Ł. W. Iskra
A5055290579- Nuclear physics research studies
- Nuclear Physics and Applications
- Astronomical and nuclear sciences
- Advanced NMR Techniques and Applications
- Quantum Chromodynamics and Particle Interactions
- Atomic and Molecular Physics
- Nuclear reactor physics and engineering
- Advanced Chemical Physics Studies
- Radiation Detection and Scintillator Technologies
- Nuclear Materials and Properties
- Atomic and Subatomic Physics Research
- Particle physics theoretical and experimental studies
- Particle Detector Development and Performance
- Isotope Analysis in Ecology
- Neutrino Physics Research
- Ion-surface interactions and analysis
- Scientific Research and Discoveries
- Radiation Therapy and Dosimetry
- Diamond and Carbon-based Materials Research
- Geophysics and Gravity Measurements
- Quantum, superfluid, helium dynamics
- Advanced MRI Techniques and Applications
- Radiation Effects in Electronics
- Dark Matter and Cosmic Phenomena
- Radioactive element chemistry and processing
Institute of Nuclear Physics, Polish Academy of Sciences
2016-2025
Istituto Nazionale di Fisica Nucleare, Sezione di Milano
2019-2023
Maj Institute of Pharmacology
2023
University of Milan
2019-2021
Istituto Nazionale di Fisica Nucleare
2020-2021
Polish Academy of Sciences
2020
The low-spin structure of the 206Tl nucleus was studied in thermal neutron capture reaction 205Tl(𝑛,𝛾)206Tl at Institut Laue-Langevin Grenoble making use multidetector HPGe array Fission Product Prompt 𝛾-ray Spectrometer and 𝛾𝛾-coincidence techniques. information on discrete structures located below binding energy extended: a total number 99 𝛾 rays (75 new) were observed 21 excited states (8 located. analysis angular correlations used to extract transitions multipolarities, which helped...
A search for shape isomers in the ^{66}Ni nucleus was performed, following old suggestions of various mean-field models and recent ones, based on state-of-the-art Monte Carlo shell model (MCSM), all considering as lightest nuclear system with isomerism. By employing two-neutron transfer reaction induced by an ^{18}O beam a ^{64}Ni target, at sub-Coulomb barrier energy 39 MeV, three lowest-excited 0^{+} states were populated their γ decay observed γ-coincidence technique. The lifetimes...
Excited states in ${}^{64}$Ni, ${}^{66}$Ni, and ${}^{68}$Ni were populated quasielastic deep-inelastic reactions of a 430-MeV ${}^{64}$Ni beam on thick ${}^{238}$U target. Level schemes including many nonyrast established up to respective excitation energies 6.8, 8.2, 7.8 MeV the basis \ensuremath{\gamma}-ray coincidence events measured with Gammasphere array. Spin-parity assignments deduced from an angular-correlation analysis observed \ensuremath{\gamma}-decay patterns, but information...
The low-spin structure of the semimagic ^{64}Ni nucleus has been considerably expanded: combining four experiments, several 0^{+} and 2^{+} excited states were identified below 4.5 MeV, their properties established. Monte Carlo shell model accounts for results unveils an unexpectedly complex landscape coexisting shapes: a prolate excitation is located at surprisingly high energy (3463 keV), with collective state 286 keV above it, first such observation in Ni isotopes. evolution minimum...
Multinucleon transfer reactions were employed in a series of experiments at Legnaro National Laboratories INFN and the Tandem Laboratory Horia Hulubei Institute Bucharest. The main aim was to investigate shape coexistence phenomenon even–even Sn isotopes, with mass \(A=112\)–118, through lifetime measurements excited \(0^+\) states. Recent Monte Carlo Shell Model (MCSM) calculations predict, fact, appearance well-separated secondary minima potential energy surfaces these corresponding...
Fission shape isomers (SI) are poorly understood metastable states characterized by a second super-deformed potential energy minimum coexisting with normally-deformed in the low-spin regime. Although many such have been observed actinide region, our understanding of remains very limited. For most SIs, only available information is their half-life, determined via exclusive decay mode, delayed fission. However, interesting possibility competing branch \(\gamma \)-back towards opens up as...
The level scheme of the neutron-rich \(^{87}\)Se isotope has been extended up to 2397 keV excitation energy. interest was produced in a neutron-induced fission reaction \(^{235}\)U target at Institut Laue-Langevin Grenoble. During analysis, six new gamma transitions were identified by employing multifold gamma-ray coincidence relationships, measured with FIPPS array. Based on angular correlations technique, tentative spin-parity assignments have proposed for low-lying levels. Abstract...
Excited states above the seniority $\ensuremath{\nu}=2$ isomers have been investigated in even neutron-rich ${}^{118--128}$Sn isotopes produced by fusion-fission of 6.9 MeV/$A$ $^{48}\mathrm{Ca}$ beams with $^{208}\mathrm{Pb}$ and $^{238}\mathrm{U}$ targets fission 6.7 $^{64}\mathrm{Ni}$ on a target. Level schemes up to excitation energies excess 8 MeV established based multifold $\ensuremath{\gamma}$-ray coincidence relationships measured Gammasphere array. Isotopic identification crucial...
The level scheme of 96Y was significantly extended and a new 201 ns isomer located at 1655 keV excitation energy, with spin-parity assignment 5± or 6−. decays to spherical low-spin structure by transitions large hindrance is fed short cascade which resembles the beginning rotational band. This in analogy feeding decay pattern 4− 98Y, here confirmed, lifetime analysis, as bandhead sizable deformation. It suggested that arises from shape change between deformed configurations, indicates...
The nucleus ${}^{208}$Pb provides an iconic test of the nuclear shell model because its 82 protons and 126 neutrons are both magic numbers. When excited levels discovered characterized, this a means to investigate mechanisms responsible for generation angular momentum and, ultimately, development collectivity. This experiment is tour de force that reveals extensive new information on about high-angular-momentum states, isomeric collective states octupole nature; thus it serves as showcase...
To test the predictive power of ab initio nuclear structure theory, lifetime second 2+ state in neutron-rich 20O, tau(2+_2 ) = 150(+80-30) fs, and an estimate for 16C have been obtained, first time. The results were achieved via a novel Monte Carlo technique that allowed us to measure lifetimes tens-to-hundreds femtoseconds range, by analyzing Doppler-shifted gamma-transition line shapes products low-energy transfer deep-inelastic processes reaction 18O (7.0 MeV/u) + 181Ta. requested...
Excited states in 98Y, populated neutron-induced fission of 235U and spontaneous 248Cm 252Cf, have been studied by means γ spectroscopy using the Lohengrin fission-fragment separator at ILL Grenoble EXILL, Eurogam2, Gammasphere Ge arrays. Two new isomers found 98Y: a deformed one with T1/2=180(7) ns rotational band on top it, spherical T1/2=0.45(15)μs, analogous to 8+ isomer 96Y, corresponding (νg7/2,πg9/2)8+ configuration. Using JYFLTRAP Penning trap, an accurate excitation energy 465.7(7)...
The B(E3) transition strength from the 1897-keV, 3− level in 96Zr has been reevaluated six high-statistics, independent data sets. measured value of 42(3) W.u. is significantly lower than that adopted recent compilations. It is, however, line with global systematics collective rates found throughout periodic table. Thus, "exceptional" character this transition, challenged theory, no longer applies. Monte Carlo shell-model calculations indicate collectivity octupole vibration arises both...
We report on spectroscopic information and lifetime measurements of even-even neutron-rich Te isotopes. Excited states were populated in fast-neutron induced fission $^{238}\mathrm{U}$ at the ALTO facility IJCLab with LICORNE neutron source detected using hybrid $\ensuremath{\nu}$-ball spectrometer. provide first results lifetimes ${6}_{1}^{+}$ state $^{136}\mathrm{Te}$ (${6}_{1}^{+}$), (${4}_{1}^{+}$), (${2}_{1}^{+}$) $^{138}\mathrm{Te}$ discuss context large-scale shell-model calculations....
Yrast and near-yrast levels up to an $I=17\ensuremath{\hbar}$ spin value a 6-MeV excitation energy have been delineated in the ``two-neutron'' $^{210}\mathrm{Pb}$ nucleus following deep-inelastic reactions involving $^{208}\mathrm{Pb}$ targets number of heavy-ion beams at energies $\ensuremath{\sim}25%$ above Coulomb barrier. The level scheme was established on basis multifold prompt delayed coincidence relationships measured with Gammasphere array. In addition previously known states, many...
We report on the first measurement of half-lives Kπ=11− and 12+ four-quasiparticle states in even-even nucleus 178W. The sub-nanosecond were measured by applying centroid shift method to data taken with LaBr3(Ce) scintillator detectors NuBall array at ALTO facility Orsay, France. these only became experimentally accessible combination several experimental techniques - fast timing, isomer spectroscopy a pulsed beam, event-by-event calorimetry information provided array. are 476(44)ps...
Excited states with seniority $\ensuremath{\nu}=3$, 5, and 7 have been investigated in odd neutron-rich $^{119,121,123,125}\text{Sn}$ isotopes produced by fusion-fission of 6.9-MeV/$A\phantom{\rule{4pt}{0ex}}^{48}\text{Ca}$ beams $^{208}\text{Pb}$ $^{238}\text{U}$ targets fission a target bombarded 6.7-MeV/$A\phantom{\rule{4pt}{0ex}}^{64}\text{Ni}$ beams. Level schemes established up to high spin excitation energies excess 6 MeV, based on multifold gamma-ray coincidence relationships...
The population of isomeric states in the prompt decay fission fragments---so-called yield ratios (IYRs)---is known to be sensitive angular momentum $J$ that fragment emerged with, and may therefore contain valuable information on mechanism behind process. In this work, we investigate how changes fissioning system impact measured IYRs fragments learn more about what parameters affect generation. To enable this, a new technique for measuring is first demonstrated. It based time arrival...
Cross sections and corresponding momentum distributions have been measured for the first time at zero degrees exotic nuclei obtained from a beam of 18O 8.5 MeV/A impinging on 1 mg/cm2 238U target. Sizable cross were found production species arising neutron transfer proton removal projectile. Comparisons experimental results with calculations based deep-inelastic reaction models, taking into account particle evaporation process, indicate that degree is scattering angle which differential...
An in-beam test of two pixel-type silicon detectors the TRACE detector project has been performed at Laboratori Nazionali di Legnaro (Italy). The aim was to investigate lowest kinetic energy values which isotopic identification heavy-ion reactions products with mass $ A\sim 10$ is possible, by using a single-layer detector. Two separate read-out chains, analog and digital, were used, Pulse Shape Analysis technique employed obtain particle matrices for digitally processed data. results...
On
We report on the measurement of lifetimes excited states in near-mid-shell nuclei $^{164,166}\mathrm{Dy}$ using gamma-ray coincidence fast-timing method. The interest were populated reactions between an $^{18}\mathrm{O}$ beam and a gold-backed isotopically enriched $^{164}\mathrm{Dy}$ target thickness $6.3\phantom{\rule{4pt}{0ex}}\mathrm{mg}/{\mathrm{cm}}^{2}$ at primary energies 71, 76, 80 MeV from IPN-Orsay laboratory, France. Excited $^{164}\mathrm{Dy}$, $^{166}\mathrm{Dy}$,...
The γ decay of the elusive narrow, near-threshold proton resonance in 11B was investigated at Laboratori Nazionali di Legnaro (INFN) a particle-γ coincidence experiment, using 6Li(6Li,pγ) fusion-evaporation reaction and GALILEO-GALTRACE setup. No clear signature found for possible E1 to 1/21−, first-excited state 11B, predicted by Shell Model Embedded Continuum (SMEC) with branching 0.98−69+167×10−3 respect dominant particle-decaying modes. statistical analysis γ-ray spectrum provided an...