A high sensitivity HI survey of the sky at δ ≤-25°

This paper reports on a high sensitivity lambda 21-cm neutral hydrogen survey of the sky south of delta less than or equal to -25 degrees. A total of 50980 positions lying on a galactic coordinate grid with points spaced by (Delta l, Delta b) = (0 degrees.5/cos b, 0 degrees.5), were observed with the 30 m dish of the Instituto Argentino de Radioastronomia (IAR). The angular resolution of the survey is HPBW = 30', and the velocity coverage spans the interval -450 kms(-1) to +400 kms(-1) (LSR). The velocity resolution is 1.27 kms(-1) and the final rms noise of the entire database is similar to 0.07 K. The brightness temperature scale is accurate to 5%.