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We present new high resolution (R>50,000) absorption measurements of the NaIdoublet (5889 - 5895A) along 482 nearby sight-lines, in addition to 807 newmeasurements of the CaII K (3933A) absorption line. We have combined these newdata with previously reported measurements to produce a catalog of absorptionstowards a total of 1857 early-type stars located within 800pc of the Sun. Usingthese data we have determined the approximate 3-dimensional spatialdistribution of neutral and partly ionized interstellar gasdensity within adistance-cube of 300pc from the Sun. All newly recorded spectra were analyzedby means of a multi-component line profile-fitting program, in most cases usingsimultaneous fits to the line doublets. Normalized absorption profiles werefitted by varying the velocity, doppler width and column density for allintervening interstellar clouds. The resulting total column densities were thenused in conjunction with the Hipparcos distances of the target stars toconstruct inversion maps of the 3-D spatial density distribution of the NaI andCaII bearing gas. A plot of the equivalent width of NaI versus distance revealsa wall of neutral gas at ~80pc that can be associated with the boundary wall tothe central rarefied Local Cavity region. In contrast, a similar plot for theequivalent width of CaII shows no sharply increasing absorption at 80pc, butinstead we observe a slowly increasing value of CaII equivalent width withincreasing sight-line distance sampled.

New 3-D gas density maps of NaI and CaII interstellar absorption within 300pc