Observations of the background component of cosmic X rays

1968 ◽  
Vol 46 (10) ◽  
pp. S466-S469 ◽  
Author(s):  
M. Matsuoka ◽  
M. Oda ◽  
Y. Ogawara ◽  
S. Hayakawa ◽  
T. Kato
Keyword(s):  
Energy Spectrum ◽  
Energy Range ◽  
Counting Rate ◽  
Galactic Center ◽  
Field Of View ◽  
X Rays ◽  
Background Component

The background component of cosmic X rays was observed using collimators of different fields of view. It was found that there existed a component with the counting rate proportional to the field of view. The intensity of the background component was found to be essentially uniform except in the region including the Sco X-1 source and sources in the vicinity of the galactic center. The energy spectrum was nearly flat in the energy range between 4 and 8 keV, and the intensity was 0.45 ± 0.09 photon cm−2 s−1 keV−1. The shape of the spectrum was checked by comparison with the spectrum of Sco X-1.

scholarly journals Simultaneous measurements of X-rays and electrons during a pulsating aurora

1998 ◽  
Vol 16 (2) ◽  
pp. 148-160 ◽  
Author(s):  
N. Østgaard ◽  
J. Stadsnes ◽  
K. Aarsnes ◽  
F. Søraas ◽  
K. Måseide ◽  
...  
Keyword(s):  
Energy Spectrum ◽  
Energy Range ◽  
Energetic Particle ◽  
Good Method ◽  
Electron Energy Spectrum ◽  
Electron Precipitation ◽  
X Rays ◽  
X Ray ◽  
Electron Spectra ◽  
Simultaneous Measurements

Abstract. The PULSAUR II rocket was launched from Andøya Rocket Range at 23.43 UT on 9 February 1994 into a pulsating aurora. In this paper we focus on the observations of precipitating electrons and auroral X-rays. By using models it is possible to deduce the electron energy spectrum from X-ray measurements. Comparisons are made between the deduced electron fluxes and the directly measured electron fluxes on the rocket. We found the shape of the observed and the deduced electron spectra to fit very well, with almost identical e-folding energies in the energy range from 10 ke V to ~60–80 ke V. For the integrated fluxes from 10.8 to 250 ke V, we found a discrepancy of 30% . By combining two models, we have found a good method of deducing the electron precipitation from X-ray measurements. The discrepancies between calculations and measurements are in the range of the uncertainties in the measurements.Key words. Ionospheric particle precipitation · Magnetospheric physics · Annual phenomena · Energetic particle

scholarly journals Sudden changes in the intensity of high energy X-rays from Sco X-1

1970 ◽  
Vol 37 ◽  
pp. 104-106
Author(s):  
P. C. Agrawal ◽  
S. Biswas ◽  
G. S. Gokhale ◽  
V. S. Iyengar ◽  
P. K. Kunte ◽  
...  
Keyword(s):  
Counting Rate ◽  
High Energy ◽  
Field Of View ◽  
X Rays ◽  
Background Counting Rate ◽  
X Ray ◽  
The North ◽  
Residual Atmosphere ◽  
Flux Gate ◽  
Background Counting

In this note we wish to report briefly the observation of sudden changes in the intensity of Sco X-1 by a factor of about 3 recorded in the energy interval 29.9–52.3 keV on December 22, 1968 between 04 h 27 m and 05 h 53 m UT. The observation was made with an X-ray telescope flown in a balloon from Hyderabad, India. The balloon was launched at 0200 hr UT and reached the ceiling of 7.5 g/cm2 of residual atmosphere at 0435 hr UT. The X-ray telescope consisted of a NaI(T1) crystal with an area of 97.3 cm2 and thickness 4 mm, surrounded by both active and passive collimators. The telescope was mounted on an oriented platform which was programmed to look in four specified directions successively, of azimuths, Φ=0°, 110°, 180° and 310° (Φ=0° being North and Φ=90°, West), spending about 4 min in each direction during a cycle of period of about 16 min. The axis of the telescope was inclined at an angle of 32° with respect to the zenith. A pair of crossed flux gate magnetometers provided information every 8.2 sec on the azimuth of the telescope. The pulse heights from the X-ray detector were sorted into several channels extending from 10 to 120 keV. An Am241 source came into the field of view of the telescope once in 15 min for about 30 sec to provide in-flight calibration of the detector. The meridian transit of Sco X-1 was at 0454 hr UT. Just before the balloon reached the ceiling Sco X-1 was in the field of view of the telescope for 3 min and 41 sec. After the balloon reached ceiling, Sco X-1 was in the field of view of the telescope on five occasions between 0443 and 0553 hr UT. During the last observation, however, the balloon had lost altitude by about 1 g/cm2. The excess counts due to Sco X-1 were obtained by subtracting the counting rates corresponding to the North direction which did not include any known X-ray sources. The observation on Sco X-1 in the 1st cycle was made while the balloon was still ascending and consequently the interposed grammage was changing from 10.5 to 9.7 g/cm2. However, for the energy range under consideration, the change in the background counting rate was not significant and there cannot be any doubt regarding the genuineness of the excess counts recorded.

X-ray flux from discrete sources

1970 ◽  
Vol 37 ◽  
pp. 88-93
Author(s):  
U. R. Rao ◽  
E. V. Chitnis ◽  
A. S. Prakasarao ◽  
U. B. Jayanthi
Keyword(s):  
Energy Spectrum ◽  
Energy Range ◽  
Low Energy ◽  
X Rays ◽  
X Ray ◽  
Preliminary Results ◽  
Absolute Flux ◽  
The Absolute

Preliminary results of two rocket flights carrying X-ray payloads conducted from Thumba Equatorial Rocket Launching Station (TERLS), Trivandrum, India, on November 3, 1968, and November 7, 1968, respectively, are presented. The results indicate the first evidence for the existence of low energy X-ray flux in the energy range 2–20 keV from Cen-X2 source since the reported extinction in May, 1967. The energy spectrum and the absolute flux of X-rays from Cen-X2, Sco-X1 and Tau-X1 are presented and compared with other observations.

Observational results on diffuse cosmic X-rays: (Invited discourse)

1970 ◽  
Vol 37 ◽  
pp. 260-268
Author(s):  
Minoru Oda
Keyword(s):  
Energy Spectrum ◽  
Energy Range ◽  
Present Status ◽  
X Rays ◽  
X Ray ◽  
Normal Galaxies ◽  
The Universe

The present status of observations of the diffuse cosmic X-rays is discussed. The energy spectrum in the energy range 1–100 keV has been well established. The flux around 0.25 keV appears to be rather high. The basis of the classical argument that the integration of normal galaxies in the universe is not sufficient to explain the diffuse X-ray flux is re-examined. Recent observations around 0.25 keV are discussed and results are compiled.

scholarly journals Observations on diffuse cosmic X-rays in the energy range 20–120 keV

1970 ◽  
Vol 37 ◽  
pp. 289-296 ◽  
Author(s):  
P. C. Agrawal ◽  
S. Biswas ◽  
G. S. Gokhale ◽  
V. S. Iyengar ◽  
P. K. Kunte ◽  
...  
Keyword(s):  
Energy Range ◽  
Plastic Scintillator ◽  
Effective Area ◽  
Field Of View ◽  
Photographic Film ◽  
Geometrical Factor ◽  
X Rays ◽  
Diffuse Background ◽  
Balloon Experiments ◽  
Isotropic Radiation

In this paper we present observations of the diffuse background X-rays in the energy range 20–120 keV, based on two balloon experiments carried out from Hyderabad (latitude 17.6°N, longitude 78.5°E), India. The flights were made on April 28, 1968 and December 22, 1968. The detector used was a NaI(Tl) crystal of effective area 97.3 cm2 and thickness 4 mm. The crystal was surrounded both by active and passive collimators. The passive collimator was a cylindrical graded shield of lead, tin, and copper, and the active collimator was a plastic scintillator surrounding the shield. The FWHM of the telescope was 18.6° and the geometrical factor for isotropic radiation 13.2 cm2 sr. The pulses from the NaI crystal were sorted into ten contiguous channels extending from 17 to 124 keV. An Am241 source came into the field of view of the telescope periodically and provided in-flight calibration of the detector. All the information was recorded on photographic film.

scholarly journals Spectral Tomography for 3D Element Detection and Mineral Analysis

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 598
Author(s):  
Jose R. A. Godinho ◽  
Gabriel Westaway-Heaven ◽  
Marijn A. Boone ◽  
Axel D. Renno
Keyword(s):  
Energy Spectrum ◽  
3D Imaging ◽  
X Rays ◽  
3D Images ◽  
Characterization Methods ◽  
X Ray ◽  
Additional Information ◽  
Mineral Phases ◽  
Spectral Computed Tomography

This paper demonstrates the potential of a new 3D imaging technique, Spectral Computed Tomography (sp-CT), to identify heavy elements inside materials, which can be used to classify mineral phases. The method combines the total X-ray transmission measured by a normal polychromatic X-ray detector, and the transmitted X-ray energy spectrum measured by a detector that discriminates between X-rays with energies of about 1.1 keV resolution. An analysis of the energy spectrum allows to identify sudden changes of transmission at K-edge energies that are specific of each element. The additional information about the elements in a phase improves the classification of mineral phases from grey-scale 3D images that would be otherwise difficult due to artefacts or the lack of contrast between phases. The ability to identify the elements inside the minerals that compose ore particles and rocks is crucial to broaden the application of 3D imaging in Earth sciences research and mineral process engineering, which will represent an important complement to traditional 2D imaging mineral characterization methods. In this paper, the first applications of sp-CT to classify mineral phases are showcased and the limitations and further developments are discussed.

scholarly journals A comprehensive Monte Carlo study to design a novel multi-nanoparticle loaded nanocomposites for augmentation of attenuation coefficient in the energy range of diagnostic X-rays

2021 ◽  
Vol 27 (4) ◽  
pp. 279-289
Author(s):  
Elahe Sayyadi ◽  
Asghar Mesbahi ◽  
Reza Eghdam Zamiri ◽  
Farshad Seyyed Nejad
Keyword(s):  
Monte Carlo ◽  
Energy Range ◽  
Radiation Protection ◽  
Experimental Studies ◽  
Rubber Matrix ◽  
Photon Flux ◽  
Monte Carlo Code ◽  
X Rays ◽  
Wide Range ◽  
Shielding Properties

Abstract Introduction: The present study aimed to investigate the radiation protection properties of silicon-based composites doped with nano-sized Bi2O3, PbO, Sm2O3, Gd2O3, WO3, and IrO2 particles. Radiation shielding properties of Sm2O3 and IrO2 nanoparticles were investigated for the first time in the current study. Material and methods: The MCNPX (2.7.0) Monte Carlo code was utilized to calculate the linear attenuation coefficients of single and multi-nano structured composites over the X-ray energy range of 10–140 keV. Homogenous distribution of spherical nanoparticles with a diameter of 100 nm in a silicon rubber matrix was simulated. The narrow beam geometry was used to calculate the photon flux after attenuation by designed nanocomposites. Results: Based on results obtained for single nanoparticle composites, three combinations of different nano-sized fillers Sm2O3+WO3+Bi2O3, Gd2O3+WO3+Bi2O3, and Sm2O3+WO3+PbO were selected, and their shielding properties were estimated. In the energy range of 20-60 keV Sm2O3 and Gd2O3 nanoparticles, in 70-100 keV energy range WO3 and for photons energy higher than 90 keV, PbO and Bi2O3 nanoparticles showed higher attenuation. Despite its higher density, IrO2 had lower attenuation compared to other nanocomposites. The results showed that the nanocomposite containing Sm2O3, WO3, and Bi2O3 nanoparticles provided better shielding among the studied samples. Conclusions: All studied multi-nanoparticle nanocomposites provided optimum shielding properties and almost 8% higher attenuation relative to single nano-based composites over a wide range of photon energy used in diagnostic radiology. Application of these new composites is recommended in radiation protection. Further experimental studies are suggested to validate our findings.

scholarly journals NSLS-II MX beamlines FMX for micro-crystallography & AMX for highly automated MX

2014 ◽  
Vol 70 (a1) ◽  
pp. C1733-C1733
Author(s):  
Martin Fuchs ◽  
Robert Sweet ◽  
Lonny Berman ◽  
Dileep Bhogadi ◽  
Wayne Hendrickson ◽  
...  
Keyword(s):  
Energy Range ◽  
Structure Determination ◽  
Optical Systems ◽  
Photon Flux ◽  
X Rays ◽  
Macromolecular Crystallography ◽  
Binding Studies ◽  
X Ray ◽  
Array Detectors ◽  
Broad Energy Range

We present the final design of the x-ray optical systems and experimental stations of the two macromolecular crystallography (MX) beamlines, FMX and AMX, at the National Synchrotron Light Source-II (NSLS-II). Along with its companion x-ray scattering beamline, LIX, this suite of Advanced Beamlines for Biological Investigations with X-rays (ABBIX, [1]) will begin user operation in 2016. The pair of MX beamlines with complementary and overlapping capabilities is located at canted undulators (IVU21) in sector 17-ID. The Frontier Microfocusing Macromolecular Crystallography beamline (FMX) will deliver a photon flux of ~5x10^12 ph/s at a wavelength of 1 Å into a spot of 1 - 50 µm size. It will cover a broad energy range from 5 - 30 keV, corresponding to wavelengths from 0.4 - 2.5 Å. The highly Automated Macromolecular Crystallography beamline (AMX) will be optimized for high throughput applications, with beam sizes from 4 - 100 µm, an energy range of 5 - 18 keV (0.7 - 2.5 Å), and a flux at 1 Å of ~10^13 ph/s. Central components of the in-house-developed experimental stations are a 100 nm sphere of confusion goniometer with a horizontal axis, piezo-slits to provide dynamic beam size changes during diffraction experiments, a dedicated secondary goniometer for crystallization plates, and sample- and plate-changing robots. FMX and AMX will support a broad range of biomedical structure determination methods from serial crystallography on micron-sized crystals, to structure determination of complexes in large unit cells, to rapid sample screening and data collection of crystals in trays, for instance to characterize membrane protein crystals and to conduct ligand-binding studies. Together with the solution scattering program at LIX, the new beamlines will offer unique opportunities for advanced diffraction experiments with micro- and mini-beams, with next generation hybrid pixel array detectors and emerging crystal delivery methods such as acoustic droplet ejection. This work is supported by the US National Institutes of Health.

A new method to reject X-rays from energy range 30 to 150 keV

1969 ◽  
Vol 69 (2) ◽  
pp. 303-308 ◽  
Author(s):  
A. Bui Van ◽  
G. Vedrenne
Keyword(s):  
Energy Range ◽  
New Method ◽  
X Rays
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