A measurement of the total $pp$ cross section at the LHC at $\sqrt{s}=8$ TeV is presented. An integrated luminosity of $500$ $\mu$b$^{-1}$ was accumulated in a special run with high-$\beta^{\star}$ beam optics to measure the differential elastic cross section as a function of the Mandelstam momentum transfer variable $t$. The measurement is performed with the ALFA sub-detector of ATLAS. Using a fit to the differential elastic cross section in the $-t$ range from $0.014$ GeV$^2$ to $0.1$ GeV$^2$ to extrapolate $t\rightarrow 0$, the total cross section, $\sigma_{\mathrm{tot}}(pp\rightarrow X)$, is measured via the optical theorem to be: $\sigma_{\mathrm{tot}}(pp\rightarrow X) = {96.07} \; \pm 0.18 \; ({{stat.}}) \pm 0.85 \; ({{exp.}}) \pm 0.31 \; ({extr.}) \; {mb} \;,$ where the first error is statistical, the second accounts for all experimental systematic uncertainties and the last is related to uncertainties in the extrapolation $t\rightarrow 0$. In addition, the slope of the exponential function describing the elastic cross section at small $t$ is determined to be $B = 19.74 \pm 0.05 \; ({{stat.}}) \pm 0.23 \; ({{syst.}}) \; {GeV}^{-2}$.
The measured total cross section, the first systematic error accounts for all experimental uncertainties and the second error for the extrapolation t-->0.
The nuclear slope of the differential eslastic cross section at small |t|, the first systematic error accounts for all experimental uncertainties and the second error for the extrapolation t-->0.
The total elastic cross section and the observed elastic cross section within the fiducial volume.
A measurement of the total $pp$ cross section at the LHC at $\sqrt{s}=7$ TeV is presented. In a special run with high-$\beta^{\star}$ beam optics, an integrated luminosity of 80 $\mu$b$^{-1}$ was accumulated in order to measure the differential elastic cross section as a function of the Mandelstam momentum transfer variable $t$. The measurement is performed with the ALFA sub-detector of ATLAS. Using a fit to the differential elastic cross section in the $|t|$ range from 0.01 GeV$^2$ to 0.1 GeV$^2$ to extrapolate to $|t|\rightarrow 0$, the total cross section, $\sigma_{\mathrm{tot}}(pp\rightarrow X)$, is measured via the optical theorem to be: $$\sigma_{\mathrm{tot}}(pp\rightarrow X) = 95.35 \; \pm 0.38 \; ({\mbox{stat.}}) \pm 1.25 \; ({\mbox{exp.}}) \pm 0.37 \; (\mbox{extr.}) \; \mbox{mb},$$ where the first error is statistical, the second accounts for all experimental systematic uncertainties and the last is related to uncertainties in the extrapolation to $|t|\rightarrow 0$. In addition, the slope of the elastic cross section at small $|t|$ is determined to be $B = 19.73 \pm 0.14 \; ({\mbox{stat.}}) \pm 0.26 \; ({\mbox{syst.}}) \; \mbox{GeV}^{-2}$.
The measured total cross section, the first systematic error accounts for all experimental uncertainties and the second error for the extrapolation t-->0.
The nuclear slope of the differential eslastic cross section at small |t|, the first systematic error accounts for all experimental uncertainties and the second error for the extrapolation t-->0.
The Optical Point dsigma/(elastic)/dt(t-->0), the total elastic cross section and the observed elastic cross section within the fiducial volume. The first systematic error accounts for all experimental uncertainties and the second error for the extrapolation t-->0.
Results are presented onK+p elastic scattering and on the reactionK+p→K+pπ+π− at 70 GeV/c. For the
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INTEGRATION OVER RANGE OF ABS(T) FROM 0 TO 1 GEV.
Differential cross sections of p p forward elastic scattering were measured between 400 and 730 MeV/ c , and the real-to-imaginary ratio, ϱ, of the forward amplitude was deduced. We found that ρ increases from ∼ 0.1 to ∼ 0.4 in this momentum range. A dispersion-relation analysis shows the existence of a pole-like structure in the real part of the p p amplitude near threshold.
REAL/IMAG RATIO OF FORWARD AMPLITUDE DETERMINED FROM FIT TO COULOMB-NUCLEARINTERFERENCE.
The differential cross-sections for the elastic scattering of protons on deuterium have been measured at 600 MeV in the |t| range between 0.003 and 0.030 (GeV/c)2. The results are analysed by using the Bethe and Glauber formalisms taking into account spin effects in deuterium wave function and nucleon-nucleon amplitudes. The ratio between the real and the imaginary parts of the spin-independent protonneutron amplitude αpn deduced from dispersion calculations and phase shift analysis is compared with experimental results.
No description provided.
The polarization parameter in pn elastic scattering has been measured at 24 GeV/ c over the range of four-momentum transfer squared 0.1 < | t | < 1.25 (GeV/ c ) 2 , and found to be negative except for a zero at | t | = 0.65 (GeV/ c ) 2 .
No description provided.
The polarization of scattered antiproton in\(\bar pp\) elastic scattering has been measured at the kinetic energy of 220MeV by means of double scattering in a bubble chamber. The polarizations obtained are 0.28±0.11, 0.46±0.12, 0.51±0.19 and 0.38±0.31 at the scattering angles 28°, 42°, 56° and 73° in the c.m. system, respectively. These results do not seem to be in good agreement with a prediction given by Bryan and Phillips. We have also compared these data with a modified diffraction model.
POLARIZATION ASSUMED POSITIVE.
The polarization for the\(\bar pp\) elastic scattering was measured as a function of the centre-of-mass angle of scattering between 17° and 90° at the average incident momentum of 0.7 GeV/c by using doublescattering events in a bubble chamber. The average value of the polarization was found to be 0.23 ± 0.05. The angular dependence of the polarization obtained in this experiment was interpreted by the strong absorptive potential model for\(\bar {\mathcal{N}}{\mathcal{N}}\) interactions recently proposed.
SIGN OF POLARIZATION TAKEN AS POSITIVE ACCORDING TO THE DATA OF ALBROW ET AL., NP B37, 349 (1972).
The polarization parameters of the pn elastic scattering were measured at beam momenta between 1.30 and 1.82 GeV/c. The results are discussed in comparison with the partial-wave analysis of Hashimoto and Hoshizaki.
ERRORS ARE STATISTICAL ONLY.
ERRORS ARE STATISTICAL ONLY.
ERRORS ARE STATISTICAL ONLY.
We have measured the analyzing power A y in n-d elastic scattering at 67.0 MeV. The experiment was based on the detection of recoil deuterons, allowing for a precise measurement of the backward angular range. The results are in good agreement with recent three-nucleon calculations which are based on the Paris and Bonn NN potentials.
No description provided.
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