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Mass and total kinetic-energy (TKE) distributions of fission fragments from $^{257}\mathrm{Md}$ nucleus populated by complete fusion of $^{19}\mathrm{F}$ with $^{238}\mathrm{U}$ have been measured in the range of excitation energy ${E}^{*}\ensuremath{\approx}37\text{\ensuremath{-}}48\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$. Due to the skewness of the measured TKE distributions, two Gaussian distributions were required to explain the data. The events with high TKE must originate from the supershort mode of fission, the presence of which has been confirmed by measuring two additional reactions: $^{19}\mathrm{F}+^{232}\mathrm{Th}$ and $^{18}\mathrm{O}+^{238}\mathrm{U}$ involving first a different target and then a different projectile leading to compound nuclei $^{251}\mathrm{Es}$ and $^{256}\mathrm{Fm}$, respectively, at similar excitation energies and comparing their mass-TKE correlation plots. The existence of considerable supershort mode of fission for the $^{257}\mathrm{Md}$ nucleus up to ${E}^{*}\ensuremath{\approx}48$ MeV, observed for the first time, reveals that such rare fission modes for neutron-rich exotic nuclei are far off from the liquid drop model predictions, even at high excitation energies.

In order to investigate the interplay between nuclear structure (shell closure) and dynamics, fission fragment mass distributions have been measured for reactions $^{35,37}\mathrm{Cl}+^{206,208}\mathrm{Pb}$. These reactions have similar entrance channel parameters except for the number of closed shell configuration in the entrance channel. Fission fragment mass distributions have been measured for these reactions in the energy region close to the Coulomb barrier. No mass-angle correlation was observed in any of the four reactions, indicating the absence of fast quasifission (QF), but mass distributions were wider than that of compound nucleus (CN) fission, which indicates the presence of slow QF. With comparable fissility and deformation values, extra stability against QF was observed for reactions which have more closed shell configurations in the entrance channel. Mass-angle distributions of these reactions do not follow the systematics with respect to mean fissility. A new systematics has been obtained by considering quadrupole deformation of the heavy reaction partner along with the fissility, which explains the absence of mass-angle correlation in the presently measured reactions.

The neutron energy spectra in coincidence with both the correlated fission fragments in $^{32}\mathrm{S}+^{184}\mathrm{W}$ reaction forming the compound nucleus $^{216}\mathrm{Th}$ at an excitation energy of 71.31 MeV have been measured at various angles with respect to one of the fission fragments. Pre- and post-scission neutron multiplicities of $2.68\ifmmode\pm\else\textpm\fi{}0.48$ and $3.3\ifmmode\pm\else\textpm\fi{}0.20,$ respectively, have been extracted by analyzing angular correlation of the neutron energy spectra using moving source fitting procedure. The excess pre-scission neutron multiplicity in comparison to statistical model joanne2 code predictions have been converted into total fission delay. A comparative study of fission delay has been carried out for the $^{16}\mathrm{O}+^{208}\mathrm{Pb}$ reaction forming the compound nucleus $^{224}\mathrm{Th}$ at similar excitation energy as in $^{32}\mathrm{S}+^{184}\mathrm{W}$ reaction. Both the reactions have been analyzed within the frame work of joanne2 code including fission delay, deformation dependent level densities, particle binding energies, and transmission coefficients. The observed fission delay for both the reactions can be quantitatively understood if different formation time predicted by dynamical model hicol code are considered.

Quasi-elastic scattering measurements have been performed using 16O and 24Mg projectiles off 90Zr at energies around the Coulomb barrier. Experimental data have been analyzed in the framework of coupled channels (CC) calculations using the code CCFULL. The quasi-elastic scattering excitation function and derived barrier distribution for 16O + 90Zr reaction are well reproduced by the CC calculations using the vibrational coupling strengths for 90Zr reported in the literature. Using these vibrational coupling strengths, a Bayesian analysis is carried out for 24Mg + 90Zr reaction. The β 2 and β 4 values for 24Mg are determined to be + 0.43 ± 0.02 and − 0.11 ± 0.02 , respectively. The β 2 parameter determined in the present work is in good agreement with results obtained using inelastic scattering probes. The hexadecapole deformation of 24Mg has been measured very precisely for the first time. Present results establish that quasi-elastic scattering could provide a useful probe to determine the ground state deformation of atomic nuclei.

The $^{54}\mathrm{Mn}^{*}$ (surrogate of $n+^{53}\mathrm{Mn}$) and $^{61}\mathrm{Ni}^{*}$ (surrogate of $n+^{60}\mathrm{Ni}$) compound systems have been populated at overlapping excitation energies by transfer reactions $^{52}\mathrm{Cr}(^{6}\mathrm{Li},\ensuremath{\alpha})^{54}\mathrm{Mn}^{*}$ at ${E}_{\mathrm{lab}}=33.0\phantom{\rule{0.28em}{0ex}}\mathrm{MeV}$ and $^{59}\mathrm{Co}(^{6}\mathrm{Li},\ensuremath{\alpha})\phantom{\rule{0.16em}{0ex}}^{61}\mathrm{Ni}^{*}$ at ${E}_{\mathrm{lab}}=40.5\phantom{\rule{0.28em}{0ex}}\mathrm{MeV}$, respectively. The proton decay probabilities of the compound systems have been determined by measuring evaporated protons at backward angles in coincidence with projectilelike fragments detected around the grazing angle. The $^{53}\mathrm{Mn}(n,xp)$ cross sections in the equivalent neutron energy range of 8.2--16.4 MeV have been determined within the framework of the surrogate reaction ratio method using $^{60}\mathrm{Ni}(n,xp)$ cross-section values from the literature as a reference. The measured $^{53}\mathrm{Mn}(n,xp)$ cross-section values are found to be consistent with the predictions of the talys-1.8 statistical model code using microscopic level densities and results of various evaluated nuclear data libraries: eaf-2010, rosfond-2010, and jeff-3.3 within the experimental uncertainties.

Background: A transparent approach for the study of nuclear shapes and sizes in excited states requires knowledge about dynamic deformations of both neutron and proton distributions, by means of their independent excitations at the same energy. Heavy-ion scattering could be a reliable approach, facilitating a simultaneous study of deformations of charge and matter densities in nuclei.Purpose: Measurement of angular distributions of the inelastic scattering cross sections for excitations to low-lying ${2}_{1}^{+}$ and ${3}_{1}^{\ensuremath{-}}$ states in $^{112,116,118,120,122,124}\mathrm{Sn}$ nuclei using $^{12}\mathrm{C}$ beam as a probe at ${E}_{\mathrm{lab}}=60\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$, and determination of neutron and proton transition matrix elements involved in each excitation.Methods: Projectilelike fragments have been detected using ten sets of Si-surface barrier detector telescopes to measure the cross sections for elastic and inelastic scattering channels. Coupled reaction channels calculations are performed to understand the measured differential cross sections.Results: Homogeneous nature of surface vibrations (similar deformation for proton and neutron distributions) for the ${2}_{1}^{+}$ and ${3}_{1}^{\ensuremath{-}}$ states in Sn isotopes is observed.Conclusions: A comparison with recent results using $^{7}\mathrm{Li}$ projectile at similar ${E}_{\mathrm{c}.\mathrm{m}.}/{V}_{\mathrm{B}}$, which showed damped neutron vibrations particularly for the ${3}_{1}^{\ensuremath{-}}$ state, confirms that such measurements are probe dependent. Intrinsic transition matrix elements of nuclei can be deduced by removing the effects of finite projectile size in the extraction of nuclear shapes.

Prominent enhancement in the room temperature electrical conductivity of spin-coated poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) thin films has been achieved after treatment with various acids. The conductivity of PEDOT:PSS films could be enhanced from 0.6[Formula: see text]S/cm to over 3300[Formula: see text]S/cm after treatment with trifluoromethanesulfonic acid i.e., by a factor of 5500. It is noteworthy that the conductivity enhancement is nonmonotonic with respect to acid concentration i.e., the magnitude of increase in the conductivity exhibited a strong dependence over the molarity of acids. The possible reason of the conductivity enhancement is the improvement of nanoscale connectivity between the conducting PEDOT chains after acid treatment that results in highly conductive film. The improvement in the nanoscale connectivity is caused due to the loss of PSS from the PEDOT:PSS films after acid treatment that is confirmed through atomic force microscopy and X-ray photoelectron spectroscopy.