%0 Journal Article %T Massive and low-mass protostars in massive ¡°starless¡± cores %A Carsten K£¿nig %A Jens Kauffmann %A Ke Wang %A Patricio Sanhueza %A Qizhou Zhang %A Silvia Leurini %A T. K. Sridharan %A Thushara Pillai %J - %D 2019 %R 10.1051/0004-6361/201732570 %X The infrared dark clouds (IRDCs) G11.11£¿0.12 and G28.34+0.06 are two of the best-studied IRDCs in our Galaxy. These two clouds host clumps at different stages of evolution, including a massive dense clump in both clouds that is dark even at 70 and 100 ¦̀m. Such seemingly quiescent massive dense clumps have been speculated to harbor cores that are precursors of high-mass stars and clusters. We observed these two ¡°prestellar¡± regions at 1 mm with the Submillimeter Array (SMA) with the aim of characterizing the nature of such cores. We show that the clumps fragment into several low- to high-mass cores within the filamentary structure of the enveloping cloud. However, while the overall physical properties of the clump may indicate a starless phase, we find that both regions host multiple outflows. The most massive core though 70 ¦̀m dark in both clumps is clearly associated with compact outflows. Such low-luminosity, massive cores are potentially the earliest stage in the evolution of a massive protostar. We also identify several outflow features distributed in the large environment around the most massive core. We infer that these outflows are being powered by young, low-mass protostars whose core mass is below our detection limit. These findings suggest that low-mass protostars have already formed or are coevally formed at the earliest phase of high-mass star formation %U https://www.aanda.org/articles/aa/full_html/2019/02/aa32570-17/aa32570-17.html