Measurement Of Very High Masses Per Unit Area In A Flash X-Rays Experiment Calibration Problems

1983 ◽  
Author(s):  
Jean-Pierre Gauthier ◽  
Rene Guix
Keyword(s):  
Unit Area ◽  
X Rays ◽  
Very High

High-energy resolution in X-ray scattering with the spectrometer INELAX. I. The principles and the test instrument

1991 ◽  
Vol 24 (6) ◽  
pp. 1042-1050 ◽  
Author(s):  
E. Burkel ◽  
B. Dorner ◽  
Th. Illini ◽  
J. Peisl
Keyword(s):  
Energy Resolution ◽  
High Energy ◽  
Bragg Angle ◽  
High Energy Resolution ◽  
X Rays ◽  
Test Results ◽  
X Ray Scattering ◽  
Radiation Sources ◽  
Very High Energy ◽  
Very High

Very high-energy resolution measurements using X-rays can be achieved by extreme backreflection (Bragg angle close to 90°) from perfect crystals. This technique, combined with the high intensity of X-rays emitted by synchrotron-radiation sources, allowed the development of the instrument INELAX for inelastic scattering experiments. The principles and test results are discussed.

scholarly journals Monitoring of the radio galaxy M 87 at Very High Energy with MAGIC during a low emission state between 2012 and 2015

2016 ◽  
Vol 12 (S324) ◽  
pp. 164-167
Author(s):  
C. Arcaro ◽  
P. Bangale ◽  
M. Manganaro ◽  
D. Mazin ◽  
P. Colin ◽  
...  
Keyword(s):  
Radio Galaxy ◽  
Spectral Energy Distribution ◽  
Photon Emission ◽  
High Energy ◽  
Spectral Energy ◽  
X Rays ◽  
Low Emission ◽  
Very High Energy ◽  
Alternative Scenarios ◽  
Very High

AbstractWe present the preliminary results from observing the nearby radio galaxy M 87 for 156 hours (between the years 2012 and 2015) with the MAGIC telescopes, which lead to a significant very high energy (VHE, E > 100 GeV) detection of the source in quiescent states each year. Our VHE analysis combined with quasi-simultaneous data at other energies (from gamma-rays, X-rays, optical and radio) provides a unique opportunity to study the source variability and its broadband spectral energy distribution, which is found to disfavour a one-zone synchrotron/synchrotron self-Compton model. Therefore, other alternative scenarios for the photon emission are explored. We also find that the VHE emission is compatible with being produced close to the source radio core as previous data already indicated. A detailed paper presenting full results of the observing campaign is in preparation.

scholarly journals Very High Energy γ-Ray Generation Near The Light Cylinder of an Axisymmetric Rotator: Cos-B Like γ-Ray Sources

1992 ◽  
Vol 128 ◽  
pp. 207-208
Author(s):  
S. V. Bogovalov ◽  
YU. D. Kotov
Keyword(s):  
High Energy ◽  
Relativistic Electrons ◽  
X Rays ◽  
Inverse Compton Scattering ◽  
Light Cylinder ◽  
Radiation Spectra ◽  
Inverse Compton ◽  
Very High Energy ◽  
Γ Ray ◽  
Very High

AbstractSuper-hard γ-ray radiation spectra have been calculated. This radiation is generated near the velocity-of-light cylinder through the process of inverse-Compton scattering of relativistic electrons by thermal photons radiated by a neutron star. These calculations have been compared with observations of the Crab and Vela pulsars at 1000-GeV γ-ray energies. A correlation between γ-ray flares and those in soft (Ex ≃ lkeV) X-rays are predicted.

scholarly journals A New Chapter in Hard X-rays of the M87 AGN

Proceedings ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 9
Author(s):  
Ka-Wah Wong ◽  
Rodrigo S. Nemmen ◽  
Jimmy A. Irwin ◽  
Dacheng Lin
Keyword(s):  
High Energy ◽  
X Rays ◽  
X Ray ◽  
Accretion Flow ◽  
Relativistic Jet ◽  
Very High Energy ◽  
Γ Ray ◽  
High Energy Emission ◽  
First Time ◽  
Very High

The nearby M87 hosts an exceptional relativistic jet. It has been regularly monitored in radio to TeV bands, but little has been done in hard X-rays ≳10 keV. For the first time, we have successfully detected hard X-rays up to 40 keV from its X-ray core with joint Chandra and NuSTAR observations, providing important insights to the X-ray origins: from the unresolved jet or the accretion flow. We found that the hard X-ray emission is significantly lower than that predicted by synchrotron self-Compton models introduced to explain very-high-energy γ -ray emission above a GeV. We discuss recent models to understand these high energy emission processes.

On the Primary X-Ray Analyzer

1965 ◽  
Vol 9 ◽  
pp. 508-514 ◽  
Author(s):  
Shizuo Kimoto ◽  
Masayuki Sato ◽  
Hitoshi Kamada ◽  
Takuzi Ui
Keyword(s):  
Electron Beams ◽  
Spectrochemical Analysis ◽  
Specimen Surface ◽  
X Rays ◽  
Light Elements ◽  
X Ray ◽  
Very High

AbstractThe primary X-ray analyzer is used for nondestructive spectrochemical analysis of solid specimens. Accelerated electron beams bombard the specimen surface directly and generate primary X-rays which are measured in a vacuum spectrometer. The method of primary X-ray spectroscopy is superior to the fluorescence X-ray spectroscopy because (1) detectable sensitivity for such light elements as magnesium and aluminum is very high, and (2) the correction of the measured value for self-absorption of X-rays by the specimen itself is low. The performance of the instrument and applications are reported.

Branched ears in wheat and yield determination

1972 ◽  
Vol 23 (4) ◽  
pp. 541 ◽  
Author(s):  
HM Rawson ◽  
KN Ruwali
Keyword(s):  
Unit Area ◽  
Field Conditions ◽  
Spikelet Number ◽  
Yield Production ◽  
Yield Determination ◽  
Very High

Differentiation of the branched ear of a semidwarf mutant wheat is described for plants grown under irrigated field conditions, and compared with cultivars bearing simple ears. With a very high spikelet number per ear (more than SO), and few grains per spikelet (a maximum of three), the branched ear offers a radically different concept for yield production. Yields per unit area of the current branched material were not as high as for Kalyan Sona, India's premier variety, but did exceed those for Late Mexico 120. Better yields could be expected if the random sterility of spikelets within the branched ear, first apparent early in spikelet differentiation, were reduced. However, individual fertile ears filled up to 128 grains weighing 4.8 g in the better plants.

Very high energy y-rays from Cygnus X-3

1981 ◽  
Vol 301 (1462) ◽  
pp. 633-634 ◽  
Keyword(s):  
Light Curve ◽  
High Energy ◽  
Crimean Astrophysical Observatory ◽  
Sharp Peak ◽  
X Rays ◽  
Very High Energy ◽  
Time Variations ◽  
Comparison Of The Results ◽  
Very High

Very high energy y-rays (above 10 12 eV) from Cyg X-3 have been observed for 7 years at the Crimean Astrophysical Observatory by means of the Cherenkov technique. These observations enable us to find the derivative with time of the 4.8 hour periodicity. As is well known, the observations of X -rays have revealed time variations of the Cyg X-3 period (see, for instance, Eisner et al. 1979). The ‘light’ curve for very high energy y-rays has a sharp peak lasting 15 minutes and differs significantly from the ‘light’ curve for X-rays. For this reason the comparison of the results in these two regions is important.

Field of researches and applications domains for compact and large-scale DPF devices: Current assets, problems and essentials

2014 ◽  
Vol 32 ◽  
pp. 1460314
Author(s):  
V. A. Gribkov
Keyword(s):  
Large Scale ◽  
Intermediate Energy ◽  
X Rays ◽  
Intermediate Energies ◽  
Low Energies ◽  
Plasma Diode ◽  
Radiation Material ◽  
Dynamic Quality ◽  
Very High ◽  
Radiation Material Science

Examination of the most important processes taking place in Dense Plasma Focus (DPF) device that lead to the production of very bright flashes of neutrons and X-rays is presented. It is shown that the current abruption (CA) phenomenon accompanied by the plasma-diode formation plays the key role in these events. Issues of matching of different primary loads with plasma inductive storage and subsequently with plasma diode are discussed. It is shown that at the intermediate energies it is possible to attain the perfect matching. Results in some applications of medium-sized DPF obtained recently in radiation material science, dynamic quality control, biology and medicine are presented. It is shown that for better matching at very high energies the classical intermediate energy compressing element can be used. Besides schemes with laser support switching are discussed. Extrapolations of DPF phenomena to very high and very low energies with their feasibility are examined. Envisioned applications of such huge and tiny DPF devices in power production, medicine and electronics are discussed.

scholarly journals Skin friction of the wind on the Earth's surface

1916 ◽  
Vol 92 (637) ◽  
pp. 196-199 ◽  
Keyword(s):  
Flat Plate ◽  
Skin Friction ◽  
Solid Surface ◽  
Unit Area ◽  
Tangential Force ◽  
Mean Velocity ◽  
Small Surface ◽  
The Mean ◽  
General Velocity ◽  
Very High

The mechanism by means of which momentum is transmitted to a solid surface, in order that it may exert a drag on a fluid flowing past it, is at present understood only very imperfectly. It seems certain, however, that the law of dynamical similarity is applicable to skin friction; if therefore it were possible to measure the tangential force exerted by the wind as it blows over a large tract of land, it should be equal to the skin friction on a similar small surface when subjected to the action of the very high wind which would correspond with the same value of l V/ v . In reducing the tract of land to a similar small flat plate, the trees and houses would be reduced to a mere roughness on the plate. It is to be expected therefore that, if the skin friction on unit area of the earth's surface be expressed in the form F = kp Q 2 s , (1) Q s being the wind velocity near the surface and p the density of air, the constant k will be the same as the constant which would be found in the laboratory by experimenting with a small, slightly roughened plate, if a sufficiently high value of l V/ v , could be obtained. It should be noticed, however, that the velocity which should be compared with is the velocity close to the solid surface and not the general velocity of the air in the case of a flat plate, or the mean velocity over a cross section in the case of flow in a pipe.

Sign in / Sign up

Export Citation Format

Share Document