Physical Review C
015201 (15 pages)
The light vector mesons (ρ,ω, and ϕ) were produced in deuterium, carbon, titanium, and iron targets in a search for possible in-medium modifications to the properties of the ρ meson at normal nuclear densities and zero temperature. The vector mesons were detected with the CEBAF Large Acceptance Spectrometer (CLAS) via their decays to e+e−. The rare leptonic decay was chosen to reduce final-state interactions. A combinatorial background was subtracted from the invariant mass spectra using a well-established event-mixing technique. The ρ-meson mass spectrum was extracted after the ω and ϕ signals were removed in a nearly model-independent way. Comparisons were made between the ρmass spectra from the heavy targets (A>2) with the mass spectrum extracted from the deuterium target. With respect to the ρ-meson mass, we obtain a small shift compatible with zero. Also, we measure widths consistent with standard nuclear many-body effects such as collisional broadening and Fermi motion.
Original Publication Citation
Wood, M. H., Nasseripour, R., Weygand, D. P., Djalali, C., Tur, C., Mosel, U., . . . Collaboration, C. (2008). Light vector mesons in the nuclear medium. Physical Review C, 78(1), 015201. doi:10.1103/PhysRevC.78.015201
0000-0002-5648-0256 (Amayan), 0000-0003-1582-2376 (Dodge), 0000-0001-7282-8120 (Hyde), 0000-0003-2243-6836 (Kuhn), 0000-0001-5416-2900 (Weinstein)
Wood, M. H.; Amaryan, M. J.; Bagdasaryan, H.; Careccia, S. L.; Dharmawardane, K. V.; Dodge, G. E.; Gavalian, G.; Guler, N.; Hyde-Wright, C. E.; Juengst, H. G.; Kalantarians, N.; Klein, A.; Klimenko, K. V.; Kuhn, S. E.; Lachniet, J.; Niroula, M. R.; Niyazov, R. A.; Tkachenko, S.; Weinstein, L. B.; Zhang, J.; and CLAS Collaboration, "Light Vector Mesons in the Nuclear Medium" (2008). Physics Faculty Publications. 338.