Ejection processes in the young open cluster NGC 2264. A study of the [OI]{\lambda}6300 emission line.

We search for correlations between the [OI]6300 line, a well-known tracer of jets and winds in young stars, and stellar/disk/accretion properties in the young cluster NGC 2264, aiming to characterize the outflow phenomena that occur within the circumstellar environment. We analyzed FLAMES spectra of 184 stars, detecting the [OI]6300 line in 108 CTTSs and 2 Herbig AeBe stars. We identified the main features of this line: a high-velocity component (HVC), and a broad and narrow low-velocity components (BLVC and NLVC). We calculated their luminosities and kinematic properties, then compared with stellar/accretion parameters. The luminosity of the [OI]6300 line correlates positively with the stellar and accretion luminosity. The HVC is only detected among systems with optically thick inner disks; the BLVC is found in thick disk systems and few systems with anemic disks; and the NLVC is common among systems with all types of disks. Our BLVCs present blueshifts of up to 50km/s and widths compatible with an origin 0.05au-3au from the star. The NLVCs have centroid velocities and widths consistent with what may be expected for photoevaporative disk winds originating between 1 and 15au. The HVC is found most often among sources with irregular, aperiodic photometric variability, usually associated with accretion in an unstable regime. The mechanical luminosity transported by jets correlates positively with the accretion luminosity, but no stellar properties appear to significantly influence any property of these jets. We find jet velocities on average similar to those found in Taurus. We confirm earlier findings in Taurus which favor an inner MHD disk wind as the origin of the BLVC, while the NLVC might trace photoevaporative disk winds. The [OI]6300 line profile shows signs of evolving as the disk disperses, with the HVC and BLVC disappearing as the inner disk becomes optically thin.