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Barrier distribution for the 28Si+154Sm system has been extracted from large angle quasielastic scattering measurement to investigate the role of various channel couplings on fusion dynamics. The coupled channel calculations, including the collective excitation of the target and projectile, are observed to reproduce the experimental BD rather well. It seems that the role of neutron transfer, relative to collective excitation, is in fact weak in the 28Si+154Sm system even though it has positive Q-value for neutron transfer channels.

Mass angle distribution measurements for 19F+238U reaction were carried out around the sub barrier energies. Mass angle correlation has not been observed at above and below the fusion barrier in present reaction. This infer the minimal presence of non compound like events at these bombarding energies range.

Fission excitation functions for 19F + 194,196,198Pt reactions populating 213,215,217Fr compound nuclei are reported. Out of these three compound nuclei, 213Fr is a shell closed (N=126) compound nucleus and the other two are away from the shell closure. From a comparison of the experimental fission cross-sections with the statistical model predictions, it is observed that the fission cross-sections are underestimated by the statistical model predictions using shell corrected finite range rotating liquid drop model (FRLDM) fission barriers. Further the FRLDM fission barriers are reduced to fit the fission cross-sections over the entire measured energy range.

We plan to perform large angle quasi-elastic scattering experiments using a 28Si beam on heavy targets in order to study the nuclear dynamics and structure effects. As a prelude to our first test experiment with a 154Sm target, we study here the existing fusion data for the same system through the barrier distribution.

The triton angular distribution in the 12C(7Li,t)16O reaction has been measured at 20 MeV incident energy. Comparison of the data with Finite Range DWBA and CDCC-CRC calculations show that breakup coupling effects are prominent in the transfer to the ground state. This observation is similar to that in the 12C(6Li,d) reaction at the same incident energy. The alpha spectroscopic factor of the 16O ground state is determined (Sα=0.25) from a comparison of the measured angular distribution with respect to the CDCC-CRC calculations. The E2 S-factor of the 12C(α,γ) reaction at 300 keV in the framework of a potential model is determined to be about 118 keV-barn.

The pre- and post-scission neutron multiplicities have been extracted for the 220,222,224Th nuclei for the excitation energy range of 40 MeV to 64 MeV using the National Array of Neutron Detectors (NAND). The Th isotopes are populated from the fusion reaction of 16O+204,206,208Pb systems in order to investigate the dynamics of fusion-fission reactions using the neutron multiplicity as a probe. The theoretical calculations were performed using the Bohr-Wheeler fission width as well as the dissipative dynamical fission width from Kramers prescription. It is observed that the Bohr-Wheeler fission width underestimates the pre-scission yields to a large extent. A large amount of dissipation is required in the Kramers width to fit the observed pre-scission neutron multiplicities.

We present the evolution of giant dipole resonance (GDR) width as a function of angular momentum in the compound nucleus 144Sm in the temperature range of 1.5-2.0 MeV. The high energy γ rays emitted from the decay of excited 144Sm were measured using large NaI detector in coincidence with 4π sum spin spectrometer. GDR widths were found to comply with thermal shape fluctuation model in this temperature range over a wide range of spin. Experimental widths tend to increase rapidly at high angular momentum values.

The reaction mechanism of 19F + 232Th and 28Si + 232Th systems populating the near-super-heavy compound nuclei 251Es and 260Rf respectively are investigated using neutron multiplicity as a probe. The prescission neutron multiplicities of these compound nuclei are calculated at different excitation energies using a statistical model code. These calculations are performed using the Bohr-Wheeler transition state fission width as well as the dissipative dynamical fission width based on the Kramers’ prescription. For 19F + 232Th system, the measured yield of pre-scission is compared with the statistical model calculations for the decay of a compound nucleus in the excitation energy range of 54-90 MeV. The comparison between the measured and the calculated values indicates that the Bohr-Wheeler fission width underestimates the pre-scission neutron yield and a large amount of dissipation strength is required to reproduce the experimental pre-scission neutron multiplicities. The excitation energy dependence of the fitted values of the dissipation coefficient is also discussed. In addition, exploratory statistical model calculations of pre-scission neutron multiplicity for the 28Si + 232Th system are presented in the above range of excitation energy.

This paper report the summary of the experimental results of pre-scission neutron multiplicities from four compound nuclei, namely 210,212,214,216Rn, and statistical model analysis of the corresponding data. The compound nuclei 210,212,214,216Rn having N/Z values as 1.441, 1.465, 1.488, 1.511 respectively are populated through the 16,18O+194,198Pt reactions at excitation energies of 50, 61, 71.7 and 79 MeV. The measured neutron multiplicities are further analyzed with the statistical model of nuclear decay where fission hindrance due to nuclear dissipation is considered. The N/Z dependence of the dissipation strength at lowest excitation energy of the compound nuclei suggests shell closure effects. However, such effects are not observed at higher excitations where the variation of the dissipation strength with N/Z does not show any specific trend. The variation of N/Z in fission time scale is also shown.

Exclusive measurement of giant dipole resonance (GDR) γ rays has been performed in 144Sm nucleus which was populated at near barrier energy using the heavy ion reaction of 28Si beam on 116Cd target. GDR γ rays were detected in coincidence with low energy γ rays using 32 elements 4π sum-spin spectrometer. The 144Sm nucleus was populated at an excitation energy of 68 MeV in the temperature range of 1.1-1.3 MeV. The measured GDR widths in this temperature range are consistent with the Kusnezov’s parametrization.

Fission fragment (FF) angular distributions for 6,7Li+235,238U reactions and mass distributions for 6,7Li+238U reactions have been measured at energies near and above the Coulomb barrier. The angle integrated fission cross sections for 6Li induced reactions at sub-barrier energies are found to be higher than 7Li induced reactions possibly due to larger contribution of breakup induced fission in case of the former compared to the latter. The FF anisotropy for 6,7Li+235U was found to be smaller than 6,7Li+238U, manifesting the effect of target ground state spin. The statistical saddle point (SSP) model predictions were found to be consistent with the measured FF anisotropy for 6,7Li+235U, however they were under-estimated for 6,7Li+238U particularly at lower energies. Observation of larger FWHM of FF folding angle distribution and sharp increase in peak to valley ratio for FF mass distribution with the decrease in bombarding energy in 6,7Li+238U reactions confirms the presence of breakup induced fission.

Neutron multiplicity measurements are carried out for the 19F + 194,196,198Pt systems at excitation energy range of 48 to 67.5 MeV. Out of these three compound nuclei (CN) 217Fr, 215Fr and 213Fr, one of the CN (213Fr) has neutron shell closure (NC=126). Experimentally obtained neutron multiplicities are compared with the standard statistical model predictions. It has been observed that the standard statistical model under-predicts the experimental pre-scission neutron multiplicities values. Also the comparison of pre-scission neutron multiplicities for different compound nuclei (CN) indicates the signature of shell effects on nuclear dissipation, which results in the lowering of the pre-scission neutron multiplicities.

Fission fragment mass distributions for 19F+184W have been measured at beam energies in the range of 85 - 125 MeV. Analysis of mass distribution width indicates that the system proceeds towards the formation of compound nucleus. No signature of quasifission is observed in this reaction. These results strengthen the conclusions of our earlier works revealing the stabilizing effect of the Z = 82 shell closure against fission.

Evaporation residue (ER) excitation function in the complete fusion of 16O with 194Pt is measured around the Coulomb barrier using gas-filled mode of the HYbrid Recoil mass Analyser (HYRA) at the Inter University Accelerator Centre (IUAC), New Delhi. Measured ER excitation function is compared with statistical model calculation. Nuclear dissipation strength β = 1.5 is required to explain the experimental data at higher excitation energies.

Learning disabilities (LD) are problem that influence the brain capacity to receive, process, analyse and store information. These processing issues can interfere with learning fundamental abilities, for example, reading (Dyslexia), writing (Dysgraphia) and math (Dyscalculia). Fortunately, in today's world technology, we have numerous option techniques for educating and supporting fundamental skills in reading, writing and math such as mobile learning by using mobile app. However, the research in mobile app design model for Dyscalculia children is still scarce: very few studies have focus on how to design and develop appropriate mobile app for Dyscalculia children from the perspective of mobile app designers and developers. The purpose of this paper is to identify the appropriate components that should be included in the mobile app model. Interview sessions were conducted with Dyscalculia practitioners that involved a teacher, paediatric and an educational psychology. This has resulted in identifying 16 components that can be included in the mobile app design model.

Fission process is strongly influenced by entrance channel dynamical variables. Among these, the nuclear charge product, mass asymmetry and deformation play important role in fission dynamics. Reaction characteristics are distinguished by investigating the properties of fission mass and angular distributions. Experiments using actinide targets are challenging due to many conflicting results making unambiguous identification of quasi-fission difficult. At IUAC accelerator facility many experiments have been performed to make a systematic study of fission mechanism and role of entrance channel parameters and deformation. Fragment mass distribution, angular distribution and neutron multiplicity measurements are performed to study reactions using spherical and deformed targets.

Femoral neck stress fracture (FNSF) is an uncommon but potentially serious orthopaedic problem. This is a case report on missed femoral neck stress fracture in a 62-year-old female who was initially treated as early-onset coxarthrosis. She later presented to us with a displaced intra-capsular neck of left femur fracture and underwent total hip replacement. This case illustrates that causes other than osteoarthritis should be taken into consideration in patients presenting with anterior hip pain where symptoms are disproportionate to clinical and radiological findings. More advanced investigations such as MRI scan or regular follow up with plain radiographs should be performed. A delay in diagnosis can lead to secondary displacement of the femoral neck stress fracture.