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A Nion spherical-aberration (Cs) corrector was recently installed on Lehigh University's 300-keV cold field-emission gun (FEG) Vacuum Generators HB 603 dedicated scanning transmission electron microscope (STEM), optimized for X-ray analysis of thin specimens. In this article, the impact of the Cs-corrector on X-ray analysis is theoretically evaluated, in(More)
A series of supported 1-60% TiO(2)/SiO(2) catalysts were synthesized and subsequently used to anchor surface VO(x) redox and surface WO(x) acid sites. The supported TiO(x), VO(x), and WO(x) phases were physically characterized with TEM, in situ Raman and UV-vis spectroscopy, and chemically probed with in situ CH(3)OH-IR, CH(3)OH-TPSR and steady-state(More)
We have created a general methodology for calculating the wavelength-dependent light curves of close-in extrasolar giant planets (EGPs) as they traverse their orbits. Focussing on the transiting EGPs HD189733b, TrES-1, and HD209458b, we calculate planet/star flux ratios during secondary eclipse and compare them with the Spitzer data points obtained so far(More)
We find that a theoretical fit to all the HD 209458b data at secondary eclipse requires that the dayside atmosphere of HD 209458b have a thermal inversion and a stratosphere. This inversion is caused by the capture of optical stellar flux by an absorber of uncertain origin that resides at altitude. One consequence of stratospheric heating and temperature(More)
We report on the measurement of the 7.5–14.7 mm spectrum for the transiting extrasolar giant planet HD 189733b using the Infrared Spectrograph on the Spitzer Space Telescope. Although the observations comprise only 12 hr of telescope time, the continuum is well measured and has a flux ranging from 0.6 to 1.8 mJy over the wavelength range, or of the flux of(More)
In this paper, we present a new mechanism for core-collapse supernova explosions that relies upon acoustic power generated in the inner core as the driver. In our simulation using an 11-M ⊙ progenitor, an advective-acoustic oscillationà la Foglizzo with a period of ∼25−30 milliseconds (ms) arises ∼200 ms after bounce. Its growth saturates due to the(More)
We construct a new model of the atmosphere of the transiting extrasolar giant planet HD 209458b to investigate the disparity between the observed strength of the sodium absorption feature at 589 nm and the predictions of previous models. Using a sodium ionization model that includes photoionization by stellar UV flux and radiative recombination, we show(More)