The annihilation and radiative decay widths of fully charmed hadrons are investigated using a non-relativistic phenomenological potential model. The wavefunctions and model parameters obtained by solving the non-relativistic Schrodinger equation are used to calculate the various decay widths. The annihilation decay widths of charmonium, radiative decay widths of charmonium and triply charmed baryons are evaluated. It is seen that the radiative decays of charmonium are dominated by E1 and M1 transitions, whereas for triply charmed baryons the radiative decays are dominated by E2 and M1 transitions.
The determination of the critical temperature T_c in strongly interacting matter is central to understanding the transition between confined hadronic matter and deconfined quark-gluon degrees of freedom. In high energy nuclear collisions, intrinsic fluctuations, memory effects, and long-range color interactions can drive the fireball evolution away from purely Markovian thermalization, making nonextensive statistical descriptions relevant near equilibrium. We investigate the critical temperature of nonextensive hadron models using a pressure-based formulation derived from Tsallis entropy. Here we show that the qualitative structure of the pressure equation is controlled by both the nonextensive parameter q and the model-dependent bag contribution B^model . For q=0 , the pressure equations are monotonic and admit a unique positive root, whereas for q=1 the seventh-order term vanishes and analytic solutions can be obtained. For q>1 , the negative T^7 contribution modifies the pressure behavior and can generate multiple positive roots at finite volume. For q≥ 1 , T^model_c is ( 102.3≤ T_c^MIT≤ 106.1, 86.5≤ T_c^Dual≤ 87.8, and 113.1. . ≤ T_c^Fuzzy≤ 121.1) MeV. At q=0 , T^model_c ∼ 55 MeV marks the nuclear liquid–gas transition. A weighted comparison constrained by the MIT bag model at q=1 gives (T_c^w≈ 102) MeV , with Fuzzy and Dual QCD terms entering as model-propagation corrections. The interval (0.99≤ q≤ 1.002) therefore provides the most reliable domain for a common physical interpretation and a composite estimate of the critical temperature.
The double differential thick target neutron yields (TTNY) for 500 MeV/u 9 Be ions incident on a lead target were measured at emission angles from 0 degrees to 75 degrees using the time-of-flight (TOF) method with organic liquid scintillators. The angular distribution of neutron yields was obtained by integrating the neutron energy spectrum above the detection threshold. The experimental data were then compared with results calculated using the Monte Carlo simulation codes GEANT4, PHITS, and FLUKA with different physics models. The results show that the neutron energy spectrum in the forward direction exhibits a broad peak centered around 60-70% of the incident particle energy per nucleon and spread up to nearly twice the projectile energy per nucleon. All calculations overestimate the neutron yields near this broad peak except at 0 degrees, and overestimate the neutron energy corresponding to the peak center at all angles. The GEANT4 results show good agreement with the experimental data from a few tens of MeV to around 100 MeV at angles from 5 degrees to 60 degrees, while PHITS and FLUKA results slightly overestimate the yields. Regarding the angular distribution, the predictions from GEANT4, PHITS, and FLUKA differ from the experimental data by less than a factor of 2 except at 75 degrees.
The study of t+t cluster states in 6 He provides valuable insights into exotic nuclear structures and the behavior of fermionic cluster systems. This study shows rich cluster resonant structures above the threshold, observed experimentally and investigated theoretically. The excitation energy spectrum above the t+t threshold in 6 He is measured via the fragmentation excitation process during the breakup reaction of 9 Li on a 208 Pb target at an incident energy of 32.7 MeV/nucleon. The resonant states are reconstructed from the final state coincident particles t+t using the invariant mass method, while the non-resonant background is estimated using the event mixing method. Two structures are observed at excitation energies of Ex=14.0 +/- 0.3 and 15.0 +/- 0.3 MeV, both located above the t+t threshold at Ex similar or equal to 12.31 MeV. Microscopic cluster model calculations exploring the t+t resonant states in 6He yield theoretical energy spectra which are then compared with the current experimental results. The calculated reduced width amplitudes (RWA) of the t+t channels further support the presence of t+t clustering in the observed resonant structures.
We report new experimental cross sections for the 183 W(n, n' gamma ) and 183 W(n, 2n gamma ) reactions. This work aims to expand the experimental knowledge on neutron scattering reactions on tungsten isotopes, which are relevant for nuclear applications, including fusion reactor design. The results presented here were obtained using the GRAPhEME setup, located at the JRC-Geel GELINA facility. The measurement relies on prompt gamma -ray spectroscopy combined with neutron energy determination by time-of-flight. A full Monte Carlo analysis was employed, for the first time for a GRAPhEME data set, to obtain comprehensive uncertainties and covariance matrices. We compare the experimental cross sections with theoretical predictions from reaction model calculations. The data set presented here is significant for the understanding of nuclear reactions, and completes a previous similar study on 182,184,186 W.
