Model for the X-ray emission in the jets and hot spots of radio galaxies

2001 ◽  
Author(s):  
Charles D. Dermer
Keyword(s):  
Hot Spots ◽  
Radio Galaxies ◽  
X Ray

scholarly journals Extended X-Ray Emission around FR II Radio Galaxies: Hot Spots, Lobes, and Galaxy Clusters

2021 ◽  
Vol 252 (2) ◽  
pp. 31
Author(s):  
A. Jimenez-Gallardo ◽  
F. Massaro ◽  
A. Paggi ◽  
R. D’Abrusco ◽  
M. A. Prieto ◽  
...  
Keyword(s):  
Galaxy Clusters ◽  
Hot Spots ◽  
Radio Galaxies ◽  
X Ray

scholarly journals X-ray emission from the nuclei, lobes and hot-gas environments of two FR II radio galaxies

2004 ◽  
Vol 353 (3) ◽  
pp. 879-889 ◽  
Author(s):  
J. H. Croston ◽  
M. Birkinshaw ◽  
M. J. Hardcastle ◽  
D. M. Worrall
Keyword(s):  
Radio Galaxies ◽  
X Ray ◽  
Hot Gas

scholarly journals Improvement of Spatial Modeling of Cr, Pb, Cd, As and Ni in Soil Based on Portable X-ray Fluorescence (PXRF) and Geostatistics: A Case Study in East China

2019 ◽  
Vol 16 (15) ◽  
pp. 2694 ◽  
Author(s):  
Xia ◽  
Hu ◽  
Shao ◽  
Xu ◽  
Zhou ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Hot Spots ◽  
Ordinary Kriging ◽  
Eastern China ◽  
Indicator Kriging ◽  
Polluted Water ◽  
X Ray ◽  
Soil Heavy Metals ◽  
Metals Pollution ◽  
Heavy Metals Pollution

To verify the feasibility of portable X-ray fluorescence (PXRF) for rapidly analyzing, assessing and improving soil heavy metals mapping, 351 samples were collected from Fuyang District, Hangzhou City, in eastern China. Ordinary kriging (OK) and co-ordinary kriging (COK) combined with PXRF measurements were used to explore spatial patterns of heavy metals content in the soil. The Getis-Ord index was calculated to discern hot spots of heavy metals. Finally, multi-variable indicator kriging was conducted to obtain a map of multi-heavy metals pollution. The results indicated Cd is the primary pollution element in Fuyang, followed by As and Pb. Application of PXRF measurements as covariates in COK improved model accuracy, especially for Pb and Cd. Heavy metals pollution hot spots were mainly detected in northern Fuyang and plains along the Fuchun River in southern Fuyang because of mining, industrial and traffic activities, and irrigation with polluted water. Area with high risk of multi-heavy metals pollution mainly distributed in plain along the Fuchun River and the eastern Fuyang. These findings certified the feasibility of using PXRF as an efficient and reliable method for soil heavy metals pollution assessment and mapping, which could contribute to reduce the cost of surveys and pollution remediation.

Study on Linear Segregation of ZL205A Alloy

2021 ◽  
Vol 1020 ◽  
pp. 8-12
Author(s):  
Wu Hu ◽  
Ke Zhu ◽  
Meng Wang ◽  
Wei Dong Huang ◽  
Jian Min Zeng
Keyword(s):  
Aluminum Alloy ◽  
Wall Thickness ◽  
Hot Spots ◽  
Energy Dispersive Spectrometer ◽  
High Strength ◽  
X Ray ◽  
Thermal Cracks ◽  
Zl205a Alloy ◽  
Solidification Speed ◽  
Scanning Electron

Linear segregation of high strength aluminum alloy ZL205A castings were studied by X-ray Nondestructive testing, scanning electron microscope and energy dispersive spectrometer. It is found that the linear segregation occurs at the large wall thickness of the casting and/or at the place where the wall thickness is in transition. Segregation element is mainly Cu, which exists as compound θ (Al2Cu) phase. The formation of linear segregation is related to the flow of Cu-rich melt in the late solidification period, while the occurrence of thermal cracks promotes the formation of linear segregation. The formation of linear segregation of the casting can be effectively prevented by eliminating hot spots of the casting, refining crystal grains and increasing solidification speed of the casting.

scholarly journals The relation between the diffuse X-ray luminosity and the radio power of the central AGN in galaxy groups

2020 ◽  
Vol 497 (2) ◽  
pp. 2163-2174
Author(s):  
T Pasini ◽  
M Brüggen ◽  
F de Gasperin ◽  
L Bîrzan ◽  
E O’Sullivan ◽  
...  
Keyword(s):  
Radio Emission ◽  
Galaxy Clusters ◽  
Active Galactic Nucleus ◽  
Statistical Tests ◽  
Control Sample ◽  
Radio Galaxies ◽  
Very Large Array ◽  
X Ray ◽  
Galaxy Groups ◽  
Hydrodynamical Simulations

ABSTRACT Our understanding of how active galactic nucleus feedback operates in galaxy clusters has improved in recent years owing to large efforts in multiwavelength observations and hydrodynamical simulations. However, it is much less clear how feedback operates in galaxy groups, which have shallower gravitational potentials. In this work, using very deep Very Large Array and new MeerKAT observations from the MIGHTEE survey, we compiled a sample of 247 X-ray selected galaxy groups detected in the COSMOS field. We have studied the relation between the X-ray emission of the intra-group medium and the 1.4 GHz radio emission of the central radio galaxy. For comparison, we have also built a control sample of 142 galaxy clusters using ROSAT and NVSS data. We find that clusters and groups follow the same correlation between X-ray and radio emission. Large radio galaxies hosted in the centres of groups and merging clusters increase the scatter of the distribution. Using statistical tests and Monte Carlo simulations, we show that the correlation is not dominated by biases or selection effects. We also find that galaxy groups are more likely than clusters to host large radio galaxies, perhaps owing to the lower ambient gas density or a more efficient accretion mode. In these groups, radiative cooling of the intra-cluster medium could be less suppressed by active galactic nucleus heating. We conclude that the feedback processes that operate in galaxy clusters are also effective in groups.

scholarly journals VLA observations of 20 FR II radio sources at 8.4 GHz

2019 ◽  
Vol 364 (10) ◽  
Author(s):  
Ilias Fernini
Keyword(s):  
High Resolution ◽  
Hot Spots ◽  
Radio Galaxies ◽  
Class Ii ◽  
Outer Edge ◽  
Radio Sources ◽  
Large Sample ◽  
Contour Maps ◽  
Surrounding Environment

Abstract We report the last observational paper of hot spots for 20 Fanaroff-Riley class II (FR II) sources. These sources are part of a large sample of 98 FR II to study the unification scheme of FR II radio galaxies (RGs) and quasars (QSRs) using the hotspots (HSs) location and morphology. High-resolution VLA observations at 8.4 GHz were conducted for the whole sample. The investigation of HSs properties in FR II radio sources is essential for a better understanding of the dynamics related to the objects and their impact on the surrounding environment. HSs were classified into edged and recessed types, where the former is located at a radio lobe’s outer edge, and the latter is embedded within the lobe. The present sub-sample contains 12 RGs and 8 QSRs. Radio contour maps for each source were presented using the VLA in its A and B configurations. In total, we have identified 18 HSs for these 20 radio sources. The 12 RGs possess 8 edged HSs and 2 recessed HSs. The 8 QSRs possess 6 edged HSs and 2 recessed HSs. Out of the 14 edged HSs, RGs and QSRs possess $\sim57\%$∼57% and $\sim43\%$∼43%, respectively. A thorough morphological discussion of the 20 sources with their HSs is presented in the present work.

scholarly journals The Parsec-Scale Central Components of FR I Radio Galaxies

2001 ◽  
Vol 205 ◽  
pp. 74-75
Author(s):  
Preeti Kharb ◽  
Prajval Shastri
Keyword(s):  
Radio Galaxies ◽  
X Ray

We present results of our study of the parsec-scale components of radio galaxies as observed at radio, optical and X-ray wavelengths, in the framework of the Unified Scheme.

Clumped X-ray emission around radio galaxies in clusters: New tools for investigating cluster evolution

1994 ◽  
Author(s):  
J. Burns ◽  
K. Roettiger ◽  
J. Pinkney ◽  
C. Loken ◽  
S. Doe ◽  
...  
Keyword(s):  
Radio Galaxies ◽  
X Ray ◽  
Cluster Evolution

scholarly journals Luminosity Correlation of the X-ray Selected Radio-Loud AGNs

1999 ◽  
Vol 194 ◽  
pp. 306-310
Author(s):  
Q. Yuan ◽  
J. Wu ◽  
K. Huang
Keyword(s):  
Active Galactic Nuclei ◽  
Broad Band ◽  
Galactic Nuclei ◽  
Radio Galaxies ◽  
Spectral Indices ◽  
Strong Correlations ◽  
Band Energy ◽  
X Ray ◽  
Sky Survey ◽  
Bl Lacs

This paper presents a test of the luminosity correlation of the X-ray selected radio-loud Active Galactic Nuclei (AGNs), based on a large sample constructed by combining our cross-identification of southern sky sources with the radio-loud sources in the northern hemisphere given by Brinkmann et al. (1995). All sources were detected both by the ROSAT All-Sky Survey and the radio surveys at 4.85 GHz. The broad band energy distribution confirms the presence of strong correlations between luminosities in the radio, optical, and X-ray bands which differ for quasars, seyferts, BL Lacs, and radio galaxies. The tight correlations between spectral indices αox and monochromatic luminosities at 5500 Å and 4.85 GHz are also shown.

Evaluation of hot spots parameters by simple soft x-ray diagnostics

1989 ◽  
Author(s):  
A. Krejc̆í ◽  
E. Kruouský ◽  
O. Renner
Keyword(s):  
Hot Spots ◽  
X Ray
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