IRC+10216's Innermost Envelope -- The eSMA's View

Details IRC+10216's Innermost Envelope -- The eSMA's View IRC+10216's Innermost Envelope -- The eSMA's View

2009-04-02

arxiv.org/abs/0904.0280v1

Astrophys.J.698:1924-1933,2009; Erratum-ibid.727:60,2011

Astronomy and Astrophysics

Astrophysics

Galaxy Astrophysics

26 pages, 8 figures, accepted for publication in The Astrophysical Journal. Please find the pdf at http://www.submm.caltech.

Scientific paper

10.1088/0004-637X/698/2/1924 10.

We used the Extended Submillimeter Array (eSMA) in its most extended configuration to investigate the innermost (within a radius of 290 R* from the star) circumstellar envelope (CSE) of IRC+10216. We imaged the CSE using HCN and other molecular lines with a beam size of 0."22 x 0."46, deeply into the very inner edge (15 R*) of the envelope where the expansion velocity is only 3 km/s. The excitation mechanism of hot HCN and KCl maser lines is discussed. HCN maser components are spatially resolved for the first time on an astronomical object. We identified two discrete regions in the envelope: a region with a radius of . 15 R*, where molecular species have just formed and the gas has begun to be accelerated (region I) and a shell region (region II) with a radius of 23 R* and a thickness of 15 R*, whose expansion velocity has reached up to 13 km/s, nearly the terminal velocity of 15 km/s. The Si$^{34}$S line detected in region I shows a large expansion velocity of 16 km/s due to strong wing components, indicating that the emission may arise from a shock region in the innermost envelope. In region II, the P.A. of the most copious mass loss direction was found to be 120 +/- 10 degrees, which may correspond to the equatorial direction of the star. Region II contains a torus-like feature. These two regions may have emerged due to significant differences in the size distributions of the dust particles in the two regions.

Affiliated with

Also associated with

No associations

Rating

IRC+10216's Innermost Envelope -- The eSMA's View 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 IRC+10216's Innermost Envelope -- The eSMA's View, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and IRC+10216's Innermost Envelope -- The eSMA's View will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-63292