Properties of the Higgs boson are measured in the two-photon final state using 36.1 fb$^{-1}$ of proton-proton collision data recorded at $\sqrt{s} = 13$ TeV by the ATLAS experiment at the Large Hadron Collider. Cross-section measurements for the production of a Higgs boson through gluon-gluon fusion, vector-boson fusion, and in association with a vector bosonor a top-quark pair are reported. The signal strength, defined as the ratio of the observed to the expected signal yield, is measured for each of these production processes as well as inclusively. The global signal strength measurement of $0.99 \pm 0.14$ improves on the precision of the ATLAS measurement at $\sqrt{s} = 7$ and 8 TeV by a factor of two. Measurements of gluon-gluon fusion and vector-boson fusion productions yield signal strengths compatible with the Standard Model prediction. Measurements of simplified template cross sections, designed to quantify the different Higgs boson production processes in specific regions of phase space, are reported. The cross section for the production of the Higgs boson decaying to two isolated photons in a fiducial region closely matching the experimental selection of the photons is measured to be $55 \pm 10$ fb, which is in good agreement with the Standard Model prediction of $64 \pm 2$ fb. Furthermore, cross sections in fiducial regions enriched in Higgs boson production in vector-boson fusion or in association with large missing transverse momentum, leptons or top-quark pairs are reported. Differential and double-differential measurements are performed for several variables related to the diphoton kinematics as well as the kinematics and multiplicity of the jets produced in association with a Higgs boson. No significant deviations from a wide array of Standard Model predictions are observed.
Measured differential cross section with associated uncertainties as a function of PT(2GAMMA). Each systematic uncertainty sources is fully uncorrelated with the other sources and fully correlated across bins, except for the background modelling systematics for which an uncorrelated treatment across bins is more appropriate.
Measured differential cross section with associated uncertainties as a function of YRAP(2GAMMA). Each systematic uncertainty sources is fully uncorrelated with the other sources and fully correlated across bins, except for the background modelling systematics for which an uncorrelated treatment across bins is more appropriate.
Measured differential cross section with associated uncertainties as a function of PTTHRUST(2GAMMA). Each systematic uncertainty sources is fully uncorrelated with the other sources and fully correlated across bins, except for the background modelling systematics for which an uncorrelated treatment across bins is more appropriate.
Inclusive event-shape variables have been measured in the current region of the Breit frame for neutral current deep inelastic ep scattering using an integrated luminosity of 45.0 pb^-1 collected with the ZEUS detector at HERA. The variables studied included thrust, jet broadening and invariant jet mass. The kinematic range covered was 10 < Q^2 < 20,480 GeV^2 and 6.10^-4 < x < 0.6, where Q^2 is the virtuality of the exchanged boson and x is the Bjorken variable. The Q dependence of the shape variables has been used in conjunction with NLO perturbative calculations and the Dokshitzer-Webber non-perturbative corrections (`power corrections') to investigate the validity of this approach.
Mean value of the event shape variables 1-THRUST(C=T) in different Q**2 and X bins.
Mean value of the event shape variables B(C=T) in different Q**2 and X bins.
Mean value of the event shape variables RHO**2 in different Q**2 and X bins.
We report differential cross sections for the production of D*(2010) produced in 500 GeV/c pi^- nucleon interactions from experiment E791 at Fermilab, as functions of Feynman-x (x_F) and transverse momentum squared (p_T^2). We also report the D* +/- charge asymmetry and spin-density matrix elements as functions of these variables. Investigation of the spin-density matrix elements shows no evidence of polarization. The average values of the spin alignment are \eta= 0.01 +- 0.02 and -0.01 +- 0.02 for leading and non-leading particles, respectively.
Acceptance corrected differential cross sections for D*+- production as a function of XL, Feynman X.
Acceptance corected differential cross sections for D*+- production as a function of PT**2.
Charge production asymmetry as a function of Feynman X.
A measurement of the spin alignment of charged D^* mesons produced in continuum e^+ e^- \to c \bar{c} events at \sqrt{s}=10.5 GeV is presented. This study using 4.72 fb^{-1} of CLEO II data shows that there is little evidence of any D^* spin alignment.
Systematic errors are not given.
Systematic errors are not given.
Two decay modes of D0 --> K- PI+ and D0 --> K- PI+ PI0 are combined.
The spin density matrix elements for the ϱ 0 , K ∗0 (892) and F produced in hadronic Z 0 decays are measured in the DELPHI detector. There is no evidence for spin alignment of the K ∗0 (892) and F in the region x p ≤ 0.3 ( x p = p p beam ), where ϱ 00 = 0.33 ± 0.05 and ϱ 00 = 0.30 ± 0.04, respectively. In the fragmentation region, x p ≥ 0.4, there is some indication for spin alignment of the ϱ 0 and K ∗0 (892), since ϱ 00 = 0.43 ± 0.05 and ϱ 00 = 0.46 ± 0.08, respectively. These values are compared with those found in meson-induced hadronic reactions. For the F, ϱ 00 = 0.30 ± 0.04 for x p ≥ 0.4 and 0.55 ± 0.10 for x p ≥ 0.7. The off-diagonal spin density matrix element ϱ 1-1 is consistent with zero in all cases.
Helicity density matrices elements. The statistical and systematic errors are combined quadratically.
Helicity density matrices elements. The statistical and systematic errors are combined quadratically.
Helicity density matrices elements. The statistical and systematic errors are combined quadratically.
We present a summary of the physics results from an experimental study of the reaction π−p→π−π+n at 100 and 175 GeV/c incident-beam momentum. Our data show the continuing dominance of one-pion exchange in these reactions with the characteristic 1Plab2 momentum dependence. We extract the pion Regge trajectory from our data on π−p→ρ0n and study the zero structure of the ππ differential cross section up to sππ=12 GeV2.
No description provided.
No description provided.
SPHERICAL HARMONIC MOMENTS.
The reaction π−p→K0K−p has been measured from 50 to 175 GeV/c. The production characteristics of the A2 have been analyzed. We find spin and t dependence similar to lower energies, but the cross section falls rapidly with energy. In a Regge description of π−p→A2−p our data imply a rather small Pomeron-exchange component.
No description provided.
RAW CROSS SECTION WITHIN MASS CUTS.
No description provided.
We present the results of a systematic analysis of charge-exchange double dissociation in proton-proton collisions at the CERN Intersecting Storage Rings. The data, obtained with the Split-Field Magnet detector, cover the entire ISR energy range between s = 23 GeV and s = 63 GeV at five standard energies.
CHARGE EXCHANGE DOUBLE DIFFRACTION DISSOCIATION OF PROTONS. THESE CROSS SECTIONS WERE REPORTED IN G. GOGGI ET AL., PL 72B, 265 (1977).
No description provided.
THE SEMI INCLUSIVE DENSITY MATRICES ARE ALSO GIVEN (P P --> DEL++ P PI- + DEL0 P PI+).
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