THE STAR-FORMING REGION AROUND HH 24-26 - A REVISED MORPHOLOGY

Authors
Citation
Ag. Gibb et Bd. Heaton, THE STAR-FORMING REGION AROUND HH 24-26 - A REVISED MORPHOLOGY, Astronomy and astrophysics, 276(2), 1993, pp. 511-521
Citations number
31
Categorie Soggetti
Astronomy & Astrophysics
Journal title
ISSN journal
00046361
Volume
276
Issue
2
Year of publication
1993
Pages
511 - 521
Database
ISI
SICI code
0004-6361(1993)276:2<511:TSRAH2>2.0.ZU;2-N
Abstract
High resolution observations of the star-forming region around the Her big - Haro objects 24-26 have been made in J=4-3 HCO+, J=5-4 CS and J= 2-1 CO (resolutions 14'', 20'' and 22'' respectively). The former show that the gas appears to be clumped into small (0.05 pc), dense conden sations probably of several solar masses, some of which may be associa ted with known infrared sources. These clumps are embedded in a previo usly mapped molecular ridge. The HCO+ and CS lines show significant wi ngs in places highlighting the interaction between outflows and the su rrounding dense gas. Also resolved are two separate, roughly parallel bipolar outflows, with projected maximum velocities of 8 and 18 km s-1 for the north and south outflows respectively. The mass of material i n each outflow is calculated (in the optically thin limit) to be rathe r similar at about 0.5M., somewhat smaller than previous estimates. Op tical depth effects may explain this. A third CO flow may also be pres ent, roughly centred on HH 25 and probably associated with the largest HCO+ clump. None of the remaining clumps are situated near the centre s of the main outflows and it seems unlikely that these are powered by any previously known infrared object.