Search results for "high [energy resolution]"
showing 10 items of 20300 documents
Measurement of dielectron production in central Pb-Pb collisions at √sNN = 2.76 TeV
2019
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. The first measurement of dielectron (e + e −) production in central (0 – 10 %) Pb – Pb collisions at √sNN=2.76TeV at the LHC is presented. The dielectron invariant-mass spectrum is compared to the expected contributions from hadron decays in the invariant-mass range 0 < mee < 3.5 GeV / c2. The ratio of data and the cocktail of hadronic contributions without vacuum ρ0 is measured in the invariant-mass range 0.15 < mee < 0.7 GeV / c2, w…
Adventiv-Embryonen aus Nicotiana-kallus, der bei Hohen Lichtintensitäten Kultiviert wurde
1965
The formation of embryonic structures in Nicotiana callus tissue has been reported. High intensity of light as a stimulating factor in differentiation is discussed.
The ALICE experiment at the CERN LHC
2008
Journal of Instrumentation 3(08), S08002 (2008). doi:10.1088/1748-0221/3/08/S08002
Few-body insights of multiquark exotic hadrons
2018
In this contribution we discuss the adequate treatment of the $4-$ and $5-$body dynamics within a constituent quark framework. We stress that the variational and Born-Oppenheimer approximations give energies rather close to the exact ones, while the diquark approximation might be rather misleading. Hall-Post inequalities provide very useful lower bounds that exclude possible stable states for some mass ratios and color wave functions.
Measurement of parity-violating spin asymmetries in W± production at midrapidity in longitudinally polarized p+p collisions
2016
We present midrapidity measurements from the PHENIX experiment of large parity-violating singlespin asymmetries of high transverse momentum electrons and positrons from W =Z decays, produced in longitudinally polarized p þ p collisions at center of mass energies of ffiffi s p ¼ 500 and 510 GeV. These asymmetries allow direct access to the antiquark polarized parton distribution functions due to the parityviolating nature of the W-boson coupling to quarks and antiquarks. The results presented are based on data collected in 2011, 2012, and 2013 with an integrated luminosity of 240 pb−1, which exceeds previous PHENIX published results by a factor of more than 27. These high Q2 data probe the p…
Lęk i stres - jak radzą sobie z nimi policjanci? Wyniki badań własnych
2018
W artykule przedstawiono wyniki badań dotyczących lęku jako aktualnego stanu bądź jako cechy osobowości, poziomu odczuwanego stresu oraz sposobów radzenia sobie z nim przez policjantów Wydziału Kryminalnego oraz Prewencji i Ruchu Drogowego. Założenia dotyczące celu badania wskazywały na wyższy poziom lęku i stresu u policjantów Wydziału Kryminalnego. Hipotezy te związane były z charakterem pracy mundurowych danego oddziału. Na charakter owej specjalizacji służbowej wpływają warunki środowiskowe pracy, dynamiczność zmian, obecność czynników kryminogennych oraz waga zadań mających na celu zwalczanie przestępczości kryminalnej. Im więcej czynników zagrożenia, tym lepsze powinny być strategie z…
The Large Observatory For x-ray Timing
2014
The Large Observatory For x-ray Timing (LOFT) was studied within ESA M3 Cosmic Vision framework and participated in the final down-selection for a launch slot in 2022-2024. Thanks to the unprecedented combination of effective area and spectral resolution of its main instrument, LOFT will study the behaviour of matter under extreme conditions, such as the strong gravitational field in the innermost regions of accretion flows close to black holes and neutron stars, and the supra-nuclear densities in the interior of neutron stars. The science payload is based on a Large Area Detector (LAD, 10 m 2 effective area, 2-30 keV, 240 eV spectral resolution, 1 deg collimated field of view) and a WideFi…
The XENON1T Dark Matter Experiment
2017
The XENON1T experiment at the Laboratori Nazionali del Gran Sasso (LNGS) is the first WIMP dark matter detector operating with a liquid xenon target mass above the ton-scale. Out of its 3.2 t liquid xenon inventory, 2.0 t constitute the active target of the dual-phase time projection chamber. The scintillation and ionization signals from particle interactions are detected with low-background photomultipliers. This article describes the XENON1T instrument and its subsystems as well as strategies to achieve an unprecedented low background level. First results on the detector response and the performance of the subsystems are also presented. © 2017, The Author(s).
Search for inelastic scattering of WIMP dark matter in XENON1T
2021
We report the results of a search for the inelastic scattering of weakly interacting massive particles (WIMPs) in the XENON1T dark matter experiment. Scattering off $^{129}$Xe is the most sensitive probe of inelastic WIMP interactions, with a signature of a 39.6 keV de-excitation photon detected simultaneously with the nuclear recoil. Using an exposure of 0.89 tonne-years, we find no evidence of inelastic WIMP scattering with a significance of more than 2$\sigma$. A profile-likelihood ratio analysis is used to set upper limits on the cross-section of WIMP-nucleus interactions. We exclude new parameter space for WIMPs heavier than 100 GeV/c${}^2$, with the strongest upper limit of $3.3 \time…
Search for Light Dark Matter Interactions Enhanced by the Migdal Effect or Bremsstrahlung in XENON1T.
2019
Direct dark matter detection experiments based on a liquid xenon target are leading the search for dark matter particles with masses above ∼5 GeV/c2, but have limited sensitivity to lighter masses because of the small momentum transfer in dark matter-nucleus elastic scattering. However, there is an irreducible contribution from inelastic processes accompanying the elastic scattering, which leads to the excitation and ionization of the recoiling atom (the Migdal effect) or the emission of a bremsstrahlung photon. In this Letter, we report on a probe of low-mass dark matter with masses down to about 85 MeV/c2 by looking for electronic recoils induced by the Migdal effect and bremsstrahlung us…