【摘要】 本文给出了用佘山40厘米折射望远镜测定的BD+11°2576和BD+18°683的三角视差.更多还原

【Abstract】 The trigonometric parallaxes of BD+11°2576 and BD+18°683 have been determined with the Z-sè 40cm refractor (f=6.9m, plate scale is 2.9.″89/mm, λ=-8~h04~m44.~s75, φ=+31°05′47.″6). Kodak 103a-0 spectroscopic emulsions were used for all the exposures without filter. These plates were measured with the PDS-1010MS microdensitometer at the Purple Mountain Observatory. The digital image centering of PDS measurements was by means of a circular two-dimensional Gaussian distribution fitting. After a pretreatment with the plate constant method a central overlapping solution of the target star and field stars was found with a rigorous non-iterative normal equation system, but an iterative scheme designed by one of authors (Wang) was applied in solving that system. We obtain that the relative parallaxes of BD+11°2576 and BD+18°683 are 0.″1355±0.″0048 and 0.″1255±0.″0052 (internal standard errors), respectively, with the external standard errors, ±0.″0111 and ±0.″0116, estimated from the parallax values of constraint stars. The corrections to the absolute parallaxes are from van Altena’s table. Our absolute parallaxes of those stars are 0.″1398 and 0.″1283, respectively. We also obtain the relative parallaxes 0.″0278±0.″0058 and 0.″0412±0.″0116 (internal standard errors) for BD+11°2574 and AC+19°1513 210 in the same areas. For BD+18°685, which was determined with a significant relative parallax of 0.″0271±0.″0057 by Van Vleck Observatory, we obtain a discrepant value of 0.″0117±0.″0042.更多还原