0000000000266386

AUTHOR

O. Neuvonen

showing 3 related works from this author

Prompt and delayed spectroscopy of 203At : Observation of a shears band and a 29/2+ isomeric state

2018

Using fusion-evaporation reactions, a gas-filled recoil separator, recoil-gating technique and recoil-isomer decay tagging technique we have extended the level scheme of 203 At ( N = 118 ) significantly. We have observed an isomeric [ τ = 14.1 ( 3 ) μ s ] state with a spin and parity of 29 / 2 + . The isomeric state is suggested to originate from the π ( h 9 / 2 ) ⊗ ∣ ∣ 202 Po ; 11 − ⟩ coupling, and it is depopulated through 286 keV E 2 and 366 keV E 3 transitions. In addition, we have observed a cascade of magnetic-dipole transitions which is suggested to be generated by the shears mechanism. peerReviewed

level densitiesnuclear spinelectromagnetic transitionsnuclear density functional theorytiheysfunktionaaliteoriaspektroskopialifetimeswidthsenergy levelsNuclear Experimentisomer decaysydinfysiikkanuclear parity
researchProduct

Experimental study of isomeric intruder 12+ states in At197,203

2017

A newly observed isomeric intruder ${\textonehalf{}}^{+}$ state $[{T}_{\textonehalf{}}=3.5(6)\phantom{\rule{0.16em}{0ex}}\mathrm{ms}]$ is identified in $^{203}\mathrm{At}$ using a gas-filled recoil separator and fusion-evaporation reactions. The isomer is depopulated through a cascade of $E3$ and mixed $M1/E2$ transitions to the ${9/2}^{\ensuremath{-}}$ ground state, and it is suggested to originate from the $\ensuremath{\pi}{({s}_{\textonehalf{}})}^{\ensuremath{-}1}$ configuration. In addition, the structures above the ${\textonehalf{}}^{+}$ state in $^{203}\mathrm{At}$ and $^{197}\mathrm{At}$ are studied using in-beam $\ensuremath{\gamma}$-ray spectroscopy, recoil-decay tagging, and recoi…

Physics010308 nuclear & particles physics0103 physical sciencesState (functional analysis)Atomic physics010306 general physicsSpectroscopyGround state01 natural sciencesRecoil separatorPhysical Review C
researchProduct

A time-of-flight correction procedure for fast-timing data of recoils with varying implantation positions at a spectrometer focal plane

2019

Abstract Fast-timing measurements at the focal plane of a separator can suffer from poor timing resolution. This is due to the variations in time-of-flight (ToF) for photons travelling to a given detector, which arise from the changes in the implantation positions of the recoil nuclei emitting the γ rays of interest. In order to minimise these effects on timing measurements, a procedure is presented that improves fast-timing data by performing ToF corrections on an event-by-event basis. This method was used to correct data collected with an array of eight LaBr 3 detectors, which detected γ rays from spatially distributed 138Gd recoil-implants at the focal plane of the Recoil-Ion-Transport-U…

Nuclear and High Energy PhysicsPhotonGeneralised-centroid-difference methodtutkimuslaitteetspektrometritStandard deviation138GdRecoilgeneralised-centroid-difference methodDistributed sourceNuclear ExperimentNuclear-state lifetimesInstrumentationdetectorsPhysicsnuclear-state lifetimesta114Spectrometerfast-timingDetectorCentroidFast-timingLaBr3Computational physicsTime of flightCardinal pointdistributed sourceydinfysiikkaNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
researchProduct