scholarly journals The Origin of The Soft X-Ray Excess in the Seyfert 1.5 Galaxy ESO 362-G18

2021 ◽  
Author(s):  
xiaogu zhong ◽  
Jiancheng Wang
Keyword(s):  
Spectral Analysis ◽  
Hybrid Model ◽  
Temporal Frequency ◽  
Observation Data ◽  
X Ray ◽  
Fit Statistics ◽  
Reflection Model ◽  
Time Average ◽  
Moderate Scale ◽  
Reflection Models

Abstract We review the Seyfert 1.5 Galaxy ESO 362-G18 for exploring the origin of the soft X-ray excess. The Warm Corona and Relativistic Reflection models are two main scenarios to interpret the soft X-ray excess in AGNs at present. We use the simultaneous X-ray observation data of XMM-Newton and NuSTAR on Sep. 24th, 2016 to perform spectral analysis in two steps. First, we analyze the time-average spectra by using Warm Corona and Relativistic Reflection models. Moreover, we also explore the Hybrid model, Double Reflection model and Double Warm Corona model. We find that both of Warm Corona and Relativistic Reflection models can interpret the time-average spectra well but cannot be distinguished easily based on the time-averaged spectra fit statistics. Second, we add the RMS and covariance spectra to perform the spectral analysis with time-average spectra. The result shows that the warm corona could reproduce all of these spectra well. The the hot, optical thin corona and neutral distant reflection will increase their contribution with the temporal frequency, meaning that the corona responsible for X-ray continuum comes from the inner compact X-ray region and the neutral distant reflection is made of some moderate scale neutral clumps.

scholarly journals A detailed study on the reflection component for the black hole candidate MAXI J1836−194

2020 ◽  
Vol 493 (2) ◽  
pp. 2178-2187
Author(s):  
Yanting Dong ◽  
Javier A García ◽  
Zhu Liu ◽  
Xueshan Zhao ◽  
Xueying Zheng ◽  
...  
Keyword(s):  
Black Hole ◽  
Spectral Analysis ◽  
Primary Source ◽  
Ionization State ◽  
X Ray ◽  
Black Hole Candidate ◽  
Reflection Model ◽  
Iron Abundance ◽  
Reflection Component ◽  
Ionization Gradient

ABSTRACT We present a detailed spectral analysis of the black hole candidate MAXI J1836−194. The source was caught in the intermediate state during its 2011 outburst by Suzaku and RXTE. We jointly fit the X-ray data from these two missions using the relxill model to study the reflection component, and a steep inner emissivity profile indicating a compact corona as the primary source is required in order to achieve a good fit. In addition, a reflection model with a lamp-post configuration (relxilllp), which is normally invoked to explain the steep emissivity profile, gives a worse fit and is excluded at 99 per cent confidence level compared to relxill. We also explore the effect of the ionization gradient on the emissivity profile by fitting the data with two relativistic reflection components, and it is found that the inner emissivity flattens. These results may indicate that the ionization state of the disc is not constant. All the models above require a supersolar iron abundance higher than ∼4.5. However, we find that the high-density version of reflionx can describe the same spectra even with solar iron abundance well. A moderate rotating black hole (a* = 0.84–0.94) is consistently obtained by our models, which is in agreement with previously reported values.

scholarly journals Multi-epoch X-ray spectral analysis of the narrow-line Seyfert 1 galaxy Mrk 478

2019 ◽  
Vol 489 (4) ◽  
pp. 5398-5412 ◽  
Author(s):  
S G H Waddell ◽  
L C Gallo ◽  
A G Gonzalez ◽  
S Tripathi ◽  
A Zoghbi
Keyword(s):  
Power Law ◽  
Emission Feature ◽  
Spectral Shape ◽  
Physical Models ◽  
Data Sets ◽  
Narrow Line ◽  
Coronal Emission ◽  
X Ray ◽  
Reflection Model ◽  
Reflection Models

ABSTRACT A multi-epoch X-ray spectral and variability analysis is conducted for the narrow-line Seyfert 1 (NLS1) active galactic nucleus (AGN) Mrk 478. All available X-ray data from XMM–Newton and Suzaku satellites, spanning from 2001 to 2017, are modelled with a variety of physical models, including partial covering, soft Comptonization, and blurred reflection, to explain the observed spectral shape and variability over the 16 yr. All models are a similar statistical fit to the data sets, though the analysis of the variability between data sets favours the blurred reflection model. In particular, the variability can be attributed to changes in flux of the primary coronal emission. Different reflection models fit the data equally well, but differ in interpretation. The use of reflionx predicts a low disc ionization and power law dominated spectrum, while relxill predicts a highly ionized and blurred reflection dominated spectrum. A power law dominated spectrum might be more consistent with the normal X-ray-to-UV spectral shape (αox). Both blurred reflection models suggest a rapidly spinning black hole seen at a low inclination angle, and both require a sub-solar (∼0.5) abundance of iron. All physical models require a narrow emission feature at $6.7{\rm \, keV}$ likely attributable to Fe xxv emission, while no evidence for a narrow $6.4{\rm \, keV}$ line from neutral iron is detected.

scholarly journals Estimation of Wear Resistance for Multilayer Coatings Obtained by Nitrogenchroming

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1153
Author(s):  
Ivan Pavlenko ◽  
Jozef Zajac ◽  
Nadiia Kharchenko ◽  
Ján Duplák ◽  
Vitalii Ivanov ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Spectral Analysis ◽  
Friction Coefficient ◽  
Cutting Tools ◽  
Wear Intensity ◽  
Maximum Amount ◽  
Multilayer Coatings ◽  
Wear Depth ◽  
X Ray ◽  
Machine Parts

This article deals with improving the wear resistance of multilayer coatings as a fundamental problem in metal surface treatment, strengthening elements of cutting tools, and ensuring the reliability of machine parts. It aims to evaluate the wear depth for multilayer coatings by the mass loss distribution in layers. The article’s primary purpose is to develop a mathematical method for assessing the value of wear for multilayer steel-based coatings. The study material is a multilayer coating applied to steel DIN C80W1. The research was performed using up-to-date laboratory equipment. Nitrogenchroming has been realized under overpressure in two successive stages: nitriding for 36 h at temperature 540 °C and chromizing during 4 h at temperature 1050 °C. The complex analysis included several options: X-ray phase analysis, local micro-X-ray spectral analysis, durometric analysis, and determination of wear resistance. These analyses showed that after nitrogenchroming, the three-layer protective coating from Cr23C6, Cr7C3, and Cr2N was formed on the steel surface. Spectral analysis indicated that the maximum amount of chromium 92.2% is in the first layer from Cr23C6. The maximum amount of carbon 8.9% characterizes the layer from Cr7C3. Nitrogen is concentrated mainly in the Cr2N layer, and its maximum amount is 9.4%. Additionally, it was determined that the minimum wear is typical for steel DIN C80W1 after nitrogenchroming. The weight loss of steel samples by 25 mg was obtained. This value differs by 3.6% from the results evaluated analytically using the developed mathematical model of wear of multilayer coatings after complex metallization of steel DIN C80W1. As a result, the impact of the loading mode on the wear intensity of steel was established. As the loading time increases, the friction coefficient of the coated samples decreases. Among the studied samples, plates from steel DIN C80W1 have the lowest friction coefficient after nitrogenchroming. Additionally, a linear dependence of the mass losses on the wearing time was obtained for carbide and nitride coatings. Finally, an increase in loading time leads to an increase in the wear intensity of steels after nitrogenchroming. The achieved scientific results are applicable in developing methods of chemical-thermal treatment, improving the wear resistance of multilayer coatings, and strengthening highly loaded machine parts and cutting tools.

scholarly journals Spectral analysis of x-ray emission created by intense laser irradiation of copper materialsa)

2012 ◽  
Vol 83 (10) ◽  
pp. 10E114 ◽  
Author(s):  
C. M. Huntington ◽  
C. C. Kuranz ◽  
G. Malamud ◽  
R. P. Drake ◽  
H.-S. Park ◽  
...  
Keyword(s):  
Spectral Analysis ◽  
Laser Irradiation ◽  
Intense Laser ◽  
X Ray

scholarly journals Soft X-ray absorption spectra in the CK region of carbon black and spectral analysis using the discrete variational Xα method

TANSO ◽  
2009 ◽  
Vol 2009 (236) ◽  
pp. 2-8 ◽  
Author(s):  
Yasuji Muramatsu ◽  
Ryusuke Harada ◽  
Muneyuki Motoyama ◽  
Eric M. Gullikson
Keyword(s):  
Spectral Analysis ◽  
Carbon Black ◽  
Absorption Spectra ◽  
X Ray ◽  
X Ray Absorption

scholarly journals The ultrafast outflow of WKK 4438: Suzaku and NuSTAR X-ray spectral analysis

2018 ◽  
Vol 481 (1) ◽  
pp. 639-644 ◽  
Author(s):  
Jiachen Jiang (姜嘉陈) ◽  
Dominic J Walton ◽  
Michael L Parker ◽  
Andrew C Fabian
Keyword(s):  
Spectral Analysis ◽  
X Ray

X-ray spectral analysis — new aspects

1987 ◽  
Vol 327 (1) ◽  
pp. 7-8 ◽  
Author(s):  
R. Klockenkämper
Keyword(s):  
Spectral Analysis ◽  
X Ray

scholarly journals Magnetar X-ray emission mechanisms

2012 ◽  
Vol 8 (S291) ◽  
pp. 160-160
Author(s):  
Silvia Zane
Keyword(s):  
Spectral Analysis ◽  
Physical Interpretation ◽  
Spectral Properties ◽  
Gamma Ray ◽  
X Ray ◽  
Spectral Components ◽  
Self Consistent ◽  
Photon Index ◽  
Index 2 ◽  
Surface Fields

AbstractSoft gamma-ray repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are peculiar X-ray sources which are believed to be magnetars: ultra-magnetized neutron stars which emission is dominated by surface fields (often in excess of 1E14 G, i.e. well above the QED threshold).Spectral analysis is an important tool in magnetar astrophysics since it can provide key information on the emission mechanisms. The first attempts at modelling the persistent (i.e. outside bursts) soft X-ray (¡10 keV) spectra of AXPs proved that a model consisting of a blackbody (kT 0.3-0.6 keV) plus a power-law (photon index 2-4) could successfully reproduce the observed emission. Moreover, INTEGRAL observations have shown that, while in quiescence, magnetars emit substantial persistent radiation also at higher energies, up to a few hundreds of keV. However, a convincing physical interpretation of the various spectral components is still missing.In this talk I will focus on the interpretation of magnetar spectral properties during quiescence. I will summarise the present status of the art and the currents attempts to model the broadband persistent emission of magnetars (from IR to hard Xrays) within a self consistent, physical scenario.

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