... Let us first find out which way -- rise in spectral resolution with some loss in the S/N ratio or increase in the S/N ratio with a fixed spectral resolution -- is better for the purpose of reduction of equivalent width determination errors. ... N -- number of counts for 1 ? ... line equivalent width, . ... Thus if the spectral resolution is managed to be increased (i.e. to decrease )without loss in the number of counts falling at 1 ?, the equivalent width measurement error is then proportional to . ...

... As a result of BTA observations of 23 chemically peculiar stars with strong magnetic fields, it was found that in 22 of them the longitudinal magnetic field, measured from the hydrogen line cores are considerably lower (by about 1/3) than the value measured from metal lines in the same spectra. ... New approaches need to be developed in order to interpret the data. ... The Zeeman spectrum of a star with a strong magnetic field, 53 Cam. ...