5 papers
Divalent lanthanoid ions in crystals for neutrino mass spectroscopy
H. Hara, N. Sasao, M. Yoshimura
Electron spin flip in atoms or ions can cause neutrino pair emission, which provides a method to explore still unknown important neutrino properties by measuring spectrum of emitte…
Raman stimulated neutrino pair emission
H. Hara, M. Yoshimura
A new scheme using macroscopic coherence is proposed from a theoretical point to experimentally determine the neutrino mass matrix, in particular the absolute value of neutrino mas…
X-ray pumping of the Th-229 nuclear clock isomer
Takahiko Masuda, Akihiro Yoshimi, Akira Fujieda +27
Thorium-229 is a unique case in nuclear physics: it presents a metastable first excited state Th-229m, just a few electronvolts above the nuclear ground state. This so-called isome…
Geometry-dependent spectra and coherent-transient measurement of nearly degenerate four-wave mixing using two-photon resonance
Hideaki Hara, Yuki Miyamoto, Takahiro Hiraki +7
We study nearly degenerate four-wave mixing using a two-photon-allowed vibrational transition of parahydrogen. A signal photon is generated by a trigger photon and coherence among…
Coherent two-photon emission from hydrogen molecules excited by counter-propagating laser pulses
Takahiro Hiraki, Hideaki Hara, Yuki Miyamoto +7
We observed two-photon emission signals from the first vibrationally excited state of parahydrogen gas excited coherently by counter-propagating laser pulses. A single narrow-linew…