A5077850065- Nuclear physics research studies
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Radioactive contamination and transfer
- Radioactivity and Radon Measurements
- Radiation Dose and Imaging
- Nuclear and radioactivity studies
- Advanced Chemical Physics Studies
- Astronomical and nuclear sciences
- Quantum Chromodynamics and Particle Interactions
- Graphite, nuclear technology, radiation studies
- Quantum, superfluid, helium dynamics
- Nuclear reactor physics and engineering
- Advanced NMR Techniques and Applications
- Radioactive Decay and Measurement Techniques
- Radiopharmaceutical Chemistry and Applications
- Risk and Safety Analysis
- Nuclear Issues and Defense
- Radiation Therapy and Dosimetry
- Rare-earth and actinide compounds
- Atomic and Subatomic Physics Research
- Astro and Planetary Science
- Particle physics theoretical and experimental studies
- Risk Perception and Management
- Radiation Detection and Scintillator Technologies
Radiation and Nuclear Safety Authority
2009-2024
Norwegian Radiation and Nuclear Safety Authority
2010
University of Jyväskylä
1998-2009
University of York
2005
Daresbury Laboratory
1998-2003
University of Liverpool
1998-2002
Centre National de la Recherche Scientifique
1999-2001
University of Surrey
1997-2001
Institut National de Physique Nucléaire et de Physique des Particules
1999-2001
University of Brighton
2001
The gas-filled recoil separator RITU, combined with Ge detector arrays at the Department of Physics, University Jyväskylä (JYFL), Finland, has successfully been employed in recoil-decay-tagging (RDT) experiments for probing structures several very neutron-deficient heavy nuclei first time. In this paper new data Hg, Pb and Po are summarized discussed. These shed light on behaviour role proton multiparticle-multihole intruder states 82<N<126 mid-shell beyond.
An in-beam study of excited states in the transfermium nucleus 252No has been performed using recoil separator RITU together with JUROSPHERE II array at University Jyväskylä. This is second studied an experiment. Levels up to spin 20 were populated and compared levels 254No. upbend seen a frequency 200 keV/ħ corresponding 16. We also use improved systematics connect energy lowest 2+ state its half-life find that deformation both 252,254No slightly larger than previously assumed.Received July...
We report on a set of in-beam studies excited states in $^{250}\mathrm{Fm}$. detected prompt \ensuremath{\gamma} rays by using the JUROSPHERE IV array and conversion electrons SACRED spectrometer. Both devices were used conjunction with RITU gas-filled recoil separator located at University Jyv\"askyl\"a. $^{250}\mathrm{Fm}$ nuclei produced through $^{204}\mathrm{Hg}$($^{48}\mathrm{Ca}$,$2n)$$^{250}\mathrm{Fm}$ fusion-evaporation reaction. An experimental excitation function gave maximum...
The spectrum of prompt conversion electrons emitted by excited 254No nuclei has been measured, revealing discrete lines arising from transitions within the ground state band. A striking feature is a broad distribution that peaks near 100 keV and comprises high multiplicity electron cascades, probably originating M1 rotational bands built on K states.
To predict uranium in human hair due to chronic exposure through drinking water, a compartment representing was added into the biokinetic model developed by International Commission on Radiological Protection (ICRP). The compartmental used excretion as bioassay indicator elevated intakes. Two pathways, one starting from of plasma and other intermediate turnover soft tissue, are assumed transfer hair. rate determined reported contents urine hair, taking account growth 0.1 g d(-1). fractional...
Uranium concentrations in the household water, urine, and hair of occupationally unexposed Finnish working population were determined using inductively coupled plasma mass spectrometry (ICP-MS). The age randomly selected participants ranged from 18 to 66 y. mean uranium 1.25 μg L−1, 0.016 0.216 g−1, respectively. concentration was 3- 15-fold higher than values reported literature, while urine similar those measured elsewhere Europe. observed large variation can be explained by drinking...
Excited states in the light lead nucleus, ${}^{182}\mathrm{Pb},$ have been observed for first time, by means of recoil-decay tagging technique. A rotational band has which features common with bands attributed to a prolate configuration heavier neutron deficient nuclei, ${}^{184\ensuremath{-}188}\mathrm{Pb}.$ variable moment inertia fit this suggests that minimum risen significantly energy compared next even ${}^{184}\mathrm{Pb}.$ This constitutes firm evidence minimization respect spherical...
The nuclei ${}^{55,56}\mathrm{Cr}$ were populated to high spin following the reaction ${}^{48}\mathrm{Ca}{(}^{11}\mathrm{B}{,pxn)}^{58\ensuremath{-}x}\mathrm{Cr}$ at a beam energy of 35--40 MeV. level scheme ${}^{55}\mathrm{Cr}$ has been confirmed and extended ${J}^{\ensuremath{\pi}}={\frac{25}{2}}^{+}.$ ${}^{56}\mathrm{Cr}$ $J=13.$ spins parity majority levels have determined unambiguously for first time. firm evidence an intruder band based on $\ensuremath{\nu}{g}_{9/2}$ orbital observed...
The new neutron deficient nuclide ${}^{195}\mathrm{Rn}$ and the ${}^{196}\mathrm{Rn}$ have been produced in fusion evaporation reactions using ${}^{56}\mathrm{Fe}$ ions on ${}^{142}\mathrm{Nd}$ targets. A gas-filled recoil separator was used to separate products from scattered beam. activities were implanted a position sensitive silicon detector. isotopes identified spatial time correlations between implants decays. Two $\ensuremath{\alpha}$ decaying isomeric states, with...
Low-lying proton-based intruder states have been observed in the odd-mass isotopes ${}^{189,191,193}\mathrm{Pb}$ experiments at RITU gas-filled recoil separator. The identification has performed by observing fine structure $\ensuremath{\alpha}$ decay of parent ${}^{193,195,197}\mathrm{Po}$ nuclei prompt coincidence with conversion electrons and $\ensuremath{\gamma}$ rays daughter lead isotopes. Along literature data these results establish a systematics from ${}^{197}\mathrm{Pb}$ down to...
Excited states in (216)Th were investigated via prompt and delayed gamma decays the recoil-decay tagging method. The decay schemes of I(pi) = (8+), t(1/2) 128(8) micros, (11-), 615(55) ns, (14+), > or 130 ns isomers established. configuration pi h(9/2)f(7/2) is assigned to (8+) isomer, which implies that h(9/2) f(7/2) are nearly degenerate. This ascribed increased binding orbital by its coupling a low-lying (3-) state at E(x) 1687 keV. role octupole pairing correlations for Z 92 shell...
The transitional nuclei ${}_{ 42}^{100}\mathrm{Mo}$, 44}^{104}\mathrm{Ru}$, and 46}^{108}\mathrm{Pd}$ have been studied as products of binary reactions formed by a ${}_{36}^{86}$Kr beam impinging on 46}^{110}\mathrm{Pd}$ target. yrast states are observed above the region first backbend. In each case this backbend is associated with breaking neutron ${(h}_{11/2}{)}^{2}$ pair. results consistent predictions cranked shell model calculations systematics neighboring nuclei.
Prompt $\ensuremath{\gamma}$ rays have been observed for the first time from neutron-deficient nucleus ${}^{191}\mathrm{Po}$ using recoil-decay tagging technique at RITU gas-filled separator. In addition improved $\ensuremath{\alpha}$ decay data measured and its daughter product ${}^{187}\mathrm{Pb}.$ The complementary $\ensuremath{\gamma}$- $\ensuremath{\alpha}$-decay point to onset of oblate deformation in light odd-mass Po nuclei by approaching neutron midshell $N=104.$ pattern favored...
Prompt and delayed $\ensuremath{\gamma}$ rays from $^{191,193}\mathrm{Bi}$ have been identified using the recoil-decay tagging, isomer recoil gating techniques, resulting in extensive level schemes for both nuclei. Excitation energies of isomeric $13∕{2}^{+}$ states established oblate strongly coupled bands built on them observed. The nearly spherical $9∕{2}^{\ensuremath{-}}$ ground-state appear to be crossed by more oblate-deformed low-lying structures. properties feeding $1∕{2}^{+}$...
A ${K}^{\ensuremath{\pi}}{=8}^{\ensuremath{-}}$ collective rotational band has been established upon the 6 $\ensuremath{\mu}$s isomeric state in very neutron-deficient nucleus ${}^{138}\mathrm{Gd}.$ The was observed using a technique involving correlation of $\ensuremath{\gamma}$-ray transitions across state. single-particle configuration isomer deduced from $\ensuremath{\Delta}I=2$ to $\ensuremath{\Delta}I=1$ intensity branching ratios. In addition, series other were which are reasoned be...
\ensuremath{\gamma} rays following the $^{160}\mathrm{Dy}$${(}^{36}$Ar,4n${)}^{192}$Po reaction have been identified by employing a high-transmission gas-filled separator in recoil decay tagging measurements. The deduced level scheme reveals flattening of energy systematics, when going towards neutron midshell indicating that deformed intruder structures become yrast. \textcopyright{} 1996 American Physical Society.