bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design, construction, and measurement of electromagnetic steering magnet for 25-MeV electron accelerator system
Authors: Kitisri P , Khangrang N , Kitisri T , Rimjaem S 
Published: February 2023

Abstract
Mid-infrared and terahertz free-electron laser (MIR/THz FEL) facility is under the construction at the PBP-CMU Electron Linac Laboratory (PCELL) in Chiang Mai University. For producing MIR-FEL, electron beams with an energy of 25 MeV accelerated by a radio-frequency linear accelerator (RF linac) are required. Transporting the 25-MeV electron beam from the linac to the MIR-FEL station requires small dipole magnets for steering the electron beams along the beamline. This work focuses on the design, construction, and measurement of an electromagnetic steering magnet for controlling the electron beam trajectory. A computer software, CST Studio Suite 2022 is used for the 3D magnetic field simulation of the magnet. The physical length of the magnet and the diameter of copper coil are decided based on the simulation and calculation results. After the construction, a hall probe with a measuring system controlled by a computer program is used to measure the magnetic field for comparison with the simulation results. From simulated and calculated results, the steering magnet with a length of 40 mm and the coil with a diameter of 1.06 mm was chosen. At an applied current of 1.8 A, this steering magnet can bend the 25-MeV electron beam with a bending angle of 13.7 mrad. The measured magnetic field is consistent with the simulated results. The advantage of this steering magnet is that it can be assembled on a square frame for steering the beam in both horizontal and vertical direction. It can also be used for the THz-FEL beamline, which requires the electron beam with an energy of 10-16 MeV.
Construction and tests of phosphor view screen station for monitoring transverse profile of electron beam at PCELL
Authors: Khangrang N , Kitisri P , Saisut J , Techakaew K , Rimjaem S 
Published: February 2023

Abstract
Development of an accelerator-based light source for generating coherent terahertz (THz) and mid-infrared (MIR) free-electron laser (FEL) is ongoing at the PBP-CMU Electron Linac Laboratory (PCELL). For producing high quality radiation, suitable electron beam property is necessary. In particle accelerator technology, transverse beam distribution and profile can be measured by using several techniques. The beam monitoring using view screen station is one of popular and effective methods. At PCELL, we use stations consisting of phosphor screen equipped with CCD camera to monitor, measure and record the beam image along the accelerator system and beamlines. The phosphor screen was chosen due to its high spatial resolution. The phosphor film is uniformly coated on a thin aluminium plate. Its green emission when electrons hitting the screen is matched well with the respond of the CCD camera. The screen can be moved in and out from the vacuum chamber using the air pressurized linear actuator. This paper presents about design, construction and tests of the screen stations at PCELL. The resolution of measurements for beam transverse profile and emittance is also be discussed.
Preliminary study of supersonic molecular beam injection in Thailand Tokamak-1 using 3D fluid model
Authors: Rongpuit Kitti , Wisitsorasak Apiwat , Promping Jiraporn 
Published: February 2023

Abstract
Successful operation of a tokamak relies on effective and appropriate methods of plasma fueling. The development plan of Thailand Tokamak-1 (TT-1) will employ the supersonic molecular beam injection (SMBI) which delivers the fueling gas more effectively and deeper than the gas puffing method. In this work, we study the effect of SMBI on the plasma transport of TT-1 plasma by using 3D fluid simulation. The model includes the continuity equation, energy balance equation, momentum equation, continuity of fuel equation, and momentum of fuel. BOUT++ is then used to solve these equations by a finite difference method with the field-aligned coordinates in the edge region. The simulation shows that when hydrogen fuel gas is by the SMBI method from the low-field side into the plasma with a speed of 1000 m/s, the electron density in the edge locally rises as a result of the dissociation and ionization. The ion and electron temperatures then drop. After that, the density spread over the whole plasma volume within about 10 ms. When the injection speed increases, it results in a deeper penetration length of the fuel deposition.
G4beamline simulation for rotating telescope at SLRI BTF
Authors: Kaewjai Jetnipit , Kobdaj Chinorat , Kittimanapun Kritsada , Laojamnongwong Natthawut , Poonsawat Wanchaloem 
Published: February 2023

Abstract
A plan to upgrade the ALICE Inner Tracking System has been proposed, and the Monolithic Active Pixel Sensor, a novel silicon sensor technology, will be employed. The silicon sensor is planned to be investigated with a rotating telescope at the Synchrotron Light Research Institute Beam Test Facility using a 1.2 GeV electron beam. A part of this work is to investigate the pixel sensor telescope when the angle of the Device Under Test (DUT) plane changes. Simulation has been performed with the G4beamline software. Once a G4beamline simulation is completed, a ROOT file is produced. Beam profiles and correlation plots are then analyzed. This data was used to calculate the scattering angle, which was found to be between 0.171 and 0.178 mrad when the DUT plane is perpendicular to the test beam. Furthermore, the simulation result has been compared and agrees with the theoretical calculation within 4.8% error.
Natural and anthropogenic radioactivity and radiological hazard indices in organic Sangyod rice samples collected from Don Pradu sub-district in Pak Phayun district in Phatthalung province, Thailand
Authors: Kessaratikoon P , Charoenmak P , Changkit N , Boonkrongcheep R 
Published: February 2023

Abstract
It is well known that Thai people and many other Asian countries consume rice as the main dish. Minor contamination of natural and anthropogenic radionuclides in rice dishes may cause illness, fever or unwell for no apparent reason. For this reason, the research team was interested in the measurement and analysis of the concentrations of natural and anthropogenic radionuclides in 28 samples of organic Sangyod rice from courtesy of rice farmers in the Don Pradu sub-district, Pak Phayun District, Songkhla province. In addition, the research team was also received courtesy of the National Institute of Nuclear Technology (Public Organization) or TINT to use semiconductor detector measuring instruments and gamma spectrometry analysis systems for this research. It was found that the mean specific activity values of 40K, 226Ra, 232Th and 137Cs were 24.11 ± 2.01, 0.28 ± 0.07, 0.17 ± 0.06 and 0.10 ± 0.03 Bq/kg, respectively. The four relevant radiological indices which were gamma-absorbed dose rate (D), radium equivalent activity (Raeq), external hazard index (Hex) and annual external effective dose rate (AEDout), were also calculated and presented. Furthermore, the excess lifetime cancer risk (ELCR(outdoor)) was also evaluated by using the AEDout value from the investigated area. The results of this research were taken to compare with the values measured by the Office of Atoms for Peace (OAP) and research groups that have been measured and analyzed both at home and abroad. In conclusion, the results in this study were found to be lower than the values recommended by some international organizations and is safe for consumers and farmers who produce organic Sang Yod rice in the study area.
3D range-modulators for proton therapy: near field simulations with FLUKA and comparison with film measurements
Authors: Charuchinda W , Horst F , Simeonov Y , Schuy C , Penchev P , Poulsen P , Sitarz M , Busold S , Reidel C-A , Folkerts M , Krieger M , Suwonjandee N , Asavapibhop B , Durante M , Zink K , Weber U 
Published: February 2023

Abstract
The 3D range-modulator is a device used in particle delivery systems that can create a highly conformal and homogeneous dose distribution in the target volume with mono-energetic beams, providing an option for high dose-rate FLASH therapy. In the normal case, the modulators are positioned at a typical distance of 30-50 cm in front of the target in order to avoid the fluence ripples resulting from the periodic structure of the modulators. FLUKA Monte Carlo simulation package was used to investigate the fluence distributions of protons penetrating through the 2D range-modulator, the simplified version of the 3D range-modulator, and to determine the minimum distance at which the fluence is homogeneous enough for the treatment. To implement the complex geometry of the modulator in FLUKA, a dedicated FLUKA user routine was developed for the simulation of the periodic pin structures. The highest fluence ripple occurred at a few centimetres behind the modulators and then faded away as the distance increased, which can be described by the edge-scattering effect and later by the blur-out of the overlapping contributions from the pins. Moreover, the dose distribution in water was investigated, particularly for small distances between the modulators and the water phantom. Furthermore, the Monte Carlo results were compared with radiochromic film measurements irradiated with a 3D-printed range modulator and showed a good qualitative agreement. Prospectively, for low modulator-to-target distances, the strong dose inhomogeneities which appear in the proximal part of the target, could introduce additionally a kind of ‘mini beam’ normal-tissue sparing by the 3D range-modulators.
The Hubble tension problem with variation of the speed of light from Pantheon supernova dataset
Authors: Chantavat T 
Published: February 2023

Abstract
We investigate how the tension with the Hubble parameter between early-time and late-time observations could be alleviated with the deviation in the speed of light model. In order to test the model, the data of 1,048 spectroscopically confirmed type Ia supernova with redshift range 0.01 < z < 2.3 from Pantheon Supernova is analysed. We found that the deviation in the local speed of light Δc/c = (-0.115 ± 5.087) × 10−5 and the temporal deviation in the speed of light (1/c)(dc/dt) = (7.20 ± 23.34) × 10−18 yr−1 when combining the Pantheon supernova dataset with other constraints. Our result shows that the data prefers sightly higher value of the speed of light in the past albeit with a large uncertainty. The model alleviates the Hubble tension problem by reducing the Hubble parameter to 71.72 ± 1.40 km s−1 Mpc−1 closer to the early-time value.
Phased-resolved pulse energy distribution of PSR J1825–0935
Authors: Intrarat N , Jaroenjittichai P 
Published: February 2023

Abstract
Pulsars are rapidly rotating and highly magnetized neutron stars, that radiate non-thermal radio beams from their magnetic poles. The radio emission of pulsars generally remains stable over ∼1,000 averaging pulses, but some pulsars exhibit interesting features in emission variations on short and long timescales. Here, we report an update on the analysis of the phase-resolved pulse-to-pulse energy distribution of PSR J1825-0935, which has two different emission modes, Bright and Quiet modes. We analyze the energy distribution of each mode separately and found that the pulse profile’s main component energy distribution is well described by a log-normal distribution in the Bright mode and inconclusive for the Quiet mode.
Maser polarization simulation in the circumstellar envelope of an evolving star
Authors: Phetra M , Gray Malcolm D , Asanok K , Kramer Busaba H , Sugiyama K , Chanapote T , Nuntiyakul W 
Published: February 2023

Abstract
An important phenomenon in a pulsing AGB (Asymptotic Giant Branch) star is the variability of its circumstellar envelope. The study of stimulated radiation called SiO maser (microwave amplification by stimulated emission of radiation) in the inner edge of the envelope shows fluctuations in polarization during the stellar pulsation period which is caused by the unstable magnetic field around the AGB star and needs to be investigated in order to understand it. We simulate the maser signal and polarization by using a computer code to describe the circumstellar envelope of the AGB star for comparison with the observations. The methods, i) Generate the energy transition of the stimulation matrix ii) Simulate the first stimulation from an electric field background iii) Convert the radiation to the frequency domain by using Fourier transform iv) Simulate the observation by amplifying radiation along a line of sight within the medium toward an observation position. At this stage, we set the tubular maser cloud with a constant magnetic field strength toward the observer. The program can simulate the maser signal and polarization, brighter when stimulating with a longer medium; the simulated polarization agrees well with expectations for this magnetic field orientation. Further works need to be carried out by testing this program with many cases to explain the obtained data from actual observations.
A computational study of the gas-phase interstellar formose-like reactions
Authors: Wongkummoon P , Keyen U , Nimmanpipug P , Rimjaem S , Suwannajak C 
Published: February 2023

Abstract
Understanding the extraterrestrial origin of ribose, as one of the sub-units of ribonucleic acid (RNA), is crucial to anticipating the formation of the building blocks of life under interstellar medium (ISM) conditions. Under ordinary atmospheric conditions, the formation of sugar is suggested to occur through the formose reaction, where formaldehyde is solely used as the precursor in each of the iterative steps of the formation process. On the other hand, sugar synthesis under ISM conditions has evidently been shown to be significantly different from the terrestrial formose reactions due to the extremely low density of molecules and the very low temperature. In this study, we theoretically investigate the formose-like reactions for ribose formation catalyzed by a single proton through the mean of computer simulation based on first-principles density functional theory (DFT). The ribose formation reactions are modelled in the absence of solvation effects at absolute zero temperature to mimic the extremely low pressure and temperature found in ISM. We observe that the presence of a proton gives rise to a more thermodynamically stable complex of the two reactive carbonyl compounds by bridging their oxygen atoms as required for the iterative formose reaction to proceed. In order to form a new carbon-carbon bond through an iterative process, only the region where the additional formaldehyde attaches to the existed protonated carbonyl compound is of great importance. The energy barriers for all the iterative steps during the ribose formation are similar, i.e., ∼67 kcal mol−1. Our findings show that a single proton can act as an efficient catalyst for the gas-phase ribose formation reactions in the absence of solvent effects. The results also suggest that ribose formation can preferentially occur via the formose pathway in the presence of protons, which are abundantly presented in ISM.
Multi-frequency variabilities: blazar classification and statistical properties
Authors: Yoyponsan R , Sawangwit U , Komonjinda S 
Published: February 2023

Abstract
Blazars are a class of active galactic nuclei whose jets are aligned with the observer’s line of sight. They are powerful multi-frequency emitters that exhibit rapid and violent variation. Classification of blazars requires multi-frequency observation which may be able to achieve through careful planning. However, in the age of automated surveys, we might be able to complete the same task via data mining and machine learning. In this work, we explore the possibility of using the data from robotic surveys for blazar classifications, particularly the variability of their multi-frequency light curves. The 5
th
edition of the Roma-BZCAT is used as our reference blazar catalog. The optical light curves of blazar studied here are taken from the Zwicky Transient Facility (ZTF) public Data Release 4 (2018-2020). The distributions of variability and fractional variability amplitudes in g and r bands are presented and compared for BL Lacs and FSRQs. The Principle Component Analysis (PCA) is then applied to various features extracted from the discrete correlation function (DCF) between the two bands as well as the variability and fractional variability amplitudes of the two bands. Although, our machine learning application for the the BL Lac-FSRQ classification shows unpromising result, the PCA has shown that around 80% of the populations can be explained with 13 features which mainly are the DCF-based ones.
FDTD investigation of adiabatic optical coupling between Silicon nitride and Germanium-based optical structures for energy-efficient photonic integration
Authors: Khongpetch Natdanai , Chaisakul Papichaya , Traiwattanapong Worawat , Chiangga Surasak , Limsuwan Pichet 
Published: February 2023

Abstract
This paper aims to investigate the potential of a direct integration between Si3N4 waveguides and Germanium(Ge)-based structures, which are considered two of the most promising silicon(Si)-compatible materials for passive and active functions for Si-based energy-efficient photonics, respectively. This paper focuses on investigating the vertical coupling scheme between these materials employing a tapered structure of the Ge-based layer using 2D FDE and 3D FDTD simulations, to match the optical mode from a passive Si3N4 waveguide to the Ge-based layer and vice versa. The expected optical coupling performance will be reported, and its dependence on the unavoidable fabrication variation in the coupling region will be also investigated. Additionally, the coupling performance of the vertical coupling approach compared to the previous investigation between a Si waveguide and a Ge layer will be addressed.
Recent Research Progress in Electrochromic Materials for Intelligent Stealth(Visible and Infrared): A review
Authors: Long Xueyuan , Lei Xue , Du Haiquan , Mehmood Ahmar , Li Xixi , Liu Xiongzhang 
Published: February 2023

Abstract
Stealth technology is critical for the existence and the employment of the modern combat weapons systems. Electrochromic materials, which are known as a kind of novel intelligent stealth materials with multi-coloring effect under dynamic control, shows reversible color and emittance change under applied electric filed. Current emerging EC technologies utilizing electrochromism being widely used in intelligent stealth to produce more enhanced effects than traditional static options. This review mainly discusses recent advancement in the electrochromic materials with focus on its applications in the intelligent stealth technologies. Firstly, the principle and classification of electrochromic materials are presented along with summary of recent developments in electrochromism. Secondly, the potential applications of inorganic and organic electrochromism in visible and infrared stealth bands are highlighted. Finally, the challenges and further development approaches are emphasized; it will be intended to underline the future perspectives in realizing intelligent stealth for different applications.
Fractal Research on Surface Topography of Profile Milling CFRT
Authors: Xinman Yuan , Zhiqin Hu , Pan Luo , Ke Ma , Jie Xu , Pingfa Feng , Feng Feng 
Published: February 2023

AbstractCarbon Fiber Reinforced Thermoplastic Composites (CFRT) are recognized as a new generation of advanced strategic materials due to their excellent mechanical properties and high recycling rate. However, in the milling process, affected by the coupling of force and thermal, the heat-sensitive resin in CFRP is easily softened and deformed, leading to difficulties in achieving high-quality material removal. Especially in the complex and long-period surface milling process, the processed surface has a complex and irregular microscopic topography, hard to be accurately characterized by traditional roughness measurement methods. To evaluate the surface quality of CFRT profile after milling more precisely, in this paper, the influence of cutting parameters on fractal dimension is systematically analyzed by solving the image gray surface based on the fractal dimension algorithm and calculating the fractal dimension of the surface after milling via the variational method. The experimental results show that the surface fractal dimension of thermoplastic composites processed by PCD milling cutter is between 2.46 and 2.52, and the sensitivity ranking of fractal dimension to cutting parameters is:vf<Ae<Ap.
Optimal parameters estimation for K-edge subtraction imaging using PixiRad-2/PixieIII photon counting detector on a conventional laboratory X-ray micro-tomograph.
Authors: Granger R. , Salvo L. , Rolland du Roscoat S. , Lhuissier P. 
Published: February 2023

Abstract
Photon Counting Detectors (PCDs) open new opportunities in
X-ray imaging. Pixie III is a PCD using simultaneously two energy
thresholds. This enables to acquire images using two distinct energy
bins in a single exposure and allows to perform K-Edge Subtraction
(KES) imaging with laboratory sources. In that context, one has
however to deal with an energy bin optimization: narrow energy bins
lead to high KES signal at the expense of higher noise, while wider
energy bins lead to poor KES signal but better statistics. This work
presents a model that aims at finding the optimal energy thresholds
and source voltage in order to retrieve the best Contrast to Noise
Ratio (CNR) for a given sample. The model also optimizes the
parameters for conventional absorption modality and compares both
modalities. Since the input flux and the energy difference between
the thresholds influence image noise, this is included in the model
using phenomenological laws. The model is then compared to empirical
optimization by experimental screening of the parameters using model
materials composed of barium, iodine and water. Finally, it is
explained how to model the influence of sample composition on the
predicted CNR values.
Beyond river discharge gauging: hydrologic predictions using remote sensing alone
Authors: Yoon Hae Na , Marshall Lucy , Sharma Ashish 
Published: February 2023

Abstract
This study suggests a radical approach to hydrologic predictions in ungauged basins, addressing the long standing challenge of issuing predictions when in-situ river discharge does not exist. A simple but powerful rationale for measuring and modeling river discharge is proposed, using coupled advances in hydrologic modeling and satellite remote sensing. Our approach presents a Surrogate River discharge driven Model (SRM) that infers Surrogate River discharge (SR) from remotely sensed microwave signals with the ability to mimic river discharge in varying topographies and vegetation cover, which is then used to calibrate a hydrological model enabling physical realism in the resulting river discharge profile by adding an estimated mean of river discharge via the Budyko framework. The strength of SRM comes from the fact that it only uses remotely sensed data in prediction. The approach is demonstrated for 130 catchments in the Murray Darling Basin (MDB) in Australia, a region of high economic and environmental importance. The newly proposed SR (SRL, representing L-band microwave) boosts the Nash-Sutcliffe Efficiency (NSE) of modeled flow, showing a mean NSE of 0.54, with 70% of catchments exceeding NSE 0.4. We conclude that SRM effectively predicts high-flow and low-flow events related to flood and drought. Overall, this new approach will significantly improve catchment simulation capacity, enhancing water security and flood forecasting capability not only in the MDB but also worldwide.