The lines of He I are faint or absent in the dwarfs. The strongest enhanced lines of iron are faintly present in main-sequence stars and increase in strength with increasing luminosity. The hydrogen lines show a marked negative absolute-magnitude effect.
|C Hya....||A0 V||08:20||-03°35'||4.0||A0|
|UMa....||A0 V||11:48||+54 15||2.5||A0|
|a CrB....||A0 V||15:30||+27 03||2.3||A0|
|a Lyr......||A0 V||18:33||+38 41||0.1||A0|
|Cyg.....||A0 III||19:41||+44 53||3.0||A0||1|
|1. The hydrogen lines in Cygni have less pronounced wings than in the other stars listed. Dr. Kuiper has found that the measures of the visual system made during the last 30 years indicate a dynamical parallax of 0".013-0".018.|
The luminosity classification was made on the basis of the wings of the hydrogen lines.
|High resolution image|