[en] Medical Internal Radiation Dosimetry formalism has been implemented for a liquid source by establishing CR 39 SSNTD based alpha spectroscopy. The alpha tracks were isolated by establishing track diameter-brightness correlation. The equilibrium dose has been estimated by convoluting the obtained equilibrium alpha spectrum with corresponding stopping powers. (author)

[en] Internal radiation dose formalism, derived from the equation of continuity, is one of the formalisms for interpreting radiation stress corrosions in critical systems, radiotherapy using α emitting isotopes etc. Implementation of this formalism requires the measurement of α spectrum at the points of interest. This is challenging for practical situations as the source is spread in the medium. The current method is providing an energy resolution of 250 keV FWHM corresponding to 5.54 MeV α peak from ²⁴¹Am alpha source. The currently measured alpha spectrum at the center of the thorium nitrate solution along with Geant4 simulation is shown in the article. This shows the 4.04 MeV α peak is well resolved and the continuum transition of α in the flood medium is well identified. Further the Geant4 simulation is also showing a well agreement with the current measurement. This shows the current spectroscopy method provides an accurate spectral information and is well acceptable for the internal dosimetry, which can be applied in the fields of medical, and other radiation-critical situations

[en] Here, we report the development of an innovative method for the direct measurement of neutron energy spectra, using CR-39 SSNTD as a passive detector. Neutrons produced from Am-Be source is used for the measurement. 5.48 MeV α particle from the ²⁴¹Am source undergo fusion with ⁹Be to form the compound nucleus of ¹³C at an excitation energy of around 14.4 MeV. Depending on the thickness of Be the excitation energy of ¹³C may vary from 10.6 MeV to 14.4 MeV. Neutron from such resonance populate various states of ¹²C depending on the structure of states. The expected neutron spectrum from Am-Be were measured using CR-39 detector from University of Calicut. The neutron energy spectrum thus obtained analyzed using the simulated spectrum from nuclear reaction code EMPIRE 3.2, Alpha straggling and tunnelling affected to spectrum is also taken in to consideration

[en] Proton dose gradient effects in the proton dosimetry situation are studied analytically using one-speed diffusion equation. Dose distribution has been studied for pure coulombic and coulombic plus nuclear interaction conditions. This results in the violation of the equation of continuity and Bragg gray cavity theory. (author)

[en] Research in low-energy nuclear physics demands low-energy charged particle beams with lower energy spread and lower emittance. The production of high current beams with lower emittance is an open problem, till now in the field of accelerator physics. Understanding the requirements of nuclear astrophysics and other low energy applications, a novel ion source design has been developed to meet the demands of high current with lower energy spread and emittance. This has been achieved through a hybrid ion source design having a combined ECR Glow discharge mode of operation. The ECR modes have been generated with a TEM01 class rectangular waveguide design. Further the plasma is confined into a small volume by the externally configured magnetic field. The emittance blow up has been reduced by applying the background gas injection in perpendicular to the beam direction. The details are discussed herein

[en] The low energy nuclear reactions producing extreme low energy neutrons in the exit channel have a renewed interest due to their larger involvement in nuclear astrophysics and radiation dosimetry. Most of the reactions in this range belongs to direct reactions only and those neutrons are not accompanied by any γs. The unfolded spectrum of neutrons, compared with the theoretical spectrum. This shows that the spectrum is similar and the low energy with a starting point of 100 keV is well measured. The experiment shows that this method clearly discriminates low energy neutrons and γs and can be effectively utilized for the situations of nuclear astrophysics where low energy neutrons in the exit channel are present

[en] Proton therapy for cancer treatment gained significant attention due to its high conformity towards dose deposition. Proton therapy is performed by utilizing high-energy proton beams up to 250 MeV. The current study incorporated the direct and pre-equilibrium components of nuclear reactions, along with the compound nuclear component. The statistical calculations are optimized based on the available experimental residue cross sections. Our study is confined to nuclear reactions and Rutherford scattering is not accounted. However it is also contributing much to out of field dose since it’s cross section is high compared to the nuclear reaction cross sections. The current study is limited to theoretical only, an accurate measurement on double differential cross sections is required for an accurate determination of the out of field contribution

[en] Measurement of neutrons in the high gamma background is difficult because of the extremely large number of photon events and the pulsed nature of the accelerator beam. The high instantaneous beam intensity hampers the use of detectors with active readout, because of pile–up effects in the electronics. It may also cause radiation damage to the detector. Hence, most of the active detectors and tracking type of detectors fails in measuring the neutron spectrum in high gamma background. The neutron spectrum over the energy 0.7-10 MeV are recorded. The efficiency corrected neutron spectrum generated from the proton recoil events, through two body kinematics is presented in the article, along with Talys-1.96 (γ,n) calculate spectrum. This shows a good agreement between the experimental and theoretical spectra. The present method is successful in the measurement of neutron spectrum with reasonable sensitivity, achieved by removing the ’dark tracks’. This method can be utilized for the measurement of neutrons in the mixed high intensity radiation field