Related by context. Frequent words. (Click for all words.) 66 tracer 50 lasers 49 laser pulses 48 tracer bullets 48 fluorescent dye 47 fluorescence 47 laser 47 ionization 46 muzzle flashes 46 bioluminescent 46 infrared laser 46 spectrometry 45 fluorescent dyes 45 magnetic nanoparticles 45 phosphors 44 spectroscopy 44 fluorescent 44 spectra 44 muon 44 laser beam 43 laser pulse 43 strobes 43 infrared 43 multispectral 43 laser beams 43 femtosecond laser 43 interferometry 43 microbubbles 42 synchrotron radiation 42 gamma ray 42 spectroscopic 42 gamma rays 42 ultraviolet light 42 X ray beam 42 positrons 42 positron 42 ionized gas 41 florescent 41 muons 41 X ray emission 41 photometric 41 electron beams 41 fluoresce 41 laser ablation 41 fluorescence imaging 41 Raman spectroscopy 40 Fluorescence 40 reticle 40 quantum dots 40 searchlights 40 gel electrophoresis 40 photonic crystals 40 confocal microscopy 40 neutron 40 phosphorescent 40 neutrons 40 detectors 40 gamma radiation 40 ion beam 40 FRET 39 lasing 39 Terahertz 39 fluorescent proteins 39 ultra violet light 39 flares 39 infrared spectrometer 39 bioluminescence 39 strobe 39 starbursts 39 cosmic ray 39 photoreceptor 39 microscopy 39 smoke plumes 39 luminescent 39 incendiary bombs 39 optical telescopes 39 CMEs 39 infra red 38 femtosecond 38 phosphor 38 photonic crystal 38 particle 38 electron beam 38 holograms 38 detonation cord 38 pulsed 38 quasar 38 wavelengths 38 fluorescence microscopy 38 illumination 38 photon 38 Quantum dots 37 spectrophotometer 37 electrophoresis 37 accretion disk 37 waveguides 37 ultraviolet 37 nano particles 37 atomic particles 37 photons 37 spectrometer