Seikei University
We performed a precise calculation of physical quantities related to the axial structure of the nucleon using 2+1 flavor lattice QCD gauge configuration (PACS10 configuration) generated at the physical point with lattice volume larger than (10  fm)4(10\;{\mathrm{fm}})^4 by the PACS Collaboration. The nucleon matrix element of the axial-vector current has two types of the nucleon form factors, the axial-vector (FAF_A) form factor and the induced pseudoscalar (FPF_P) form factor. Recently lattice QCD simulations have succeeded in reproducing the experimental value of the axial-vector coupling, gAg_A, determined from FA(q2)F_A(q^2) at zero momentum transfer q2=0q^2=0, at a percent level of statistical accuracy. However, the FPF_P form factor so far has not reproduced the experimental values well due to strong πN\pi N excited-state contamination. Therefore, we proposed a simple subtraction method for removing the so-called leading πN\pi N-state contribution, and succeeded in reproducing the values obtained by two experiments of muon capture on the proton and pion electro-production for FP(q2)F_P(q^2). The novel approach can also be applied to the nucleon pseudoscalar matrix element to determine the pseudoscalar (GPG_P) form factor with the help of the axial Ward-Takahashi identity. The resulting form factors, FP(q2)F_P(q^2) and GP(q2)G_P(q^2), are in good agreement with the prediction of the pion-pole dominance model. In the new analysis, the induced pseudoscalar coupling gPg_P^\ast and the pion-nucleon coupling gπNNg_{\pi NN} can be evaluated with a few percent accuracy including systematic uncertainties using existing data calculated at two lattice spacings.
We consider the Courant-Hilbert (CH) construction of integrable deformations of a two-dimensional principal chiral model (2D PCM) in the context of the four-dimensional Chern-Simons (4D CS) theory. According to this construction, an integrable deformation of 2D PCM is characterized by a boundary function. As a result, the master formula obtained from the 4D CS theory should be corrected by the trace of the energy-momentum tensor so as to support the CH construction. We present some examples of deformation including the TTˉT\bar{T}-deformation, the root TTˉT\bar{T}-deformation, the two-parameter mixed deformation, and a logarithmic deformation. Finally, we discuss some generalizations and potential applications of this CH construction.
The first comprehensive calculation of the nucleon D-term employs a holographic QCD approach based on string theory, yielding a value of approximately -0.140  0.022. This result emerges from a delicate cancellation between positive and negative contributions from different meson sectors, offering insights into the internal mechanical properties of nucleons and providing a benchmark for future experimental measurements.
Researchers from Seikei University and KEK extended the GRACE automatic calculation system to include the Georgi-Machacek model, enabling automated computations for its complex phenomenology. They then utilized this enhanced tool to calculate production cross sections for the model's distinctive 5-plet Higgs bosons at future 0.5 TeV e+e- and e-e- colliders, demonstrating that e-e- colliders offer superior discovery potential and unique characteristic cross-section ratios for doubly-charged Higgs bosons.
We present a short summary for the calculations of the nucleon isovector\textit{isovector} form factors, which are relevant to improving the accuracy of the current neutrino oscillation experiments. The calculations are carried out with two of three sets of the 2+12+1 flavor lattice QCD configurations generated at the physical point in large spatial volumes by the PACS Collaboration. The two gauge configurations are generated with the six stout-smeared O(a)O(a) improved Wilson quark action and Iwasaki gauge action at the lattice spacing of 0.090.09 fm and 0.060.06 fm. We summarize the results for three form factors as well as the nucleon axial-vector (gAg_A), induced pseudoscalar (gPg_P^*) and pion-nucleon (gπNNg_{\pi NN}) couplings. Although our couplings agree with the experimental data, a firm conclusion should be drawn only after a continuum limit extrapolation is taken. We investigate the partially conserved axial-vector current (PCAC) relation in the context of the nucleon correlation functions. The low-energy relations arising from the PCAC relation can be used to verify whether the lattice QCD data correctly reproduce the physics in the continuum within the statistical accuracy. It is demonstrated that our new analysis\textit{new analysis} reduces the systematic uncertainty for the induced pseudoscalar and pseudoscalar form factors to a greater extent than the traditional analysis\textit{traditional analysis}, and the results offer a theoretical insight into the pion-pole dominance model. Finally, we examine the applicable q2q^2 region for the low-energy relations.
We elucidate the relation between Painlev\'e equations and four-dimensional rank one N=2{\cal N= 2} theories by identifying the connection associated to Painlev\'e isomonodromic problems with the oper limit of the flat connection of the Hitchin system associated to gauge theories and by studying the corresponding renormalisation group flow. Based on this correspondence we provide long-distance expansions at various canonical rays for all Painlev\'e functions in terms of magnetic and dyonic Nekrasov partition functions for N=2{\cal N= 2} SQCD and Argyres-Douglas theories at self-dual Omega background ϵ1+ϵ2=0\epsilon_1+\epsilon_2= 0, or equivalently in terms of c=1c= 1 irregular conformal blocks.
We study the double Higgs boson production processes e+ehhffˉe^+e^- \to hh f\bar{f} (ftf\neq t) with hh being the 125 GeV Higgs boson in the two-Higgs-doublet model with a softly-broken Z2Z_2 symmetry. The cross section can be significantly enhanced, typically a few hundreds percent, as compared to the standard model prediction due to resonant effects of heavy neutral Higgs bosons, which becomes important in the case without the alignment limit. We find a strong correlation between the enhancement factor of the cross section and the scaling factor of the hffˉhf\bar{f} couplings under constraints from perturbative unitarity, vacuum stability and current experimental data at the LHC as well as the electroweak precision data.
We present new measurements of the vertical density profile of the Earth's atmosphere at altitudes between 70 and 200 km, based on Earth occultations of the Crab Nebula observed with the X-ray Imaging Spectrometer onboard Suzaku and the Hard X-ray Imager onboard Hitomi. X-ray spectral variation due to the atmospheric absorption is used to derive tangential column densities of the absorbing species, i.e., N and O including atoms and molecules, along the line of sight. The tangential column densities are then inverted to obtain the atmospheric number density. The data from 219 occultation scans at low latitudes in both hemispheres from September 15, 2005 to March 26, 2016 are analyzed to generate a single, highly-averaged (in both space and time) vertical density profile. The density profile is in good agreement with the NRLMSISE-00 model, except for the altitude range of 70-110 km, where the measured density is about 50% smaller than the model. Such a deviation is consistent with the recent measurement with the SABER aboard the TIMED satellite (Cheng et al. 2020). Given that the NRLMSISE-00 model was constructed some time ago, the density decline could be due to the radiative cooling/contracting of the upper atmosphere as a result of greenhouse warming in the troposphere. However, we cannot rule out a possibility that the NRL model is simply imperfect in this region. We also present future prospects for the upcoming Japan-US X-ray astronomy satellite, XRISM, which will allow us to measure atmospheric composition with unprecedented spectral resolution of dE ~ 5 eV in 0.3-12 keV.
A graph is reconstructible if it is determined up to isomorphism by the multiset of its proper induced subgraphs. The reconstruction conjecture postulates that every graph of order at least 3 is reconstructible. We show that interval graphs with at least three vertices are reconstructible. For this purpose we develop a technique to handle separations in the context of reconstruction. This resolves a major roadblock to using graph structure theory in the context of reconstruction. To apply our novel technique, we also develop a resilient combinatorial structure theory for interval graphs. A consequence of our result is that interval graphs can be reconstructed in polynomial time.
We have developed the system for the automatic computation of cross-sections, {\tt GRACE/SUSY}, including the one-loop calculations for processes of the minimal supersymmetric extension of the the standard model. For an application, we investigate the pair-production of the heavy chargino in electron-positron collisions.
The primary goal of Motivational Interviewing (MI) is to help clients build their own motivation for behavioral change. To support this in dialogue systems, it is essential to guide large language models (LLMs) to generate counselor responses aligned with MI principles. By employing a schema-guided approach, this study proposes a method for updating multi-frame dialogue states and a strategy decision mechanism that dynamically determines the response focus in a manner grounded in MI principles. The proposed method was implemented in a dialogue system and evaluated through a user study. Results showed that the proposed system successfully generated MI-favorable responses and effectively encouraged the user's (client's) deliberation by asking eliciting questions.
Cloud computing is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources. To provide cloud computing services economically, it is important to optimize resource allocation under the assumption that the required resource can be taken from a shared resource pool. In addition, to be able to provide processing ability and storage capacity, it is necessary to allocate bandwidth to access them at the same time. This paper proposes an optimal resource allocation method for cloud computing environments. First, this paper develops a resource allocation model of cloud computing environments, assuming both processing ability and bandwidth are allocated simultaneously to each service request and rented out on an hourly basis. The allocated resources are dedicated to each service request. Next, this paper proposes an optimal joint multiple resource allocation method, based on the above resource allocation model. It is demonstrated by simulation evaluation that the proposed method can reduce the request loss probability and as a result, reduce the total resource required, compared with the conventional allocation method. Then, this paper defines basic principles and a measure for achieving fair resource allocation among multiple users in a cloud computing environment, and proposes a fair joint multiple resource allocation method. It is demonstrated by simulation evaluations that the proposed method enables the fair resource allocation among multiple users without a large decline in resource efficiency. Keywords: Cloud computing, joint multiple resource allocation, fairness
Diffractive dijet production at the electron-ion collider (EIC) has been proposed to study the gluon Wigner distribution at small-xx. We investigate the soft gluon radiation associated with the final state jets and an all order resummation formula is derived. We show that the soft gluon resummation plays an important role to describe E791 data on π\pi-induced diffractive dijet production at Fermilab. Predictions for the EIC are presented, and we emphasize that the soft gluon resummation is an important aspect to explore the nucleon/nucleus tomography through these processes.
Results are presented for the medium-induced, soft coherent radiation spectrum for all 222\to 2 partonic channels in QCD, at leading-order in αs\alpha_s but beyond leading logarithmic accuracy. The general formula is valid in the full kinematic range of the underlying process, and reduces to previous results in special cases. The soft gluon radiation spectrum is expressed in terms of the color density matrix specific to each channel, quantifying the entanglement between the color components of the 222 \to 2 production amplitude. Beyond the leading logarithm, the spectrum depends explicitly on the off-diagonal elements of this matrix, owing to the soft gluon's ability to probe the internal color structure of the parton pair.
We report on recent progress on the splitting functions for the evolution of parton distributions and related quantities, the (lightlike) cusp anomalous dimensions, in perturbative QCD. New results are presented for the four-loop (next-to-next-to-next-to-leading order, N^3LO) contributions to the flavour-singlet splitting functions and the gluon cusp anomalous dimension. We present first results, the moments N=2 and N=3, for the five-loop (N^4LO) non-singlet splitting functions.
We have developed the system for the automatic computation of cross-sections, {\tt GRACE/SUSY}, including the one-loop calculations for processes of the minimal supersymmetric extension of the the standard model. For an application, we investigate the process e+eZ0h0e^+ e^- \to Z^0 h^0 .
We introduce a new method to treat Majorana fermions and interactions with fermion-number violation on the GRACE system which has been developed for the automatic computation of the matrix elements for the processes of the standard model. Thus we have constructed a system for the automatic computation of cross-sections for the processes of the minimal SUSY standard model (MSSM).
We introduce a new method to treat Majorana fermions on the GRACE system which has been developed for the computation of the matrix elements for the processes of the standard model. In the standard model, we already have such particles as Dirac fermions, gauge bosons and scalar bosons in the system. On the other hand, in the SUSY models there are Majorana fermions. In the first instance, we have constructed a system for the automatic computation of cross-sections for the processes of the SUSY QED. It is remarkable that our system is also applicable to another model including Majorana fermions (e.g. MSSM) once the definition of the model file is given.
The paper computes the lowest four even Mellin moments of the four-loop flavour-singlet splitting functions in Quantum Chromodynamics (QCD), providing essential theoretical input for N³LO precision calculations in high-energy physics. This calculation reveals that the N³LO corrections are small, typically less than 1% relative to NLO, and substantially reduce the renormalization scale dependence of parton distribution function evolution to about 1%.
We present the first principle calculations of the electrical properties of graphene sheet/h-BN heterojunction(GS/h-BN) and 11-armchair graphene nanoribbon heterojunction(11-AGNR/h-BN), which were carried out using the density functional theory(DFT) method and the non-equilibrium Green's function(NEGF) technique. Since 11-AGNR belongs to the conductive (3n-1)-family of AGNR, both are metallic nanomaterials with two transverse arrays of h-BN, which is a wide-gap semi-conductor. The two h-BN arrays act as double barriers. The transmission functions(TF) and I-V characteristics of GS/h-BN and 11-AGNR/h-BN are calculated by DFT and NEGF, and they show that quantum double barrier tunneling occurs. The TF becomes very spiky in both materials, and it leads to step-wise I-V characteristics rather than negative resistance, which is the typical behavior of double barriers in semiconductors.
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