Additivity failure of chromatic valence in the opponent-color theory

The additivity of flicker responses produced by two different wavelengths λ₁ and λ₂ was investigated for five adapting levels of 560 nm by the summation-index method. A summation-index value of σ of 0.30 was obtained for all conditions employed, confirming the linear property of the achromatic channel. The additivity of unique chromatic responses, red, yellow, green, and blue, was also investigated with the same method. In this case the wavelengths λ₁ and λ₂ were chosen in a spectral region to produce one of the four unique colors and the summation index was measured for the color with the cancellation method. A summation index of 0.30 was found for the green and blue sensations and also for the red sensation if both stimuli were from the same spectral region. A slight additivity failure of the enhancement type was found for pairs λ₁ and λ₂ λ₁ was in the short-wavelength region while λ₂ was in the long-wavelength region. An additivity failure of the same type was found for the yellow chromatic sensation when λ₂ was 607 nm and λ₁ was 570, 550, or 533 nm, the last combination giving a summation index of as much as 0.64. The results imply the existence of two different cones whose responses do not add linearly to yield the yellow sensation.     

Quasi-ground,quasi-beta,and quasi-gamma bands

For even-even nuclei a list is presented of the probable members of quasi-ground, quasi-beta, and quasi-gamma bands of the spherical regions and the corresponding ground, beta, and gamma bands of the deformed regions. For simplicity the term “quasi” is used for both regions. References are given to the experimental data basic to the level assignments. The literature has been covered through November 1976.