The Spatial Distribution of O–B5 Stars in the Solar Neighborhood as Measured by [ITAL]HIPPARCOS[/ITAL][ITAL]Hipparcos[/ITAL]

Open Access
Publisher Website
Google Scholar
Abstract
We have developed a method to calculate the fundamental parameters of the vertical structure of the Galaxy in the solar neighborhood from trigonometric parallaxes alone. The method takes into account Lutz-Kelker–type biases in a self-consistent way and has been applied to a sample of O–B5 stars obtained from the Hipparcos catalog. We find that the Sun is located 24.2 ± 1.7 (random) ± 0.4 (systematic) pc above the Galactic plane and that the disk O–B5 stellar population is distributed with a scale height of 34.2 ± 0.8 (random) ± 2.5 (systematic) pc and an integrated surface density of [1.62 ± 0.04 (random) ± 0.14 (systematic)] × 10-3 stars pc-2. A halo component is also detected in the distribution and constitutes at least ≈5% of the total O–B5 population. The O–B5 stellar population within ~100 pc of the Sun has an anomalous spatial distribution, with a less than average number density. This local disturbance is probably associated with the expansion of the Gould Belt.

This publication has 13 references indexed in Scilit: