scholarly journals Comparison of traditional and synchrotron beam methodologies in Mössbauer experiments in a rotating system

2021 ◽  
Vol 28 (1) ◽  
pp. 78-85
Author(s):  
A. L. Kholmetskii ◽  
T. Yarman ◽  
O. Yarman ◽  
M. Arik
Keyword(s):  
Performance Improvement ◽  
Energy Shift ◽  
Practical Significance ◽  
Rotating System ◽  
Synchrotron Source ◽  
Compact Source ◽  
Laboratory Setup ◽  
Synchrotron Beam ◽  
Crucial Information ◽  
Resonant Radiation

Recent Mössbauer experiments in a rotating system reported by others in the literature have involved the application of synchrotron radiation onto a spinning semi-circular resonant absorber. Here, the physical interpretation of these methodologies, and their alleged performance improvement, is analyzed in the light of our own team's past experience based instead on the traditional laboratory setup. It is shown that a number of fundamental shortcomings in the approach reported in the literature deprives it of any practical significance with respect to the improvement of the technique of Mössbauer rotor experiments with a synchrotron source. It is concluded that, at present, only Mössbauer experiments relying on an ordinary compact source of resonant radiation and a resonant absorber both fixed on the rotor promise to provide crucial information with respect to the physical origin of the observed energy shift between emitted and absorbed resonant radiation in a rotating system.

First results from the XMCD facility at the Energy-Dispersive EXAFS beamline of the Indus-2 synchrotron source

2019 ◽  
Vol 26 (2) ◽  
pp. 445-449
Author(s):  
N. Patra ◽  
U. G. P. S. Sachan ◽  
S. SundarRajan ◽  
Sanjay Malhotra ◽  
Vijay Harad ◽  
...  
Keyword(s):  
Magnetic Circular Dichroism ◽  
Energy Dispersive ◽  
X Rays ◽  
Beam Direction ◽  
Synchrotron Source ◽  
X Ray ◽  
Synchrotron Beam ◽  
First Results ◽  
Set Up ◽  
Good Agreement

Setting up of the X-ray Magnetic Circular Dichroism (XMCD) measurement facility with hard X-rays at the Energy-Dispersive EXAFS beamline (BL-08) at the Indus-2 synchrotron source is reported. This includes the design and development of a water-cooled electromagnet having a highest magnetic field of 2 T in a good field volume of 125 mm3 and having a 10 mm hole throughout for passage of the synchrotron beam. This also includes the development of an (X–Z–θ) motion stage for the heavy electromagnet for aligning its axis and the beam hole along the synchrotron beam direction. Along with the above developments, also reported is the first XMCD signal measured on a thick Gd film in the above set-up which shows good agreement with the reported results. This is the first facility to carry out XMCD measurement with hard X-rays in India.

The Huber G670 imaging-plate Guinier camera tested on beamline I711 at the MAX II synchrotron

2000 ◽  
Vol 33 (2) ◽  
pp. 394-396 ◽  
Author(s):  
Kenny Ståhl
Keyword(s):  
Angular Resolution ◽  
High Angular Resolution ◽  
Imaging Plate ◽  
Correction Factors ◽  
Synchrotron Source ◽  
X Ray ◽  
Synchrotron Beam ◽  
Unusual Combination ◽  
Low Symmetry ◽  
Collection Time

A Huber G670 imaging-plate Guinier powder diffraction camera has been tested at an X-ray synchrotron source. It was found to be a very potent tool, offering an unusual combination of high angular resolution and short data collection time, while using very small amounts of sample. Specifically, it was found that: (i) the angular resolution (full width at half-maximum) varies between 0.07 and 0.15° in 2θ without focusing,i.e.relying on a parallel synchrotron beam; (ii) with a readout and erasure cycle time of 15 s, it is possible to obtain Rietveld-refinable data within less than a minute for a low-symmetry zeolite refined with 82 parameters; (iii) special attention has to be given to calibration of the detector and some general geometrical correction factors should be included in the data reduction.

scholarly journals Mössbauer experiments in a rotating system and physical interpretation of their results

2021 ◽  
pp. 34-43
Author(s):  
Alexander L. Kholmetskii ◽  
Tolga Yarman ◽  
Ozan Yarman ◽  
Metin Arik
Keyword(s):  
Energy Shift ◽  
Special Theory ◽  
Relativistic Energy ◽  
Theory Of Relativity ◽  
Rotating System ◽  
Rotating Systems ◽  
Extra Energy ◽  
Quantum Mechanical Description ◽  
Dilation Effect ◽  
The Moment

We discuss the results of modern Mössbauer experiments in a rotating system, which show the presence of an extra energy shift between the emitted and absorbed resonant radiation in addition to the relativistic energy shift of the resonant lines due to the time dilation effect in the co-rotating source and absorber with different radial coordinates. We analyse the available attempts to explain the origin of the extra energy shift, which include some extensions of special theory of relativity with hypothesis about the existence of limited acceleration in nature, with hypothesis about a so-called «time-dependent Doppler effect», as well as in the framework of the general theory of relativity under re-analysis of the metric effects in the rotating system, which is focused to the problem of correct synchronisation of clocks in a rotating system with a laboratory clock. We show that all such attempts remain unsuccessful until the moment, and we indicate possible ways of solving this problem, which should combine metric effects in rotating systems with quantum mechanical description of resonant nuclei confined in crystal cells.

A powder diffractometer for a synchrotron source

1987 ◽  
Vol 20 (3) ◽  
pp. 173-178 ◽  
Author(s):  
T. M. Sabine
Keyword(s):  
Particle Size ◽  
Data Collection ◽  
The Other ◽  
Bragg Angle ◽  
Synchrotron Source ◽  
Synchrotron Beam ◽  
Powder Diffractometer ◽  
Vertical Divergence ◽  
Spread Parameters ◽  
Recent Experimental Work

A design is given for a powder diffractometer on a synchrotron source. A reasonable balance between resolution and luminosity is achieved by making the effective mosaic spread parameters of the monochromator and analyser crystal equal to the vertical divergence of the synchrotron beam. A monochromator with a Bragg angle of 60° should be used. Care is necessary in preparing specimens for data collection to avoid the hazards of particle-size broadening on one hand and extinction on the other. The conclusions are compared with recent experimental work.

Einstein’s “Clock Hypothesis” and Mössbauer Experiments in a Rotating System

2019 ◽  
Vol 74 (2) ◽  
pp. 91-100
Author(s):  
Alexander Kholmetskii ◽  
Tolga Yarman ◽  
Ozan Yarman ◽  
Metin Arik
Keyword(s):  
Energy Shift ◽  
Relativity Theory ◽  
Theory Of Relativity ◽  
Rotating Disc ◽  
Rotating System ◽  
Rotating Systems ◽  
Extra Energy ◽  
Rotor Experiment ◽  
Clock Hypothesis ◽  
The Moment

AbstractAn extra energy shift between emitted and received radiation on a rotating disc – next to the conventionally recognised second-order Doppler shift – has been revealed in a series of recent Mössbauer experiments, where a radioactive source is fixed at the centre and an absorber is attached to the rim of the rotating disc. This disclosure gives indication to a possible violation of the “clock hypothesis” by Einstein: i.e. the independence of the rate of a clock on its acceleration. At the moment, there seem to be two plausible interpretations of this result: (i) the deviation of the geometry of the rotating disc from that predicted by the general theory of relativity (GTR), or (ii) the existence of a specific maximal acceleration in nature, when transformation between two accelerated frames differs from the corresponding transformation of the relativity theory. We take a closer look at both ways leading to the violation of the clock hypothesis; particularly, by analysing the outcomes of recent experiments in rotating systems and by suggesting a new Mössbauer rotor experiment to determine the most feasible mechanism for testing the dependence of the rate of a clock on its acceleration.

Elaborations on Mössbauer rotor experiments with synchrotron radiation and with usual resonant sources

2018 ◽  
Vol 25 (6) ◽  
pp. 1703-1710 ◽  
Author(s):  
A. L. Kholmetskii ◽  
T. Yarman ◽  
O. Yarman ◽  
M. Arik
Keyword(s):  
Comparative Analysis ◽  
Synchrotron Radiation ◽  
Mössbauer Effect ◽  
Laboratory Frame ◽  
Recent Application ◽  
Mossbauer Effect ◽  
Rotating System ◽  
Rotating Systems ◽  
Methodological Difference ◽  
Resonant Radiation

A comparative analysis of Mössbauer experiments in a rotating system between a recent application using synchrotron radiation [Friedman et al. (2016). Eur. Phys. Lett. 114, 50010; Friedman et al. (2017). J. Synchrotron Rad. 24, 661–666] and usual sources of resonant radiation is carried out. The principal methodological difference between these experiments can be related to the fact that in the former set of experiments the source of the resonant radiation rests in a laboratory frame whereas for the latter set of experiments the source is attached to a rotating system. It is concluded that the utilization of ordinary Mössbauer sources remains the most promising path for further research appertaining to the Mössbauer effect in rotating systems.

Novel Mössbauer experiment in a rotating system: Extra energy shift confirmed

2015 ◽  
Author(s):  
A. L. Kholmetskii ◽  
T. Yarman ◽  
M. Arik ◽  
O.V. Missevitch
Keyword(s):  
Energy Shift ◽  
Rotating System ◽  
Extra Energy

scholarly journals Novel Mössbauer experiment in a rotating system and the extra-energy shift between emission and absorption lines

2016 ◽  
Vol 94 (8) ◽  
pp. 780-789 ◽  
Author(s):  
T. Yarman ◽  
A.L. Kholmetskii ◽  
M. Arik ◽  
B. Akkuş ◽  
Y. Öktem ◽  
...  
Keyword(s):  
Subject Matter ◽  
Energy Shift ◽  
Quantitative Agreement ◽  
Relative Energy ◽  
Absorption Lines ◽  
Rotating System ◽  
Extra Energy ◽  
The Subject

We present the results of a novel Mössbauer experiment in a rotating system, implemented recently at Istanbul University, which yields the coefficient k = 0.69 ± 0.02 within the frame of the expression for the relative energy shift between emission and absorption lines ΔE/E = ku2/c2. This result turned out to be in quantitative agreement with an experiment achieved earlier on the subject matter (Kholmetskii et al. Phys. Scr. 79, 065007 (2009)), and once again strongly pointed to the inequality k > 0.5, revealed originally in (Kholmetskii et al. Phys. Scr. 77, 035302 (2008)) via the re-analysis of Kündig’s experiment (Kündig, Phys. Rev. 129, 2371 (1963)). A possible explanation of the deviation of the coefficient k from the relativistic prediction k = 0.5 is discussed.

Specimen Preparation for Clinical Applications of X-Ray Microanalysis

1990 ◽  
Vol 48 (2) ◽  
pp. 328-329
Author(s):  
J.D. Shelburne ◽  
G.M. Roomans
Keyword(s):  
Carbon Coating ◽  
Clinical Applications ◽  
Point Of View ◽  
Practical Significance ◽  
Sweat Test ◽  
Specimen Preparation ◽  
Tissue Preparation ◽  
X Ray ◽  
Gallbladder Stones ◽  
Clinical Problems

Proper preparative procedures are a prerequisite for the validity of the results of x-ray microanalysis of biological tissue. Clinical applications of x-ray microanalysis are often concerned with diagnostic problems and the results may have profound practical significance for the patient. From this point of view it is especially important that specimen preparation for clinical applications is carried out correctly.Some clinical problems require very little tissue preparation. Hair, nails, and kidney and gallbladder stones may be examined and analyzed after carbon coating. High levels of zinc or copper in hair may be indicative of dermatological or systemic diseases. Nail clippings may be analyzed (as an alternative to the more conventional sweat test) to confirm a diagnosis of cystic fibrosis. X-ray microanalysis in combination with scanning electron microscopy has been shown to be the most reliable method for the identification of the components of kidney or gallbladder stones.A quantitatively very important clinical application of x-ray microanalysis is the identification and quantification of asbestos and other exogenous particles in lung.

X-Ray absorption edge elemental imaging of B. thuringienis

1989 ◽  
Vol 47 ◽  
pp. 212-213
Author(s):  
R. L. Stears
Keyword(s):  
Absorption Edge ◽  
Elemental Distribution ◽  
X Rays ◽  
Differential Absorption ◽  
Synchrotron Source ◽  
High Brightness ◽  
X Ray ◽  
Elemental Imaging ◽  
Cellular Integrity ◽  
X Ray Absorption

Because of the nature of the bacterial endospore, little work has been done on analyzing their elemental distribution and composition in the intact, living, hydrated state. The majority of the qualitative analysis entailed intensive disruption and processing of the endospores, which effects their cellular integrity and composition.Absorption edge imaging permits elemental analysis of hydrated, unstained specimens at high resolution. By taking advantage of differential absorption of x-ray photons in regions of varying elemental composition, and using a high brightness, tuneable synchrotron source to obtain monochromatic x-rays, contact x-ray micrographs can be made of unfixed, intact endospores that reveal sites of elemental localization. This study presents new data demonstrating the application of x-ray absorption edge imaging to produce elemental information about nitrogen (N) and calcium (Ca) localization using Bacillus thuringiensis as the test specimen.

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