Particle detection systems and methods are disclosed. In one embodiment, a particle detection system comprises an incident beam light source that emits an incident beam, a particle interrogation zone disposed in the path of the incident beam, a photodetector disposed to detect the incident beam after passing through the particle interrogation zone, a pump beam light source for emitting a pump beam, the pump beam being targeted at the particle interrogation zone, wherein the incident beam, the pump beam, and photodetector are arranged such that the photodetector is configured to detect a combination of light from the incident beam, scattered light due to incident beam scattering in the particle interrogation zone, and scattered light due to pump beam scattering in the particle interrogation zone.