EPoS Contribution
EPoS Contribution
[Fe II] 1.64 um imaging observations of Jets and Outflows from Young Stellar Objects in the Carina Nebula

Jong-Ho Shinn
KASI, Daejeon, SouthKorea
We present [Fe II] 1.64 um imaging observations for jets and outflows from young stellar objects over the northern part (~24′x45′) of the Carina Nebula, a typical evolved massive star forming region. The observations were performed with IRIS2 of Anglo-Autralian Telescope and the seeing was ~1.5′′. Several jets and outflows features are detected at seven different regions, and one new Herbig-Haro Object, previously missed, is identified using our [Fe II] images. The [Fe II] features have knotty and elongated shapes, and distribute around the triangular area formed by the star clusters Tr 14, Tr 15, and Tr 16, which contain many massive stars. The [Fe II] feature shows a highest detection rate (3.2 %) for the earliest stage YSOs, and the rate decreases as the stage evolves. The low detection rate (1.5 %) of [Fe II] features from the numerous YSOs seem to be related with the severe radiation environment of the Carina Nebula. The outflow rate shows reasonable relations with the physical parameters of the corresponding YSOs—derived from the SED fitting—such as the accretion luminosity, the stellar mass, the stellar age, the disk accretion rate, etc. The masses of YSOs are low and intermediate, and their final masses are not likely to exceed ~8 solar mass. The stellar age shows two distinctive distributions for the stage 0/I and II YSOs (~10^4 yr and ~10^6 yr), which suggests these YSOs were collapsed at two different epochs. The ratio of the outflow rate over the disk accretion rate are higher than the previously reported value by a factor of ~10^3−10^4. This may be from the overestimation of the outflow rate, for whose estimation a few assumptions are made, and possibly the imprecision of the disk accretion rate analytically calculated in the SED model.
T.-S. Pyo, NAOJ, Japan
J.-J. Lee, KASI, South Korea
H.-G. Lee, Univ. Tokyo, Japan
B.-C. Koo, Seoul Nat'l Univ., South Korea
H. Sung, Sejong Univ., South Korea
D.-S. Moon, Univ. Toronto, Canada
J. Kyeong, KASI, South Korea
B.-G. Park, KASI, South Korea