thermal noise

Noise that occurs in a conductor or a semiconductor material due to random thermal motions of electrons in this material. As the temperature is raised, "thermal noise" is increased. Since this noise does not have frequency dependence but shows a flat spectrum, it is also called "white noise." To suppress this thermal noise, a semiconductor detector in an EDS or a YAG single-crystal scintillator in a slow-scan CCD camera is cooled.