ATCA and Spitzer Observations of the Binary Protostellar Systems CG30 and BHR71

Xuepeng Chen; Ralf Launhardt; Tyler L. Bourke; Thomas Henning; Peter J. Barnes

doi:10.1086/589939

paper

ATCA and Spitzer Observations of the Binary Protostellar Systems CG30 and BHR71

arXiv:0805.1533 · doi:10.1086/589939

Abstract

We present interferometric observations with resolution of ~3 arcsecs of the isolated, low-mass protostellar double cores CG30 and BHR71 in the N2 $H + (1 - 0) l in e an d a t 3 mm d u s t co n t in uu m, u s in g t h e A u s t r a l ian T e l esco p e C o m p a c t A r r a y (A T C A) . T h er es u l t s a r eco m pl e m e n t e d b y in f r a r e dd a t a f r o m t h e S p i t z er S p a ce T e l esco p e . I n C G 30, t h e 3 mm d u s t co n t in uu mima g esr eso l v e tw oco m p a c t so u r ces w i t ha se p a r a t i o n o f 21.7 a r csecs (8700 A U) . I n B H R 71, s t r o n g d u s t co n t in uu m e mi ss i o ni s d e t ec t e d a tt h e p os i t i o n o f t h e mi d - in f r a r e d so u r ce I R S 1, w hi l eo n l y w e ak e mi ss i o ni s d e t ec t e df r o m t h eseco n d a r y mi d - in f r a r e d so u r ce I R S 2. A ss u min g o pt i c a l l y t hin 3 mm d u s t co n t in uu m e mi ss i o n, w e d er i v e h y d r o g e n g a s ma sseso f 0.05 - - 2.1$ M_\odot $f or t h e f o u r s u b - cor es . N 2 H + (1 - 0) l in ee mi ss i o ni s d e t ec t e d inb o t h C G 30 an d B H R 71, an d i ss p a t ia l l y a ssoc ia t e d w i t h t h e t h er ma l d u s t co n t in uu m e mi ss i o n . W e d er i v e t h e v e l oc i t y f i e l d s an df in d sy mm e t r i c v e l oc i t y g r a d i e n t s inb o t h so u r ces . A ss u min g t ha tt h ese g r a d i e n t s a r e d u e t ocor er o t a t i o n, w ees t ima t e t h es p ec i f i c an g u l a r m o m e n t aan d r a t i oso f r o t a t i o na l e n er g y t o g r a v i t a t i o na l e n er g y f or a l l cor es . W e a l so f in d t ha tt h e N 2 H + e mi ss i o ni ss t r o n g l y a f f ec t e d b y t h eo u t f l o w s, b o t hin t er m so f e n t r ainm e n t an d m o l ec u l e d es t r u c t i o n .$ Spitzer $ima g ess h o w t h e mi d - in f r a r e d e mi ss i o n f r o ma l l f o u r s u b - cor es . A l l f o u r so u r ces a pp e a r t o d r i v e t h e i r o w n o u t f l o w s . B a se d o n t h e A T C A an d$ Spitzer$ observations, we construct spectral energy distributions (SEDs) and derive temperatures and luminosities for all cores. Based on the morphology and velocity structure, we suggest that the sub-cores in CG30 were formed by initial fragmentation of a filamentary prestellar core, while those in BHR71 could originate from rotational fragmentation of a single collapsing protostellar core.

31 pages, 10 figures, to be published by ApJ in Sep. 2008

ATCA and Spitzer Observations of the Binary Protostellar Systems CG30 and BHR71

Abstract

References in corpus (13)

Cited by in corpus (39)