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Prediction of the first 2^(+) states properties for atomic nuclei using light gradient boosting machine

nuclear Science and Techniques 2025年第2期36卷 95-102页

作者： Hui Liu Xin-Xiang Li Yun Yuan Wen Luo Yi Xu School of Nuclear Science and Technology University of South ChinaHengyang 421001China Extreme Light Infrastructure-Nuclear Physics(ELI-NP) Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering(IFIN-HH)Strada Reactorului 30Buchurest-Magurele077125 IlfovRomania

The first 2^(+)excited states of the nucleus directly reflect the interaction between the shell structure and the nucleus,providing insights into the validity of the shell model and nuclear structure *** the features of the first 2^(+)excited states can be measured for stable nuclei and calculated using nuclear models,significant uncertainty *** study employs a machine learning model based on a light gradient boosting machine(LightGBM)to investigate the first 2^(+)excited ***,the training of the LightGBM algorithm and the prediction of the first 2^(+)properties of 642 nuclei are ***,detailed comparisons of the LightGBM predictions were performed with available experimental data,shell model calculations,and Bayesian neural network *** results revealed that the average difference between the LightGBM predictions and the experimental data was 18 times smaller than that obtained by the shell model and only 70%of the BNN prediction *** Mg,Ca,Kr,Sm,and Pb isotopes as examples,it was also observed that LightGBM can effectively reproduce the magic number mutation caused by shell effects,with the energy being as low as 0.04 MeV due to shape ***,we believe that leveraging LightGBM-based machine learning can profoundly enhance our insights into nuclear structures and provide new avenues for nuclear physics research.

关键词： First 2^(+) state nuclear levels Light gradient boosting machine

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Latest results from precision measurements at the NA62 experiment 31

Latest results from precision measurements at the NA62 exper...

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31st International Workshop on deep Inelastic Scattering, dIS 2024

作者： Boboc, Petre-Constantin Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering 30 Reactorului Str. Măgurele Romania

Then NA62 experiment at CErN collected the world's largest dataset of charged Kaons, the main goal being the measurement of the B(K+ → π+ν(Equation presented)). New results from the analyses of rare kaon and pion decays using data samples collected in 2017-2018 are presented. A sample of π0 → e+e- decays was collected and preliminary results of the branching ratio are reported. Also, a sample of K+ → π+γγ decays was collected and measurement of the branching ratio, study of the di-photon mass spectrum, and the first search for production and prompt decay of an axion-like particle with gluon coupling in the process K+ → π+A, A → γγ are reported. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-Noderivatives 4.0 International License (CC BY-NC-Nd 4.0).

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A semiclassical perspective on nuclear chirality

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Frontiers of physics 2024年第2期19卷 39-52页

作者： radu Budaca “Horia Hulubei”National Institute for R&D in Physics and Nuclear Engineering Str.Reactorului 30RO-077125POB-MG6 Bucharest-MǎgureleRomania Academy of Romanian Scientists Splaiul Independenţei 54050044BucharestRomania

The application of the semiclassical description to a particle-core system with imbued chiral symmetry is *** classical features of the chiral geometry in atomic nuclei and the associated dynamics are investigated for various core deformations and single-particle *** dynamical characteristics are identified in specific angular momentum ranges,triaxiality and alignment *** observables will be extracted from the classical picture for a quantitative description of experimental data provided as numerical examples of the model’s performance.

关键词： chiral symmetry triaxial nuclei semiclassical description

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BULK ETCHING rATE ASSESSMENT FOr POLYMEr TrACK rAdIATION dETECTOrS

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UPB Scientific Bulletin, Series A: Applied Mathematics and physics 2024年第3期86卷 136-144页

作者： Popovici, Mara-Georgiana dinescu, Eliza Irina Avram, Irina Chiriță, Eugenia-Mihaela Mitu, Iani-Octavian Gheorghiu, Cristina Constanta Extreme Light Infrastructure – Nuclear Physics "Horia Hulubei" National Institute for R&D in Physics and Nuclear Engineering Romania Nuclear Physics Department "Horia Hulubei" National Institute for R&D in Physics and Nuclear Engineering Romania National University of Science and Technology POLITEHNICA Bucharest Romania

Poly(Allyl diglycol Carbonate) (PAdC) detectors are widely used in nuclear particles detection due to their high sensitivity. Particles impinging the polymer form latent tracks which are enlarged through a chemical etching process. This study presents a quantitative assessment of the bulk etching rate obtained by two approaches: (i) mass difference and (ii) fission fragments method. Bulk etching rate is the main parameter reflecting the etching procedure’s efficiency and tracks development. The obtained values of this parameter are furthermore important for the tracks reading and counting processes relevant for dosimetry applications. We present the results obtained through the above-mentioned methods applied on detectors that have been exposed to Th-228 and Cf-252 radioactive sources. © 2024, Politechnica University of Bucharest. All rights reserved.

关键词： Etching

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radiation-resistant Bismuth-doped Germanosilicate Fiber Amplifier in the E+S Band

Radiation-resistant Bismuth-doped Germanosilicate Fiber Ampl...

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CLEO: Science and Innovations in CLEO 2024, CLEO: S and I 2024 - Part of Conference on Lasers and Electro-Optics

作者： Zhai, Ziwei Halder, Arindam Negut, daniel Sahu, Jayanta K. Optoelectronics Research Centre University of Southampton SouthamptonSO17 1BJ United Kingdom Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering MagureleRO-077125 Romania

We report a radiation-resistant Bi-doped germanosilicate fiber amplifier with a 35dB gain at 1440nm after 2.5kGy γγ-irradiation, for a -23dBm input signal. The NF, in-band OSNr, and gain coefficient are 6dB, 26dB, a... 详细信息

关键词： Gamma rays

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radiation-resistant Bismuth-doped Germanosilicate Fiber Amplifier in the E+S Band

Radiation-resistant Bismuth-doped Germanosilicate Fiber Ampl...

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2024 Conference on Lasers and Electro-Optics, CLEO 2024

We report a radiation-resistant Bi-doped germanosilicate fiber amplifier with a 35dB gain at 1440nm after 2.5kGy γ-irradiation, for a -23dBm input signal. The NF, in-band OSNr, and gain coefficient are 6dB, 26dB, and... 详细信息

ISBN: (纸本)9781957171395

关键词： Fiber amplifiers

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Multiple shape coexistence in Zr98 and first-forbidden β decay of Y98

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Physical review C 2025年第1期111卷 014307-014307页

作者： A. Petrovici O. Andrei Horia Hulubei National Institute for Physics and Nuclear Engineering R-077125 Bucharest Romania

The multifaceted impact of shape coexistence on the first-forbidden β− decay of the 0− ground state of Y98 and the structure and dynamics of the populated low-spin states in Zr98 have been investigated within the complex excited Vampir variational model using an effective interaction derived from a G matrix based on the charge-dependent Bonn Cd potential and a large model space. The effects of shape coexistence and mixing revealed by the properties of the investigated β decay of Y98 and the coexistence phenomena at low angular momentum in Zr98 are discussed and comparison to the available data is presented.

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Shape coexistence and first-forbidden decay of rb92 to Sr92

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Physical review C 2024年第2期109卷 024303-024303页

作者： A. Petrovici Horia Hulubei National Institute for Physics and Nuclear Engineering R-077125 Bucharest Romania

The effects of shape coexistence on first-forbidden β− decay of the 0− ground state of rb92 to the 0+ ground state and 2+ states in Sr92 were studied within the beyond-mean-field complex excited Vampir variational model. The structure of the parent and daughter states and the β-decay properties were investigated using an effective interaction derived from a G matrix based on the charge-dependent Bonn Cd potential and a large model space. The effects of shape coexistence and mixing revealed by the structure of the involved states on the properties of the investigated ground state to ground state and first-forbidden unique transitions are discussed and comparison to the available data is presented.

关键词： Beta decay nuclear many-body theory nuclear shapes and moments nuclear structure & decays 90 ≤ A ≤ 149

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Exploring fs-laser irradiation damage subthreshold behavior of dielectric mirrors via electrical measurements

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High Power Laser Science and engineering 2024年第2期12卷 24-32页

作者： Petrisor Gabriel Bleotu radu Udrea Alice dumitru Olivier Uteza Maria-diana Mihai dan Gh Matei daniel Ursescu Stefan Irimiciuc Valentin Craciun Extreme Light Infrastructure-Nuclear Physics(ELI-NP) Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering(IFIN-HH)MagureleRomania Doctoral School of Physics University of BucharestMagureleRomania LULI-CNRS CEAUniversite SorbonneEcole PolytechniqueInstitut Polytechnique de ParisPalaiseau CEDEXFrance Apel Laser IlfovRomania Aix-Marseille University CNRSLP3 UMR 7341MarseilleFrance Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering(IFIN-HH) MagureleRomania University Politehnica of Bucharest BucharestRomania National Institute for Lasers Plasma and Radiation Physics MagureleRomania

With ultrafast laser systems reaching presently 10 PW peak power or operating at high repetition rates,research towards ensuring the long-term,trouble-free performance of all laser-exposed optical components is *** work is focused on providing insight into the optical material behavior at fluences below the standardized laser-induced damage threshold(LIdT)value by implementing a simultaneous dual analysis of surface emitted particles using a Langmuir probe(LP)and the target current(TC).HfO_(2) and ZrO_(2) thin films deposited on fused silica substrates by pulsed laser deposition at various O_(2) pressures for defect and stoichiometry control were irradiated by Gaussian,ultrashort laser pulses(800 nm,10 Hz,70 fs)in a wide range of *** TC and LP collected signals were in good agreement with the existing theoretical description of laser–matter interaction at an ultrashort time *** approach for an in situ LIdT monitoring system provides measurable signals for below-threshold irradiation conditions that indicate the endurance limit of the optical surfaces in the single-shot energy scanning *** LIdT value extracted from the LP-TC system is in line with the multipulse statistical analysis done with ISO 21254-2:2011(E).The implementation of the LP and TC as on-shot diagnostic tools for optical components will have a significant impact on the reliability of next-generation ultrafast and high-power laser systems.

关键词： HfO_(2) in situ detection Langmuir probe laser-induced damage threshold target current ZrO_(2)

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Comparative biomonitoring of airborne potentially toxic elements using mosses (Hypnum cupressiforme, Brachythecium spp.) and lichen (Evernia prunastri) over remote areas

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Environmental Science and Pollution research 2024年第35期31卷 48296-48312页

作者： Aničić Urošević, Mira Ilić, Miloš radnović, dragan Vergel, Konstantin Yushin, Nikita Chaligava, Omari Zinicovscaia, Inga Institute of Physics Belgrade University of Belgrade Pregrevica 118 Belgrade11080 Serbia Department of Biology and Ecology University of Novi Sad Faculty of Sciences Trg Dositeja Obradovića 3 Novi Sad21000 Serbia Frank Laboratory of Neutron Physics Joint Institute for Nuclear Research Joliot Curie 6 Dubna141980 Russia Horia Hulubei National Institute for R & amp D in Physics and Nuclear Engineering 30 Reactorului Str. MG-6 Bucharest Magurele Romania

The selection of the appropriate biomonitor species is a crucial criterion for biomonitoring on a broad spatial scale. Mosses Hypnum cupressiforme and Brachythecium spp. and lichen Evernia prunastri were sampled at 22 remote sites over Serbia aiming interspecies comparison of their bioconcentration capacities. The concentration of 16 potentially toxic elements (PTEs), Al, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, P, Pb, S, Sr, V, and Zn, was measured in the samples. Between the co-located mosses, linear regression analysis (type II) showed significant determination coefficients only for a couple of the elements (Cd and S), while for H. cupressiforme vs. lichen, significant regression lines were obtained for a broader set of elements (Ba, Cd, Fe, Hg, Mn, Ni, Sr). The ratio of the PTEs in the mosses discovered higher concentrations in H. cupressiforme than in another moss at some sites and vice versa at other sites. According to the PTE ratios, H. cupressiforme accumulated much more element content than the lichen, but followed a similar spatial pattern. In addition, principal component analysis (PCA) pointed out a different grouping of the PTEs depending on the species tested. The poor correlation of the moss-moss data is perhaps because several species of the genus Brachythecium were sampled, which possibly influenced the average genus accumulation capacity. In addition, morphological features of the mosses (concave vs. flat leaflets, creeping vs. cushiony life form) presumably delegate differences in PTE accumulation. To conclude, it should be careful with using more biomonitor species, even of the same genus, within the same study. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.

关键词： Principal component analysis

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