We describe an optical diagnostic setup which permits simultaneous spatially and temporally resolved measurements of temperature and density from cold, dense laserhyphen;produced plasmas. Such information is necessary to investigate the physics of strongly coupled plasmas. The plasma is created in a slab geometry such that the transverse slab dimension is approximately one optical depth of the probing radiation in thickness. To perform the measurements the 2nd harmonic (lgr;=0.527 mgr;m) of a modehyphen;locked Nd:glass laser (tgr;pulse=300ndash;500 ps) is split into two orthogonally polarized beams. One of the beams measures plasma electron density using polarization wave front interferometry. The other beam uses a set of fast (tgr;=350 ps) photodiodes to measure singlehyphen;frequency optical absorption. Plasma electron temperature is determined from timehyphen;resolved absolute emission measurements combined with the optical absorption measurements via Kirchoffrsquo;s law. This technique avoids the difficulties involved in spectroscopic temperature measurements, where the spectral intensities and line profiles are affected by the physics of the cold, dense plasma. A set of timing fiducials allows the entire set of diagnostics to be synchronized in time, while an accurate, selfhyphen;referenced alignment system assures that all diagnostics sample the same region of plasma volume.
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