相关论文: Photon and Light Meson Production in Hadronic Z^0 …
The inclusive production of prompt photons with energy above 10 GeV is measured using the OPAL detector in hadronic Z^0 decays at LEP. In contrast to previous measurements, the prompt photons were not required to be isolated. The production…
The inclusive production of D*+- mesons in photon-photon collisions has been measured using the OPAL detector at LEP at e+e- centre-of-mass energies of 183 and 189GeV. The D* mesons are reconstructed in their decay to D0pi+ with the D0…
The inclusive production of charged hadrons in the collisions of quasi-real photons e+e- -> e+e- +X has been measured using the OPAL detector at LEP. The data were taken at e+e- centre-of-mass energies from 183 to 209 GeV. The differential…
The production of charged hadrons and K_s mesons in the collisions of quasi-real photons has been measured using the OPAL detector at LEP. The data were taken at e+e- centre-of-mass energies of 161 and 172 GeV. The differential…
Mass dependences of the total production rates per hadronic Z decay of all light-flavour hadrons measured so far at LEP are extrapolated to the zero mass limit (m=0) using phenomenological laws of hadron production related to the spin,…
This final analysis of hadronic and leptonic cross-sections and of leptonic forward-backward asymmetries in e+e- collisions with the OPAL detector makes use of the full LEP1 data sample comprising 161 pb^-1 of integrated luminosity and 4.5…
The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding…
The inclusive production rate of phi mesons from the decay of b hadrons produced in Z0 decays was measured to be Br(b->phi+X) = 0.0282+-0.0013(stat.)+-0.0019(syst.), using data collected by the OPAL detector at LEP.
The cross section for open-beauty production in photon-photon collisions is measured using the whole high-energy and high-luminosity data sample collected by the L3 detector at LEP. This corresponds to 627/pb of integrated luminosity for…
A first measurement is presented of exclusive photoproduction of $\rho^0$ mesons associated with leading neutrons at HERA. The data were taken with the H1 detector in the years $2006$ and $2007$ at a centre-of-mass energy of $\sqrt{s}=319$…
A first measurement is presented of exclusive photoproduction of $\rho^0$ mesons associated with leading neutrons at HERA. The data were taken with the H1 detector in the years $2006$ and $2007$ at a centre-of-mass energy of $\sqrt{s}=319$…
We present an observation at LEP of the production of chi_c2 mesons in the collisions of two quasi-real photons using the OPAL detector. The chi_c2 mesons are reconstructed in the decay channel Chi_c2 to J/psi gamma to l+l- gamma (with l=…
A first measurement is presented of exclusive photoproduction of $\rho^0$ mesons associated with leading neutrons at HERA. The data were taken with the H1 detector in the years 2006 and 2007 at a centre-of-mass energy of 319 GeV and…
The cross section of W-boson pair-production is measured with the L3 detector at LEP. In a data sample corresponding to a total luminosity of 629.4/pb, collected at centre-of-mass energies ranging from 189 to 209 GeV, 9834 four-fermion…
Inclusive production of $\mathrm{D^{*\pm}}$ mesons in two-photon collisions was measured by the L3 experiment at LEP. The data were collected at a centre-of-mass energy $\sqrt{s} = 189$ GeV with an integrated luminosity of $176.4…
We report on a measurement of hard photons (Eg>30 MeV) in the reaction Ar+Ca at 180A MeV at an energy in which photons from the decay of pi0 mesons are dominating. Simultaneous measurement with the TAPS spectrometer of the photon spectrum…
Inclusive non-diffractive photoproduction of rho(770)^0, K^*(892)^0 and phi(1020) mesons is investigated with the H1 detector in ep collisions at HERA. The corresponding average \gamma p centre-of-mass energy is 210 GeV. The mesons are…
The exclusive reaction $\gamma p \to p \pi^+ \pi^-$ was studied in the photon energy range 3.0 - 3.8 GeV and momentum transfer range $0.4<-t<1.0$ GeV$^2$. Data were collected with the CLAS detector at the Thomas Jefferson National…
Inclusive production of the f_0(980), f_2(1270) and \phi(1020) resonances has been studied in a sample of 4.3 million hadronic Z^0 decays from the OPAL experiment at LEP. A coupled channel analysis has been used for the f_0 in simultaneous…
Exclusive photoproduction of $\rho^0(770)$ mesons is studied using the H1 detector at the $ep$ collider HERA. A sample of about 900000 events is used to measure single- and double-differential cross sections for the reaction $\gamma p \to…