901 citations · 2.4k across the 35 of their papers we have counts for
11 papers · 1 filter
Direct determination of the epicycle frequency in the galactic disk, and the derived rotation velocity V0
J. R. D. Lepine, Wilton S. Dias, Yuri Mishurov
We present a method which allows a direct measurement of the epicycle frequency in the galactic disk, using the large database on open clusters completed by our group. The obse…
Direct determination of the spiral pattern rotation speed of the Galaxy
W. S. Dias, J. R. D. Lépine
The rotation velocity of the spiral pattern of the Galaxy is determined by direct observation of the birthplaces of open clusters of stars in the galactic disk as a function of the…
Discovery of a young massive stellar cluster associated with IRAS source 16177-5018
Alexandre Roman-Lopes, Zulema Abraham, Jacques Raymond Daniel Lepine
We report the discovery of a young massive stellar cluster embedded in an extended HII region, invisible at optical wavelengths where the extinction is magnitudes,…
Formation scenarios for the young stellar associations between galactic longitudes l = 280-360 deg
Marilia J. Sartori, Jacques R. D. Lepine, Wilton S. Dias
We investigate the spatial distribution, the space velocities and age distribution of the pre-main sequence (PMS) stars belonging to Ophiuchus, Lupus and Chamaeleon star-forming re…
Using Cepheids to determine the galactic abundance gradient. III.First results for the outer disc
S. M. Andrievsky, V. V. Kovtyukh, R. E. Luck +3
As a continuation of our previous work, which concerned the radial abundance distribution in the galactic disc over the distances 4-10 kpc this paper presents the first results on…
Corotation: its influence on the chemical abundance pattern of the Galaxy
Yu. N. Mishurov, J. R. D. Lepine, I. A. Acharova
A simple theory for the chemical enrichment of the Galaxy which takes into account the effects of spiral arms on heavy elements output was developed. In the framework of the model…