Determination of number, energy and dose albedos of some marbles used in external wall cladding of buildings for 59.54 keV gamma-rays

The measurement and analysis of the intensity–direction correlation of gamma rays emitted in cascade following heavy-particle capture are treated. A procedure is discussed which is based upon the expansion of the triple-correlation intensity in terms of the set of angular functions orthogonal over the space of the emission (or absorption) directions. This is in contrast to the usual method which expresses the correlation in terms of Legendre polynomials. In the analysis procedure proposed, the population parameters are found directly from the original data, with the gamma-radiation mixing ratios assigned. The least-squares equations representing the best fit to the data contain the population parameters linearly and are solved by a standard computer program which also gives the value of χ2. The true solution is then found by varying the mixing ratios until a minimum in χ2 is reached. In addition to the determination of the population parameters of the decaying state and the mixing ratios of the gamma rays in the cascade, the calculation of the error matrix of these quantities, and the calculation of the formation parameters in simple capture, are described.

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Determination of stable isotope ratios using nuclear reaction analysis coupled with a particle–gamma coincidence method

Journal of Analytical Atomic Spectrometry ◽

10.1039/d0ja00283f ◽

2021 ◽

Author(s):

Paula Rangel Pestana Allegro ◽

Márcia de Almeida Rizzutto ◽

Nemitala Added ◽

Vitor Ângelo Paulino de Aguiar ◽

Dennis Lozano Toufen ◽

...

Keyword(s):

Nuclear Reaction ◽

Gamma Rays ◽

Charged Particles ◽

Isotope Ratios ◽

Nuclear Reaction Analysis ◽

Stable Isotope Ratios ◽

Coincidence Method ◽

Medium Energy ◽

Gamma Coincidence

This study presents an alternative method to determine isotope ratios using a medium energy accelerator and simultaneously measuring the charged particles and gamma-rays produced in a nuclear reaction.

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A precise determination of small intensity differences as obtained for gamma-rays in linear-polarization experiments

Nuclear Instruments and Methods in Physics Research ◽

10.1016/0167-5087(84)90487-3 ◽

1984 ◽

Vol 224 (1-2) ◽

pp. 327-330 ◽

Cited By ~ 9

Author(s):

Georg Winter ◽

Joachim Döring

Keyword(s):

Gamma Rays ◽

Linear Polarization ◽

Precise Determination ◽

Small Intensity

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Comparative Effect of 200 KV. X-Rays and Gamma Rays on the Pupae of Drosophila Melanogaster: I. Determination of "Equivalent Roentgen" Value for Gamma Rays: II. Summation Experiments with X-Rays and Gamma Rays

The American Journal of Cancer ◽

10.1158/ajc.1938.565 ◽

1938 ◽

Vol 32 (4) ◽

pp. 565-581 ◽

Cited By ~ 6

Author(s):

J. H. Muller

Keyword(s):

Drosophila Melanogaster ◽

Gamma Rays ◽

X Rays ◽

Comparative Effect

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THE INTERPLAY OF PROMPT AND AFTERGLOW EMISSION IN GRB 060418

International Journal of Modern Physics D ◽

10.1142/s0218271808012899 ◽

2008 ◽

Vol 17 (09) ◽

pp. 1343-1349 ◽

Cited By ~ 2

Author(s):

S. D. VERGANI ◽

D. MALESANI ◽

E. MOLINARI

Keyword(s):

Gamma Rays ◽

Spectral Properties ◽

Gamma Ray ◽

Early Time ◽

Lorentz Factor ◽

X Ray ◽

Central Engine ◽

Low Energies ◽

Prompt Emission

We present observations of the early afterglow emission of GRB 060418. Thanks to the simultaneous coverage at optical, X-ray and gamma-ray wavelengths, we can detect and separate the external shock emission (visible in the optical and late X-ray data) and the central engine activity (early X and gamma rays). The two components are clearly distinguished based on temporal and spectral properties. The detection of the afterglow onset (in the optical) allows the determination of the fundamental fireball properties, namely its bulk Lorentz factor and total energy. The early time X-ray flare closely resembles the prompt emission gamma-ray pulses in its temporal profile, being wider at low energies and showing lags between the hard and soft bands. This provides a strong suggestion that X-ray flares are a continuation of the prompt emission.

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INVESTIGATION OF THE RADIOPROTECTIVE EFFECT OF ORTHOVANADATE IN MICE AFTER TOTAL BODY IRRADIATION

Radiation Protection Dosimetry ◽

10.1093/rpd/ncz192 ◽

2019 ◽

Vol 186 (2-3) ◽

pp. 149-154

Author(s):

Zuzana Šinkorová ◽

Alžběta Filipová ◽

Jiřina Vávrová ◽

Jaroslav Pejchal ◽

Lenka Andrejsová ◽

...

Keyword(s):

Gamma Rays ◽

Large Scale ◽

Lethal Dose ◽

Response Prediction ◽

Increasing Risk ◽

Pre Treatment ◽

High Doses ◽

Total Body ◽

Lymphocyte Populations

Abstract The increasing risk of acute large-scale exposure of ionising irradiation on the population underlines the necessity of developing effective radioprotective and mitigating agents. The aim of this work was to investigate the effect of sodium orthovanadate pre-treatment on mice exposed to high doses of gamma rays (from 5 to 13 Gy). The determination of median lethal dose within 30 days confirmed that orthovanadate applied to total-body-irradiated mice intra-peritoneally has a radioprotective but not a mitigating effect. With orthovanadate pre-treatment, the composition of cellularity in the bone marrow improved substantially and the main lymphocyte populations restored during the first month after irradiation. These findings contribute to ‘gap-filling’ in radioprotective effects and demonstrate the importance of haematological parameters in radiation–response prediction.

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Summary of Future Space Observations of Solar Irradiances at Different Wavelengths

International Astronomical Union Colloquium ◽

10.1017/s025292110002460x ◽

1994 ◽

Vol 143 ◽

pp. 101-108

Author(s):

Vicente Domingo

Keyword(s):

Gamma Rays ◽

Solar Irradiance ◽

Infrared Light ◽

New Techniques ◽

Future Space ◽

Form Part ◽

History Of ◽

Almost All ◽

Near Future

The variations of solar irradiance can only be measured with a reasonable precision from space for almost all wavelengths. Yet the history of solar irradiance determinations is, with few exceptions, the history of efforts to patch the infrequent or too discontinuous space-based measurements by devising mechanisms for proxy determination of solar irradiance fluxes from ground-based obtained parameters. Although it appears that in the near future the situation will not be too different, there is some increase in the coverage of the spectral range that will be monitored. From gamma-rays to infrared light there are instruments that are now operating (e.g. GOES, Yohkoh, UARS) or are planned to operate in approved space missions (e.g. SOHO, ATLAS), or form part of proposed, not yet approved, missions. New techniques are being developed specifically for the measurement of solar irradiance variations with increased precision (e.g. cryogenic radiometer) in the next generation of space-borne measurements.

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