Special treatment reduces helium permeation of glass in vacuum systems

Internal surfaces of the glass component of a vacuum system are exposed to cesium in gaseous form to reduce helium permeation. The cesium gas is derived from decomposition of cesium nitrate through heating. Several minutes of exposure of the internal surfaces of the glass vessel are sufficient to complete the treatment

Development of UHF measurements

Collector gauge and orbitron gauge for ultrahigh vacuum measurement

Extreme vacuum technology including cryosorption, diffusion pump and pressure calibration studies Summary technical report, 1 Feb. 1965 - 1 Mar. 1966

Cryosorption, diffusion pump, and pressure calibration studies in extreme vacuum science and technology application progra

Extreme vacuum technology including cryosorption, diffusion pump and pressure calibration studies Quarterly status report no. 8, 1 May - 1 Aug. 1965

Cryosorption, diffusion pump, and low pressure calibration studies on Penning gauge and cold cathode magnetro

Study of low pressure application of the orbitron

Evaluation of low pressure performance of orbitron ionization gaug

An improved Orbitron ionization gage measures ultrahigh vacuum

Ionization gage with improved signal-to-noise ratio has a helical coil electrode which separates the solid cathode ion collector from the volume where ionization of gas molecules takes place. Helical coil increases lifetime of electrons and reduces secondary emission from the collector

Extreme vacuum technology developments

Ultrahigh vacuum environments technology development

From Feynman Proof of Maxwell Equations to Noncommutative Quantum Mechanics

In 1990, Dyson published a proof due to Feynman of the Maxwell equations assuming only the commutation relations between position and velocity. With this minimal assumption, Feynman never supposed the existence of Hamiltonian or Lagrangian formalism. In the present communication, we review the study of a relativistic particle using ``Feynman brackets.'' We show that Poincar\'e's magnetic angular momentum and Dirac magnetic monopole are the consequences of the structure of the Lorentz Lie algebra defined by the Feynman's brackets. Then, we extend these ideas to the dual momentum space by considering noncommutative quantum mechanics. In this context, we show that the noncommutativity of the coordinates is responsible for a new effect called the spin Hall effect. We also show its relation with the Berry phase notion. As a practical application, we found an unusual spin-orbit contribution of a nonrelativistic particle that could be experimentally tested. Another practical application is the Berry phase effect on the propagation of light in inhomogeneous media.Comment: Presented at the 3rd Feynman Festival (Collage Park, Maryland, U.S.A., August 2006

Extreme vacuum technology including cryopump, getter-ion pump, diffusion pump and pressure standardization studies Summary technical report, 16 Jun. 1966 - 16 Jun. 1967

Ultrahigh vacuum technology including cryopump, getter ion pump, diffusion pump, and pressure standardization studie

Appearance of Gauge Fields and Forces beyond the adiabatic approximation

We investigate the origin of quantum geometric phases, gauge fields and forces beyond the adiabatic regime. In particular, we extend the notions of geometric magnetic and electric forces discovered in studies of the Born-Oppenheimer approximation to arbitrary quantum systems described by matrix valued quantum Hamiltonians. The results are illustrated by several physical relevant examples