RESUMO
The transverse momentum spectra of light nuclei (deuteron, triton and helion) produced in various centrality intervals in Gold-Gold (Au-Au), Lead-Lead (Pb-Pb) and proton-Lead (p-Pb) collisions, as well as in inelastic (INEL) proton-proton (p-p) collisions are analyzed by the blast wave model with Boltzmann Gibbs statistics. The model results are nearly in agreement with the experimental data measured by STAR and ALICE Collaborations in special transverse momentum ranges. We extracted the bulk properties in terms of kinetic freezeout temperature, transverse flow velocity and freezeout volume. It is observed that deuteron and anti-deuteron freezeout later than triton and helion as well as their anti-particles due to its smaller mass, while helion and triton, and anti-helion and anti-triton freezeout at the same time due to isospin symmetry at higher energies. It is also observed that light nuclei freezeout earlier than their anti-nuclei due to the large coalescence of nucleons for light nuclei compared to their anti-nuclei. The kinetic freezeout temperature, transverse flow velocity and kinetic freezeout volume decrease from central to peripheral collisions. Furthermore, the transverse flow velocity depends on mass of the particle which decreases with increasing the mass of the particle.
RESUMO
The yield of transverse momentum (pT) spectra of integrated hadrons and their ratios produced in pp collisions at 7 TeV are reported using DPMJET-III, EPOS1.99, EPOS-LHC, HIJING1.383, QGSJETII-04, and Sibyll2.3c models. The models' predictions are compared with the ALICE measurements obtained at mid rapidity and in the pT range from 0.3-6 GeV/c, 0.2-6 GeV/c, and 0.1-3 GeV/c for protons, kaons and pions respectively. Compared to the experimental data, the EPOS1.99 and EPOS-LHC models predict the yield of pion very well while reproducing yields of kaon and proton at low pT only. The DPMJET-III model predicts the yield of pions, kaons and protons only at intermediate value of pT. The HIJING and Sibyll models describe the integrated yield of pion well at high pT only. The QGSJETII model predicts the yield of kaon for almost the whole pT range. EPOS1.99 and Sibyll models reproduce excellent prediction of the K/π ratio over the entire range of pT whereas the EPOS-LHC, HIJING and DPMJET models underpredict with increasing order of discrepancy respectively. The EPOS1.99, EPOS-LHC, and Sibyll models predict the p/π ratio for low values of pT, but overpredict at high values, while the DPMJET-III and HIJING models underpredict over the entire range of pT. Although the models' predictions are mostly consistent with the ALICE measurements but none of the models completely describe the entire distribution for the integrated yield of hadron and their ratios.
RESUMO
A study was performed for the measurement of indoor radon concentration in two-storey houses in district Nowshera in the Khyber Pakhtunkhwa province of Pakistan. This area was not previously surveyed for such kind of study. The aim was to find some correlation of radon levels in first and second storey houses in the area. The measurements were carried out for 1 y from 1 December 2012 to 30 November 2013 using CR-39 detector. The area was divided into four parts, namely, Jhangera, Nowshera city, Akora Khattak and Pabbi. In the first storey houses, radon concentration ranged from 29 to 103 Bq m(-3) with the mean value of 64 ± 12 Bq m(-3) and that in the second storey houses ranged from 25 to 92 Bq m(-3) with the mean value of 56 ± 11 Bq m(-3). Relatively higher values of indoor radon levels in the first stories than the second stories were observed in all four parts of the study area. The effective doses received by the residents of the area were estimated for each part. The mean annual effective doses received by the inhabitants of the area from indoor radon ranged from 0.68 to 2.88 mSv with the mean value of 1.68 ± 0.32 mSv. The doses received by the people of the area were within the ICRP-65 recommended range (3-10 mSv).