摘要
对于快速自转的恒星,谱线的等值宽度(EW)受引力昏暗效应的影响,即使自转速度达到临界也是很小的;而谱线半宽(FWHM)受引力昏暗效应影响相对较大,在(ω≈0.99)时,相对变化达到8%.对于光谱型在B0~B9范围内的主序星,谱线半宽的相对变化在自转速度较小时(ω<0.8)与光谱型无关;在自转速度较大时(ω≈0.99),谱线半宽的相对变化随光谱次型的增加而下降.
For rapidly rotating stars, the effect of gravity darkening on the equivalent width (EW)of spectral lines is very small, even when the rotation velocity is close to the critical velocity.But the effect on the full-width at half-maximum (FWHM) is relatively strong. At 0.99,the variation is 8%. For main-sequence stairs in the range of spectral type B0 to B9, thevariation of FWHM is almost independent of the spectral type when the rotation is small( < 0.8); for rapidly rotators ( 0.99), the percentage variation of FWHM decreaseswith advancing spectral subclass.