Role of the cluster structure of 7^7Li in the dynamics of fragment capture

Exclusive measurements of prompt $\gamma$-rays from the heavy-residues with various light charged particles in the $^7$Li + $^{198}$Pt system, at an energy near the Coulomb barrier (E/$V_b$ $\sim$ 1.6) are reported. Recent dynamic classical trajectory calculations, constrained by the measured fusion, $\alpha$ and $t$ capture cross-sections have been used to explain the excitation energy dependence of the residue cross-sections. These calculations distinctly illustrate a two step process, breakup followed by fusion in case of the capture of $t$ and $\alpha$ clusters; whereas for $^{6}$He + $p$ and $^{5}$He + $d$ configurations, massive transfer is inferred to be the dominant mechanism. The present work clearly demonstrates the role played by the cluster structures of $^7$Li in understanding the reaction dynamics at energies around the Coulomb barrier.Comment: 6 pages, 4 figures, Accepted for publication in Phys. Letts.

Fusion of 6^{6}Li with 159^{159}Tb} at near barrier energies

Complete and incomplete fusion cross sections for $^{6}$Li+$^{159}$Tb have been measured at energies around the Coulomb barrier by the $\gamma$-ray method. The measurements show that the complete fusion cross sections at above-barrier energies are suppressed by $\sim$34% compared to the coupled channels calculations. A comparison of the complete fusion cross sections at above-barrier energies with the existing data of $^{11,10}$B+$^{159}$Tb and $^{7}$Li+$^{159}$Tb shows that the extent of suppression is correlated with the $\alpha$-separation energies of the projectiles. It has been argued that the Dy isotopes produced in the reaction $^{6}$Li+$^{159}$Tb, at below-barrier energies are primarily due to the $d$-transfer to unbound states of $^{159}$Tb, while both transfer and incomplete fusion processes contribute at above-barrier energies.Comment: Phys. Rev. C (accepted

Investigation of complete and incomplete fusion in 7^{7}Li+124^{124}Sn reaction around Coulomb barrier energies

The complete and incomplete fusion cross sections for $^{7}$Li+$^{124}$Sn reaction were measured using online and offline characteristic $\gamma$-ray detection techniques. The complete fusion (CF) cross sections at energies above the Coulomb barrier were found to be suppressed by $\sim$ 26 \% compared to the coupled channel calculations. This suppression observed in complete fusion cross sections is found to be commensurate with the measured total incomplete fusion (ICF) cross sections. There is a distinct feature observed in the ICF cross sections, i.e., $\textit{t}$-capture is found to be dominant than $\alpha$-capture at all the measured energies. A simultaneous explanation of complete, incomplete and total fusion (TF) data was also obtained from the calculations based on Continuum Discretized Coupled Channel method with short range imaginary potentials. The cross section ratios of CF/TF and ICF/TF obtained from the data as well as the calculations showed the dominance of ICF at below barrier energies and CF at above barrier energies.Comment: 9 pages, 8 figure

Small Quadrupole Deformation for the Dipole Bands in 112In

High spin states in $^{112}$In were investigated using $^{100}$Mo($^{16}$O, p3n) reaction at 80 MeV. The excited level have been observed up to 5.6 MeV excitation energy and spin $\sim$ 20$\hbar$ with the level scheme showing three dipole bands. The polarization and lifetime measurements were carried out for the dipole bands. Tilted axis cranking model calculations were performed for different quasi-particle configurations of this doubly odd nucleus. Comparison of the calculations of the model with the B(M1) transition strengths of the positive and negative parity bands firmly established their configurations.Comment: 10 pages, 11 figures, 2 table

Systematic investigation of channel coupling effects on elastic, inelastic and neutron transfer channels in 6^6Li+159^{159}Tb

Elastic scattering angular distribution for weakly bound nucleus $^{6}$Li on the deformed rare earth $^{159}$Tb target nucleus has been measured at energies around the Coulomb barrier. The elastic scattering cross sections for this reaction consist of inelastic contributions from low lying excited states of $^{159}$Tb. The pure elastic cross-sections have been extracted from the admixture of elastic and inelastic data. The optical model potential parameters for the system have been obtained from the extracted pure elastic scattering cross sections. Coupled channel calculations have been performed with this set of potential parameters, to compare the theoretical and experimental inelastic scattering cross sections. The work has been extended to obtain the spectroscopic factor for $^{158}$Tb+n configuration from the experimental 1n-pickup data

COVID‑19 pneumonia imaging follow‑up: when and how? A proposition from ESTI and ESR

Abstract This document from the European Society of Thoracic Imaging (ESTI) and the European Society of Radiology (ESR) discusses the role of imaging in the long-term follow-up of COVID-19 patients, to define which patients may benefit from imaging, and what imaging modalities and protocols should be used. Insights into imaging features encountered on computed tomography (CT) scans and potential pitfalls are discussed and possible areas for future review and research are also included. Key Points • Post-COVID-19 pneumonia changes are mainly consistent with prior organizing pneumonia and are likely to disappear within 12 months of recovery from the acute infection in the majority of patients. • At present, with the longest series of follow-up examinations reported not exceeding 12 months, the development of persistent or progressive fibrosis in at least some individuals cannot yet be excluded. • Residual ground glass opacification may be associated with persisting bronchial dilatation and distortion, and might be termed “fibrotic-like changes” probably consistent with prior organizing pneumonia.publishedVersio

Near barrier scattering of 8He on 208Pb

The exotic nucleus 8He is investigated by means of the measurement of the angular distributions of the elastic channel and the 6He and 4He fragment yields produced in the collision with a 208Pb target at two energies around the Coulomb barrier, 16 and 22 MeV. The experiment was performed at the GANIL-SPIRAL facility, with the aim of extracting information about the structure of 8He and the relevant reaction mechanisms. In this contribution, details of the experimental setup and preliminary data on elastic cross sections are reported