J/A+AS/128/573 J/A+AS/128/573 ubvy{Delta}a photometry of Renson stars H M Maitzen R Pressberger E Paunzen Astron. Astrophys. Suppl. Ser. 128 573 1998 1998A&AS..128..573M III/162 : General Catalogue of Ap and Am stars (Renson+ 1991) Photometry, uvby Stars, Am Stars, Ap stars: chemically peculiar stars: early-type Results of 131 stars from Renson's (1991, Cat. <III/162>) catalogue of Ap and Am stars observed with the {Delta}-a system are presented. With few exceptions the probability division of Renson for membership in the CP2 group of peculiar stars is nicely reflected by peculiar values of {Delta}-a. Comparison with already available {Delta}-a values yields slightly larger values due to a minor shift in the g_1_ filter sampling the depression. For a description of the {Delta}-a and Stroemgren photometric system, see e.g. <GCPD/75> and <GCPD/04>, respectively.

RNS Rensons number, as in Cat. <III/162> --- HD HD number (Cat. <III/135>) --- d(b-y) Difference of (b-y)_obs_ to the published values mmag d(m1) Difference of (m1)_obs_ to the published values mmag d(c1) Difference of (c1)_obs_ to the published values mmag CP CP class --- Nobs Number of nights --- RNS Rensons number, as in Cat. <III/162> --- HD HD number (Cat. <III/135>) --- Vmag mag(V) from Renson (1991, Cat. <III/162>) mag b-y Observed b-y mmag e_b-y Error of b-y mmag m1 Observed m1 mmag e_m1 Error of m1 mmag c1 Observed c1 mmag e_c1 Error of c1 mmag Da Observed {Delta}a mmag e_Da Error of {Delta}a mmag SpType Spectral type from Renson (1991, Cat. <III/162>) --- Patricia Bauer CDS 1998Feb05Ernst Paunzen <ernst@tycho.ast.univie.ac.at> J_A+AS_128_573.xml