6533b86ffe1ef96bd12ce86e
RESEARCH PRODUCT
Doppler-broadening of gamma rays following muon capture: search for scalar coupling
V.b. BrudaninT. FilipovaTeemu SiiskonenYu. ShitovJouni SuhonenC. PetitjeanRené PrieelsV. WiauxI. YutlandovSh. ZaparovV. EgorovTs. VylovCh. BriançonJules Deutschsubject
Nuclear reactionPhysicsNuclear and High Energy PhysicsMuonCorrelation coefficient[PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex]010308 nuclear & particles physicsGamma ray[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]Impulse (physics)01 natural sciencesMuon captureNuclear physicsPseudoscalar0103 physical sciences010306 general physicsDoppler broadeningdescription
Abstract A precision measurement of the 277 keV γ ray produced by capturing muons in gaseous oxygen was performed using high-resolution HPGe detectors. The Doppler-broadened shape of this line is sensitive to the possible admixture into muon capture of genuine scalar interaction. This experiment complements, in the muon sector, in principle, similar ones undertaken recently in nuclear β decay. Using a procedure discussed in earlier papers, a fit to the experimental line-shape allowed us to obtain for the recoil–gamma correlation coefficient the value of a 1 2 =0.096±0.041 (95% CL). The available evaluations of the contributing nuclear matrix elements, performed in the impulse approximation in the absence of scalar interaction, produce correlation coefficients in disagreement with our result. These evaluations are independent of the induced pseudoscalar coupling and so of the validity of the PCAC hypothesis, but their reliability and model dependence remain to be investigated.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2002-03-01 | Nuclear Physics A |