31 research outputs found
Das Higgs-Teilchen und der Rest der Welt : Langjährige Suche ist endlich von Erfolg gekrönt
No full textPhysiker am CERN in Genf haben in diesem Sommer die Beobachtung eines neuen Teilchens bekannt gegeben. Dabei handelt es sich um das schwerste je beobachtete elementare Teilchen, das 134mal so schwer wie das Proton ist. Vieles spricht dafür, dass es sich bei der Beobachtung um das lange gesuchte Higgs-Teilchen handelt, den letzten fehlenden Baustein im Standardmodell der Teilchenphysik. Die Arbeitsgruppe von Prof. Düren und Dr. Stenzel am II. Physikalischen Institut der Justus-Liebig-Universität ist als Mitglied der ATLAS-Kollaboration an den Messungen beteiligt
Studies of QCD at LEPII
No full textA combination of measurements of alpha_s in e+e- annihilation at LEP is presented. Distributions of various event-shape variables measured by ALEPH, DELPHI, L3 and OPAL at centre-of-mass energies from 41 GeV to 206 GeV are analysed in a common theoretical framework using O(a_s**2)+NLLA predictions. The dominant theoretical uncertainties associated to missing higher orders are studied in detail.A combination of measurements of alpha_s in e+e- annihilation at LEP is presented. Distributions of various event-shape variables measured by ALEPH, DELPHI, L3 and OPAL at centre-of-mass energies from 41 GeV to 206 GeV are analysed in a common theoretical framework using O(a_s**2)+NLLA predictions. The dominant theoretical uncertainties associated to missing higher orders are studied in detail
Total cross section and elastic scattering from TEVATRON to LHC
No full textA review of elastic scattering and total cross section measurements using the luminosity-independent method at the TEVATRON and prospect for the LHC. Conference talk at PHOTON09
Measurement of the total cross section from elastic scattering in pp collisions at s=7 TeV with the ATLAS detector
No full textAbstractIn this contribution a measurement of the total pp cross section with the ATLAS detector at the LHC at s=7 TeV is presented. In a special run with high-β⋆ beam optics, the differential elastic cross section is measured 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 GeV2 to 0.1 GeV2 to extrapolate to |t|→0, the total cross section, σtot(pp→X), is measured via the optical theorem to be:σtot(pp→X)=95.35±0.38(stat.)±1.25(exp.)±0.37(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 to |t|→0. In addition, the slope of the elastic cross section at small |t| is determined to be B = 19.73 ± 0.14 (stat.) ± 0.26 (syst.) GeV-2
Measurement of the total cross section at 8 TeV and the inelastic cross section at 13 TeV at the LHC with the ATLAS detector
No full textNew measurements from ATLAS at the LHC are presented on the total cross section at TeV from elastic scattering using the ALFA sub-detector and on the inelastic cross section at TeV using the MBTS sub-detector
Measurements of the total and inelastic pp cross section with the ATLAS detector at 8 and 13 TeV
No full textDiffraction 2016 conference tal
Determination of the total cross section and -parameter from elastic scattering in collisions at TeV with the ATLAS detector
No full textA new measurement of elastic scattering at TeV with the ATLAS-ALFA detector is presented. The measurement was performed using data recorded in a special run of the LHC with km. The elastic cross-section was measured differentially in the Mandelstam variable and from a fit to the total cross section, the -parameter and parameters of the nuclear slope are determined. The results for and are \begin{equation*} \sigma_{\textrm{tot}}(pp\rightarrow X) = \mbox{104.7} \; \pm 1.1 \; \mbox{mb} , \rho = \mbox{0.098} \; \pm 0.011 . \end{equation*} The energy evolution of and , connected through dispersion relations, is compared to several models. Furthermore, the total inelastic cross section is determined from the difference of the total and elastic cross section, and the ratio of the elastic to total cross section is calculated.A new measurement of elastic scattering at TeV with the ATLAS-ALFA detector is presented. The measurement was performed using data recorded in a special run of the LHC with km.
The elastic cross-section was measured differentially in the Mandelstam variable and from a fit to
the total cross section, the -parameter and parameters of the nuclear slope are determined.
The results for and are
\begin{equation*}
\sigma_{\textrm{tot}}(pp\rightarrow X) = \mbox{104.7} \; \pm 1.1 \; \mbox{mb} ,
\; \; \rho = \mbox{0.098} \; \pm 0.011 .
\end{equation*}
The energy evolution of and , connected through
dispersion relations, is compared to several models. Furthermore, the total inelastic
cross section is determined from the difference of the total and elastic cross section, and
the ratio of the elastic to total cross section is calculated.A new measurement of elastic scattering at TeV with the ATLAS-ALFA detector is presented. The measurement was performed using data recorded in a special run of the LHC with km. The elastic cross-section was measured differentially in the Mandelstam variable and from a fit to the total cross section, the -parameter and parameters of the nuclear slope are determined. The results for and are \begin{equation*} \sigma_{\textrm{tot}}(pp\rightarrow X) = \mbox{104.7} \; \pm 1.1 \; \mbox{mb} , \; \; \rho = \mbox{0.098} \; \pm 0.011 . \end{equation*} The energy evolution of and , connected through dispersion relations, is compared to several models. Furthermore, the total inelastic cross section is determined from the difference of the total and elastic cross section, and the ratio of the elastic to total cross section is calculated
