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We present results for levels in 26Si (the mirror of nucleus 26Si). The calculated gamma decay lifetimes and 25Al to 26Si spectroscopic factors together with experimental information on the levels of excited states will be used to determine the Al 25 ( p , γ ) Si 26 reaction rates together with a theoretical error on this rate based on the use of the USDA and USDB interactions.

The Nuclear Structure Laboratory (NSL) at the University of Notre Dame installed its Browne–Buechner spectrograph in the early 1970s for highly accurate energy measurements of nuclear reactions. Current renovation and upgrading of this spectrograph will enable operation of the magnet in a gas-filled mode, in particular for the study of nuclear reactions with low cross-sections of interest in nuclear astrophysics. One of the principle issues shared by measurements of extremely low abundances in Accelerator Mass Spectrometry (AMS) and nuclear astrophysics is the discrimination between the nuclei of interest and often very intense isobaric background. Recently the AMS technique of the gas-filled magnet has very successfully been used at Argonne National Laboratory (ANL) to overcome this in the study of both environmental noble gas traces ( 39 Ar) and the measurement of cross-sections of interest in stellar nucleosynthesis i.e. the 62 Ni( n , γ) 63 Ni reaction. We hope to extend these techniques further to the observations of astrophysically important reactions such as 40 Ca(α, γ) 44 Ti and 78 Kr(α, γ) 82 Sr.

A complete treatment of the thermal noise in a MOSFET including both drain current noise and induced gate current noise has been developed by deriving a small-signal model valid at high frequencies and for short-channel devices. On the basis of this model the parameters currently used for the representation of a noisy two-port have been derived. As those parameters depend on the noise sources and on the admittance matrix terms, both these contributions have been accurately modeled. Finally, the model has been applied to the derivation of MOSFET two-port noise parameters in order to minimize noise figure of low noise amplifiers.