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American Mineralogist, Volume 100, pages 973–982, 2015 0003-004X/15/0004–973$05.00/DOI: http://dx.doi.org/10.2138/am-2015-4874 973 THE SECOND CONFERENCE ON THE LUNAR HIGHLANDS CRUST AND NEW DIRECTIONS Revised mineral and Mg# maps of the Moon from integrating results from the Lunar Prospector neutron and gamma-ray spectrometers with Clementine spectroscopy† Sarah T. CriTeS1,* and Paul G. luCey1 1Hawai’i Institute of Geophysics and Planetology, University of Hawai’i at Mānoa, 1680 East West Road, POST 602, Honolulu, Hawaii 96822, U.S.A. abSTraCT

Radioactivity of some building and raw materials used in Croatia

In the present study, the activity concentrations of 226Ra, 232Th, 40K in some building and raw materials used in Croatia were measured by using a gamma-ray spectrometer with the HPGe detector. The average activity concentrations of the studied different building and raw materials ranged from 11.6 ± 1.7 (concrete) to 251.2 ± 25.7 Bqkg-1 (GBFS), 14.0 ± 2.7 (concrete) to 54.4 ± 8.3 (coal fly ash) and 147.2 ± 19.0 (concrete) to 773.7 ± 82.0 Bqkg-1 (tuff) for 226Ra, 232Th and 40K, respectively. Radium equivalent activity, activity concentration index, absorbed gamma dose rate indoor due to the external exposure and corresponding annual effective dose were determined to estimate the exposure risk arising due to the use of these building and raw materials.

-collimated configuration with mono-energetic proton beams of 165 MeV and 224 MeV, respectively. Results acquired by means of trans- versal PGS at different phantom depths, ranging from 6 cm before the Bragg peak (BP) to 3.5 cm beyond the BP in 5 mm steps with a 1 cm slit collimation (tungsten) showed a slight decrease of PG yields after the BP. Similar measurements with a semi-opened collimation configuration demonstrated a steeper decrease of PG yields after the BP. Keywords: cerium-bromide, prompt-gamma, time-of-flight, proton therapy, range verification, gamma-ray

spectra were acquired using HPGe-detector based gamma ray spectrometers at fixed shaping times of the amplifier and positions of the reference nuclides. The MCA dead times of the spectrometers were varied to incur the count rate losses to the peaks of in- terest. Three procedures were adopted to determine the dead time and random summing correction factors. The corrections to count rate data measured at LAB-A, which represented a maximum of 46% losses, were obtained within standard deviation figures of 2.9%, 1.3% and 0.4% and in LAB-B case the losses of 41%, were

the use of artificial fallout radionuclides (e.g., 137 Cs and 241 Am) from the atmospheric testing of nuclear weapons and/or the Chernobyl accident as independent chronostratigraphic markers ( O’Reilly et al ., 2011 ). The aim of the present study was, firstly, to compare two nuclear analytical techniques for 210 Pb analysis in sediment samples using LSC and gamma-ray spectrometer with well type HPGE detector and, secondly, to perform 210 Pb dating of sediment cores attributed to two lakes located in the Baltic Uplands. 2 Materials and methods The study was

intercomparison purpose) were performed using an HPGe gamma-ray spectrometer ORTEC-AMETEK model GEM 25 (34% relative efficiency and 1.65 keV FWHM for 60 Co at 1.33 MeV, 8192 channels) shielded with 10 cm lead internally lined with 2 mm copper foil [ 6 ]. Analyzed samples were counted for 60 ks. The water samples were measured in 0.5 L Marinelli beakers, while soil, sediment and biota samples were measured in polyethylene cylindrical containers. The HPGe detector calibration (energy and efficiency) was performed using mixed calibration source (MBSS 2 type from the Czech

Abstract

The new space project of M. V. Lomonosov Moscow State University on elaboration of multiple satellites for real time monitoring in the near-Earth space of radiation environment, natural (asteroids, meteoroids) and artificial (space debris) potentially dangerous objects, electromagnetic transients, such as cosmic gamma ray bursts, terrestrial gamma ray flashes, optical and ultraviolet bursts in the Earth atmosphere is presented. It is intended to install on the satellites the following instruments for space monitoring of dangerous objects and hazards: spectrometers of electrons and protons, complex of instruments for study of transient electromagnetic phenomena including gamma ray spectrometer, detectors of ultraviolet and optical emission and wide-field optical cameras. Successful implementation of the project for the first time in the world allows realization of a space system prototype for monitoring and preventing of space hazards for both ongoing and planned space missions, and also for aircraft flying in the upper atmosphere. There are also discussed results of experiments on-board Lomonosov in view of good experience of wide field camera use for monitor observations in space. These results formed the base of scientific program for the new project Universat- SOCRAT.

Abstract

The results of the specific activities of 232Th, 226Ra and 40K measured in samples of commonly used building materials in Bosnia and Herzegovina are presented. Measurements were performed by gamma-ray spectrometer with coaxial HPGe detector. The surface radon exhalation and mass exhalation rates for selected building materials were also measured. The determined values of specific activities were in range from 3.16±0.81 Bq kg−1 to 64.79±6.16 Bq kg−1 for 232Th, from 2.46±0.95 Bq kg−1 to 53.89 ±3.67 Bq kg−1 for 226Ra and from 28.44±7.28 Bq kg−1 to 557.30±93.38 Bq kg−1 for 40K. The radium equivalent activity, the activity concentration index, the external and internal hazard indices as well as the absorbed dose rate in indoor air and the corresponding annual effective dose, due to gamma-ray emission from the radioactive nuclides in the building material, were evaluated in order to assess the radiation hazards for people. The measured specific activities of the natural radioactive nuclides in all investigated building materials were compared with the published results for building materials from other European countries. It can be noted that the results from this study are similar to the data for building materials from neighbouring countries and for building materials used in the EU Member States. The radiological hazard parameters of the building materials were all within the recommended limits for safety use.

comparative study of the radon-induced background in low-level gamma-ray spectrometers. Appl Radiat Isot 2012;70:324–31. doi: 10.1016/j.apradiso.2011.09.023 13. Bučar K, Korun M, Vodenik B. Influence of the thorium decay series on the background of high-resolution gamma-ray spectrometers. Appl Radiat Isot 2012;70:1005–9. doi: 10.1016/j.apradiso.2012.03.014 14. Korun M, Maver Modec P, Vodenik B, Zorko B. Uranium-induced background of germanium gamma-ray spectrometers. Appl Radiat Isot 2012;70:1480–4. doi: 10.1016/j.apradiso.2012.05.001 15. Canberra Industries. Model 48

show degradation of resolution under radiation expo- sure, but solid state detectors do. Hence for longer flights solid-state detector radiation damage needs to be repeat- edly annealed in flight. Cooling of solid-state detectors can be active through mechanical coolers, which caused in the past some technical, but mostly energy use issues. Passive space based cooling places constraints on orbit and point- ing accuracy of solid-state detector passive coolers into dark space [5]. Gamma ray spectrometers on landers, on spacecraft in fly-by mode or highly elliptical