2,970 research outputs found
SKYWAY '09: Awareness of the Sky/ The Sky as Awareness - International Light Festival, Impressions and Reflections on the Proceedings
Two artists, two astrophysicists, a historian of science, a musician, the Skyway Festival director and the Toruń 2016 director met over two days on the 15th and 16th of August in this beautiful gothic city to discuss the relationship between art and astrophysics. The aim of the sessions was to foster interdisciplinary understanding and achieve a consensus on methods and approaches for future collaborative work and cross-disciplinary production of art, writing and dissemination.Peer reviewe
Deformations of calibrated subbundles of Euclidean spaces via twisting by special sections
We extend the "bundle constructions" of calibrated submanifolds, due to
Harvey--Lawson in the special Lagrangian case, and to
Ionel--Karigiannis--Min-Oo in the cases of exceptional calibrations, by
"twisting" the bundles by a special (harmonic, holomorphic, parallel) section
of a complementary bundle. The existence of such deformations shows that the
moduli space of calibrated deformations of these "calibrated subbundles"
includes deformations which destroy the linear structure of the fibre.Comment: 16 pages, no figures. Version 2: Only minor cosmetic and
typographical revisions. To appear in "Annals of Global Analysis and
Geometry.
Spectral and Spin Measurement of Two Small and Fast-Rotating Near-Earth Asteroids
In May 2012 two asteroids made near-miss "grazing" passes at distances of a
few Earth-radii: 2012 KP24 passed at nine Earth-radii and 2012 KT42 at only
three Earth-radii. The latter passed inside the orbital distance of
geosynchronous satellites. From spectral and imaging measurements using NASA's
3-m Infrared Telescope Facility (IRTF), we deduce taxonomic, rotational, and
physical properties. Their spectral characteristics are somewhat atypical among
near-Earth asteroids: C-complex for 2012 KP24 and B-type for 2012 KT42, from
which we interpret the albedos of both asteroids to be between 0.10 and 0.15
and effective diameters of 20+-2 and 6+-1 meters, respectively. Among B-type
asteroids, the spectrum of 2012 KT42 is most similar to 3200 Phaethon and 4015
Wilson-Harrington. Not only are these among the smallest asteroids spectrally
measured, we also find they are among the fastest-spinning: 2012 KP24 completes
a rotation in 2.5008+-0.0006 minutes and 2012 KT42 rotates in 3.634+-0.001
minutes.Comment: 4 pages, 3 figures, accepted for publication in Icaru
Referencing Sources of Molecular Spectroscopic Data in the Era of Data Science: Application to the HITRAN and AMBDAS Databases
The application described has been designed to create bibliographic entries
in large databases with diverse sources automatically, which reduces both the
frequency of mistakes and the workload for the administrators. This new system
uniquely identifies each reference from its digital object identifier (DOI) and
retrieves the corresponding bibliographic information from any of several
online services, including the SAO/NASA Astrophysics Data Systems (ADS) and
CrossRef APIs. Once parsed into a relational database, the software is able to
produce bibliographies in any of several formats, including HTML and BibTeX,
for use on websites or printed articles. The application is provided
free-of-charge for general use by any scientific database. The power of this
application is demonstrated when used to populate reference data for the HITRAN
and AMBDAS databases as test cases. HITRAN contains data that is provided by
researchers and collaborators throughout the spectroscopic community. These
contributors are accredited for their contributions through the bibliography
produced alongside the data returned by an online search in HITRAN. Prior to
the work presented here, HITRAN and AMBDAS created these bibliographies
manually, which is a tedious, time-consuming and error-prone process. The
complete code for the new referencing system can be found at
\url{https://github.com/hitranonline/refs}.Comment: 11 pages, 5 figures, already published online at
https://doi.org/10.3390/atoms802001
A meta-analysis of the impact of traffic-related air pollution on health and the factors affecting exposure
ISSN 1743-354
Mobile radio interferometric geodetic systems
Operation of the Astronomical Radio Interferometric Earth Surveying (ARIES) in a proof of concept mode is discussed. Accuracy demonstrations over a short baseline, a 180 km baseline, and a 380 km baseline are documented. Use of ARIES in the Sea Slope Experiment of the National Geodetic Survey to study the apparent differences between oceanographic and geodetic leveling determinations of the sea surface along the Pacific Coast is described. Intergration of the NAVSTAR Global Positioning System and a concept called SERIES (Satellite Emission Radio Interferometric Earth Surveying) is briefly reviewed
Seasonal, Taxonomic, and Local Habitat Components of Bird-window Collisions on an Urban University Campus in Cleveland, OH
Author Institution: Department of Biological, Geological & Environmental Sciences, Cleveland State UniversityAuthor Institution: Department of Ornithology, Cleveland Museum of Natural HistoryMigrating birds congregate near the shores of Lake Erie during migration and may be funneled through small green spaces within the urban matrix of Great Lake coastal cities, where they are at risk of higher mortality from manmade structures. Bird deaths due to window collisions were assessed amongst a complex of low-rise buildings (<30 m) on a university campus in Cleveland,
OH. A 1.8 km route was surveyed three times per week during a 12-month period. Deaths were tested against null hypotheses that season, taxonomy, and building attributes had no significant relationship with avian mortality. We recovered 271 dead birds of 50 species, all of which were consistent with regional bird lists and Neotropical-Nearctic and North American migrants through Ohio. Deaths occurred non-randomly by week, month, and migratory status with 90 percent of deaths occurring during spring and fall migrations. Consequently, migrants (warblers: 34 percent of species richness, 30 percent of deaths; sparrows: 14 percent
of richness, 35 percent of deaths) were observed nine times more frequently than residents. Neotropical-Nearctic migrant species outnumbered North American migrant species. Although there was no statistical difference between the compass direction of a building facade and the number of deaths, deaths were not randomly distributed among campus buildings. Rather, significantly more deaths occurred at facades with higher percentages of glass. The presence of trees within 5 m of a window and the reflection of trees in windows were also associated with a greater risk of fatality. A better understanding of the factors associated with bird-window collisions is a pressing issue in the conservation of migratory birds
Electrostatic Patch Effect in Cylindrical Geometry. I. Potential and Energy between Slightly Non-Coaxial Cylinders
We study the effect of any uneven voltage distribution on two close
cylindrical conductors with parallel axes that are slightly shifted in the
radial and by any length in the axial direction. The investigation is
especially motivated by certain precision measurements, such as the Satellite
Test of the Equivalence Principle (STEP). By energy conservation, the force can
be found as the energy gradient in the vector of the shift, which requires
determining potential distribution and energy in the gap. The boundary value
problem for the potential is solved, and energy is thus found to the second
order in the small transverse shift, and to lowest order in the gap to cylinder
radius ratio. The energy consists of three parts: the usual capacitor part due
to the uniform potential difference, the one coming from the interaction
between the voltage patches and the uniform voltage difference, and the energy
of patch interaction, entirely independent of the uniform voltage. Patch effect
forces and torques in the cylindrical configuration are derived and analyzed in
the next two parts of this work.Comment: 26 pages, 1 Figure. Submitted to Classical and Quantum Gravit
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