14 documents found, page 1 of 2
Ionization and scintillation of nuclear recoils in gaseous xenon
Renner, J.; Gehman, V. M.; Goldschmidt, A.; Matis, H. S.; Miller, T.; Nakajima, Y.; Nygren, D.; Oliveira, C. A. B.; Shuman, D.; Álvarez, V.
Radiopurity control in the NEXT-100 double beta decay experiment: procedures an...
Álvarez, V; Bandac, I.; Bettini, A.; Borges, F. I. G. M.; Cárcel, S.; Castel, J.; Cebrián, S.; Cervera, A.; Conde, C. A. N.; Dafni, T.
Photopeak shift effects due to the drift electric field in high pressure xenon ...
Neves, P. N. B.; Barata, J. A. S.; Távora, L. M. N.; Dias, T. H. V. T.; Borges, F. I. G. M.; Conde, C. A. N.The photopeak shift in High Pressure Xe (HPXe) gamma ray detectors due to the energy acquired/lost by the photoelectric and Compton electrons, from the electric field applied in the drift region, is calculated using the PENELOPE code for gamma rays from several radioactive sources. The implications of this effect in HPXe detectors are discussed, namely for TPCs for double beta decay of 136 Xe studies.
Experimental measurement of the mobilities of atomic, Ne+, and dimer, Ne2+, ion...
Garcia, A. N. C.; Trindade, A. M. F.; Oliveira, T. D. P.; Neves, P. N. B.; Barata, J. A. S.; Távora, L. M. N.; Dias, T. H. V. T.; Borges, F. I. G. M.We measured the reduced mobilities of the atomic, Ne+, and dimer, Ne2+, ions in Ne, under different pressures and reduced electric fields, at 300 K. The value obtained for the atomic ion, 4.1 cm2V1 s1, is in good agreement with other values published in the scientific literature. The value obtained for the mobility of the dimer ion, 7.3 cm2 V1 s1, is not in accordance with other published data. We discuss the m...
A Monte Carlo study of the electron clouds produced by polarized x-rays in xenon
Botte, G. S.; Rachinhas, P. J. B. M.; Dias, T. H. V. T.; Santos, F. P.; Távora, L. M. N.; Silva, R. M. Curado da; Conde, C. A. N.; Stauffer, A. D.Information about the polarization of x-ray photons can be determined by probing the direction of emission of photoelectrons and the profile of the electron cloud produced in the detecting medium. In this work we present Monte Carlo results for the electron clouds produced in xenon by the absorption of x-rays, considering a simple non-relativistic dipole approach to the angular differential photoionization cros...
Measurement of the photoelectron-collection efficiency in noble gases and methane
Coelho, L. C. C.; Ferreira, H. M. N. B. L.; Lopes, J. A. M.; Dias, T. H. V. T.; Ferreira, L. F. R.; Santos, J. M. F. dos; Breskin, A.; Chechik, R.The photoelectron-collection efficiency from photocathodes in noble gases and methane is experimentally investigated. The ratio between the number of transmitted photoelectrons in the gas media and in vacuum is determined as a function of the applied reduced electric field E/p, where p is the gas pressure. Results are presented for He, Ne, Ar, Xe, Kr and CH4.; http://www.sciencedirect.com/science/article/B6TJM-...
A simulation study of the effect of drift electric fields on the response of ra...
Távora, L. M. N.; Dias, T. H. V. T.; Conde, C. A. N.The effect of the presence of a drift electric field on the response of gaseous and semiconductor radiation detectors to energetic X-rays (energies from 20 to 200 keV) is investigated using the PENELOPE code to simulate the photo-absorption and the slow-down of the electrons produced in Si, Ge, and Xe gas at 1 atm. For typical drift fields, the energy deposited in the detection media is calculated taking into a...
Intrinsic limitations in the energy resolution of drift-field based radiation d...
Távora, L. M. N.; Conde, C. A. N.; Santos, F. P.; Dias, T. H. V. T.; Rachinhas, P. J. B. M.http://www.sciencedirect.com/science/article/B6TVT-4CJV8FD-4/1/9b1ae9691329367fa8f13902d8fd318d
A gas proportional-scintillation counter for x-ray spectrometry in the 0.1-3 ke...
Borges, F. I. G. M.; Santos, J. M. F. dos; Dias, T. H. V. T.; Santos, F. P.; Conde, C. A. N.Results for the energy resolution of a uniform-field gas proportional-scintillation counter are presented for the range 0.1-3 keV. A comparison with results from the literature shows that the detector is most suitable for this energy range. Examples of x-ray fluorescence pulse-height distributions from geological and industrial samples are presented. Copyright © 2004 John Wiley & Sons, Ltd.
Development of portable gas proportional scintillation counters for x-ray spect...
Santos, J. M. F. dos; Lopes, J. A. M.; Veloso, J. F. C. A.; Simões, P. C. P. S.; Dias, T. H. V. T.; Santos, F. P.; Rachinhas, P. J. B. M.A review on gas proportional scintillation counters (GPSCs) is presented. Recent achievements towards the portability of simple, inexpensive and compact GPSCs are discussed. Compensation of solid angle effects with the curved grid technique can be used to produce non-focused GPSCs with medium-sized radiation windows, at least up to 80% of the photosensor active diameter, without degradation of detector performa...