38 citations · 196 across the 12 of their papers we have counts for
10 papers · 1 filter
Shaping the envelope of the asymptotic giant branch star W43A with a collimated fast jet
Daniel Tafoya, Hiroshi Imai, Jose F. Gomez +3
One of the major puzzles in the study of stellar evolution is the formation process of bipolar and multi-polar planetary nebulae. There is growing consensus that collimated jets cr…
AGB and post-AGB objects in the outer Galaxy
Ryszard Szczerba, Bosco H. K. Yung, Marta Sewiło +2
We present the results of our search for low- and intermediate mass evolved stars in the outer Galaxy using AllWISE catalogue photometry. We show that the [3.4]-[12] versus [4.6]-[…
Do Water Fountain Jets Really Indicate the Onset of the Morphological Metamorphosis of Circumstellar Envelopes?
Bosco H. K. Yung, Jun-ichi Nakashima, Chih-Hao Hsia +1
The small-scale bipolar jets having short dynamical ages from "water fountain (WF)" sources are regarded as an indication of the onset of circumstellar envelope morphological metam…
Wide Field CO Mapping in the Region of IRAS 19312+1950
Jun-ichi Nakashima, Dmitry A. Ladeyschikov, Andrej M. Sobolev +3
We report the results of a wide field CO mapping in the region of IRAS 19312+1950. This IRAS object exhibits SiO/HO/OH maser emission, and is embedded in a chemically-rich mole…
Methanol Observation of IRAS 19312+1950: A Possible New Type of Class I Methanol Masers
Jun-ichi Nakashima, Andrej M. Sobolev, Svetlana V. Salii +3
We report the result of a systematic methanol observation toward IRAS 19312+1950. The properties of the SiO, H2O and OH masers of this object are consistent with those of mass-losi…
Maser and Infrared Studies of Oxygen-Rich Late/Post-AGB Stars and Water Fountains: Development of a New Identification Method
Bosco Yung, Jun-ichi Nakashima, Christian Henkel
We explored an efficient method to identify evolved stars with oxygen-rich envelopes in the late AGB or post-AGB phase of stellar evolution, which include a rare class of objects -…
Water Maser Survey on AKARI and IRAS Sources: A Search for "Low-Velocity" Water Fountains
Bosco Yung, Jun-ichi Nakashima, Hiroshi Imai +3
We present the results of a 22GHz H2O maser survey toward a new sample of AGB and post-AGB star candidates. Most of the objects are selected for the first time based on the AKARI d…
Maser Observations of Westerlund 1 and Comprehensive Considerations on Maser Properties of Red Supergiants Associated with Massive Clusters
Thomas K. T. Fok, Jun-ichi Nakashima, Bosco H. K. Yung +2
We report the results of Australia Telescope Compact Array (ATCA) observations of the Westerlund~1 (Wd1) region in the SiO v=1, J=1-0 and H2O 6(16)-5(23) maser lines, and we also r…
CO Structure of the 21 Micron Source IRAS 22272+5435: A Sign of a Jet Launch?
Jun-ichi Nakashima, Nico Koning, Nikolaus H. Volgenau +3
We report the results of radio interferometric observations of the 21-micron source IRAS 22272+5435 in the CO J=2-1 line. 21-micron sources are carbon-rich objects in the post-AGB…
High Velocity Precessing Jets from the Water Fountain IRAS 18286-0959 Revealed by VLBA Observations
Bosco Yung, Jun-ichi Nakashima, Hiroshi Imai +3
We report the results of multi-epoch VLBA observations of the 22.2GHz water maser emission associated with the "water fountain" IRAS 18286-0959. We suggest that this object is the…