The perspective to build large accelerators based on high gradient superconducting cavities posed a number of new problems that have been mainly addressed in the preparation of the TESLA project. In this paper I briefly discuss the TESLA Collaboration contributions to the state of the art of the SRF technology and how they have been at the basis of the cold choice for the International Linear C...

4 Observational studies suggest that the stratospheric quasi-biennial oscillation (QBO) can 5 modulate tropical deep convection. We use a cloud-resolving model with a limited domain, 6 representing a convective column in the tropics, to study the mechanisms of this modulation. 7 The large-scale circulation is parameterized using the weak temperature gradient (WTG) 8 approximation, under which t...

Mitigate B1+ inhomogeneity by the combination of RF shimming and B1+ remapping using nonlinear gradient coils Yi-Cheng Hsu, Ying-Hua Chu, Riccardo Lattanzi, Daniel K Sodickson, and Fa-Hsuan Lin Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan, The Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medic...

Previously we introduced the Uniform Cram&-Rao (CR) Bound as a lower bound on the variance of biased estimators, along with the concept of the delta-sigma tradeoff curve. For an estimator whose variance lies on this curve, lower variance can only be achieved at the price of increased estimator bias gradient norm, and vice versa. However, for single pixel estimation, one can specify a variety of...

Introduction Arterial spin labeling is sensitive to contamination due to off-resonance effects of the RF label. While it has been argued that in PASL these effects are small compared to pulse profile effects [1], this assessment has to be re-evaluated in view of the advent of highly selective gradient-modulated adiabatic pulses such as FOCI [2], requiring several times more RF energy than the c...

The Compact Linear Collider study (CLIC) is in the process of completing a Conceptual Design Report for a multi-TeV linear electron-positron collider. The CLIC-concept is based on high gradient normal-conducting accelerating structures. The RF power for the acceleration of the colliding beams is produced by a novel two beam acceleration scheme, where power is extracted from a high current drive...

equilibrium geometry, electronic structures, and vibrational modes of cob8- were investigated in the pbepbe/6-311+g(d,p) level of theory. the nucleus independent chemical shift (nics) analysis and magnetizability values were used for studying of aromaticity in cob8-. the effects of different solvents on the structure and frontier orbital energies were calculated using the polarizable continuum ...

In the early 1990s, the traditional framework of NMR spectroscopy was challenged through a series of simple experiments. The pulse sequences used consisted of a few RF pulses and a few gradient pulses, and the samples were mixtures of simple molecules. The spectra showed unexpected cross peaks between spins in different molecules. ( ) In order to explain these results, two basic assumptions had...

The authors describe a method for the basic and RF field inhomogeneity estimation in NMR based on the measurement of T2 and T2*. The method combines the gradient and spin echo acquisition techniques to differentiate the T2 and T2* relaxation times. Exponential approximation of the relaxation process has to be performed. Experimental results for the plastic and copper specimens are shown.

Statement of the problem or situation that is being addressed typically, one to three sentences. New developments in the design of fixed-field alternating gradient (FFAG) synchrotrons have sparked interest in their use as rapid-cycling, high intensity accelerators of ions, protons, muons, and electrons. Compact RF cavities that tune rapidly over various frequency ranges are needed to provide th...