The progress of the study of unstable states in relativistic dissociation events of light nuclei in nuclear emulsion is presented. Identification of these states is possible by means of the invariant mass determined from the most accurate and complete measurements of relativistic fragment emission angles in the approximation of conservation of momentum per nucleon of the parent nucleus. It is established that excitations $^{12}\mathrm{C}(0^{+}_{2})$ and $^{12}\mathrm{C}(3^{-})$ lead in the dissociation $^{12}\mathrm{C} \rightarrow 3\alpha$ and $^{16}\mathrm{O} \rightarrow 4\alpha$. The contribution of $^{9}\mathrm{B}$ and $^{12}\mathrm{C}(0^{+}_{2})$ decays to the leading channel of $^{3}\mathrm{HeH}$ dissociation of the $^{14}\mathrm{N}$ nucleus is estimated. The motivation and the beginning of the analysis of the relativistic dissociation $^{16}\mathrm{O}$$\rightarrow$$^{12}\mathrm{C}\alpha$ are presented. The presented relativistic dissociation events at the $^{7}\mathrm{Be}$$\rightarrow$$^{6}\mathrm{Li}p$ and $^{11}\mathrm{C}$$\rightarrow$$ ^{7}\mathrm{Be}\alpha$ coupling threshold point to the prospect of moving beyond $\alpha$-particle clustering.

We show that recent measurements of substructure-dependent jet suppression constrain the value of the resolution length of the droplets of quark-gluon plasma (QGP) formed in heavy ion collisions. This resolution length, $L_{\rm res}$, is defined such that the medium can only resolve partons within a jet shower that are separated by more than $L_{\rm res}$. We first use Hybrid Model calculations to reproduce ALICE measurements of the scaled Soft Drop angle $\theta_g$ for anti-$k_t$ $R = 0.2$ jets reconstructed from charged-particle tracks. We find that the narrowing of the $\theta_g$-distribution in PbPb collisions compared to pp collisions that is seen in the ALICE data rules out a picture of fully coherent energy loss ($L_{\rm res} = \infty$) where each entire parton shower loses energy to the plasma as if it were a single unresolved colored object. We then use Hybrid Model calculations to reproduce ATLAS measurements of $dR_{12}$, the Soft Drop angle obtained by applying the Soft Drop grooming procedure to all charged-particle tracks in $R=1$ jets reconstructed from $R = 0.2$ skinny subjets. Our analysis demonstrates that the ATLAS measurements of $R_{\rm AA}$ for such $R = 1$ jets as a function of $dR_{12}$ are inconsistent with a picture of fully incoherent energy loss ($L_{\rm res} = 0$) in which every splitting in a parton shower is immediately resolved by the plasma. We find that our Hybrid Model calculations agree best with the ATLAS measurements if QGP has a finite, nonzero, resolution length $L_{\rm res}\sim (1-2)/(\pi T)$. For the first time, jet substructure measurements are constraining the resolution length of QGP from below, as well as from above.

The nature of octupole deformation, whether static or vibrational, remains an open question in nuclear physics. Here, we propose a scaling approach to probe this ambiguity by triangular flow fluctuations using multi-particle cumulants, $c_{3,\varepsilon}\{4\}$, in relativistic $^{238}$U+$^{238}$U collisions. We demonstrate that both $|c_{3,\varepsilon}\{4\}|$ and the ratio $|c_{3,\varepsilon}\{4\}/c^2_{3,\varepsilon}\{2\}|$ scale linearly with the fourth-order moment of octupole deformation, $\langle \beta^4_{3,\mathrm{U}} \rangle$. Combined with the known linear relation of $c_{3,\varepsilon}\{2\}$ to $\langle \beta^2_{3,\mathrm{U}} \rangle$, this new relation provides a direct extraction of both the mean and variance of the octupole deformation fluctuations, finally discriminating between static and dynamic origins. This work establishes a new tool to probe the static and dynamic collective modes in high-energy nuclear collisions, advancing a significant step toward refining the initial conditions of quark-gluon plasma.

In this contribution we review the algebraic cluster model (ACM) for $\alpha$-cluster nuclei with $A=4k$ nucleons and its extension to the cluster shell model (CSM) for $A=4k+x$ nuclei. Particular attention is paid to the question to what extent the $\alpha$-cluster structure survives under the addition of extra nucleons. As an example, we discuss the properties of $^{12}$C and $^{13}$C.

Low Gain Avalanche Diodes, also known as LGADs, are widely considered for fast-timing applications in high energy physics, nuclear physics, space science, medical imaging, and precision measurements of rare processes. Such devices are silicon-based and feature an intrinsic gain due to a $p{^+}$-doped layer that allows the production of a controlled avalanche of carriers, with multiplication on the order of 10-100. This technology can provide time resolution on the order of 20-30 ps, and variants of this technology can provide precision tracking too. The characterization of LGAD performance has so far primarily been focused on the interaction of minimum ionizing particles for high energy and nuclear physics applications. This article expands the study of LGAD performance to highly-ionizing particles, such as 28-MeV protons, which are relevant for several future scientific applications, e.g. in biology and medical physics, among others. These studies were performed with a beam of 28-MeV protons from a tandem Van de Graaff accelerator at Brookhaven National Laboratory and beta particles from a $^{90}{\rm Sr}$ source; these were used to characterize the response and the gain of an LGAD as a function of bias voltage and collected charge. The experimental results are also compared to TCAD simulations.

Azimuthal anisotropy scaling functions for identified mesons and baryons are analyzed in large (Pb+Pb at $\sqrt{s_{NN}} = 2.76$ and 5.02 TeV, Au+Au at $\sqrt{s_{NN}} = 200$ GeV), intermediate (Cu+Cu at $\sqrt{s_{NN}} = 200$~GeV), and small (p+Pb at $\sqrt{s_{NN}} = 5.02$ and 8.16 TeV, p+Au, d+Au, and $^3$He+Au at $\sqrt{s_{NN}} = 200$ GeV) collision systems. The scaling functions' fidelity supports a hydrodynamic-like origin for anisotropies in the flow-dominated regime. Central Pb+Pb, Au+Au, and Cu+Cu reflect QGP-driven expansion with strong radial flow and significant jet quenching, while peripheral Pb+Pb and Cu+Cu exhibit hadronic-dominated dynamics. In contrast, central RHIC small systems show hadronic-dominated behavior, with strong re-scattering, negligible radial flow, and suppressed jet quenching, following the hierarchy p+Au $>$ d+Au $>$ $^3$He+Au. At the LHC, ultra-central p+Pb collisions display enhanced radial flow, reduced re-scattering, and small but nonzero jet quenching. Scaling violations at high $p_T$ reflect partial suppression of partonic energy loss. These findings demonstrate that QGP-like behavior in small systems depends sensitively on both system size and beam energy, and establish the scaling framework as a robust diagnostic of collectivity and medium properties across diverse collision conditions.