Search results for "Rome"
showing 10 items of 12914 documents
Recent experiments at the JYFLTRAP Penning trap
2020
AbstractThe JYFLTRAP double Penning trap mass spectrometer at the Ion Guide Isotope Separator On-Line (IGISOL) facility offers excellent possibilities for high-precision mass measurements of radioactive ions. Around 400 atomic masses, including around 50 isomeric states, have been measured since JYFLTRAP became operational. JYFLTRAP has also been used as a high-resolution mass separator for decay spectroscopy experiments as well as an ion counter for fission yield studies. In this contribution, an overview of recent activities at the JYFLTRAP Penning trap is given, with a focus on nuclei discussed in the PLATAN2019 meeting.
α-decay spectroscopy of the N = 130 isotones 218Ra and 220Th: Mitigation of α-particle energy summing with implanted nuclei
2019
An analysis technique has been developed in order to mitigate energy summing due to sequential short-lived α decays from nuclei implanted into a silicon detector. Using this technique, α-decay spectroscopy of the N=130 isotones 218Ra (Z=88) and 220Th (Z=90) has been performed. The energies of the α particles emitted in the 218Ra→214Rn and 220Th→216Ra ground-state-to-ground-state decays have been measured to be 8381(4) keV and 8818(13) keV, respectively. The half-lives of the ground states of 218Ra and 220Th have been measured to be 25.99(10) μs and 10.4(4) μs, respectively. The half-lives of the ground states of the α-decay daughters, 214Rn and 216Ra, have been measured to be 259(3) ns and …
Studying Gamow-Teller transitions and the assignment of isomeric and ground states at $N=50$
2022
Direct mass measurements of neutron-deficient nuclides around the N=50 shell closure below $^{100}$Sn were performed at the FRS Ion Catcher (FRS-IC) at GSI, Germany. The nuclei were produced by projectile fragmentation of $^{124}$Xe, separated in the fragment separator FRS and delivered to the FRS-IC. The masses of 14 ground states and two isomers were measured with relative mass uncertainties down to 1×10−7 using the multiple-reflection time-of-flight mass spectrometer of the FRS-IC, including the first direct mass measurements of $^{98}$Cd and $^{97}$Rh. A new QEC=5437±67 keV was obtained for $^{98}$Cd, resulting in a summed Gamow-Teller (GT) strength for the five observed transitions (0+…
Determination of β-decay ground state feeding of nuclei of importance for reactor applications
2020
In β-decay studies the determination of the decay probability to the ground state (g.s.) of the daughter nucleus often suffers from large systematic errors. The difficulty of the measurement is related to the absence of associated delayed γ-ray emission. In this work we revisit the 4πγ−β method proposed by Greenwood and collaborators in the 1990s, which has the potential to overcome some of the experimental difficulties. Our interest is driven by the need to determine accurately the β-intensity distributions of fission products that contribute significantly to the reactor decay heat and to the antineutrinos emitted by reactors. A number of such decays have large g.s. branches. The method is…
Penning-trap mass measurements on 92, 94-98, 100Mo with JYFLTRAP
2012
Penning-trap measurements on stable 92, 94-98, 100Mo isotopes have been performed with relative accuracy of \ensuremath1⋅10−8\ensuremath1⋅10−8 with the JYFLTRAP Penning-trap mass spectrometer by using 85Rb as a reference. The Mo isotopes have been found to be about 3keV more bound than given in the Atomic Mass Evaluation 2003 (AME03). The results confirm that the discrepancy between the ISOLTRAP and JYFLTRAP data for 101-105Cd isotopes was due to an erroneous value in the AME03 for 96Mo used as a reference at JYFLTRAP. The measured frequency ratios of Mo isotopes have been used to update mass-excess values of 30 neutron-deficient nuclides measured at JYFLTRAP. peerReviewed
Mass measurements of neutron-deficient nuclei and their implications for astrophysics
2012
During the years 2005-2010 the double-Penning-trap mass spectrometer JYFLTRAP has been used to measure the masses of 90 ground and 8 isomeric states of neutron-deficient nuclides with a typical precision of better than 10keV. The masses of 14 nuclides -- 84Zr , 88, 89Tc , 90-92Ru , 92-94Rh , 94, 95Pd , 106, 108, 110Sb -- have been experimentally determined for the first time. This article gives an overview on these measurements and their impact on the modeling of the astrophysical rp -process. peerReviewed
Direct measurement of the mass difference of $^{72}$As-$^{72}$Ge rules out $^{72}$As as a promising $\beta$-decay candidate to determine the neutrino…
2021
We report the first direct determination of the ground-state to ground-state electron-capture $Q$-value for the $^{72}$As to $^{72}$Ge decay by measuring their atomic mass difference utilizing the double Penning trap mass spectrometer, JYFLTRAP. The $Q$-value was measured to be 4343.596(75)~keV, which is more than a 50-fold improvement in precision compared to the value in the most recent Atomic Mass Evaluation 2020. Furthermore, the new $Q$-value was found to be 12.4(40)~keV (3.1 $\sigma$) lower. With the significant reduction of the uncertainty of the ground-state to ground-state $Q$-value value combined with the level scheme of $^{72}$Ge from $\gamma$-ray spectroscopy, we confirm that th…
Trans-Contextual Model Predicting Change in Out-of-School Physical Activity: A One-Year Longitudinal Study
2021
The aim of the current study was to test the long-term predictive validity of the trans-contextual model in accounting for variance in adolescents’ out-of-school physical activity measured by self-report and accelerometer based-devices over a one-year period. Secondary school students ( N = 265) aged 11 to 15 years completed a three-wave survey on two occasions in time, spanning a one-year interval, measuring perceived autonomy support in physical education (PE), peer and parent autonomy support in leisure-time, autonomous and controlled motivation in PE and leisure-time, attitude, subjective norms, perceived behavioural control, intention, and out-of-school physical activity both by sel…
Prometheus-leirit kasvun areenana
2019
Artikkelissa käsitellään Prometheus-leirien vaikutusta leiriläisiin. Tutkimus on monimenetelmäinen aineistolähtöinen tutkimus ja asettuu nuorisotutkimuksen monitieteiseen kenttään. Tulkinnat pohjautuvat leirien osallistujilta leirikesän 2017 aikana ja jälkeen koottuihin kirjoitelmiin ja videopäiväkirjoihin sekä verkkokyselyyn. Tutkimusote korostaa leiriläisten omia tulkintoja. Jäsentävänä käsitteenä käytetään maailmankuvien kehitystä. Aineistossa rakentuu tarina itseymmärryksen syvenemisestä ja leirin vaikuttavuuden prosessinomaisuudesta. Leirien vaikutus näyttää myös keskittyvän pikemminkin sosiaalisiin taitoihin kuin tietoon. peerReviewed
Students’ physical activity intensity and sedentary behaviour by physical self-concept profiles : A latent profile analysis
2020
Aims of this study were to identify student clusters in physical appearance, sport competence, global physical self-concept and self-esteem, and to examine whether different physical self-concept groups differ in their moderate-to-vigorous physical activity (MVPA) and sedentary behaviour. Participants of the study were 211 boys and 183 girls aged 13-16 years. MVPA and sedentary behaviour were monitored by GT3X accelerometers during seven days. Participants' physical self-concept was measured by the short Physical Self-Description Questionnaire. Latent profile analyses revealed a four-cluster solution: 1) "low sport competence, moderate global physical self-concept and self-esteem, and high …