Informace o publikaci

Photometric Stromgren-H beta Quantification for O and B Stars of Luminosity Class V



Rok publikování 2017
Druh Článek v odborném periodiku
Časopis / Zdroj Publications of the Astronomical Society of the Pacific
Fakulta / Pracoviště MU

Přírodovědecká fakulta

Klíčová slova stars: early-type; techniques: photometric; stars: fundamental parameters
Popis In any photometric system, the relationship between the spectral type and the intrinsic colors is fundamental for the photometric stellar classification and for a reliable derivation of stellar parameters. Such relationships are being constantly verified and improved based on larger and better samples. The capability of the Stromgren-H beta photometry to provide reddening-free quantities allows the classification of reddened stars over the entire spectral sequence. However, a detailed consistent tabulation of the uvby beta quantities for the O-B9 part of the main sequence is currently warranted. We combine spectral types and photometry from the literature to provide a new empirical tabulation of the intrinsic color b - y, color differences c(1), m(1), [c(1)] and [m(1)] and the H beta index for main-sequence (luminosity class V) stars of spectral types O4.5 through B9.5 in terms of spectral sub-types. Our survey is based on more than 1400 stars. We use the established c(1) versus b - y intrinsic line and the accepted reddening slopes to obtain dereddened quantities and then calculate their median values as a function of the spectral sub-type. The classification ability of the system in this spectral range is reliable and the photometric quantities are not affected by the stellar rotation.