1,164,149 research outputs found
The first WASP public data release
The WASP (wide angle search for planets) project is an exoplanet transit survey that has been automatically taking wide field images since 2004. Two instruments, one in La Palma and the other in South Africa, continually monitor the night sky, building up light curves of millions of unique objects. These light curves are used to search for the characteristics of exoplanetary transits. This first public data release (DR1) of the WASP archive makes available all the light curve data and images from 2004 up to 2008 in both the Northern and Southern hemispheres. A web interface () to the data allows easy access over the Internet. The data set contains 3 631 972 raw images and 17 970 937 light curves. In total the light curves have 119 930 299 362 data points available between them
The relationships between resource ratios and phytoplankton composition during the spring period in five North German lakes
Phytoplankton species composition and the availability of potentially limiting resources were investigatcd in five northern German lakes (Suhrer See, Kellersee, Behler See, PluBsee, and Krummsee) during spring 1988. Species composition was related to resource ratios to test Tilman’s resource-ratio hypothesis. The clearest results were obtained for Aulacoseira spp. Both the time-courses within the lakes and the comparison among the lakes suggest a strong tendency of this genus to become dominant at high Si : light ratios. Fragilariaceae occupied the next position on the Si : light gradient. Such conditions permitted them to become important even when Si : P ratios were quite low. With the onset of stratification diatoms were replaced by flagellates
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Natural History Note Differential Response To Circularly Polarized Light By The Jewel Scarab Beetle Chrysina Gloriosa
Circularly polarized light is rare in the terrestrial environment, and cuticular reflections from scarab beetles are one of the few natural sources. Chrysina gloriosa LeConte 1854, a scarab beetle found in montane juniper forests of the extreme southwestern United States and northern Mexico, are camouflaged in juniper foliage; however, when viewed with right circularly polarizing filters, the beetles exhibit a stark black contrast. Given the polarization-specific changes in the appearance of C. gloriosa, we hypothesized that C. gloriosa can detect circularly polarized light. We tested for phototactic response and differential flight orientation of C. gloriosa toward different light stimuli. Chrysina gloriosa exhibited (a) positive phototaxis, (b) differential flight orientation between linear and circularly polarized light stimuli of equal intensities, and (c) discrimination between circularly polarized and unpolarized lights of different intensities consistent with a model of circular polarization sensitivity based on a quarter-wave plate. These results demonstrate that C. gloriosa beetles respond differentially to circularly polarized light. In contrast, Chrysina woodi Horn 1885, a close relative with reduced circularly polarized reflection, exhibited no phototactic discrimination between linear and circularly polarized light. Circularly polarized sensitivity may allow C. gloriosa to perceive and communicate with conspecifics that remain cryptic to predators, reducing indirect costs of communication.Integrative Biolog
Antares completed: First selected results
In May 2008, the Antares collaboration has completed the construction of the
first deep sea neutrino telescope in the Northern hemisphere. Antares is a 3D
array of 900 photomultipliers held in the sea by twelve mooring lines anchored
at a depth of 2500 m in the Mediterranean Sea 40 km off the southern French
coast. The detection principle is based on the observation of Cerenkov light
induced by charged particles produced in neutrino interactions in the matter
surrounding the detector.Comment: conference proceedin
ANTARES and other Neutrino Telescopes in the Northern Hemisphere
Several projects are concentrating their efforts on opening the high energy
neutrino window on the Universe with km-scale detectors. The detection
principle relies on the observation, using photomultipliers, of the Cherenkov
light emitted by charged leptons induced by neutrino interactions in the
surrounding detector medium. In the Northern hemisphere, while the pioneering
Baikal telescope, has been operating for 10 years, most of the activity now
concentrates in the Mediterranean sea. Recently, the Antares collaboration has
completed the construction of a 12 line array comprising ~ 900
photomultipliers. In this paper we will review the main results achieved with
the detectors currently in operation in the Northern hemisphere, as well as the
R&D efforts towards the construction of a large volume neutrino telescope in
the Mediterranean.Comment: To Appear in proceedings of the XV International Symposium on Very
High Energy Cosmic Ray Interactions (ISVHECRI 2008
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