相关论文: Meson Production Experiments with Electromagnetic …
The electromagnetic kaon production amplitudes associated to Lambda/Sigma hyperons can be described by phenomenological models, most notably by isobar approaches. Experimental data on kaon production have been collected at ELSA, SPring8,…
Pion photoproduction in the $\overrightarrow\gamma\overrightarrow p \to \pi^0 p$ reaction has been measured in the FROST experiment at the Thomas Jefferson National Accelerator Facility. In this experiment, circularly polarized photons with…
The LHC experiments are close to collecting collision data. An overview of first physics measurements of the W and Z production cross-sections is presented. The electron and muon decay channels are considered. Emphasis will be given to…
The $f_0$(1500) meson resonance is one of several contenders to have significant mixing with the lightest glueball. This resonance is well established from several previous experiments. Here we present the first photoproduction data for the…
The $\pi_1(1600)$, a $J^{PC} = 1^{-+}$ exotic meson has been observed by experiments using pion beams. Theorists predict that photon beams could produce gluonic hybrid mesons, of which the $\pi_1(1600)$ is a candidate, at enhanced levels…
The high-energy proton-proton collisions at the Large Hadron Collider provide the ideal conditions to study the rare processes predicted by the Standard Model (SM) such as the production of multiple electroweak bosons. These processes…
The CMS experiment at the Large Hadron Collider collected in the first months of operation a luminosity of about 300/nb. The first results in the context of the B physics obtained with these data are presented. The di-muon resonances from…
We report results of $\Lambda$ hyperon production in semi-inclusive deep-inelastic scattering off deuterium, carbon, iron, and lead targets obtained with the CLAS detector and the Continuous Electron Beam Accelerator Facility 5.014~GeV…
The observation of beam spin asymmetries in two-pion production in semi-inclusive deep inelastic scattering off an unpolarized proton target is reported. The data presented here were taken in the fall of 2018 with the CLAS12 spectrometer…
The COMPASS Experiment at the CERN SPS has a broad physics program focused on the nucleon spin structure and on hadron spectroscopy, using muon and hadron beams. Main objectives for the spin program with the muon beam are the direct…
A new transversely polarised frozen spin target has been developed at MAMI which will be used in conjunction with the photon tagger and the Crystal Ball detector. The new target permits a major new programme of accurate measurement of…
The recent CLAS 2005, SAPHIR 2003, LEPS, and the old, pre-1972, data on K^+ Lambda photoproduction are compared with theoretical calculations in the energy region of E_gamma^lab < 2.6 GeV in order to learn about their mutual consistency.…
The CLAS collaboration has recently completed first measurements of the double polarization observables C_x and C_z for the reactions K^+Lambda and K^+Sigma^o photoproduction. C_x and C_z are the beam-recoil polarization asymmetries…
The construction of the ATLAS electromagnetic liquid argon calorimeter modules is completed and all the modules are assembled and inserted in the cryostats. During the production period four barrel and three endcap modules were exposed to…
The recently published experimental data on K+Lambda photoproduction by the SAPHIR, CLAS, and LEPS collaborations are analyzed by means of a multipole approach. For this purpose the background amplitudes are constructed from appropriate…
The large acceptance and high multiplicity capabilities of the CLAS detector make it possible to study a wide range of previously unmeasured strange baryon production processes. Studies of the decay angular distributions of electroproduced…
The recent results on $\gamma_vpN^*$ electrocouplings from analyses of the data on exclusive meson electroproduction off protons measured with the CLAS detector at Jefferson Lab are presented. The impact of these results on the exploration…
Exclusive photoproduction of $K^+ \Lambda$ final states off a proton target has been an important component in the search for missing nucleon resonances and our understanding of the production of final states containing strange quarks.…
New results on the single-differential and fully-integrated cross sections for the process $\gamma_{v} p \rightarrow p' \pi^{+} \pi^{-}$ are presented. The experimental data were collected with the CLAS detector at Jefferson Laboratory.…
We report measurements of target- and double-spin asymmetries for the exclusive channel $\vec e\vec p\to e\pi^+ (n)$ in the nucleon resonance region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). These asymmetries…