Reduction of the binary stars Δm measurements, obtained with the speckle interferometer of BTA of SAO RAS, into the standard photometric system

Abstract

For magnitude difference, measured with the speckle interferometer of the 6m telescope of SAO RAS, corrections for transformation from interferometer's photometric system into standard Johnson-Cousins V R I bands are calculated. The reduction accuracy is 0.01^m - 0.02^m. To determine the correction one has to know the magnitude difference in the V band or in the interferometer filter close to it with λ_eff = 545nm and the total color index of the system (V-I). The systematic difference of the obtained Δm from its real value is estimated by comparison with Hipparcos measurements.