University of Johannesburg

About: University of Johannesburg is a education organization based out in Johannesburg, South Africa. It is known for research contribution in the topics: Population & Tourism. The organization has 8070 authors who have published 22749 publications receiving 329408 citations. The organization is also known as: UJ.

Measurement of quarkonium production in proton-lead and proton-proton collisions at 5.02 TeV with the ATLAS detector

Abstract: The modification of the production of J/psi, psi(2S), and gamma (nS) (n = 1, 2, 3) in p+Pb collisions with respect to their production in pp collisions has been studied. The p+Pb and pp datasets us ...

Observation of electroweak production of a same-sign W boson pair in association with two jets in pp collisions at √s=13 TeV with the ATLAS detector

Abstract: This Letter presents the observation and measurement of electroweak production of a same-sign W boson pair in association with two jets using 36.1 fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of sqrt[s]=13 TeV by the ATLAS detector at the Large Hadron Collider. The analysis is performed in the detector fiducial phase-space region, defined by the presence of two same-sign leptons, electron or muon, and at least two jets with a large invariant mass and rapidity difference. A total of 122 candidate events are observed for a background expectation of 69±7 events, corresponding to an observed signal significance of 6.5 standard deviations. The measured fiducial signal cross section is σ^{fid}=2.89_{-0.48}^{+0.51}(stat)_{-0.28}^{+0.29}(syst) fb.

Sequence stratigraphic development of the Neoarchean Transvaal carbonate platform, Kaapvaal Craton, South Africa

Abstract: The similar to 2.67 to similar to 2.46 Ga lower Transvaal Supergroup, South Africa, consists of a mixed siliciclastic-carbonate ramp that grades upward into an extensive carbonate platform, overlain by deep subtidal banded iron-formation. It is composed of 14 third-order sequences that develop from a mixed siliciclastic-carbonate ramp to a steepened margin followed by a rimmed margin that separated lagoonal environments from the open ocean. Drowning of the platform coincided with deposition of banded iron-formation across the Kaapvaal Craton. The geometry and stacking of these sequences are consistent with more recent patterns of carbonate accumulation, demonstrating that Neoarchean carbonate accumulation responded to subsidence, sea level change, and carbonate production similarly to Proterozoic and Phanerozoic platforms. The similarity of carbonate platform geometry through time, even with significant changes in dominant biota, demonstrates that rimmed margins are localized primarily by physiochemical conditions rather than growth dynamics of specific organisms. Stratigraphic patterns during deposition of the Schmidtsdrift and Campbellrand-Malmani subgroups are most consistent with variable thinning of the Kaapvaal Craton during extrusion of the similar to 2.7 Ga Ventersdorp lavas. Although depositional patterns are consistent with rifting of the western margin of the Kaapvaal Craton during this time, a rift-to-drift transition is not required to explain subsidence. Heating and thinning during Ventersdorp time can produce the observed thermal subsidence from similar to 2.7 to similar to 2.45 Ga if the thermal diffusivity of the craton was moderately low.