arXiv subjects

Tian-Yu Wu

Publications and source records attributed to Tian-Yu Wu.

3 recordsLinked to original sources

arXiv2026

Best Reaction Target To Determine Proton Distribution Radii of Atomic Nuclei

We found that a heavy target such as Pb is most suitable for determining the proton distribution radii of unstable nuclei through charge-changing cross-section ($σ_\text{cc}$) measurements. As a heavy ion probe, low-$Z$ targets are routinely used to determine nucleon distribution radii of unstable isotopes. This approach has recently been extended to study proton distribution radii from $σ_\text{cc}$ measurements. However, empirical scaling factors have to be introduced to apply the Glauber models. In the present work, we systematically investigated the scaling factor using 39 new $σ_\text{cc}$ data of 18 $p$-shell nuclei on hydrogen, carbon, silver, and lead targets at around 240 MeV/nucleon. Together with the existing data, we reveal a universal dependence of the scaling factor on both the masses of target nuclei and the separation energies of projectile nuclei. The scaling factors decrease with increasing target-nucleus mass and converge to 1 for the highest-$Z$ target, making the scaling unnecessary. We conclude that instead of a low-$Z$ target, employing a heavy target such as Pb in $σ_\text{cc}$ measurements is the best option to determine the proton distribution radii of unstable nuclei.

nucl-ex↗

arXiv2026

Basis Representation for Nuclear Densities from Principal Component Analysis

We develop an efficient method to represent nuclear densities using basis functions extracted via Principal Component Analysis (PCA). Applying PCA to densities of 75 nuclei calculated with the relativistic continuum Hartree-Bogoliubov (RCHB) theory yields an orthogonal set of components that efficiently capture the dominant features of nuclear density distributions, which can be used as basis functions for nuclear density representation. The first five basis functions account for more than 99.999\% of the total variance, demonstrating the efficiency of these PCA basis functions. The PCA basis achieves significantly higher accuracy and faster convergence than the Fourier-Bessel and Sum-of-Gaussians methods for reconstructing both theoretical and experimental densities. This approach provides an efficient and robust representation of nuclear densities, offering a practical tool for experimental density representation and for theories where densities play a central role, such as the orbital-free density functional theory, or the double folding model for nuclear reactions.

nucl-th↗

arXiv2025

Full realization of the RIBLL2 separator at the HIRFL-CSR facility

A new experimental platform was constructed at the Second Radioactive Ion Beam Line in Lanzhou (RIBLL2) of HIRFL-CSR accelerator facility at Lanzhou, China. Its performance, along with several newly developed detectors, was tested in two radioactive ion beam experiments utilizing a 400 MeV/u 40Ar beam and a 350 MeV/u 78Kr beam, respectively. The first results from these two experiments demonstrate a good particle identification capability of the setup, thereby affirming the full realization of the RIBLL2 separator.

physics.ins-det↗