Equation of state and sound velocity for cesium at temperatures up to 2200K and pressures to 60 MPa

Results are presented of the measurement of the equation of state and sound velocity for cesium. The equation of state is measured at temperatures up to 2200K and pressures up to 60 MPa in the liquid and gaseous phases; the measurements include the coexistence curve up to the critical point and in the supercritical region. The experimental error of the density data lies between 0.2 and 1.0%. The critical parameters for cesium are found to be 1938K, 9.4 MPa and 0.39 gxcm-3. The sound velocity is measured in the liquid phase at temperatures up to 2000K and pressures up to 60 MPa with an accuracy to 0.5-0.6%. The data obtained are used to set up tables of the thermal and caloric properties of liquid cesium. The problems pertaining to the shape and diameter of the coexistence curve and of the specific heat of cesium at constant volume are discussed. It is shown that the critical region of cesium is smaller by two orders of magnitude than that of dielectrics