Program: GN-2006B-C-9

// Three NIFS proposals combined into one // /// G/2006B/012 /// High-Mass Protostar Enivironments - W3 IRS 5 W3 IRS 5 is a high-mass protostar system in the W3 star forming region at a distance of ~ 1.8 kpc (Imai et al. 2000, ApJ, 538, 751). It has long been known to be a binary protostar with both components powering hyper-compact H II regions. Recent NICMOS images reveal nebulous emission between the two high-mass protostars. This emission could arise through interaction between the two protostar outflows, through photo-ionization of adjacent massive accretion disks, or through mechanical interaction between the two accretion disks. We propose to obtain sub-arcsecond spatially-resolved near-infrared spectra with NIFS+ALTAIR/LGS of the two protostars and this intervening emission to establish its nature. /// G/2006B/015 /// The Driving Mechanism of Young Stellar Object Jets A small number of T Tauri stars and other Young Stellar Objects (YSOs) possess well-collimated outflows that are revealed by subarcsecond-scale "microjets". These microjets are seen in emission lines of shock-excited forbidden transitions and molecular hydrogen. The structure and dynamics of the jet can be used to infer information about the accretion envelope of the star and the mechanisms controlling mass inflow and jet collimation. We propose to use NIFS+ALTAIR/NGS to study these structures in the classic T Tauri star, CW Tau, and the edge-on disk system, Haro 6-5B. /// G/2006B/013 /// What Powers Activity in the Cores of Seyfert Galaxies? The near-infrared region contains several spectral features that by virtue of their low excitation can be excited by either star formation or AGN activity. We will use high resolution 2D spatial information, in addition to excitation and velocity data, to explore the origins of the [Fe II] and H_2 emission in Seyfert galaxies in which the radio emission is spatially resolved on arcsecond scales. These features can arise in shocks associated with the radio jet, or by X-ray photoionization from the AGN. Radial velocity dispersion profiles of the circumnuclear stellar population measured from 2.3 micron CO absorption bands will be used to constrain the central black hole mass.