Spectroscopic Study of Four Members of Balmer Series in Be Stars

Abstract

The present work is a part of our on-going “International Observing Campaign” to observe large number of bright Be stars. The spectra of Be stars is characterized mainly by the presence of emission lines in the central part of the first few members of the Balmer series of Hydrogen. Sometimes, these emission lines show no reversal; and on occasions central emission may get split up midway into two components by a depression, giving a double peaked shape. This emission at Balmer series may continue up to about H15 and even more; and after that absorption lines occur like normal B-star. In this communication we report the spectroscopic analysis of four members of Balmer series of Hydrogen in four Be stars. It is found that all the four Be stars show Hα line strongly in emission. Three stars show Hβ, Hγ, Hδ strongly in absorption with weak emission components. Only one star shows Hβ also strongly in emission with two components lying over the underlying absorption. We have also measured the parameter of the lines like: equivalent width (W).