Аңдатпа
A Fabry-Perot spectrometer was used to map the H II region around the O star ξ Per in the Hβ emission line. The angular size of the region is $$9_.^ \circ 1 \times 6_.^ \circ 0$$ . The region-boundary contour drawn at the double background level is centered on the star. The accuracy of our emission intensity measurements is 0.2 rayleigh. The proximity of the nebula NGC 1499 has virtually no effect on the measured emission measure toward the star. The star excitation parameter derived from observations corresponds to the spectral type O7.5 III and is U(Sp)=56.0±8.4 pc cm−2; the mean electron density in the region is n e=3.1±0.4 cm−3.