  The bright A-type metallic-line star o Peg was reported in the early 1990s to
have a surface magnetic field of ~2kG by analyzing the widths and strengths of
spectral lines. In respect that those old studies were of rather empirical or
approximate nature and the quality of observational data was not sufficient,
this problem has been newly reinvestigated based on physically more rigorous
simulations of line flux profiles, along with the observed equivalent widths
(W) and full-widths at half-maximum (h) of 198 Fe I and 182 Fe II lines
measured from the high-quality spectra. Given the Fe abundance derived from the
conventional analysis, theoretical W and h values calculated for various sets
of parameters were compared with the observed ones, which lead to the following
conclusion regarding <H> (mean field strength). (1) An analysis of W yielded
<H>~1-1.5kG from Fe II lines with the microturbulence of vt~1.5km/s. (2) A
comparison of h resulted in <H>~1.5-2kG as well as the projected rotational
velocity of vsini~5km/s. (3) Accordingly, the existence of mean magnetic field
on the order of <H>~1-2kG in o Peg was confirmed, which is almost consistent
with the consequence of the previous work.
