Speaker
Diederik Kruijssen
(MPA Garching)
Description
Galactic star formation (SF) relations are known to develop substantial scatter or even change form when considered below a certain spatial scale. I will quantify how this behaviour should be expected due to the incomplete statistical sampling of independent star-forming regions. Other included limiting factors are the incomplete sampling of SF tracers from the stellar initial mass function and the spatial drift between gas and stars. I will present a simple uncertainty principle for SF, which can be used to predict and interpret the failure of galactic SF relations on small spatial scales. I show how the scatter and bias of SF relations are sensitive to the physical size and time-scales involved in the SF process. As a result, this new formalism provides a powerful tool to constrain largely unknown quantities such as the duration of SF. Using multiple gas tracers, it also allows one to map the density evolution of the ISM towards SF as a function of absolute time. I will present the first results of applying the uncertainty principle to observations, as well as some preliminary results from numerical simulations.
Author
Diederik Kruijssen
(MPA Garching)