Fri·Dec 22, 2023Friday·December 22, 2023

1. 01*

   Impact of the MARATHON data on $F_{2n}/F_{2p}$ and off-shell effects in light nuclei

   T. J. Hague (1) · J. Arrington (1) · S. Li (1) · S. N. Santiesteban (2) ((1) Lawrence Berkeley National Laboratory · (2) University of New Hampshire)

   The neutron structure function, $F_{2n}$, has historically been extracted from measurements of the deuteron structure function, but our understanding of the nuclear effects on the bound proton and neutron limits the extraction of $F_{2n}$. The MARATHON collaboration recently extracted $F_{2n}$ from the comparison of ${}^3$H and ${}^3$He targets, where the nuclear effects are larger but nearly identical, yielding a precise extraction of $F_{2n}/F_{2p}$. This precise extraction can then be compared to deuteron extractions, providing important constraints on the nuclear effects in the deuteron. To ensure that this comparison is not biased by the specific model of nuclear effects used by MARATHON, we examine a range of models of the nuclear effects to obtain a more conservative, but more model-independent, extraction of $F_{2n}/F_{2p}$ for comparison with deuteron extractions. Even with the more conservative approach, the comparison suggests the need for significant off-shell corrections or other nuclear effects, beyond those include in most calculations, even for the weakly-bound deuteron.

   nucl-exnucl-thPRC(2024)·2 citations
2. 02*

   First measurement of the neutron-emission probability with a surrogate reaction in inverse kinematics at a heavy-ion storage ring

   M. Sguazzin🇫🇷 · B. Jurado🇫🇷 · J. Pibernat🇫🇷 · J. A. Swartz🇫🇷 · M. Grieser🇩🇪 · J. Glorius🇩🇪 · Yu. A. Litvinov · J. Adamczewski-Musch🇩🇪 · P. Alfaurt🇫🇷 · P. Ascher🇫🇷 · L. Audouin🇫🇷 · C. Berthelot🇫🇷 and 41 other authors

   Neutron-induced reaction cross sections of short-lived nuclei are imperative to understand the origin of heavy elements in stellar nucleosynthesis and for societal applications, but their measurement is extremely complicated due to the radioactivity of the targets involved. One way of overcoming this issue is to combine surrogate reactions with the unique possibilities offered by heavy-ion storage rings. In this work, we describe the first surrogate-reaction experiment in inverse kinematics, which we successfully conducted at the Experimental Storage Ring (ESR) of the GSI/FAIR facility, using the 208Pb(p,p') reaction as a surrogate for neutron capture on 207Pb. Thanks to the outstanding detection efficiencies possible at the ESR, we were able to measure for the first time the neutron-emission probability as a function of the excitation energy of 208Pb. We have used this probability to select different descriptions of the gamma-ray strength function and nuclear level density, and provide reliable results for the neutron-induced radiative capture cross section of 207Pb at energies for which no experimental data exist.

   nucl-exPRL(2025)·11 citations
3. 03*

   Beam Tests of SNSPDs with 120 GeV Protons

   Sangbaek Lee🇺🇸 · Tomas Polakovic🇺🇸 · Whitney Armstrong🇺🇸 · Alan Dibos🇺🇸 · Timothy Draher🇺🇸 · Nathaniel Pastika🇺🇸 · Zein-Eddine Meziani🇺🇸 · Valentine Novosad🇺🇸

   We report the test results for a 120 GeV proton beam incident on superconducting nanowire particle detectors of various wire sizes. NbN devices with the same sensitive area were fabricated with different wire widths and tested at a temperature of 2.8 K. The relative detection efficiency was extracted from bias current scans for each device. The results show that the wire width is a critical factor in determining the detection efficiency and larger wire widths than 400 nm leads to inefficiencies at low bias currents. These results are particularly relevant for novel applications at accelerator facilities, such as the Electron-Ion Collider, where cryogenic cooling is readily available.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2024)·4 citations
4. 04*

   Impact of tensor interactions and scalar mixing on covariant energy density functionals

   Marc Salinas🇺🇸 · Jorge Piekarewicz🇺🇸

   The recent pioneering campaigns conducted by the Lead Radius Experiment (PREX) and the Calcium Radius Experiment (CREX) collaborations have uncovered major deficiencies in the theoretical description of some fundamental properties of atomic nuclei. Following a recent refinement to the isovector sector of covariant energy density functionals [1], we present here additional improvements to the functional by including both tensor couplings and an isoscalar-isovector mixing term in the scalar sector. Motivated by the distinct surface properties of calcium and lead, we expect that the tensor terms that generate derivative couplings will help break the linear correlation between the neutron skin thickness of these two nuclei. Moreover, the addition of these new terms mitigates most of the problems identified in Ref.[1] in describing the properties of both finite nuclei and neutron stars. While significant progress has been made in reconciling the PREX-CREX results without compromising other observables, the final resolution awaits the completion of a proper calibration for this new class of functionals. We expect that powerful reduced basis methods used recently to create efficient emulators will be essential to accomplish this task.

   ↳ nucl-thnucl-exPRC(2024)·18 citations
5. 05*

   Probing configuration of $\alpha$ clusters with spectator particles in relativistic heavy-ion collisions

   Lu-Meng Liu🇨🇳 · Song-Jie Li🇨🇳 · Zhen Wang🇨🇳 · Jun Xu🇨🇳 · Zhong-Zhou Ren🇨🇳 · Xu-Guang Huang🇨🇳

   We propose to use spectator particle yield ratios to probe the configuration of $\alpha$ clusters in ${}^{12}$C and ${}^{16}$O by their collisions at RHIC and LHC energies. The idea is illustrated based on initial density distributions with various $\alpha$-cluster configurations generated by a microscopic cluster model, and without $\alpha$ clusters from mean-field calculations. The multifragmentation of the spectator matter produces more spectator light nuclei including $\alpha$ clusters in collisions of nuclei with chain structure of $\alpha$ clusters, compared to those of nuclei with a more compact structure. The yield ratio of free spectator neutrons to spectator particles with mass-to-charge ratio $A/Z=2$ scaled by their masses can be practically measured by the zero-degree calorimeter (ZDC) at RHIC and LHC, serving as a clean probe free from modeling the complicated dynamics at midrapidities.

   ↳ nucl-thhep-exnucl-exPLB(2024)·16 citations
6. 06*

   Measurements of higher-order cumulants of multiplicity and net-electric charge distributions in inelastic proton-proton interactions by NA61/SHINE

   NA61/SHINE: H. Adhikary🇵🇱 · P. Adrich🇵🇱 · K.K. Allison🇺🇸 · N. Amin🇩🇪 · E.V. Andronov · I.-C. Arsene🇳🇴 · M. Bajda🇵🇱 · Y. Balkova🇵🇱 · D. Battaglia🇺🇸 · A. Bazgir🇵🇱 · S. Bhosale🇵🇱 · M. Bielewicz🇵🇱 and 137 other authors

   This paper presents the energy dependence of multiplicity and net-electric charge fluctuations in p+p interactions at beam momenta 20, 31, 40, 80, and 158 GeV/c. Results are corrected for the experimental biases and quantified with the use of cumulants and factorial cumulants. Cumulant ratios are an essential tool in the search for the critical point of strongly interacting matter in heavy ion collisions. Measurements performed in p+p interactions provide a vital baseline estimation in these studies. The measured signals are compared with the string hadronic models EPOS1.99 and FTFP-BERT.

   ↳ hep-exnucl-exEPJC(2024)·6 citations
7. 07*

   Optical Transmission Enhancement of Ionic Crystals via Superionic Fluoride Transfer: Growing VUV-Transparent Radioactive Crystals

   Kjeld Beeks🇨🇭 · Tomas Sikorsky · Fabian Schaden🇦🇹 · Martin Pressler · Felix Schneider🇦🇹 · Björn N. Koch · Thomas Pronebner · David Werban · Niyusha Hosseini🇦🇹 · Georgy Kazakov · Jan Welch · Johannes H. Sterba · Florian Kraus · Thorsten Schumm🇦🇹

   The 8 eV first nuclear excited state in ${}^{229}$Th is a candidate for implementing an nuclear clock. Doping ${}^{229}$Th into ionic crystals such as CaF${}_2$ is expected to suppress non-radiative decay, enabling nuclear spectroscopy and the realization of a solid-state optical clock. Yet, the inherent radioactivity of ${}^{229}$Th prohibits the growth of high-quality single crystals with high ${}^{229}$Th concentration; radiolysis causes fluoride loss, increasing absorption at 8 eV. We overcome this roadblock by annealing ${}^{229}$Th doped CaF${}_2$ at 1250$℃$ in CF${}_4$. The technique presented here allows to adjust the fluoride content without crystal melting, preserving its single-crystal structure. Superionic state annealing ensures rapid fluoride distribution, creating fully transparent and radiation-hard crystals. This approach enables control over the charge state of dopants which can be used in deep UV optics, laser crystals, scintillators, and nuclear clocks.

   ↳ cond-mat.mtrl-scinucl-exPRB(2024)·16 citations
8. 08*

   Nucleon to $\Delta$ axial and pseudoscalar transition form factors

   Chen Chen🇨🇳 · Christian S. Fischer🇩🇪 · Craig D. Roberts🇨🇳

   A symmetry-preserving continuum approach to the calculation of baryon properties in relativistic quantum field theory is used to predict all form factors associated with nucleon-to-$\Delta$ axial and pseudoscalar transition currents, thereby unifying them with many additional properties of these and other baryons. The new parameter-free predictions can serve as credible benchmarks for use in analysing existing and anticipated data from worldwide efforts focused on elucidation of $\nu$ properties.

   ↳ hep-phhep-exhep-latnucl-ex+1PRL(2024)·20 citations
9. 09*

   Deuteron production in a combined thermal and coalescence framework for heavy-ion collisions in the few-GeV energy regime

   Wojciech Florkowski🇵🇱 · Radoslaw Ryblewski🇵🇱 · Piotr Salabura🇵🇱 · Nikodem Witkowski🇵🇱

   A recently formulated thermal model for hadron production in heavy-ion collisions in the few-GeV energy regime is combined with the idea that some part of protons and neutrons present in the original thermal system forms deuterons via the coalescence mechanism. Using realistic parametrizations of the freeze-out conditions, which reproduce well the spectra of protons and pions, we make predictions for deuteron transverse-momentum and rapidity spectra. The best agreement with the experimentally known deuteron yield is obtained if the freeze-out temperature is relatively high and, accordingly, the system size at freeze-out is rather small. In addition, the standard Gaussian distribution of the relative distance between nucleons is replaced by the distribution resulting from their independent and approximately uniform production inside the initial thermal system.

   ↳ nucl-thhep-phnucl-exActa Phys.Polon.B(2024)·5 citations
10. 10*

    Global Characterization of a Laser-Generated Neutron Source

    D. P. Higginson🇫🇷 · R. Lelièvre🇫🇷 · L. Vassura🇫🇷 · M. M. Gugiu🇷🇴 · M. Borghesi🇮🇹 · L. A. Bernstein🇺🇸 · D. L. Bleuel🇺🇸 · B. L. Goldblum🇺🇸 · A. Green🇬🇧 · F. Hannachi🇫🇷 · S. Kar🇬🇧 · S. Kisyov🇺🇸 and 8 other authors

    Laser-driven neutron sources are routinely produced by the interaction of laser-accelerated protons with a converter. They present complementary characteristics to those of conventional accelerator-based neutron sources (e.g. short pulse durations, enabling novel applications like radiography). We present here results from an experiment aimed at performing a global characterization of the neutrons produced using the Titan laser at the Jupiter Laser Facility (Livermore, USA), where protons were accelerated from 23 $\mu m$ thick plastic targets and directed onto a LiF converter to produce neutrons. For this purpose, several diagnostics were used to measure these neutron emissions, such as CR-39, activation foils, Time-of-Flight detectors and direct measurement of ${}^7$Be residual activity in the LiF converters. The use of these different, independently operating diagnostics enables comparison of the various measurements performed to provide a robust characterization. These measurements led to a neutron yield of $2.10^9$ neutrons per shot with a modest angular dependence, close to that simulated.

    ↳ physics.acc-phnucl-exphysics.plasm-phJ.Plasma Phys.(2024)·3 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.