The Emission Line Universe: Galactic Sources of Emission Lines. Stephen S. Eikenberry University of Florida 22 November 2006. OUTLINE. Introduction Infrared Emission Lines Nebular Galactic Emission Line Sources Stellar Galactic Emission Line Sources Summary & Future Prospects.
The Emission Line Universe: Galactic Sources of Emission Lines
Stephen S. Eikenberry
University of Florida
22 November 2006
Example: Cepheus A
From Stanghellini & Kaler
Point-symmetry is pervasive…
Point-symmetry is usually associated with:
- A progressive variation in the direction of the outflows
Thus, point-symmetry indicates the presence of a
Bipolar, Rotating, Episodic Jet or Collimated Outflow ( BRET).
A few representative examples next …
Point-symmetry morphology--BRET kinematicsIn a true BRET morphology is reflected in its kinematics
There is a wide range of speeds in the COFsfrom a few tens to several hundred km/s….
MyCn18, first PN to break the ~500 km/s barrier…now other examples such as He 3-1475 and Mz 3…
However, their masses (~1028-29 g), kinetic energy (~1043-44 ergs) and mechanical power (~1033-34 ergs/s) still are poorly determined in most cases …
MHD models with magnetic axis tilted with respect to bipolar wind axis…
Mastrodemos & Morris 1999
Binary cores: COFs and axis-symmetry may be produced either by : -Wind accretion from AGB onto WD or MS companion
Wind accretion may produce bipolar COFs that explain plane – symmetry, such as in the case of M2-9 (Soker & Livio 2001)
Soker & Rappaport 2000
…or via RLOF after a CE phase where low mass secondary is destroyed during an unstable mass transfer process, forming an accretion disk…
Some expected implications of binary core on COFs
Accretion through RLOF is short-lived at end of AGB .