Disk-Like Structure in the Semi-Regular Pulsating Star, X Her

Abstract

The author reports a result of an interferometric observation of the semiragular pulsating star with an unusual narrow molecular line profile, X Her, in the CO J=1-0 line with the Berkeley-Illinois-Maryland array. In the CO spectrum, a double-component profile (including narrow and broad components) is seen as reported by previous observations. The narrow component consists of two spiky peaks. The spatial structure of the board component shows bipolar shape, and that of the narrow component shows an elliptical/spherical shape. The two peaks in the narrow component show a systematic difference in the integrated intensity map. The kinematical and geometrical properties of the narrow component are reminiscent of a Keplerian rotating disk with the central mass of 0.9 M_sun, though an interpretation by an expansion disk seems to be more natural. A secondary bipolar flow instead of the disk cannot be fully excluded as an interpretation of the narrow line.

12 pages, 4 figues, accepted for publication in ApJ

References in corpus (4)

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• High velocity bipolar outflow and disk-like envelope in the carbon star V Hya
• Hipparcos red stars in the HpV_{T2} and VI_C systems
• Detection of Bipolar Flow toward an Unusual SiO Maser Source IRAS 19312+1950

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