Search results for "ddc:530"
showing 10 items of 928 documents
A 3-Year Sample of Almost 1,600 Elves Recorded Above South America by the Pierre Auger Cosmic-Ray Observatory
2020
The time and location of the 1,598 verified and reconstructed elves, used for the analysis showcased in this paper, are publicly available on the website of the Pierre Auger Observatory (https://www.auger.org/ index.php/science/data). We wish to thank the World Wide Lightning Location Network (http://wwlln.net), a collaboration among over 50 universities and institutions, for providing the lightning location data used in this paper. We acknowledge Robert Marshall for providing one of the most advanced elve simulations to the public, a key tool in understanding the elves observed by the Pierre Auger Observatory. The successful installation, commissioning, and operation of the Pierre Auger Ob…
Observation of classically 'forbidden' electromagnetic wave propagation and implications for neutrino detection.
2018
Ongoing experimental efforts in Antarctica seek to detect ultra-high energy neutrinos by measurement of radio-frequency (RF) Askaryan radiation generated by the collision of a neutrino with an ice molecule. An array of RF antennas, deployed either in-ice or in-air, is used to infer the properties of the neutrino. To evaluate their experimental sensitivity, such experiments require a refractive index model for ray tracing radio-wave trajectories from a putative in-ice neutrino interaction point to the receiving antennas; this gives the degree of signal absorption or ray bending from source to receiver. The gradient in the density profile over the upper 200 meters of Antarctic ice, coupled wi…
Ultrafast structural changes within a photosynthetic reaction centre
2021
Nature <London> / Physical science 589, 310 - 314 (2021). doi:10.1038/s41586-020-3000-7
Rho resonance, timelike pion form factor, and implications for lattice studies of the hadronic vacuum polarization
2020
We study isospin-1 P-wave ππ scattering in lattice QCD with two flavors of O(a) improved Wilson fermions. For pion masses ranging from mπ=265 MeV to mπ=437 MeV, we determine the energy spectrum in the center-of-mass frame and in three moving frames. We obtain the scattering phase shifts using Lüscher’s finite-volume quantization condition. Fitting the dependence of the phase shifts on the scattering momentum to a Breit-Wigner form allows us to determine the corresponding ρ mass mρ and gρππ coupling. By combining the scattering phase shifts with the decay matrix element of the vector current, we calculate the timelike pion form factor, Fπ, and compare the results to the Gounaris-Sakurai repr…
Evidence for the production of three massive vector bosons with the ATLAS detector
2019
A search for the production of three massive vector bosons in proton–proton collisions is performed using data at TeV recorded with the ATLAS detector at the Large Hadron Collider in the years 2015–2017, corresponding to an integrated luminosity of 79.8 fb−1. Events with two same-sign leptons ℓ (electrons or muons) and at least two reconstructed jets are selected to search for . Events with three leptons without any same-flavour opposite-sign lepton pairs are used to search for , while events with three leptons and at least one same-flavour opposite-sign lepton pair and one or more reconstructed jets are used to search for . Finally, events with four leptons are analysed to search for and .…
Measurement of the W boson mass
1996
The W boson mass is measured using proton-proton collision data at root s = 13 TeV corresponding to an integrated luminosity of 1.7fb(-1) recorded during 2016 by the LHCb experiment. With a simultaneous fit of the muon q/p(T) distribution of a sample of W ->mu y decays and the phi* distribution of a sample of Z -> mu mu decays the W boson mass is determined to be
Constraints on off-shell Higgs boson production and the Higgs boson total width in ZZ → 4ℓ and ZZ → 2ℓ2ν final states with the ATLAS detector
2018
A measurement of off-shell Higgs boson production in the and decay channels, where ℓ stands for either an electron or a muon, is performed using data from proton–proton collisions at a centre-of-mass energy of TeV. The data were collected by the ATLAS experiment in 2015 and 2016 at the Large Hadron Collider, and they correspond to an integrated luminosity of . An observed (expected) upper limit on the off-shell Higgs signal strength, defined as the event yield normalised to the Standard Model prediction, of 3.8 (3.4) is obtained at 95% confidence level (CL). Assuming the ratio of the Higgs boson couplings to the Standard Model predictions is independent of the momentum transfer of the Higgs…
Relative proton and γ widths of astrophysically important states in 30S studied in the β-delayed decay of 31Ar
2013
Resonances just above the proton threshold in 30S affect the 29P(p,gamma)30S reaction under astrophysical conditions. The (p,gamma)-reaction rate is currently determined indirectly and depends on the properties of the relevant resonances. We present here a method for finding the ratio between the proton and gamma partial widths of resonances in 30S. The widths are determined from the beta-2p and beta-p-gamma decay of 31Ar, which is produced at the ISOLDE facility at the European research organization CERN. Experimental limits on the ratio between the proton and gamma partial widths for astrophysical relevant levels in 30S have been found for the first time. A level at 4688(5) keV is identif…
Towards large‐scale steady‐state enhanced nuclear magnetization with in situ detection
2021
Magnetic resonance in chemistry 59(12), 1208 - 1215 (2021). doi:10.1002/mrc.5161
Low-lying electric dipole gamma-continuum for the unstable Fe-62,64 nuclei : Strength evolution with neutron number
2020
6 pags., 4 figs.