| Published Articles | |
| Report number | arXiv:1608.07898 |
| Title | Precision study of the $\eta \to \mu \mu \gamma$ and $\omega \to \mu + \mu \mu \pi^0$ electromagnetic transition form-factors and of the $\rho \to \mu \mu$ line shape in NA60 |
| Related title | Precision study of the $\eta \to \mu \mu \gamma$ and $\omega \to \mu + \mu \mu \pi^0$ electromagnetic transition form-factors and of the $\rho \to \mu \mu$ line shape in NA60 |
| Author(s) |
Arnaldi, R. (INFN, Turin ; Turin U.) ; Banicz, K. (CERN ; Heidelberg U.) ; Borer, K. (Bern U.) ; Castor, J. (Clermont-Ferrand U.) ; Chaurand, B. (Ecole Polytechnique) ; Chen, W. (RIKEN BNL) ; Cicalò, C. (INFN, Cagliari ; Sassari U.) ; Colla, A. (INFN, Turin ; Turin U.) ; Cortese, P. (INFN, Turin ; Turin U.) ; Damjanovic, S. (CERN ; Heidelberg U.) ; David, A. (CERN ; Lisbon, CFP) ; de Falco, A. (INFN, Cagliari ; Cagliari U.) ; Devaux, A. (Clermont-Ferrand U.) ; Ducroux, L. (Lyon, IPN) ; En'yo, H. (Wako, RIKEN) ; Fargeix, J. (Clermont-Ferrand U.) ; Ferretti, A. (INFN, Turin ; Turin U.) ; Floris, M. (INFN, Cagliari ; Cagliari U.) ; Förster, A. (CERN) ; Force, P. (Clermont-Ferrand U.) ; Guettet, N. (CERN ; Clermont-Ferrand U.) ; Guichard, A. (Lyon, IPN) ; Gulkanian, H. (Yerevan Phys. Inst.) ; Heuser, J.M. (Wako, RIKEN) ; Jarron, P. (CERN) ; Keil, M. (CERN ; Lisbon, CFP) ; Kluberg, L. (Ecole Polytechnique) ; Li, Z. (RIKEN BNL) ; Lourenço, C. (CERN) ; Lozano, J. (Lisbon, CFP) ; Manso, F. (Clermont-Ferrand U.) ; Martins, P. (CERN ; Lisbon, CFP) ; Masoni, A. (INFN, Cagliari ; Cagliari U.) ; Neves, A. (Lisbon, CFP) ; Ohnishi, H. (Wako, RIKEN) ; Oppedisano, C. (INFN, Turin ; Turin U.) ; Parracho, P. (CERN ; Lisbon, CFP) ; Pillot, P. (Lyon, IPN) ; Poghosyan, T. (Yerevan Phys. Inst.) ; Puddu, G. (INFN, Cagliari ; Cagliari U.) ; Radermacher, E. (CERN) ; Ramalhete, P. (CERN ; Lisbon, CFP) ; Rosinsky, P. (CERN) ; Scomparin, E. (INFN, Turin ; Turin U.) ; Seixas, J. (Lisbon, CFP) ; Serci, S. (INFN, Cagliari ; Cagliari U.) ; Shahoyan, R. (CERN ; Lisbon, CFP) ; Sonderegger, P. (Lisbon, CFP) ; Specht, H.J. (Heidelberg U.) ; Tieulent, R. (Lyon, IPN) ; Uras, A. (INFN, Cagliari ; Cagliari U. ; Lyon, IPN) ; Usai, G. (INFN, Cagliari ; Cagliari U.) ; Veenhof, R. (Lisbon, CFP) ; Wöhri, H.K. (CERN ; INFN, Cagliari ; Cagliari U. ; Lisbon, CFP) |
| Publication | 2016-06-10 |
| Imprint | 2016-08-28 |
| Number of pages | 8 |
| In: | Phys. Lett. B 757 (2016) 437-444 |
| DOI | 10.1016/j.physletb.2016.04.013 |
| Subject category | Nuclear Physics - Experiment |
| Accelerator/Facility, Experiment | CERN SPS ; NA60 |
| Abstract | The NA60 experiment studied low-mass muon pair production in proton-nucleus (p-A) collisions using a 400 GeV proton beam at the CERN SPS. The low-mass dimuon spectrum is well described by the superposition of the two-body and Dalitz decays of the light neutral mesons $\eta$, $\rho$, $\omega$, $\eta'$ and $\phi$, and no evidence of in-medium effects is found. A new high-precision measurement of the electromagnetic transition form factors of the $\eta$ and $\omega$ was performed, profiting from a 10 times larger data sample than the peripheral In-In sample previously collected by NA60. Using the pole-parameterisation $|F(M)|^2 = (1 -M^2/\mathrm{\Lambda}^2)^{-2}$ we find $\mathrm{\Lambda}_\eta^{-2} = 1.934\ \pm\ 0.067$ (stat.) $\pm\ 0.050$ (syst.) (GeV/$c^2$)$^{-2}$ and $\mathrm{\Lambda}_\omega^{-2} = 2.223\ \pm\ 0.026$ (stat.) $\pm\ 0.037$ (syst.) (GeV/$c^2$)$^{-2}$. An improved value of the branching ratio of the Dalitz decay $\omega \to \mu^+\mu^-\pi^0$ is also obtained, with $BR(\omega \to \mu^+\mu^-\pi^0) = [1.41 \pm 0.09 \mathrm{(stat.)}$ $\pm 0.15 \mathrm{(syst.)}] \times 10^{-4}$. Further results refer to the $\rho$ line shape and a new limit on $\rho/\omega$ interference in hadron interactions. |
| Copyright/License | publication: © 2016-2024 The Author(s) (License: CC-BY-4.0), sponsored by SCOAP³ |
Corresponding record in: Inspire
Record created 2016-05-03, last modified 2022-08-10
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