A resistive-anode based position-sensitive Rydberg atom detector.

We describe here the development and characterization of a position-sensitive detector for Rydberg atom experiments. The detector builds on an earlier design that field-ionized incident Rydberg positronium (Ps) atoms and then electrostatically focused the freed positrons onto a micro-channel plate (MCP) detector without the use of a position sensitive anode. In this design, pulses from the MCP are deposited onto a resistive anode, providing a means of measuring the incident particles' x, y positions.

Focusing of a Rydberg Positronium Beam with an Ellipsoidal Electrostatic Mirror.

Slow atoms in Rydberg states can exhibit specular reflection from a cylindrical surface upon which an azimuthally periodic potential is imposed. We have constructed a concave mirror of this type, in the shape of a truncated oblate ellipsoid of revolution, which has a focal length of (1.50±0.

Microfabricated quadrupole ion trap for mass spectrometer applications.

An array of miniaturized cylindrical quadrupole ion traps, with a radius of 20 microm, is fabricated using silicon micromachining using phosphorus doped polysilicon and silicon dioxide for the purpose of creating a mass spectrometer on a chip. We have operated the array for mass-selective ion ejection and mass analysis using Xe ions at a pressure of 10(-4). The scaling rules for the ion trap in relation to operating pressure, voltage, and frequency are examined.

Analysis of volatile organic compounds in air with a micro ion trap mass analyzer.

Analysis of several volatile organic compounds in air has been demonstrated with a micro ion trap mass analyzer equipped with a semipermeable membrane sampling inlet. MS/MS of selected compounds was also shown to be feasible with the miniature ion trap and could be used to improve sensitivity by reducing background noise.