scholarly journals Characterization of new primary air kerma standards for dosimetry in Co-60, Cs-137 and Ir-192 gamma ray sources

2021 ◽  
Vol 16 (10) ◽  
pp. P10014
Author(s):  
S. Pojtinger ◽  
L. Büermann
Keyword(s):  
Gamma Ray ◽  
Air Kerma

scholarly journals Introducing the HD+B model for pulsar wind nebulae: a hybrid hydrodynamics/radiative approach

2020 ◽  
Vol 494 (3) ◽  
pp. 4357-4370
Author(s):  
B Olmi ◽  
D F Torres
Keyword(s):  
Gamma Ray ◽  
High Energy ◽  
Theoretical Modelling ◽  
X Rays ◽  
Pulsar Wind Nebulae ◽  
New Approach ◽  
Energy Gamma ◽  
Radiative Model ◽  
Pulsar Wind

ABSTRACT Identification and characterization of a rapidly increasing number of pulsar wind nebulae is, and will continue to be, a challenge of high-energy gamma-ray astrophysics. Given that such systems constitute -by far- the most numerous expected population in the TeV regime, such characterization is important not only to learn about the sources per se from an individual and population perspective, but also to be able to connect them with observations at other frequencies, especially in radio and X-rays. Also, we need to remove the emission from nebulae in highly confused regions of the sky for revealing other underlying emitters. In this paper, we present a new approach for theoretical modelling of pulsar wind nebulae: a hybrid hydrodynamic-radiative model able to reproduce morphological features and spectra of the sources, with relatively limited numerical cost.

Characterization of Uranium Ore Samples by HPGe Gamma-Ray Spectroscopy

2020 ◽  
Vol 67 (4) ◽  
pp. 654-661 ◽  
Author(s):  
Thomas Marchais ◽  
Bertrand Perot ◽  
Cedric Carasco ◽  
Jean-Luc Ma ◽  
Pierre-Guy Allinei ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Uranium Ore ◽  
Gamma Ray Spectroscopy

scholarly journals Agronomic and molecular characterization of gamma ray induced banana (Musa sp.) mutants using a multivariate statistical algorithm

Euphytica ◽  
2011 ◽  
Vol 178 (2) ◽  
pp. 151-158 ◽  
Author(s):  
Rosa Karla Nogueira Pestanana ◽  
Edson Perito Amorim ◽  
Cláudia Fortes Ferreira ◽  
Vanusia Batista de Oliveira Amorim ◽  
Larissa Santos Oliveira ◽  
...  
Keyword(s):  
Molecular Characterization ◽  
Gamma Ray ◽  
Multivariate Statistical ◽  
Musa Sp ◽  
Statistical Algorithm

Development and Characterization of Large La-Halide Gamma-Ray Scintillators for Future Planetary Missions

2007 ◽  
Vol 54 (4) ◽  
pp. 873-878 ◽  
Author(s):  
Stefan Kraft ◽  
Erik Maddox ◽  
Ernst-Jan Buis ◽  
Alan Owens ◽  
Francesco G. A. Quarati ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Planetary Missions

Assessing Bypassed Hydrocarbons

2021 ◽  
Author(s):  
Stanley Oifoghe ◽  
Nora Alarcon ◽  
Lucrecia Grigoletto
Keyword(s):  
Continental Shelf ◽  
Reservoir Characterization ◽  
Gamma Ray ◽  
West African ◽  
The Novel ◽  
The West ◽  
Present Case Study ◽  
Novel Model

Abstract Hydrocarbons are bypassed in known fields. This is due to reservoir heterogeneities, complex lithology, and limitations of existing technology. This paper seeks to identify the scenarios of bypassed hydrocarbons, and to highlight how advances in reservoir characterization techniques have improved assessment of bypassed hydrocarbons. The present case study is an evaluation well drilled on the continental shelf, off the West African Coastline. The targeted thin-bedded reservoir sands are of Cenomanian age. Some technologies for assessing bypassed hydrocarbon include Gamma Ray Spectralog and Thin Bed Analysis. NMR is important for accurate reservoir characterization of thinly bedded reservoirs. The measured NMR porosity was 15pu, which is 42% of the actual porosity. Using the measured values gave a permeability of 5.3mD as against the actual permeability of 234mD. The novel model presented in this paper increased the porosity by 58% and the permeability by 4315%.

scholarly journals The characterization of the gamma-ray signal from the central Milky Way: A case for annihilating dark matter

2016 ◽  
Vol 12 ◽  
pp. 1-23 ◽  
Author(s):  
Tansu Daylan ◽  
Douglas P. Finkbeiner ◽  
Dan Hooper ◽  
Tim Linden ◽  
Stephen K.N. Portillo ◽  
...  
Keyword(s):  
Dark Matter ◽  
Milky Way ◽  
Gamma Ray

Fabrication and Characterization of MOVPE-Grown CdTe-on-Si Heterojunction Diode-Type Gamma-Ray Detectors

2008 ◽  
Vol 37 (9) ◽  
pp. 1391-1395 ◽  
Author(s):  
M. Yokota ◽  
K. Yasuda ◽  
M. Niraula ◽  
K. Nakamura ◽  
H. Ohashi ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Heterojunction Diode ◽  
Gamma Ray Detectors ◽  
Fabrication And Characterization

VERITAS OBSERVATIONS OF RELATIVISTIC OUTFLOWS IN LOW- AND INTERMEDIATE-FREQUENCY-PEAKED BL LAC OBJECTS

2014 ◽  
Vol 28 ◽  
pp. 1460178
Author(s):  
◽  
HEIKE PROKOPH
Keyword(s):  
Gamma Ray ◽  
Intermediate Frequency ◽  
Bl Lac Objects ◽  
Bl Lacertae ◽  
Bl Lac ◽  
Bl Lacs ◽  
Gamma Ray Telescopes ◽  
Very High

The majority of blazars detected at very high energies (VHE; E > 100 GeV) are high-frequency-peaked BL Lac objects (HBLs). Low- and intermediate-frequency-peaked BL Lacs (LBLs/IBLs with synchrotron-peak frequencies in the infrared and optical regime) are generally more powerful, more luminous, and have a richer jet environment than HBLs. However, only a handful of these IBL and LBLs have been detected by ground-based gamma-ray telescopes, typically during high-flux states. The VERITAS array has been monitoring five known VHE LBLs/IBLs since 2009: 3C 66A, W Comae, PKS 1424+240, S5 0716+714 and BL Lacertae, with typical exposures of 5-10 hours per year. The results of these long-term observations are presented, including a bright, subhour-scale VHE flare of BL Lacertae in June 2011, the first low-state detections of 3C 66A and W Comae, and the detection and characterization of the IBL B2 1215+30.

Characterization of Materials for a Hydrogen-Based Economy by Cold Neutron Prompt Gamma-Ray Activation Analysis

2008 ◽  
Vol 1098 ◽  
Author(s):  
Rick Paul ◽  
Lei Raymond Cao
Keyword(s):  
Activation Analysis ◽  
Hydrogen Storage ◽  
Gamma Ray ◽  
Cold Neutron ◽  
Proton Conductors ◽  
Prompt Gamma ◽  
Hydrogen Storage Materials ◽  
Storage Materials ◽  
Characterization Of Materials

AbstractAn instrument for cold neutron prompt gamma-ray activation analysis (PGAA) at the NIST Center for Neutron Research (NCNR) has proven useful for the chemical characterization of hydrogen storage materials and other materials of importance to a hydrogen-based economy. The detection limit for hydrogen is less than 10 mg/kg for most materials. Potential hydrogen storage materials that have been characterized by PGAA include single-wall carbon nanotubes with and without boron doping, porous carbons, lithium magnesium imides, and ternary hydrides of various elements. The capability to allow in situ hydrogenation and characterization of materials is currently under development. PGAA has also been used to characterize materials used in hydrogen fuel cells, including solid proton conductors, polymer membrane, and proton exchange membranes. Future upgrades to the instrument will improve detection limits and functionality of the instrument.

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