Phenomenology of NMSSM in TeV scale mirage mediation

We study the next-to-minimal supersymmetric standard model (NMSSM) with the TeV scale mirage mediation, which is known as a solution for the little hierarchy problem in supersymmetry. Our previous study showed that 125 GeV Higgs boson is realized with O(10) % fine-tuning for 1.5 TeV gluino (1 TeV stop) mass. The $\mu$ term could be as large as 500 GeV without sacrificing the fine-tuning thanks to a cancellation mechanism. The singlet-doublet mixing is suppressed by $\tan\beta$. In this paper, we further extend this analysis. We argue that approximate scale symmetries play a role behind the suppression of the singlet-doublet mixing. They reduce the mixing matrix to a simple form that is useful to understand the results of the numerical analysis. We perform a comprehensive analysis of the fine-tuning including the singlet sector by introducing a simple formula for the fine-tuning measure. This shows that the singlet mass of the least fine-tuning is favored by the LEP anomaly for moderate $\tan\beta$. We also discuss prospects for the precision measurements of the Higgs couplings at LHC and ILC and direct/indirect dark matter searches in the model.Comment: 47 pages, 46 figures, version accepted by JHE

Anisotropy of upper critical fields and interface superconductivity in FeSe/SrTiO3 grown by PLD

In this study, we grow FeSe/SrTiO$_{3}$ with thicknesses of 4-19 nm using pulsed laser deposition and investigate their magneto-transport properties. The thinnest film (4 nm) exhibit negative Hall effect, indicating electron transfer into FeSe from the SrTiO$_{3}$ substrate. This is in agreement with reports on ultrathin FeSe/SrTiO$_{3}$ grown by molecular beam epitaxy. The upper critical field is found to exhibit large anisotropy ($\gamma >$ 11.9), estimated from the data near the transition temperature ($T_{\mathrm{c}}$). In particular, the estimated coherence lengths in the perpendicular direction are 0.15-0.27 nm, which are smaller than the c-axis length of FeSe, and are found to be almost independent of the total thicknesses of the films. These results indicate that superconductivity is confined at the interface of FeSe/SrTiO$_{3}$.Comment: 5pages, 3figure

Anisotropic interpolation error estimates using a new geometric parameter

We present precise anisotropic interpolation error estimates for smooth functions using a new geometric parameter and derive inverse inequalities on anisotropic meshes. In our theory, the interpolation error is bounded in terms of the diameter of a simplex and the geometric parameter. Imposing additional assumptions makes it possible to obtain anisotropic error estimates. This paper also includes corrections to an error in Theorem 2 of our previous paper, "General theory of interpolation error estimates on anisotropic meshes" (Japan Journal of Industrial and Applied Mathematics, 38 (2021) 163-191).Comment: 36 pages, 12 figure

Study of Gasoline Pre-chamber combustion at Lean Operation

Regulations and other demands to enhance automobile fuel economy are growing increasingly strict to reduce CO2 as a measure to address the issues of global warming. The goal of this study was to enhance the fuel economy in high-load operation of a gasoline engine for hybrid vehicles, which is a useful means of addressing this issue. Technology for achieving lean combustion in high-load operation was studied to realize higher brake thermal efficiency by increasing the ratio of specific heat compared to theoretical air-fuel ratio (stoichiometric) EGR combustion. Issues for applying lean combustion to high-load operation include 1) the increased oxygen molarity results in increased knocking tendency compared to stoichiometric EGR combustion, and 2) increased leanness results in greater combustion variation due to the ignition delay period and the delayed second half of the combustion period. In order to solve these issues at lean operation, several combustion methods are examined on test bench. In this test study, Pre-chamber stratified combustion has an advantage of lean operation performance. Ignitability and high-speed combustion period of pre-chamber combustion was secured by setting the ignition areas inside the pre-chamber to the rich side relative to the total air-fuel ratio (A/F). NOx emissions are an issue for stratified combustion, but NOx emissions can be reduced by setting the pre-chamber A/F to approximately 23 and by making the pre-chamber volume sufficiently small compared to the main combustion chamber volume. Tests were performed using a single-cylinder engine to determine the pre-chamber volume and the diameter and number of jet nozzles. The pre-chamber volume and the diameter and number of jet nozzles were set under the restriction of dP/dθ, which is the index of combustion noise, as the target value or less. This specification realized minimum advance for the best torque (MBT) operation with an A/F of 35 at 2000 rpm, IMEP 810 kPa. The heat release characteristics of prechamber combustion shows that unlike the typical combustion pattern using strong flow, the heat release characteristics have two peaks. The first peak is the flame state wherein the jet flame has spread throughout the entire combustion chamber. This shows that the amount of heat released inside the pre-chamber enabled the flame jets from the jet nozzles to spread within the main combustion chamber. The second peak is the state wherein the unburned gas around the spread jet flames is all burning instantaneously. This combustion state results in rapid and stable combustion during the second half of combustion. This combustion characteristic realized MBT lean combustion in high-load operation. The balance between the compression ratio and the surface volume ratio (S/V) was reviewed to counter the drop in efficiency due to the increased S/V as a result of adding a pre-chamber, and this enabled MBT operation at 2000 rpm, IMEP 870 kPa, A/F 35 with an IMEP variation rate of 1.2 %, a main combustion period of 18 deg, and NOx of 30 ppm. Together with the effects of heat insulation coating inside the pre-chamber, this enhanced the brake thermal efficiency by +2 point compared to stoichiometric EGR combustion

Salted Radish Root Biology during Food Processing

White radish root (daikon) is an important vegetable in Japanese food culture and has spawned the development of various cooking and processing methods. takuan-zuke is the major processed food derived from daikon. Takuan-zuke is prepared by the dehydration of the root using a salt-press or a weighted stone, or by sun-drying, followed by salt-aging using salt or salted rice bran. The color of takuan-zuke changes to yellow during salt-aging. We determined the effects of dehydration and salt-aging on the metabolism of daikon using takuan-zuke. In the yellowing reaction, the generation of daikon isothiocyanate was significant, requiring a temperature of ≥10°C and pH ≥5. The color change of the sun-dried takuan-zuke was the most significant. Moreover, we investigated the nutritional characteristics of takuan-zuke. In the sun-dried daikon, metabolism progressed for 3 weeks during drying, with increase in the concentrations of γ-aminobutyric acid (GABA) and proline as well as drying stress metabolites. In the salt-pressed daikon, GABA concentrations temporarily increased due to osmotic stress but then decreased on metabolic inhibition by salt permeation. In addition, no change in the concentration of proline was observed under salt-press conditions. The results showed a marked difference between the stress response of the living and processed root