The photoproduction of $D^{*pm} (2010)$ mesons associated with a leading neutron has been observed with the ZEUS detector in $ep$ collisions at HERA using an integrated luminosity of 80 pb$^{-1}$. The neutron carries a large fraction, {$x_L>0.2$}, of the incoming proton beam energy and is detected at very small production angles, {$theta_n<0.8$ mrad}, an indication of peripheral scattering. The $D^*$ meson is centrally produced with pseudorapidity {$|eta|<1.5$}, and has a transverse momentum {$p_{it T} > 1.9$ GeV}, which is large compared to the average transverse momentum of the neutron of 0.22 GeV. The ratio of neutron-tagged to inclusive $D^*$ production is $8.85pm 0.93({rm stat.})^{+0.48}_{-0.61}({rm syst.})%$ in the photon-proton center-of-mass energy range {$130
S. Chekanov, M. Derrick, D. Krakauer, J.H. Loizides 1, S. Magill, B. Musgrave, et al. (2004). Photoproduction of D*^pm Mesons Associated with a Leading Neutron. PHYSICS LETTERS. SECTION B, 590, 143-160 [10.1016/j.physletb.2004.03.076].
Photoproduction of D*^pm Mesons Associated with a Leading Neutron
BASILE, MAURIZIO;CIFARELLI, LUISA;CONTIN, ANDREA;PALMONARI, FEDERICO;SARTORELLI, GABRIELLA;ZICHICHI, ANTONINO;
2004
Abstract
The photoproduction of $D^{*pm} (2010)$ mesons associated with a leading neutron has been observed with the ZEUS detector in $ep$ collisions at HERA using an integrated luminosity of 80 pb$^{-1}$. The neutron carries a large fraction, {$x_L>0.2$}, of the incoming proton beam energy and is detected at very small production angles, {$theta_n<0.8$ mrad}, an indication of peripheral scattering. The $D^*$ meson is centrally produced with pseudorapidity {$|eta|<1.5$}, and has a transverse momentum {$p_{it T} > 1.9$ GeV}, which is large compared to the average transverse momentum of the neutron of 0.22 GeV. The ratio of neutron-tagged to inclusive $D^*$ production is $8.85pm 0.93({rm stat.})^{+0.48}_{-0.61}({rm syst.})%$ in the photon-proton center-of-mass energy range {$130I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
