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\textbf{Background:} The influence of halo structure of $^6$He, $^8$B, $^{11}$Be and $^{11}$Li nuclei in several mechanisms such as direct reactions and fusion is already established, although not completely understood. The influence of the $^{10}$C Brunnian structure is less known. \textbf{Purpose:} To investigate the influence of the cluster configuration of $^{10}$C on the elastic scattering at an energy close to the Coulomb barrier. \textbf{Methods:} We present experimental data for the elastic scattering of the $^{10}$C+$^{208}$Pb system at $E_{\rm lab}$ = 66~MeV. The data are compared to the three- and the four-body continuum-discretized coupled-channels calculations assuming $^9$B+$p$, $^6$Be+$\alpha$ and $^8$Be+$p$+$p$ configurations. \textbf{Results:} The experimental angular distribution of the cross sections shows the suppression of the Fresnel peak that is reasonably well reproduced by the continuum-discretized coupled-channels calculations. However, the calculations underestimate the cross sections at backward angles. Couplings to continuum states represent a small effect. \textbf{Conclusions:} The cluster configurations of $^{10}$C assumed in the present work are able to describe some of the features of the data. In order to explain the data at backward angles, experimental data for the breakup and an extension of theoretical formalism towards a four-body cluster seem to be in need to reproduce the measured angular distribution.

The elastic scattering angular distributions for the system 7Li + 64Ni were measured in the bombarding energy range of 12 MeV ≤ E l a b ≤ 26.4 MeV . A phenomenological optical model analysis was performed for the measured data. The strengths of the fitted potential components at the surface were estimated to extract their variation with energy. Further analyses of the measured angular distributions were performed with a hybrid potential composed of a renormalized folded real and a phenomenological imaginary potential. Both the model potentials predict similar energy dependent behavior for the effective interaction potential around the barrier. Unlike the heavy targets, 7Li + 64Ni does not show a normal threshold behavior. It also does not clearly exhibit a behavior similar to 6Li + 64Ni. The real potential for 7Li + 64Ni does not exhibit any significant energy dependence and the imaginary potential strength remains almost independent of energy above the Coulomb barrier ( ∼ 14 MeV ). However, at energies below the barrier, a sudden drop in the imaginary potential strength is observed.

In this paper, we analyze the one-neutron pick-up from the 55Mn target when it is bombarded by 17MeV deuteron, by performing coupled reaction channel (CRC) calculations. Spectroscopic amplitudes for CRC calculations, and structural information such as reduced B(E2) transition probabilities, quadrupole, and magnetic momenta, are obtained from shell-model calculations using the fp-kb3 interaction. The calculated structure quantities are in good agreement with the available experimental data for both target and ejectile. Analyses of angular distributions show the relevance of microscopic information for the description of the higher excited states of 54Mn .

The incomplete fusion cross section of the 6Li + 28Si weakly bound system at above barrier energies was deduced from the measured $ \gamma$ -ray cross sections. The complete fusion cross section was estimated from the measured total fusion and incomplete fusion cross section and is found to be 85-100% of the total fusion cross section. The coupled channel calculation has been performed considering ground and first excited states of 28Si target. The fusion cross section estimated from coupled channel calculation shows good agreement with measured total fusion cross section at higher energies. The suppression of about 15% of the fusion cross section predicted by coupled channel calculation shows good agreement with the complete fusion cross section. The effect of the channel couplings on the elastic scattering angular distribution is also investigated.

Fusion excitation functions are measured for the system $^6$Li+$^{28}$Si using the characteristic $\gamma$-ray method, encompassing both the sub-barrier and above barrier regions, viz., $E_{lab}$= 7-24 MeV. Two separate experiments were performed, one for the above barrier region ($E_{lab}$= 11-24 MeV) and another for the below barrier region ($E_{lab}$= 7-10 MeV). The results were compared with our previously measured fusion cross section for the $^7$Li+$^{28}$Si system. We observed enhancement of fusion cross section at sub-barrier regions for both $^6$Li and $^7$Li, but yield was substantially larger for $^6$Li. However, for well above barrier regions, similar type of suppression was identified for both the systems., Comment: 8 pages, 6 figures, as accepted for publication in Eur.Phys.J.A

The elastic scattering for 6Li + 64Ni system was measured in the bombarding energy range of 13 MeV ⩽ E lab ⩽ 26 MeV . A phenomenological optical model analysis was performed and the behaviour of the surface strengths of the potential components with decreasing energy was extracted. A further analysis of the measured angular distributions, along with the existing data for 6Li + 58Ni, was performed with two different model potentials—one with the folded potential normalized with a complex factor (OMP1) and the other with a hybrid potential composed of a renormalized folded real and a phenomenological imaginary (OMP2) potential components. All the model potentials predict similar energy dependent behaviour for the interaction potential around the barrier. The observed energy dependence of the strengths of the real and imaginary potentials corroborate with the dispersion relation prediction for both the 6Li + 64Ni and 6Li + 58Ni systems. Though the evidence of breakup is distinct in the energy variation of the potential strengths, close to the barrier the variation is more in the line of conventional threshold anomaly. Also the threshold behaviour of the interaction potential does not indicate any distinct isotopic dependence.

Gamma ray spectra of two (p,γ) resonances have been utilised for the characterisation of the Clover detector at energies beyond 5 MeV. Apart from the efficiency and the resolution of the detector, the shapes of the full energy peaks as well as the nature of the escape peaks which are also very crucial at higher energies have been analysed with special attention. Proper gain matching in software have checked deterioration in the energy resolution and distortion in the peak shape due to addback. The addback factors show sharp increasing trend even at energies around 11 MeV.

The ${}^{26}\mathrm{Al}$ radioisotope is of great importance for understanding the chemical and dynamical evolution of our galaxy. Among the possible stellar sources, massive stars are believed to be the main producer of this radioisotope. Understanding ${}^{26}\mathrm{Al}$ nucleosynthesis in massive stars requires estimates of the thermonuclear reaction rates of the $^{26}\mathrm{Al}$${(n,p)}^{26}$Mg, $^{26}\mathrm{Al}$${(n,\ensuremath{\alpha})}^{23}$Na, and $^{23}\mathrm{Na}$${(\ensuremath{\alpha},p)}^{26}$Mg reactions. These reaction rates depend on the spectroscopic properties of ${}^{27}\mathrm{Al}$ states above the neutron and alpha thresholds. In this context, the $^{27}\mathrm{Al}$${(p,{p}^{\ensuremath{'}})}^{27}$Al* reaction was studied at 18 MeV using a high-resolution Enge Split-Pole spectrometer. States from the ground state up to excitation energies of $\ensuremath{\approx}$14 MeV were populated. While up to the ${}^{23}\mathrm{Na}$ + $\ensuremath{\alpha}$ threshold no additional states are observed, we report for the first time 30 new levels above the ${}^{23}\mathrm{Na}$ + $\ensuremath{\alpha}$ threshold and more than 30 new states above the ${}^{26}\mathrm{Al}$ + n threshold for which excitation energies are determined with an uncertainty of 4--5 keV.

The fusion excitation and elastic angular distribution were measured for 6,7 Li+28 Si from below to above Coulomb barrier (≤ 3Vb ) energies. The barrier distribution derived from the fusion data was found to be broad and asymmetric at the sub-barrier region, compared to 1D BPM estimation. Effect of rotational coupling on fusion was found to be not so dominant. Phenomenological optical potential parameters, with surface and volume type imaginary potentials, were obtained from f tting of elastic scattering data and energy dependence of real and imaginary surface strengths were investigated around the barrier. CDCC calculations considering only breakup of projectile were performed for 6,7 Li+28 Si with the elastic scattering data, using the code FRESCO. The effects of breakup of projectile on elastic cross section do not agree with the energy dependence of real and imaginary strength with volume type imaginary potential around the barrier.

The sub-barrier fusion excitation functions are measured for the first time for the system ${}^{7}\mathrm{Li}+ {}^{28}\mathrm{Si}$ by the characteristic \ensuremath{\gamma}-ray method in the energy range ${E}_{\mathrm{lab}}=7\text{\ensuremath{-}}11.5$ MeV. The results show an enhancement, below the barrier, by about a factor of two when compared with the one-dimensional barrier penetration (1D BPM) model. Introduction of coupling with the rotational ${2}^{+}$ state (1.779 MeV) of the target improves the fit somewhat, but still an enhancement of about 25--40% remains.

Elastic scattering angular distributions for 6Li+[Formula: see text]Si system were measured at [Formula: see text] and analyzed along with the existing data from the previous measurements in the energy range of [Formula: see text]. The measured cross-sections and the existing data, forming a set of angular distributions over a range of E/[Formula: see text], were analyzed using the phenomenological optical model potential (OMP). Three different sets of potential parameters were used. The energy dependence of the real and the imaginary potential strengths were, subsequently, extracted at the radius of sensitivity ([Formula: see text]) for the system. Continuum Discretized Coupled Channel (CDCC) calculation was performed to explore the contribution of projectile break-up (BU) on the observed energy dependence of the effective potential for elastic scattering of 6Li from [Formula: see text]Si. The energy variation of the strength of the real potential with continuum coupling was found to agree with the energy dependence of the same extracted from the (OMP) analysis at energies around the barrier. But the behavior of the imaginary strength appeared to be different. The calculated fusion cross-sections, including the effect of BU, clearly overestimated the measured fusion excitation function data in the below and near barrier energies but compared well with the data at higher energies.

Excitation functions for the above-barrier fusion cross sections are measured for the first time for the {sup 7}Li+{sup 28}Si system by two methods--the characteristic {gamma}-ray method and the evaporation {alpha} measurement method--in the energy range E{sub lab}=11.5-26 MeV. Experimental results are consistent and agree with each other, and the one-dimensional Barrier Penetration Model (BPM) predictions describe the data well up to twice the Coulomb barrier, but they overestimate the data by about 15-20% at higher energies.

Quasi-elastic-scattering and transfer reaction cross-section measurements were made for the {sup 7}Be+{sup 27}Al system at E{sub lab}=17, 19, and 21 MeV in the angular range {theta}{sub c.m.}=12 deg. An optical model (OM) analysis of the quasi-elastic scattering data was carried out. The fusion cross sections were derived at these energies by subtraction of the integrated transfer cross sections from the reaction cross sections obtained from the fits to quasi-elastic-scattering data. These fusion cross sections were found to be consistent with those obtained from the coupled-channels calculations. Elastic scattering and fusion cross sections were measured for the {sup 7}Li+{sup 27}Al system at E{sub lab}=10, 13, 16, 19, and 24 MeV. For elastic scattering the angular coverages were in the {theta}{sub lab}=12 deg. - 72 deg. range and for fusion the {alpha}-evaporation spectra from the compound nucleus were measured in the angular range {theta}{sub lab}=52 deg. - 132 deg. (142 deg. at 10 MeV). The elastic-scattering angular distributions were subjected to OM analysis. The {alpha}-evaporation spectra were reproduced with the statistical model calculations, and the fusion cross sections were extracted from them. The fusion cross sections were also extracted by subtraction of the integrated inelastic-scattering cross sections from the reaction cross sectionsmore » obtained from the OM fits to the elastic-scattering data, and these fusion data were found to be consistent. The CCDEF calculations describe these data quite well. A comparison of the fusion data for the {sup 7}Be+{sup 27}Al and {sup 7}Li+{sup 27}Al systems shows a similar and consistent behavior.« less