VLBI multi-epoch water maser observations toward massive protostars

Abstract

VLBI multi-epoch water maser observations are a powerful tool to study the gas very close to the central engine responsible for the phenomena associated with the early evolution of massive protostars. In this paper we present a summary of the main observational results obtained toward the massive star-forming regions of Cepheus A and W75N. These observations revealed unexpected phenomena in the earliest stages of evolution of massive objects (e.g., non-collimated "short-lived" pulsed ejections in different massive protostars), and provided new insights in the study of the dynamic scenario of the formation of high-mass stars (e.g., simul- taneous presence of a jet and wide-angle outflow in the massive object Cep A HW2, similar to what is observed in low-mass protostars). In addition, with these observations it has been possible to identify new, previously unseen centers of high-mass star formation through outflow activity.

Submitted to Proceedings of IAU Symposium No. 287, Cosmic Masers- from OH to Ho

References in corpus (6)

• A Magnetized Jet from a Massive Protostar
• A Photoevaporating Rotating Disk in the Cepheus A HW2 Star Cluster
• Clustered star formation and outflows in AFGL 2591
• The Circumstellar Structure and Excitation Effects around the Massive Protostar Cepheus A HW 2
• A rotating molecular disk toward IRAS 18162-2048, the exciting source of HH 80-81
• Jets and Wide Angle Outflows in Cepheus E: New Evidence from Spitzer

Cited by in corpus (2)

• A `Water Spout' Maser Jet in S235AB-MIR
• Evolution of the Water Maser Expanding Shell in W75N VLA 2