Download or read book Neutral Pion Electroproduction in the Resonance Region at High Q 2 written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The process $ep \to e^{\prime}p^{\prime}\pi^0$ has been measured at $Q^2$ = 6.4 and 7.7 \ufourmomts in Jefferson Lab's Hall C. Unpolarized differential cross sections are reported in the virtual photon-proton center of mass frame considering the process $\gamma^{\ast}p \to p^{\prime}\pi^0$. Various details relating to the background subtractions, radiative corrections and systematic errors are discussed. The usefulness of the data with regard to the measurement of the electromagnetic properties of the well known $\Delta(1232)$ resonance is covered in detail. Specifically considered are the electromagnetic and scalar-magnetic ratios $R_{EM}$ and $R_{SM}$ along with the magnetic transition form factor $G_M^{\ast}$. It is found that the rapid fall off of the $\Delta(1232)$ contribution continues into this region of momentum transfer and that other resonances.
Download or read book Neutral Pion Electroproduction in the Resonance Region written by and published by . This book was released on 2007 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: The electroproduction of baryon resonances at high Q2 is examined. Analysis focuses on the ?(1232) resonance via exclusive pseudoscalar meson production of ?0 particles. Differential cross sections are extracted for exclusive ?0 electroproduction. In the central invariant mass (W) region the cross sections are used to extract resonant multipole amplitudes. In particular, the ratio of the electric quadrupole to magnetic dipole amplitudes (E2/M1) will be discussed for the ?(1232) resonance. The transition to pQCD is discussed in terms of E2/M1 and other multipoles. The helicity amplitude A3/2 can be used as a baryon helicity conservation meter in this context and will be discussed. The fast shrinking of the resonant contribution in the ? region is observed at this high momentum transfer. Apart from the observables related to pQCD scaling, the transition form factor G$*\atop{M}$ is extracted along with the scalar to magnetic dipole ratio C2/M1.
Download or read book Neutral Pion Electroproduction in the Delta Resonance Region written by Anthony Nicholas Villano and published by ProQuest. This book was released on 2007 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Neutral Pion Electroproduction in the Delta Resonance Region written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The electroproduction of baryon resonances at high Q2 is examined. Analysis focuses on the Delta(1232) resonance via exclusive pseudoscalar meson production of À0 particles. Differential cross sections are extracted for exclusive À0 electroproduction. In the central invariant mass (W) region the cross sections are used to extract resonant multipole amplitudes. In particular, the ratio of the electric quadrupole to magnetic dipole amplitudes (E2/M1) will be discussed for the Delta(1232) resonance. The transition to pQCD is discussed in terms of E2/M1 and other multipoles. The helicity amplitude A3/2 can be used as a baryon helicity conservation meter in this context and will be discussed. The fast shrinking of the resonant contribution in the Delta region is observed at this high momentum transfer. Apart from the observables related to pQCD scaling, the transition form factor GM is extracted along with the scalar to magnetic dipole ratio C2/M1.
Download or read book Songes d un hermite written by and published by . This book was released on 1788 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pion Electroproduction in the Second Resonance Region Using CLAS written by Inna Aznauryan and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The differential cross sections and the single beam asymmetries have been measured for the single pion electroproduction on the proton at Q2 = 0.4 GeVZ using CLAS. The large phase space coverage of CLAS and the high statistical accuracy of the data allowed us to perform the analysis of single pion electroproduction observables and to obtain the A1/2 amplitudes for the S11(1535). The preliminary results of this analysis are in good agreement with the {eta}-meson production data.
Download or read book Virtual Compton Scattering and Neutral Pion Electro production from the Proton in the Nucleon Resonance Region written by Luminita Todor and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The experiment (E93-050) at Jefferson Lab measured the ep {yields} ep{gamma} and ep {yields} ep{pi}{sup 0} cross sections in the nucleon resonance region, from the threshold to W = 1.9 GeV at Q{sup 2} = 1 GeV{sup 2} for backward emission of the {gamma} or {pi}{sup 0}.
Download or read book Recoil Polarization Measurements for Neutral Pion Electroproduction at Q 2 written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We measured angular distributions of differential cross section, beam analyzing power, and recoil polarization for neutral pion electroproduction at Q2 = 1.0 (GeV/c)2 in 10 bins of W across the Delta resonance. A total of 16 independent response functions were extracted, of which 12 were observed for the first time. Comparisons with recent model calculations show that response functions governed by real parts of interference products are determined relatively well near 1.232 GeV, but variations among models is large for response functions governed by imaginary parts and for both increases rapidly with W. We performed a nearly model-independent multipole analysis that adjusts complex multipoles with high partial waves constrained by baseline models. Parabolic fits to the W dependence of the multipole analysis around the Delta mass gives values for SMR = ( -6.61 +/- 0.18)% and EMR = ( -2.87 +/- 0.19)% that are distinctly larger than those from Legendre analysis of the same data. Similarly, the multipole analysis gives Re(S0+/M1+) = (+7.1 +/- 0.8)% at W=1.232 GeV, consistent with recent models, while the traditional Legendre analysis gives the opposite sign because its truncation errors are quite severe. Finally, using a unitary isobar model (UIM), we find that excitation of the Roper resonance is dominantly longitudinal with S1/2 = (0.05 +/- 0.01) GeV{sup ( -1/2)} at Q2=1. The ReS0+ and ReE0+ multipoles favor pseudovector coupling over pseudoscalar coupling or a recently proposed mixed-coupling scheme, but the UIM does not reproduce the imaginary parts of 0+ multipoles well.
Download or read book Virtual Compton Scattering and Neutral Pion Electro production from the Proton in the Nucleon Resonance Region written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The experiment (E93-050) at Jefferson Lab measured the ep [yields] ep[gamma] and ep [yields] ep[pi][sup 0] cross sections in the nucleon resonance region, from the threshold to W = 1.9 GeV at Q[sup 2] = 1 GeV[sup 2] for backward emission of the [gamma] or [pi][sup 0].
Download or read book Electroproduction of Neutral Pions in the Resonance Region written by and published by . This book was released on 1975 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Exclusive Neutral Pion Electroproduction in the Deeply Virtual Regime written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present measurements of the ep->ep pi^0 cross section extracted at two values of four-momentum transfer Q^2=1.9 GeV^2 and Q^2=2.3 GeV^2 at Jefferson Lab Hall A. The kinematic range allows to study the evolution of the extracted hadronic tensor as a function of Q^2 and W. Results will be confronted with Regge inspired calculations and GPD predictions. An intepretation of our data within the framework of semi-inclusive deep inelastic scattering has also been attempted.
Download or read book Pion Electroproduction from the Deuteron in the Delta 1230 Resonance Region written by Satyavrat Mehrotra and published by . This book was released on 1981 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electroproduction of Neutral Pions at Energies Above the Resonance Region written by and published by . This book was released on 1975 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pion Electroproduction in the Triangle sup 3 3 Resonance Region written by Serdar Nergiz and published by . This book was released on 1985 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Single Pion Electroproduction in Delta 1232 and Roper Resonance Region with CLAS written by Kyungseon Joo and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Single pion electroproduction in the resonance region has been studied as a means of exploring the physics underlying the structure of the nucleon. Recent experiments using CLAS at Jefferson Lab/Hall B have measured unpolarized cross sections and beam spin asymmetries over a large kinematic range. The high statistical accuracy of this data set provides important information on the Delta(1232) and the Roper.
Download or read book Unitary Constraints on Neutral Pion Electroproduction written by and published by . This book was released on 2010 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: At large virtuality $Q^2$, the coupling to the vector meson production channels provides us with a natural explanation of the surprisingly large cross section of the neutral pion electroproduction recently measured at Jefferson Laboratory, without destroying the good agreement between the Regge pole model and the data at the real photon point. Lastly, elastic rescattering of the $\pi^0$ provides us with a way to explain why the node, that appears at $t\sim -0.5$~GeV$^2$ at the real photon point, disappears as soon as $Q^2$ differs from zero.
Download or read book Electroproduction of Pions Beyond the Resonance Region and the Pion Form Factor written by W. Schmidt and published by . This book was released on 1971 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
