Figure: The proto-planetary disk around the T Tauri star GM Aur, observed with the Plateau de Bure interferometer on Nov 9, 1995 (1.5 hours of integration).
Figure 4 is a result of observations at 230 GHz obtained on Nov 9, 1995. The array was in the most compact configuration (baselines from 24 to 64 meters), which already gives about resolution at the CO J=2-1 frequency. The figure shows images of the integrated intensity of the CO J=2-1 line, of the velocity field and of the line width of a proto-planetary disk around the T Tauri star GM Aur. The integrated spectrum is also shown. The data were obtained in snapshot mode (4 sources were observed during the same transit), so that the total integration time on source is less than 1.5 hours.
Keplerian rotation had been previously detected by aperture synthesis observations of CO J=2-1 performed at OVRO (Koerner, Sargent & Beckwith 1993, Icarus 106, 2), with an angular resolution of by . Despite the very short integration time, the Plateau de Bure data significantly improve the angular resolution and unambiguously confirm the Keplerian rotation.