Tue·Oct 24, 2023Tuesday·October 24, 2023

1. 01*

   Isospin-dependence of the charge-changing cross-section shaped by the charged-particle evaporation process

   J.W. Zhao🇩🇪 · B.-H. Sun · I. Tanihata🇯🇵 · S. Terashima🇨🇳 · A. Prochazka🇩🇪 · J.Y. Xu🇨🇳 · L.H. Zhu🇨🇳 · J. Meng🇨🇳 · J. Su · K.Y. Zhang🇨🇳 · L.S. Geng🇨🇳 · L.C. He and 17 other authors

   We present the charge-changing cross sections (CCCS) of ${}^{11-15}$C, ${}^{13-17}$N, and ${}^{15,17-18}$O at around 300 MeV/nucleon on a carbon target, which extends to $p$-shell isotopes with $N<Z$ for the first time. The Glauber model, which considers only the proton distribution of projectile nuclei, underestimates the cross sections by more than 10\%. We show that this discrepancy can be resolved by considering the contribution from the charged-particle evaporation process (CPEP) following projectile neutron removal. Using nucleon densities from the deformed relativistic Hartree-Bogoliubov theory in continuum, we investigate the isospin-dependent CPEP contribution to the CCCS for a wide range of neutron-to-proton separation energy asymmetry. Our calculations, which include the CPEP contribution, agree well with existing systematic data and reveal an ``evaporation peak" at the isospin symmetric region where the neutron-to-proton separation energy is close to zero. These results suggest that analysis beyond the Glauber model is crucial for accurately determining nuclear charge radii from CCCSs.

   nucl-exnucl-thPLB(2023)·25 citations
2. 02*

   Modeling alpha particle-induced radioluminescence using GEANT4

   Claudia Olaru · Mihail-Razvan Ioan · Mastaneh Zadehrafi

   Optical detection of alpha particle emitters in the environment by air radioluminescence is a new technology that enables sensing a radiological threat at safe distances, without putting personnel at risk or contaminating equipment. Radioluminescence detection systems need to be fine-tuned to efficiently capture a substantial number of photons while minimizing the contribution from ambient ultraviolet light. The accurate simulation of radioluminescence, in conjunction with ray tracing, facilitates the design and optimization of such detection systems. In this work, an application within the Geant4 framework has been developed to simulate radioluminescence photons emitted in the vicinity of accelerated alpha particles and at the surface of alpha radioactive samples. The application relies on existing scintillation physics implemented in Geant4 classes such as G4OpticalPhysics and G4Scintillation, which are used to simulate radioluminescence photons as scintillations produced during the passage of alpha particles through air. The application computes the ultraviolet image of alpha particles accelerated at energies of 5.1 MeV and 8.3 MeV, as well as an extended alpha source. The application enables optimization of experimental setups for various scenarios, such as radiological emergency management, radiological crime scene investigations, or decommissioning of nuclear facilities, thus minimizing the use of costly resources and exposure to radiation.

   nucl-exphysics.ins-detRom.J.Phys.(2023)·0 citations
3. 03*

   One-neutron transfer reaction in the ${}^{18}$O + ${}^{48}$Ti collision at 275 MeV

   O. Sgouros🇮🇹 · M. Cutuli🇮🇹 · F. Cappuzzello🇮🇹 · M. Cavallaro🇮🇹 · D. Carbone🇮🇹 · C. Agodi🇮🇹 · G. De Gregorio🇮🇹 · A. Gargano🇮🇹 · R. Linares🇧🇷 · G. A. Brischetto🇮🇹 · D. Calvo🇮🇹 · E. R. Chavez Lomeli🇲🇽 and 20 other authors

   The present article reports new data on the ${}^{48}$Ti(${}^{18}$O,${}^{17}$O)${}^{49}$Ti reaction at 275 MeV incident energy as part of the systematic research pursued within the NUMEN project. Supplementary measurements of the same reaction on ${}^{16}$O and ${}^{27}$Al targets were also performed in order to estimate the background arising from the use of a composite target (TiO${}_2$ + ${}^{27}$Al). These data were analyzed under the same theoretical framework as those obtained with the titanium target in order to reinforce the conclusions of our analysis. Differential cross-section angular distribution measurements for the ${}^{17}$O${}^{8+}$ ejectiles were performed in a wide angular range by using the MAGNEX large acceptance magnetic spectrometer. The experimental results were analyzed within the distorted-wave and coupled-channels Born Approximation frameworks. The optical potentials at the entrance and exit channels were calculated in a double folding approach adopting the São Paulo potential, and the spectroscopic amplitudes for the projectile and target overlaps were obtained from large-scale shell model calculations. The differential cross-sections are well-described by the theoretical calculations, where a weak coupling to collective excitations of projectile and target is inferred. The sensitivity of transfer cross-sections on different model spaces adopted in nuclear structure calculations, is also discussed.

   nucl-exnucl-thPRC(2023)·15 citations
4. 04*

   Electromagnetic Properties of Indium Isotopes Elucidate the Doubly Magic Character of ${}^{100}$Sn

   J. Karthein🇺🇸 · C.M. Ricketts🇬🇧 · R.F. Garcia Ruiz🇺🇸 · J. Billowes🇬🇧 · C.L. Binnersley🇬🇧 · T.E. Cocolios🇧🇪 · J. Dobaczewski🇬🇧 · G.J. Farooq-Smith🇧🇪 · K.T. Flanagan🇬🇧 · G. Georgiev🇫🇷 · W. Gins🇧🇪 · R.P. de Groote🇧🇪 and 15 other authors

   Our understanding of nuclear properties in the vicinity of ${}^{100}$Sn, suggested to be the heaviest doubly magic nucleus with equal numbers of protons (Z=50) and neutrons (N=50), has been a long-standing challenge for experimental and theoretical nuclear physics. Contradictory experimental evidence exists on the role of nuclear collectivity in this region of the nuclear chart. Using precision laser spectroscopy, we measured the ground-state electromagnetic moments of indium (Z=49) isotopes approaching the N=50 neutron number down to 101In, and nuclear charge radii of 101-131In spanning almost the complete range between the two major neutron closed-shells at N=50 and N=82. Our results for both nuclear charge radii and quadrupole moments reveal striking parabolic trends as a function of the neutron number, with a clear reduction toward these two neutron closed-shells, thus supporting a doubly magic character of ${}^{100}$Sn. Two complementary nuclear many-body frameworks, density functional theory and ab initio methods, elucidate our findings. A detailed comparison with our experimental results exposes deficiencies of nuclear models, establishing a benchmark for future theoretical developments.

   nucl-exnucl-thphysics.atom-phNat.Phys.(2024)·40 citations
5. 05*

   The optical potentials and nuclear reaction cross sections for the $n$-${}^{12}$C and $N$-${}^{12}$C scattering

   Imane Moumene🇮🇹 · Angela Bonaccorso🇮🇹

   In this work we extend a previously derived $n$- ${}^9$Be optical potential up to 500 MeV and apply it to the system $n$- ${}^{12}$C, finding excellent results for the energy dependence of the total cross sections. Results obtained with a standard optical model calculation are compared to those from the eikonal formalism in order to asses the accuracy of the latter as a function of the nucleon incident energy. For comparison, single folded (s.f.) nucleon-target potentials are also obtained using ${}^{12}$C densities from different models. These potentials are sensitive to the density used and none of them reproduce the characteristics of the phenomenological potential nor the cross section results. We then calculate nucleus-nucleus ($NN$) potentials and total reaction cross sections for some "normal" and exotic projectile nuclei on ${}^{12}$C within the eikonal formalism. We find that single folded (S.F.) projectile-target imaginary potentials and double folded (D.F.) potentials can produce similar energy dependence of the reaction cross sections but the S.F. results agree better with experimental data provided the radius parameter of the phenomenological $n$-target potential is allowed to be energy dependent. We conclude that the results previously obtained for a ${}^9$Be target are quite general, at least for light systems, and that a S.F. $NN$ potential built on a phenomenological nN potential can constitute an interesting and useful alternative to D.F. potentials.

   ↳ nucl-thnucl-exPRC(2023)·2 citations
6. 06*

   Spin asymmetry and dipole moments in $\tau$-pair production with ultraperipheral heavy ion collisions

   Ding Yu Shao🇨🇳 · Bin Yan🇨🇳 · Shu-Run Yuan🇨🇳 · Cheng Zhang🇨🇳

   The anomalous magnetic (MDM) and electric (EDM) dipole moments of the $\tau$ lepton serve as crucial indicators of new physics beyond the Standard Model. Leveraging azimuthal angular asymmetry as a novel tool in ultraperipheral collisions (UPCs), we attain unparalleled precision in the study of these key properties. Driven by the highly linear polarization of coherent photons, this method uniquely enables both the MDM and EDM to contribute to the $\cos 2\varphi$ angular distribution in similar magnitudes. Importantly, our approach substantially narrows the parameter space, excluding more than half of it compared to expected UPC-based measurements reliant solely on the total cross-section. This method not only provides improved constraints but also minimizes the need for additional theoretical assumptions.

   ↳ hep-phhep-exnucl-exnucl-thSCPMA(2024)·45 citations
7. 07*

   Fast 2D Bicephalous Convolutional Autoencoder for Compressing 3D Time Projection Chamber Data

   Yi Huang🇺🇸 · Yihui Ren🇺🇸 · Shinjae Yoo🇺🇸 · Jin Huang🇺🇸

   High-energy large-scale particle colliders produce data at high speed in the order of 1 terabytes per second in nuclear physics and petabytes per second in high-energy physics. Developing real-time data compression algorithms to reduce such data at high throughput to fit permanent storage has drawn increasing attention. Specifically, at the newly constructed sPHENIX experiment at the Relativistic Heavy Ion Collider (RHIC), a time projection chamber is used as the main tracking detector, which records particle trajectories in a volume of a three-dimensional (3D) cylinder. The resulting data are usually very sparse with occupancy around 10.8%. Such sparsity presents a challenge to conventional learning-free lossy compression algorithms, such as SZ, ZFP, and MGARD. The 3D convolutional neural network (CNN)-based approach, Bicephalous Convolutional Autoencoder (BCAE), outperforms traditional methods both in compression rate and reconstruction accuracy. BCAE can also utilize the computation power of graphical processing units suitable for deployment in a modern heterogeneous high-performance computing environment. This work introduces two BCAE variants: BCAE++ and BCAE-2D. BCAE++ achieves a 15% better compression ratio and a 77% better reconstruction accuracy measured in mean absolute error compared with BCAE. BCAE-2D treats the radial direction as the channel dimension of an image, resulting in a 3x speedup in compression throughput. In addition, we demonstrate an unbalanced autoencoder with a larger decoder can improve reconstruction accuracy without significantly sacrificing throughput. Lastly, we observe both the BCAE++ and BCAE-2D can benefit more from using half-precision mode in throughput (76-79% increase) without loss in reconstruction accuracy. The source code and links to data and pretrained models can be found at https://github.com/BNL-DAQ-LDRD/NeuralCompression_v2.

   ↳ stat.MLcs.LGhep-exnucl-ex4 citations
8. 08*

   CdZnTe detectors tested at the DA{\Phi}NE collider for future kaonic atoms measurements

   A. Scordo · L. Abbene · F. Artibani · M. Bazzi · M. Bettelli · D. Bosnar · G. Borghi · M. Bragadireanu · A. Buttacavoli · M. Cargnelli · M. Carminati · A. Clozza and 33 other authors

   The SIDDHARTA-2 collaboration at the INFN Laboratories of Frascati (LNF) aims to perform groundbreaking measurements on kaonic atoms. In parallel and beyond the ongoing kaonic deuterium, presently running on the DA$\Phi$NE collider at LNF, we plan to install additional detectors to perform further kaonic atoms' studies, taking advantage of the unique low energy and low momentum spread $K^{-}$ beam delivered by the at-rest decay of the $\varphi$ meson. CdZnTe devices are ideal for detecting transitions toward both the upper and lower levels of intermediate-mass kaonic atoms, like kaonic carbon and aluminium, which have an important impact on the strangeness sector of nuclear physics. We present the results obtained in a set of preliminary tests conducted on DA$\Phi$NE, in view of measurements foreseen in 2024, with the twofold aim to tune the timing window required to reject the extremely high electromagnetic background, and to quantify the readout electronics saturation effect due to the high rate, when placed close to the Interaction Region (IR). In the first test we used commercial devices and electronics, while for the second one both were customized at the IMEM-CNR of Parma and the University of Palermo. The results confirmed the possibility of finding and matching a proper timing window where to identify the signal events and proved better performances, in terms of energy resolution, of the custom system. In both cases, strong saturation effects were confirmed, accounting for a loss of almost 90\% of the events, which will be overcome by a dedicated shielding structure foreseen for the final experimental setup.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2024)·13 citations
9. 09*

   Probing Transverse Momentum Dependent Structures with Azimuthal Dependence of Energy Correlators

   Zhong-Bo Kang🇺🇸 · Kyle Lee🇺🇸 · Ding Yu Shao🇨🇳 · Fanyi Zhao🇺🇸

   We study the azimuthal angle dependence of the energy-energy correlators $⟨\mathcal{E}({\hat{n}}_1)\mathcal{E}({\hat{n}}_2)⟩$ in the back-to-back region for $e^{+}{e}^{-}$ annihilation and deep inelastic scattering (DIS) processes with general polarization of the proton beam. We demonstrate that the polarization information of the beam and the underlying partons from the hard scattering is propagated into the azimuthal angle dependence of the energy-energy correlators. In the process, we define the Collins-type EEC jet functions and introduce a new EEC observable using the lab-frame angles in the DIS process. Furthermore, we extend our formalism to explore the two-point energy correlation between hadrons with different quantum numbers ${\mathbb{S}}_i$ in the back-to-back limit $⟨{\mathcal{E}}_{{\mathbb{S}}_1}({\hat{n}}_1){\mathcal{E}}_{{\mathbb{S}}_2}({\hat{n}}_2)⟩$. We find that in the Operator Product Expansion (OPE) region the nonperturbative information is entirely encapsulated by a single number. Using our formalism, we present several phenomenological studies that showcase how energy correlators can be used to probe transverse momentum dependent structures.

   ↳ hep-phhep-exnucl-exnucl-thJHEP(2024)·51 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.