Based on high resolution, low noise spectroscopy in the spectral regio
n from 4200 Angstrom to 6700 Angstrom we derived T-eff = 7900 +/- 200
K, log g = 4.2 +/- 0.15, nu sin(i) = 12.5 (-0.5, + 1.5)km s(-1), and e
lemental abundances for the rapidly oscillating (ro)Ap star alpha Cir(
HD 128898, HR5463). We used the spectrum synthesis and the equivalent
width technique and confirmed the presence of a magnetic field in alph
a Cir. The underabundance of C, N, and O, and the overabundances of ra
re-earth and some other heavy elements are comparable to other cool Ap
-stars. The most important peculiarity is that of Co, which is almost
as overabundant as Cr, the most overabundant iron peak element in cool
Ap-stars.