Astronomy and Astrophysics – Astrophysics
Scientific paper
Jun 1993
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1993a%26a...273..221r&link_type=abstract
Astronomy and Astrophysics, Vol.273, NO. 1/JUNI, P. 221, 1993
Astronomy and Astrophysics
Astrophysics
169
Interstellar Medium: Jets And Outflows, Radio Continuum: Stars, Circumstellar Matter, Stars: Formation Of, Stars: Pre-Main Sequence
Scientific paper
We have observed 59 young stars associated with Herbig-Haro objects in the continuum at 1300 μm, and detected 53 of them, corresponding to the very high detection rate of 90%. The signals are generally large, of the order of several hundred milliJansky. High extinction sources have on average more than twice as large a flux as low extinction sources. Translating the 1300 μm measurements into total gas and dust masses, under appropriate assumptions, we find that Herbig-Haro energy sources are surrounded by considerable amounts of cold circumstellar material, typically in the range from a few tenths to several solar masses. We have additionally observed 14 sources at 870 μm, and derive a spectral index m = 1.0±0.4, assuming a typical dust temperature of 36K, determined by additionally employing IRAS data. Such a spectral index suggests either the presence of grains larger than in the interstellar medium and/or material with large optical depth. A comparison with 1300 μm fluxes of T Tauri stars from the literature shows that T Tauri stars and Herbig-Haro energy sources have very different distributions in a histogram of fluxes scaled to a given distance: the Herbig-Haro energy sources have fluxes more than an order of magnitude larger than the T Tauri stars. From their IRAS energy distributions it follows that almost all Herbig-Haro energy sources are class I sources. The large difference observed between Herbig-Haro energy sources and T Tauri stars thus suggests that the major changes in the circumstellar environment of a young low mass star occurs within its first few hundred thousand years, which is a likely upper limit for the age of class I sources. We observe a clear relation between bolometric luminosity and 1300 μm flux for our objects, suggesting that the more massive a circumstellar environment is, the larger is the accretion rate towards the star likely to be.
Chini Rolf
Kreysa Ernst
Krügel Endrik
Reipurth Bo
Sievers Albrecht
No associations
LandOfFree
Cold Dust around Herbig-Haro Energy Sources - a 1300-MICRON Survey does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Cold Dust around Herbig-Haro Energy Sources - a 1300-MICRON Survey, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cold Dust around Herbig-Haro Energy Sources - a 1300-MICRON Survey will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1732613