Two scenarios have been proposed to explain the evolution of star-forming cores: the gravitational fragmentation of larger structures and the coalescence of smaller entities that are formed from some instabilities. Here, we turn our attention to the latter idea in order to investigate the evolution of observed low-mass condensations (LMCs) in the cores of molecular clouds. For this purpose, we implement the evolution of the observed LMCs of the Taurus molecular cloud 1 (TMC-1). The core is modelled as a contracting cylinder with randomly spawned condensations in the middle region around its axis. For advancing bodies in their trajectories, we represent the acceleration of a particular LMC in terms of a fourth-order polynomial using the predictor–corrector scheme. Whenever two LMCs collide, they are assumed to be merged in one large condensation containing all the masses of the two progenitors. Implementations of many computer experiments with a wide variety of free parameters show that the LMCs merge to form star-forming regions in the core. The results show that the total mechanical energy of the core increases in time, and its rate of increase decreases by facilitating the merger. Finally, the mass spectrum index and the goodness-of-fit are determined with a 50 per cent error in the number of mass points. The results show that the goodness-of-fit will be refined at the end of simulations, and the mass spectrum index inclines to the observed values for moderate-mass objects. The simulations show that the TMC-1 turns about 40 per cent of its mass into a cluster of dynamically unstable protostellar cores. In general, we suggest that the future of LMCs in a core of molecular cloud is merger to convert about half of its initial masses into a cluster of gravitationally unstable protostellar cores.
Keywords: methods: numerical; stars: formation; ISM: clouds; ISM: evolution
Journal Article. 4353 words. Illustrated.
Subjects: Astronomy and Astrophysics
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