Positron lifetime measurements in chiral nematic liquid crystals

Technical Report · Tue Oct 01 04:00:00 EDT 1991

OSTI ID:5974715

Singh, J J; Eftekhari, A; Parmar, D S

Positron lifetimes in the isotropic phases of chiral nematic liquid crystal formulations and their mixtures up to the racemic level were measured. The lifetime spectra for all liquid crystal systems were analyzed into three components. Although the individual spectra in the left- and right-handed components are identical, their racemic mixtures exhibit much larger orthopositronium lifetimes; these larger lifetimes indicate the presence of larger microvoids. This result is consistent with the reportedly higher thermodynamic stability and color play range in the racemic mixtures of chiral nematic liquid crystals.

• Research Organization: National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center
• OSTI ID: 5974715
• Report Number(s): N-92-10677; NASA-TP--3122; L--16948; NAS--1.60:3122
• Country of Publication: United States
• Language: English

Related Subjects

662310* -- Weak & Electromagnetic Interactions of Leptons-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
CHIRALITY
CRYSTALS
DATA
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
FERMIONS
FLUIDS
INFORMATION
LEPTON REACTIONS
LEPTONS
LIFETIME
LIQUID CRYSTALS
LIQUIDS
MATTER
NUCLEAR REACTIONS
NUMERICAL DATA
PARTICLE PROPERTIES
POSITRON REACTIONS
POSITRONS