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Italy-Japan Symposium on Joint Activities in Fundamental Physics - 日伊基礎物理学共同研究活動シンポジウム
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Europe/Rome
Kore University of Enna
Kore University of Enna
Polo scientifico/tecnologico Santa Panasia
Aurora Tumino
(Istituto Nazionale di Fisica Nucleare),
Marco La Cognata
(Istituto Nazionale di Fisica Nucleare)
Description
We are delighted to announce the Italy-Japan Symposium dedicated to celebrating and revitalizing the historical collaboration between Italy and Japan in the fields of nuclear physics, nuclear astrophysics, and particle physics.
This meeting will serve as a platform to honor our shared past, showcase ongoing research, and, most importantly, discuss and plan future joint activities. It is an opportunity to strengthen existing bonds and forge new collaborations that will push the boundaries of fundamental physics.
The Symposium brings together key diplomatic, institutional, and scientific figures, highlighting the strong ties between our nations. The event sees the participation of Dr. Masahiro Nakade (First Secretary and Scientific Attaché) and Hiroshi Kubo (Culture and Press Office) from the Embassy of Japan in Italy, alongside academic and local leadership including Prof. Cataldo Salerno (President of Kore University of Enna), Prof. Francesco Castelli (Pro-rector of Kore University), Dr. Maurizio Dipietro (Mayor of Enna), Avv. Antonio Cammarata (Mayor of Piazza Armerina), and Dr. Carmelo Nicotra (Director of Villa Romana del Casale).
The scientific program is further enriched by senior leadership from INFN—including CSN3 President Dr. Paolo Giubellino, and Laboratori Nazionali del Sud Director Dr. Santo Gammino—with key contributions from Prof. Kouichi Hagino (Kyoto University) and Prof. Atsushi Tamii (RCNP, Osaka University). This collaborative environment provides an excellent opportunity to engage with the figures shaping bilateral cooperation in physics throughout the technical sessions.
Please be aware that the Symposium organization has not authorized any agency—such as Global Travel Team—to handle travel or accommodation bookings on behalf of participants.
The symposium is organized under the patronage of the Embassy of Japan in Italy, as a celebratory event marking the 160th anniversary of diplomatic relations between Italy and Japan and with the patronage of Comune di Enna and Parco Archeologico della Villa Romana del Casale.
Participants
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Opening SessionConveners: Aurora Tumino (UKE & INFN-LNS), Marco La Cognata (INFN-LNS)
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1
WelcomeSpeakers: Prof. Cataldo Salerno (President of Kore University of Enna), Prof. Francesco Castelli (Pro-rector of Kore University of Enna), Dr Maurizio Dipietro (Mayor of Enna), Avv. Antonio Cammarata (Mayor of Piazza Armerina), Dr Carmelo Nicotra (Director of Villa Romana del Casale), Dr Santo Gammino (Director of INFN-LNS), Dr Paolo Giubellino (President of CSN3 INFN), Prof. Kouichi Hagino (Kyoto University), Prof. Atsushi Tamii (Research Center for Nuclear Physics, the University of Osaka)
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Session 1Convener: Paolo Giubellino (Istituto Nazionale di Fisica Nucleare)
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PANDORA: a new experimental setup for measuring in-plasma nuclear β-decays
The abundance of elements in the Cosmos is currently a topic of active investigation. Since the dawn of nuclear astrophysics, various processes have been identified to explain the synthesis of elements, as the slow (s-) and rapid (r-) neutron capture processes providing 99% of elements beyond the iron peak. Nucleosynthesis models are sensitive to a variety of inputs, such as neutron capture cross sections and β-decay rates. Both theory [1,2] and experiments on fully stripped ions [3] have shown that β-decay lifetimes can change of even orders of magnitude in ionized matter. The PANDORA (Plasmas for Astrophysics, Nuclear Decay Observation and Radiation for Archaeometry) project [4] aims at building a new experimental facility, at INFN-LNS Catania, for probing for the first time the nuclear β-decay rates in hot plasmas. In this facility the plasma will mimic some thermodynamical stellar conditions, especially in terms of temperature. The setup consists of a compact, superconducting B-minimum magnetic trap, where plasmas of various elements can be generated via Electron Cyclotron Resonance and reach densities ne~10^11-10^13 cm^-3, with a “tunable” temperature in the range Te~0.1-30 keV. 14 HpGe detectors will be used for measuring the decay rates, counting the gammas emitted by the de-excitation of the daughter nuclei. The number of decays per time-unit will be monitored simultaneously to the measurement of thermodynamical plasma parameters, achieved by a multi-diagnostic system (RF interferometers and polarimeters, optical and X-ray spectroscopy, X-ray imaging and space resolved spectroscopy). The facility is now under construction, and first plasma is expected in 2026. The setup enables other astrophysically relevant experiments, such as optical opacities determination that are relevant for the r-process nucleosynthesis in a kilonova scenario. Over a list of more than one hundreds potential physics cases, the first measurements will focus on a shortlist consisting in 94Nb (t1/2 ~ 2 x10^4 y), 134Cs (t1/2 ~ 2,5 y), 176Lu (t1/2 ~ 3.76x10^10). Meanwhile the construction is progressing, the collaboration has developed a generalized theory of β-decay in LTE and nLTE plasmas, benchmarking models predictions with 7Be, 140Pr, 163Dy, in H- or He-like configurations which have been measured in Storage Ring experiments at GSI.
[1] K. Takahashi and K. Yokoi, Nuclear β-decays of highly ionized heavy atoms in stellar interiors. Nuclear Physics A 404(3):578-598 · August 1983. DOI: 10.1016/0375-9474(83)90277-4
[2] K. Takahashi and K. Yokoi, Beta-decay rates of highly ionized heavy atoms in stellar interiors, Atomic Data and Nuclear Data Tables. Volume 36, Issue 3, May 1987, Pages 375-409 DOI: https://doi.org/10.1016/0092-640X(87)90010-6
[3] Y. A. Litvinov and F. Bosch, Beta decay of highly charged ions 2011 Rep. Prog. Phys. 74 016301
[4] D. Mascali et al. PANDORA, a new facility for interdisciplinary in-plasma physics. European Physical Journal A 03/2017; 53(7)., DOI:10.1140/epja/i2017-12335-1Speaker: Dr David Mascali (LNS) -
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Recent studies within the realistic shell model, focusing on first-forbidden beta decays and ordinary muon captureSpeaker: Giovanni De Gregorio (Istituto Nazionale di Fisica Nucleare)
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2
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11:00
Break
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Session 2Convener: Faical Azaiez (Istituto Nazionale di Fisica Nucleare)
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The GAMMA spectroscopy group activities between Italy and Japan
The GAMMA collaboration collects the Italian community devoted to experimental studies of nuclear structures by means of gamma-spectroscopy techniques.
In this talk the activities of the GAMMA group will be presented, highlighting the campaigns at Japanese research centers, such as Osaka and Riken.Speaker: Giovanna Benzoni (Istituto Nazionale di Fisica Nucleare) -
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Current status of systematic ISGMR measurements using an active target CAT-M
The nuclear matter equation of state (EOS) is fundamental to understanding not only the bulk properties and structure of atomic nuclei but also various astrophysical phenomena, including neutron star mergers and supernova explosions.
The isoscalar giant monopole resonance (ISGMR) provides a direct constraint on the incompressibility of nuclear matter. In particular, the isospin-dependent term of the incompressibility, $K_\tau$, can be extracted from the centroid energies of the ISGMR. Previous experimental studies on stable Sn and Cd isotopes have reported values of $K_\tau$; however, the uncertainty remains large of about 100 MeV. Therefore, systematic ISGMR measurements including unstable nuclei, are required to improve the precision of $K_\tau$.
To enable systematic measurements, we have developed an active target system, CAT-M, designed for use with heavy-ion beams. As a first step toward systematic studies, ISGMR measurements were performed for Kr and Xe isotopes at the Heavy Ion Medical Accelerator in Chiba (HIMAC). A deuterium gas at a pressure of 40 kPa was used as the active target, and deuteron inelastic scattering was measured in inverse kinematics.
The CAT-M system consists of a Beam TPC, a Recoil TPC, silicon strip detectors (SSDs), and a dipole magnet. The trajectories of incoming beam particles were measured using the Beam TPC, while recoil particles were detected by the Recoil TPC and SSDs, performing track reconstruction. The reaction were reconstructed using the missing-mass spectroscopy. A multipole decomposition analysis was then performed, successfully extracting the ISGMR strength distribution. As a result, the centroid energy of the ISGMR in $^{86}$Kr was determined to be $17 \pm 1$ MeV. These results demonstrate the capability of the CAT-M for systematic ISGMR measurements including unstable nuclei.
In this presentation, we will report the result of $^{86}$Kr and current status of the systematic measurements, and discuss future prospects.
Speaker: Fumitaka ENDO (RIKEN Nishina Center) -
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Experimental Investigation of the 6He + p Reaction: Elastic Scattering and Two-Neutron TransferSpeaker: Fulong Liu
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Gamma-ray spectroscopy at LNL and possible synergiesSpeaker: Andrea Gottardo (Istituto Nazionale di Fisica Nucleare)
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4
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13:00
Lunch
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Session 3Convener: Kouichi Hagino (Kyoto University)
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A few avenues in the search for improved nuclear Energy Density Functionals
In this contribution, I will review some recent progress in nuclear Density Functional Theory (DFT), mainly carried out within our group and/or with emphasis on the collaboration with Japan.
The three main topics that will be discussed will be (i) DFT-based models for an accurate description of excited states, (ii) Bayesian inference of the Energy Density Functional (EDF) parameters, (iii) perspectives for an ab initio-based DFT. If time allows, a brief account will be given about a new direction, that is, orbital-free DFT (OF-DFT).Speaker: Gianluca Colo' (Istituto Nazionale di Fisica Nucleare) -
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What do the Q moments in Cd isotopes indicate?
The quadrupole moments in the first 11/2- states in Cd isotopes are systematically measured from N=63 to N=81 (D. T. Yordanov et al., Phys. Rev. Lett. 110, 192501 (2013)), presenting a very clear linear increase from negative to positive values. Since this linearity well follows what the single-j shell model with the pairing force provides analytically, it is interpreted as a manifestation of the success of the single-j shell model.
In this study, we have carried out large-scale shell-model calculations to verify this conventional interpretation. With the valence shell consisting of the proton p1/2-g9/2 and the neutron d5/2-g7/2-h11/2-s1/2-d3/2 orbitals, and the effective interaction composed of the G matrix and an empirical interaction, we have successfully reproduced the trend of 2+ and 4+ energies in even-A Cd isotopes and the quadrupole and magnetic moments in odd-A Cd isotopes. By analyzing the wave functions, the first 11/2- levels in Cd isotopes are not dominated by the lowest seniority (v=1), thus contradicting to the conventional interpretation.
A natural question then arises: why are the observed quadrupole moments reproduced with the wave functions different from those of the seniority scheme? To answer this question, we examined deformation in Cd isotopes with the parity-projected Hartree-Fock calculations in the shell-model space, finding the dominance of prolate deformation throughout the isotopes chain. Based on those results, we propose that the change of the quadrupole moments in Cd isotopes is caused by the increasing K number with neutron number. This interpretation seems to be in good accordance with the calculated B(E2) systematics and the measured quadrupole moments in the 2+ states.
Speaker: Yutaka Utsuno (Japan Atomic Energy Agency) -
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Double Gamow-Teller resonance
Double Gamow–Teller (DGT) transition is a nuclear process in which both the spin and isospin are flipped twice without a change in the orbital angular momentum. The high excitation energy region of the DGT transition is hardly known. Especially, the giant resonance in the DGT transition, double Gamow–Teller giant resonance (DGTGR), is expected to exist, but there has not been the established observation. The observation on the DGTGR will open up the new domain of the nuclear mode, as well as its observables will provide information on the nuclear matrix element of the neutrino-less double beta decay.
We have performed the experiment of the ($^{12}$C, $^{12}$Be(0$^{+}_{2})$) for 48Ca target at RIBF, aiming at the observation of the DGTGR. We used the intense primary beam of $^{12}$C with an energy of 250 MeV/nucleon provided from Superconducting Ring Cyclotron and used BigRIPS as a spectrometer. As $^{12}$Be(0$^{+}_{2}$) decays with emitting $e^{+}e^{-}$ pair, we identified the reaction channel by detecting the 511-keV gamma ray using DALI2. The cross section in the energy region of 0 to more than 30 MeV was measured with the energy resolution of 1.5 MeV and the angular resolution of 0.2$^{\circ}$, and we observed a forward peaking structure around 20 MeV in the excitation energy of $^{48}$Ti. We conclude that it is the candidate for the DGTGR. The DGT transition strength B(DGT) was also evaluated from the observed cross section by performing the multipole decomposed analysis. This first result of the B(DGT) in the high energy region has large uncertainty because of the lack of statistics, but it had established the way to obtain the information on the DGTGR experimentally.
The outline of the experiment and the prospects will be given in the talk.Speaker: Akane Sakaue (The University of Osaka)
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16:00
Guided tour of Enna historical center
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Session 4Convener: Angela Bracco (Istituto Nazionale di Fisica Nucleare)
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Uncovering the mechanism of chiral three-nucleon force in driving spin–orbit splitting
We clarify the relationship between spin–orbit (SO) splitting and three-nucleon forces (3NFs) derived from chiral effective field theory. While the influence of 3NFs on enhancing SO splitting is well known, the mechanisms underlying this enhancement have remained elusive. Through the irreducible tensor decomposition of the chiral 3NF, our investigation reveals that the rank-1 tensor component of the 3NF contributes primarily to the SO splitting in light nuclei as well as medium-heavy nuclei.
We also discuss the antisymmetric nature of the rank-1 3NF, which is akin to the Dzyaloshinsky–Moriya interaction causing the spin canting in magnetic ions.
Speaker: Tokuro Fukui (Kyushu University) -
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¹²C, ¹⁶O and their production reactions in near-zero-range Effective Field Theory
The synthesis of carbon and oxygen plays a central role in nuclear astrophysics, as the reactions 3α → ¹²C + γ and ¹²C(α,γ)¹⁶O govern the stellar C/O ratio and influence stellar evolution and nucleosynthesis. Despite their importance, a consistent theoretical description of these processes at low energies remains challenging due to strong Coulomb effects. In this talk, I present a near-zero-range Effective Field Theory (EFT) approach tailored to α-cluster systems, exploiting the separation of scales between the internal excitation of the α particle and the low-energy dynamics of cluster degrees of freedom. Two-body α–α interactions are constructed up to next-to-next-to-leading order and constrained by low-energy scattering data and the properties of the ⁸Be resonance. Three- and four-body contact interactions are then introduced to reproduce the bound and excited states of ¹²C and ¹⁶O. Within this framework, preliminary results are shown for the triple-α capture process as well as for the radiative capture reaction ¹²C(α,γ)¹⁶O. Calculated cross sections, reaction rates, and low-energy astrophysical S factors are discussed and compared with available experimental data and existing theoretical approaches. Ongoing developments aim at improving the quantitative accuracy of the method and at providing a unified EFT description of carbon and oxygen production in stellar environments.
Speaker: Elena Filandri (ECT*) -
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Heavy-ion fusion reactions at deep subbarrier energies
It has been well known that nuclear collective excitations significantly affect heavy-ion reactions at energies around the Coulomb barrier. A prominent example is the large enhancement of fusion cross sections at subbarrier energies. To account for such enhancement, the coupled-channels approach has been widely employed.
While the coupled-channels approach has been successful in reproducing fusion cross sections at subbarrier energies, recent experimental evidence demonstrates that it significantly overestimates fusion cross sections at deep subbarrier energies. This phenomenon, referred to as fusion hindrance, was first identified in the 60Ni+89Y system. Subsequently similar behaviour has been observed in several other medium-heavy systems, such as 64Ni+64Ni. However, it remains unclear to what extent fusion hindrance occurs in lighter systems, such as 12C+12C, which are of critical importance to nuclear astrophysics.
In this contribution, I will discuss recent developments in physics of heavy-ion fusion reactions at deep subbarrier energies. I will first review recent measurements of fusion cross sections at deep subbarrier energies for medium-light systems, such as 12C+24Mg, conducted by the Legnaro group (Alberto Stefanini and Giovanna Montagnoli, et al.). I will then present our recent reanalysis of fusion cross sections for the 12C+12,13C systems and discuss the presence or absence of the fusion hindrance phenomenon in these systems.
Speaker: Kouichi Hagino (Kyoto University) -
14
Microscopic Description of Low-Energy ¹²C+¹²C Fusion Reaction
The ¹²C+¹²C fusion reaction plays essential roles in various astrophysical phenomena, including carbon burning in massive stars, Type Ia supernova ignition, and X-ray superbursts. However, its reaction rate at low temperatures remains highly uncertain due to difficulties in direct measurements. In this talk, we discuss our recent microscopic studies of the ¹²C+¹²C fusion reaction based on antisymmetrized molecular dynamics (AMD) and generator coordinate method (GCM) calculations employing several nuclear energy‑density functionals. This fully microscopic model describes multi-nucleon rearrangement, channel coupling, and nuclear deformation without adjustable parameters.
Our AMD approach successfully reproduces cross sections above the Gamow window of X-ray superbursts. It predicts several 0⁺ and 2⁺ molecular resonances within the Gamow window, resulting in pronounced S‑factor peaks without showing low‑energy hindrance. We systematically investigate the dependence of resonance properties and reaction rates on different density functionals. Gogny functionals predict strong low-energy resonances that enhance the reaction rate, whereas Skyrme functionals yield weaker low‑energy structures, leading to reaction rates closer to the hindrance model.
We will also discuss future directions to reduce these uncertainties. A key step is the experimental identification of deep sub‑barrier 0⁺ and 2⁺ molecular resonances. Our calculations predict enhanced isoscalar monopole and quadrupole strengths, indicating that α‑inelastic scattering on ²⁴Mg is a promising probe that can bypass the Coulomb barrier. It is expected to significantly reduce the uncertainty in the ¹²C+¹²C reaction rate and improve simulations of stellar explosions.Speaker: Dr Yasutaka TANIGUCHI (Fukuyama University) -
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Proton elastic scattering measurement from 132Sn to extract the matter radiusSpeaker: Yuto Hijikata (RIKEN Nishina Center)
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11
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11:00
Break
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Session 5Convener: Nobu Imai
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Distinctive Features and Research Strengths of the JAEA Tokai Tandem Accelerator
The JAEA Tokai Tandem Accelerator, at the Japan Atomic Energy Agency (JAEA), is one of the largest electrostatic accelerators in the world, with a maximum accelerating voltage of 20 MV. It has been in continuous operation since 1982.
In general, the advantages of a tandem accelerator include ion-species versatility, adjustable accelerating voltage, continuous beam operation, a small beam spot size, and a narrow energy spread. At the Tokai Tandem Accelerator, these advantages are further enhanced by the electron cyclotron resonance ion source (ECRIS) and by the experimental environment that allows the use of radioactive targets.
The ECRIS is installed in the high-voltage terminal and enables single-ended acceleration using positive ions, thereby realizing the acceleration of ion beams with high charge states and high beam currents. The ECRIS can provide noble-gas ions, molecular ions, as well as several metallic ions. Furthermore, because charge-state conversion is not required in single-ended acceleration, rapid changes in ion-beam energy are possible.
Such rapid adjustment of the accelerating voltage facilitates the acquisition of excitation functions and depth profiling of hydrogen using nuclear reaction analysis (NRA).Another rare feature of the Tokai Tandem facility is the possibility to irradiate radioactive targets on several licensed beamlines. This, coupled to the ~1 mm beam spot size, enables meaningful experiments with extremely small target quantities, including radioactive targets such as ²⁵⁴Es at the 10 ng level.
In this symposium, we present these distinctive features of the Tokai Tandem Accelerator, together with recent trends in its utilization and future prospects.
Speaker: Takuhiro Asozu (Department of Research Infrastructure Technology Development, JAEA) - 17
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Spectroscopy of heavy actinide nuclei at the JAEA Tandem accelerator: investigating deformation and magicity in the A~252 region
The existence of long-lived super heavy elements depends on the presence of shell gaps that increase nuclear stability against fission. The "Island of Stability" (IoS) is predicted to have the largest gaps, specifically around atoms with proton number Z=114, 120 and neutron number N=184. Small energy gaps occurring near Z=100,108 and N=152,162 also enhance the stability of heavy actinides and trans-actinides, creating a sort of "submerged rift" leading to the IoS. The structure properties of actinides near these deformed shell gaps provide imporant benchmarks for theoretical models on superheavy elements and the IoS.
At the JAEA Tandem we used gamma-ray spectroscopy to study the structure of actinides near $^{252}$Fm. Recent results, which include new information on K isomers in $^{248}$Cf (Z=98,N=150)[1] and the ground state rotational band and moment of inertia of 252Fm, will be presented.
One experimental factor that limits the study of heavy actinides is the low detection efficiency for low-energy transitions (<60 keV), which are typical of rotational bands in this region. A possible solution, provided by a new array of CdTe detectors that we are currently develping, will also be discussed.
[1] R. Orlandi et al.. Phys. Rev C 106, 064301 (2022).
[2] R. Orlandi et al., Submitted for publication.Speaker: Riccardo Orlandi (Advanced Science Research Center, JAEA)
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13:00
Lunch
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Session 6Convener: Tokuro Fukui (Kyushu University)
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Outputs and perspectives with decelerated RI beams using OEDOSpeaker: Nobu Imai
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Density functional approach to low-energy radiative neutron capture reaction on very neutron rich-nuclei
The r-process, competing reactions of beta-decay and radiative neutron capture, takes place in neutron-rich nuclei with small neutron separation energy, typically around 2MeV. We shall describe the neutron capture reaction by means of the nuclear density functional theory, and predict a new mechanism in which roles are played by low-lying collective excitations specific to neutron-rich nuclei, such as the pygmy quadrupole mode and the octupole vibrations as well as the quasiparticle resonance caused by the pair correlation.
The theoretical method is based on the continuum quasiparticle random phase approximation where the neutron scattering state and collective excitations as well as the gamma transitions are described in the same framework. It provides a scheme where the collectivity and the pair correlation are taken into account in the capture process. We demonstrate the method with numerical calculation using the Skyrme density functional model with the density dependent delta pairing interaction. As an example we describe 89Ge(n,g)90Ge where the pygmy quadrupole mode forms a resonance capture, and 91Zn(n,g)92Zn where the quasiparticle resonance contributes to the low-energy s-wave capture cross section.T. Saito and M. Matsuo, Phys. Rev. C 104, 034305 (2021)
T. Saito and M. Matsuo, Phys. Rev. C 107, 064607 (2023)
T. Saito and M. Matsuo, arXiv: 2504.18239Speaker: Masayuki Matsuo (Niigata U. / RCNP Osaka U.) -
21
Isospin symmetry breaking based on nuclear density functional theory
The isospin symmetry breaking part of the nuclear interaction is a small part of the whole; however, it sometimes gives important contributions to nuclear properties, such as the difference of mirror nuclei, the isobaric analog states, and the neutron-skin thickness. The isospin symmetry breaking terms also affect the estimation of the slope parameter of the nuclear symmetry energy.
In this talk, I will first summarize our recent study on the isospin symmetry breaking in nuclear properties and point out the lack of precise determination of the effective nuclear interaction or energy density functional for the isospin symmetry breaking terms. Then, I will introduce our recent attempt to determine the energy density functional of the isospin symmetry breaking terms. Finally, I will present some future perspectives.Speaker: Dr Tomoya Naito (The University of Tokyo) -
22
High-precision atomic mass measurements using multi-reflection time-of-flight (MRTOF) mass spectrograph at RIKEN RIBF
Precision atomic mass measurements are of great importance throughout nuclear physics. Within RIKEN's RIBF, we perform high-precision atomic mass measurements at three multi-reflection time-of-flight mass spectrographs with two more coming soon. These will allow us to cover the full range of nuclides, from the light halo nuclei to the superheavy elements. In addition to mass measurements, we have devised detectors to allow simultaneous and correlated decay spectroscopy as well.
Better understanding of the forces which bind the heaviest elements can be achieved through precision determination of atomic masses, as such measurements provide direct insight to the nuclear binding energy. This can provide insight into the upper bounds of nuclides, the existence and location of the predicted "island of stability", and the mass flow at the upper reaches of the rapid neutron capture process via fission recycling. To perform meaningfully precise atomic mass measurements of such nuclides requires a method which can achieve high resolving power, is amenable to extremely low yields, and can tolerate a large relative rate of contaminants. Multi-reflection time-of-flight mass spectrometry is one such method, as it offers resolving powers approaching 10^6 while not only tolerating a reasonably high contaminant rate but utilizing contaminants as reference ions when possible. The technique also allows the use of combined spectroscopy by adding decay detectors to the ion implantation detector used for time-of-flight determination. In this way low-yield radioactive ions typical in superheavy nuclide research can be confirmed via decay spectroscopy to facilitate measurements with very low total counts. We will describe results and future plans for such measurements at both the SHE-Mass and KISS-1.5 facilities located within the RIKEN Nishina Center.
To fully understand the rapid neutron capture process, the masses and lifetimes of neutron-rich nuclides is vital. At the end of the ZeroDegree beam line we have implemented a gas cell and MRTOF along with a host of decay detectors. This allows for simultaneously performing in-beam gamma-ray spectroscopy, precision atomic mass measurements, and decay studies of the neutron-rich nuclides. A planned upgrade of the gas stopping cell, along with development of a second gas stopping cell and MRTOF for installation at a highly dispersive position in the BigRIPS beam line (SLOWRI), will allow access to even more neutron-rich species as well as light species such as $^{14}$Be and $^{19}$B in the coming years. We will also discuss recent measurements from the ZeroDegree MRTOF, planned upgrades of ZeroDegree end station, and the also touch on plans for the full SLOWRI MRTOF measurements station.
Speaker: Peter Schury (KEK/IPNS Wako Nuclear Science Center)
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15:45
Group Photo
A commemorative photo will be taken
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16:15
Excursion to the Roman Villa and Gala Dinner
https://www.villaromanadelcasale.it
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Session 7Convener: Alessandro Feliciello (Istituto Nazionale di Fisica Nucleare)
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23
Hypernuclear physics at J-PARC
The Japan-Italy collaboration in hypernuclear physics has a long history since the 1990s at DAΦNE (FINUDA experiment) and then at J-PARC.
At J-PARC, we have studied spectroscopic studies of Ξ hypernuclei with the (K-,K+) reaction (E05) as well as neutron-rich Λ hypernuclei with the (π-,K+) reaction (E10), employing magnetic spectrometers at the K1.8 beam line. A missing mass spectrum for 12ΞB was obtained, indicating existence of Ξ hypernuclear bound states. Recently, a new experiment (E70) with an updated spectrometer has been also conducted.
In addition, structure of Λ hypernuclei has been also investigated via γ-ray spectroscopy at J-PARC. In particular, a γ-ray transition in 4ΛHe has confirmed a large charge symmetry breaking in Λ hypernuclei. A further experiment to precisely measure the γ-ray transition in the mirror hypernucleus, 4ΛH, is in progress.
Such spectroscopic studies of hypernuclei will provide crucial data to determine the hyperon-nucleon interactions in nuclear matter and to unveil high density matter in neutron stars.Speaker: Hirokazu Tamura -
24
The Hyper-Kamiokande Project: Preparing for Discovery
Hyper-Kamiokande is a next-generation neutrino experiment currently under construction in Japan. It will be the largest underground water Cherenkov detector ever built, with a fiducial volume eight times larger than its predecessor, Super-Kamiokande, which these days is celebrating 30 years of data taking. The inner detector will be equipped with tens of thousands of new photosensors, including 50 cm diameter PMTs and multi-PMT modules, significantly enhancing sensitivity to Cherenkov radiation in water.
The Hyper-Kamiokande observatory will investigate neutrinos from astrophysical sources, supernova burst neutrinos, supernova relic neutrinos, and rare processes such as nucleon decay. It will also serve as the far detector for a long-baseline neutrino experiment using a beam produced at the J-PARC accelerator, located 295 km away and currently used by the T2K experiment. A suite of near detectors, placed close to the accelerator, will characterize the beam and help reduce systematic uncertainties. With the upgraded 1.3 MW neutrino beam, Hyper-Kamiokande will achieve unprecedented precision in measuring neutrino oscillations, enabling the discovery of leptonic CP violation and the precise determination of atmospheric oscillation parameters.
Data taking is expected to begin in 2028. Italian contributions to Hyper-Kamiokande include key components of the far detector, such as the multi-PMT modules, front-end electronics for the 50 cm diameter PMTs, and of the near detectors. The seminar will provide an overview of the experiment, discussing its scientific goals, current status, and future outlook.
Speaker: Lucio Ludovici (Istituto Nazionale di Fisica Nucleare) -
25
Progress and future prospect on the hyperon-proton scattering experiment
The hyperon-nucleon interactions are fundamental information to describe many-body nucleon systems containing hyperons, such as hypernuclei and neutron stars.
By extending the nuclear force to baryon-baryon interactions, we also can understand the nuclear force as the interaction between quark clusters, because new aspects of baryon-baryon interaction are expected to appear especially at short the distance in hyperon-nucleon and hyperon-hyperon interactions.
Now, new attempts to describe the hyperon-nucleon interactions within the chiral effective field theory framework.
In order to make such interaction theories more realistic, more hyperon-proton scattering data are necessary.
In J-PARC, we succeeded in providing new and accurate Sigma proton scattering data for three different channels.
These new data are now used to constrain the theoretical models.
Then, we are now planning to derive differential cross sections and spin observables of Lambda proton scattering experiments at SPring-8 and J-PARC.
In addition, a collaborative work between Lattice QCD calculation and Sigma N cusp measurement is ongoing to reveal the full picture of the Lambda N interaction.
In this presentation, I will review the achievements so far and introduce the new projects to understand the LambdaN interaction.Speaker: Koji Miwa -
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The hyperon-nucleon interaction in low-energy effective field theory
In recent years, there has been a notable interest in investigating hypernuclear systems, which pro- vide a unique laboratory for studying strong interactions in the strange quark sector. One of the main applications is related to the so-called “hyperon puzzle” in neutron stars, where theoretical models including hyperons predict maximum masses of ∼ 1.5 M⊙ or less, in conflict with observations of neutron stars with masses up to ∼ 2 M⊙ .
Solving this puzzle with nuclear physics tools requires a detailed understanding of hyperon-nucleon (YN) interactions, hyperon-hyperon (YY) interactions, and three-body interactions involving hyper- ons and nucleons. In this talk, I will present the development of a local potential model for the \Lambda N interaction, derived using a low-energy EFT formalism that involves contact terms only. The present interaction has been derived up to next-to-leading order (NLO). I will also discuss the details of the fitting procedure to \Lambda p elastic scattering cross sections and present our results for different cutoff parameters up to 2.5 fm.Speaker: Margherita Sagina (University of Pisa, INFN) -
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The Experimental Study of Rare Kaon Decays at J-PARC with KOTO and KOTO II
The rare kaon decay $K_L \to \pi^0\nu\bar{\nu}$ is extremely sensitive to new physics, because in the Standard Model (SM) the decay is highly suppressed and its rate is known very accurately: its SM branching ratio (BR) is $3\times10^{-11}$ with a theoretical uncertainty of just 2\%. Measurement of this BR will provide essential new information about the flavor structure of the quark sector from the $s\to d$ transition. The decay is being searched for in the KOTO experiment at J-PARC, which has obtained the upper limit on the BR $2.2\times10^{-9}$; a sensitivity to branching ratios below $10^{-10}$ is achievable by the end of the decade. A next-generation experiment at J-PARC, KOTO II, was proposed in 2024 with 82 members worldwide, including significant contributions from European members, in particular from Italy. The goal of KOTO II is to measure ${\rm BR}(K_L \to \pi^0\nu\bar{\nu})$ with sensitivity below $10^{-12}$. Discovery of the decay with $5\sigma$ significance is achievable at the SM value of the BR. An indication of new physics with a significance of 90\% is possible if the observed branching ratio differs by 40\% from the SM value. Additional goals of KOTO II are to measure the BRs of the unobserved $K_L\to\pi^0 e^+e^-$ decay and of other rare $K_L$ decays, as well as to search for hidden-sector particles produced in $K_L$ decays. After 2026, KOTO will be the only dedicated rare kaon decay experiment in the world, and, as the only future rare kaon decay project currently proposed, KOTO II represents a global initiative for the future of the experimental study of rare kaon decays.
Speaker: Antonio Passeri (Istituto Nazionale di Fisica Nucleare)
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23
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11:00
Break
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Session 8Convener: Koji Miwa
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28
HOLMES - The Electron Capture Decay of Ho-163 to Measure the Electron Neutrino MassSpeaker: Matteo De Gerone (Istituto Nazionale di Fisica Nucleare)
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29
The Belle II experiment at the SuperKEKB collider
The Belle II experiment is an upgraded version of the previous Belle experiment and operates at the SuperKEKB energy asymmetric 𝑒+𝑒− collider located at the KEK laboratory in Tsukuba. Together the two experiments have collected more than 1.3 ab-1 of collision data at the Y(4S) resonance and about 200 fb-1 at other bottomonium resonances. A wide physics program has already started, including the measurement of the Cabibbo Kobayashi Maskawa matrix elements and their phases with unprecedented precision, the B and charmed mesons rare decays, 𝜏 lepton physics, lepton flavour violation searches, low-mass dark matter candidate searches, bottomonium spectroscopy and quantum entanglement tests. The Belle II experiment plans to collect few times more data during the current data taking campaign, and to reach up to 50 times more data thanks to a challenging upgrade program, both of the accelerator and of the detector, which is being currently developed.
Speaker: Antonio Passeri (Istituto Nazionale di Fisica Nucleare) -
30
A new low-energy antineutron beamline at the CERN Antiproton Decelerator
Antinucleon ($\bar{p}$ and $\bar{n}$) interactions with matter were extensively investigated at the CERN Low Energy Antiproton Ring (LEAR) for more than a decade throughout the 1980s and 1990s. Several series of systematic measurements of their cross sections on protons and nuclei led to significant advances in our understanding of hadronic interactions involving antimatter.
However, experimental data on low-energy $\bar{n}$ scattering remain scarce even today, thus limiting our knowledge of S-wave antinucleon-nucleon and antinucleon-nucleus interactions.
Recently, a collaboration of Japanese and European researchers has proposed a novel production scheme to provide very low-energy $\bar{n}$s and address this gap [1]. The leading idea is to exploit the backward-emitted $\bar{n}$s in the charge-exchange reaction ($\bar{p}$p → n$\bar{n}$ ), which can feature momenta down to a minimum value of 9 MeV/c, corresponding to a kinetic energy of only 43 keV. Such energies are well suited for the study of pure S-wave antinucleon-nucleon and antinucleon-nucleus interactions.
Preliminary tests indicate that such a low-energy $\bar{n}$ production scheme can be implemented at the CERN Antiproton Decelerator (AD) by using a modified extraction scheme, allowing the delivery of $\bar{p}$s at an intermediate momentum of 300 MeV/c.
[1] C. Amsler et. al, Letter of Intent, CERN-SPSC-2025-010 (2025) 1.Speaker: Alessandro Feliciello (Istituto Nazionale di Fisica Nucleare) - 31
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28
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13:30
Lunch
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Session 9Convener: Atsushi Tamii (Research Center for Nuclear Physics, the University of Osaka)
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32
Probing charge-exchange excitations with nuclear reactions
We review recent theoretical developments for the description of charge-exchange reactions involving heavy ions. In particular, second-order processes provide a crucial touchstone to test our understanding of the underlying physics mechanisms and the modelling of nuclear structure aspects. In this contribution, collisional heavy ion double charge exchange (DCE) reactions, induced by second order nucleon-nucleon interactions, are shown to provide access to the two-body transition densities (2BTD) of the complementary DCE transitions in the interacting nuclei, explicitly entering the reaction cross section. The theoretical results are applied to reaction systems investigated by the NUMEN collaboration. The 2BTD are evaluated adopting the HF+BCS+QRPA scheme, employing different Skyrme interactions, thus probing the sensitivity of the cross section to specific channels of the effective interaction. These investigations open the way for possible future comparisons between the predictions of different structure models and to probe their impact on charge-exchange reaction cross sections.
References:
1) J.I.Bellone, M.Colonna, D.Gambacurta and H.Lenske, Heavy-ion double-charge-exchange reactions as probes for two-body transition densities, Phys.Rev.C 111 (2025) 6, L061602
2) B.Urazbekov et al. (NUMEN Collaboration), Direct and two-step processes in the 275 MeV 40Ca(18O,18F)40K reaction within a unified model, Phys.Rev.C 111 (2025) 4, 044603Speaker: Maria Colonna (Istituto Nazionale di Fisica Nucleare) -
33
Halos, clusters, pairing: the Padova-Japan nucelar theory connection
I will discuss the contributions to nuclear theory (structure and reactions) that were born out of the collaboration between researchers working in Padova and in Japan in the last decade.
A few selected topics will be highlighted from various studies on pairing correlations, three-body models, nuclear halos, Borromean systems, nuclear molecule, cluster physics, transfer reactions, etc.Speaker: Lorenzo Fortunato (Istituto Nazionale di Fisica Nucleare) -
34
The LNS facility upgrade: status and perspectives
The INFN - Laboratori Nazionali del Sud in Catania has undergone a major renovation in the last five years. The upgrade of the superconducting cyclotron, the installation of a new fragment separator for the production of in-flight radioactive beams, not to mention the installation of a new laser facility or other experimental facility like Pandora. Also some of the largest apparata, like for example the spectrometer Magnex have undergone major upgrade. This presentation will highlight the new layout of the laboratory and the research perspectives and challenges that the laboratory offers.
Speaker: Alessia Francesca Di Pietro (Istituto Nazionale di Fisica Nucleare) - 35
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32
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16:15
Break
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Session 10Convener: Hidetoshi Yamaguchi (Center for Nuclear Study, the University of Tokyo)
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36
Study of break-up reaction of 8B
The reaction dynamics induced by light weakly-bound nuclei at energies around the Coulomb barrier has been a puzzle for many years. Compared to reactions induced by stable well-bound nuclei, these projectiles trigger a larger variety of nuclear processes while approaching a target nucleus. Being very weakly-bound, they can more easily breakup in the target Coulomb and nuclear field. At the same time, having usually a well-pronounced cluster structure, they could more likely transfer one of the fragments to the target. In turn, also the fusion process is strongly influenced by the unusually large cross sections for direct processes.
Within thin framework, we investigated in two experiments performed with the Radioactive Ion Beam facilities EXOTIC at INFN-LNL (Italy) and CRIB at RIKEN (Japan) the reaction dynamics induced by 7Be and 8B, respectively, on a 20Pb target at energies around the Coulomb barrier. In particular, we measured for the first time the elastic scattering process and the angular distributions for the production of projectile fragments. In the case of the 7Be+20Pb reaction, we observed also a few tens of He-He, He-3He and He-2H coincidences, clear fingerprints of a n-pickup, exclusive breakup and p-stripping mechanism, respectively. However, the largest majority (> 97%) of 3He and He ions were detected as singles events.
The recent upgrade of the facility EXOTIC, which has been coupled to the gamma-ray tracking spectrometer AGATA, should allow to perform particle-gamma coincidences between 7Be fragments and the Po isotopes produced after the 3He/He-stripping process and to shed some light on the reaction mechanisms underlying the 3He and He production. The work done for the upgrade of the facility, the connection to AGATA and the perspectives to perform particle-gamma correlation measurements for the system 7Be+20Pb will be eventually presented.Speaker: Marco Mazzocco (Istituto Nazionale di Fisica Nucleare) -
37
Projects related to Nuclear Astrophysics at RIBF and Future Perspectives
Approximately half of our solar system's elements are believed to have been synthesized through the rapid neutron-capture process (r-process), which occurs when a competition between neutron-capture reactions and β-decay takes place in extremely neutron-rich nuclei. Recent multi-messenger observations combining gravitational-wave and electromagnetic signals have provided compelling evidence for r-process nucleosynthesis, including the production of Sr, Y, Te, and lanthanide elements. Meanwhile, precise spectroscopy of metal-poor stars has enabled high-quality r-process elemental abundance data to constrain the physical conditions of the r-process.
In this presentation, we will report on experiments conducted at the Radioactive Isotope Beam Factory (RIBF) to investigate the mechanisms of r-process nucleosynthesis. Additionally, our perspective for future experimental programs will be discussed for potential collaboration opportunities.Speaker: Dr Shunji Nishimura (RIKEN Nishina Center (RNC)) -
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Beta-decays in stellar and laboratory plasmasSpeaker: Bharat Mishra (Istituto Nazionale di Fisica Nucleare)
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39
Investigation of linear chain states in 14C via the reaction 4He(10Be,6He) at LNS
Light nuclei may exhibit clustering behavior, with nucleon correlations giving rise to distinct groupings of protons and neutrons typically forming α particles. In some instances, these clusters assemble into molecular-like structures, bounded by valence nucleons that are shared between the clusters analogously to electrons in an atomic covalent bond. Linear-chain configurations of α particles bonded by neutrons through π or σ bonds are theoretically predicted to exist.
In this contribution we report preliminary results concerning the study of the possible σ-bond linear chain configurations of $^{14}$C, studied through the reaction $^4$He($^{10}$Be,$^6$He) measured at LNS.
The excitation function is reconstructed by the analysis of the $^6$He energy spectra in the excitation energy range 19-26 MeV, where the sought structures are expected to exist.Speaker: Martina Figuera (Università degli Studi di Catania) -
40
Nuclear clustering in nuclear matter and heavy-ion collisions from a kinetic approachSpeaker: Rui Wang (Istituto Nazionale di Fisica Nucleare)
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36
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Session 11Convener: Takashi Nakamura
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41
Quantum computing for the nuclear many-body problemSpeaker: Alessandro Roggero (Istituto Nazionale di Fisica Nucleare)
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42
Status of NUMEN experimentSpeaker: Manuela Cavallaro (INFN -LNS)
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Coupling of the EXOTIC facility to AGATA
I will present the results of the commissioning campaign coupling the EXOTIC facility with the AGATA γ‑ray tracking array, with a focus on the delivery of the radioactive ion beam inside the AGATA reaction chamber. I will also introduce the experiment planned with this configuration and share preliminary results from the first experimental campaigns.
Speaker: Anna Togni (Istituto Nazionale di Fisica Nucleare) -
44
First indirect measurement of the 26Al(n,p) and 26Al(n,α) cross sections in the context of Multimessenger Astronomy
The ADONIS experiment (Aluminum DestructION in Stars) is framed within the context of Multimessenger Astronomy and aims to improve the understanding of nucleosynthesis processes through the study of the radioactive isotope 26Al. This nucleus, the first γ-ray emitter observed in our Galaxy, is crucial for understanding the evolution of massive stars, the supernova explosions and the consequent formation of compact objects such as neutron stars. The experiment indirectly measures the cross sections of the neutron destruction channels 26Al(n,α) and 26Al(n,p), which are fundamental in determining the abundance of 26Al, by using the Trojan Horse Method (THM). This method overcomes the experimental difficulties related to cross-section measurements at astrophysically relevant energies by exploiting quasi-free breakup reaction mechanisms. The data, from the 2H+26Al experiment carried out using a radioactive 26Al beam at 3.5 MeV/u and silicon telescopes to detect the reaction products, make it possible to explore the astrophysically relevant energy range for 26Al synthesis in stellar environments (0–1 MeV).
The current status of the experiment’s data analysis will be presented, including the study of selected processes used as kinematic and dynamic checks for the correctness of the detectors’ energy and angular calibrations.Speaker: Francesco Andreis (UniPG, Istituto Nazionale di Fisica Nucleare) -
45
Superfluid Band Calculations for Neutron Star Inner Crust
Neutron stars are compact objects filled with nuclear (hadronic) matter that reaches several times the nuclear saturation density at their centers, and they are regarded as one of the frontier topics in modern theoretical physics. In the region known as the inner crust, a crystalline lattice of neutron-rich nuclei coexists with a superfluid gas of unbound neutrons, a state that carries crucial clues for interpreting a variety of astrophysical phenomena such as gamma-ray bursts and pulsar glitches.
A key issue in elucidating the inner-crust structure is how to incorporate the effects of crystallinity; to date, calculations based on the band theory have been pursued. Those studies have pointed to an “entrainment” effect in which band-structure physics increases the effective mass of free neutrons to several to ten times the bare mass, an assertion that remains the subject of vigorous debate.
In our work, we have developed a framework of “superfluid band-structure calculations” that extends band theory to include neutron superfluidity, and we are applying it to various types of crystal structures. For a simple one-dimensional crystal, our calculations indicate the occurrence of “anti-entrainment,” in which the neutron effective mass becomes smaller than the bare mass; we are now extending the approach to two- and three-dimensional structures.
In this presentation, I will report our results to date and outline future prospects.Speaker: Kenta Yoshimura (Institute of Science Tokyo) -
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Supersolidity as a probe for Compact Objects
Supersolidity is a peculiar phase of matter in which superfluidity and crystalline order coexist. Owing to this dual character, it provides a powerful platform for investigating systems with multiple simultaneously broken symmetries, such as nuclear matter in the interior of neutron stars. In this work, we simulate the dynamics of the neutron-star inner crust during a glitch, focusing on the excitations induced by density modulations and on interface effects arising between layers at different radial depths within the star.
Speaker: Silvia Trabucco (University of Innsbruck)
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41
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11:00
Break
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Session 12Convener: Silvio Cherubini (Istituto Nazionale di Fisica Nucleare)
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47
THM experiments with 7Be and related topics
Neutron induced reactions on unstable nuclei play a significant role in the nucleosynthesis of the elements in the cosmos. Their interest range from the primordial processes occurred during the Big Bang Nucleosynthesis up to the “stellar cauldrons” where neutron capture reactions build up heavy elements. In the last years, several efforts have been made to investigate the possibility of applying the Trojan Horse Method (THM) to neutron induced reactions mostly by using deuteron as “TH-nucleus”. Here, the main advantages of using THM will be given together with a more focused discussion on the 7Be-neutron induced reactions recently studied for BBN applications, being these the first THM cross section measurements for neutron induced reactions induced by radioactive nuclei. The experiment performed at INFN-LNL (Italy) and the one performed at CRIB-Univ. of Tokyo (Japan) will be discussed. These applications could open new frontiers in the application of the method (i.e. the study of 7Be+d or 11C+alpha reactions) extending its range of applicability for contributing to astrophysically relevant problems.
Speaker: Livio Lamia (Istituto Nazionale di Fisica Nucleare) -
48
Recent measurements with low-energy RI beams at CRIB
Radioactive isotope (RI) beams broaden our scope for
understanding the nature of exotic nuclei.
RI are rarely found on the earth, but can be artificially produced using
accelerated beams and special apparatuses.
One example is CRIB, an RI-beam separator of Center for Nuclear Study, the University of Tokyo,
installed in the RIBF of RIKEN Nishina Center.
It can produce low-energy (less than 10 MeV/u) RI beams
at a relatively high intensity by the in-flight method.Recent experimental projects include:
1) Simulations of X-ray bursters have indicated that the
RI-involving nuclear reaction rates could significantly affect the
profile of the observed X-ray light curve.
Experiments to evaluate the astrophysical reactions
in the region of proton-rich nuclei have been conducted at CRIB,
such as those for the 22Mg(alpha, p) and 26Si(alpha, p) reactions.2) The primordial lithium abundance in the Big-Bang nucleosynthesis (BBN)
still shows a discrepancy between the values by the stellar observation and by
the simulation based on the standard Big-Bang model.
To study the beryllium-7 destruction process, we studied 7Be+n reactions
using the Trojan-horse method. This project was in a deep collaboration between
Italy and Japan.3) Alpha-clustering is a special phenomenon often found in nuclear
excited states around the alpha-particle threshold.
There has been prediction of linear-chain cluster states, in which alpha particles
are linearly aligned in the nucleus, as an exotic form of alpha-clustering.
Search for the linear-chain states have been performed at CRIB, for the
nuclei of 14C and 14O.The latest experimental achievements of these subjects are introduced and discussed.
Speaker: Hidetoshi Yamaguchi (Center for Nuclear Study, the University of Tokyo) -
49
PANDORA Project: Photo-Nuclear Reaction of Light Nuclei
The study of photo-nuclear reactions is crucial for understanding nuclear structure and astrophysical processes. The PANDORA (Photo-Absorption of Nuclei and Decay Observation for Reactions in Astrophysics) project [1] aims to systematically investigate these reactions in stable nuclei with mass numbers below 60, both experimentally and theoretically. We use virtual photon exchange through proton scattering and high-intensity real-photon beams from laser Compton scattering to excite target nuclei. The subsequent decay particles and gamma-rays are detected to measure the photo-absorption cross-section and the decay branching ratio for each decay channel, covering the giant dipole resonance.
Several nuclear models, including anti-symmetrized molecular dynamics, mean-field type models, large-scale shell model, and ab initio models, will be employed to predict the systematic behavior of photo-nuclear reactions. The primary objective of the PANDORA project is to elucidate the energy loss mechanisms of ultra-high-energy cosmic ray (UHECR) nuclei during intergalactic propagation.
UHECRs, observed on Earth up to energies above 1020 eV by large cosmic-ray air-shower observatories such as Pierre Auger and Telescope Array, remain a mystery in terms of origin, acceleration mechanisms, and composition. Recent analyses suggest a heavier mass composition for UHECRs at the highest energies. UHECR nuclei are predicted to lose energy primarily by emitting particles following photo-nuclear excitation by cosmic microwave background photons. Thus, understanding photonuclear reaction cross-sections and decay branching ratios is essential for interpreting the energy and mass evolution of UHECRs.
I will introduce the experimental method [2] for studying the electric dipole excitation of nuclei and photo-nuclear reactions by proton scattering at the Research Center for Nuclear Physics, Osaka University, and report on the experiments conducted in 2023 and 2025.References
[1] A. Tamii et al., PANDORA White Paper, Euro. Phys. J. A. 59, 208 (2024).
[2] P. von Neumann-Cosel and A. Tamii, Euro. Phys. J. A 55, 110, (2019)Speaker: Atsushi Tamii (Research Center for Nuclear Physics, the University of Osaka) -
50
Probing nuclear interactions à la Rutherford: Insights on 4He from α scattering
The light nuclei attract the interest of the nuclear physics community for decades, however, we are still far away from their complete understanding. A notable example is the $^4$He, a simple and very stable nucleus constituted by two protons and two neutrons. Until a description of nuclei directly from the fundamental theory of quarks and gluons becomes computationally feasible, an effective way to proceed is to assume composite particles like protons and neutrons and the interactions among them as the basic degrees of freedom. Successful parameterizations and models of these interactions have been developed in the last decades, which are able to accurately reproduce all the known data of proton and neutron scatterings, as well as the properties of few-body nuclear systems. However, recent electron scattering results focusing on the first excited resonant state of $^4$He nucleus, reveal a puzzling situation suggesting potential gaps in our understanding of nuclear phenomenology. Into this context, we performed new measurements of the $^4$He(0$^+_2$) resonance by $^4$He + $^4$He scattering at the MAGNEX facility of INFN – Laboratori Nazionali del Sud, featuring data of unprecedented sensitivity and state-of-art analyses of the spectral line shape together with a phenomenological reaction modeling based on a two coupled-channel system that incorporates the same ab-initio nuclear densities employed in electron-scattering studies.
Speaker: Vasileios Soukeras (University of Catania and INFN-LNS) -
51
Closing remarks
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47
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13:30
Lunch
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