High resolution spectroscopy of the nuclei of the bipolar planetary nebulae M 2-9 and M 1-91
Por:
Arrieta, A, Torres-Peimbert, S
Publicada:
1 ene 2000
Resumen:
We have analyzed high resolution echelle spectra of the nuclei of the
young planetary nebulae M2-9 and M1-91. In M2-9 there is a well defined
negative gradient of ionization potential, electron density, electron
temperature and gas pressure with radial velocity. This behavior can be
interpreted as a negative gradient in these parameters with distance to
the exciting star. M1-91 shows a similar behavior. For M2-9 and M1-91
the intensity of Ha is higher than expected under photoionized
conditions. We suggest that shock excitation populates the lower levels
of hydrogen. Both objects show extremely wide wings in Her (of several
10(3) km s(-1)). We attribute these extended wings to electron
scattering. These observations support the interacting stellar winds
model.
Filiaciones:
Arrieta, A:
(Corresponding Author), Univ Nacl Autonoma Mexico, Inst Astron, Apartado Postal 70-264,Cd Univ, Mexico City 04510, DF, Mexico
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