Hot spot radio galaxies — an introduction

1989 ◽  
pp. 1-26 ◽  
Author(s):  
Richard A. Perley
Keyword(s):  
Hot Spot ◽  
Radio Galaxies

Constraints on extragalactic-jet characteristics from lobe observations

1986 ◽  
Vol 64 (4) ◽  
pp. 378-380 ◽  
Author(s):  
Steven R. Spangler
Keyword(s):  
Hot Spot ◽  
Radio Galaxies ◽  
Large Array ◽  
Very Large Array ◽  
Upper Limits ◽  
Measured Speed ◽  
High Mach ◽  
Jet Characteristics ◽  
Double Radio Galaxies ◽  
Spot Motion

We discuss Very Large Array spectral and polarimetric observations of the lobes of luminous, double radio galaxies. These observations can provide information on the (typically undetected) jets responsible for the sources. Spectral steepening is usually observed in the lobes, with the radio spectral index increasing with distance from the hot spot. These data can be used to infer a "speed of separation" of the hot spot and lobe material. These speeds, typically 1.0 × 104–3.0 × 104 km/s, are in agreement with hydrocode models of jets, which interpret the measured speed of separation as a combination of hot-spot motion and backflow. Polarimetric observations indicate that in at least some sources, there is an undetectably small amount of internal Faraday rotation, indicating upper limits to the thermal-plasma density of a few times 10−5 cm−3 or less. These measurements are also in agreement with the numerical beam models, provided that the beam density is substantially less than that of the background medium. We conclude that the lobe observations indicate that these sources are powered by light, high-Mach-number beams.

Chandra observations of gamma-ray emitting radio galaxies

2018 ◽  
Vol 27 (10) ◽  
pp. 1844022
Author(s):  
D. Zargaryan ◽  
N. Sahakyan ◽  
H. Harutyunian
Keyword(s):  
Large Scale ◽  
Physical State ◽  
Gamma Ray ◽  
Hot Spot ◽  
Radio Galaxies ◽  
Physical Parameters ◽  
Broad Line ◽  
Large Area ◽  
Line Region ◽  
3C 120

Important information on the evolution of a jet can be obtained by comparing the physical state of the plasma at its propagation through the broad-line region (where the jet is most likely formed) into the intergalactic medium, where it starts to decelerate significantly. This approach can be fruitfully applied to sources having a large-scale jet long enough to be resolved by Chandra telescope. This is why, from the Fermi Large Area Telescope (Fermi LAT) third source catalog we have selected radio galaxies that have a knot or hot-spot structure in their large-scale jet. We compare the constraints on the physical parameters in the innermost ([Formula: see text] pc) and outer ([Formula: see text] kpc) regions of the same jet by means of a detailed multiwavelength analysis and theoretical modeling of the broadband spectra of M87, Pictor A, 3C 303, 3C 275.1, NGC 6251, 3C 207, 3C 111 and 3C 120.

3D Spectroscopy in Distant Radio Galaxies

2001 ◽  
Vol 1 ◽  
pp. 131-144
Author(s):  
B. Rocca-Volmerange
Keyword(s):  
Radio Galaxies

Mutation Spectrum in Patients with Wiskott-Aldrich Syndrome and X-linked Thrombocytopenia: Identification of Twelve Different Mutations in the WASP Gene

1996 ◽  
Vol 75 (04) ◽  
pp. 546-550 ◽  
Author(s):  
Marianne Schwartz ◽  
Albert Békássy ◽  
Mikael Donnér ◽  
Thomas Hertel ◽  
Stefan Hreidarson ◽  
...  
Keyword(s):  
Base Pair ◽  
Hot Spot ◽  
Missense Mutations ◽  
Nucleotide Substitutions ◽  
Exon 2 ◽  
Wiskott Aldrich Syndrome ◽  
Base Pair Deletion ◽  
Reliable Diagnosis ◽  
Wasp Gene ◽  
Detection Of Mutations

SummaryTwelve different mutations in the WASP gene were found in twelve unrelated families with Wiskott-Aldrich syndrome (WAS) or X-linked thrombocytopenia (XLT). Four frameshift, one splice, one nonsense mutation, and one 18-base-pair deletion were detected in seven patients with WAS. Only missense mutations were found in five patients diagnosed as having XLT. One of the nucleotide substitutions in exon 2 (codon 86) results in an Arg to Cys replacement. Two other nucleotide substitutions in this codon, R86L and R86H, have been reported previously, both giving rise to typical WAS symptoms, indicating a mutational hot spot in this codon. The finding of mutations in the WASP gene in both WAS and XLT gives further evidence of these syndromes being allelic. The relatively small size of the WASP gene facilitates the detection of mutations and a reliable diagnosis of both carriers and affected fetuses in families with WAS or XLT.

Challenges to immigrant associations and NGOs in contemporary Greece

2013 ◽  
Vol 10 (3) ◽  
pp. 342-358 ◽  
Author(s):  
Apostolos G. Papadopoulos ◽  
Christos Chalkias ◽  
Loukia-Maria Fratsea
Keyword(s):  
Civil Society ◽  
Economic Crisis ◽  
Hot Spot ◽  
Geographical Range ◽  
Legal Form ◽  
Social Actors ◽  
Governmental Organizations ◽  
Non Governmental Organizations ◽  
Migrant Integration ◽  
Concentration Patterns

The paper explores the challenges faced today, in a context of severe economic crisis, by immigrant associations (ΙΜΑs) and Non-Governmental Organizations (NGOs) in Greece. The data analysed here was collected between October 2009 and February 2010 and incorporates references to all recorded migration-related social actors operating in Greece. The paper takes into account such indicators as legal form, objectives, financial capacity and geographical range of activity, concluding with a typology of civil society actors dealing with migration issues. This study aims at informing the migration policymaking and migrant integration processes. By a spatial hot-spot clustering of IMAs and NGOs, we also illustrate the concentration patterns of civil society actors in Greece.

Sun Load Analysis and Testing on Automotive Front Lighting Products

2020 ◽  
pp. 116-122
Author(s):  
Emre Öztürk ◽  
Mehmet Aktaş ◽  
Tunç Şenyüz
Keyword(s):  
Prolonged Exposure ◽  
Hot Spot ◽  
Load Test ◽  
Angle Of Incidence ◽  
The Sun ◽  
Solar Simulator ◽  
Automotive Lighting ◽  
Inclination Angles ◽  
Plastic Parts ◽  
Load Simulation

The purpose of this research is to reach good correlation between sun load simulation and solar focusing test for exterior automotive lighting products. Light coming from sun is highly collimated (parallel rays) and focusable from lenses with concave structure. Focusing incidence leads to a hot spot on lens surrounding plastic parts which may cause melting failures at high temperature zones. Sun load simulation is performing to eliminate risk of discoloration, deformation, out gassing, coating failures and fire with prolonged exposure from field. Irradiance values in W/m2 defined in simulation as heat source depending of an angle of incidence of the sun radiation. At first step, simulation is performing with 5 degree intervals to define the critical zones then intervals decreased to 2 degree to detect the critical azimuth and inclination angles. Critical azimuth and inclination angles is checking with ray trace analysis to check the bouncing of sun rays and possible solution to eliminate focuses with design solutions. After numerical analysis to release and validate the automotive lighting products regarding the sun load test, measurement with first parts is necessary. Measurement is performing for all critical angles which have been detected at simulation with thermal camera under ultra high-collimation solar simulator. Measured temperatures are settled according to environment conditions and correlation is checking with simulations.

Accurate Systematic Hot-Spot Scoring Method and Score-Based Fixing Guidance Generation

2009 ◽  
Vol E92.A (12) ◽  
pp. 3082-3085
Author(s):  
Yonghee PARK ◽  
Junghoe CHOI ◽  
Jisuk HONG ◽  
Sanghoon LEE ◽  
Moonhyun YOO ◽  
...  
Keyword(s):  
Hot Spot ◽  
Scoring Method
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