arXiv subjects

Jiro Murata

Publications and source records attributed to Jiro Murata.

5 recordsLinked to original sources

arXiv2026

Short-Range Tests of the Gravitational Inverse-Square Law

Experimental constraints on the gravitational inverse-square law at short range are presented, employing a consistent formalism across a wide range of length scales. We provide comprehensive updates incorporating new experimental data from the past decade - spanning tabletop forces, Casimir measurements, slow neutron scattering, and collider searches - building upon our previous review. This work facilitates the direct comparison of experimental results with theoretical models that extend general relativity. Furthermore, a comparison between various model parametrizations, including extra-dimensional models, is introduced. Finally, results from tabletop experiments are compared with those from high-energy collider experiments for both Yukawa and power-law potentials.

gr-qc↗

arXiv2024

Current-readout technique for ultra-high-rate experiments

This study developed a new current-readout technique capable of handling measurements with high count rates reaching 1 Gcps. By directly capturing the output current of a photomultiplier as a digitized waveform, we estimated event rates, overcoming the limitations imposed by pulse pileup constraints and deadtimes. This innovative method was applied to a muon spin rotation/relaxation/resonance experiment at the Japan Proton Accelerator Research Complex, demonstrating its anticipated performance. Furthermore, we explored methods for estimating statistical uncertainty and investigated potential applications in analog-logic OR/AND gates. Overall, our findings reveal that the developed technique opens up avenues for the development of future non-binary logic circuits operating based on n-adic numbers.

physics.ins-det↗

arXiv2022

Study of curling mechanism by precision kinematic measurements of curling stone's motion

Why do curling stones curl? That is a question physicists are often asked, yet no answer has been established. Stones rotating clockwise curl right, contrary to our naive expectations. After a century of debate between contradicting hypotheses, this paper provides the answer based on experimental evidence. A digital image analysis technique was used to perform precision kinematic measurements of a curling stone's motion to identify the curling mechanism. We observed a significant left-right asymmetric friction due to velocity dependence on the friction constant. Combined with the discrete point-like nature of the friction between ice and stone, swinging around slow-side friction points has been concluded as the dominant origin of the curling. Many new angular momentum transfer phenomena have been found, supporting this conclusion.

physics.pop-ph↗

arXiv2014

Review of short-range gravity experiments in the LHC era

This document briefly reviews recent short-range gravity experiments that were performed at below laboratory scales to test the Newtonian inverse square law of gravity. To compare sensitivities of these measurements, estimates using the conventional Yukawa parametrization are introduced. Since these experiments were triggered by the prediction of the large extra-dimension model, experiments performed at different length scales are compared with this prediction. In this paper, a direct comparison between laboratory-scale experiments and the LHC results is presented for the first time. A laboratory experiment is shown to determine the best limit at $M_D > 4.6 \;\rm{TeV}$ and $λ<23 \;μ\rm{m}$. In addition, new analysis results are described for atomic systems used as gravitational microlaboratories.

hep-ex↗

arXiv2001

Beyond the standard model physics at RHIC in polarized pp collision

A polarized hadron collider experiment must have a great discovery potential for a search of physics beyond the standard model. Experimental data of various symmetry tests at RHIC are going to be obtained within a few years. The author developed a simulation tool, studying a sensitivity of hunting contact interaction at RHIC by measuring parity violating spin asymmetries.

hep-ex↗