Bibcode
Pena, M.; Garcia-Rojas, J.; Flores-Duran, Sheila; Hernandez-Martinez, Liliana
Referencia bibliográfica
IAU General Assembly, Meeting #29, #2251026
Fecha de publicación:
8
2015
Número de citas
0
Número de citas referidas
0
Descripción
Spectroscopic data for 20 PNe in the irregular galaxy NGC6822 have been
studied. This represents 80% of the total sample of PNe candidates in
this galaxy. We discuss the kinematics of PNe in comparison to the
kinematics of the HI disk and the young and intermediate age
populations. In addition the chemical abundances of the sample have been
analyzed. We found that PNe can be separated in two groups: one older,
with 12+log O/H abundances lower than 7.8 and other young, with
abundances similar to the values of HII regions (12+log O/H of about
8.1). The old objets are more widely distributed than the young ones. In
our sample, a large fraction of PNe (near 30%) can be classified as
Peimbert Type I objects, fraction that is much larger than in our
galaxy. Many of our PNe are highly ionized, showing an abundance
fraction He++/He larger than 0.1. From the HeII 4686 A emission line we
have determined temperatures for the central stars founding that half of
them show T larger than 100000 K. These result are being analyzed in
terms of the possible populations for the PN sample.