scholarly journals HIGH-ENERGY X-RAY IMAGING OF THE PULSAR WIND NEBULA MSH 15–52: CONSTRAINTS ON PARTICLE ACCELERATION AND TRANSPORT

2014 ◽  
Vol 793 (2) ◽  
pp. 90 ◽  
Author(s):  
Hongjun An ◽  
Kristin K. Madsen ◽  
Stephen P. Reynolds ◽  
Victoria M. Kaspi ◽  
Fiona A. Harrison ◽  
...  
Keyword(s):  
Particle Acceleration ◽  
High Energy ◽  
X Ray ◽  
X Ray Imaging ◽  
Pulsar Wind

scholarly journals PULSAR WIND NEBULAE MODELING

2014 ◽  
Vol 28 ◽  
pp. 1460162 ◽  
Author(s):  
NICCOLÒ BUCCIANTINI
Keyword(s):  
High Resolution ◽  
High Energy ◽  
Clear Understanding ◽  
Strong Impact ◽  
Pulsar Magnetosphere ◽  
Pulsar Wind Nebulae ◽  
X Ray ◽  
X Ray Imaging ◽  
Dynamical Properties ◽  
Pulsar Wind

Pulsar Wind Nebulae (PWNe) are ideal astrophysical laboratories where high energy relativistic phenomena can be investigated. They are close, well resolved in our observations, and the knowledge derived in their study has a strong impact in many other fields, from AGNs to GRBs. Yet there are still unresolved issues, that prevent us from a full clear understanding of these objects. The lucky combination of high resolution X-ray imaging and numerical codes to handle the outflow and dynamical properties of relativistic MHD, has opened a new avenue of investigation that has lead to interesting progresses in the last years. Despite all of this, we do not understand yet how particles are accelerated, and the functioning of the pulsar wind and pulsar magnetosphere, that power PWNe. I will review what is now commonly known as the MHD paradigm, and in particular I will focus on various approaches that have been and are currently used to model these systems. For each I will highlight its advantages, limitations, and degree of applicability.

scholarly journals AGILE results on relativistic outflows above 100MeV

2018 ◽  
Vol 27 (10) ◽  
pp. 1844015 ◽  
Author(s):  
Carlotta Pittori
Keyword(s):  
Particle Acceleration ◽  
Energy Range ◽  
High Energy ◽  
Extreme Conditions ◽  
X Ray ◽  
Space Agency ◽  
X Ray Imaging ◽  
Agile Satellite ◽  
Radiation Processes ◽  
Italian Space Agency

We give an overview of the AGILE [Formula: see text]-ray satellite scientific highlights. AGILE is an Italian Space Agency (ASI) mission devoted to observations in the 30[Formula: see text]MeV–50[Formula: see text]GeV [Formula: see text]-ray energy range, with simultaneous X-ray imaging in the 18–60[Formula: see text]keV band. Launched in April 2007, the AGILE satellite has completed its tenth year of operations in orbit, and it is substantially contributing to improve our knowledge of the high-energy sky. Emission from cosmic sources at energies above 100[Formula: see text]MeV is intrinsically nonthermal, and the study of the wide variety of observed Galactic and extragalactic [Formula: see text]-ray sources provides a unique opportunity to test theories of particle acceleration and radiation processes in extreme conditions.

Designing high-resolution slow scan CCD-based TEM camera systems

1992 ◽  
Vol 50 (2) ◽  
pp. 946-947
Author(s):  
James F. Mancuso ◽  
William B. Maxwell ◽  
Russell E. Camp ◽  
Mark H. Ellisman
Keyword(s):  
Fiber Optics ◽  
Ccd Camera ◽  
High Energy ◽  
Phosphor Layer ◽  
X Ray ◽  
Light Production ◽  
Camera Systems ◽  
X Ray Imaging ◽  
Electron Image ◽  
Scintillating Fiber

The imaging requirements for 1000 line CCD camera systems include resolution, sensitivity, and field of view. In electronic camera systems these characteristics are determined primarily by the performance of the electro-optic interface. This component converts the electron image into a light image which is ultimately received by a camera sensor.Light production in the interface occurs when high energy electrons strike a phosphor or scintillator. Resolution is limited by electron scattering and absorption. For a constant resolution, more energy deposition occurs in denser phosphors (Figure 1). In this respect, high density x-ray phosphors such as Gd2O2S are better than ZnS based cathode ray tube phosphors. Scintillating fiber optics can be used instead of a discrete phosphor layer. The resolution of scintillating fiber optics that are used in x-ray imaging exceed 20 1p/mm and can be made very large. An example of a digital TEM image using a scintillating fiber optic plate is shown in Figure 2.

High-energy x-ray imaging spectrometer (HEXIS)

1998 ◽  
Author(s):  
James L. Matteson ◽  
Duane E. Gruber ◽  
William A. Heindl ◽  
Michael R. Pelling ◽  
Laurence E. Peterson ◽  
...  
Keyword(s):  
High Energy ◽  
Imaging Spectrometer ◽  
X Ray ◽  
X Ray Imaging

High-energy phase-contrast X-ray imaging using a two-crystal X-ray interferometer

2005 ◽  
Vol 12 (4) ◽  
pp. 534-536 ◽  
Author(s):  
Akio Yoneyama ◽  
Tohoru Takeda ◽  
Yoshinori Tsuchiya ◽  
Jin Wu ◽  
Thet-Thet Lwin ◽  
...  
Keyword(s):  
Phase Contrast ◽  
High Energy ◽  
X Ray ◽  
X Ray Imaging

Energy-dependent nebula extent and spatially resolved spectra of the pulsar wind nebula 3C 58

2020 ◽  
Vol 498 (2) ◽  
pp. 1911-1919
Author(s):  
Fang-Wu Lu ◽  
Quan-Gui Gao ◽  
Li Zhang
Keyword(s):  
Surface Brightness ◽  
Spectral Energy Distribution ◽  
High Energy ◽  
Spatial Variations ◽  
Spectral Energy ◽  
X Ray ◽  
Spatially Resolved ◽  
Photon Index ◽  
Pulsar Wind ◽  
Energy Dependent

ABSTRACT 3C 58 is a pulsar wind nebula (PWN) that shows an interesting energy-dependent nebula extent and spatial variations of the photon index and surface brightness in the X-ray band. These observations provide useful information with which to study the spatially dependent radiative cooling of electrons and the energy-dependent transport mechanisms within the nebula. In this paper, the energy-dependent nebula extent and spatially resolved spectra of this PWN are investigated in the framework of a spatially dependent particle transport model. The observations of the nebula, including the photon spectral energy distribution, spatial variations of the X-ray spectrum, and measurements of the nebula extent, can be naturally explained in this model. Our results show that the energy-dependent nebula extent favours an advection–diffusion scenario with advection-dominated transport, and the variations of the nebula extent with energy in the X-ray band can be attributed to the cooling losses of high-energy electrons affected by synchrotron burn-off. Particle diffusion plays an important role in modifying the spatial variations of the photon index and surface brightness in the X-ray band. The radial extents of the nebula at radio, GeV and TeV energies are predicted by the model, indicating that the nebula extent of 3C 58 varies with energy in these bands. The analyses show that the dependence of the adiabatic cooling rate and synchrotron radiation on the spectral index of injected particles is important for changing the nebula extent at different energies.

scholarly journals X-ray polarimetry – A new Window on Black Hole Systems

2016 ◽  
Vol 12 (S324) ◽  
pp. 338-341
Author(s):  
René W. Goosmann
Keyword(s):  
Black Hole ◽  
Binary Systems ◽  
Galactic Center ◽  
Galactic Nuclei ◽  
High Energy ◽  
X Ray ◽  
X Ray Imaging ◽  
History Of ◽  
Imaging Polarimetry ◽  
High Energy Emission

AbstractThree dedicated X-ray polarimetry mission projects are currently under phase A study at NASA and ESA. The need for this new observational window is more apparent than ever. On behalf of the consortium behind the X-ray Imaging Polarimetry Explorer (XIPE) we present here some prospects of X-ray polarimetry for our understanding of supermassive and stellar mass black hole systems. X-ray polarimetry is going to discriminate between leptonic and hadronic jet models in radio-loud active galactic nuclei. For leptonic jets it also puts important constraints on the origin of the seed photons that constitute the high energy emission via Comptonization. Another important application of X-ray polarimetry allows us to clarify the accretion history of the supermassive black hole at the Galactic Center. In a few Black Hole X-ray binary systems, X-ray polarimetry allows us to estimate in a new, independent way the angular momentum of the black hole.

scholarly journals High-energy, high-resolution x-ray imaging for metallic cultural heritages

AIP Advances ◽  
2017 ◽  
Vol 7 (10) ◽  
pp. 105122
Author(s):  
Masato Hoshino ◽  
Kentaro Uesugi ◽  
Ryuji Shikaku ◽  
Naoto Yagi
Keyword(s):  
High Resolution ◽  
High Energy ◽  
X Ray ◽  
X Ray Imaging

Development of Real Time High Energy X-Ray Imaging System for Use in Dynamic Fluoroscopy of Aero Gas Turbines

1975 ◽  
Author(s):  
A. E. Stewart
Keyword(s):  
Real Time ◽  
Gas Turbines ◽  
Imaging System ◽  
High Energy ◽  
Cesium Iodide ◽  
Imaging Systems ◽  
X Ray ◽  
X Ray Imaging ◽  
Different Types

This paper discusses the development of a real-time high energy x-ray imaging system for use in dynamic fluoroscopy of aero gas turbines. In order to cover the range of subjects on gas turbines, over ten combinations of film and screen types are used. Three different types of x-ray imaging systems were considered for use: direct type intensifiers (cesium iodide phosphors), and indirect type intensifiers — Marconi “Marionette” and the Oude Delft “Delcalix.”

Sign in / Sign up

Export Citation Format

Share Document