The unexpectedly large proportion of high-mass star-forming cores in a Galactic mini-starburst. (June 2018)

• Record Type: Journal Article
• Authors: Motte, F.; Nony, T.; Louvet, F.; Marsh, K.; Bontemps, S.; Whitworth, A.; Men'shchikov, A.; Nguyễn Lương, Q.; Csengeri, T.; Maury, A.; Gusdorf, A.; Chapillon, E.; Könyves, V.; Schilke, P.; Duarte-Cabral, A.; Didelon, P.; Gaudel, M.
• Is Part Of: Nature astronomy. Volume 2:Number 6(2018)
• Page Start: 478
• Page End: 482
• Publication Date: 2018-06
• Subjects: Astronomy -- Periodicals; 520.5
• DOI: 10.1038/s41550-018-0452-x
• Languages: English
• ISSNs: 2397-3366

Abstract

Abstract Understanding the processes that determine the stellar initial mass function (IMF) is a critical unsolved problem, with profound implications for many areas of astrophysics1 . In molecular clouds, stars are formed in cores—gas condensations sufficiently dense that gravitational collapse converts a large fraction of their mass into a star or small clutch of stars. In nearby star-formation regions, the core mass function (CMF) is strikingly similar to the IMF, suggesting that the shape of the IMF may simply be inherited from the CMF2–5 . Here, we present 1.3 mm observations, obtained with the Atacama Large Millimeter/submillimeter Array telescope, of the active star-formation region W43-MM1, which may be more representative of the Galactic-arm regions where most stars form6, 7 . The unprecedented resolution of these observations reveals a statistically robust CMF at high masses, with a slope that is markedly shallower than the IMF. This seriously challenges our understanding of the origin of the IMF. In Galactic star-forming region W43-MM1 the core mass function (CMF), describing the mass distribution of the birthplaces of stars, is very different from the initial mass function (IMF), the mass distribution of newborn stars. Previously, the IMF was thought to reflect the CMF.