Abstract:
ASYMMETRICALINTERACTIONSOF22NaPOSITRONSWITHD┐,L┐PHENYLALANINESWangWenqingDingXiangLinFeng(DepartmentofTechnicalPhysics,PekingUniversity,Beijing100871)WangYunyuCaoHuimin(InstituteofHighEnergyPhysics,ChineseAcademyofSciences,Beijing100039)ABSTRACTTheaimofthisworkliesinsearchingtherelationbetweenasymmetryofD-,L-pheny-lalaninesandpositroniumformation.ThepurityofthesublimedD-,L-phenylalaninesischeckedbyFT-IR.TherelativequantumeficiencyissamefortheD-,L-isomers.Thesam-plesarepressedcarefulytotabletsof13.0mmdiameterand2.0mmthicknesswiththesamerigorouspressure.Foreachsample,thelifetimespectrumismeasuredfor8times.Thespectraaredecomposedtothreecomponents.Thelongestoneatributedtopositroniumoftripletstate(o-Ps).Theexperimentalresultsshowthatboththeτ3andI3areabithigherinD-isomerthaninL-isomer.Theτ3are(1.570±0.033)nsand(1.529±0.033)nsinD-,L-phenylalaninesrespectively,andtheI3are(10.107±0.315)%and(8.457±0.379)%.Itmeansthatthepositronsseemtoformmorepositroniums(o-Ps)inD-PhethaninL-PhebyaI3,d/I3,Lfactorof1.195.KeywordsPositronannihilation22NaD-,L-PhenylalanineAsymmetricalinter-action