Reaction dynamics studies for the system 7Be + 208Pb at Coulomb barrier energies

The scattering process of the Radioactive Ion Beam 7 Be from a 208 Pb target was measured at three near-barrier energies. The quasi-elastic angular distributions were analyzed within the framework of the optical model to extract the reaction cross sections. The results are compared with those obtained for the reactions induced by the mirror projectile 7 Li and by the lightest particle-stable lithium isotope 6 Li on the same target. The angular distributions for the production of the two 7 Be constituent clusters, namely 3 He and 4 He, were also measured. In agreement with what observed for the interaction of 7 Be with lighter targets, the production of the heavier helium isotope resulted to be much more abundant than that of its lighter counterpart

Does the breakup process affect the reaction dynamics for the systems 17O, 17F + 58Ni at Coulomb barrier energies?

The scattering processes of two mirror projectiles, the well bound 17 O (Sn = 4.143 MeV) and the loosely bound radioactive 17 F (Sp = 0.600 MeV), on the proton closed shell target 58 Ni were measured at several energies around the Coulomb barrier. The experimental data were analyzed within the framework of the optical model to extract the reaction cross section and to investigate the role played by direct reaction channels at near-barrier energies. The comparison shows a similar behaviour for the two A = 17 projectiles despite their very different binding energies and suggests a rather small effect of the 17 F breakup channel on the reaction dynamics

ATHENA detector proposal - a totally hermetic electron nucleus apparatus proposed for IP6 at the Electron-Ion Collider

ATHENA has been designed as a general purpose detector capable of delivering the full scientific scope of the Electron-Ion Collider. Careful technology choices provide fine tracking and momentum resolution, high performance electromagnetic and hadronic calorimetry, hadron identification over a wide kinematic range, and near-complete hermeticity.This article describes the detector design and its expected performance in the most relevant physics channels. It includes an evaluation of detector technology choices, the technical challenges to realizing the detector and the R&D required to meet those challenges

ATHENA detector proposal — a totally hermetic electron nucleus apparatus proposed for IP6 at the Electron-Ion Collider

ATHENA has been designed as a general purpose detector capable of delivering the full scientific scope of the Electron-Ion Collider. Careful technology choices provide fine tracking and momentum resolution, high performance electromagnetic and hadronic calorimetry, hadron identification over a wide kinematic range, and near-complete hermeticity. This article describes the detector design and its expected performance in the most relevant physics channels. It includes an evaluation of detector technology choices, the technical challenges to realizing the detector and the R&D required to meet those challenges

Downstream Depolarization in the Sausage Relic: A 1-4 GHz Very Large Array Study

Radio relics are elongated sources related to shocks driven by galaxy cluster merger events. Although these objects are highly polarized at GHz frequencies (greater than or similar to 20%), high-resolution studies of their polarization properties are still lacking. We present the first high-resolution and high-sensitivity polarimetry study of the merging galaxy cluster CIZA J2242.8+5301 in the 1-4 GHz frequency band. We use the QU-fitting approach to model the Stokes I, Q, and U emission, obtaining best-fit intrinsic polarization fraction (p(0)), intrinsic polarization angle (chi(0)), rotation measure (RM), and wavelength-dependent depolarization (sigma(RM)) maps of the cluster. Our analysis focuses on the northern relic (RN). For the first time in a radio relic, we observe a decreasing polarization fraction in the downstream region. Our findings are possibly explained by geometrical projections and/or by decreasing of the magnetic field anisotropy toward the cluster center. From the amount of depolarization of the only detected background radio galaxy, we estimate a turbulent magnetic field strength of B-turb similar to 5.6 mu G in the relic. Finally, we observe RM fluctuations of about 30 rad m(-2) around the median value of 140.8 rad m(-2) at the relic position