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arXiv · 2511.17769

Outflow Interaction in Cep-E: Numerical Simulation and Observational Manifestation

A. Rodríguez-González·P. R. Rivera-Ortiz·Z. Meliani·E. Alquicira-Peláez·A. Durán·Luis A. Zapata
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Abstract

There is clear observational evidence that the main Class 0/I stages of the star formation process are associated with powerful collimated outflows (jets), which sometimes propagate up to distances as large as $10^{4-5}$ au scales in molecular clouds. Additionally, intermediate high-mass and low-mass protostars have often been observed to form in crowded clusters, where the typical separation distance between any two cluster members is of the same order or smaller than the scale of the outflow length. Therefore, there must be an interaction between the molecular outflows of different protostars within the protostellar association. A good example of this is the case of Cepheus E-mm, which is a protostellar outflow extending over a few dozen au. At its core is a binary system consisting of two protostars, Cep E-A and Cep E-B, separated by about 1000 au. Both protostars eject molecular jets at velocities of ~100 km/s. The interaction between these molecular outflows provides an opportunity to study the effects of jet collisions in a clustered star-forming environment, as they may leave detectable imprints on the morphology of the main envelope of the system. Our work aims to study the effects of the collision of molecular jets associated with the components of the binary system Cep-A and Cep-E, analyzing the disruption or reduction of molecular emission in the main envelope of the system, which the molecular outflow { launched} by Cep-A presumably pushes. If we characterize the collision in this system, we can provide insights into the expected morphology and molecular emissions in collisions of molecular outflows { associated to star forming process.

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A. Rodríguez-González, P. R. Rivera-Ortiz, Z. Meliani, E. Alquicira-Peláez, A. Durán, Luis A. Zapata. 2025-11-21. Outflow Interaction in Cep-E: Numerical Simulation and Observational Manifestation. https://arxiv.org/abs/2511.17769

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