Periodic Reporting for period 1 - SMART (Star formation history of MAssive pRoTostars)
Berichtszeitraum: 2021-04-01 bis 2023-03-31
Determining how massive stars form, i.e. those stars with more than 8 times the mass of our Sun, is important for many reasons. They are key for regulating galaxies, the interstellar medium, and the star formation process itself. There is some evidence our own Solar System was influenced by massive stars in its early history. However, massive stars are rare compared to their lower-mass 1 brethren and thus tend to be found in formation sites that are relatively far from the Sun, typically >1 kpc away. During the protostellar phase, these stars also tend to be highly obscured by the gas and dust of their parental molecular cloud. For these reasons, despite their importance, the formation mechanism of massive stars is still poorly understood.
The overall objective of the SMART project is to shed further light on the formation of massive protostars. To do this we have an observational approach by peering into the heart of massive star-forming regions using the most powerful telescopes on Earth and space, which include the Hubble Space Telescope (HST), the Very Large Telescope (VLT), and the Large Binocular Telescope (LBT). By analysing images and spectra, we aim to fully characterize the central forming protostar, its jets and outflows, as well as its surrounding environment. This work will greatly contribute to our understanding of this important, yet poorly understood, aspect of astrophysics.
Using data from the SMART project, I have trained an undergraduate student. The student and I analysed the high-mass star-forming region IRAS18264-1152 in order to tackle the WP1 ‘Physical properties of massive protostellar jets in the NIR’. We found that massive protostars can form in a relatively ordered manner. This is important to understand to which extent the formation of stars is uniform across the mass spectrum. This research was published in the first quartile journal Astronomy and Astrophysics and was presented at several international meetings in the form of talks and posters.
As part of the SMART research plan, in particular addressing the WP2 ‘NIR characterisation of the protocluster environment’, I have analysed 40 star-forming regions and created the open-source Python package sedcreator. This analysis has provided valuable insights into the star formation process and has been published in The Astrophysical Journal which is ranked in the first quartile of astronomy journals. In particular, we found that to form protostars with more than 10 times the mass of our Sun, one does not need mass surface density above 1 g/cm2, which challenges current theories. We note though that these are indirect measurements and further investigation is needed to draw stronger conclusions.