When an electron is born through ionization in a strong laser field, the wavepacket can be very large. As this large wavepacket continues to experience the laser field, different parts of the packet are accelerated in different directions. How will such a system radiate light? Contradicting predictions have been published in the literature, and Professors Justin Peatross and Michael Ware are looking to solve the issue with theory and experiment.
This image was secured during the installation of the 0.9-m telescope at the BYU West Mountain Observatory. Data for this image is from August 27, 2009. This was the first night that a CCD had been mounted on the telescope so that imaging was possible. This 'First Light' image shows the globular cluster known as M15 in the constellation of Pegasus. The distance to this cluster is more than 33,000 light years and yet individual stars are easily resolved all through the cluster. Globular cluster stars have an extremely low abundance of heavy elements as compared to stars found in the solar neighborhood and represent the oldest population of stars known in the Galaxy. It is interesting to note the many cool red giant stars that are visible in the cluster as well as a large number of evolved horizontal branch stars that are blue in color. Many of the horizontal branch stars are known to be RR Lyrae variable stars that are useful as distance indicators since it is possible to determine their luminosity and compare that value to their apparent magnitude as measured from the observed images. The color image processing for this picture is the work of renowned image processing guru, Dr. Rob Gendler.
Elora Salway used point spread modelling to determine the magnitudes of the primary and secondary component of very close binary brown dwarf systems observed by the Hubble Space Telescope. These magnitudes will be used to constrain theoretical models that allow us to estimate the temperature, gravity, and cloud structure of these brown dwarfs and will help us better understand and characterize the formation of low mass stars and brown dwarfs. Her results were recently presented at the January 2015 meeting of the American Astronomical Society.
Wave-like modulations with non-lattice periodicities accompany a variety of important physical phenomena (e.g. magnetism and superconductivity) and dramatically complicate any quantitative crystal-structure analysis. An exhaustive group-theoretical enumeration of the order parameters that can arise from 1D incommensurate modulations now make it much easier to characterize crystals that behave this way. Figure: Short-range modulation in La1.8Sr2.2Mn2O7.
Not astronomy! This is actually single-crystal diffuse x-ray scattering from an important industrial isomerization catalyst called mordenite, where the L = 0 plane of reciprocal space was reconstructed using portions from over 1000 CCD X-ray camera images. The broad patches, open diamonds, and star-shaped distributions are clues that reveal a complex architecture of framework defects with implications for this zeolite’s unusual adsorptive and catalytic properties.
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Hao Wang, Kevin Laughlin, Jake Bagley, Barry Lunt, Robert Davis, and Matthew Linford recently published an article titled "XPS and ToF-SIMS Analysis of the Information Storage Medium of a Permanent Write-Once-Read-Many (WORM) Archival, Solid State Data Storage Device" in International Symposium on Optical Memory (ISOM), (Hsinchu, Taiwan, October 2014). . Click on the image above to read it.
Rainbows and Rays over Bryce Canyon : What's happening over Bryce Canyon? Two different optical effects that were captured in one image taken earlier this month. Both effects needed to have the Sun situated directly behind the photographer....
This photograph and Description come from NASA's Astronomy Picture of the Day web site.