Imaging techniques should differentiate between specific signals, from the biomolecules of interest, and non-specific signals, from the background. We present a probe containing (15)N and (14)N isotopes in approximately equal proportion, for secondary ion mass spectrometry imaging. This probe designed for a precise biomolecule analysis is insensitive to background signals.

A direct, ambient ionization method has been developed for the determination of creatinine in urine that combines derivatization and thermal desorption with extractive electrospray ionization and ion mobility-mass spectrometry. The volatility of creatinine was enhanced by a rapid on-probe aqueous acylation reaction, using a custom-made thermal desorption probe, allowing thermal desorption and i...

New method for the calibration of three-dimensional atom-probe mass spectra Energy distribution and spatial structure of electrosprays of ionic liquids in vacuo Recent results with Au ions from a multiampere electron beam ion source at Brookhaven National Laboratory (invited abstract) Time-of-flight secondary ion mass spectroscopy for surface analysis of insulators using a cluster ion beam Quan...

Material and device characterization is challenged by continuously decreasing device dimensions placing significant demands on characterization instruments and measurement interpretation. The trend in many techniques is clearly toward characterization of smaller dimensions. Among the myriad of characterization techniques in use today, I discuss recent advances in probe microscopy, interferometr...

Recent analyses of ion measurements band electrostatic noise observed in the frequency obtained from the Differential Ion Flux Probe range of 30 Hz to 178 kHz [Shawhan et al., 1984]. (DIFP) on the deployed Plasma Diagnostics Package The Differential Ion Flux Probe (DIFP), used (PDP) during the OSS-1/STS-3 mission have provided for the ion measurements, has been described in an additional insigh...

Current density profiles in the beam of a xenon ion engine are measured using a long tungsten wire probe to collect ions while making radial traverses through the beam. Between traverses the probe is moved along the axial coordinate to sample the profile at distances of 5-50 cm from the exit plane. Abel inversion of the data provides flux contour maps and integrated current maps as functions of...

We investigate the interaction of a laser-cooled trapped ion (Ba+ or Rb+) with an optically confined ⁸⁷Rb Bose-Einstein condensate. The system features interesting dynamics of the ion and the atom cloud as determined by their collisions and their motion in their respective traps. Elastic as well as inelastic processes are observed and their respective cross sections are determined. We demonstra...

Electron transfer in collisions between Rydberg atoms and targets that attach free low-energy electrons can lead to the formation of heavy-Rydberg ion-pair states comprising a positive-negative ion pair that orbit each other at large separations weakly bound by their mutual electrostatic attraction. It is shown that measurements of the velocity distribution of the ion-pair states produced in su...

The resolution of helium ion scanning microscopes working in the secondary electron emission mode is theoretically estimated in the energy interval of E = 0.3-100 keV. The corresponding probe diameter improves with energy from 1.0 to 0.2 nm. A theoretical probe diameter of 0.25 nm can be obtained by use of a standard three-electrode objective lens of electrostatic microscopes. The most importan...