| 1. |
- Schael, S., et al.
(author)
-
Electroweak measurements in electron positron collisions at W-boson-pair energies at LEP
- 2013
-
In: Physics Reports. - : Elsevier BV. - 0370-1573 .- 1873-6270. ; 532:4, s. 119-244
-
Research review (peer-reviewed)abstract
- Electroweak measurements performed with data taken at the electron positron collider LEP at CERN from 1995 to 2000 are reported. The combined data set considered in this report corresponds to a total luminosity of about 3 fb(-1) collected by the four LEP experiments ALEPH, DELPHI, 13 and OPAL, at centre-of-mass energies ranging from 130 GeV to 209 GeV. Combining the published results of the four LEP experiments, the measurements include total and differential cross-sections in photon-pair, fermion-pair and four-fermion production, the latter resulting from both double-resonant WW and ZZ production as well as singly resonant production. Total and differential cross-sections are measured precisely, providing a stringent test of the Standard Model at centre-of-mass energies never explored before in electron positron collisions. Final-state interaction effects in four-fermion production, such as those arising from colour reconnection and Bose Einstein correlations between the two W decay systems arising in WW production, are searched for and upper limits on the strength of possible effects are obtained. The data are used to determine fundamental properties of the W boson and the electroweak theory. Among others, the mass and width of the W boson, m(w) and Gamma(w), the branching fraction of W decays to hadrons, B(W -> had), and the trilinear gauge-boson self-couplings g(1)(Z), K-gamma and lambda(gamma), are determined to be: m(w) = 80.376 +/- 0.033 GeV Gamma(w) = 2.195 +/- 0.083 GeV B(W -> had) = 67.41 +/- 0.27% g(1)(Z) = 0.984(-0.020)(+0.018) K-gamma - 0.982 +/- 0.042 lambda(gamma) = 0.022 +/- 0.019. (C) 2013 Elsevier B.V. All rights reserved.
|
|
| 2. |
- Becker, Christiane, et al.
(author)
-
Nanophotonic enhanced perovskite-silicon solar cell devices
- 2019
-
In: ; , s. 858-859
-
Conference paper (peer-reviewed)abstract
- Perovskite-silicon tandem solar cells are a promising concept for overcoming the limits of conventional silicon single-junction technology. Light management is doubtless a key issue for further boosting efficiency. We discuss the impact of photonic nanostructures on the optical performance of perovskite-silicon devices. We experimentally and numerically demonstrate shallow antireflective nanotextures, which are compatible with perovskite solution processing. We further showcase enhanced photon up-conversion using perovskite nanoparticles interacting with photonic nanostructures and discuss the applicability for spectral conversion of sunlight.
|
|
| 3. |
- Becker, Christiane, et al.
(author)
-
Nanophotonic-Enhanced Two-Photon-Excited Photoluminescence of Perovskite Quantum Dots
- 2018
-
In: ACS Photonics. - : American Chemical Society (ACS). - 2330-4022. ; 5:11, s. 4668-4676
-
Journal article (peer-reviewed)abstract
- All-inorganic CsPbBr3 perovskite colloidal quantum dots have recently emerged as a promising material for a variety of optoelectronic applications, among others for multiphoton-pumped lasing. Nevertheless, high irradiance levels are generally required for such multiphoton processes. One strategy to enhance the multiphoton absorption is taking advantage of high local light intensities using photonic nanostructures. Here, we investigate two-photon-excited photoluminescence of CsPbBr3 perovskite quantum dots on a silicon photonic crystal slab. By systematic excitation of optical resonances using a pulsed near-infrared laser beam, we observe an enhancement of two-photon-pumped photoluminescence by more than 1 order of magnitude when comparing to using a bulk silicon film. Experimental and numerical analyses allow relating these findings to near-field enhancement effects on the nanostructured silicon surface. The results reveal a promising approach for significantly decreasing the required irradiance levels for multiphoton processes being of advantage in applications such as biomedical imaging, lighting, and solar energy.
|
|
| 4. |
- Bürger, Christoff, et al.
(author)
-
Using Reference Attribute Grammar-Controlled Rewriting for Energy Auto-Tuning
- 2015
-
In: CEUR Workshop Proceedings (CEUR-WS.org). - 1613-0073. ; 1474, s. 31-40
-
Conference paper (peer-reviewed)abstract
- Cyber-physical systems react on events reported by sensors and interact with objects of the real world according to their current state and their view of the world. This view is naturally represented by a model which is continuously analysed and updated at runtime. Model analyses should be ideally concise and efficient, requiring well-founded, comprehensible implementations with efficient reasoning mechanisms. In this paper, we apply reference attribute grammar controlled rewriting to concisely implement the runtime model of an auto-tuning case study for energy optimization. Attribute functions are used to interactively perform analyses. In case of an update, our system incrementally—and, thus, efficiently—recomputes depending analyses. Since reference attribute grammar controlled rewriting builds the required dependency graphs automatically, incremental analysis comes for free.
|
|
