40 research outputs found
Effective Rheology of Bubbles Moving in a Capillary Tube
We calculate the average volumetric flux versus pressure drop of bubbles
moving in a single capillary tube with varying diameter, finding a square-root
relation from mapping the flow equations onto that of a driven overdamped
pendulum. The calculation is based on a derivation of the equation of motion of
a bubble train from considering the capillary forces and the entropy production
associated with the viscous flow. We also calculate the configurational
probability of the positions of the bubbles.Comment: 4 pages, 1 figur
Consequences of the introduction of the Russian red tree squirrel Sciurus vulgaris exalbidus (Pallas, 1778) to Omsk oblast
Rodent burrow network dynamics under human‐induced landscape transformation from desert to steppe in Kalmykian rangelands
Problems in estimation of the formation depth of hydrothermal deposits by data on pressure of mineralizing fluids
Modifications of a method for low energy gamma-ray incident angle reconstruction in the GAMMA-400 gamma-ray telescope
The GAMMA-400 gamma-ray telescope is designed to measure the gamma-ray fluxes in the energy range from 3c20 MeV to 3c1 TeV, performing a sensitive search for high-energy gamma-ray emission when annihilating or decaying dark matter particles. Such measurements will be also associated with the following scientific goals: searching for new and studying known Galactic and extragalactic discrete high-energy gamma-ray sources (supernova remnants, pulsars, accreting objects, microquasars, active galactic nuclei, blazars, quasars). It will be possible to study their structure with high angular resolution and measuring their energy spectra and luminosity with high-energy resolution; identify discrete gamma-ray sources with known sources in other energy ranges. The major advantage of the GAMMA-400 instrument is excellent angular and energy resolutions for gamma rays above 10 GeV. The gamma-ray telescope angular and energy resolutions for the main aperture at 100-GeV gamma rays are 3c0.01% and 3c1%, respectively. The motivation of presented results is to improve physical characteristics of the GAMMA-400 gamma-ray telescope in the energy range of 3c20-100 MeV, most unexplored range today. Such observations are crucial today for a number of high-priority problems faced by modern astrophysics and fundamental physics, including the origin of chemical elements and cosmic rays, the nature of dark matter, and the applicability range of the fundamental laws of physics. To improve the reconstruction accuracy of incident angle for low-energy gamma rays the special analysis of topology of pair-conversion events in thin layers of converter performed. Choosing the pair-conversion events with more precise vertical localization allows us to obtain significantly better angular resolution in comparison with previous and current space and ground-based experiments. For 50-MeV gamma rays the GAMMA-400 gamma-ray telescope angular resolution is better than 50
Spatial and Temporal Organization of Populations of the Bank Vole, Clethrionomys Glareolus
Hepatic nonparenchymal cells drive metastatic breast cancer outgrowth and partial epithelial to mesenchymal transition
NESTOR: a status report
NESTOR is an underwater neutrino astrophysics laboratory to be located
in the international waters of the southwest of Greece. The first phase
of this experiment is the construction and deployment of one hexagonal
tower consisting of 168 optical modules, with effective area of
20000m(2) for E greater than or equal to TeV neutrinos. Over the past
few years detailed studies of the site have been carried out while many
tests have been performed. The current status of the preparation of the
experiment and the future plans will be presented