Between 60 and 70 million people in the United States are affected by gastrointestinal disorders. Many of these conditions are difficult to assess without surgical intervention and accurate noninvasive techniques to aid in clinical assessment are needed. Through the use of a superconducting quantum interference device (SQUID) gradiometer, the weak magnetic field generated as a result of muscula...

Auditory electric and magnetic P50(m), N1(m) and MMN(m) responses to standard, deviant and novel sounds were studied by recording brain electrical activity with 25 EEG electrodes simultaneously with the corresponding magnetic signals measured with 122 MEG gradiometer coils. The sources of these responses were located on the basis of the MEG responses; all were found to be in the supratemporal p...

We present here the current status of our high-sensitivity gravitygradiometer based on atom interferometry. In our apparatus, two clouds of laser-cooled rubidium atoms are launched in a fountain configuration and simultaneously interrogated by a Raman-pulse interferometry sequence. The system has recently been upgraded and its stability re-evaluated. We also discuss the recent progress of the e...

A low-noise and compact SQUID-NDE system cooled by a cryocooler has been developed for practical NDE of carbon-fiber composites. In order to suppress the magnetic noise due to a cryocooler, a planar high-Tc SQUID gradiometer, coaxial pulse tube cryocooler, and SQUID stage separated from the cold head of the cryocooler were introduced. There was no increase of magnetic flux noise due to the cryo...

Frequency-domain expressions are found for gradiometer and satellite-to-satellite tracking measurements of a point source on the surface Earth. The maximum signal-to-noise ratio as function noise in measurement apparatus is computed, from that minimum detectable mass inferred. A magnitude M3=100Gt gives 3 when GOCE-like passes directly over mass. On mission GRACE-FO M3=1.3Gt microwave instrumen...

We have been investigating the feasibility of radio-frequency RF, low-noise superconducting quantum interference device (SQUID) magnetometers and gradiometers operating in liquid nitrogen at 77 K. Using flux-focusing structures fabricated from epitaxial YBa2Cu3O7-chi films, we have attained a magnetic field resolution for a magnetometer of better than 200 fT Hz-1/2 at less than 1 Hz, i.e. over ...

A method for automatic 3D model generation derived from airborne gravity gradient data was illustrated. The proposed method computed a volumetric distribution of curvatures that form a 3D image of possible density distributions. The method relies on spectral analysis and the equivalence of the power spectra of the classical mean and differential curvatures of equipotential surfaces to create ps...

In the course of the satellite mission GOCE (Gravity field and steady-state Ocean Circulation Explorer), dedicated for the exploitation of the Earth's gravity field, with a planned launch in summer 2006, the data processing will be a huge numerical and computational intensive task. In this paper we will describe a direct approach developed and implemented in Graz for the derivation of a model f...