limits predicted by the canonical -disk model. We discuss these results in terms of fundamental disk physics and black hole accretion modes.
Abstract
GRS 1915+105 is a stellar-mass black hole that is well known for exhibiting at least 12 distinct classes of X-ray variability and correlated multi-wavelength behavior. Despite such ...extraordinary variability, GRS 1915+105 remained one of the brightest sources in the X-ray sky. However, in early 2019, the source became much fainter, apparently entering a new accretion state. Here, we report the results of an extensive, year-long monitoring campaign of GRS 1915+105 with the Neil Gehrels Swift Observatory. During this interval, the flux of GRS 1915+105 gradually diminished; the observed count rate eventually dropped by two orders of magnitude. Simple but robust spectral fits to these monitoring observations show that this new state results from the combination of a dramatic and persistent increase in internal obscuration, and a reduced mass accretion rate. The internal obscuration is the dominant effect, with a median value of
N
H
= 7 × 10
23
cm
−2
. In a number of observations, the source appears to be Compton-thick. We suggest that this state should be identified as the “obscured state,” and discuss the implications of this new (or rarely observed) accretion mode for black holes across the mass scale.
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