A2048 - First Results

The first pass of the AGESGAL1156 area was completed in December, 2005, reaching twice the integration time of ALFALFA. A quick inspection of the cube by eye reveals 10 sources, including NGC 1156 and a 4 galaxies between 10,000 and 11,000 km/s. The 10 sources include two 2MASS sources with no previously known redshifts and one previously uncatalogued source.

Moment 0 map of the previously uncatalogued source.

Spectrum of the previously uncatalogued source.

Digitized Sky Survey image of the previously uncatalogued source, with Moment 0 contours overlaid at 5, 10, 15 and 20 sigma. There is no obvious optical counterpart, but this appears to be a dusty region with about 1.5 mags of absorption in B.

The source is at a redshift of 3280 km/s, giving a distance of 47 Mpc for H₀ of 70. The flux is 1.1 Jy km/s, giving an HI mass of 5.8 10⁸ solar masses. It has a 50% velocity width of 46 km/s and a 20% velocity width of 63 km/s.

The noise in the first-pass coverage of the AGESGAL1156_p1a, to an integration time of about 50s. This shows a noise of around 2 mJy/channel/beam, which is consistent with the estimated final noise of 0.5 - 1 mJy/channel/beam prior to smoothing.