95 research outputs found
A Biased Review of Sociophysics
Various aspects of recent sociophysics research are shortly reviewed:
Schelling model as an example for lack of interdisciplinary cooperation,
opinion dynamics, combat, and citation statistics as an example for strong
interdisciplinarity.Comment: 16 pages for J. Stat. Phys. including 2 figures and numerous
reference
Observation of inverse Compton emission from a long γ-ray burst.
Long-duration γ-ray bursts (GRBs) originate from ultra-relativistic jets launched from the collapsing cores of dying massive stars. They are characterized by an initial phase of bright and highly variable radiation in the kiloelectronvolt-to-megaelectronvolt band, which is probably produced within the jet and lasts from milliseconds to minutes, known as the prompt emission1,2. Subsequently, the interaction of the jet with the surrounding medium generates shock waves that are responsible for the afterglow emission, which lasts from days to months and occurs over a broad energy range from the radio to the gigaelectronvolt bands1-6. The afterglow emission is generally well explained as synchrotron radiation emitted by electrons accelerated by the external shock7-9. Recently, intense long-lasting emission between 0.2 and 1 teraelectronvolts was observed from GRB 190114C10,11. Here we report multi-frequency observations of GRB 190114C, and study the evolution in time of the GRB emission across 17 orders of magnitude in energy, from 5 × 10-6 to 1012 electronvolts. We find that the broadband spectral energy distribution is double-peaked, with the teraelectronvolt emission constituting a distinct spectral component with power comparable to the synchrotron component. This component is associated with the afterglow and is satisfactorily explained by inverse Compton up-scattering of synchrotron photons by high-energy electrons. We find that the conditions required to account for the observed teraelectronvolt component are typical for GRBs, supporting the possibility that inverse Compton emission is commonly produced in GRBs
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Corrected thermal conductivity of liquids by the ac-heated wire method (Dowtherm A and Isopar M)
The thermal conductivity of Dowtherm A and of Isopar M was redetermined by the method employing low-frequency alternating current in very fine wires, and found to be higher than formerly reported and in agreement with other literature values or indications. It seems likely that the results reported for Dowtherm E, Dow-Corning 710 Fluid and Union Carbide Wquid G are also erroneous. However, the results for NO/sub 2/ --N/sub 2//sub 4/ undoubtedly correct, and with careful work it seems evident that good results can be obtained with any liquids that are electrical insulators or poor conductors. Nevertheless, the former conclusion that the added complexity of the method does not justify its use except at the high temperatures at which radiation is important, still seems valid. (auth
Acceleration of alpha particles by the space radiation effects laboratory synchro-cyclotron
Phenotypic responses of chickens to long-term, bidirectional selection for juvenile body weight—Historical perspective
Types of Inadequate Interviewer Behaviour in Survey Interviews; Their Causes and Effects 1
Antibody Response of Chickens to Sheep Red Blood Cells: Crosses Among Divergently Selected Lines and Relaxed Sublines
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