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'1'. '2'. 'GLAUB'.
The dimuon production in 200 GeV/nucleon O-U, O-Cu, S-U and p-U reactions is studied in function of transverse energy E T produced by the collision. The J / ψ production relative to continuum events is suppressed for heavy ion induced reactions when E T increases. This suppression is enhanced at low transverse momentum. The π and K meson distributions extracted from the data, have, for each reaction, a similar average transverse momentum which increases only slightly with the transverse energy.
No description provided.
No description provided.
No description provided.
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'1'. '2'. '3'.
No description provided.
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Differential cross section and polarization distributions are presented for elastic p p scattering at incident momenta of 1.73, 2.13, 2.37 and 2.97 GeV/ c . The data have been analysed in terms of a 5-parameter diffraction model. In terms of this model the difference in the shape of the differential cross sections for p p and pp elastic scattering is a result of the strong absorption in the p p system.
'1'. '2'. '3'. '4'.
'3'.
'2'.
We study the lepton forward-backward asymmetry AFB and the longitudinal K* polarization FL, as well as an observable P2 derived from them, in the rare decays B->K*l+l-, where l+l- is either e+e- or mu+mu-, using the full sample of 471 million BBbar events collected at the Upsilon(4S) resonance with the Babar detector at the PEP-II e+e- collider. We separately fit and report results for the B+->K*+l+l- and B0->K*0l+l- final states, as well as their combination B->K*l+l-, in five disjoint dilepton mass-squared bins. An angular analysis of B+->K*+l+l- decays is presented here for the first time.
$F_L$ angular fit results.
$A_{FB}$ angular fit results.
$P_2$ results with total uncertainties.
In an analysis of a 2.92~fb$^{-1}$ data sample taken at 3.773~GeV with the BESIII detector operated at the BEPCII collider, we measure the absolute decay branching fractions to be $\mathcal B(D^0 \to K^-e^+\nu_e)=(3.505\pm 0.014 \pm 0.033)\%$ and $\mathcal B(D^0 \to \pi^-e^+\nu_e)=(0.295\pm 0.004\pm 0.003)\%$. From a study of the differential decay rates we obtain the products of hadronic form factor and the magnitude of the CKM matrix element $f_{+}^K(0)|V_{cs}|=0.7172\pm0.0025\pm 0.0035$ and $f_{+}^{\pi}(0)|V_{cd}|=0.1435\pm0.0018\pm 0.0009$. Combining these products with the values of $|V_{cs(d)}|$ from the SM constraint fit, we extract the hadronic form factors $f^K_+(0) = 0.7368\pm0.0026\pm 0.0036$ and $f^\pi_+(0) = 0.6372\pm0.0080\pm 0.0044$, and their ratio $f_+^{\pi}(0)/f_+^{K}(0)=0.8649\pm 0.0112\pm 0.0073$. These form factors and their ratio are used to test unquenched Lattice QCD calculations of the form factors and a light cone sum rule (LCSR) calculation of their ratio. The measured value of $f_+^{K(\pi)}(0) |V_{cs(d)}|$ and the lattice QCD value for $f^{K(\pi)}_+(0)$ are used to extract values of the CKM matrix elements of $|V_{cs}|=0.9601 \pm 0.0033 \pm 0.0047 \pm 0.0239$ and $|V_{cd}|=0.2155 \pm 0.0027 \pm 0.0014 \pm 0.0094$, where the third errors are due to the uncertainties in lattice QCD calculations of the form factors. Using the LCSR value for $f_+^\pi(0)/f_+^K(0)$, we determine the ratio $|V_{cd}|/|V_{cs}|=0.238\pm 0.004\pm 0.002\pm 0.011$, where the third error is from the uncertainty in the LCSR normalization. In addition, we measure form factor parameters for three different theoretical models that describe the weak hadronic charged currents for these two semileptonic decays. All of these measurements are the most precise to date.
Summary of the range of each $q^2$ bin, the number of the observed events $N_{\rm observed}$, the number of produced events $N_{\rm produced}$, and the partial decay rate $\Delta\Gamma$ in each $q^2$ bin for $D^0\to K^-e^+\nu_e$ decays.
Summary of the range of each $q^2$ bin, the number of the observed events $N_{\rm observed}$, the number of produced events $N_{\rm produced}$, and the partial decay rate $\Delta\Gamma$ in each $q^2$ bin for $D^0\to \pi^-e^+\nu_e$ decays.
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No description provided.
Axis error includes +- 0.0/0.0 contribution.
No description provided.
Angular, multiplicity and velocity distributions as well as azimuthai asymmetries of light fragments (Z = 1 and 2) correlated with large transverse momentum protons detected at 90° have been measured in 16O + 27Al collisions at 94 MeV/u. Data are compared with a model based on the standard high-energy fireball geometry coupled with the Weisskopf theory of evaporation. Reasonable agreement is achieved with the exception of some discrepancies which could arise either from the absence of specific intermediate-energy corrections or from a non-statistical process.
No description provided.
No description provided.
The ratio R = σ (e + + p)/ σ (e − + p) of the elastic scattering cross-section detecting the recoil proton at 0 o in coincidence with the backward electron or positron was found to be R = 1.036 ± 0.018 at q 2 = 8 fm −2 , R = 1.079 ± 0.046 at q 2 = 32 fm −2 .
Axis error includes +- 0.0/0.0 contribution (?////Errors presented are the total combined statistical and systematic error s. Radiative corrections applied).
Axis error includes +- 0.0/0.0 contribution (?////Errors presented are the total combined statistical and systematic error s. Radiative corrections applied).
At the projectile-fragment separator FRS of GSI, relativistic secondary beams of about 520 MeV/nucleon were produced by fragmentation of a primary beam of58Ni at 650 MeV/nucleon in a beryllium target. By means of aΔE—Bρ—TOF measurement, the fragments have been identified and their charge-changing probabilities in targets of CH2, C, Al, and Pb have been determined. We describe the results for the total charge-changing cross sections in this first paper, whereas a second article deals with the partial charge-changing cross sections. At the drip line, the measured charge-changing cross sections exhaust close to 100% of the total interaction cross sections as calculated with semiempirical models. The measurements at the proton drip line with low-Z targets indicate that only a very small increase of the cross sections may be observed, whereas the measurements with a lead target show that no significant increase of the total charge-changing cross sections is present which would be a hint for low-lying dipole strength. Our experimental data are compared to Glauber-type calculations.
Nucleus is C H2.
Nucleus is C H2.
Nucleus is C H2.
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