Gamma rays are actually not associated with any color that we can see. This is because gamma rays are a form of electromagnetic radiation with a very short wavelength, much shorter than that of visible light.
To understand this better, it’s important to know that visible light is just a small part of the electromagnetic spectrum, which includes radio waves, microwaves, infrared radiation, ultraviolet rays, X-rays, and gamma rays. Our eyes are only sensitive to wavelengths between approximately 400 and 700 nanometers, which we perceive as colors from violet to red.
Gamma rays, on the other hand, have wavelengths less than 0.01 nanometers. Because their wavelengths are so much shorter than those of visible light, they fall outside the range of human vision. Thus, while we can detect their presence through instruments, we cannot see gamma rays, and they have no color in the way that we typically understand it.
In summary, gamma rays exist well outside the visible spectrum, so they are colorless to the human eye.