ar X iv : 0 80 5 . 17 30 v 1 [ as tr o - ph ] 1 2 M ay 2 00 8 Discovery of an H i Counterpart to the Extended Tail of Mira
نویسنده
چکیده
We report the detection of an H i counterpart to the extended, far-ultravioletemitting tail associated with the asymptotic giant branch star Mira (o Ceti). Using the Nançay Radio Telescope (NRT), we have detected emission as far as 88 north of the star, confirming that the tail contains a significant atomic component (MHI ∼ 4× 10 −3 M⊙). The NRT spectra reveal a deceleration of the tail gas caused by interaction with the local interstellar medium. We estimate an age for the tail of ∼ 1.2× 10 years, suggesting that the mass-loss history of Mira has been more prolonged than previous observational estimates. Using the Very Large Array (VLA) we have also imaged the H i tail out to ∼ 12 (0.4 pc) from the star. The detected emission shows a “head-tail” morphology, but with complex substructure. Regions with detected H i emission correlate with farultraviolet-luminous regions on large scales, but the two tracers are not closely correlated on smaller scales ( <∼1 ). We propose that detectable tails of H i are likely to be a common feature of red giants undergoing mass-loss. Subject headings: stars: AGB and post-AGB – stars: Individual (Mira AB) — stars: winds, outflows – radio lines: stars
منابع مشابه
ar X iv : 0 70 5 . 31 13 v 1 [ as tr o - ph ] 2 2 M ay 2 00 7 Dynamics and planet formation in / around binaries
1 Dipartimento di Fisica, Via Marzolo 8, 35131 Padova, Italy [email protected] 2 Observatoire de Paris, Section de Meudon, F-92195 Meudon Principal Cedex, France [email protected] 3 Stockholm Observatory, Albanova Universitetcentrum, SE-10691 Stockholm, Sweden [email protected] 4 Planetary Science Institute, Tucson, Arizona [email protected] 5 Observatoire de la Côte d’Azur, Nice, F...
متن کاملar X iv : 0 70 5 . 32 58 v 1 [ as tr o - ph ] 2 2 M ay 2 00 7 Disks around Young Binary Stars
متن کامل
ar X iv : 0 80 5 . 42 30 v 1 [ as tr o - ph ] 2 8 M ay 2 00 8 1 Photometric survey for stellar clusters in the outer part of M 33
We present a catalog of 4780 extended sources from the outer field of M33. The catalog includes 73 previously identified clusters or planetary nebulae, 1153 likely background galaxies, and 3554 new candidate stellar clusters. The survey is based on deep ground-based images obtained with the MegaCam instrument on the CFHT telescope. We provide gri photometry for detected objects as well as estim...
متن کاملar X iv : 0 70 5 . 40 34 v 1 [ as tr o - ph ] 2 8 M ay 2 00 7 The cold gaseous halo of NGC 891
We present H I observations of the edge-on galaxy NGC 891. These are among the deepest ever performed on an external galaxy. They reveal a huge gaseous halo, much more extended than seen previously and containing almost 30% of the H I. This H I halo shows structures on various scales. On one side, there is a filament extending (in projection) up to 22 kpc vertically from the disk. Small (MHI ∼ ...
متن کامل