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A comprehensive grid-based study of indoor Rn concentration in all accessible urban areas of the Republic of Cyprus, where 67.3% of the population resides, is presented. During the years 2004-2012, a total of 407 measurements of indoor Rn in the four highly-populated urbanised areas of Lefkosia, Lemesos, Larnaka, and Pafos districts were conducted, using high-sensitivity active Rn portable detectors. The four districts were subdivided into 189 grid cells, each of 1km2 in area. The grid cell mean indoor Rn concentration is in the range of 1.7 to 86.4Bq/m3, with an overall geometrical mean of 14.3±10.0Bq/m3, and a median of 14.3±3.9. The Rn mean in Cyprus is almost two-and-a-half times lower than the estimated world average of 39Bq/m3. The equivalent annual effective dose rate for each measurement was also calculated and compared to the corresponding world value. The spatial distribution and variation of Rn concentration values are also shown on maps of the urban areas of these districts. The conclusion of the present extensive and systematic Rn survey is that the Rn risk in the highly populated areas of Cyprus is low. © 2015 Elsevier B.V. 159 20 32

A systematic study of the indoor airborne radon concentration in the central part of the Nicosia district was conducted, using high-sensitivity active radon portable detectors of the type "RADIM3A". From a total of 108 measurements in 54 grids of 1 km^2 area each, the overall mean value is 20.6 \pm 13.2 Bq m^-3 (A.M.\pm S.D.). That is almost twice less than the corresponding average worldwide value. The radon concentration levels in drinking water were also measured in 24 sites of the residential district, using the high-sensitivity radon detector of the type "RADIM3W". The mean value obtained from these measurements is 243.8 \pm 224.8 mBq L^-1, which is relatively low compared to the corresponding internationally accepted level. The associated annual effective dose rates to each measurement were also calculated and compared to the corresponding worldwide values. From the geographical coordinates of the measuring sites and the corresponding radon concentration values, the digital radon map of the central part of the Nicosia district was constructed for the first time, by means of the ArcMap software package., Comment: 21 pages including 2 tables and 8 figures

The High Acceptance DiElectron Spectrometer (HADES) has been recently commissioned at GSI Darmstadt. It has been designed to study hadron properties inside nuclear matter via measurements of dielectron decays in proton, pion and heavy ion induced reactions in 1 - 2 AGeV energy range. We report first preliminary results on invariant masses of e+ e- pairs measured in 12C + 12C collisions at E = 2 AGeV and compare them to simulations based on UrQMD transport model. In summary we present and discuss planned experiments. © 2004 Elsevier B.V. All rights reserved. 749 1-4 SUPPL. 150c 159c Cited By :26

A comprehensive study was conducted to determine thorium, uranium and potassium elemental concentrations in surface soils throughout the accessible area of Cyprus using high-resolution gamma-ray spectrometry. A total of 115 soil samples was collected from all over the bedrock surface of the island based on the different lithological units of the study area. The soil samples were sieved through a fine mesh, sealed in 1000-mL plastic Marinelli beakers, and measured in the laboratory in terms of their gamma radioactivity for a counting time of 18 hours each. From the measured gamma-ray spectra, elemental concentrations were determined for thorium (range from 2.5x10^-3 to 9.8 micro g g-1), uranium (from 8.1x10^-4 to 3.2 micro g g-1) and potassium (from 1.3x10^-4 to 1.9 %). The Arithmetic mean values (A.M. +- S.D.) calculated are (1.2 +- 1.7) micro g g-1, (0.6 +- 0.7) micro g g-1, and (0.4 +- 0.3) %, for thorium, uranium and potassium, respectively, which are by a factor of three to six lower than the world average values of 7.4 micro g g-1 (Th), 2.8 micro g g-1 (U) and 1.3 % (K) derived from all data available worldwide. The best-fitting relation between the concentrations of Th and K versus U, and also of K versus Th, is essentially of linear type with a correlation coefficient of 0.93, 0.84, and 0.90, respectively. The Th/U, K/U, and K/Th ratios (slopes) calculated are equal to 2.0, 2.8x10^3,and 1.4x10^3, respectively., Comment: 24 pages including 3 tables and 4 figures; minor changes; accepted by J. of Environmental Radioactivity

A novel approach for a versatile first level dielectron trigger is presented. This trigger operates in the low multiplicity environment of nucleon-nucleon reactions as well as in the high multiplicity situation of nucleus-nucleus collisions. For optimal trigger performance, time of flight conditions for the two fastest particles of the event are combined with event multiplicity requirements. The dielectron trigger efficiency is given. The event reduction factor of such a trigger approach is studied for a low, a medium and a high multiplicity environment. The impact parameter dependence of the event reduction is given. The timing properties of the trigger signal are described. The losses due to deadtime are specified. Finally, the first level trigger rate is reported., documentstyle[epsfig]{elsart}, 28 pages, 12 postscript figures included; Accepted by Nucl. Instr. and Meth. A

774 1-4 940 941

We summarize the current status of e+e--coincidence experiments performed by the EPOS and ORANGE collaborations at GSI. © 1995. 583 C 237 246 Cited By :18

Using an active-shadow technique and a monoenergetic e+ beam at the high-flux reactor of ILL, we pursued the search for long-lived (> 5 × 10-13 s) neutral resonances that could be formed in e+e- scattering around an invariant mass of 1.8 MeV/c2. With a significantly improved experimental sensitivity we found no evidence for such a narrow resonance decaying into e+e- pairs. From our whole investigations, the model-independent stringent lower limits (95% CL) of 5 × 10-11 s and 1 × 10-10 s can be set on the lifetime of hypothetical J = 0 and J = 1 resonances, respectively. Our conclusive results rule out theoretical proposals that involve neutral free particles or e+e- bound states in this mass range, as an explanation of the e+e- lines observed at GSI. © 1991. 266 3-4 259 263 Cited By :30

A series of investigations on Bhabha scattering has been carried out in the last two years, searching for possible neutral resonances in the invariant mass range between 1.5 and 1.9 MeV/ c 2 , as motivated by the heavy-ion experiments at GSI. The currently highest sensitivity has been achieved by an experiment performed at ILL using the BILL β spectrometer to produce monoenergetic positrons and a high-resolution multidetector device. With systematic and statistical uncertainties of less than 0.25%, no evidence for any resonance was found around 1.8 MeV/ c 2 . The 97%-confidence upper limit on the intrinsic width and lifetime of a hypothetical spinless resonance is 1.9 meV and 3.5 × 10 −13 s, respectively, establishing the most stringent bound for new particles in this mass region.

The narrow positron lines emitted in U + Th and U + U collisions were investigated with respect to their dependence on the heavy-ion scattering angle Θp. For U + U collisions also the excitation function was measured which turned out to be flat from 5.7 to 6.2 MeV/u. These reaction characteristics are discussed in the framework of current models. © 1985. 162 4-6 273 276

The excitation function for Bhabha scattering was measured in the energy range between 760 and 840 keV (CM) in 1.4 keV steps with beams of monochromatic positrons scattered on a Be foil at angles between 79° and 101° (CM). The statistical accuracy was 0.5%. Up to an upper limit of 1.0 b eV/sr (CM) for the energy-integrated differential cross section (97% CL) no resonant scattering was observed. This limit corresponds to a maximal resonance contribution of 0.7% relatively to the Bhabha cross section, consistent with the upper bound, derived from precision measurements of the electron (g-2) factor. © 1988. 207 3 273 277 Cited By :31