Thu·Sep 26, 2024Thursday·September 26, 2024

1. 01*

   Quasielastic $\overrightarrow{{}^3\mathrm{He}}(\overrightarrow{e},e^{\prime })$ Asymmetry in the Threshold Region

   M. Nycz · W. Armstrong · T. Averett · C.Ayerbe Gayoso · X. Bai · J. Bane · S. Barcus · J. Benesch · H. Bhatt · D. Bhetuwal · D. Biswas · A. Camsonne and 88 other authors

   A measurement of the double-spin asymmetry from electron-${}^3$He scattering in the threshold region of two- and three-body breakup of ${}^3$He was performed at Jefferson Lab, for Q${}^2$ values of 0.1 and 0.2 (GeV/$c$)${}^2$. The results of this measurement serve as a stringent test of our understanding of few-body systems. When compared with calculations from plane wave impulse approximation and Faddeev theory, we found that the Faddeev calculations, which use modern nuclear potentials and prescriptions for meson-exchange currents, demonstrate an overall good agreement with data.

   nucl-exPLB(2026)·0 citations
2. 02*

   First Use of a Polarized ${}^3$He Neutron Spin Filter on the Back-n White Neutron Source of CSNS

   Mofan Zhang · Zhou Yang · Junpei Zhang · Chuyi Huang · Tianhao Wang · Yonghao Chen · Ruirui Fan · W. Michael Snow

   Polarized eV neutrons can address interesting scientific questions in nuclear physics, particle physics, and astrophysics/cosmology. We present the first experiment to polarize the neutrons on the Back-n beamline at the Chinese Spallation Neutron Source (CSNS) using an in-situ NSF using spin-exchange optical pumping (SEOP) of 3He. A 3He polarization of 68%$\pm$0.7% for this in-situ NSF was measured through neutron transmission method at Back-n.This is high enough to enable new experiments on the Back-n beamline. Polarized neutron, Polarized nuclei, CSNS, White neutron, Fundamental physics research PACS number(s): 24.80.+y, 67.30.ep, 29.27.Hj , 24.70.+s , 32.10.Dk

   nucl-exNucl.Instrum.Meth.A(2025)·1 citation
3. 03*

   Numerical Modelling of Active Target Time Projection Chamber for Low Energy Nuclear Physic

   Pralay Kumar Das🇮🇳 · Jaydeep Datta🇺🇸 · Nayana Majumdar · Supratik Mukhopadhyay🇮🇳

   A numerical model based on hydrodynamic approach has been developed to emulate the device dynamics of active target Time Projection Chamber which is utilized for studying nuclear reaction through three dimensional tracking of concerned low energy particles. The proposed model has been used to investigate the performance of a prototype active target Time Projection Chamber, namely SAT-TPC, to be fabricated at Saha Institute of Nuclear Physics, for its application in nuclear physics experiments. A case study of non-relativistic elastic scattering ${}^{4}He{+}^{12}C$ with beam energy $25MeV$ and current $2.3pA$ has been opted for this purpose. The effect of beam induced space charge on the tracking performance the SAT-TPC prototype has been studied to optimize the beam current and scheme of the anode readout segmentation. The model has been validated by comparing its results to that of a particle model used to explain observed distortion in scattered particle tracks in a low energy nuclear physics experiment.

   ↳ physics.ins-detnucl-exJINST(2025)·2 citations
4. 04*

   Constraints on the Equation of State of Nuclear Matter from Systematically Comparing SMASH Calculations to HADES Data

   Justin Mohs🇩🇪 · Simon Spies🇩🇪 · Hannah Elfner🇩🇪

   We aim to constrain the equation of state of nuclear matter by comparing calculations with the SMASH transport model to directed and elliptic flow measurements for protons and deuterons performed by the HADES collaboration in a systematic way. A momentum-dependent term is included in the potential for which we show that it is needed to describe flow data. We further incorporate a simple symmetry potential in the transport model and present constraints on the stiffness of the equation of state of nuclear matter at saturation density and on the symmetry potential. The constraints are obtained by performing a Bayesian analysis such that we can also provide an uncertainty for the estimated parameters. The posterior distribution is obtained by Markov chain Monte Carlo sampling for which we emulate the transport model with a Gaussian process to lower computational costs. We find that a relatively stiff equation of state is favoured in our analysis with a small uncertainty whereas the constraints obtained for the symmetry potential are rather loose.

   ↳ nucl-thnucl-exPRC(2025)·18 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.