Angular Diameters of Compact Planetary Nebulae
Abstract
We have obtained Hα CCD images of 21 compact planetary nebulae in the galactic bulge. All objects are resolved and, after deconvolving the seeing disk, we find diameters of 1--2'' with typical uncertainties of 20\%. The values are generally in good agreement with radio measurements but are smaller than older optical measurements. Based on the new values, we find that the Shklovsky method for distance determination greatly overestimates the actual distance for all of our objects.
0
Turn this paper into a full lesson
ArcXiv compiles a staged curriculum from this paper: 8-12 lessons across beginner → advanced, synthesised section guides, visuals, flashcards, a quiz, exercises, and on-demand deep dives per section. Grounded in the abstract, never invented.