Three's A Crowd: The Jets, Envelopes, And Environment Of PDS 144

PDS 144 has been identified as an intermediate-mass analog of T Tauri wide binaries such as HK Tau, where at least one member of the binary is viewed at high inclination. The presence of bipolar jets is common in T Tauri binaries; we have obtained medium-band (FWHM=110-200 A) and narrow-band (FWHM=120 km/s) direct imagery of the of the PDS 144 system to determine whether intermediate-mass binaries also drive jets. Bipolar outflows are detected for both stars. For PDS 144N, the jet is directed along PA=137 degrees and is orthogonal to the previously imaged disk. For PDS 144S, the jet is along PA=302 degrees. After PSF subtraction, the image of PDS 144S is asymmetric and extended, which is inconsistent with expectations for what had been thought to be a star viewed at low inclination. We confirm the presence of extended, reflection nebulosity detected at 0.8 and 0.55 microns in HST/ACS imagery after PSF subtraction. The nebulosity is consistent with a bipolar outflow cavity which is bisected by the jet. The faint star located between PDS 144N and S also drives a bipolar jet. As a multiple star system with two imaged disk/envelopes and 3 bipolar jets, the PDS 144 system closely resembles T Tauri binary/multiple systems at ages less than 2 Myr, and offers similar potential in studies of grain growth and settling, as well as for accretion and mass loss studies.

This study was funded by HST-GO-11155 and NASA RTOP 399131.02.02.02.32 to Goddard Space Flight Center. The Apache Point observations were made under a grant of Director's Discretionary Time.