title: Laser-shock compression of magnesium oxide in the warm-dense-matter regime.
abstract: Magnesium oxide has been experimentally and computationally investigated in the warm-dense solid and liquid ranges from 200 GPa to 1 TPa along the principal Hugoniot. The linear approximation between shock velocity and particle velocity is validated up to a shock velocity of 15 km/s from the experimental data, this suggesting that the MgO B1 structure is stable up to the corresponding shock pressure of ∼350 GPa. Moreover, our Hugoniot data, combined with ab initio simulations, show two crossovers between MgO Hugoniot and the extrapolation of the linear approximation line, occurring at a shock pressures of approximately 350 and 650 GPa, with shock temperatures of 8000 and 14,000 K, respectively. These crossover regions are consistent with the solid-solid (B1-B2) and the solid-liquid (B2-melt) phase boundaries predicted by the ab initio calculations.
authors.affiliation: Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Miyanishi
authors.affiliation: Japan Synchrotron Radiation Research Institute, Sayo, Hyogo 679-5198, Japan.|Geodynamics Research Center, Ehime University, Matsuyama, Ehime 790-8577, Japan.|Earth-Life Science Institute Ehime Satellite, Tokyo Institute of Technology, Meguro, Tokyo 152-8550, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tange
authors.affiliation: Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.|Photon Pioneers Center, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Ozaki
authors.affiliation: Geodynamics Research Center, Ehime University, Matsuyama, Ehime 790-8577, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kimura
authors.affiliation: Institute of Laser Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sano
authors.affiliation: Institute of Laser Engineering, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Sakawa
authors.affiliation: Geodynamics Research Center, Ehime University, Matsuyama, Ehime 790-8577, Japan.|Earth-Life Science Institute Ehime Satellite, Tokyo Institute of Technology, Meguro, Tokyo 152-8550, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Tsuchiya
authors.affiliation: Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871, Japan.|Photon Pioneers Center, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Kodama