We present data on the five final states Λω, Λφ, Λϱ 0 , Σ 0 ⊘ and Σ 0 ϱ 0 produced in 3.1–3.6 GeV/ c K − p interactions. These data are from a bubble chamber experiment with 18 events/μb. For all reactions the data consist of the overall and differetial cross sections, and the hyperon polarisation and the vector meson's density matrix elements as a function of momentum transfer. For Λω and Λ⊘, an almost complete amplitude analysis is performed in several regions of momentum transfer. The data are examined from the point of view of various exchange models.
CORRECTED FOR UNSEEN DECAY MODES OF LAMBDA, OMEGA AND PHI.
No description provided.
NO BACKWARD PHI PRODUCTION.
The α-proton elastic scattering has been measured with α particles at equivalent incident proton energies of 438, 648, and 1036 MeV. A structure is observed at the position where a second minimum is expected in the differential cross section. Comparison with improved versions of the Glauber model are presented.
X ERROR D(THETA) = 0.4400 DEG.
X ERROR D(THETA) = 0.2200 DEG.
X ERROR D(THETA) = 0.4400 DEG.
The angular distribution of the inclusive reaction 4 He + p → 3 He + X was measured with 6.85 GeV/ c incident alphas. At large angles, the observed kinematics corresponds to the elastic scattering on the target proton of an 3 He present in the incoming 4 He, the remaining neutron being a spectator. This shows the presence of an important component of 3 He in 4 He. The integrated cross section for 3 He production is σ 3He = 24.1 ± 1.9 mb.
No description provided.
Incident alphas on protons were used to measure the elastic cross section in the backward hemisphere at 3.20, 4.00, 5.08 and 6.00 GeV/ c . The level and shape of the angular distributions are strongly dependent on energy. A backward peak shows up at 4.00 GeV/ c and become much steeper when the energy increases.
X ERROR H = 0.50 G/CM**2. X ERROR D(THETA) = 0.8800 DEG.
X ERROR H = 0.50 G/CM**2. X ERROR D(THETA) = 0.4400 DEG.
X ERROR H = 0.50 G/CM**2. X ERROR D(THETA) = 0.8800 DEG.
Emission of intermediate mass fragments (IMFs) (Z>~3) from central collisions of 40Ar+45Sc (E/A=35–115 MeV), 58Ni+58Ni (E/A=35–105 MeV), and 86Kr+93Nb (E/A=35–95 MeV) was studied. For each system, the average number of IMFs per event increased with beam energy, reached a maximum, and then decreased. The beam energy of peak IMF production increased linearly with the combined mass of the system. The number of IMFs emitted at the peak also increased with the system mass. Percolation calculations showed a weaker dependence of the peak beam energy and the number of IMFs on the total mass of the system.
Uncertainty in EKIN is 1 PCT.
The latest neutron electric dipole moment (EDM) experiment has been collecting data at the Institut Laue-Langevin (ILL), Grenoble, since 1996. It uses an atomic-mercury magnetometer to compensate for the magnetic field fluctuations that were the principal source of systematic errors in previous experiments. The first results, in combination with the previous ILL measurement, yield a possible range of values of (−7.0<dn<5.0)×10−26ecm ( 90% C.L.). This may be interpreted as an upper limit on the absolute value of the neutron EDM of |dn|<6.3×10−26ecm ( 90% C.L.).
No description provided.
Dijet events are studied in the proton--proton collision dataset recorded at $\sqrt{s}=$13 TeV with the ATLAS detector at the Large Hadron Collider in 2015 and 2016, corresponding to integrated luminosities of 3.5 fb$^{-1}$ and 33.5 fb$^{-1}$ respectively. Invariant mass and angular distributions are compared to background predictions and no significant deviation is observed. For resonance searches, a new method for fitting the background component of the invariant mass distribution is employed. The dataset is then used to set upper limits at a 95% confidence level on a range of new physics scenarios. Excited quarks with masses below 6.0 TeV are excluded, and limits are set on quantum black holes, heavy W' bosons, W* bosons, and a range of masses and couplings in a Z' dark matter mediator model. Model-independent limits on signals with a Gaussian shape are also set, using a new approach allowing factorization of physics and detector effects. From the angular distributions, a scale of new physics in contact interaction models is excluded for scenarios with either constructive or destructive interference. These results represent a substantial improvement over those obtained previously with lower integrated luminosity.
The number of events as a function of the dijet invariant mass, compared to background prediction from fit and corresponding uncertainties, in the region defined by |y*|<0.6
The number of events as a function of the dijet invariant mass, compared to background prediction from fit and corresponding uncertainties, in the region defined by |y*|<0.6
The number of events as a function of the dijet invariant mass, compared to background prediction from fit and corresponding uncertainties, in the region defined by |y*|<1.2 optimized for the W* search.
A search is presented for the direct pair production of the stop, the supersymmetric partner of the top quark, that decays through an $R$-parity-violating coupling to a final state with two leptons and two jets, at least one of which is identified as a $b$-jet. The dataset corresponds to an integrated luminosity of 36.1 fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of $\sqrt{s} = 13$ TeV, collected in 2015 and 2016 by the ATLAS detector at the LHC. No significant excess is observed over the Standard Model background, and exclusion limits are set on stop pair production at a 95% confidence level. Lower limits on the stop mass are set between 600 GeV and 1.5 TeV for branching ratios above 10% for decays to an electron or muon and a $b$-quark.
Signal acceptance (in %) in the (BRe,BRtau) plane for a 800 GeV stop, for the SR800 signal region.
Expected exclusion limit contour in the (BRe,BRtau) plane for a 600 GeV stop. All limits are computed at 95% CL.
Expected exclusion limit contour in the (BRe,BRtau) plane for a 600 GeV stop. All limits are computed at 95% CL.
A search is conducted for new resonances decaying into a $W$ or $Z$ boson and a 125 GeV Higgs boson in the $\nu\bar{\nu}b\bar{b}$, $\ell^{\pm}{\nu}b\bar{b}$, and $\ell^+\ell^-b\bar{b}$ final states, where $\ell ^{\pm}= e^{\pm}$ or $\mu^{\pm}$, in $pp$ collisions at $\sqrt s = 13$ TeV. The data used correspond to a total integrated luminosity of 36.1 fb$^{-1}$ collected with the ATLAS detector at the Large Hadron Collider during the 2015 and 2016 data-taking periods. The search is conducted by examining the reconstructed invariant or transverse mass distributions of $Wh$ and $Zh$ candidates for evidence of a localised excess in the mass range of 220 GeV up to 5 TeV. No significant excess is observed and the results are interpreted in terms of constraints on the production cross-section times branching fraction of heavy $W^\prime$ and $Z^\prime$ resonances in heavy-vector-triplet models and the CP-odd scalar boson $A$ in two-Higgs-doublet models. Upper limits are placed at the 95 % confidence level and range between $9.0\times 10^{-4}$ pb and $8.1\times 10^{-1}$ pb depending on the model and mass of the resonance.
Upper limits on Zprime to Z h production cross section x branching fraction in pb
Upper limits on Zprime to Z h production cross section x branching fraction in pb
Upper limits on Wprime to W h production cross section x branching fraction in pb
Several extensions of the Standard Model predict associated production of dark-matter particles with a Higgs boson. Such processes are searched for in final states with missing transverse momentum and a Higgs boson decaying to a $b\bar b$ pair with the ATLAS detector using 36.1 fb$^{-1}$ of $pp$ collisions at a center-of-mass energy of 13 TeV at the LHC. The observed data are in agreement with the Standard Model predictions and limits are placed on the associated production of dark-matter particles and a Higgs boson.
Distributions of the invariant mass of the Higgs boson candidates mh=m_J with one b-tag in the SR for the fourth MET category which is used as input to the fit.
Distributions of the invariant mass of the Higgs boson candidates mh=m_jj with two b-tags in the SR for the first MET category that is used as input to the fit.
Distributions of the invariant mass of the Higgs boson candidates mh=m_jj with two b-tags in the SR for the second MET category that is used as input to the fit.
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