X rays in Atomic and Nuclear Physics

Physics Today ◽  
1974 ◽  
Vol 27 (7) ◽  
pp. 47-48
Author(s):  
N. A. Dyson ◽  
Winthrop W. Smith
Keyword(s):  
Nuclear Physics ◽  
X Rays

1. The fly in the cathedral

2015 ◽  
Author(s):  
Frank Close
Keyword(s):  
Internal Structure ◽  
Nuclear Physics ◽  
Positive Charge ◽  
X Rays ◽  
Ernest Rutherford ◽  
Nuclear Atom ◽  
Positively Charged

‘The fly in the cathedral’ charts the discovery of the nuclear atom and the start of modern atomic and nuclear physics. It began in 1895 with the discovery of X-rays by Wilhelm Roentgen and radioactivity by Henri Becquerel. In 1897, J.J. Thomson discovered the electron and realised they were common to all atoms, which implied that atoms have an internal structure. Negatively-charged electrons are bound to positively-charged entities within the atom, but what carries this positive charge and how is it distributed? It was Ernest Rutherford, in 1911, who announced his solution: all of an atom’s positive charge and most of its mass are contained in a compact nucleus at the centre.

scholarly journals 3D Isotope Density Measurements by Energy-Resolved Neutron Imaging

2021 ◽  
Author(s):  
Adrian Simon Losko ◽  
Sven Vogel
Keyword(s):  
Cross Sections ◽  
Nuclear Physics ◽  
Tomographic Reconstruction ◽  
Three Dimensional ◽  
Neutron Imaging ◽  
X Rays ◽  
Neutron Transmission ◽  
Quantitative Measurements ◽  
Transmission Detector ◽  
Elemental Characterization

Abstract Tools for three-dimensional elemental characterization are available on length scales ranging from individual atoms, using electrons as a probe, to micrometers with X-rays. However, for larger volumes up to millimeters or centimeters, quantitative measurements of elemental or isotope densities were hitherto only possible on the surface. Here, a novel quantitative elemental characterization method based on energy-resolved neutron imaging, utilizing the known neutron absorption cross sections with their ‘finger-print’ absorption resonance signatures, is demonstrated. Enabled by a pixilated time-of-flight neutron transmission detector installed at an intense short-pulsed spallation neutron source, for this demonstration 3.25 million state-of-the-art nuclear physics neutron transmission analyses were conducted to derive isotopic densities for five isotopes in 3D in a volume of 0.25 cm3. The tomographic reconstruction of the isotope densities provides elemental maps similar to X-ray microprobe maps for any cross-section in the probed volume. The bulk isotopic density of a U-20Pu-10Zr-3Np-2Am nuclear transmutation fuel sample was measured, agrees well with mass-spectrometry and is evidence of the accuracy of the method.

scholarly journals Semi-Analytical Monte Carlo Method to Simulate the Signal of the VIP-2 Experiment

Symmetry ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 6
Author(s):  
Edoardo Milotti ◽  
Sergio Bartalucci ◽  
Sergio Bertolucci ◽  
Massimiliano Bazzi ◽  
Mario Bragadireanu ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Nuclear Physics ◽  
Current Source ◽  
Detection Sensitivity ◽  
Modulation Scheme ◽  
X Rays ◽  
Monte Carlo Program ◽  
Starting Point ◽  
Potential Improvement ◽  
A Current

The VIP-2 collaboration runs an apparatus in the Gran Sasso underground laboratories of the Italian Institute for Nuclear Physics (INFN) designed to search for anomalous X-rays from electron-atom interactions due to violations of the fundamental antisymmetry of multi-electron wavefunctions. The experiment implements the scheme first proposed by Ramberg and Snow, where a current source injects electrons into a metal strip (the experiment’s target). In this paper we describe the structure of a Monte Carlo program to simulate a new upgrade of the experiment, where the anomalous X-ray emission is modulated by an arbitrary time-varying input current. A novel feature of the simulation algorithm is that the Monte Carlo program is based on a mixture of analytical and numerical methods. We report preliminary, exploratory results on the expected detection rate for different modulations of the injected current; these results are a starting point on the way to optimize the modulation scheme and indicate a large potential improvement of the detection sensitivity.

X Rays in Atomic and Nuclear Physics

1974 ◽  
Vol 25 (6) ◽  
pp. 240-240
Author(s):  
E J Burge
Keyword(s):  
Nuclear Physics ◽  
X Rays

scholarly journals CIEDs (cardiac implantable electronic devices) error due to neutrons from X-ray therapy equipment

Impact ◽  
2021 ◽  
Vol 2021 (5) ◽  
pp. 31-33
Author(s):  
Hiroaki Matsubara ◽  
Hiroaki Matsubara
Keyword(s):  
Nuclear Physics ◽  
Interdisciplinary Collaboration ◽  
Electronic Devices ◽  
Assistant Professor ◽  
X Rays ◽  
Theoretical Understanding ◽  
Cardiac Implantable Electronic Devices ◽  
Cardiac Devices ◽  
The Right ◽  
Key Techniques

Interdisciplinary collaboration is necessary for the advancement of medicine. A lack of collaboration can lead to misconceptions and a lack of theoretical understanding, which can affect the care afforded to patients. With the right collaborations between scientists in fields outside of medicine, misconceptions can be corrected and understanding improved. Assistant Professor Hiroaki Matsubara, Tokyo Women's Medical University, Japan, is a nuclear physicist who is applying his skills and expertise to advance the field of medicine. Nuclear physics is used in several key techniques and tools in medicine such as X-rays and radiotherapy. Matsubara is interested in the issues that can arise in patients with implanted cardiac devices that require radiotherapy. The radiation from radiotherapy can affect the proper functioning of cardiac implantable electronic devices (CIEDs), leading to dangerous malfunctions, even when the tumour being targeted is far from the heart. From gathering data from clinical settings and running tests in non-clinical environments Matsubara found that there was no correlation between photon exposure levels and device malfunction, which suggested another source of malfunction arising after radiotherapy. Using his nuclear expertise, he was able to uncover the source of CIED malfunction following radiotherapy.

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.

scholarly journals Detectors and Cultural Heritage: The INFN-CHNet Experience

2021 ◽  
Vol 11 (8) ◽  
pp. 3462
Author(s):  
Lorenzo Giuntini ◽  
Lisa Castelli ◽  
Mirko Massi ◽  
Mariaelena Fedi ◽  
Caroline Czelusniak ◽  
...  
Keyword(s):  
Cultural Heritage ◽  
Gamma Rays ◽  
Nuclear Physics ◽  
State Of The Art ◽  
X Rays ◽  
X Ray ◽  
Scientific Approach ◽  
Absorbed Power ◽  
New Instrumentation ◽  
Italian National Institute

Detectors are a key feature of the contemporary scientific approach to cultural heritage (CH), both for diagnostics and conservation. INFN-CHNet is the network of the Italian National Institute of Nuclear Physics that develops and applies new instrumentation for the study of CH. This process results in both optimized traditional state-of-the-art and highly innovative detection setups for spectrometric techniques. Examples of the former are X-rays, gamma-rays, visible-light and particles spectrometers tailored for CH applications, with optimized performances, reliability, weight, transportability, cost, absorbed power, and complementarity with other techniques. Regarding the latter, examples are ARDESIA, the array of detectors at the DAΦNE-Light facility, the MAXRS detection setup at the Riken-RAL muon beamline and the imaging facilities at the LENA Laboratory. Paths for next-generation instruments have been suggested, as in the case of the X-ray Superconductive Detectors and X-ray Microcalorimeter Spectrometers, allowing astonishing improvement in energy resolution. Many issues in CH can now be addressed thanks to scientific techniques exploiting the existing detectors, while many others are still to be addressed and require the development of new approaches and detectors.

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