collisional broadening

Collisional broadening occurs when atoms or molecules in a gas collide with each other, causing their energy levels to fluctuate. These collisions disturb the precise frequencies at which atoms emit or absorb light, resulting in a wider spectral line than it would be if the particles were isolated. Essentially, the frequent interactions caused by collisions blur the clear-cut energy states, leading to a broader, less sharply defined spectral feature. This effect is more prominent at higher pressures where collisions happen more often, influencing how we interpret the spectral signals in scientific observations and applications.