In my research field of high-energy heavy-ion collisions, plenty of omega mesons are created. The light vector mesons (##\rho##, ##\omega##, and ##\phi##) play a very important role in understanding the findings on "dileptons". Dileptons are simply electron-positron or muon-antimuon pairs. Plenty of those are created in a heavy-ion collision, and taking their invariant-mass spectra measures a quantity called the electromagnetic current-current correlation function of hadrons.
That's a very interesting signal to learn about the hot and dense medium created in high-energy heavy ion collisions, because the leptons (and also photons) don't take part in the strong interaction, and thus for them the hot and dense medium is transparent, i.e., the dileptons do not suffer final-state interactions but come out of the hot and dense fireball pretty undistorted and thus give a signal from the hot and dense interior.
Among the mechanisms to create dileptons in such collisions are also the decays of the light vector mesons, and thus by measuring the dilepton's invariant-mass spectra you can find out something about the change of the spectral properties of the light vector mesons. It turns out that models that predict a large broadening of the spectral function with quite small mass shifts describe all the data at a large varieties of collision energies pretty accurately.
In turn this tells as something about the mechanism underlying the restoration of the (approximate) chiral symmetry of the light-quark sector in QCD: It's a "melting of the resonances", i.e., the resonances become very broad around the transition between a hot and dense hadron gas and a state of matter, called the "Quark Gluon Plasma", which consists of a strongly coupled gas (or liquid?) of quarks and gluons. For a pretty recent review, see, e.g.,
R. Rapp, J. Wambach, H. van Hees, The Chiral Restoration Transition of QCD and Low Mass Dileptons
Landolt-Börnstein, Volume I/23, 4-1 (2010)
arXiv: 0901.3289 [hep-ph]
