Watching how stars are being born in Orion
Thesis Supervisor: Thomas Stanke
The Giant molecular clouds in the Orion constellation are the most nearby examples of clouds forming stars over the entire mass range up to O-type stars. The population of young stellar objects is very well known, thanks to extensive infrared surveys, such as the Herschel Orion Protostar survey (HOPS). Wide field (sub)millimetre continuum surveys at 1.3mm (IRAM 30m), 850mum (APEX Laboca), and 350mum (APEX Saboca) reveal the distribution of the dense, cold gas from which the current and next generation of stars is and will be forming (see https://www.eso.org/public/news/eso1321/). The more tenous molecular gas is traced by wide field CO maps taken with the JCMT and APEX (SuperCam: APEX Large CO Heterodyne Orion Legacy Survey ALCOHOLS) and indicates the properties of the environment (temperatures, turbulence) and reveals the presence of protostellar outflows.
The existing data will be the foundation of the PhD project, likely to be complemented by additional observational studies, mostly at (sub)millimeter wavelengths (e.g., APEX, ALMA), and/or ALMA archival data, will be compared to model predictions of cloud core formation, and will allow to investigate a number of questions, e.g.:
How do protostellar cores condense out of the surrounding dense gas, and are filaments really needed for that to happen?
What is the radial density structure of protostellar cores and envelopes, and how does it evolve in the course of the stellar birth?
Can we find "first cores" (a short lived phase right after the onset of collapse, postulated to exist from star formation calculations and simulations since the 1960's, but not yet conclusively detected due to their faintness and rarity)?
How do protostellar outflows evolve in the earliest phase of star formation?