We report on a study of inclusive particle production in pp-interactions at 400 GeV/c. The data are based on 472 K reconstructed events recorded in the NA 27 experiment using the LEBC-EHS facility at CERN. The production cross sections are determined of pseudo scalar (π±,0, η andK±), scalar (f0(975)), vector (ρ±,0(770), ω(783), ϕ(1020),K*0(892), and\(\bar K^{ * 0} \)(892)), and tensorf0 mesons, of protons and antiprotons, and theΔ++,+,0(1232), and Λ(1520) baryon resonances in the forward hemisphere of the center of mass system, as well as longitudinal and transverse momentum distributions. The results are compared with predictions of the FRITIOF model and with other experimental data.
No description provided.
No description provided.
No description provided.
The ALICE Collaboration has measured inclusive J/psi production in pp collisions at a center of mass energy sqrt(s)=2.76 TeV at the LHC. The results presented in this Letter refer to the rapidity ranges |y|<0.9 and 2.5<y<4 and have been obtained by measuring the electron and muon pair decay channels, respectively. The integrated luminosities for the two channels are L^e_int=1.1 nb^-1 and L^mu_int=19.9 nb^-1, and the corresponding signal statistics are N_J/psi^e+e-=59 +/- 14 and N_J/psi^mu+mu-=1364 +/- 53. We present dsigma_J/psi/dy for the two rapidity regions under study and, for the forward-y range, d^2sigma_J/psi/dydp_t in the transverse momentum domain 0<p_t<8 GeV/c. The results are compared with previously published results at sqrt(s)=7 TeV and with theoretical calculations.
Double differential J/$\psi$ production cross section at $\sqrt{s}=2.76$ TeV. The first uncertainty is statistical, the second one is $p_{\rm T}$-coorelated, the third one is uncorrelated. Polarization-related uncertainties are not included.
The $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).
the $\sqrt{s}$-dependence of $\langle p_{\rm T}\rangle$ for inclusive J/$\psi$ production (forward rapidity).
We use 772$\times 10^6$ $B \bar{B}$ meson pairs collected at the $\Upsilon(4S)$ resonance with the Belle detector to measure the branching fraction for $\bar{B} \rightarrow X_s \gamma$. Our measurement uses a sum-of-exclusives approach in which 38 of the hadronic final states with strangeness equal to $+1$, denoted by $X_s$, are reconstructed. The inclusive branching fraction for $M_{X_s}<$ 2.8 GeV/$c^2$, which corresponds to a minimum photon energy of 1.9 GeV, is measured to be ${\cal B}(\bar{B} \rightarrow X_s \gamma)=(3.51\pm0.17\pm0.33)\times10^{-4}$, where the first uncertainty is statistical and the second is systematic.
The yields and partial branching fraction in each $M_{X_s}$ mass bin for the decay $\bar{B} \rightarrow X_s \gamma$, where $\bar{B}$ is either $\bar{B}^0$ or $B^-$, $X_s$ denotes all the hadron combinations that carry strangeness of +1, and charge conjugation is implied.
We present a measurement of angular observables, $P_4'$, $P_5'$, $P_6'$, $P_8'$, in the decay $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$, where $\ell^+\ell^-$ is either $e^+e^-$ or $\mu^+\mu^-$. The analysis is performed on a data sample corresponding to an integrated luminosity of $711~\mathrm{fb}^{-1}$ containing $772\times 10^{6}$ $B\bar B$ pairs, collected at the $\Upsilon(4S)$ resonance with the Belle detector at the asymmetric-energy $e^+e^-$ collider KEKB. Four angular observables, $P_{4,5,6,8}'$ are extracted in five bins of the invariant mass squared of the lepton system, $q^2$. We compare our results for $P_{4,5,6,8}'$ with Standard Model predictions including the $q^2$ region in which the LHCb collaboration reported the so-called $P_5'$ anomaly.
Results of the angular analysis of $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$ (where $\ell = e,\mu$) in five bins of $q^2$, the di-lepton invariant mass squared.
First measurements of the W -> lnu and Z/gamma* -> ll (l = e, mu) production cross sections in proton-proton collisions at sqrt(s) = 7 TeV are presented using data recorded by the ATLAS experiment at the LHC. The results are based on 2250 W -> lnu and 179 Z/gamma* -> ll candidate events selected from a data set corresponding to an integrated luminosity of approximately 320 nb-1. The measured total W and Z/gamma*-boson production cross sections times the respective leptonic branching ratios for the combined electron and muon channels are $\stotW$ * BR(W -> lnu) = 9.96 +- 0.23(stat) +- 0.50(syst) +- 1.10(lumi) nb and $\stotZg$ * BR(Z/gamma* -> ll) = 0.82 +- 0.06(stat) +- 0.05(syst) +- 0.09(lumi) nb (within the invariant mass window 66 < m_ll < 116 GeV). The W/Z cross-section ratio is measured to be 11.7 +- 0.9(stat) +- 0.4(syst). In addition, measurements of the W+ and W- production cross sections and of the lepton charge asymmetry are reported. Theoretical predictions based on NNLO QCD calculations are found to agree with the measurements.
Measured fiducial cross section times leptonic branching ratio for W+ production in the W+ -> e+ nu final state.
Measured fiducial cross section times leptonic branching ratio for W- production in the W- -> e- nubar final state.
Measured fiducial cross section times leptonic branching ratio for W+/- production in the combined W+ -> e+ nu and W- -> e- nubar final state.
The production of jets is studied in deep-inelastic ep scattering at large negative four momentum transfer squared 150<Q^2<15000 GeV^2 using HERA data taken in 1999-2007, corresponding to an integrated luminosity of 395 pb^-1. Inclusive jet, 2-jet and 3-jet cross sections, normalised to the neutral current deep-inelastic scattering cross sections, are measured as functions of Q^2, jet transverse momentum and proton momentum fraction. The measurements are well described by perturbative QCD calculations at next-to-leading order corrected for hadronisation effects. The strong coupling as determined from these measurements is alpha_s(M_Z) = 0.1168 +/-0.0007 (exp.) +0.0046/-0.0030 (th.) +/-0.0016(pdf).
Normalised inclusive jet cross section in bins of $Q^{2}$.
Normalised 2-jet cross section in bins of $Q^{2}$.
Normalised 3-jet cross section in bins of $Q^{2}$.
Theπ0 andη0 production is studied inπ−p interactions at 360 GeV/c. The cross section forπ0 production in the forward hemisphere (X>0) isσ(π0)=(49.7 ± 1.0 ± 1.1) mb and for η withX>0.1,Nch>2,σ(η0)=(3.1 ± 0.5) mb. The ratio of theπ0 toη0 cross section forX>0.1,Nch>2 isσ(π0)/σ(η0). Results on FeynmanX andpT distributions are presented. The data were obtained using the European Hybrid Spectrometer EHS and the bubble chamber LEBC at CERN.
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We report on a CDF measurement of the total cross section and rapidity distribution, $d\sigma/dy$, for $q\bar{q}\to \gamma^{*}/Z\to e^{+}e^{-}$ events in the $Z$ boson mass region ($66<M_{ee}<116$GeV/c$^2$) produced in $p\bar{p}$ collisions at $\sqrt{s}=1.96$TeV with 2.1fb$^{-1}$ of integrated luminosity. The measured cross section of $257\pm16$pb and $d\sigma/dy$ distribution are compared with Next-to-Leading-Order(NLO) and Next-to-Next-to-Leading-Order(NNLO) QCD theory predictions with CTEQ and MRST/MSTW parton distribution functions (PDFs). There is good agreement between the experimental total cross section and $d\sigma/dy$ measurements with theoretical calculations with the most recent NNLO PDFs.
Total cross section integrated up to ABS(YRAP)=2.9.
Rapiditiy distribution of E+ E- pairs in the mass range from 66 to 116 GeV.
The transverse momentum cross section of $e^+e^-$ pairs in the $Z$-boson mass region of 66-116 GeV/$c^2$ is precisely measured using Run II data corresponding to 2.1 fb$^{-1}$ of integrated luminosity recorded by the Collider Detector at Fermilab. The cross section is compared with quantum chromodynamic calculations. One is a fixed-order perturbative calculation at ${\cal O}(\alpha_s^2)$, and the other combines perturbative predictions at high transverse momentum with the gluon resummation formalism at low transverse momentum. Comparisons of the measurement with calculations show reasonable agreement. The measurement is of sufficient precision to allow refinements in the understanding of the transverse momentum distribution.
Total integrated cross section.
The differential PT cross section as a function of PT.
The product of the photoproduction cross section at 11.1 GeV for ψ(3105) on nucleons times the branching ratio for ψ into e+e− is less than 75 pb, at the 90% confidence level. This result implies a ψ-nucleon total cross section of less than 1.2 mb.
The branching ratio for J/PSI --> E+ E- is taken as 0.06.
The production of eta pi - system at low mass by the pi- beam in the Coulomb field of Be nuclei was studied. The cross section of the reaction pi- Be --> eta pi- Be was compared to the experimental data on the decay eta --> pi+ pi- gamma and to the theoretical predictions.
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The first measurements of the invariant differential cross sections of inclusive $\pi^0$ and $\eta$ meson production at mid-rapidity in proton-proton collisions at $\sqrt{s}=0.9$ TeV and $\sqrt{s}=7$ TeV are reported. The $\pi^0$ measurement covers the ranges $0.4<p_T<7$ GeV/$c$ and $0.3<p_T<25$ GeV/$c$ for these two energies, respectively. The production of $\eta$ mesons was measured at $\sqrt{s}=7$ TeV in the range $0.4<p_T<15$ GeV/$c$. Next-to-Leading Order perturbative QCD calculations, which are consistent with the $\pi^0$ spectrum at $\sqrt{s}=0.9$ TeV, overestimate those of $\pi^0$ and $\eta$ mesons at $\sqrt{s}=7$ TeV, but agree with the measured $\eta/\pi^0$ ratio at $\sqrt{s}=7$ TeV.
The measured invariant differential section for inclusive PI0 production at a centre-of-mass energy of 7 TeV.
The measured invariant differential section for inclusive PI0 production at a centre-of-mass energy of 0.9 TeV.
The measured invariant differential section for inclusive ETA production at a centre-of-mass energy of 7 TeV.
The PHENIX experiment has measured mid-rapidity transverse momentum spectra (0.4 < p_T < 5.0 GeV/c) of electrons as a function of centrality in Au+Au collisions at sqrt(s_NN)=200 GeV. Contributions from photon conversions and from light hadron decays, mainly Dalitz decays of pi^0 and eta mesons, were removed. The resulting non-photonic electron spectra are primarily due to the semi-leptonic decays of hadrons carrying heavy quarks. Nuclear modification factors were determined by comparison to non-photonic electrons in p+p collisions. A significant suppression of electrons at high p_T is observed in central Au+Au collisions, indicating substantial energy loss of heavy quarks.
Inclusive and non photonic electrons invariant yield versus PT, for minimum bias reactions.
Non photonic electrons invariant yield versus PT for different ranges of centrality.
Nuclear modification factor as a function of PT, for 0-10% central reactions Note that the systematic error given is related to the the uncertainties in the p+p measurements.An additional systematic error, symmetrical on the + and - side, related to the uncertainties in the Au+Au measurement, is given in the second column. Another, PT-independant, 13%systematic error due to the uncertainty on the overlap function and the Pi0 yield normalization is to add.
The PHENIX experiment has measured mid-rapidity transverse momentum spectra (0.4 < p_T < 4.0 GeV/c) of single electrons as a function of centrality in Au+Au collisions at sqrt(s_NN) = 200 GeV. Contributions to the raw spectra from photon conversions and Dalitz decays of light neutral mesons are measured by introducing a thin (1.7% X_0) converter into the PHENIX acceptance and are statistically removed. The subtracted ``non-photonic'' electron spectra are primarily due to the semi-leptonic decays of hadrons containing heavy quarks (charm and bottom). For all centralities, charm production is found to scale with the nuclear overlap function, T_AA. For minimum-bias collisions the charm cross section per binary collision is N_cc^bar/T_AA = 622 +/- 57 (stat.) +/- 160 (sys.) microbarns.
Value of the Alpha power as used in a fit of dN/dy versus Ncoll of the form A*Ncoll^Alpha, where N is the non photonic electron yield and Ncoll the number of p+p collisions This value only includes data from Au+Au collisions The value of Alpha = 1 is the expectation in the absence of medium effects.
Value of the Alpha power as used in a fit of dN/dy versus Ncoll, of the form A*Ncoll^Alpha, where N is the non photonic electron yield and Ncoll the number of p+p collisions This value is calculated including previous data of p+p collisions, measured by PHENIX, in addition of the Au+Au data The value of Alpha = 1 is the expectation in the absence of medium effects.
Spectrum in transverse momentum of electrons created in open heavy flavor decays, for minimum bias events.
J/psi production has been measured in proton-proton collisions at sqrt(s)= 200 GeV over a wide rapidity and transverse momentum range by the PHENIX experiment at RHIC. Distributions of the rapidity and transverse momentum, along with measurements of the mean transverse momentum and total production cross section are presented and compared to available theoretical calculations. The total J/psi cross section is 3.99 +/- 0.61(stat) +/- 0.58(sys) +/- 0.40(abs) micro barns. The mean transverse momentum is 1.80 +/- 0.23(stat) +/- 0.16(sys) GeV/c.
Measured J/PSI distribution in PT for the e+e- channel. The value of B, the branching fraction to either electrons or muons is the average value from PDG : 5.9%.The rapidity range is -0.35<y<0.35. Incertainties are 1-sigma statistical errors on the (signal - background) net yield. There is a 10% overall absolute cross section normalization error in addition to the error given.
Measured J/PSI distribution in PT for the mu+mu- channel. The value of B, the branching fraction to either electrons or muons, is the average value from PDG: 5.9%.The rapidity range is -2.2<y<-1.2. Incertainties are 1-sigma statistical errors on the (signal - background) net yield.There is a 10% overall absolute cross section normalization error in addition to the error given.
J/PSI distribution in rapidity. The data at rapidity = 0 is from the electron arm, the data from the muon arm, corresponding to forward rapidity is divided in two bins.The value of B,the branching fraction to either electrons or muons, is 5.9%, the average value from PDG.Incertainties are 1-sigma statistical errors on the (signal - background) net yield.There is a 10% overall absolute cross section normalization error in addition to the error given.
First results on charm quarkonia production in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The yield of J/Psi's measured in the PHENIX experiment via electron-positron decay pairs at mid-rapidity for Au-Au reactions at sqrt(s_NN) = 200 GeV are analyzed as a function of collision centrality. For this analysis we have studied 49.3 million minimum bias Au-Au reactions. We present the J/Psi invariant yield dN/dy for peripheral and mid-central reactions. For the most central collisions where we observe no signal above background, we quote 90% confidence level upper limits. We compare these results with our J/Psi measurement from proton-proton reactions at the same energy. We find that our measurements are not consistent with models that predict strong enhancement relative to binary collision scaling.
Measured invariant differential yield at mid-rapidity of J/PSI, as a function of centratility, times branching ratio Be+e-, for three bins of centrality : 0-20%, 20-40% and 40-90% of Au-Au cross-section. The 90% confidence level upper limit (CLUL) for the yield is also given.
Measured differential yield of J/PSI per binary collisions,at mid rapidity, as a function of the centrality, times branching ratio Be+e-.The 90% confidence level upper limit (CLUL) for J/PSI differential yield is also given. The values of the number of participants for each centrality bins are calculated for general information.
We report the first measurement of the differential cross section for the process gamma gamma --> eta eta in the kinematic range above the eta eta threshold, 1.096 GeV < W < 3.8 GeV over nearly the entire solid angle range, |cos theta*| <= 0.9 or <= 1.0 depending on W, where W and theta* are the energy and eta scattering angle, respectively, in the gamma gamma center-of-mass system. The results are based on a 393 fb^{-1} data sample collected with the Belle detector at the KEKB e^+ e^- collider. In the W range 1.1-2.0 GeV/c^2 we perform an analysis of resonance amplitudes for various partial waves, and at higher energy we compare the energy and the angular dependences of the cross section with predictions of theoretical models and extract contributions of the chi_{cJ} charmonia.
Total cross section.
Angular dependence of the differential cross section for the W range 1.096 to 1.120 GeV.
Angular dependence of the differential cross section for the W range 1.120 to 1.160 GeV.
The production of $\phi$ mesons in the reaction $e~{+}p \rightarrow e~{+} \phi p$ ($\phi \rightarrow K~{+}K~{-}$) at a median $Q~{2}$ of $10~{-4} \ \rm{GeV~2}$ has been studied with the ZEUS detector at HERA. The differential $\phi$ photoproduction cross section $d\sigma/dt$ has an exponential shape and has been determined in the kinematic range $0.1<|t|<0.5 \ \rm{GeV~2}$ and $60 < W < 80 \ \rm{GeV}$. An integrated cross section of $\sigma_{\gamma p \rightarrow \phi p} = 0.96 \pm 0.19~{+0.21}_{-0.18}$ $\rm{\mu b}$ has been obtained by extrapolating to {\it t} = 0. When compared to lower energy data, the results show a weak energy dependence of both $\sigma_{\gamma p \rightarrow \phi p}$ and the slope of the $t$ distribution. The $\phi$ decay angular distributions are consistent with $s$-channel helicity conservation. From lower energies to HERA energies, the features of $\phi$ photoproduction are compatible with those of a soft diffractive process.
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Numerical values of dsig/dt distribution requested from authors.
Numerical values of dsig/dt distribution read from plot.
Measurements of the proton and deuteron $F_2$ structure functions are presented. The data, taken at Jefferson Lab Hall C, span the four-momentum transfer range $0.06 < Q^2 < 2.8$ GeV$^2$, and Bjorken $x$ values from 0.009 to 0.45, thus extending the knowledge of $F_2$ to low values of $Q^2$ at low $x$. Next-to-next-to-leading order calculations using recent parton distribution functions start to deviate from the data for $Q^2<2$ GeV$^2$ at the low and high $x$-values. Down to the lowest value of $Q^2$, the structure function is in good agreement with a parameterization of $F_2$ based on data that have been taken at much higher values of $Q^2$ or much lower values of $x$, and which is constrained by data at the photon point. The ratio of the deuteron and proton structure functions at low $x$ remains well described by a logarithmic dependence on $Q^2$ at low $Q^2$.
Proton and Deuteron F2 structure function for an x value of 0.040, determined via the Rosenbluth separation method. Error is shown without the contribution from radiative corrections.
Proton and Deuteron F2 structure function for an x value of 0.060, determined via the Rosenbluth separation method. Error is shown without the contribution from radiative corrections.
Proton and Deuteron F2 structure function for an x value of 0.080, determined via the Rosenbluth separation method. Error is shown without the contribution from radiative corrections.
We report on the measurement of inclusive electron scattering off a carbon target performed with CLAS at Jefferson Laboratory. A combination of three different beam energies 1.161, 2.261 and 4.461 GeV allowed us to reach an invariant mass of the final-state hadronic system W~2.4 GeV with four-momentum transfers Q2 ranging from 0.2 to 5 GeV2. These data, together with previous measurements of the inclusive electron scattering off proton and deuteron, which cover a similar continuous two-dimensional region of Q2 and Bjorken variable x, permit the study of nuclear modifications of the nucleon structure. By using these, as well as other world data, we evaluated the F2 structure function and its moments. Using an OPE-based twist expansion, we studied the Q2-evolution of the moments, obtaining a separation of the leading-twist and the total higher-twist terms. The carbon-to-deuteron ratio of the leading-twist contributions to the F2 moments exhibits the well known EMC effect, compatible with that discovered previously in x-space. The total higher-twist term in the carbon nucleus appears, although with large systematic uncertainites, to be smaller with respect to the deuteron case for n<7, suggesting partial parton deconfinement in nuclear matter. We speculate that the spatial extension of the nucleon is changed when it is immersed in the nuclear medium.
F2 measurements for a Q**2 of 0.175 GeV**2.
F2 measurements for a Q**2 of 0.225 GeV**2.
F2 measurements for a Q**2 of 0.275 GeV**2.
Diffractive electroproduction of rho and phi mesons is measured at HERA with the H1 detector in the elastic and proton dissociative channels. The data correspond to an integrated luminosity of 51 pb^-1. About 10500 rho and 2000 phi events are analysed in the kinematic range of squared photon virtuality 2.5 < Q^2 < 60 GeV^2, photon-proton centre of mass energy 35 < W < 180 GeV and squared four-momentum transfer to the proton |t| < 3 GeV^2. The total, longitudinal and transverse cross sections are measured as a function of Q^2, W and |t|. The measurements show a transition to a dominantly "hard" behaviour, typical of high gluon densities and small q\bar{q} dipoles, for Q^2 larger than 10 to 20 GeV^2. They support flavour independence of the diffractive exchange, expressed in terms of the scaling variable (Q^2 + M_V^2)/4, and proton vertex factorisation. The spin density matrix elements are measured as a function of kinematic variables. The ratio of the longitudinal to transverse cross sections, the ratio of the helicity amplitudes and their relative phases are extracted. Several of these measurements have not been performed before and bring new information on the dynamics of diffraction in a QCD framework. The measurements are discussed in the context of models using generalised parton distributions or universal dipole cross sections.
Q**2 dependence of the GAMMA* P elastic RHO0 meson production at mean W There is an additional overall normalization uncertainty of 3.9 PCT.
Q**2 dependence of the GAMMA* P cross section for proton dissociative RHO0 meson production at mean W There is an additional overall normalization uncertainty of 4.6 PCT.
Q**2 dependence of the GAMMA* P elastic PHI meson production at mean W There is an additional overall normalization uncertainty of 4.7 PCT.
A measurement of elastic deeply virtual Compton scattering gamma* p -> gamma p using e^+ p and e^- p collision data recorded with the H1 detector at HERA is presented. The analysed data sample corresponds to an integrated luminosity of 306 pb^-1, almost equally shared between both beam charges. The cross section is measured as a function of the virtuality Q^2 of the exchanged photon and the centre-of-mass energy W of the gamma* p system in the kinematic domain 6.5 < Q^2 < 80 GeV^2, 30 < W < 140 GeV and |t| < 1 GeV^2, where t denotes the squared momentum transfer at the proton vertex. The cross section is determined differentially in t for different Q^2 and W values and exponential t-slope parameters are derived. Using e^+ p and e^- p data samples, a beam charge asymmetry is extracted for the first time in the low Bjorken x kinematic domain. The observed asymmetry is attributed to the interference between Bethe-Heitler and deeply virtual Compton scattering processes. Experimental results are discussed in the context of two different models, one based on generalised parton distributions and one based on the dipole approach.
The DVCS cross section as a function of Q**2.
The DVCS cross section as a function of W.
The DVCS cross section as a function of W for three different Q**2 regions.
A measurement of the inclusive deep-inelastic neutral current e+p scattering cross section is reported in the region of four-momentum transfer squared, 12<=Q^2<=150 GeV^2, and Bjorken x, 2x10^-4<=x<=0.1. The results are based on data collected by the H1 Collaboration at the ep collider HERA at positron and proton beam energies of E_e=27.6 GeV and E_p=920 GeV, respectively. The data are combined with previously published data, taken at E_p=820 GeV. The accuracy of the combined measurement is typically in the range of 1.3-2%. A QCD analysis at next-to-leading order is performed to determine the parton distributions in the proton based on H1 data.
Data from the 2000 running period at Q**2 There is an additional 1.2 PCT overall normalisation uncertainty not included.
Data from the 2000 running period at Q**2 There is an additional 1.2 PCT overall normalisation uncertainty not included.
Data from the 2000 running period at Q**2 There is an additional 1.2 PCT overall normalisation uncertainty not included.
Events with high energy isolated electrons, muons or tau leptons and missing transverse momentum are studied using the full e^\pm p data sample collected by the H1 experiment at HERA, corresponding to an integrated luminosity of 474 pb^{-1}. Within the Standard Model, events with isolated leptons and missing transverse momentum mainly originate from the production of single W bosons. The total single W boson production cross section is measured as 1.14 \pm 0.25 (stat.) \pm 0.14 (sys.) pb, in agreement with the Standard Model expectation. The data are also used to establish limits on the WW\gamma gauge couplings and for a measurement of the W boson polarisation.
Total single W boson production cross section.
Differential single W boson production cross section.
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
Differential cross sections at Q**2=6.564 GeV**2, EPSILON=0.4523, W=1.112 GeV and COS(THETA(*))=-0.9 for the small SOS spectrometer.
Differential cross sections at Q**2=6.564 GeV**2, EPSILON=0.4523, W=1.112 GeV and COS(THETA(*))=-0.7 for the small SOS spectrometer.
Differential cross sections at Q**2=6.564 GeV**2, EPSILON=0.4523, W=1.112 GeV and COS(THETA(*))=-0.5 for the small SOS spectrometer.
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