We apply ultrafast single shot interferometry to determine the pressure and density of argon shocked from up to 7.8 GPa static initial pressure in a diamond anvil cell. This method enables the observation of thermodynamic states distinct from those observed in either single shock or isothermal compression experiments, and the observation of ultrafast dynamics in shocked materials. We also present a straightforward method for interpreting ultrafast shock wave data which determines the index of refraction at the shock front, and the particle and shock velocities for shock waves in transparent materials. Based on these methods, we observe shocked thermodynamic states between the room temperature isotherm of argon and the shock adiabat of cryogenic argon at final shock pressures up to 28 GPa.

The authors present a Dalitz-plot analysis of charmless B{sup {+-}} decays to the final state {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}} using a sample of (465 {+-} 5) x 10{sup 6} B{bar B} pairs collected by the BABAR experiment at {radical}s = 10.58 GeV. They measure the branching fractions {Beta}(B{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}}) = (15.2 {+-} 0.6 {+-} 1.2 {+-} 0.4) x 10{sup -6}, {Beta}(B{sup {+-}} {yields} {rho}{sup 0}(770){pi}{sup {+-}}) = (8.1 {+-} 0.7 {+-} 1.2{sub -1.1}{sup +0.4}) x 10{sup -6}, {Beta}(B{sup {+-}} {yields} f{sub 2}(1270){pi}{sup {+-}}) = (1.57 {+-} 0.42 {+-} 0.16{sub -0.19}{sup +0.53}) x 10{sup -6}, and {Beta}(B{sup {+-}} {yields} {pi}{sup {+-}}{pi}{sup {+-}}{pi}{sup {-+}} nonresonant) = (5.3 {+-} 0.7 {+-} 0.6{sub -0.5}{sup +1.1}) x 10{sup -6}, where the uncertainties are statistical, systematic, and model-dependent, respectively. Measurements of branching fractions for the modes B{sup {+-}} {yields} {rho}{sup 0}(1450){pi}{sup {+-}} and B{sup {+-}} {yields} f{sub 0}(1370){pi}{sup {+-}} are also presented. They observe no significant direct CP asymmetries for the above modes, and there is no evidence for the decays B{sup {+-}} {yields} f{sub 0}(980){pi}{sup {+-}}, B{sup {+-}} {yields} {chi}{sub c0}{pi}{sup {+-}}, or B{sup {+-}} {yields} {chi}{sub c2}{pi}{sup {+-}}.