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A birth and growth of a collimated molecular jet from an AGB star

Hiroshi Imai·Philip J. Diamond
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Abstract

With the VLBA, we have observed water masers associated with the OH/IR star, W43A, which trace a birth and growth of a molecular jet. The water masers exhibit the collimated distribution (1700 AU: 20 AU) and fast motions (+/-150 km/s). The maser distribution was well fit by a precessing jet model. The jet length has extended by 800 AU within 8 years, indicating that the extension rate is roughly equivalent to the jet speed (150 km/s). Very likely the jet was born around the year 1960. An elongated planetary nebula will be formed by such a jet during an extremely short period (<<1000 yrs) of the transition to form a ptoto-planetary nebula. Then fading of the water maser jet will be observed during our human life.

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Hiroshi Imai, Philip J. Diamond. 2003-09-25. A birth and growth of a collimated molecular jet from an AGB star. https://arxiv.org/abs/astro-ph/0309682

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