15085801
Search for a kaonic nuclear state via 4He(K−, N) reaction at rest
Very recently, we have performed a couple of experiments, KEK PS-E549/E570, for the detailed study of the strange tribaryon S 0(3115) obtained in KEK PS-E471. These experiments were performed to accumulate much higher statistics with improved experimental apparatus especially for the better proton spectroscopy of the 4He(stopped K −, N) reaction. In contrast to the previous proton spectrum, no narrow (∼ 20 MeV) peak structure was found either in the inclusive 4He(stopped K −, p) or in the semi-inclusive 4He(stopped K −, pX ±) reaction channel, which is equivalent to the previous E471 event trigger condition. Detailed analysis of the present data and simulation shows that the peak, corresponding to S 0(3115), has been an experimental artifact. Present analysis does not exclude the possible existence of a much wider structure. To be sensitive to such structure and for better understanding of the non-mesonic K − absorption reaction channel, detailed analysis of the data is in progress.
124123633
SEARCH FOR LORENTZ AND CPT VIOLATION EFFECTS IN MUON SPIN PRECESSION
117791711
Radioactive Muonic Atom Studies with Intense Muon Beams
New intense muon beams with flux several orders of magnitude higher than at present muon facilities would allow many novel experimental studies that were until now statistically not feasible. The investigation of the nuclear properties of short‐lived nuclei using muonic atom spectroscopy would become possible. In this paper, the recent progress of a feasibility study at RIKEN‐RAL muon facility using the cold hydrogen film method to produce radioactive muonic atoms is being reported. The first experimental results have just been obtained with stable argon ions implanted in solid deuterium films.
122600834
Muon catalyzed fusion experiments on muonic deuterium atom deceleration in thin solid deuterium films
Abstract Muon catalyzed fusion was investigated in a series of thin solid deuterium films by detecting protons from dd fusion. Two different contributions to the total fusion yield resulting from dμ atoms emitted from a primary hydrogen layer and from incident muons directly stopped in the deuterium film itself were observed. The thickness dependence of the fusion yield suggested the importance of molecular effects in dμ elastic scattering in D 2 .
124815658
Measure of the spatial size for the monopole excitation in proton scattering
121882195
Discovery of the repulsive energy shift of the kaonic hydrogen 1s state
Abstract The aim in this manuscript is to clarify the progress in understanding the nature of the K ¯ N interaction at the lowest energy, given by the recent kaonic hydrogen X-ray experiment at KEK [1]. We have observed a clear spectrum showing the kaonic hydrogen K α line, for the first time. The analysis gives the repulsive energy shift to be Δ E (1 s ) = −323 ± 63(statistical) ± 11 (systematic) eV and the energy width to be Λ(1 s ) = 407 ± 208 ± 100 eV. This result is consistent with analyses of the previous low-energy scattering data and resolves the long-standing kaonic hydrogen puzzle.
123052618
Instability of the Chiral Quantum Baryon
The chiral quantum baryon which is stabilised by the quantum effect is discussed within the nonlinear σ-model with the pion mass term. It is shown that the quantum baryon does not exist mathematically even if the pion mass term is taken into account
6081502
Mass spectra and decay widths of hadrons in the relativistic string model
A relativistic string model for hadrons is presented. The center-of-mass motion is separated correctly. The vibrational and rotational motions of the string are solved by using the WKB approximation. Moreover, their decay widths are calculated by taking into account the pair creation of quarks inside the string. Both the mass spectra and the decay widths are reproduced fairly well in comparison with experimental data.
15071400
LCD ROOT simulation and analysis tools
The North American Linear Collider Detector group has developed a simulation program package based on the ROOT system. The package consists of Fast simulation, the reconstruction of the Full simulated data, and physics analysis utilities.
122800760
Phase Transition of Quark Matter at High Density.
54880563
Design and Status of the SuperKEKB Accelerator Control Network System
We have upgraded the accelerator control network system for SuperKEKB, the next generation B-factory experiment in Japan. The designed network system has the higher performance based on the wider bandwidth data transfer, and more reliable and redundant configuration. For the SuperKEKB beamline construction and accelerator components maintenance, we have installed the new wireless network system consists with the Leaky Coaxial (LCX) cable antennas and collinear antennas into the 3 km circumference accelerator tunnel. In this paper, we describe the design and current status of the SuperKEKB accelerator control network system.