NCRP Commentary No. 20: Radiation Protection and Measurement Issues Related to Cargo Scanning with Accelerator-Produced High-Energy X-Rays

Harmful effects of radiation and call for protection against it were recognized practically immidiatly upon the discovery of X-rays and radioactivity. A chronological review of some key events in development of radiation protection is given in this paper. First, the main activities of the ICRP since its establishment to nowadays are presented. Afterwards, a general description of some, according to the author's opinion, important events in the field of radiation protection in the former Yugoslavia and Serbia and Montenegro are given as: Vinca accident; Organization of Radiation Protection Laboratory in Vinca Institute; International Vinca Dosimetry Experiment; First Symposium and organization of the Yugoslav Radiation Protection Association; the French - Yugoslav Colloquium on radiation protection; International intercomparison experiment on nuclear accident dosimetry, and the International Summer Schools and Symposium on Radiation Protection organized in Yugoslavia. Some comments on the Three Mile Island and Chernobyl accidents are given as well. Bioindicators of low dose and dose intensity exposure are cited as one of the main problems that have to be resolved in radiation protection in the near future. Finally, as one of the main problems that, according to the author's opinion, physicists have to resolve in this field in the near future would be development of the operational dosimeter for high energy neutrons.

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The Basic Physical Principles of Ion, Electron, and X-Ray Detectors and Their Application to Microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117777 ◽

1985 ◽

Vol 43 ◽

pp. 154-157

Author(s):

A.J. Tousimis

Keyword(s):

Ion Beam ◽

Depth Resolution ◽

Sample Surface ◽

High Energy ◽

X Rays ◽

X Ray ◽

Electrons And Ions ◽

Spatial Depth ◽

Minimum Surface Area ◽

Physical Principles

An integral and of prime importance of any microtopography and microanalysis instrument system is its electron, x-ray and ion detector(s). The resolution and sensitivity of the electron microscope (TEM, SEM, STEM) and microanalyzers (SIMS and electron probe x-ray microanalyzers) are closely related to those of the sensing and recording devices incorporated with them.Table I lists characteristic sensitivities, minimum surface area and depth analyzed by various methods. Smaller ion, electron and x-ray beam diameters than those listed, are possible with currently available electromagnetic or electrostatic columns. Therefore, improvements in sensitivity and spatial/depth resolution of microanalysis will follow that of the detectors. In most of these methods, the sample surface is subjected to a stationary, line or raster scanning photon, electron or ion beam. The resultant radiation: photons (low energy) or high energy (x-rays), electrons and ions are detected and analyzed.

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MINIMIZING THE EXPOSURE TO THE EYE LENS OF RADIOLOGIC TECHNOLOGISTS ASSISTING PATIENTS DURING CHEST X RAYS: A PHANTOM STUDY

Radiation Protection Dosimetry ◽

10.1093/rpd/ncab019 ◽

2021 ◽

Vol 193 (1) ◽

pp. 43-54

Author(s):

Yasuda Mitsuyoshi ◽

Funada Tomoya ◽

Sato Hisaya ◽

Kato Kyoichi

Keyword(s):

Radiation Protection ◽

Phantom Study ◽

International Commission ◽

Eye Lens ◽

Radiological Protection ◽

X Rays ◽

Radiologic Technologists ◽

Maximum Reduction ◽

The Right

Abstract As chest x rays involve risks of patients falling, radiologic technologists (technologists) commonly assist patients, and as the assistance takes place near the patients, the eye lenses of the technologists are exposed to radiation. The recommendations of the International Commission on Radiological Protection suggest that the risk of developing cataracts due to lens exposure is high, and this makes it necessary to reduce and minimize the exposure. The present study investigated the positions of technologists assisting patients that will minimize exposure of the eye lens to radiation. The results showed that it is possible to reduce the exposure by assisting from the following positions: 50% at the sides rather than diagonally behind, 10% at the right side of the patient rather than the left and 40% at 250 mm away from the patient. The maximum reduction with radiation protection glasses was 54% with 0.07 mmPb and 72% with 0.88 mmPb.

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“Cartography” in 7-Dimensions at CHESS: Mapping of Structure in Real Space, Reciprocal Space, and Time Using High-Energy X-rays

Synchrotron Radiation News ◽

10.1080/08940886.2020.1841491 ◽

2020 ◽

Vol 33 (6) ◽

pp. 11-16

Author(s):

K. E. Nygren, ◽

D. C. Pagan, ◽

J. P. C. Ruff ◽

E. Arenholz ◽

J. D. Brock

Keyword(s):

High Energy ◽

Real Space ◽

Reciprocal Space ◽

X Rays ◽

Space And Time

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The interstellar medium in young supernova remnants: key to the production of cosmic X-rays and $\gamma $-rays

Astrophysics and Space Science ◽

10.1007/s10509-021-03960-4 ◽

2021 ◽

Vol 366 (6) ◽

Author(s):

Hidetoshi Sano ◽

Yasuo Fukui

Keyword(s):

Interstellar Medium ◽

Supernova Remnants ◽

Cosmic Ray ◽

High Energy ◽

X Rays ◽

Interstellar Gas ◽

High Energy Radiation ◽

Dense Cores ◽

The Relationship ◽

Turbulent Velocity Field

AbstractWe review recent progress in elucidating the relationship between high-energy radiation and the interstellar medium (ISM) in young supernova remnants (SNRs) with ages of ∼2000 yr, focusing in particular on RX J1713.7−3946 and RCW 86. Both SNRs emit strong nonthermal X-rays and TeV $\gamma $ γ -rays, and they contain clumpy distributions of interstellar gas that includes both atomic and molecular hydrogen. We find that shock–cloud interactions provide a viable explanation for the spatial correlation between the X-rays and ISM. In these interactions, the supernova shocks hit the typically pc-scale dense cores, generating a highly turbulent velocity field that amplifies the magnetic field up to 0.1–1 mG. This amplification leads to enhanced nonthermal synchrotron emission around the clumps, whereas the cosmic-ray electrons do not penetrate the clumps. Accordingly, the nonthermal X-rays exhibit a spatial distribution similar to that of the ISM on the pc scale, while they are anticorrelated at sub-pc scales. These results predict that hadronic $\gamma $ γ -rays can be emitted from the dense cores, resulting in a spatial correspondence between the $\gamma $ γ -rays and the ISM. The current pc-scale resolution of $\gamma $ γ -ray observations is too low to resolve this correspondence. Future $\gamma $ γ -ray observations with the Cherenkov Telescope Array will be able to resolve the sub-pc-scale $\gamma $ γ -ray distribution and provide clues to the origin of these cosmic $\gamma $ γ -rays.

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Introducing the HD+B model for pulsar wind nebulae: a hybrid hydrodynamics/radiative approach

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1052 ◽

2020 ◽

Vol 494 (3) ◽

pp. 4357-4370

Author(s):

B Olmi ◽

D F Torres

Keyword(s):

Gamma Ray ◽

High Energy ◽

Theoretical Modelling ◽

X Rays ◽

Pulsar Wind Nebulae ◽

New Approach ◽

Energy Gamma ◽

Radiative Model ◽

Pulsar Wind

ABSTRACT Identification and characterization of a rapidly increasing number of pulsar wind nebulae is, and will continue to be, a challenge of high-energy gamma-ray astrophysics. Given that such systems constitute -by far- the most numerous expected population in the TeV regime, such characterization is important not only to learn about the sources per se from an individual and population perspective, but also to be able to connect them with observations at other frequencies, especially in radio and X-rays. Also, we need to remove the emission from nebulae in highly confused regions of the sky for revealing other underlying emitters. In this paper, we present a new approach for theoretical modelling of pulsar wind nebulae: a hybrid hydrodynamic-radiative model able to reproduce morphological features and spectra of the sources, with relatively limited numerical cost.

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Ex-SituStress Measurements in Polycrystalline Ceramics Using Photo-Stimulated Luminescence Spectroscopy and High-Energy X-Rays

Journal of the American Ceramic Society ◽

10.1111/j.1551-2916.2009.03063.x ◽

2009 ◽

Vol 92 (7) ◽

pp. 1567-1573 ◽

Cited By ~ 8

Author(s):

Seetha Raghavan ◽

Peter K. Imbrie

Keyword(s):

High Energy ◽

Luminescence Spectroscopy ◽

X Rays ◽

Polycrystalline Ceramics

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Detector commissioning and development for PETRA-III

Diamond Light Source Proceedings ◽

10.1017/s2044820110000043 ◽

2010 ◽

Vol 1 (SRMS-7) ◽

Cited By ~ 1

Author(s):

David Pennicard ◽

Heinz Graafsma ◽

Michael Lohmann

Keyword(s):

High Speed ◽

Materials Science ◽

Dynamic Range ◽

Photon Counting ◽

High Energy ◽

X Rays ◽

Silicon Detectors ◽

Time Resolved ◽

Wide Range ◽

Synchrotron Light

The new synchrotron light source PETRA-III produced its first beam last year. The extremely high brilliance of PETRA-III and the large energy range of many of its beamlines make it useful for a wide range of experiments, particularly in materials science. The detectors at PETRA-III will need to meet several requirements, such as operation across a wide dynamic range, high-speed readout and good quantum efficiency even at high photon energies. PETRA-III beamlines with lower photon energies will typically be equipped with photon-counting silicon detectors for two-dimensional detection and silicon drift detectors for spectroscopy and higher-energy beamlines will use scintillators coupled to cameras or photomultiplier tubes. Longer-term developments include ‘high-Z’ semiconductors for detecting high-energy X-rays, photon-counting readout chips with smaller pixels and higher frame rates and pixellated avalanche photodiodes for time-resolved experiments.

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