Abstract. We present the final data release of observations of λ21-cm emission from Galactic neutral hydrogen over the entire sky, merging the Leiden/Dwingeloo Survey (LDS: Hartmann & Burton 1997, Atlas of Galactic Neutral Hydrogen) of the sky north of δ = −30• with the Instituto Argentino de Radioastronomía Survey (IAR: Arnal et al. 2000, A&AS, 142, 35; and Bajaja et al. 2005, A&A, 440, 767) of the sky south of δ = −25• . The angular resolution of the combined material is HPBW ∼ 0.• 6. The LSR velocity coverage spans the interval −450 km s −1 to +400 km s −1 , at a resolution of 1.3 km s −1 . The data were corrected for stray radiation at the Institute for Radioastronomy of the University of Bonn, refining the original correction applied to the LDS. The rms brightness-temperature noise of the merged database is 0.07−0.09 K. Residual errors in the profile wings due to defects in the correction for stray radiation are for most of the data below a level of 20−40 mK. It would be necessary to construct a telescope with a main beam efficiency of η MB > ∼ 99% to achieve the same accuracy. The merged and refined material entering the LAB Survey of Galactic H  is intended to be a general resource useful to a wide range of studies of the physical and structural characteristices of the Galactic interstellar environment. The LAB Survey is the most sensitive Milky Way H  survey to date, with the most extensive coverage both spatially and kinematically.

Abstract. We present the final data release of the high sensitivity λ 21-cm neutral hydrogen survey of the sky south of δ ≤ −25• . A total of 50 980 positions lying on a galactic coordinate grid with points spaced by (∆l, ∆b) = (0.• 5/cos b, 0.• 5) were observed with the 30-m dish of the Instituto Argentino de Radioastronomía (IAR). The angular resolution of the survey is HPBW = 0.• 5 and the velocity coverage spans the interval −450 km s −1 to +400 km s −1 (LSR). The velocity resolution is 1.27 km s −1 and the final rms noise of the entire database is 0.07 K. The data are corrected for stray radiation and converted to brightness temperatures.

Abstract. This paper reports on a high sensitivity λ 21-cm neutral hydrogen survey of the sky south of δ ≤ −25• . A total of 50980 positions lying on a galactic coordinate grid with points spaced by ( l, b) = (0.• 5/cos b, 0.• 5), were observed with the 30 m dish of the Instituto Argentino de Radioastronomía (IAR). The angular resolution of the survey is HPBW = 30 , and the velocity coverage spans the interval −450 km s −1 to +400 km s −1 (LSR). The velocity resolution is 1.27 km s −1 and the final rms noise of the entire database is ∼ 0.07 K. The brightness temperature scale is accurate to 5%.

Abstract.A new high-sensitivity HI survey of the southern sky was made south of Declination −25• , at the Instituto Argentino de Radioastronomía (IAR), on a halfdegree grid in galactic coordinates. A total of 50980 positions were observed. One of the goals of this survey was to search for high velocity clouds (HVCs). The HI profiles have been smoothed to a velocity resolution of 8 km s −1 . The resulting rms noise falls in the range 0.015 to 0.020 K. We have detected 6848 high velocity (HV) components.

Aims. We want to make a large-scale study of the morphology, kinematics, and origin of the H I, which surrounds the Sco-Cen association. Methods. We combine our high-sensitivity southern H I survey with the Leiden/Dwingeloo Survey, considering l = 240 • −400 • , b = −60 • to +60 • , and radial velocities of V = −41.8 to +40.8 km s −1 . We point out the main H I branches surrounding the association and derive their kinematics. Kinematical H I-maps were compared with spatial maps of interstellar (IS) Na I from the literature. Upper limits for distances d were derived from optical IS absorption components from the literature. Models of expanding spherical H I shells were fitted around each stellar subgroup. Results. The expanding ring of H I associated with the Gould Belt (GB) is very prominent. At each l, its radial velocity shifts ∼−7 km s −1 within an interval Δb ∼ 10 • −25 • . On the sky, the shifts occur within a narrow stripe extending between l, b ∼ 250 • , −18 • and 400 • , +50 • . The ranges of distances and radial thicknesses of most H I branches are nearly 70−160 pc and 40−90 pc, respectively. The shell-models fit the main branches. Interactions between the shells built a large expanding bubble with a transverse diameter of nearly 250 pc around the association. The near face is approaching with a mean velocityV ∼ −6.6 km s −1 at d ≤ 76 pc from the Sun, covering about 102 • × 65 • (l, b), forming an "H I-wall". There are streamers atV ∼ −15 to −35 km s −1 , as well as gas presumably overshot into Galactic Quadrant II. The receding gas is more tenuous. Conclusions. The association is traversing the ring since a time comparable to its age producing a significant disturbance on the expanding GB-ring of gas. The latter was almost totally shocked by the association, northerly of the stripe of velocity shifts. Southerly there are large amounts of preshocked gas, as well as smaller more localized shocked regions. Hot gas within the bubble produces most of the 1/4 keV radiation detected toward it by ROSAT. The total mass of the GB gas embedding the Sco-Cen association is estimated at M t ∼ 368 000 M ± 60%, including ∼34 000 M of associated H 2 and 30% of He. About 39% of the embedding gas was shocked by the association. At | b |≥ 35 • , a comparison of the observations with test points moving on ballistic orbits is consistent with the formation of the Sco-Cen association within the gas ring of the GB and the presumable explosive origin of the latter. The rotation of the ring is assumed.