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تسجيل مستخدم جديدNuclear dependence of light neutral meson production in p-A collisions at 400 GeV with NA60
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The NA60 experiment has studied low-mass muon pair production in proton-nucleus collisions with a system of Be, Cu, In, W, Pb and U targets, using a 400 GeV proton beam at the CERN SPS. The transverse momentum spectra of the $rho/omega$ and $phi$ mesons are measured in the full $p_mathrm{T}$ range accessible, from $p_mathrm{T} = 0$ up to 2 GeV/$c$. The nuclear dependence of the production cross sections of the $eta$, $omega$ and $phi$ mesons has been found to be consistent with the power law $sigma_mathrm{pA} propto mathrm{A}^alpha$, with the $alpha$ parameter increasing as a function of $p_mathrm{T}$ for all the particles, and an approximate hierarchy $alpha_eta approx alpha_phi > alpha_omega$. The cross section ratios $sigma_eta/sigma_omega$, $sigma_rho/sigma_omega$ and $sigma_phi/sigma_omega$ have been studied as a function of the size A of the production target, and an increase of the $eta$ and $phi$ yields relative to the $omega$ is observed from p-Be to p-U collisions.
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The NA60 experiment has studied low-mass muon pair production in proton-nucleus collisions with a system of Be, Cu, In, W, Pb and U targets using a 400 GeV/$c$ proton beam at the CERN SPS. The mass spectrum is well described by the superposition of t
he two-body and Dalitz decays of the light neutral mesons $eta$, $rho$, $omega$, $eta$ and $phi$. A new high-precision measurement of the electromagnetic transition form factors of the $eta$ and $omega$ mesons is presented, complemented with a measurement of the temperature parameter of the $rho$ meson in cold nuclear matter. The $pt$ spectra for the $omega$ and $phi$ mesons are extracted in the full $pt$ range accessible, up to $pt = 2$ GeV/$c$. The nuclear dependence of the production cross sections for the $eta$, $omega$ and $phi$ mesons has been investigated in terms of the power law $sigma_mathrm{pA} propto mathrm{A}^alpha$, and the $alpha$ parameter was studied as a function of $pt$.
The NA60 experiment has studied low-mass muon pairs production in proton-nucleus collisions at 400 GeV/$c$ at the CERN SPS. The mass spectrum is well described by the superposition of the two-body and Dalitz decays of the light neutral mesons $eta$,
$rho$, $omega$, $eta$ and $phi$. The large collected statistics allows to isolate the contributions due to the Dalitz decays of the $eta$ and $omega$ mesons, from which the electromagnetic transition form factors of the two mesons have been extracted. The found values agree with the previous available measurements, improving their uncertainty thanks to the higher statistics. The results thus confirm the discrepancy with the prediction of the Vector Meson Dominance model in the case of the electromagnetic form factor of the $omega$ meson.
Results are presented from data recorded in 2009 by the PHENIX experiment at the Relativistic Heavy Ion Collider for the double-longitudinal spin asymmetry, $A_{LL}$, for $pi^0$ and $eta$ production in $sqrt{s} = 200$ GeV polarized $p$$+$$p$ collisio
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The PHENIX experiment at the Relativistic Heavy Ion Collider has measured low mass vector meson, $omega$, $rho$, and $phi$, production through the dimuon decay channel at forward rapidity ($1.2<|y|<2.2$) in $p$$+$$p$ collisions at $sqrt{s}=200$ GeV.
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The PHENIX experiment at the Relativistic Heavy Ion Collider has measured the invariant differential cross section for production of K^0_S , omega, eta prime, and phi mesons in p + p collisions at = 200 GeV. Measurements omega and phi production in d
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