| Description |
Stars form from contracting molecular cloud cores, but this process reliesheavily on the ability of the core to cool and to overcome the magneticbarrier; this, in turn, depends on the chemical composition and couldtherefore lead to drastically different outcomes at low metallicity. However,most of what we know about star formation is derived from studies ofsolar-metallicity YSOs in the Milky Way. To investigate the role ofmetallicity on the star-formation process we propose to observe a sample ofearly-stage massive young stellar objects in the metal-poor Small and LargeMagellanic Clouds. These were selected from among sources with spectroscopicevidence of ice and/or maser emission, and comprise a range in luminosity. Wepropose to use PACS and SPIRE FTS to measure the strengths of key atomic andmolecular lines, in order to measure the temperature, density, ionizationstate and abundances of the main cooling species in these objects. Bycomparing the SMC and LMC samples, and Galactic samples of YSOs, we willassess the effect of the reduced metallicity on the formation process ofmassive stars. |
