"Dark matter is one of the mystery of modern particle physics and cosmology. We have studied the method to search for dark matter using ultracold atoms. Recently, we developed the Mx magnetometer to estimate the magnetic field around the trap region. In this poster, we report our current status and experimental results."
"The fundamental parity violation caused by the hadronic weak interaction is enhanced by up to 10^6 times in neutron absorption reactions of 139La, 131Xe, 117Sn, and other nuclei. This enhancement can be explained by the mixing between s-wave and p-wave amplitudes of the compound nuclear state (s-p mixing model). Similarly, T-violation can also be enhanced in these systems through the same...
"Axion and Dark Photon (DP) have been considered as well-motivated dark matter candidates. Axion was originally introduced as the solution to the Strong CP problem, while DP is a massive vector particle predicted by any extension of the Standard Model. Both particles should experience coupling or mixing with normal photons, this characteristic renders them viable for direct dark matter...
"The parity-violating energy difference (PVED) between the enantiomers of a chiral molecule is caused by the Z boson exchange between electrons and nucleons. PVED is proportional to the difference in electron chirality density between the enantiomers at the nuclear positions. PVED has not yet been observed experimentally.
The integral value of the electron chirality density generally has a...
"If cold dark matter is light pseudo scalar particles, herein referred to as Axion-Like Particles (ALPs), it rotates the polarization of linearly polarized light. Several experimental schemes using an optical cavity have been proposed to detect this effect. Birefringence at the mirrors, however, would degrade the sensitivity. We have studied the effect of the birefringence on the sensitivity...
"Our purpose is precision measurement of the 1S-2S energy interval in Muonium, which is an exotic hydrogen-like atom consists of a positive muon and an electron. This purely leptonic system enables a precise calculation of the energy interval with the Standard Model without any concerns of the uncertainty from the charge radius of the nucleus, unlike the hydrogen atom. This advantage motivates...
"Chiral symmetry is thought to be partially restored in the finite density such as nucleus thus, quark condensation should be decreased. To investigate wether the chiral symmetry is surly restored and how much of the chiral symmetry will be restored, embedding hadrons in the nucleus is effective methods. As systematic studies of deeply bound pionic atoms and the low-energy π−-nucleus elastic...
"Nuclear clocks based on the ultra-low isomeric state of thorium-229 are expected as the next-generation clocks. Solid-state nuclear clocks in which thorium-229 nuclei are doped in crystals excite a large number of nuclei simultaneously. Toward the development of solid-state nuclear clocks, direct excitation experiments to the isomeric state using thorium-229 doped crystals are currently being...
"ADC is commonly used in the nuclear and elementary particle fields as a method of measuring electric charge.
The conventional method for obtaining charge information is to digitize the analog signal from the detector by integrating the electric charge.
Therefore, existing data acquisition systems needs trigger system, which causes a dead time, as well as a delay of the analog signal by...
"The first excited state of the Th-229 nucleus has an exceptionally low energy of 8 eV, with laser excitability, and is an isomer state with a lifetime of about 10^3 seconds. As such, it is expected to be the only level that can be applied to nuclear clocks. Nuclear clocks are considered to achieve higher accuracy than atomic clocks and are expected to be used to explore physics beyond the...
"To evaluate frequency shifts including isotope shifts, we are developing a second ion trap system for ytterbium ions with three dimensional cooling. We will present a current status of the development."
"The Th-229 nucleus possesses the exceptionally low-energy first excited state (isomeric state) of approximately 8 eV, making it the only nucleus capable of being excited by lasers, and thus, it is expected to serve as a candidate for a nuclear clock. Last year, vacuum ultraviolet light with a wavelength of about 150 nm by the de-excitation from the isomeric state was observed for the first...
