The Stellar Space Distributions of dA and gK Stars

Abstract

AbstractWe present a case study on the stellar space distribution of stars with MK spectral types B8 to A2 (dA) and gG8 to gK2 (gK) in a sky region of 25 square degrees, centred at the galactic coordinate l = 4° and b = +12°. Two hundred and forty-eight (248) stars with MK type of B8–A2 and gG8–gK2 were identified in this field. The space density distributions of these stars were obtained by employing the Matrix and Malmquist methods. The relative density of B8–A2 stars tends to be similar to that of gG8–gK2 stars, which implies that the two groups of stars occupy the same space volume in the galaxy. The comparison with those of Field-3 (l = 0.8°, b = –10°) show that the space density distribution of the two groups of stars above and below the galactic plane is not the same. Above the galactic plane, the space density of the gK stars is higher than those of dA stars, whereas below the galactic plane the density of dA stars is higher than for the gK stars. For both groups, the maximum space density occurs at around 30–40 pc from the galactic plane.