Institution
Paul Scherrer Institute
Facility•Villigen, Switzerland•
About: Paul Scherrer Institute is a facility organization based out in Villigen, Switzerland. It is known for research contribution in the topics: Neutron & Large Hadron Collider. The organization has 9248 authors who have published 23984 publications receiving 890129 citations. The organization is also known as: PSI.
Topics: Neutron, Large Hadron Collider, Scattering, Catalysis, Aerosol
Papers published on a yearly basis
Papers
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TL;DR: The temporal and spatial stability of the first tunable femtosecond undulator hard-x-ray source for ultrafast diffraction and absorption experiments is reported and optical control of coherent lattice motion is demonstrated.
Abstract: We report on the temporal and spatial stability of the first tunable femtosecond undulator hard-x-ray source for ultrafast diffraction and absorption experiments. The 2.5-1 Angstrom output radiation is driven by an initial 50 fs laser pulse employing the laser-electron slicing technique. By using x-ray diffraction to probe laser-induced coherent optical phonons in bulk bismuth, we estimate an x-ray pulse duration of 140+/-30 fs FWHM with timing drifts below 30 fs rms measured over 5 days. Optical control of coherent lattice motion is demonstrated.
174 citations
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TL;DR: In this paper, the effect of rare-earth ions (La, Pr, Nd, and Gd) on the thermal behavior and on the catalytic activity for methane oxidation has been studied.
174 citations
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Advanced Technology Center1, Swiss Federal Institute of Aquatic Science and Technology2, Paul Scherrer Institute3, Air Force Research Laboratory4, University of Vienna5, University of California, Berkeley6, University of Maryland, College Park7, Space Telescope Science Institute8, ETH Zurich9, University of Oulu10, British Antarctic Survey11
TL;DR: In this article, the authors evaluate the probability of large-energy solar events by combining solar flare observations with an ensemble of stellar flare observations, and they conclude that solar flare energies form a relatively smooth distribution from small events to large flares, while flares on magnetically active, young Sun-like stars have energies and frequencies markedly in excess of strong solar flares.
Abstract: [1] The most powerful explosions on the Sun – in the form of bright flares, intense storms of solar energetic particles (SEPs), and fast coronal mass ejections (CMEs) – drive the most severe space-weather storms. Proxy records of flare energies based on SEPs in principle may offer the longest time base to study infrequent large events. We conclude that one suggested proxy, nitrate concentrations in polar ice cores, does not map reliably to SEP events. Concentrations of select radionuclides measured in natural archives may prove useful in extending the time interval of direct observations up to ten millennia, but as their calibration to solar flare fluences depends on multiple poorly known properties and processes, these proxies cannot presently be used to help determine the flare energy frequency distribution. Being thus limited to the use of direct flare observations, we evaluate the probabilities of large-energy solar events by combining solar flare observations with an ensemble of stellar flare observations. We conclude that solar flare energies form a relatively smooth distribution from small events to large flares, while flares on magnetically active, young Sun-like stars have energies and frequencies markedly in excess of strong solar flares, even after an empirical scaling with the mean coronal activity level of these stars. In order to empirically quantify the frequency of uncommonly large solar flares extensive surveys of stars of near-solar age need to be obtained, such as is feasible with the Kepler satellite. Because the likelihood of flares larger than approximately X30 remains empirically unconstrained, we present indirect arguments, based on records of sunspots and on statistical arguments, that solar flares in the past four centuries have likely not substantially exceeded the level of the largest flares observed in the space era, and that there is at most about a 10% chance of a flare larger than about X30 in the next 30 years.
174 citations
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TL;DR: In this article, a series of integrating nephelometers (M9003, Aurora 1000 and Aurora 3000) with newly designed light sources based on light emitting diodes are presented.
Abstract: . Integrating nephelometers are instruments that directly measure a value close to the light scattering coefficient of airborne particles. Different models of nephelometers have been used for decades for monitoring and research applications. Now, a series of nephelometers (Ecotech models M9003, Aurora 1000 and Aurora 3000) with newly designed light sources based on light emitting diodes are available. This article reports on the design of these integrating nephelometers and a comparison of the Aurora 3000 to another commercial instrument (TSI model 3563) that uses an incandescent lamp. Both instruments are three-wavelength, total and backscatter integrating nephelometers. We present a characterization of the new light source design of the Aurora 3000 and provide parameterizations for its angular sensitivity functions. These parameterizations facilitate to correct for measurement artefacts using Mie-theory. Furthermore, correction factors are provided as a function of the Angstrom exponent. Comparison measurements against the TSI 3563 with laboratory generated white particles and ambient air are also shown and discussed. Both instruments agree well within the calibration uncertainties and detection limit for total scattering with differences less than 5 %. Differences for backscattering are higher by up to 11 %. Highest differences were found for the longest wavelengths, where the signal to noise ratio is lowest. Differences at the blue and green wavelengths are less than 4 % and 3 %, respectively, for both total and backscattering.
174 citations
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174 citations
Authors
Showing all 9348 results
Name | H-index | Papers | Citations |
---|---|---|---|
Andrea Bocci | 172 | 2402 | 176461 |
Tobin J. Marks | 159 | 1621 | 111604 |
Wolfgang Wagner | 156 | 2342 | 123391 |
David D'Enterria | 150 | 1592 | 116210 |
Andreas Pfeiffer | 149 | 1756 | 131080 |
Christoph Grab | 144 | 1359 | 144174 |
Maurizio Pierini | 143 | 1782 | 104406 |
Alexander Belyaev | 142 | 1895 | 100796 |
Ajit Kumar Mohanty | 141 | 1124 | 93062 |
Felicitas Pauss | 141 | 1623 | 104493 |
Chiara Mariotti | 141 | 1426 | 98157 |
Luc Pape | 141 | 1441 | 130253 |
Rainer Wallny | 141 | 1661 | 105387 |
Roland Horisberger | 139 | 1471 | 100458 |
Emmanuelle Perez | 138 | 1550 | 99016 |