Proper motion of thermal sources in star-forming regions
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Proper motion of thermal sources in star-forming regions Laurent Loinard Centro de Radioastronomía y Astrofísica, UNAM Morelia, Michoacán Collaborators: Luis F. Rodriguez, Laura Gomez, Susana Lizano Claire Chandler, Crystal Brogan Paul Ho, David Wilner
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Proper motion of thermal sources in star-forming regions. Laurent Loinard. Centro de Radioastronomía y Astrofísica, UNAM. Morelia, Michoacán. Collaborators: Luis F. Rodriguez, Laura Gomez, Susana Lizano Claire Chandler, Crystal Brogan Paul Ho, David Wilner. IRAS 16293-2422…. - PowerPoint PPT Presentation
Transcript of Proper motion of thermal sources in star-forming regions
Proper motion of thermal sources in star-forming regionsLaurent LoinardCentro de Radioastronomía y Astrofísica, UNAMMorelia, Michoacán
Collaborators:
Luis F. Rodriguez, Laura Gomez, Susana Lizano
Claire Chandler, Crystal Brogan
Paul Ho, David Wilner
IRAS 16293-2422…
Mizuno et al. 1990
Low luminosity (L = 20 Lsun).
Class 0 source (age a few 104 yrs)
First recognized protobinary system
Proper motions…
Loinard 2002
Proper motions…
Chandler et al. 2005
So…
A hierarchical proto-triple system or a strongly precessing jet?
Loinard et al. 2007??
Pech et al., in prep
Pech et al., in prep
Jet orientation…
Hirano et al. 2001
IRAS 16293-2422 is a triple system that just ejected a pair of gas blobs.
First time such an ejection is observed ‘live’: we have witnessed the very birth of an HH pair.
It is the youngest known triple system.
Proper motions will eventually allow the determination of the masses of all the components
Forthcoming observations will allow us to study with unprecedented detail the evolution of the ejecta.
Conclusions on IRAS16293:
O’Dell & NASA (WFPC)
(NICMOS 2.12 microns Schultz et al. 2000)
Orion…
KL flow
Orion…
Red = 2.12 m Green = 2.17 m Blue = 2.27 m
BN/KL…
Gezari et al. (2000)
(Shuping et al. 2004; Wilson et al. 2000)
At the VLA…
Motions…
Tan (2004)
BN ejected from 1C 4000 years ago.
(30 km/s)
But…
Rodriguez et al. 2005
BN moves to the NW at 27+/-1 km s-1.
I moves to the SE at 12+/-2 km s-1.
RS I
Gezari et al. (2000)
Going back in time
The two sources were (at least in projection) very near each other 500 yrs ago…
Actually, three sources…
Gomez et al. 2005, 2007
RS I
Gezari et al. (2000)
Going back in time
All three sources were (at least in projection) very near each other 500 yrs ago…
But 500 yrs is just about the age of the KL outflow (John Bally, private communication)…And the locus of the
position where the sources were very near the “origin” of the flow…
So… how is this related to the KL object?
Energetics…
• Kinetic energy of BN+I+’n’: approx 2 x 1047 ergs
• Total energy of the KL flow: approx 4 x 1047 ergs
• Energy liberated by a 1Msun + 20 Msun merger: approx 3 x 1048 ergs
No need for a merger really. Rapid accretion of a modest disk as a result of the dynamical encounter would be sufficient…
Conclusions on Orion…
• There is strong evidence that BN, I and ‘n’ were once members of a now-defunct multiple system.
• The dynamical decay of that system is very likely related to the existence of the KL flow.
Thanks to a 10-fold increase in continuum sensitivity, the EVLA will allow such studies to be made in dozens of young stellar sources.
The time dimension is very important to understand early stellar evolution.
The continuous spectral coverage will allow the detection of RRL (3D dynamics) and the determination of spectral index, and identification of emission mechanism.
