THE MANGANESE MERCURY STAR pi(1) BOOTIS.
High-dispersion plates secured with the Coudé spectrograph of the Lick 120 inch telescope have been used to analyze the peculiar A star pi(1) Bootis. Spectral-energy distribution measurements are combined with line-intensity data for iron and manganese in two stages of ionization to obtain a fit with model atmospheres for T(eff) = 13,000 degrees K and log g = 4. The influence of adopted T and g on the derived abundances is discussed. Although C, O, Mg, Si, Ti, Cr, and Fe appear to have nearly normal (i.e., solar) abundances, strontium appears to be enhanced in abundance by an order of magnitude, and scandium is about 50 times overabundant, while manganese and yttrium appear to be two orders of magnitude overabundant. If the identification of gallium is correct, this element is overabundant by a factor approaching 100,000; while if lambda3983.90 is to be attributed to HgII, as Bidelman suggests, the overabundance of this element is many orders of magnitude.
UNIVERSITY OF CALIFORNIA (LOS ANGELES).
J W
JW
Montgomery
L H
LH
Aller