Dr. N. Cunningham

IRAM, France

Infall and Outflow Motions towards a Sample of Massive Star Forming Regions

Abstract:

Infall and outflow motions are an imperative part of the star formation process. However, we currently lack a clear understanding of how they change with evolutionary stage and how infall and outflow motions influence the formation process. I will present results of a distance limited outflow and infall survey undertaken with the JCMT towards a sample of 31 MYSOs and ultra-compact HII (UCHII) regions drawn from the RMS survey (Cunningham et al. 2018). Where, the presence of young, active outflows is identified from the SiO (8-7) emission and previous CO (3-2) data (Maud et al. 2015b) are used to determine outflow properties. The infall motions and bulk properties of each region are determined from the HCO+/H13CO+ (4-3) emission. Active outflows are detected towards approximately 50% of our sample compared with <10% of the sources displaying infall signatures. I will discuss the differences found towards massive star forming hosting active outflows compared with those hosting potentially fossil, momentum outflows. In addition, I will show a comparison of the JCMT results, which trace larger spatial scales, with previous high spatial resolution SMA observations for a sub-sample of these regions (Cunningham et al. 2016). Finally, I will present some recent Green Bank Telescope observations of HCO+/H13CO+ (1-0) taken with the new instrument, Argus (~9" resolution), towards a sub-set of these regions. These new observations allow us to explore and trace kinematics on cloud scales down to core type scales at a resolution of <0.1pc, providing a valuable comparison between the infall kinematics traced by HCO+ (4-3) and HCO+ (1-0) in these regions.

Location: 31 Fitzwilliam Place, Dublin 2

Upcoming seminars:
https://www.dias.ie/2018/03/07/astronomy-and-astrophysics-seminar-schedule-2018/