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IRAS 19190+1102: A New Water Fountain PPN. Fonda Day (UNM), Ylva Pihlstrom (UNM), Mark Claussen (NRAO), & Raghvendra Sahai (JPL/Caltech). Water Fountain Pre-Planetary Nebulae (PPNs). In transition from asymptotic giant branch (AGB) to planetary nebula (PN)
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IRAS 19190+1102: A New Water Fountain PPN Fonda Day (UNM), Ylva Pihlstrom (UNM), Mark Claussen (NRAO), & Raghvendra Sahai (JPL/Caltech)
Water Fountain Pre-Planetary Nebulae (PPNs) • In transition from asymptotic giant branch (AGB) to planetary nebula (PN) • Highly red- and blue-shifted OH & H2O maser emission (v>50 km s-1) • Bipolar distribution of masers • Dynamical ages: t~100 yrs • Five bona fide + several candidates
Further Motivation • Obtain distances using trigonometric parallax • Motion of masers relative to source • Peculiar motion of source within galaxy • Parallax • Thesis project
IRAS 19190+1102 • OH & H2O emission first detected by Likkel (1989), v>70 km s-1 • Classifications: • PN • Young stellar object (YSO) • PPN
MSX Quads Sevenster (2002) Suarez, Gomez, & Miranda (2008)
VLBA Observations • H2O 22 GHz • 2 epochs: March 2004, May 2006 • ton-source=3.5 hr • =20-40 mJy/channel; detections >10 • Measured positions relative to reference maser
“Central” Maser Features Episodic or precessing jet?
Conclusions • IRAS 19190+1102 a true water fountain PPN • Evolved object • High velocity separation of maser emission • Bipolar, collimated jet-like outflows • Characteristics typical of other known water fountain nebulae
Future Work • Use multi-epoch VLBA observations to obtain distance • Distance measurement will give • Progenitor mass • Mass-loss rate • Luminosity