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Globally, there has been a general increase of women in physics. However, they are still under-represented as compared to the other sciences. As to date, only three women have been awarded the Nobel Prize in Physics out of 51 female Nobel Laureates since 1901. The percentage of women laureates has roughly doubled in the 21st century. In Malaysia, national policies that aimed to have women holding at least 30% of decision-making roles by 2020 were put into place since 2011. This has been quite successful in increasing gender diversity in Malaysia. Furthermore, Malaysia's education system is different because of the secondary education system style of rote learning that could be better suited for females and the system is gender blind. Taking a case study of entrants in a Bachelor's degree programme in Physics in Universiti Malaya, the average gender parity index (GPI) over the past 5 years is 0.89. This is lower than the national GPI of 1.27-1.37 for Bachelor's degree entrants in Science, Technology, Engineering and Mathematics (STEM) in public universities. At the PhD level in STEM, the GPI drops to 0.77-0.95. The average GPI for faculty members in Department/School/Programme of Physics of 11 Malaysian universities is 0.80. [ABSTRACT FROM AUTHOR]

The KAGRA collaboration is a scientific organization for the gravitational-wave (GW) detections and GW astrophysics. It consists of more than 360 members from 14 different countries as of June 2019. Regardless the host institutions are the university of Tokyo, National Astronomical Observatory of Japan and KEK which are all in Japan, and regardless the experimental site is in Japan, there are many international members. However, in the collaboration, women and non-Japanese collaborators are still minorities. To accelerate the scientific efficiency, making a comfortable work environment for any members is a key. As a first step, we conducted an online demographic survey. In this article, the result of the survey and our efforts to make better collaboration will be shown. [ABSTRACT FROM AUTHOR]

The first synchrotron light source in Thailand was established in 1996, Siam Photon Source is operated and developed the capability of the facility to increase the energy up to 1.2 GeV by Synchrotron Light Research Institute (SLRI). Many users from both inside and outside the country come to use the synchrotron light which is increasing steadily. As a result, Siam Photon Source II at 3 GeV project is taken place in 2019. The Hard X-ray absorption spectroscopy has been planned to support which two consideration designs of the X-ray energy range are 2.4 – 40 keV at the first and 4 – 35 keV at the second. The scattering synchrotron radiation can occur from the optical components in the beamline. The radiation must be controlled to be safe for the utilization of synchrotron radiation in which the radiation shielding design is taken into account. This work aimed to compare the first and second HXAS beamline shielding designs to evaluate the dose distribution to prevent the radiation scattering. The dose calculation was performed by STAC 8 program, therefore, estimate the radiation dose level at the surface outside of the beamline both optic hutch and experimental hutch. The results of the two design indicated that dose distributions with the scattering angle were below the design criteria at 0.1 µSv/h. The optic hutch shielding wall for the first design is below the second design while the experimental hutch shielding wall for the first design is higher than the second design. [ABSTRACT FROM AUTHOR]

The Peer Instruction approach developed by Eric Mazur is often applied to a physics class. Reflection and discussion in this method is effective for students to engage deeply with the content during classes. However, some students may be silent during discussion time. In order to investigate a relationship between participation to discussion and learning outcomes, the volume of speaking voice for each student in Peer Instruction was measured in this study. Our study was used to investigate the introductory physics course at Hokkaido Information University. As a result, it was found that approximately 64% of participants in the class talked in discussion and the percentage of correct answers after discussion increased for those students, while the students in silence did not increase so much. This result supports quantitatively the effectiveness of Peer Instruction. However, the existence of silent students raise the problem of why they do not talk. Furthermore, it proposes a question of whether making such students talk is necessary or not. [ABSTRACT FROM AUTHOR]

We have conducted theoretical study on a production reaction 16 O (K − , p) K − 15 C which populates kaonic nuclei C K − 15 (=15N-K− bound system). The main purpose of this study is to deduce the kaon-nucleus interaction from the present existing and future experimental observations of kaon-nuclear production through (K−, p) reaction with different targets. Our analysis using 16O target is the first step for our upcoming systematic study by employing wide range of targets. We have considered two models, namely K−pp and Λ*p models in our analysis to determine the formation mechanism of kaonic nucleus and find out the differences between the two models. We have investigated the missing mass spectrum for the above (K−, p) reaction by using Green's function method. The interaction between K− and nucleus is taken to be Woods-Saxon potential. We have analyzed the characteristic of the spectrum by varying the potential strengths as well as scattering angles by using the above two models. It is observed that a large component of quasi free K− is compatible with the Λ*p model. [ABSTRACT FROM AUTHOR]

Printed circuit board (PCB) owns the most significant development in circuit packaging. It provides electrical connectivity for various electronic components, fixed in position surface-mounted by soldering. During high temperature reflow soldering process, there is a possibility of having mismatch of coefficients of thermal expansion (CTE) where PCB materials experience expansion in different dimensions. CTE mismatch leads to deformation of the board and package side. Solder balls experience cyclical stress from the warp, causing cracks in solders hence disjoint. In this study, the thermal induced warpage in multi-layer SSD PCB arrays are measured using Shadow Moiré method. During experiment, bottom part of the board may experience more heating than the top part of the board, which results in temperature difference between the top and bottom sides of PCB, ΔT. ΔT was controlled in Shadow Moiré by changing the heating powers (30%, 80%, and 100%) and by using different heating profiles. Finite element analysis (FEA) are carried out to determine the warpage of the PCB arrays. Simulation results are compared to the Shadow Moiré measurements. [ABSTRACT FROM AUTHOR]

We study a ferromagnetic instability in a single-band Hubbard model on the hypercubic lattice away from half filling. Using dynamical mean-field theory with the continuous-time quantum Monte Carlo simulations based on the segment algorithm, we calculate the magnetic susceptibility in the weak and strong coupling regions systematically. We then find how ferromagnetic fluctuations are enhanced when the interaction strength and density of holes are varied. The efficiency of the double flip updates in the Monte Carlo simulations is also addressed. [ABSTRACT FROM AUTHOR]

It is known that universe began with a hot big bang with radiation dominated era involving photons. For this reason, photons are studied at finite temperature. In order to determine thermal effects on photons, calculations of longitudinal photon self-energy are made within real time formalism in mixed space. [ABSTRACT FROM AUTHOR]

The primary target of ILC 250 is to precisely measure the coupling constants between the Higgs boson and other Standard Model particles. For this, we need to precisely calibrate the energy scales for various particles. In this paper, the necessary calibration methods using the e+e− → γZ process will be discussed. We will focus on the photon energy reconstruction methods and report the calibration precision. [ABSTRACT FROM AUTHOR]

Within the framework of Categorical Quantum Mechanics, it was found that orthogonal bases are subsumed by the so called classical structures. So, there must be classical structures which have the eigenbases of the Pauli X,Y and Z operators as their underlying bases. In this article, we propose a procedure for composing these classical structures on a single qubit which produces classical structures on multiple qubits. As a result, we can present orthogonal bases within a multiple qubit system as diagrams which makes explicit the entanglement structure of those bases. [ABSTRACT FROM AUTHOR]

In this paper we discuss the misconceptions detectable in Force Concept Inventory responses by analysing student selection of distractor items. We discuss the appearance of distinct, coherent, clusters of distractor items which appear in this data. Certain distractor items are structurally central in these groupings and sub-groups within these clusters may be interlinked by "connector" items. Our analysis suggests that these clusters represents a coherent, robust, non-Newtonian worldview. We further suggest that this worldview could be destabilised by correcting a small number of conceptual mistakes. [ABSTRACT FROM AUTHOR]

In this study, we investigate the Monopole-Antimonopole Pair (MAP) solution in the SU(2)×U(1) Weinberg- Salam theory with ¢-winding number, n = 3 for bifurcation phenomena. At n = 3, the 't Hooft-Polyakov monopole merges with antimonopole to form a vortex ring. Other than fundamental solution, two new bifurcating full vortex ring solution branches were found when Higgs coupling constant, λ reaches a critical value λc. The two new branches possess higher energies than the fundamental solutions. These solutions behave differently from the vortex ring configuration we studied in SU(2) Georgi-Glashow theory. We investigated on the total energy E, vortex ring diameter dρ, and magnetic dipole moment µm, for 0 ≤ λ ≤49. [ABSTRACT FROM AUTHOR]

In this work, we study the one plus half-monopole configuration in Weinberg-Salam model, covering ¢-winding number n=1. We observed that while the finite separation between the one-monopole and the half-monopole becomes larger as compared to the same configuration in Georgi-Glashow model, a flux tube is established, creating a bound-state of one-monopole and half-monopole in Weinberg-Salam model. There is no electromagnetic current loop circulating the pair of one-monopole and half-monopole, but the system possesses non-vanishing magnetic dipole moment. The non-Abelian gauge potential and the electromagnetic gauge potential are singular along the negative z-axis, but the total energy is finite. The solutions are investigated by fixing the Weinberg angle while varying the Higgs self-coupling constant and vice versa. It is shown that this configuration in Weinberg-Salam model possesses different behaviours than its counterpart in Georgi-Glashow model. [ABSTRACT FROM AUTHOR]

We have investigated theoretically the missing-mass spectral function of (π−, K+) reaction on 9Be target to populate ∑−pLi ∑-hypernucleus. If there is an appreciable amount of ∑N-ΛN coupling effect, this double charge exchange reaction would be a plausible way to populate neutron-rich Λ-hypernuclei. We have used Plane Wave Impulse Approximation Method together with ∑-nucleus Woods-Saxon potential. It is found that the strengths of V∑=−20 MeV and W∑=-3MeV give an observable narrow peak in the spectrum of ∑−9Li. To investigate the Λ-L coupling effect and ∑ mixing component Λ9He, we also studied the structure calculation of Λ9He by solving the coupled channel Schrodinger equation. Λ-∑ coherent coupling effect is 0.19 MeV and ∑ mixing probability is 0.2% in Λ9He. [ABSTRACT FROM AUTHOR]

We report an experimental and theoretical analysis of the phase switch from the zero voltage state to the finite voltage state of Bi2Sr2CaCu2Oy intrinsic Josephson junctions (IJJs). In the resistively and capacitively shunted junction (RCSJ) model for a single Josephson junction, the effect of thermal fluctuations is taken into account as two stochastic processes: the thermally activated (TA) escape process from a potential well and the phase retrapping (PR) process to the next potential well. The two different methods examined here are (i) the so-called TA+PR model, which considers only successive PR processes after the TA escape process and (ii) the Monte Carlo simulations, which numerically simulate the sequence of stochastic processes. The fitting of the experimental data based on those two methods indicate that the complex stochastic processes missing in the TA+PR model are needed to explain the switching current distribution at relatively high temperatures. Furthermore, we propose the multi- RCSJ model taking into account a layered crystal structure of IJJs, and demonstrate the validity through a detailed fitting with experimental data. [ABSTRACT FROM AUTHOR]

The Coulomb shift in the mirror systems of α +14C in 18O and α+14O in 18Ne is investigated by applying the orthogonality condition model (OCM). The result of OCM predicts the reduction of the excitation energies of the higher O+ states in the proton-rich nucleus of 18Ne in comparison to the energies in the neutron-rich 18O nucleus. This reduced excitation energy is similar to the phenomenon known as the Thomas-Ehrman shift, which means the lower shift in the excitation energy of the s-wave single particle orbit around the 16O core. [ABSTRACT FROM AUTHOR]

The chirality is the key for our world. In this talk with chiralities, I present a solution of the long standing gauge hierarchy problem with a hidden sector SU(5)' with representations 10 ¯ ⊕ 5 ¯ ⊕ 2 ⋅ 5. Sideway remarks are on NATURAL HILLTOP inflation and a bound on the QCD angle θ ¯ . [ABSTRACT FROM AUTHOR]

We investigate the gauge/gravity duality between the Ν = 6 mass-deformed ABJ theory with Uk(N+l)×U−k(N) gauge symmetry and 11-dimensional supergravity on LLM geometries with S O (2 , 1) × S O (4) / ℤ k × S O (4) / ℤ k isometry and the discrete torsion l. We obtain the vacuum expectation values (vevs) of chiral primary operators (CPOs) with conformal dimension one for the supersymmetric vacuum solusions in the mass-deformed ABJ (mABJ) theory, and compare it to dual quantities obtained by using the holographic method in 11-dimensional supergravity. In the large N limit, we show that the vevs are in exact agreement with the holographic quantities for all supersymmetric vacuum solutions. For LLM geometries with the discrete torsion, the holo-graphic results comprise 1 / N corrections. We also explore the effects of the orbifolding on the gauge/gravity duality dictionary and on the nature of the asymptotic limits of the LLM geometries. [ABSTRACT FROM AUTHOR]

In this paper, the double-Λ hypernuclei, H Λ Λ 6 e , H Λ Λ 5 e and H Λ Λ 5 e have been theoretically investigated to determine effective Λ-Λ interaction energies in double-Λ hypernuclei which is closely related to hyperon superfluidity in neutron stars. These double-Λ hypernuclei were considered as three-body cluster model; Λ-Λ-core nucleus. We constructed the free-space single-channel Λ-Λ interaction from Shinmura's multi-channel S=-2 potentials which are phase shift equivalent to Nijmegen soft core potentials. The interaction strength and range parameter are fitted with the most updated experimental data of Nagara event from E373 experiment. By using NSC97e potential, the effective Λ-Λ interaction energies are found to be 0.67 MeV, 0.88 MeV and 0.64 MeV for H Λ Λ 6 e , H Λ Λ 5 e and H Λ Λ 5 e respectively. The medium effects are not negligible in these double-Λ hypernuclei. [ABSTRACT FROM AUTHOR]

In this study we compared the fluorescence emission of algal, river water/wastewater, and oil samples using a pulsed LED light source and an Ocean Optics Xenon Arc Lamp source. Light-emitting diodes (LED) had become an important light source in the field of fluorescence spectroscopy and Lamp type LEDs are cheap and can provide a narrow source of wavelength as compared to the continuous Xenon Arc lamp source. However, it is sensitive to static electricity and electrical power. If the LED is operated in pulsed mode, it can provide stable high intensity at a longer time. For the experiment, the operating modes of the three pulsed LED are 20mW, 50 µs at 500 Hz. For the river water samples, the fluorescence emission showed significant results at 500-nm. At 685-nm emission wavelength of the algal samples, the pulsed LED signal showed a positive correlation with the Xenon lamp. However, peak shifting was observed for the oil samples due to low excitation intensity observed. [ABSTRACT FROM AUTHOR]

A technique to produce spin orientation in RI beams was developed for measurements of nuclear moments. The present scheme of two-step reaction realized highly spin-aligned RI beams for a wide range of exotic nuclei. Recently the two-step reaction scheme was applied to the magnetic moment measurement of an isomeric state of a neutron-rich nucleus 75Cu, where its magnetic moment was determined for the first time owing to a 30%-spin-aligned beam. A further perspective of the nuclear moment measurements employing the present scheme is expected. [ABSTRACT FROM AUTHOR]

We have studied the photoproduction of Λ(1405) from the CLAS Collaboration with a chiral dynamics model. The reaction γ + p → K + (π ∑) 0 was conducted for the wide range of photon energies 1.95

Industrial computed tomography provides a means to non-destructively examine defects in concrete structures. CT images were obtained from gamma ray scans of several rebar imbedded concrete samples as well as scans of rectangular concrete pillars. The CT scanner consists of a clamped on mechanical gantry, a 1" x 1" NaI(Tl) scintillation detector, 0.4GBq Ba-133 source, 15mm x 5mm lead collimators and Ludlum scaler ratemeter. The purpose of this work was to provide baseline image structural information to detect anomalies and to check internal structural deviation in concrete-based pillars. Among possible causes of defects are poor concrete compaction, rebar congestion, and insufficient concrete strength. It is suggested that rich information from 2D CT images could help the engineer make the right decisions on the state of deterioration of building pillars. The images also provide direct evidence of presence of void, and rebar placement. Further works using the portable gamma ray CT scanner are expected to be used in non-invasive inspection for building restoration. [ABSTRACT FROM AUTHOR]

The beta-detected nuclear magnetic resonance (β -NMR) technique is a novel method that obtains depth-resolved information on samples by observing the asymmetric beta decay of nuclear probes. Although the beta-detected NMR has several advantages over the conventional NMR techniques, the number of user facilities in the world is severely limited. At the site of Korea Multi-purpose Accelerator Complex (KOMAC), we initiated a research project to develop a radioactive ion (RI) beam facility dedicated for the future beta-detected NMR facility at KOMAC based on a 100-MeV proton linear accelerator. In this endeavour, we developed a prototype of a target-ion-source (TIS) composed of low-Z production targets, target container, target heater, high-current feed through, and hot surface ion source. In recent on-line experiments, we have demonstrated that a Li-8 beam of the order of 106 pps could be extracted with the prototype design of the TIS. Here, we present the recent progress of the RI beam development study. [ABSTRACT FROM AUTHOR]

Systematic and anomalous trends in fragment mass and TKE (total kinetic energy) distributions are investigated in terms of the 4D Langevin model developed at Tokyo Tech. We have found that correlated transitions in symmetric components and dominant modes (symmetric v.s. asymmetric) can explain the prominent systematic and anomalous features of fission observables. We have also elucidated that interplay between spherical and deformed magicity at A=132 and A=142 to 144 is important in both observables. [ABSTRACT FROM AUTHOR]

Research on nuclear forces between the nucleon and the hyperon has been studied mainly on experiments on measuring the binding energy of hypernuclei. We thought that we understood the hyperon-nucleon force because theoretical models based on experimental data could reproduce many hypernuclear data. However, for recent H Λ 4 (pnnΛ) and He Λ 4 (ppnΛ) data, the theoretical Λ Λ model does not reproduce the binding energies of the ground and excited states. In these two hypernuclei, only p and n are replaced by one, and the expected binding energy is simply expected to be dominant due to the effect of Coulomb force. Experimental data show differences that cannot be explained by the theoretical model and the problem called charge symmetry breaking (CSB) in ΛN interaction. The key to solving the problem is to measure Λn forces that have not been measured with good accuracy. To measure the force between Λ and n, which cannot perform direct scattering experiments, we are preparing an experiment to measure the K+ production cross-section modified by the Λn final state interaction in the γd→K+Λn reaction. The experiment will be performed with a real photon beamline generated from a 1.3 GeV electron synchrotron in Research Center for Electron Photon Science (ELPH), Tohoku University. In the beamline, we have been conducting K0Λ production experiments using the NKS2 spectrometer. We are developing a new detector to measure K+, and report on it. [ABSTRACT FROM AUTHOR]