scholarly journals Gadolinium contained scintillation glass for neutron detection in a wide energy range.

2021 ◽  
Vol 57 (2) ◽  
pp. 217-223
Author(s):  
M. V. Korzhik
Keyword(s):  
Wide Spectrum ◽  
Neutron Cross Section ◽  
Light Nuclei ◽  
Lithium Silicate ◽  
Wide Energy Range ◽  
Wide Energy ◽  
Li Isotope ◽  
Materials Used ◽  
Detector Materials ◽  
First Time

Inorganic scintillation glasses form a domain of rapidly evolving detector materials used to measure various types of ionizing radiation. The most widespread are lithium-silicate glasses enriched with the 6Li isotope, which are used to register thermal neutrons. At the same time, due to the specificity of the energy dependence of the neutron cross-section of light nuclei, such materials are of little use for the evaluation of epithermal and more highly energetic neutrons. The use of rare earth elements in the composition of glasses makes it possible to increase the sensitivity to neutrons. In the BaO–Gd2O3–SiO2 system, doped with Ce ions, a scintillation glass with a yield of at least 2500 photons / MeV was created for the first time, which permits to create inexpensive detector elements of a significant volume for registering neutrons. It has been shown that a detector based on BaO–Gd2O3–SiO2 glass has satisfactory properties when detecting neutrons in a wide spectrum of their energies.

scholarly journals Study of the process $$e^+e^- \rightarrow \eta \pi ^0\gamma $$ in the energy range $$\sqrt{s} = {1.05-2.00}$$ GeV with the SND detector

2020 ◽  
Vol 80 (11) ◽  
Author(s):  
M. N. Achasov ◽  
A. Yu. Barnyakov ◽  
A. A. Baykov ◽  
K. I. Beloborodov ◽  
A. V. Berdyugin ◽  
...  
Keyword(s):  
Energy Range ◽  
Cross Section ◽  
Center Of Mass ◽  
Wide Energy Range ◽  
Mass Energy ◽  
Center Of Mass Energy ◽  
Wide Energy ◽  
Radiation Processes ◽  
Using Data ◽  
First Time

AbstractThe process $$e^+e^-\rightarrow \eta \pi ^0\gamma $$ e + e - → η π 0 γ is studied in the center-of-mass energy range 1.05–2.00 GeV using data with an integrated luminosity of 94.5 $$\hbox {pb}^{-1}$$ pb - 1 collected by the SND detector at the VEPP-2000 $$e^{+}e^{-}$$ e + e - collider. The $$e^+e^-\rightarrow \eta \pi ^0\gamma $$ e + e - → η π 0 γ cross section is measured for the first time. It is shown that the dominant mechanism of this reaction is the transition through the $$\omega \eta $$ ω η intermediate state. The measured cross section of the subprocess $$e^+e^-\rightarrow \omega \eta \rightarrow \eta \pi ^0\gamma $$ e + e - → ω η → η π 0 γ is consistent with previous measurements in the $$e^+e^-\rightarrow \pi ^+\pi ^-\pi ^0\eta $$ e + e - → π + π - π 0 η mode. It is found, with a significance of $$5.6\sigma $$ 5.6 σ , that the process $$e^+e^-\rightarrow \eta \pi ^0\gamma $$ e + e - → η π 0 γ is not completely described by hadronic vector-pseudoscalar intermediate states. The cross section of this missing contribution, which can originate from radiation processes, e. g. $$e^+e^-\rightarrow a_{0}(1450)\gamma $$ e + e - → a 0 ( 1450 ) γ , is measured. It is found to be 15–20 pb in the wide energy range from 1.3 to 1.9 GeV.

scholarly journals Recent X-ray Observations of Pulsar Nebulae

1996 ◽  
Vol 160 ◽  
pp. 367-374 ◽  
Author(s):  
Nobuyuki Kawai ◽  
Keisuke Tamura
Keyword(s):  
Spectral Characteristics ◽  
High Spectral Resolution ◽  
Wide Energy Range ◽  
Emission Sources ◽  
Diffuse Emission ◽  
X Ray ◽  
Diffuse Sources ◽  
Vela Pulsar ◽  
Wide Energy ◽  
First Time

AbstractResults from the X-ray observations of pulsars with ASCA are presented. The surroundings of pulsars are investigated in detail taking advantage of ASCA’s unique capabilities; high spectral resolution and a high throughput over a wide energy range from 0.4 keV to 10 keV. The spectral characteristics of the nebulae of PSR B1509—58 and the Vela pulsar are spectroscopically investigated. A jet-like feature is found from PSR B1509—58. We detected diffuse emission sources in the vicinity of many pulsars. The high probability of finding such diffuse sources for many pulsars suggests that they exist universally for all the active pulsars, and that they are powered by the pulsars. SNR Kes 32 was imaged in X-ray for the first time. Its X-ray properties can be used to examine its association with the nearby pulsar PSR B1610—50.

scholarly journals ARGO-YBJ: STATUS AND HIGHLIGHTS

2013 ◽  
Vol 53 (A) ◽  
pp. 646-651
Author(s):  
Giuseppe Di Sciascio
Keyword(s):  
Energy Range ◽  
Gamma Ray ◽  
Cosmic Ray ◽  
Current Status ◽  
Wide Energy Range ◽  
Open Problems ◽  
Direct Measurements ◽  
Wide Energy ◽  
First Time ◽  
Gathering Data

The ARGO-YBJ experiment has been gathering data steadily since November 2007 at the YangBaJing Cosmic Ray Laboratory (Tibet, P.R. China, 4300m a.s.l., 606 g/cm2). ARGO-YBJ is confronting various open problems in Cosmic Ray (CR) physics. The search for CR sources is carried out by observing TeV gamma-ray sources, both galactic and extra-galactic. The CR spectrum, composition and anisotropy are measured in a wide energy range (TeV ÷ PeV), thus overlapping direct measurements for the first time. This paper summarizes the current status of the experiment and describes some of the scientific highlights since 2007.

scholarly journals Gamma ray burst studies with THESEUS

2021 ◽  
Author(s):  
G. Ghirlanda ◽  
R. Salvaterra ◽  
M. Toffano ◽  
S. Ronchini ◽  
C. Guidorzi ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Wide Energy Range ◽  
Spectral Evolution ◽  
Imaging Spectrometer ◽  
X Ray ◽  
Compact Binaries ◽  
Wide Energy ◽  
First Time ◽  
Intermediate Redshifts ◽  
Prompt Emission

AbstractGamma-ray Bursts (GRBs) are the most powerful transients in the Universe, over–shining for a few seconds all other γ-ray sky sources. Their emission is produced within narrowly collimated relativistic jets launched after the core–collapse of massive stars or the merger of compact binaries. THESEUS will open a new window for the use of GRBs as cosmological tools by securing a statistically significant sample of high-z GRBs, as well as by providing a large number of GRBs at low–intermediate redshifts extending the current samples to low luminosities. The wide energy band and unprecedented sensitivity of the Soft X-ray Imager (SXI) and X-Gamma rays Imaging Spectrometer (XGIS) instruments provide us a new route to unveil the nature of the prompt emission. For the first time, a full characterisation of the prompt emission spectrum from 0.3 keV to 10 MeV with unprecedented large count statistics will be possible revealing the signatures of synchrotron emission. SXI spectra, extending down to 0.3 keV, will constrain the local metal absorption and, for the brightest events, the progenitors’ ejecta composition. Investigation of the nature of the internal energy dissipation mechanisms will be obtained through the systematic study with XGIS of the sub-second variability unexplored so far over such a wide energy range. THESEUS will follow the spectral evolution of the prompt emission down to the soft X–ray band during the early steep decay and through the plateau phase with the unique ability of extending above 10 keV the spectral study of these early afterglow emission phases.

scholarly journals Investigation of 7Bе population in reactions on nuclei of beryllium and boron with bremsstrahlung gamma-rays in wide energy range

2020 ◽  
Vol 21 (4) ◽  
pp. 302-307
Author(s):  
V.O. Zheltonozhsky ◽  
◽  
D.E. Myznikov ◽  
A.M. Savrasov ◽  
V.I. Slisenko
Keyword(s):  
Energy Range ◽  
Gamma Rays ◽  
Cross Sections ◽  
Theoretical Calculations ◽  
Wide Energy Range ◽  
Point Energy ◽  
End Point ◽  
Software Packages ◽  
Wide Energy ◽  
First Time

The average cross-sections were measured at the first time for 7Bе population at bremsstrahlung end-point energies 40 and 55 MeV and for the 10B(γ,t)7Bе reaction at bremsstrahlung end-point energy 20 MeV. The theoretical calculations carried out within the framework of the software packages EMPIRE-3.2 and TALYS-1.9 demonstrate the domination of the nonstatistical processes.

scholarly journals PRECISE COSMIC RAYS MEASUREMENTS WITH PAMELA

2013 ◽  
Vol 53 (A) ◽  
pp. 712-717
Author(s):  
A. Bruno ◽  
O. Adriani ◽  
G. C. Barbarino ◽  
G. A. Bazilevskaya ◽  
R. Bellotti ◽  
...  
Keyword(s):  
Cosmic Rays ◽  
Secondary Production ◽  
Cosmic Ray ◽  
Light Nuclei ◽  
Energy Spectra ◽  
Wide Energy Range ◽  
Pamela Experiment ◽  
Production Models ◽  
The Galaxy ◽  
Wide Energy

The PAMELA experiment was launched on board the Resurs-DK1 satellite on June 15th 2006. The apparatus was designed to conduct precision studies of charged cosmic radiation over a wide energy range, from tens of MeV up to several hundred GeV, with unprecedented statistics. In five years of continuous data taking in space, PAMELA accurately measured the energy spectra of cosmic ray antiprotons and positrons, as well as protons, electrons and light nuclei, sometimes providing data in unexplored energetic regions. These important results have shed new light in several astrophysical fields like: an indirect search for Dark Matter, a search for cosmological antimatter (anti-Helium), and the validation of acceleration, transport and secondary production models of cosmic rays in the Galaxy. Some of the most important items of Solar and Magnetospheric physics were also investigated. Here we present the most recent results obtained by the PAMELA experiment.

scholarly journals The Spin Studies in Few-Body Systems at Nuclotron

2016 ◽  
Vol 40 ◽  
pp. 1660074 ◽  
Author(s):  
V. P. Ladygin ◽  
I. Dobrin ◽  
V. V. Fimushkin ◽  
D. A. Finogenov ◽  
S. G. Genchev ◽  
...  
Keyword(s):  
Short Range ◽  
Spin Structure ◽  
Ion Source ◽  
Light Nuclei ◽  
Wide Energy Range ◽  
Analyzing Powers ◽  
Spin Effects ◽  
Polarized Deuterons ◽  
Wide Energy ◽  
Future Plans

Recent results on spin effects in few nucleon systems obtained at Nuclotron-JINR are presented. The data on the deuteron analyzing powers in different reactions in the wide energy range demonstrate the sensitivity to the short-range spin structure of the light nuclei. The future plans on the studies with polarized deuterons from new polarized ion source at Nuclotron will be reported.

scholarly journals Revealing the constituents of Egypt’s oldest beer using infrared and mass spectrometry

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Mohamed A. Farag ◽  
Moamen M. Elmassry ◽  
Masahiro Baba ◽  
Renée Friedman
Keyword(s):  
Large Scale ◽  
Beer Brewing ◽  
Chemical Signatures ◽  
Chemical Determination ◽  
Materials Used ◽  
High Level ◽  
Beer Production ◽  
First Time ◽  
Detailed Chemical

Abstract Previous studies have shown that the Ancient Egyptians used malted wheat and barley as the main ingredients in beer brewing, but the chemical determination of the exact recipe is still lacking. To investigate the constituents of ancient beer, we conducted a detailed IR and GC-MS based metabolite analyses targeting volatile and non-volatile metabolites on the residues recovered from the interior of vats in what is currently the world’s oldest (c. 3600 BCE) installation for large-scale beer production located at the major pre-pharaonic political center at Hierakonpolis, Egypt. In addition to distinguishing the chemical signatures of various flavoring agents, such as dates, a significant result of our analysis is the finding, for the first time, of phosphoric acid in high level probably used as a preservative much like in modern beverages. This suggests that the early brewers had acquired the knowledge needed to efficiently produce and preserve large quantities of beer. This study provides the most detailed chemical profile of an ancient beer using modern spectrometric techniques and providing evidence for the likely starting materials used in beer brewing.

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