THE STUDY OF PHOTOMETRIC VARIABILITY OF 7 PLANETARY-NEBULAE IN 1989-1993

Authors
ARKHIPOVA VP KOSTYAKOVA EB NOSKOVA RI
Citation
Vp. Arkhipova et al., THE STUDY OF PHOTOMETRIC VARIABILITY OF 7 PLANETARY-NEBULAE IN 1989-1993, Astronomy letters, 20(1), 1994, pp. 99-103
Citations number
11
Categorie Soggetti
Astronomy & Astrophysics
Journal title
Astronomy letters → ACNP
ISSN journal
10637737
Volume
20
Issue
1
Year of publication
1994
Pages
99 - 103
Database
ISI
SICI code
1063-7737(1994)20:1<99:TSOPVO>2.0.ZU;2-W
Abstract
A catalog of photometric observations of seven planetary nebulae - NGC 6572, IC 4997, Hu 2-1, NGC 6891, NGC 6720, IC 3568, and NGC 6543 - ma de in 1989 - 1993 is presented. The integral ubv-magnitudes are given. The average accuracy of the catalog is sigma(v) = O.009m, sigma(b) = 0.009m, and sigma(u) = 0.012m. The catalog is an extension of Kostyako va's catalogs [1, 2] and shows die photometric behavior of the nebulae from 1968 - 1993. Five nebulae are variable within O.2m - 0.6m. The p hotometric and spectral variations, observed for the young star-like p lanetary nebula IC 4997, reflect changes in the radiation field of the exciting star.