MONTE CARLO SIMULATIONS OF dd REACTION PARAMETERS STUDY AT ULTRA-LOW ENERGY RANGE USING PLASMA HALL ACCELERATOR AND DEUTERIZED TARGETS

2012 ◽  
Vol 21 (11) ◽  
pp. 1250089 ◽  
Author(s):  
M. FILIPOWICZ ◽  
V. M. BYSTRITSKY ◽  
G. N. DUDKIN ◽  
F. M. PENK'OV ◽  
A. V. PHILIPPOV

This paper presents results of the application Monte Carlo method to analyze data from the interaction of deuteron beams with metallic targets saturated with deuterium. The SRIM software was used to generate energy spectrum of ions passing the target. These spectra were used to calculate the neutron yields from dd reactions in energy range 7–12 keV of incident deuteron beams. The calculated outputs were compared with the experimental data for the determination of the electron screening potential for dd reactions. The calculations were performed using two different values of the beam energy spread (FWHM) equal 1% and 16%. It was shown that plasma beams with a relatively high spread (16%) were almost as good a tool as the traditional accelerator with mono-energy beam related to the study of the reaction within an ultra-low energy region.

2011 ◽  
Vol 10 (4) ◽  
pp. 261-271 ◽  
Author(s):  
James C.L. Chow ◽  
Amir M. Owrangi

AbstractWe study how mucosal dose in the oral or nasal cavity depends on the irradiated small segmental photon fields varying with beam energy, beam angle and mucosa thickness. Dose ratio (mucosal dose with bone underneath to dose at the same point without bone) reflecting the dose enhancement due to the bone backscatter was determined by Monte Carlo simulation (EGSnrc-based code), validated by measurements. Phase space files based on the 6 and 18 MV photon beams with small field size of 1 × 1 cm2, produced by a Varian 21 EX linear accelerator, were generated using the BEAMnrc Monte Carlo code. Mucosa phantoms (mucosa thickness = 1, 2 and 3 mm) with and without a bone under the mucosa were irradiated by photon beams with gantry angles varying from 0 to 30°. Doses along the central beam axis in the mucosa and the dose ratio were calculated with different mucosa thicknesses. For the 6 MV photon beams, the dose at the mucosa-bone interface increased by 44.9–41.7%, when the mucosa thickness increased from 1 to 3 mm for the beam angle ranging from 0 to 30°. These values were lower than those (58.8–53.6%) for the 18 MV photon beams with the same beam angle range. For both the 6 and 18 MV photon beams, depth doses in the mucosa were found to increase with an increase of the beam angle. Moreover, the dose gradient in the mucosa was greater for the 18 MV photon beams compared to the 6 MV. For the dose ratio, it was found that the dose enhancement due to the bone backscatter increased with a decrease of mucosa thickness, and was more significant at both the air-mucosa and mucosa-bone interface. Mucosal dose with bone was investigated by Monte Carlo simulations with different experimental configurations, and was found vary with the beam energy, beam angle and mucosa thickness for a small segmental photon field. The dosimetric information in this study should be considered when searching for an optimized treatment strategy to minimize the mucosal complications in the head-and-neck intensity-modulated radiation therapy.


KnE Energy ◽  
2018 ◽  
Vol 3 (1) ◽  
pp. 21
Author(s):  
Yu Penionzhkevich ◽  
Yu Sobolev ◽  
V Samarin ◽  
M Naumenko

The paper presents the results of measurement of the total cross sections for reactions 4,6He + Si and 6,7,9Li + Si in the beam energy range 5−50 A⋅MeV. The enhancements of the total cross sections for reaction 6He + Si compared with reaction 4He + Si, and 9Li + Si compared with reactions 6,7Li + Si have been observed. The performed microscopic analysis of total cross sections for reactions 6He + Si and 9Li + Si based on numerical solution of the time-dependent Schrödinger equation for external neutrons of projectile nuclei 6He and 9Li yielded good agreement with experimental data.


2010 ◽  
Vol 66 (3-4) ◽  
pp. 585-686 ◽  
Author(s):  
S. Actis ◽  
◽  
A. Arbuzov ◽  
G. Balossini ◽  
P. Beltrame ◽  
...  

2007 ◽  
Vol 21 (21) ◽  
pp. 1383-1390
Author(s):  
DE-HUA LIN ◽  
PING ZOU ◽  
ZHONG-WEI ZHANG ◽  
HONG-LEI WANG ◽  
JUN PAN ◽  
...  

In this paper, we study the elementary excitations and energy spectrum proposed by L. D. Landau in liquid helium II. On the basis of the energy spectrum for the phonons and rotons, we put forward a uniform expression of energy spectrum in liquid helium II, which is limited in a specific temperature range. By using the wave function for low energy excited states proposed by R. P. Feynman or the modified one proposed by Feynman and Cohen, it can be found that the estimated energy spectrum is quite different from the experimental data, especially for the region with large wave numbers. By proposing an improved form for the wave function, we re-analyze the energy spectrum in liquid helium II, and our results show a better agreement with the experimental data.


2020 ◽  
Author(s):  
Anders Lindanger ◽  
Martino Marisaldi ◽  
Nikolai Østgaard ◽  
Andrey Mezentsev ◽  
Torstein Neubert ◽  
...  

<p>Terrestrial Gamma-ray Flashes (TGFs) are sub milliseconds bursts of high energy photons associated with lightning flashes in thunderstorms. The Atmosphere-Space Interactions Monitor (ASIM), launched in April 2018, is the first space mission specifically designed to detect TGFs. We will mainly focus on data from the High Energy Detector (HED) which is sensitive to photons with energies from 300 keV to > 30 MeV, and include data from the Low Energy Detector (LED) sensitive in 50 keV to 370 keV energy range. Both HED and LED are part of the Modular X- and Gamma-ray Sensor (MXGS) of ASIM.<br><br>The energy spectrum of TGFs, together with Monte Carlo simulations, can provide information on the production altitude and beaming geometry of TGFs. Constraints have already been set on the production altitude and beaming geometry using other spacecraft and radio measurements. Some of these studies are based on cumulative spectra of a large number of TGFs (e.g. [1]), which smooth out individual variability. The spectral analysis of individual TGFs has been carried out up to now for Fermi TGFs only, showing spectral diversity [2]. Crucial key factors for individual TGF spectral analysis are a large number of counts, an energy range extended to several tens of MeV, a good energy calibration as well as knowledge and control of any instrumental effects affecting the measurements.</p><p>We strive to put stricter constraints on the production altitude and beaming geometry, by comparing Monte Carlo simulations to energy spectra from single ASIM TGFs. We will present the dataset and method, including the correction for instrumental effects, and preliminary results on individual TGFs.</p><p>Thanks to ASIM’s large effective area and low orbital altitude, single TGFs detected by ASIM have much more count statistics than observations from other spacecrafts capable of detecting TGFs. ASIM has detected over 550 TGFs up to date (January 2020), and ~115 have more than 100 counts. This allows for a large sample for individual spectral analysis.</p><p>References:</p><ol><li>Dwyer, J. R., and D. M. Smith (2005), A comparison between Monte Carlo simulations of runaway breakdown and terrestrial gamma-ray flash observations, Geophys. Res. Lett., 32, L22804, doi:10.1029/2005GL023848.</li> <li>Mailyan et al. (2016), The spectroscopy of individual terrestrial gamma-ray flashes: Constraining the source properties, J. Geophys. Res. Space Physics, 121, 11,346–11,363, doi:10.1002/2016JA022702.</li> </ol>


2009 ◽  
Vol 24 (02n03) ◽  
pp. 603-606
Author(s):  
◽  
FILIP KŘÍŽEK

The HADES collaboration studied dielectron production in C + C , p + p , and d + p reactions, with the main goal to investigate properties of vectors mesons through their dielectron decay. Production of e+e- pairs in Ar + KCl collisions at a beam energy of 1.756 A GeV was measured recently by the collaboration and preliminary results of the experimental data analysis will be reported. Pair spectra will be compared with a prediction of a thermal model based on the Monte Carlo event generator Pluto.


1997 ◽  
Vol 3 (S2) ◽  
pp. 885-886 ◽  
Author(s):  
Pierre Hovington ◽  
Dominique Drouin ◽  
Raynald Gauvin ◽  
David C. Joy

The range of electrons for a given beam energy and atomic number is one of the most valuable piece of information a microscopist must know before carrying out qualitative and quantitative analysis of heterogeneous samples in a scanning electron microscope (SEM). The frequently used parametrization of Kanaya & Okayama is only « valid » at high energy (EO > 10 keV). However, with the advent of Field Emission Gun SEM (FEGSEM) most of the effort has been toward low energy analysis where no parametrization is available yet. In this paper, the parametrization of the range of electrons at low energy as a function of atomic number and beam energy will be presented for both the backscattered and the internal electrons.The distribution of the maximum depth reached by 250 k electrons generated by the CASINO Monte Carlo program2 was used to compute the range for 10 elements at 20 energies.


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