A SPECTROSCOPIC AND PHOTOMETRIC STUDY OF THE PLANETARY NEBULAE Kn 61 AND Pa 5

作者：Garcia Diaz Ma T^*; Gonzalez Buitrago D; Lopez J A; Zharikov S; Tovmassian G; Borisov N; Valyavin G

来源：Astronomical Journal, 2014, 148(3): 57.

DOI：10.1088/0004-6256/148/3/57

• ISM: kinematics and dynamics
• planetary nebulae: individual (Ku 61, Pa 5)
• techniques: imaging spectroscopy
• techniques: photometric

We present the first morpho-kinematical analysis of the planetary nebulae Kn 61 and Pa 5 and explore the nature of their central stars. Our analysis is based on high-resolution and medium-resolution spectroscopic observations, deep narrow-band imaging, and integral photometry. This material allows us to identify the morphological components and study their kinematics. The direct images and spectra indicate an absence of the characteristic [N II] and [S II] emission lines in both nebulae. The nebular spectrum of Kn 61 suggests a hydrogen deficient planetary nebula and the stellar spectrum of the central star reveals a hydrogen-deficient PG 1159-type star. The [0 in] position velocity diagram reveals that Ku 61 is a closed, empty, spherical shell with a thin border and a filamentary surface expanding at 67.6 km s(-1) and the shell is currently not expanding isotropically. We derived a kinematic age of similar to 1.6 x 10(4) yr for an assumed distance of 4 kpc. A photometric period of similar to 5.7(+/- 0.4) days has been detected for Kn 61, indicating the presence of a possible binary system at its core. A possible link between filamentary spherical shells and PG 1159-type stars is noted. The morphology of Pa 5 is dominated by an equatorial toroid and faint polar extensions. The equatorial region of this planetary nebula is expanding at 45.2 km s(-1). The stellar spectrum corresponds to a very hot star and is dominated by a steep blue rising continuum and He II, Balmer, and Ca II photospheric lines.

• 出版日期2014-9