Answer to Question #115082 in Astronomy | Astrophysics for tehmina

Question

what is rate of spontaneous emission to stimulated emission in sun??

Answer 1

There are two Einstein coefficients: A is related to spontaneous emission, B is related to stimulated emission. Being a hot star made of plasma, the Sun mostly emits spontaneously produced light. Excited ions spontaneously change their state to a lower one. The probability that a photon excites an ion so that it would emit another ion is too small. That is why without numerical values we can say that the rate of spontaneous emission to stimulated emission in sun is greater than unity.