scholarly journals Requirement of HE-PIXE at High Z Elements in Charnockite Matrix Composition

2020 ◽  
Author(s):  
Avupati Venkata Surya Satyanarayana ◽  
Mokka Jagannadha Rao ◽  
Byreddy Seetharami Reddy
Keyword(s):  
Gamma Rays ◽  
Analytical Techniques ◽  
High Energy ◽  
Low Energy ◽  
Matrix Composition ◽  
X Rays ◽  
X Ray ◽  
Analytical Technique ◽  
Analytical Tools ◽  
Ray Series

Abstract. The maximum of Proton Induced X-ray Emission analytical technique on metamorphic rocks in geology has used 3 MeV range proton beams for excitation of thick targets. Protons of such energies do not accurately excite K-X–rays for high Z elements in matrix geological compositions like charnockite. In this analysis, low-energy PIXE (LE-PIXE) uses K-X-rays of Low Z elements and L-X-ray series for high Z elements. The resulting spectra between K-X-rays of light elements and L-X-rays of heavy elements can require striping techniques to resolve overlap difficulties in matrix composition. The results high Z elements in charnockite are to be expected, as the cross section for K-shell ionization of high-Z elements have greater values in the proton energy range of greater than 3 MeV in case of charnockite matrix composition. It has been suggested that the overlap of these discrete, gamma-rays with the X-ray spectrum may be serious problem in charnockite high energy PIXE (HE-PIXE) work, sufficient to preclude its use as a viable analytical technique. The conclusion proves that for a very complex matrix charnockite material of unknown chemistry, a HE-PIXE analytical spectrum may contain various X-ray and gamma peaks, some of which may overlap, making the analysis of line identities and the evaluation of X-ray counts intractable. It does not however represent any intrinsic drawback in HE-PIXE, nor does it mean that HE-PIXE is any more or less intractable than many other nuclear analytical techniques. Alternatively, the same analytical tool use could be made of gamma-rays in HE-PIXE as in low energy analytical tools like PIGE, NRA or INAA to obtain the results of charnockite at high Z completely.

scholarly journals Centaurus A at Hard X-Rays and Soft Gamma-Rays

2010 ◽  
Vol 27 (4) ◽  
pp. 431-438 ◽  
Author(s):  
H. Steinle
Keyword(s):  
Energy Range ◽  
Spatial Resolution ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Spectral Energy Distribution ◽  
High Energy ◽  
Spectral Energy ◽  
X Rays ◽  
Satellite Mission ◽  
X Ray

AbstractCen A, at a distance of less than 4 Mpc, is the nearest radio-loud AGN. Its emission is detected from radio to very-high energy gamma-rays. Despite the fact that Cen A is one of the best studied extragalactic objects the origin of its hard X-ray and soft gamma-ray emission (100 keV <E< 50 MeV) is still uncertain. Observations with high spatial resolution in the adjacent soft X-ray and hard gamma-ray regimes suggest that several distinct components such as a Seyfert-like nucleus, relativistic jets, and even luminous X-ray binaries within Cen A may contribute to the total emission in the MeV regime that has been detected with low spatial resolution. As the Spectral Energy Distribution of Cen A has its second maximum around 1 MeV, this energy range plays an important role in modeling the emission of (this) AGN. As there will be no satellite mission in the near future that will cover this energies with higher spatial resolution and better sensitivity, an overview of all existing hard X-ray and soft gamma-ray measurements of Cen A is presented here defining the present knowledge on Cen A in the MeV energy range.

scholarly journals Improving EDS For Low Energy X-Rays Under 1000eV Using an Attachable Detector Optic

2008 ◽  
Vol 16 (2) ◽  
pp. 6-9
Author(s):  
David O’Hara ◽  
Greg Brown ◽  
Eric Lochner
Keyword(s):  
Dead Time ◽  
Beam Current ◽  
High Energy ◽  
Low Energy ◽  
Detector Response ◽  
X Rays ◽  
Ray Optics ◽  
X Ray ◽  
Optics Fabrication ◽  
Made In

Although considerable advances have been made in Energy Dispersive Detectors for microanalysis, low energy analysis under 1000eV is still relatively poor due to detector response and inefficient production of low energy x-rays. X-ray optics fabrication methods by O’Hara and measurements by McCarthy et. al. indicated that it should be possible to fabricate x-ray optics that could be used to significantly increase the low energy x-ray flux seen by an EDS detector without increasing the beam current. Such an optic would be useful to increase low energy counts without moving the detector closer, which would simply increase the high energy counts and dead time.

scholarly journals Hot Accretion Disks and the High Energy Background

1983 ◽  
Vol 104 ◽  
pp. 345-346
Author(s):  
M. Kafatos ◽  
Jean A. Eilek
Keyword(s):  
Active Galactic Nuclei ◽  
Accretion Disks ◽  
Spectral Range ◽  
Gamma Rays ◽  
Gamma Ray ◽  
Galactic Nuclei ◽  
Seyfert Galaxies ◽  
High Energy ◽  
X Rays ◽  
X Ray

The origin of the high energy (X-ray and gamma-ray) background may be attributed to discrete sources, which are usually thought to be active galactic nuclei (AGN) (cf. Rothschild et al. 1982, Bignami et al. 1979). At X-rays a lot of information has been obtained with HEAO-1 in the spectral range 2–165 keV. At gamma-rays the background has been estimated from the Apollo 15 and 16 (Trombka et al. 1977) and SAS-2 (Bignami et al. 1979) observations. A summary of some of the observations (Rothschild et al. 1982) is shown in Figure 1. The contribution of AGN to the diffuse high energy background is uncertain at X-rays although it is generally estimated to be in the 20–30% range (Rothschild et al. 1982). At gamma-rays, in the range 1–150 MeV, AGN (specifically Seyfert galaxies) could account for all the emission.

KAONIC HELIUM MEASUREMENTS IN THE SIDDHARTA EXPERIMENT

2011 ◽  
Vol 26 (03n04) ◽  
pp. 601-603
Author(s):  
◽  
D. L. SIRGHI ◽  
M. BAZZI ◽  
G. BEER ◽  
L. BOMBELLI ◽  
...  
Keyword(s):  
Energy Shift ◽  
High Energy ◽  
Low Energy ◽  
Kaonic Hydrogen ◽  
X Rays ◽  
X Ray ◽  
Kaonic Deuterium ◽  
Theoretical Predictions ◽  
First Time ◽  
Hadronic Atom

The SIDDHARTA experiment (SIlicon Drift Detector for Hadronic Atom Research by Timing Application) had the aim to perform kaonic atoms X-ray transitions measurements, to better understand aspects of the low-energy QCD in the strangeness sector. The experiment combined the excellent low-energy kaon beam generated at DAΦNE, allowing to use gaseous targets, with excellent fast X-rays detectors: Silicon Drift Detectors. SIDDHARTA was installed on DAΦNE in autumn 2008 and took data till late 2009. Apart of the kaonic hydrogen and kaonic deuterium measurements, we have performed the kaonic helium transitions to the 2p level ( L -lines) measurements: for the first time in a gaseous target for helium4 and for the first time ever for kaonic helium3. The interest for such type of measurement was rather high, being it triggered by two reasons: the so-called "kaonic helium puzzle" (even if this was solved by KEK-PS E570 experiment, but a cross-check was useful) and some theoretical predictions of possible high energy shift (at the level of 10 eV). In this paper the preliminary results for the measurements to the 2p level ( L -series) for kaonic helium4 and kaonic helium3 are presented.

HIGH ENERGY PROTON PIXE [HEPP]

1993 ◽  
Vol 03 (03) ◽  
pp. 187-214 ◽  
Author(s):  
J.S.C. McKEE
Keyword(s):  
Review Paper ◽  
Analytical Techniques ◽  
High Energy ◽  
Low Energy ◽  
X Ray ◽  
Energy Proton ◽  
History Of ◽  
History Of Analysis ◽  
Compare And Contrast ◽  
Mev Protons

Studies of particle induced X-ray emission (PIXE) have been widespread and detailed in recent years and despite the fact that most data obtained are from low energy 1–3 MeV experiments, the value of higher energy proton work with its emphasis on K X-ray emission has become more marked as time has progressed. The purpose of this review paper is to outline the history of analysis using high energy protons and to compare and contrast the results obtained with those from lower energy analysis using more firmly established analytical techniques. The work described will concentrate exclusively on proton induced processes and will attempt to outline the rationale for selecting an energy, greater than 20 and up to 70 MeV protons for initiating particles. The relative ease and accuracy of the measurements obtained will be addressed. Clearly such X-ray studies should be seen as complementing low energy work in many instances rather than competing directly with them. However, it will be demonstrated that above a Z value of approximately 20, K X-ray analysis using high energy protons is the only way to go in this type of analysis.

scholarly journals Low Z Elements of High Grade Metamorphic Rocks by PIXE Analysis – A Comprehensive Review

2020 ◽  
Author(s):  
Avupati Venkata Surya Satyanarayana ◽  
Mokka Jagannadha Rao ◽  
Byreddy Seetharami Reddy
Keyword(s):  
Cross Section ◽  
Analytical Techniques ◽  
Thick Target ◽  
Light Energy ◽  
Low Energy ◽  
High Grade ◽  
X Rays ◽  
Pixe Analysis ◽  
X Ray ◽  
Line Intensities

Abstract. The majority of PIXE analytical study on geosciences has used 3 MeV proton beams for excitation and these studies generally uses the K-X-rays for low Z elements and L-X-rays for high Z elements. The present study of resulting spectra of metamorphic high grade rocks like charnockite can require striping techniques to resolve interference problems between low and high Z elements on the applications of light energy-PIXE using Si (Li) detector. In all forms of X-ray analysis, including thick-target light energy-PIXE, the X-ray signal is a dependent of the ionization cross section and for low-energy protons, the cross section is high for the K shells of light elements and the L shells of heavy elements in charnockite rock providing sufficient fluorescent yield for analytical purposes. For Z > 55, 3 MeV protons cannot ionize K-shell electrons and analysis depends on the use of L-X-ray lines in charnockite rock. Such L-X-ray spectra are complicated and can be affected by interferences K-X-rays from low Z elements. The low Z elements present in the charnockite were identified by previous complementary analytical techniques, but not identified in this study due to the above PIXE experiment limitations, and also particularly due to the dimensions of Si (Li) detector because of low energy K-X-rays of the elements absorbed by the detector window. Both interferences complexity and detector efficiency can lead to difficulties and ambiguity in the interpretation of spectra of low Z charnockite composition, a problem that is exacerbated by uncertainty in relative K-X-ray line intensities of low Z elements. From this investigation, the light energy-PIXE is ideal for the analysis of low Z 

Practical X-ray Spectrometry with Second-Generation Microcalorimeter Detectors

2012 ◽  
Vol 20 (4) ◽  
pp. 38-42 ◽  
Author(s):  
Robin Cantor ◽  
Hideo Naito
Keyword(s):  
Electron Microscope ◽  
Spatial Resolution ◽  
Energy Resolution ◽  
Semiconductor Industry ◽  
High Energy ◽  
High Energy Resolution ◽  
X Rays ◽  
X Ray ◽  
Analytical Technique ◽  
Transmission Electron

X-ray spectroscopy is a widely used and extremely sensitive analytical technique for qualitative as well as quantitative elemental analysis. Typically, high-energy-resolution X-ray spectrometers are integrated with a high-spatial-resolution scanning electron microscope (SEM) or transmission electron microscope (TEM) for X-ray microanalysis applications. The focused electron beam of the SEM or TEM excites characteristic X rays that are emitted by the sample. The integrated X-ray spectrometer can then be used to identify and quantify the elemental composition of the sample on a sub-micron length scale. This combination of energy resolution and spatial resolution makes X-ray microanalysis of great importance to the semiconductor industry.

Burns by Ionizing and Non-Ionizing Radiation

2020 ◽  
Author(s):  
Giovanni Alcocer ◽  
Priscilla Alcocer ◽  
Carlos Marquez
Keyword(s):  
Ionizing Radiation ◽  
Visible Light ◽  
Gamma Rays ◽  
Biological Effects ◽  
High Energy ◽  
Low Energy ◽  
X Rays ◽  
Nuclear Accidents ◽  
Diagnostic Equipment ◽  
Nonionizing Radiation

Abstract This article consists of the study and investigative analysis of the effects of burns by radiation in humans. Cases of nuclear accidents, such as Chernobyl (ionizing radiation) and the effects of non-ionizing radiation such as infrared and microwave radiation are detailed. It is examined cases of injuries and burns by ionizing radiation due to irradiation (diagnostic equipment and medical treatment: X-rays, radiotherapy) or contamination (nuclear accidents, wars). Injuries and burns are also caused by nonionizing radiation, such as visible light (laser), ultraviolet, radiofrequency. There are numerous biological issues in the case of tissues, the ionizing radiation (ionizing particles and electromagnetic radiation: X-rays, gamma rays and high energy ultraviolet) can cause damage mainly in the DNA. This can cause mutations in its genetic code and cancer 5. In addition, damage to other tissues and organs can occur, as well as burns, erythema and lesions. The biological effects of nonionizing radiation are currently under investigation. Burns, erythema and lesions can also occur due to the following types of radiation: low energy ultraviolet, visible light, infrared, microwave, radiofrequency, electromagnetic fields. The purpose of this article is to provide an exhaustive analysis of all types of both ionizing and non-ionizing radiation and their effects on living beings. Finally, it is important to follow all safety and radiation protections against both ionizing and non-ionizing radiation.

Tsinghua Center for Astrophysics and the Dark Universe

2014 ◽  
Vol 03 (02) ◽  
pp. 63-70
Author(s):  
Charling Tao
Keyword(s):  
Gamma Rays ◽  
Nuclear Physics ◽  
Gamma Ray ◽  
High Energy ◽  
X Rays ◽  
High Energy Astrophysics ◽  
Research Directions ◽  
X Ray ◽  
Main Research ◽  
Optical Wavelengths

The Tsinghua Center for Astrophysics (THCA) was founded in 2001 by Prof. Li Tipei and Shang Rencheng. A distinguishing characteristic of THCA's astrophysics program is its emphasis on space X-ray and gamma-ray instrumentation, by taking advantage of Tsinghua's strong programs on nuclear physics, nuclear engineering, space and aeronautics engineering, as well as electronics and information technology. The main research directions in THCA include high energy astrophysics and cosmology with space and ground observations in X-rays and gamma-rays, and more recently in optical wavelengths, radio-astronomy, gravitational waves, dark matter and dark energy analyses and projects.

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