TIMASSS. I. IRAS 16293-2422 spectra

All the lines detected with more than 3-sigma confidence-interval certainty and free from obvious blending effects were fitted with Gaussians to estimate their basic kinematic properties. More than 4000 lines were detected (with sigma>=3) and identified, yielding a line density of approximatively 20 lines per GHz, comparable to previous surveys in massive hot cores. The vast majority (about two-thirds) of the lines are weak and produced by complex organic molecules.

The analysis of the profiles of more than 1000 lines belonging to 70 species firmly establishes the presence of two distinct velocity components associated with he two objects, A and B, forming the IRAS 16293-2422 binary system. In the source A, the line widths of several species increase with the upper level energy of the transition, a behavior compatible with gas infalling towards a ~1M_{sun}_ object. The source B, which does not show this effect, might have a much lower central mass of ~0.1M_{sun}_.

The difference in the rest velocities of both objects is consistent with the hypothesis that the source B rotates around he source A. Conclusions. This spectral survey, although obtained with single-dish telescopes at a low spatial resolution, allows us to separate the emission from two different components, thanks to the large number of lines detected.