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تسجيل مستخدم جديدCO Structure of the 21 Micron Source IRAS 22272+5435: A Sign of a Jet Launch?
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Jun-ichi Nakashima
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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 phase of evolution which show an unidentified emission feature at 21 micron. Since 21-micron sources usually also have circumstellar molecular envelopes, the mapping of CO emission from the envelope will be useful in tracing the nebular structure. From observations made with the Combined Array for Research in Millimeter-wave Astronomy (CARMA), we find that a torus and spherical wind model can explain only part of the CO structure. An additional axisymmetric region created by the interaction between an invisible jet and ambient material is suggested.
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