Now showing items 11-20 of 208
Digital techniques for real-time pulse shaping in radiation measurements
(Elsevier, 1994-12-30)
Recursive algorithms for real-time digital pulse shaping in pulse height measurements have been developed. The differentiated signal from the preamplifier (exponential pulse) is amplified and then digitized. Digital data ...
The electronic spectrum of fullerenes from the Dirac equation
(Elsevier, 1993-10-04)
The electronic spectrum of sheets of graphite (plane honeycomb lattice) folded into regular polyhedra is studied. A continuum limit valid for sufficiently large molecules and based on the tight-binding approximation is ...
Homo- and Heteronuclear Multiple-Quantum Filters for Measurement of NMR Isotope Shifts
(Elsevier, 1994-03)
The measurement of NMR isotope shifts as mechanistic probes can be complicated by mixtures of isotopomers. Homo- and heteronuclear NMR techniques based on multiple-quantum filtration are presented and shown to be a useful ...
High accuracy determination of the shape of the efficiency curve of the HPGe detector in the energy range 900 to 1300 keV
(Elsevier, 1994-12-30)
A method for high accuracy characterization of the shape of a High Purity Germanium (HPGe) detector efficiency curve has been developed. Radionuclides with decay schemes having at least two [gamma] lines, for which the ...
The effective potential and the renormalisation group
(Elsevier, 1993-04-26)
We discuss renormalisation-group improvement of the effective potential both in general and in the context of O(N) scalar [phi]4 and the Standard Model. In the latter case we find that absolute stability of the electroweak ...
Smooth massless limit of QED
(Elsevier, 1990-10-29)
Massless QED is studied by introducing different regularization schemes for the resulting mass singularities. It is demonstrated, for the one-loop corrections to electron scattering off an external potential, that cancellation ...
Granite, a new very high energy gamma-ray telescope
(Elsevier, 1990-03)
A international collaboration of astrophysicists plan to construct a new 10-meter diameter gamma-ray Cerenkov telescope at the Whipple Observatory on Mt. Hopkins in Arizona. By operatin in coincidence with the original ...
Gamma-ray spectral imaging using a single-shutter radiation camera
(Elsevier, 1990-12-20)
As part of a program to develop mobile robots for reactor environments, we are developing a radiation-imaging camera capable of operating in medium-intensity (Z scintillator. The raster-scanning camera uses a lead-shielded ...
Amplification of 1 ps pulses at 1.053 [mu]m in a Ti:Al2O3 regenerative amplifier
(Elsevier, 1991-07-01)
We demonstrate the operation of a Ti:Al2O3 regenerative amplifier tunable around 1 [mu]m. Gains up to 108 at 1.053 [mu]m without any spectral narrowing are obtained. This amplifier is designed for use in terawatt picosecond ...
Solenoid and sextupole optics of ultra-cold atomic hydrogen beams
(Elsevier, 1993-06-20)
Analytic calculations and particle tracking simulations are presented for a polarized atomic hydrogen beam produced by extraction from a superfluid helium coated cell in a large solenoidal magnetic field. Compression of ...