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An experimental setup consisting of 12 layers of glass Resistive Plate Chambers (RPCs) of size 2 m × 2 m has been built at IICHEP-Madurai (9∘56 ′ 14.5 ′ ′ N 78∘0 ′ 47.9 ′ ′ E) to study the long term performance and stability of RPCs produced on a large scale in Indian industry. This setup has been collecting data triggered by the passage of charged particles. The measurement of the multiplicity of charged particles due to cosmic ray interactions are presented here. Finally, the results are compared with different hadronic models of the CORSIKA simulation. [ABSTRACT FROM AUTHOR]

The proposed 50 kton INO-ICAL experiment is an upcoming underground high energy physics experiment planned to be commissioned at Bodi hills near Theni, India *, ** to study various properties of neutrino oscillations using atmospheric neutrinos produced by extensive air shower phenomenon. The resistive plate chamber has been chosen as the active detector element for the proposed INO-ICAL. An experimental setup consisting a stack of 12 layers of glass resistive plate chambers each with a size of *** m has been built at IICHEP, Madurai to study the performance and long-term stability of the resistive plate chambers(RPCs) commercially produced in large quantities by the Indian industries as well as its electronics for the front-end and subsequent signal processing. In this study, the azimuthal dependence of muon flux at various zenith angles at Madurai **** and at an altitude of 160 m above mean sea level) has been presented along with the comparison of Monte Carlo from CORSIKA and HONDA predictions. [ABSTRACT FROM AUTHOR]

We are currently developing and studying the performance of glass RPC prototypes, under the INO detector R&D programme. While we were successful in building and characterising a large number of chambers using local glass, these have met with severe aging problems after a few months of continuous operation. We have then built a couple of RPCs using a Japanese glass. We report in this paper on our long term stability tests of these RPCs. We also present some of our recent results on tracking of cosmic ray muons in a stack of glass RPCs. [ABSTRACT FROM AUTHOR]

Proton and alpha particle spectra have been measured in the 12C+93Nb and 12C+58Ni reactions at E(12C) 40 and 50 MeV and in the 16O+93Nb reaction at E(16O) = 75 MeV. The spectra are compared with the statistical model calculations. The shapes of the calculated spectra are in agreement with experimental data except for the alpha spectrum in the 12C+93Nb reaction at 40 MeV. The observed evaporation bump is at ∼2 MeV lower energy compared to the calculated one. This discrepancy could imply alpha particle emission from a deformed configuration before compound nucleus formation at this near Coulomb barrier beam energy. [ABSTRACT FROM AUTHOR]

The isotope 124Sn enriched to better than 50% is needed in substantial quantity as detector material for the proposed neutrinoless double beta decay (0νββ) experiment in India (TIN.TIN). Present work investigates isotope-selective laser photoionization scheme for 124Sn. Transition to the first excited state from the ground state lies at 286.3 nm having short lifetime (~ 5 ns) and isotope shift (IS), Δν(124-120) = 441 MHz. However, the availability of high repetition rate (kHz), narrowband tunable pulsed laser in UV with low temporal jitter is a technological impediment for achieving isotopic selectivity in this transition. An alternate three-color photoionization scheme is proposed for separation of 124Sn. Laser vaporization of tin followed by supersonic expansion in a molecular beam apparatus provided the tin atomic beam. Tin atoms were first excited to the 5p6s,3P1 state from the 5p2,3P0 ground state by a broadband pulsed dye laser (λ1 = 286.3 nm). Isotopic selectivity was achieved in the second excitation step at λ2 = 855.2 nm by a narrowband continuous wave laser. Subsequently, resonant photoionization at λ3 = 694.7 nm to a newly observed autoionizing state at 60,992.9 cm−1 provided efficient photoionization. The IS for all even and hyperfine splitting for odd isotopes have been measured for the 855.2 nm transition. A selectivity factor of 24 is achieved for 124Sn isotope. The absorption cross sections of the three excitation steps is reasonably high to have an efficient photoionization scheme. [ABSTRACT FROM AUTHOR]