BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Breakup of fission fragments when passing foil from C and Ta. DTSTART;VALUE=DATE-TIME:20261030T141000Z DTEND;VALUE=DATE-TIME:20261030T142500Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6355@cern.ch DESCRIPTION:Speakers: Yury Pyatkov (Joint Institute for Nuclear Research)\ nIn our previous publications [1-5] we presented experimental evidences of rare ternary decay mode unknown in the past in which some fraction of fis sion fragments (FFs) born during binary fission of low excited heavy nucle i undergo a break-up\, while they pass a solid-state foil. Experimental ev idences obtained so far allowed us to suppose that such FFs are formed in the shape-isomer states. Since the decay is caused by the Coulomb interact ion of the fragment with the foil nucleus [6]\, it's important to figure o ut how the foil's nuclear charge affects the process parameters. New resul ts obtained in our experiments with light carbon and heavy Ta foils are pr esented.\nReferences\n1. Yu.V. Pyatkov et al.\, Eur. Phys. J. A 45\, 29 (2 010).\n2. Yu.V. Pyatkov et al.\, Eur. Phys. J. A 48\, 94 (2012).\n3. Yu.V. Pyatkov et al.\, Phys. Rev. C 96 (2017) 064606. \n4. Yu. V. Pyatkov et al .\, Physics of Atomic Nuclei\, 85\, 763 (2022)\n5. D. V. Kamanin et al.\, International Journal of Modern Physics E Vol. 34\, Nos. 2 & 3 (2025) 2541 002\n6. F. O. Otakhonov et al.\, Phys. Lett. B 872 (2026) 140088\n\nhttps: //indico.particle.mephi.ru/event/626/contributions/6355/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6355/ END:VEVENT BEGIN:VEVENT SUMMARY:Study of the excited 8.1 MeV state of $^{11}$C DTSTART;VALUE=DATE-TIME:20261030T152500Z DTEND;VALUE=DATE-TIME:20261030T154000Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6359@cern.ch DESCRIPTION:Speakers: Andrey Danilov (NRC Kurchatov Institute)\nThe $^{11} $C nucleus is a proton-rich nucleus with intriguing exotic features. Unlik e the neutron-rich $^{11}$Be nucleus\, isobar analog with a confirmed neut ron halo\, $^{11}$C does not form a pronounced proton halo due to the Coul omb barrier. \n\nThe results of an experimental study of the structure of $^{11}$C using the transfer reaction $^{10}$B($^{7}$Li\,$^6$He)$^{11}$C at a beam energy of 58 MeV\, carried out at the U400 cyclotron at JINR\, are presented. The main focus is on a detailed analysis of the excited state with an energy of 8.1 MeV. Using a multi-stage identification procedure an d kinematic calculations\, it was possible to reliably separate the peak u nder study from the contributions of parasitic impurities $^{12}$C and $^{ 16}$O in the operating angle range\, ensuring high purity of experimental data. \n\nThe distorted waves method was used to interpret the obtained an gular distributions of differential cross sections. The analysis showed th at the radial dependence of the form factor for the 8.1 MeV state decrease s significantly more slowly (has a longer "tail") compared to the ground s tate. This directly indicates an abnormally large root mean square radius of this level. The obtained results became the first experimental evidence of the increased size of the 8.1 MeV state in the $^{11}$C nucleus. Its s patial dimensions turned out to be comparable to the radius of the Hoyle s tate in $^{12}$C and the mirror level in $^{11}$B. This is consistent with the theoretical predictions of the antisymmetrized molecular dynamics (AM D) model and confirms the presence of an exotic three center cluster struc ture 2α + $^3$He\, which allows us to confidently assign this level to th e class of “size isomers”.\n\nhttps://indico.particle.mephi.ru/event/6 26/contributions/6359/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6359/ END:VEVENT BEGIN:VEVENT SUMMARY:The production of trineutron states after stopped pion absorption by 9Be nuclei DTSTART;VALUE=DATE-TIME:20261030T154000Z DTEND;VALUE=DATE-TIME:20261030T155500Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6358@cern.ch DESCRIPTION:Speakers: Boris Chernyshev (National Research Nuclear Universi ty MEPhI)\nThe search for the trineutron $^{3}$n was carried out in the re actions of stopped pion absorption $^{9}Be(\\pi^{-}\,d^{4}He)^{3}n$ and $^ {9}Be(\\pi^{-}\,t^{3}He)^{3}n$. Correlation measurements of the missing ma ss spectra were performed using the multilayer semiconductor spectrometer (M. G. Gornov et al.\, Nucl. Instrum. Methods Phys. Res. A\, 446\, 461 (20 00)). No indications of the existence of bound states of the trineutron we re obtained in the measurements of both reactions. Near the threshold ($E_ {r} \\ge 0 MeV$)\, an excess of the experimental spectrum over the calcula ted one was observed. However\, the insufficient statistics of the data in this region did not allow the determination of the resonance parameters o f this excess. In both reactions\, indications were obtained of the existe nce of two relatively narrow ($\\Gamma \\cong 3 MeV$) resonance states wit h $E_{r} \\cong 6$ and 14 MeV. Several theoretical works [F. M. Marqués a nd J. Carbonell\, EPJA\, 57\, 105 (2021)] predict the existence of such hi gh lying 3n states with significantly larger widths (Γ $\\sim$ 10 MeV).\n \nhttps://indico.particle.mephi.ru/event/626/contributions/6358/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6358/ END:VEVENT BEGIN:VEVENT SUMMARY:High-Precision Physics with Heavy Ions DTSTART;VALUE=DATE-TIME:20261030T161000Z DTEND;VALUE=DATE-TIME:20261030T162500Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6357@cern.ch DESCRIPTION:Speakers: Dmitry Glazov (ITMO University)\nModern experiments with heavy highly charged ions provide unique opportunities to probe quant um electrodynamics in the strong-field regime\, determine fundamental cons tants and nuclear properties\, and search for physics beyond the Standard Model. The combination of high nuclear charge\, simple few-electron struct ure\, and advanced experimental techniques enables precision tests of QED in regimes inaccessible to conventional experiments. In particular\, measu rements of atomic transition frequencies and bound-electron g-factors prov ide sensitive probes of electron-nucleus and electron-electron interaction s\, nuclear structure\, and higher-order QED effects. Heavy ions also offe r promising platforms for searches for new interactions and ultralight dar k matter through precision spectroscopy. This talk will review recent theo retical and experimental developments in high-precision studies of highly charged ions and discuss their prospects for probing fundamental physics.\ n\nhttps://indico.particle.mephi.ru/event/626/contributions/6357/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6357/ END:VEVENT BEGIN:VEVENT SUMMARY:STUDY OF NEUTRON REMOVAL MECHANISMS IN THE 9Be(7Be\, 6Be)X REACTIO N AT INTERMEDIATE ENERGIES DTSTART;VALUE=DATE-TIME:20261030T151000Z DTEND;VALUE=DATE-TIME:20261030T152500Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6356@cern.ch DESCRIPTION:Speakers: Danila Makarov (Flerov Laboratory of Nuclear Reactio ns\, JINR\, Dubna\, Russia\; National Research Nuclear University MEPhI\, Moscow\, Russia)\nIn this work\, the population mechanisms of the ^{6}Be n uclear states in the ^{9}Be(^{7}Be\, ^{6}Be)X neutron removal reaction at a beam energy of 67 MeV/nucleon are investigated using theoretical models of increasing complexity. The analyzed experimental data were obtained at the National Superconducting Cyclotron Laboratory (NSCL\, MSU\, USA) in 20 11 and stand out as a record in terms of statistics and detail for radioac tive ion beam reaction studies. Previously\, these data were analyzed excl usively from the perspective of the ^{6}Be → ^{4}He+p+p decay\, utilizin g the simplest "sudden removal approximation"\, where the transition ampli tude is expressed via the projectile form factor. However\, this model pro ves unsatisfactory as it fails to describe the experimental results even a t a qualitative level.\n\nThe simplest model that satisfies energy-momentu m conservation and allows for a semi-analytical treatment is the "quasi-fr ee scattering" model formulated within the Plane Wave Born Approximation ( PWBA). This approach describes the scattering of a projectile nucleon on t he target nucleus as a whole. To perform a meaningful comparison with expe riment\, target thickness effects\, detector geometry constraints\, and in elasticity effects in the ^{9}Be+n channel were incorporated into the mode l. Nevertheless\, this approximation managed to reproduce only a fraction of the momentum distribution. However\, incorporating absorption in the pa rticipant-target channel within the PWBA framework can only reproduce the data using unrealistic model parameters.\n\nFor a complete description of the experimental data\, a new model describing neutron scattering on indiv idual target nucleons has been developed\, provisionally named "symmetric quasi-free scattering". When combined with the PWBA formalism and adjusted for target thickness and detector array geometry\, this model successfull y describes the experimental data with high accuracy for both low-lying an d highly excited states. Furthermore\, the data obtained in the same exper iment for the two-body decay channel ^{6}Be → ^{3}He+^{3}He also demonst rate good agreement with this approximation.\n\nThis report presents a com parative analysis of the experimental data interpreted within the sudden r emoval approximation\, the standard PWBA formalism\, and the "symmetric qu asi-free scattering" model for both low-lying and highly excited states in the three-body ^{6}Be → ^{4}He+p+p decay channel. Additionally\, simula tion results obtained using the "symmetric quasi-free scattering" model an d the PWBA formalism for the two-body ^{6}Be → ^{3}He+^{3}He decay chann el are demonstrated.\n\nReferences\n1. L. V. Grigorenko et al. Phys. Lett. B 677\, 30–35 (2009).\n2. I. A. Egorova et al. Phys. Rev. Lett. 109\, 2 02502 (2012).\n3. L. V. Grigorenko et al. Phys. Rev. C 80\, 034602 (2009). \n\nhttps://indico.particle.mephi.ru/event/626/contributions/6356/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6356/ END:VEVENT BEGIN:VEVENT SUMMARY:Analysis of the $^{13}$C(d\,p)$^{14}$C reaction in the energy rang e of 13–18 MeV: determination of empirical form factors and ANC DTSTART;VALUE=DATE-TIME:20261030T145500Z DTEND;VALUE=DATE-TIME:20261030T151000Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6354@cern.ch DESCRIPTION:Speakers: Alla Demyanova (NRC Kurchatov Institute\, 1\, Akadem ika Kurchatova pl.\, Moscow\, 123182\, Russia)\nNew differential cross sec tions for the single proton transfer reaction $^{13}$C(d\,p)$^{14}$C at a deuteron energy of 18 MeV are presented for the ground state 0+ and three excited states: 6.094 MeV (1$^−$)\; 6.728 MeV (3$^-$)\; 7.341 MeV (2$^ −$) of the product nucleus. The experimental measurements were carried o ut at the U 150M isochronous cyclotron of the Institute of Nuclear Physics in Almaty. The analysis of the obtained data\, together with previously p ublished results\, was carried out within the framework of the distorted w ave method with a finite interaction radius (FRDWBA)\, using precisely sel ected parameters of local optical potentials.\n\nBased on a phenomenologic al approach\, the values of nuclear vertex constants (NVCs) for the excite d states of the 14C nucleus were experimentally determined for the first t ime. The NVC value for the ground state demonstrated excellent agreement w ith independent theoretical calculations. Modeling of angular distribution s showed a high quality of the experiment description in the region of for ward angles (up to 60°)\, which confirms the reliability of the proposed methodology. \n\nAnalysis of radial dependencies revealed important struct ural features of the exotic states of the $^{14}$C nucleus. It was found t hat the form factor of the excited state 1$^−$ (6.094 MeV) has a nodal s tructure that is fundamentally different from the behavior of the ground s tate. Furthermore\, increased root mean square radii were observed for all the investigated excited levels\, which directly indicate an excessive sp atial extent of nuclear matter and is a clear sign of the formation of a n eutron halo.\n\nhttps://indico.particle.mephi.ru/event/626/contributions/6 354/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6354/ END:VEVENT BEGIN:VEVENT SUMMARY:Research into d+d Nuclear Reactions in Crystalline Structures Usin g an HELIS Ion Accelerator DTSTART;VALUE=DATE-TIME:20261030T155500Z DTEND;VALUE=DATE-TIME:20261030T161000Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6353@cern.ch DESCRIPTION:Speakers: Mikhail Kirsanov (MEPhI)\nThe study of nuclear fusio n reactions involving light nuclei in crystalline structures is a signific ant topic for both fundamental research and practical applications. Experi mental studies have demonstrated that the processes of deuterium nuclear f usion in solid and gaseous targets differ significantly. A number of exper imental results have been obtained\, indicating the possibility of reducin g the energy required to initiate nuclear reactions in solids due to the e ffects of hydrogen interaction with the crystal lattice. \nUsing the HELIS ion accelerator (Lebedev Physical Institute of the Russian Academy of Sci ences\, Moscow)\, we conducted a series of experiments to investigate d+d nuclear reactions in various crystalline structures. The energy of the deu terium ions varied from 10 to 45 keV\, and the beam current ranged from 20 to 100 μA. Scintillation detectors with organic crystals were used to re gister the neutrons produced in the deuterium fusion reactions. \nThis pap er presents the results of experiments on studying d+d reactions in Pt and Ti metal targets\, as well as in polycrystalline CVD diamond. For the fir st time\, similar experiments were carried out with a B4C ceramic target. The neutron yield from these targets was measured as a function of irradia tion time\, deuterium ion beam parameters\, and target temperature. \nA si mulation of the passage of deuterium ions through the substance of the spe cified targets was carried out. Based on experimental data and the modelin g results\, deuterium concentrations in Pt\, Ti\, CVD diamond\, and B4C we re calculated as functions of irradiation time\, beam current\, deuterium ion energy\, and target temperature. \nThe obtained results are presented in the report.\n\nhttps://indico.particle.mephi.ru/event/626/contributions /6353/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6353/ END:VEVENT BEGIN:VEVENT SUMMARY:Study of solar activity correlations with Fe-55 and Co-60 nuc leus decay parameters DTSTART;VALUE=DATE-TIME:20261030T144000Z DTEND;VALUE=DATE-TIME:20261030T145500Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6352@cern.ch DESCRIPTION:Speakers: Sergey Mayburov (Lebedev inst. of physics)\nTemporal variations of nucleus decay parameters studied extensively in last yea rs\, their observation can be signal of unknown physical effects of co smic origin\, in particular\, induced by solar influence. Several experime nts reported annual and daily decay rate oscillations in α- and β-decay s of some nuclides at the level of .01 % [1]. Also\, correlations of Mn- 54 β-decay rate with solar activity\, in particular\, with X-ray solar flares\, reported [2]. BSTU - PhIAN - ITEP collaboration studies decay rate correlations for Co-60 β-decay and Fe-55 inverse β -decay with sol ar activity.\n Possible influence of solar activity on nucleus d ecay rates was studied during 2022 – 2026 for Fe-55 and Co-60 isotopes by means of decay γ-ray registration by semiconductor detectors. 24 significant decay rate deviations from expected exponential decay rate o f the order .3 % with duration from 50 to 188 hours were found [3\,4]. I t was shown that such rate deviations occur 20 – 80 hours before intens e solar flare event with reliability of 90%.\n X-ray ionizing radia tion produced during intense solar flares can be significant danger for as tronaut health and satellite instrument functioning\, hence development of corresponding warning systems can improve radiation safety of space f lights. “Raspad” project realized now to perform measurements of Fe-5 5\, Co-60 decay rate parameters at International Space Station and Earth l abs to check such methodics \napplicability for that purpose. \n\n \ n 1. E. Alekseev et al. \, Phys. Part. Nucl. 47\, 1803 (2016)\; ibid. 49\, 557 (2018)\n 2. E. Fischbach et al. \, Rev. Space Sci. 145\, 28 5 (2009)\; Astrop. Phys. 59\, 47 (2009)\n 3. S. Bogachev et al. J. Phys.: Conf. Series 1690\, 012028-012035 (2020)\n 4. S. Mayburov et al. Phys. Part. Nucl. 56\, 861 (2025)\n\nhttps://indico.particle.mephi.ru /event/626/contributions/6352/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6352/ END:VEVENT BEGIN:VEVENT SUMMARY:Near-threshold states in dissociation of relativistic nuclei DTSTART;VALUE=DATE-TIME:20261030T142500Z DTEND;VALUE=DATE-TIME:20261030T144000Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6351@cern.ch DESCRIPTION:Speakers: Pavel Zarubin (Joint Institute for Nuclear Research) \nJoint Institute for Nuclear Research\, Dubna\, Russia\nThe use of nuclea r emulsions (NEs) in beams of relativistic nuclei expands the study of nuc lear clustering and\, above all\, resonance states near α-particle separa tion thresholds [nsr-2026]. The current focus is on searching for extremel y low-energy α-particle states\, described as Bose-Einstein condensates. Following the 2α-state of 8Be(0+) and the 3α-state of Hoyle 12C(0+2)\, t he excitation of 16O(0+6) at 15.1 MeV or 296 keV above the 12C(0+2)α thre shold has been proposed as a 4α-condensate. In general\, decays of unstab le states can be identified in distributions of invariant masses Q\, defin ed as sums of the scalar products of the fragment 4-momenta. For convenien ce\, the masses of the fragments or the parent nucleus are subtracted from Q. In the relativistic case\, the 4-momenta are determined with sufficien t accuracy in the approximation of conservation of momentum per nucleon of the parent nucleus from their emission angles. In the dissociation of 12C and 16O nuclei\, the assumption that He fragments correspond to α partic les is justified. Due to their minimal energy\, their decays can manifest themselves as ensembles of relativistic He fragments with the smallest sca ttering angles.\nThe contribution of the 8Be(0+)α channel at Q2α ≤ 200 keV to the dissociation of 12C → 3α at 3.65 GeV per nucleon was determ ined to be 43%\, including 26% through 12C(0+2) at Q3α ≤ 700 keV. The c ontribution of 12C(0+2) to the coherent dissociation of 16O → 4α at 3.6 5 GeV per nucleon was 22%\, significantly increasing compared to the case of 12C (11%). However\, 16O(0+6) at Q4α ≤ 1 MeV did not manifest itself in the 12C(0+2)α and 28Be(0+) channels. Such suppression can be explaine d by the extremely small energy difference between 16O(0+6) and 12C(0+2)α \, leading to a decay width of only 10-9 MeV . At the same time\, the stru cture of 16O(0+6 as 12C(0+2)α\, makes possible the internal conversion of 12C(0+2) to the ground state 12C(0+1) with a width of 0.2 MeV. By allowin g 16O(0+6) to be considered as an excitation near the 4α threshold\, this scenario motivated the search for binary decays 16O(0+6) → 12C(0+1)α p resented here.\nThe distribution over invariant mass of 12Cα pairs produc ed in the dissociation of 16O indicates decays of the excited state 16O(0+ 6). An estimate of the probabilities of the 12C(0+1)α and 12C(0+2)α chan nels indicates a dominance of the former with a factor of about 20. It sup ports the hypothesis of decay of the 16O(0+6) state via internal conversio n of its substructure 12C(0+2) to 12C(0+1). This makes it possible to synt hesize the isotope 12C through the decay 16O(0+6) → 12C(0+2)α → 12C(0 +1)α without a radiative transition as an addition to the known 3α-proce ss.\nThe study of binary dissociation of 16O nuclei stimulated a reanalysi s of data on the α-particle dissociation of 22Ne nuclei for observations of near-threshold resonances\, as follows. The invariant mass distribution of 18Oα pairs produced in the dissociation of 22Ne at 3.22 GeV per nucle on exhibits a peak that can be interpreted as 22Ne excitation with a mean value of approximately 11.6 MeV. Corresponding to sub barrier fusion of 18 O + α\, this observation provides further evidence for the feasibility of nucleosynthesis reactions in the fragmentation cone of relativistic nucle i.\n\n[nsr-2026] D.А. Artemenkov\, A.A. Zaitsev\, P.I. Zarubin “The 8Be nucleus and the Hoyle state in dissociation of relativistic nuclei” Nat ural Sci. Rev. 3 200603 (2026)\nhttps://doi.org/10.54546/NaturalSciRev.200 603\; arXiv:260121425.\n\nhttps://indico.particle.mephi.ru/event/626/contr ibutions/6351/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6351/ END:VEVENT BEGIN:VEVENT SUMMARY:Three-body systems with contact interactions in one dimension DTSTART;VALUE=DATE-TIME:20261028T133500Z DTEND;VALUE=DATE-TIME:20261028T135000Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6350@cern.ch DESCRIPTION:Speakers: Anastasiya Malykh (JINR\, Dubna)\nConsidered are dif ferent one-dimensional three-body systems in the universal \nlow-energy li mit of zero-range two-body interactions.\nIncluded are the two-component s ystem with usual contact interactions and \nthree-component system with im penetrable particles. \nMain attention is paid to the possibility to find analytical results and main \npatterns of the dependencies of bound-state energies and scattering \ncharacteristics on the parameters of systems (in teraction strengths\, masses \nof particles\, parity).\n\nFor a system wit h usual zero-range interaction\, there are few known analytical results\, \nfor example\, for systems with infinite or zero strength of interaction \nbetween identical particles and with equal mass particles or for one hea vy \nand two light particles [1]. \nIn contrast\, for a system with impene trable particles due to correspondence \nto the symmetrical case of usual zero-range model\, it was possible to find \nthe bound-state solution in t he diffraction-free (Bethe ansatz) form [2].\nMoreover\, this model for im penetrable particles is mathematically \nidentical to the problem of refle ction and diffraction of the plane or \nsurface waves by an impedance wedg e described in [3].\nOne more interesting problem to discuss is the scatte ring of dimer on a hard \nwall [4] that corresponds to the three-body syst em in which \none particle has infinite mass. \n\n\n[1] O.I. Kartavtsev\, A.V.Malykh\, S.A. Sofianos\, ZhETF {\\bf 135}\, 419 (2009).\n\n[2] O.I. Ka rtavtsev\, A.V.Malykh\, to be published.\n\n[3] G. D. Maluzhinetz\, Dokl. Akad. Nauk SSSR {\\bf 121}\, 436--439 (1958).\n\n[4] X. Zhang\, Sh. Tan\, Phys. Rev. A {\\bf 113}\, 043312 (2026).\n\nhttps://indico.particle.mephi. ru/event/626/contributions/6350/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6350/ END:VEVENT BEGIN:VEVENT SUMMARY:Triple angular correlations in inelastic nuclear collisions with g amma-ray emission: astrophysical aspect DTSTART;VALUE=DATE-TIME:20261028T130500Z DTEND;VALUE=DATE-TIME:20261028T132000Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6349@cern.ch DESCRIPTION:Speakers: A.L. Barabanov (National Research Center Kurchatov I nstitute\, Moscow\, Russia\; National Research Nuclear University MEPhI\, Moscow\, Russia)\nInelastic nuclear collisions accompanied by gamma emissi on from excited nuclei serve as a valuable source of information regarding nuclear reaction mechanisms and the characteristics (energy\, spin\, pari ty) of nuclear levels. Notably\, however\, gamma radiation resulting from such collisions - occurring not only on the Sun but also on other stars - can be detected on Earth (see\, e.g.\, [1]). The intensity of this radiati on allows for an assessment of the concentration and energy of the collidi ng particles within stellar atmospheres. In principle\, further informatio n regarding the fluxes of colliding particles can be obtained\, as the ene rgy (frequency) of gamma quanta emitted in a specific direction depends on the trajectories of the colliding and outgoing particles. As a step towar d acquiring such data\, the characteristics of gamma radiation emitted at various angles relative to the reaction axis in the inelastic scattering o f protons (with energies ranging from 5.44 to 25 MeV) by the ¹²C nucleus was calculated in [2] (the 2⁺ state 4.439 MeV was excited). The calcula ted gamma-line shapes (intensity versus energy) showed good agreement with the results of earlier measurements.\n\nEvident expression for the differ ential cross section of the analogous 12C(n\,n’γ) reaction—involving excitation of the same 4.439 MeV state—is presented in a recent study [3 ]\, alongside the results of measurements of this cross section. Using a m ore general approach to describing angular correlations—based on functio ns of three vectors that are independent of the choice of coordinate axes\ , as first described in [4]—we derived the double-differential cross sec tions for both the 12C(n\,n’γ) reaction and the analogous 12C(p\,p’γ ). In our view\, differential cross sections expressed in terms of such ve ctor functions are better suited for calculating gamma-line shapes. This a pproach to describing triple angular correlations can be extended to other similar reactions\, including those of astrophysical significance.\n\nRef erences\n1. D.J. Forrest\, R.J. Murphy. Solar Physics\, 1988\, v. 118\, is s. 1\, p. 123-135.\n2. J. Kiener. Phys. Rev. C\, 2019\, v. 99\, iss. 1\, 0 14605.\n3. P. Filonchik et al. Int. J. Mod. Phys. E\, 2024\, v. 33\, iss. 12\, 2441020.\n4. L.C. Biedenharn. Pure and Applied Physics\, v. 9 (Nuclea r Spectroscopy\, Edited by F.Ajzenberg-Selove)\, part B\, 1960\, section V \, subsection C\, p. 732 (Academic Press\, New York and London).\n\nhttps: //indico.particle.mephi.ru/event/626/contributions/6349/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6349/ END:VEVENT BEGIN:VEVENT SUMMARY:The Role of Rotational Dynamics of the Dinuclear System in the For mation of Fission Fragment Spins DTSTART;VALUE=DATE-TIME:20261028T135000Z DTEND;VALUE=DATE-TIME:20261028T140500Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6348@cern.ch DESCRIPTION:Speakers: Julia Shcherbina ()\nThe angular momenta acquired by fission fragments are formed already at the stage of the compact dinuclea r system. One of the sources of their excitation is collective rotational degrees of freedom associated with deviations of the fragments from the co axial configuration. However\, the transition from the collective motion o f the system to the individual angular momenta of the fragments is not una mbiguous: the result depends on the choice of coordinates used to describe the rotational motion and on which quantities are assumed to be conserved during such motion.\nThis issue is of particular importance for transvers e oscillations\, which are commonly identified with the bending degree of freedom. Geometrically\, the corresponding motion can be represented as a change in the mutual orientation of the fragments with respect to the fiss ion axis. However\, such a description alone does not determine the distri bution of angular momentum between the intrinsic rotation of the fragments and the rotation of the dinuclear system as a whole. This ambiguity leads to different effective moments of inertia used in fission models [1–4]. \nIf the transverse motion is treated as an independent relative degree of freedom\, conservation of the total angular momentum implies opposite dir ections of rotation of the fragments. The energy of such motion is charact erized by the reduced moment of inertia constructed from the moments of in ertia of the fragments themselves [1\,2]. In this case\, no additional orb ital rotation of the dinuclear system is introduced\, and the bending exci tation is directly associated with oppositely directed angular momenta of the fragments.\nAn alternative approach to constructing the rotational deg ree of freedom arises when oscillations about the equilibrium rotational s tate of the dinuclear system are considered [3\,4]. In this case\, a chang e in the orientation of one of the fragments is accompanied by a rearrange ment of the motion of the entire system. Consequently\, part of the angula r momentum associated with the excitation of the transverse motion is orbi tal. Depending on the scheme adopted\, the rotation of either the light or the heavy fragment may be considered\, compensated by a rotation of the r emaining system.\nFrom a physical point of view\, this means that the same term\, bending mode\, may be used for motions having different angular-mo mentum structures. In the first case\, the motion corresponds to pure rela tive rotation of the fragments\, whereas in the second case\, the excited degree of freedom contains an additional collective component. Therefore\, a direct comparison of the results of different models based solely on th e magnitude of the effective moment of inertia may be inappropriate. For t he schemes considered in [3\,4]\, it appears appropriate to use the term p seudo-bending motion\, since the corresponding description includes a chan ge in the orbital angular momentum.\nThis distinction manifests itself dir ectly in the transition from collective dynamics to the observable spins o f the fission fragments. In the statistical description of rotational degr ees of freedom\, the mean-square angular momentum is determined by the eff ective moment of inertia and the excitation temperature. Consequently\, a change in the mechanical model of the bending motion\, while keeping the o ther parameters of the system unchanged\, leads to a change in the predict ed fragment spins. At temperatures of the order of 1–2 MeV\, the contrib ution of the considered degree of freedom may reach several units of ℏ\, making it comparable with characteristic fragment-spin values.\nIn the pr esent work\, a systematic comparison of the effects of different descripti ons of the rotational dynamics on the angular characteristics of fission p roducts is performed. Within the framework of the cold-fission model\, the reactions 238U(n\,f) and 232Th(n\,f)\, as well as the spontaneous fission of 252Cf\, are considered. Different prescriptions for the moments of ine rtia of the fragments\, corresponding to the hydrodynamic and superfluid l imits\, are employed. For each case\, the quantities determining the forma tion of fragment spins and orbital angular momenta\, as well as their corr elations\, are calculated.\nThe obtained results are compared with the cal culations and experimental data presented in [5]. The analysis makes it po ssible to assess the extent to which the predictions of spin characteristi cs are determined by the properties of the fragments themselves and the ex tent to which they depend on the adopted description of the collective rot ational degree of freedom. It is shown that the choice of the effective mo ment of inertia of the bending motion is not merely a formal element of th e model and can lead to significant changes in the quantitative characteri stics of the angular momenta of the fission fragments.\nReferences\n J. Ra ndrup\, R. Vogt\, Phys. Rev. C 89\, 044601 (2014).\n J. R. Nix\, W. J. Swi atecki\, Nucl. Phys. 71\, 1 (1965).\n J. Randrup\, T. Døssing\, R. Vogt\, Phys. Rev. C 106\, 014609 (2022).\n T. M. Shneidman et al.\, Phys. Rev. C 65\, 064302 (2002).\n J. N. Wilson et al.\, Nature 590\, 566 (2021).\n\nh ttps://indico.particle.mephi.ru/event/626/contributions/6348/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6348/ END:VEVENT BEGIN:VEVENT SUMMARY:Single particle nucleon energies of selected nuclei based on modif ied folded Yukawa potential DTSTART;VALUE=DATE-TIME:20261028T140500Z DTEND;VALUE=DATE-TIME:20261028T142000Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6347@cern.ch DESCRIPTION:Speakers: Dmitrij Sitkov ()\nThere exist a number of models fo r nuclear structures allowing for descriptions of various nuclear properti es [1]. One of such models is based on the idea of nucleons inside a give n nucleus lying in the folded Yukawa potential\, accounting for the spin-o rbit and the Coulomb interactions [2\, 3]. The model can be adapted for d ifferent nuclei properties calculations [4].\n\nThe work presents calcula ted single particle nucleon energies of selected nuclei based on spherical ly symmetrical shape approximation for modified folded Yukawa potential. T he proposed modification provides for a way of taking possible metastable single particle levels into account. Obtained energy levels are suitable t o be used in combinatorial approaches of calculating level density of exci ted states of a nucleus in the frozen core approximation.\n\n 1. *Ring P* .\, *Schuck P*. The Nuclear Many-Body Problem. — New York : Springer \, 1980. — (Texts and Monographs in Physics).\n 2. *Bolsterli M*.\, *F iset E*. *O*.\, *Nix J*. *R*.\, *Norton J*. *L*. New Calculation of Fission Barriers for Heavy and Superheavy Nuclei // Physical Review C.  — 1972. — v. 5\, iss. 3. — p. 1050–1077.\n 3. *Nix J*. *R*. Calculation of Fission Barriers for Heavy and Superheavy Nuclei // Annua l Review of Nuclear Science. — 1972. — v. 22\, iss. 1. — p. 65 –120.\n 4. *Uhrenholt H*.\, *Åberg S*.\, *Dobrowolski A*.\, *Døssin g T*.\, *Ichikawa T*.\, *Möller P*. Combinatorial nuclear level-densit y model // Nuclear Physics A. — 2013. — v. 913. — p. 127–156 .\n\nhttps://indico.particle.mephi.ru/event/626/contributions/6347/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6347/ END:VEVENT BEGIN:VEVENT SUMMARY:Creation of transuraniums in experimental prompt r-process and inv erse task of the neutron fluence DTSTART;VALUE=DATE-TIME:20261028T132000Z DTEND;VALUE=DATE-TIME:20261028T133500Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6346@cern.ch DESCRIPTION:Speakers: Vladimir Lyashuk (The Institute for Nuclear Research of the Russian Academy of Sciences\, Moscow\, 117312 Russia )\nCreation o f transuranic nuclides in experimental pulsed neutron fluxes of high inten sity (up to 10E+30 – 10E+31 n/cm2) is investigated in the kinetic model of the astrophysical r-process. The dynamics of the rapid nucleosynthesis (in the interval ~10E-6 s) is introduced when the process temperature decr eases and is taken into account by correction of the cross sections at rad iation capture of neutrons. In spite of the more lower fluxes and temperat ure compare to possible cosmological sites of superheavy isotope productio n (up tp 10E+40 n/cm2 and ~10E+9 K in case of binary star mergers\, stri pping matter in massive binary systems) an application of heavy (actinides ) targets allows to ensure production of identifiable quantities of transu raniums up to 257Fm by multiple neutron capture (up to 19 neutrons for 238 U targets). Subsequent correction of transuranium outputs after pulse term ination is taken into account in beta-decays of neutron-excess nuclei.\n\n The produced analytical analysis strongly indicated on the roughly linear dependence of the relation of isotope yields on the pulse neutron fluence. Agreement of calculated isotope relations with experiments is a criterion of possible fluence. Evaluation of the realized neutron fluence is the i nverse problem. The task of yields modeling of neutron-rich isotopes (and inverse problem of the achieved fluence) during multiple neutron captures is solved in the developed ABM model\, which takes into account the drop o f the temperature during the expansion of matter with a linear velocity ~1 90 km/s. The model allowed to obtain good or satisfactory agreement with p ublished US-experiment for pulse production of transuranic elements. In th e simulation it was applied the 238U\, 238Pa and 243Am targets according t o declared results of the tests. It was proposed an algorithm for calculat ing dependence of isotope relations on fluence for complex targets. It was evaluated achieved fluences and obtained good agreement in isotope relati on of seven large scale experiments.\n\n[1] G. I. Bell. Phys. Rev. 139\, B 1207 (1965)..\n\n[2] J. S. Ingley\, Nucl. Phys. A 124\, (1969) 130 (1969). \n\n[3] V. I. Zagrebaev\, A. V. Karpov\, I. N. Mishustin\, and W. Greiner\ , Phys. Rev. C 84\, (2011) 044617.\n\n[4] Yu. S. Lutostansky\, and V. I. L yashuk. Phys. At. Nucl. 88\, 16 (2025)..\n\n[5] V. I. Lyashuk\, Results in Physics. Volume 56\, (2024) 107234.\n\n[6] V. I. Lyashuk\, Physics of Par ticles and Nuclei Letters\, 2025\, Vol. 22\, No. 2\, (2025) 324.\n\nhttps ://indico.particle.mephi.ru/event/626/contributions/6346/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6346/ END:VEVENT BEGIN:VEVENT SUMMARY:The nature of isotopic anomalies in charge radii and atomic isomer shifts at N=126 region. DTSTART;VALUE=DATE-TIME:20261028T125000Z DTEND;VALUE=DATE-TIME:20261028T130500Z DTSTAMP;VALUE=DATE-TIME:20261027T035312Z UID:indico-contribution-324-6345@cern.ch DESCRIPTION:Speakers: Ivan Borzov (National Research Centre "Kurchatov Ins titute")\nThe nature of isotopic anomalies in charge radii and atomic isom er shifts \nat N=126 region.\n\nI.N. Borzov\, 1\, 2\, S.S. Pankratov\, 1\, 3\n1) National Research Centre”Kurchatov Institute”\, Moscow\, Russia \n2) Bogolubov Laboratory of Theoretical Physics\, JINR\, Dubna\, Russia \ n3) Moscow Institute of Physics and Technology\, Dolgoprydny\, Russia\n\nT he nuclear charge ms-radii and atomic isomer shift for the 211-219Bi isoto pes are calculated within the self-consistent finite Fermi systems theory using the Fayans functional FaNDF0. A special attention is paid to the ano malous part of the functional. In contrast to our previous calculations [1 ]\, the full Hartree-Fock-Bogolubov (HFB) formalism is employed with the n on-diagonal pairing.\n The main impact on the kink in the isotopic depen dence of radii at N=126\, as well as on the isomer shifts comes from the o ccupancy factors of the neutron discrete and continuum quasiparticle state s with principal quantum number n = 1\, as well as the neutron pairing con tribution to the proton central mean field potential. In contrast\, in th e RMF framework [2] the kink is determined exclusively by the contribution of the ν1i11/2 orbital assuming it is inverted with respect to the ν2g9 /2 orbital which is not supported by the experiment. Importantly\, our cal culations successfully describe the unexpected negative isomer shift in 21 5Bi observed recently at ISOLDE (CERN) [3].\n\n1. I.N. Borzov\, S.V. Tolok onnikov\, Physics of Atomic Nuclei 87\, 423 (2024).\n2. U. C. Perera \, A. V. Afanasjev\, and P. Ring. Phys.Rev. C 104\, 064313 (2021).\n3. M.D. Sel iverstov\, A. Barzakh\, D. Fedorov\, P. Molkanov\, and V. Panteleev\, \nPr oceedings of the XXIV International Conference “Nucleus -2024”\, 1–5 July (Dubna\, 2024).\n\nhttps://indico.particle.mephi.ru/event/626/contri butions/6345/ LOCATION: Conference Hall 1 URL:https://indico.particle.mephi.ru/event/626/contributions/6345/ END:VEVENT END:VCALENDAR