Method and means for helium/hydrogen ratio measurement by alpha scattering
US4194115A · kind A · utility
Inventors
Key dates
| Filing date | Nov 7, 1978 |
| Grant date | Mar 18, 1980 |
| Priority date | — |
| Expiry date | Nov 7, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N23/201
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus and method for determining helium to hydrogen ratios in a gaseous sample by measurement of forward scattering products due to alpha particle collisions with helium and hydrogen contained within the gaseous sample. More specifically, an apparatus is disclosed in which a gaseous sample, contained within an enclosure, is bombarded by alpha particles created by a self contained radioactive source. Baffles are positioned in the enclosure so that only scattering products falling within a predetermined forward scattering angular range can impact a detector assembly. In an embodiment scattered particles are detected by two detectors mounted in tandem, the first completely blocking the second detector with respect to incident scattering products. This embodiment is based on the principle that scattering products have a forward scattering angle .theta. greater than 15 degrees due to alpha particle/hydrogen collisions comprise only recoil protons. For a given kinetic energy, recoil protons will penetrate farther into silicon detector material than will scattering products from alpha particle/helium collisions. Thus, an apparatus according to the teachings of the invention identifies…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.