Gas and Dust Associated with the Strange, Isolated Star BP Piscium
Abstract
We have carried out a multiwavelength observational campaign demonstrating some of the remarkable properties of the infrared-bright variable star BP Psc. Surrounded by a compact dusty, gaseous disk, this little-studied late G (or early K) type star emits about 75% of its detected energy flux at infrared wavelengths. Evidence for accretion of gas in conjunction with narrow bipolar jets and Herbig-Haro objects is apparently consistent with classification of BP Psc as a pre-main-sequence star, as postulated in most previous studies. If young, then BP Psc would be one of the nearest and oldest known classical T Tauri stars. However, such an evolutionary classification encounters various problems that are absent or much less severe if BP Psc is instead a luminosity class III post-main-sequence star. In this case, it would be the first known example of a first-ascent giant surrounded by a massive molecular disk with accompanying rapid gas accretion and prominent jets and HH objects. In this model, the genesis of the massive dusty gaseous disk could be a consequence of the envelopment of a low-mass companion star. Properties in the disk may be conducive to the current formation of planets, a gigayear or more after the formation of BP Psc itself.
- Publication:
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The Astrophysical Journal
- Pub Date:
- August 2008
- DOI:
- 10.1086/587448
- arXiv:
- arXiv:0802.0226
- Bibcode:
- 2008ApJ...683.1085Z
- Keywords:
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- planetary systems: protoplanetary disks;
- stars: general;
- Astrophysics
- E-Print:
- Accepted for Astrophysical Journal New version with minor changes: includes fixing a typo on the 3rd line of the paragraph that follows Equa 4 and adding a new reference (Nordhaus and Blackman 2006)