In situ study of the 41Ar plume released from the Ignalina NPP

Open Physics ◽  
2008 ◽  
Vol 6 (4) ◽  
Author(s):  
Rimvydas Jasiulionis ◽  
Linas Vyčinas ◽  
Andrej Rožkov

AbstractThe 41Ar gamma ray radiation was registered using the in situ method in the vicinity of the Ignalina nuclear power plant (NPP). The sum of gamma rays, that are reaching the HPGe detector, situated along the wind direction, from a number of plume segments and which are registered in the energy range of about 1.29 MeV, is calculated. An independent technological regime of the operating reactor method of the determination of the 41Ar emission rate from NPP stack is introduced.

2021 ◽  
Vol 9 (4) ◽  
pp. 27-33
Author(s):  
Duy Quang Nguyen ◽  
Van Cuong Trinh ◽  
Tuan Anh Tran ◽  
Van Doanh Ho ◽  
Thi Tho Nguyen ◽  
...  

The k0-based internal mono-standard (IM) method was first proposed for the concentration analysis of samples of non-standard geometry in the 2000s. The method has demonstrated several advantages such as the elimination of gamma-ray self-attenuation and geometrical effects. On the other hand, the accuracy of the method principally depends on the in situ relative detection efficiency, which requires to be obtained in each measurement. Therefore, the relative detection efficiency is always under consideration for the improvement of the analysis results. The present paper describes a simple and automatic procedure for the determination of the relative efficiency using one or more activation products emitting gamma rays over a considered range of the spectrum. The procedure can be applied for INAA and PGNAA analysis.


2008 ◽  
Vol 17 (09) ◽  
pp. 1343-1349 ◽  
Author(s):  
S. D. VERGANI ◽  
D. MALESANI ◽  
E. MOLINARI

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.


2016 ◽  
Vol 44 ◽  
pp. 1660237
Author(s):  
Huda Al-Sulaiti ◽  
Tabassum Nasir ◽  
K. S. Al Mugren ◽  
N. Alkhomashi ◽  
N. Al-Dahan ◽  
...  

The goal of this study was to establish the first baseline measurements for radioactivity concentration of the artificial radionuclide [Formula: see text]Cs in soil samples collected from the Qatarian peninsula. The work focused on the determination of the activity concentrations levels of man-made radiation in 129 soil samples collected across the landscape of the State of Qatar. All the samples were collected before the most recent accident in Japan, “the 2011 Fukushima Dai-ichi nuclear power plant accident”. The activity concentrations have been measured via high-resolution gamma-ray spectrometry using a hyper-pure germanium detector situated in a low-background environment with a copper inner-plated passive lead shield. A radiological map showing the activity concentrations of [Formula: see text]Cs is presented in this work. The concentration was[Formula: see text]found to range from 0.21 to 15.41 Bq/kg. The highest activity concentration of [Formula: see text]Cs was observed in sample no. 26 in North of Qatar. The mean value was found to be around 2.15 ± 0.27 Bq/kg. These values lie within the expected range relative to the countries in the region. It is expected that this contamination is mainly due to the Chernobyl accident on 26 April 1986, but this conclusion cannot be confirmed because of the lack of data before this accident.


2002 ◽  
Vol 61 (1) ◽  
pp. 75-89 ◽  
Author(s):  
F. Gering ◽  
P. Kiefer ◽  
S. Fesenko ◽  
G. Voigt

Science ◽  
2021 ◽  
Vol 372 (6546) ◽  
pp. 1081-1085
Author(s):  
◽  
H. Abdalla ◽  
F. Aharonian ◽  
F. Ait Benkhali ◽  
E. O. Angüner ◽  
...  

Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events. We report the detection of very-high-energy (VHE) gamma rays from the afterglow of GRB 190829A, between 4 and 56 hours after the trigger, using the High Energy Stereoscopic System (H.E.S.S.). The low luminosity and redshift of GRB 190829A reduce both internal and external absorption, allowing determination of its intrinsic energy spectrum. Between energies of 0.18 and 3.3 tera–electron volts, this spectrum is described by a power law with photon index of 2.07 ± 0.09, similar to the x-ray spectrum. The x-ray and VHE gamma-ray light curves also show similar decay profiles. These similar characteristics in the x-ray and gamma-ray bands challenge GRB afterglow emission scenarios.


1977 ◽  
Vol 55 (2) ◽  
pp. 175-179 ◽  
Author(s):  
H. E. Bosch ◽  
V. M. Silbergleit ◽  
M. Davidson ◽  
J. Davidson

An investigation of the gamma–gamma ray angular correlations following the decay of 109Pd was made by using a Ge(Li) semiconductor counter and NaI(Tl) gamma-ray detector. Coincidences measurements at six different angles were made between the 311 keV gamma ray (gated in the movable counter) and 390, 413, 424, 551, and 558 keV gamma rays (displayed in a multichannel analyzer (MCA)). Chance coincidences as well as coincidence background were taken into account. The following spins and mixing ratios were determined: 701 keV level 3/2, δ(390) = 0.19 ± 0.06; 724 keV level 3/2, δ(413) = 0.18 ± 0.05; 735 keV level 5/2, δ(424) = −0.27 ± 0.03; 862 keV level 5/2, δ(551) = −0.28 ± 0.04; 869 keV level 5/2, δ(558) = −0.26 ± 0.05. The result indicates that the anisotropies are consistent with mixing ratios less than 28% in all cases.


Sign in / Sign up

Export Citation Format

Share Document