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Sample records for fission track detectors

  1. Measurement of fission track of uranium particle by solid state nuclear track detector

    International Nuclear Information System (INIS)

    Son, S. C.; Pyo, H. W.; Ji, K. Y.; Kim, W. H.

    2002-01-01

    In this study, we discussed results of the measurement of fission tracks for the uranium containing particles by solid state nuclear track detector. Uranium containing silica and uranium oxide particles were prepared by uranium sorption onto silica powder in weak acidic medium and laser ablation on uranium pellet, respectively. Fission tracks for the uranium containing silica and uranium oxide particles were detected on Lexan plastic detector. It was found that the fission track size and shapes depend on the particle size uranium content in particles. Correlation of uranium particle diameter with fission track radius was also discussed

  2. Critical angles for fission fragment registrations in some solid state track detectors

    Energy Technology Data Exchange (ETDEWEB)

    Belyaev, A D; Bahromi, I I; Beresina, N V [AN Uzbekskoj SSR, Tashkent. Inst. Yadernoj Fiziki; and others

    1980-03-01

    In studies of the registration efficiency of various solid state track detectors (polycarbonate, polyethyleneterephthalate, cellulose nitrate and muscovite) the detectors were irradiated with spontaneous fission fragments from /sup 252/Cf and with fission fragments from /sup 235/U separated according to mass and energy. Experimental details are given. Critical angles for the registration of fission fragments in the various detectors are given for specified energies and masses.

  3. Characteristics of diallyl phthalate resin as a fission track detector

    CERN Document Server

    Tsuruta, T

    1999-01-01

    Diallyl phthalate (DAP) resin plates were irradiated with fission fragments, and then etched in aqueous solution of KOH. Etched tracks were observed and counted by using an optical microscope. The detection efficiency of fission fragments was about 100% for both perpendicular and random incidence. DAP plates were insensitive to alpha particles and fast neutrons. These characteristics are suitable for detecting selected fission fragments, which coexist with alpha particles or fast neutrons. DAP plates are valuable for quantitative analysis of fissionable materials and neutron dosimetry. DAP and allyl diglycol carbonate (CR-39) were formed into copolymers in various ratios. The copolymers showed intermediate characteristics between DAP and CR-39. The fabrication of the copolymers made it possible to control the discrimination level for detection of heavy charged particles.

  4. Fission distribution measurements of Atucha's fuel pellets with solid state track detectors

    International Nuclear Information System (INIS)

    Ricabarra, M.D. Bovisio de; Waisman, Dina.

    1979-08-01

    Distribution of fissions in a UO 2 rod has been measured by means of solid state detectors. Mica muscovite and Makrofol-N detectors were used in the experiment. The merits of mica muscovite relative to the Makrofol-N for the detection of fission fragments have been verified. However both fission track detectors closely agree (0,5%) in the final fission distribution of the UO 2 rod. Sensitivity of the detectors shows to be linear in the range between 50.000and 360.000 fission tracks per square centimeter. Due to the high spatial resolution this method is better than any other technique. Determination were made in UO 2 pellets similar to the fuel element of the Atucha reactor. The average fission rate in the rod has been measured within 0,8% error, and provides an accurate determination for the distribution of fissions in the rod wich is needed for the determination of energy liberated per fission in the natural uranium rod.(author) [es

  5. Studies of isothermal annealing of fission fragment and alpha particle tracks in Cr-39 polymer detectors

    International Nuclear Information System (INIS)

    Zaky, M.F.; Youssef, A.A.

    2002-01-01

    Two groups of CR-39 detectors samples are exposed to two types of charged particle radiation. The first group are severe damaged with fission fragment tracks from 2 52C f source. The second accepted alpha particles resulting from the interaction of highly energetic 1 9F -ions and a copper disk with thickness 1 cm, which are of less damage tracks than fission fragments. , The isothermal annealing of tracks in the temperature range from 175 to 300 degree C in step 25 degree C for annealing time of 10,15,20,25 and 30 minutes has been investigated. The changes introduced in the track density and track diameter for two types of irradiation in the detector have been observed and compared between them. The results indicate that the track density and the size of the tracks are considerably changed due to annealing

  6. Detection alpha particles and Cf-252 fission fragments with track solid detectors and with surface barrier detectors: efficiency determination

    International Nuclear Information System (INIS)

    Khouri, M.T.F.C.; Koskinas, M.F.; Andrade, C. de; Vilela, E.C.; Hinostroza, H.; Kaschiny, J.R.A.; Costa, M.S. da; Rizzo, P.; Santos, W.M.S.

    1990-01-01

    The technique of particle detection by solid track detectors, types of developing and analysis of results are presented. Efficiency measurements of alpha particle detection with Makrofol e and surface barrier detector are made. Detection of Cf-252 fission fragments is shown. (L.C.)

  7. Detection of alpha particles and Cf-252 fission fragments with solid track detectors and surface barrier detector. Efficiency calculation

    International Nuclear Information System (INIS)

    Khouri, M.T.F.C.; Koskinas, M.F.; Andrade, C. de; Vilela, E.C.; Hinostroza, H.; Kaschiny, J.E.A.; Costa, M.S. da; Rizzo, P.; Santos, W.M.S.

    1990-01-01

    A technique for particle detection by using track solid detector and also types of revealing and result analysis are presented concerned to Cf-252 fission fragments detection. Measurements of alpha particles detection efficiency using Makrofol E and surface barrier detector are performed. (L.C.J.A.)

  8. Detection of fission fragments using thick samples in contact with solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Lima, D.A. de; Martins, J.B.; Tavares, O.A.P.

    1987-01-01

    Whenever use is made of thick samples in contact with solid state nuclear track detectors for determining fission yields, one of the fundamental problems is the evaluation of the effective number of target nuclei which contributes to the fraction of the number of fission events that will be recorded. The evaluation of the effective number of target nuclei which contributes to recorded events is based on the effective thickness of the sample. A method for evaluating effective thickness of thick samples for binary fission modes, is presented. A cross section equation which takes into account all the necessary corrections due to fragment attenuation effects by a thick target for calculation induced fission yields, was obtained. (Author) [pt

  9. Application of fission track detectors to californium-252 neutron dosimetry in tissue near the radiation source

    International Nuclear Information System (INIS)

    Oswald, R.A.; Lanzl, L.H.; Rozenfeld, M.

    1981-01-01

    Fission track detectors were applied to a unique problem in neutron dosimetry. Measurements of neutron doses were required at locations within a tumor of 1 cm diameter implanted on the back of a mouse and surrounded by a square array of four 252 Cf medical sources. Measurements made in a tissue-equivalent mouse phantom showed that the neutron dose rate to the center of the tumor was 2.18 rads mg -1 h -1 +- 8.4%. The spatial variation of neutron dose to the tumor ranged from 1.88 to 2.55 rads mg -1 h -1 . These measurements agree with calculated values of neutron dose to those locations in the phantom. Fission track detectors have been found to be a reliable tool for neutron dosimetry for geometries in which one wishes to know neutron dose values which may vary considerably over distances of 1 cm or less

  10. Application of fission track detectors to californium-252 neutron dosimetry in tissue near the radiation source

    International Nuclear Information System (INIS)

    Oswald, R.A.; Lanzl, L.H.; Rozenfeld, M.

    1981-01-01

    Fission track detectors were applied to a unique problem in neutron dosimetry. Measurements of neutron doses were required at locations within a tumor of 1 cm diameter implanted on the back of a mouse and surrounded by a square array of four 252 Cf medical sources. Measurements made in a tissue-equivalent mouse phantom showed that the neutron dose rate to the center of the tumor was 2.18 rads micrograms-1 h-1 +/- 8.4%. The spatial variation of neutron dose to the tumor ranged from 1.88 to 2.55 rads micrograms-1 h-1. These measurements agree with calculated values of neutron dose to those locations in the phantom. Fission track detectors have been found to be a reliable tool for neutron dosimetry for geometries in which one wishes to know neutron dose values which may vary considerably over distances of 1 cm or less

  11. Mica fission detectors

    International Nuclear Information System (INIS)

    Wong, C.; Anderson, J.D.; Hansen, L.; Lehn, A.V.; Williamson, M.A.

    1977-01-01

    The present development status of the mica fission detectors is summarized. It is concluded that the techniques have been refined and developed to a state such that the mica fission counters are a reliable and reproducible detector for fission events

  12. Solid state nuclear track detectors in the measurement of alpha to fission branching ratios of heavy actinides

    International Nuclear Information System (INIS)

    Pandey, A.K.; Sharma, R.C.; Padalkar, S.K.; Kalsi, P.C.; Iyer, R.H.

    1992-01-01

    A sequential etching procedure for revelation of alpha and fission tracks in CR-39 was developed and optimized. Using this technique alpha and fission tracks can be differentiated unambiguously because of significant differences in their sizes and etching times. This registration and revelation procedure for alpha and fission tracks may be used for the studies of half lives, alpha to fission branching ratios and identification of radionuclides based on their decay schemes. It has the added advantage that both alpha decay and fission events can be studied using one detector and hence uncertainties related to efficiency, registration geometry, registration times, amount of radionuclides etc can be eliminated or minimized. The effects of neutron, gamma and alpha radiations on the alpha and fission fragment tracks registration and revelation properties of CR-39 detectors [CR-39, CR-39 (DOP)] were also studied. The IR spectra were also studied to find out the nature of chemical changes produced by these radiations on CR-39. (author). 32 refs., 7 figs., 4 tabs

  13. Enlarging the fission fragment tracks in glass detectors by etching in weak solutions of HF - a safe etchant

    International Nuclear Information System (INIS)

    Singh, V.P.; Sharma, A.P.

    1982-01-01

    The effect of etchant concentration and temperature on track revelation properties of soda glass detectors has been studied. Etch rate ratio, maximum observable diameter and the energy resolution of the fission fragment tracks of 252 Cf in glasses are increased when the samples are etched in 1.25 vol% HF as compared to higher concentrations of HF and other etching solutions. The critical angle of etching is found to decrease with decrease in etchant concentration. The activation energies for bulk etching and track etching have also been estimated. Better results were obtained by using lower etching temperatures. (author)

  14. A method for the measurement of fission rates in fast neutron fields using solid state track detectors

    International Nuclear Information System (INIS)

    Hansen, W.; Vogel, W.

    1984-04-01

    Solid state track detectors (SSTDs) are increasingly used for the registration of radiation in different fields of nuclear physics. Because of their small sizes and masses and the absence of any electronics during exposure SSTDs do not cause distortions in the system to be investigated and are useful for measurements at such places being difficult of access. The elaboration of a method is described for fission rate measurements in fast neutron fields applying SSTDs and different fissionable isotopes which were electrodeposited on stainless steel backings. Experiences of the electrodeposition and results of quality checks are presented. The evaluation of the etched tracks is performed with spark counter technique. The dependence of the counting result on essential influence parameters is discussed. (author)

  15. Measurement of the energy spectrum of {sup 252}Cf fission fragments using nuclear track detectors and digital image processing

    Energy Technology Data Exchange (ETDEWEB)

    Espinosa, G.; Golzarri, J. I. [UNAM, Instituto de Fisica, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Castano, V. M. [UNAM, Centro de Fisica Aplicada y Tecnologia Avanzada, Boulevard Juriquilla 3001, Santiago de Queretaro, 76230 Queretaro (Mexico); Gaso, I. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Mena, M.; Segovia, N. [UNAM, Instituto de Geofisica, Circuito de la Investigacion Cientifica, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)

    2010-02-15

    The energy spectrum of {sup 252}Cf fission fragments was measured using nuclear track detectors and digital image analysis system. The detection material was fused silica glass. The detectors were chemically etched in an 8% HF solution. After experimenting with various etching time, it was found that the best resolution of the track diameter distribution was obtained after 30 minutes of etching. Both Gaussian and Lorentzian curves were fit to the track diameter distribution histograms and used to determine the basic parameters of the distribution of the light (N{sub L}) and heavy (N{sub H}) formed peaks and the minimum of the central valley (N{sub V}). Advantages of the method presented here include the fully-automated analysis process, the low cost of the nuclear track detectors and the simplicity of the nuclear track method. The distribution resolution obtained by this method is comparable with the resolution obtained by electronic analysis devices. The descriptive variables calculated were very close to those obtained by other methods based on the use of semiconductor detectors. (Author)

  16. Natural uranium impurities in fission track detectors and associated geocronological parameters

    International Nuclear Information System (INIS)

    Ricabarra, G.H.; Bovisio de Ricabarra, M.D.; Waisman, Dina; Faradjie de Turjanski, Rosa

    1981-01-01

    A technique, based in counting neutron induced fission tracks, has been developed for the measurement of uranium impurities in mica. Uranium concentrations of 10 -10 and 10 -9 (U atom/mica atom) have been measured. As a part of the development of this technique, the mica geological age was also measured, by fossil and induced track detection. The agreement obtained by this method, T = (472+-52) x 10 6 years with that of (450+-15) x 10 6 years obtained by the Ar-K technique is satisfactory and is an indirect test of the fission track technique used. A careful analysis of the neutron field parameters and nuclear data used in the age determination was made. This analysis is useful for applications in geocronology. According to this analysis a value of lambdasub(f)=(7.1+-0.1) x 10 -17 years -1 is recommended for the spontaneous fission of U238. However, in order to compare the results, the quoted age, T=(472+-52) x 10 6 years, was obtained with the generally accepted value of lambdasub(f)=(6.85-0.20) x 10 -17 years -1 (Fleischer and Price 1964). (author) [es

  17. Response study of fission track detectors using two different moderator designs in a high-energy radiation field

    International Nuclear Information System (INIS)

    Mayer, S.; Boschung, M.; Fiechtner, A.; Fuerstner, M.; Wernli, C.

    2008-01-01

    Fission track detectors in the center of moderating spheres are routinely used to measure the ambient dose equivalent due to neutrons in the environmental dosimetry at Paul Scherrer Institut (PSI). Originally, the system was designed to cope with neutrons from skyshine effects. Later, the system was also adapted behind the shielding of PSI's accelerators. Nowadays, as a consequence of continuously upgrading accelerator energies and intensities, the neutron energy behind thick shielding can range from fractions of eV to about 1 GeV (e.g. at CERN). For this reason a measurement campaign in a high-energy stray radiation field at CERN's High-Energy Reference Field Facility (CERF) was initiated to study and compare the response of the already existing detector-moderator configuration and a new design, the 'GSI ball'. Employing an additional lead layer in a moderator sphere of 32.5 cm diameter, the GSI ball was primarily designed for the use with thermoluminescent based dosimeters in its center in order to optimize the response for the measurement of H*(10) to higher neutron energies. In this work, the measurement results for fission track detectors using two different radiator materials in the PSI and the GSI moderator are presented. Based on these studies, on the one hand, field calibration factors for the use in presumably similar high-energy fields around accelerators could be deduced. On the other hand, it could be shown that there is no need to replace the established PSI moderator by the GSI moderator since the combination of fission track detector and GSI moderator does not result in a significant sensitivity improvement

  18. Response study of fission track detectors using two different moderator designs in a high-energy radiation field

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, S. [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)], E-mail: Sabine.Mayer@psi.ch; Boschung, M.; Fiechtner, A. [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Fuerstner, M. [CERN, CH-1211 Geneva 23 (Switzerland); Wernli, C. [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

    2008-02-15

    Fission track detectors in the center of moderating spheres are routinely used to measure the ambient dose equivalent due to neutrons in the environmental dosimetry at Paul Scherrer Institut (PSI). Originally, the system was designed to cope with neutrons from skyshine effects. Later, the system was also adapted behind the shielding of PSI's accelerators. Nowadays, as a consequence of continuously upgrading accelerator energies and intensities, the neutron energy behind thick shielding can range from fractions of eV to about 1 GeV (e.g. at CERN). For this reason a measurement campaign in a high-energy stray radiation field at CERN's High-Energy Reference Field Facility (CERF) was initiated to study and compare the response of the already existing detector-moderator configuration and a new design, the 'GSI ball'. Employing an additional lead layer in a moderator sphere of 32.5 cm diameter, the GSI ball was primarily designed for the use with thermoluminescent based dosimeters in its center in order to optimize the response for the measurement of H*(10) to higher neutron energies. In this work, the measurement results for fission track detectors using two different radiator materials in the PSI and the GSI moderator are presented. Based on these studies, on the one hand, field calibration factors for the use in presumably similar high-energy fields around accelerators could be deduced. On the other hand, it could be shown that there is no need to replace the established PSI moderator by the GSI moderator since the combination of fission track detector and GSI moderator does not result in a significant sensitivity improvement.

  19. $\\bar{p}$-Induced Fission Studies with Plastic Track Detectors Using 4$\\pi$-Geometry

    CERN Multimedia

    2002-01-01

    % EMU20 \\\\ \\\\ The annihilation of a stopped antiproton on the surface of a target nucleus produces on the average five pions with a mean energy of 230~MeV. The high excitation of the nuclei with low angular momentum transfer can also be achieved by direct pion-nucleus interactions. The fission probabilities of highly excited nuclei can be explained on the basis of high energy limit of statistical theory. Previously the binary fission and higher multiplicity break-up of various nuclei caused by the absorption of pions has been studied by our group. The mechanism of nuclear excitation may still be the same when an antiproton annihilates in a nucleus and produces pions. It would be interesting to see whether the $\\bar{p}$ annihilation produces high enough excitation energies for nuclear phase-transition to take place. If so, then the fragmentation would overwhelm binary and ternary fission process. \\\\ \\\\The use of a highly sensitive plastic detector, CR-39, was made by our group in a number of studies involving ...

  20. Solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Medeiros, J.A.; Carvalho, M.L.C.P. de

    1992-12-01

    Solid state nuclear track detectors (SSNTD) are dielectric materials, crystalline or vitreous, which registers tracks of charged nuclear particles, like alpha particles or fission fragments. Chemical etching of the detectors origin tracks that are visible at the optical microscope: track etching rate is higher along the latent track, where damage due to the charged particle increase the chemical potential, and etching rate giving rise to holes, the etched tracks. Fundamental principles are presented as well as some ideas of main applications. (author)

  1. The fission track method

    International Nuclear Information System (INIS)

    Hansen, K.

    1990-01-01

    During the last decade fission track (FT) analysis has evolved as an important tool in exploration for hydrocarbon resources. Most important is this method's ability to yield information about temperatures at different times (history), and thus relate oil generation and time independently of other maturity parameters. The purpose of this paper is to introduce the basics of the method and give an example from the author's studies. (AB) (14 refs.)

  2. Sequential fission process observed in the reaction (16.7 MeV/u) 238U + nat.Au using mica as dielectric track detector

    International Nuclear Information System (INIS)

    Shahzad, Muhammad Ikram; Qureshi, Imtinan Elahi; Manzoor, Shahid; Khan, Hameed Ahmed

    1999-01-01

    The evidence of sequential fission has been found in the heavy-ion reaction (16.7 MeV/u) 238 U + nat. Au, using muscovite mica as Dielectric Track Detector (DTD) placed in a 2π-geometry configuration. The reaction products originating from the interactions of 238 U ions with the atoms of gold were registered in the detector in the form of tracks and identified for performing a detailed kinematical analysis. For this purpose the spherical polar coordinates of the correlated tracks of the multipronged events have been analyzed on an event-by-event basis. Automatic, semi-automatic and manual measuring methods have been employed to collect and manipulate the track data. The known characteristics of binary and ternary events observed in the reaction have been used for the calibration of the detectors. The computed masses, Q-values and relative velocities of the reaction products determined in this analysis are compared with theoretical predictions based on sequential fission process. Agreement within one standard deviation with respect to the experimental values has been found for the majority of analyzed events. Therefore, it is concluded that three particles in the exit channel of the reaction are produced in two successive steps. In the first step of the reaction, two intermediate nuclei are formed as a result of an inelastic collision between projectile and target atoms while in the second step the fission of one of the intermediate nuclei of the previous step takes place. Furthermore no proximity effects have been observed

  3. Calibration of a special neutron dosemeter based on solid-state track detectors and fission radiators in various neutron fields

    International Nuclear Information System (INIS)

    Doerschel, B.; Krusche, M.; Schuricht, V.

    1980-01-01

    The calibration of a personnel neutron dosemeter in different neutron fields is described. The badge-like dosemeter contains 5 detectors: polycarbonate foil (10 μm, Makrofol KG), 232 Th, natural uranium, natural uranium with boron, and natural uranium with cadmium. Detector sensitivity and calibration factors have been calculated and measured in radiation fields of 252 Cf fission neutrons, WWR-S reactor neutrons with and without Cd and Fe shielding, 3-MeV (d,t) generator neutrons, and 238 PuBe neutrons. Measurement range and achievable accuracy are discussed from the point of view of applying the dosemeter in routine and emergency uses

  4. Sequential fission process observed in the reaction (16.7 MeV/u) {sup 238}U + {sup nat.}Au using mica as dielectric track detector

    Energy Technology Data Exchange (ETDEWEB)

    Shahzad, Muhammad Ikram; Qureshi, Imtinan Elahi; Manzoor, Shahid; Khan, Hameed Ahmed

    1999-01-04

    The evidence of sequential fission has been found in the heavy-ion reaction (16.7 MeV/u) {sup 238}U + {sup nat.}Au, using muscovite mica as Dielectric Track Detector (DTD) placed in a 2{pi}-geometry configuration. The reaction products originating from the interactions of {sup 238}U ions with the atoms of gold were registered in the detector in the form of tracks and identified for performing a detailed kinematical analysis. For this purpose the spherical polar coordinates of the correlated tracks of the multipronged events have been analyzed on an event-by-event basis. Automatic, semi-automatic and manual measuring methods have been employed to collect and manipulate the track data. The known characteristics of binary and ternary events observed in the reaction have been used for the calibration of the detectors. The computed masses, Q-values and relative velocities of the reaction products determined in this analysis are compared with theoretical predictions based on sequential fission process. Agreement within one standard deviation with respect to the experimental values has been found for the majority of analyzed events. Therefore, it is concluded that three particles in the exit channel of the reaction are produced in two successive steps. In the first step of the reaction, two intermediate nuclei are formed as a result of an inelastic collision between projectile and target atoms while in the second step the fission of one of the intermediate nuclei of the previous step takes place. Furthermore no proximity effects have been observed.

  5. Forward tracking detectors

    Indian Academy of Sciences (India)

    Abstract. Forward tracking is an essential part of a detector at the international linear collider (ILC). The requirements for forward tracking are explained and the proposed solutions in the detector concepts are shown.

  6. Alkaline glass as induced fission fragment detectors

    International Nuclear Information System (INIS)

    Amorim, A.M.M.

    1986-01-01

    The slide glass, registered trade marks INLAB, INVICT and PERFECTA were compared. For the three kinds of glasses the following studies were done: chemical composition; general dissolution rate for hydrofluoric acid solutions of concentrations between 1 and 10M, at 30 0 C and ultrasound shaking; relative efficiency for recording fission fragment tracks from 252 Cf. The INLAB glass was selected due to the better quality of its surface after chemical etching. The HF concentration 2.5M was determined for chemical etching of INLAB glass, and the optimum etching time was chosen between 8 and 10 minutes. The thermal attenuation of latent tracks in the environmental temperature was observed for intervals uo to 31 days between the detector exposure to the fission fragment source and etching of tracks. Several methods were used for determining the detector parameters, such as: critical angle, angle of the cone and efficiency of etching. The effects of gamma irradiation from 60 Co and reactor neutrons in material properties as track detector were studied. Attenuation of latent tracks and saturation of color centers were observed for doses over 100M Rad. Since this kind of material contains uranium as impurity, uniformely distributed, slide glass were calibrated to be applied as a monitor of thermal neutron flux in nuclear reactor. (Author) [pt

  7. Fission tracks dating for obsidian

    International Nuclear Information System (INIS)

    Picon, C.

    1991-01-01

    Obsidian from South America are dated by fission tracks methods. Samples are irradiated in a nuclear reactor with a flux of 10 15 n/cm 2 . Results, corrected by 'Plateau' methods, are the following: obsidian from Bolivia: 4.14 x 10 6 yr., Ecuador: 8.79 x 10 5 yr., Colombia: 3.52 x 10 6 yr., Peru: 6.55 x 10 6 yr., Chile: 1.13 x 10 6 yr. (MMZ). 5 refs., 3 tabs

  8. Fission tracks diameters in glasses

    International Nuclear Information System (INIS)

    Garzon Ruiperez, L.; Veiguela, J.

    1974-01-01

    Standard glass microscope slides have been irradiated with fission fragments from the uranium. The etching track conditions have been the same for the series, having changed the etching time only for each specimen. For each glass, a minimum of 250 measurements of the tracks diameters have been made, the distributions of which are the bimodal type. Diameters-etching dependence with time is roughly lineal. Energy determinations have been made with the help of the diameters-energy relations. The calculated values agree very well with the know ones. (author) [es

  9. Fission - track age of the Marjalahti Pallasite

    International Nuclear Information System (INIS)

    Bondar, Yu.V.; Perelygin, V.P.

    2006-01-01

    Full text: Investigation of fossil charged-particle tracks in various mineral phases of extraterrestrial samples is a powerful method for research the early stages of the solar system. Over geological time, meteorites crystals have accumulated a record of tracks produced by heavily charged energetic particles from both internal (spontaneous fission of 238U and some other extinct isotopes) and external sources (galactic cosmic rays with Z>20). The fortunate fact that meteorite grains can accumulate latent and very long-lived tracks since soon after the end of nucleosynthesis in the solar nebula enables one to decode their radiation history and to detect any thermal events in the meteorite cosmic history by revealing these tracks through suitable etching procedures. Only a few minerals in meteorites (mainly phosphates) contain small amount of uranium; the fact that 238 U undergoes fission with fission-decay constant λ f ∼ 8.2x10 -17 yr -1 allows one to use this isotope as a chronometer. By measuring the U concentration in the crystals (by reactor irradiation) and the density of the spontaneous-fission tracks it is relatively easy to calculate the 'fission-track age' if 238 U is the main source of fission tracks. However the fission-track dating of extraterrestrial samples compared with the terrestrial ones has some peculiar features due to presence of a number of other potential track sources except the spontaneous fission of 238 U, such as the spontaneous fission of presently extinct 244 Pu, heavy nuclei of cosmic rays and induced fission by cosmic ray primaries. Only tracks from the spontaneous fission of U and Pu are suitable for fission-track dating. The competing effects of these fissioning elements, whose half-lives differ by a factor of ∼50, form a basis for a fission-track chronology for samples older than ∼ 4.0 Gyr. Over small intervals in time (∼ few x10 8 yr ) the track density from spontaneous fission of 238 U is nearly constant. However, the

  10. Solid state track detectors

    International Nuclear Information System (INIS)

    Reuther, H.

    1976-11-01

    This paper gives a survey of the present state of the development and the application of solid state track detectors. The fundamentals of the physical and chemical processes of the track formation and development are explained, the different detector materials and their registration characteristics are mentioned, the possibilities of the experimental practice and the most variable applications are discussed. (author)

  11. Fission track geochronology of Eastern Ghats

    Energy Technology Data Exchange (ETDEWEB)

    Virk, H S; Koul, S L; Singh, S [Punjabi Univ., Patiala (India). Dept. of Physics

    1978-12-01

    Fission track geochronology of Eastern Ghats has been established by using fission track technique in dating micaceous and accessory minerals occurring in the region. Annealing studies confirm that radiation damage fossil tracks can be erased in minerals under intense metamorphic episodes thus resetting the geological clock. The fission track ages of the minerals range between 450 +- 5 m.y. to 622 +- 148 m.y. It is concluded that f.t. ages of the minerals date the last metamorphic event of the Eastern Ghats, known as the Indian Ocean Cycle.

  12. Fission track dating of zircon: a multichronometer

    International Nuclear Information System (INIS)

    Carpena, J.

    1992-01-01

    Scattering in Fission Track ages of zircons of a single rock is possible when they present morphological and geochemical variations, if the greatest care is not taken in the choice of the etching conditions and the counting of tracks. The Fission Track study of two heterogeneous populations of zircons from the Mont Blanc granite and from the Gran Paradiso gneisses allows to show that zircon may work as a multichronometer

  13. An improved technique for fission track dating

    International Nuclear Information System (INIS)

    Zhao Yunlong; Wu Zhaohui; Xia Yuliang

    1996-01-01

    The necessity of improving the fission track dating (FTD) technique both at home and abroad is illustrated. The ways of making such improvement are also proposed. It is suggested to calibrate the constant b value of the uranium standard glass by using the method of fission products activity. The 3 kinds of uranium standard glass which have been calibrated are NBS SRM962a, UB 1 and UB 2 . An established new method σ·Φ ρ d /b, to measure neutron fluence, avoids the influence of the varying neutron spectrum on measuring neutron fluence. The improved etching technique for fission tracks in zircon adopted a two-step method which includes the molten alkali system etching using NaOH + KOH and the mixed acid system etching using HNO 3 + HF; this technique results in adequate track etching, increased track clarity and less interference. In this way the intensity of tracks is authentically reflected. Dividing angular zone in accordance with the angular distribution of spontaneous fission track on the crystal surface of minerals to count the tracks and using the improved etching technique to remove the non-uniform angular distribution of spontaneous fission tracks in zircon, ensure the accuracy of tracks count. The improved FTD techniques were used to finish Laboratory Standardized Calibration. The tests using international FTD age standards samples have proved that above mentioned techniques are reliable and practical in obtaining the accurate FTD data. (8 tabs.; 3 figs.)

  14. Fission track method for uranium ore exploration

    International Nuclear Information System (INIS)

    Guo Shilun; Deng Xinlu; Sun Shengfen; Meng Wu; Zhang Pengfa; Hao Xiuhong

    1986-01-01

    The uranium concentrations in natural water collected in the fields of uranium ore exploration with fission track method have been determined. It shows that the results of fission track method are consistent with that of fluoro-colorimetry and laser fluorometry for the same samples of water with uranium concentration in the region of 10 -4 to 10 -8 g/l. For water samples with lower uranium concentration (≤10 -8 g/l), the fission track method can still give accurate or referential results, but the other two methods failed. The reproducibility of fission track method was checked and discussed by using samples collected in the same fields of uranium ore exploration. The effects of the concentration of the impurities in natural water on determination of uranium concentration were analysed and discussed as well

  15. Device for glass detector tracks processing

    International Nuclear Information System (INIS)

    Zhukov, A.V.; Mikheev, V.P.; Pis'mennyj, G.V.; Pribytov, V.I.; Rozov, B.S.

    1974-01-01

    The authors describe a semi-automatic installation for measuring angular distribution of tracks from nuclear fission fragments. The measurements were performed on glass detectors represented by a cylinder surface section with central angle 110-120 deg, height 20 mm and radius 45 mm. The tracks were in the form of lunes, 10/25 mm deep. Treatment of one detector lasted 10-15 min. The installation affords the possibility of finding the angular distribution of tracks by counting them in zones, whose sizes may vary from 1 to 90 deg. Data output was performed on a digitizer [ru

  16. Muon induced fission and fission track dating of minerals

    International Nuclear Information System (INIS)

    Marques, A.

    1988-01-01

    The effects of muon induced fission on geological dating of samples by the fission track method are evaluated for the case of muscovite minerals. It is found a small but significant effect, greater for the longer ages. Since calculations are developped under the hypothesis of constant atmosphere and primary cosmic ray flux it is suggested that any discrepancy found in ages of very old material that cannot be accounted for by well known environmental influences, be taken as an indication of variation on either the atmospheric stopping power or the intensity of cosmic radiation along the ages. (author) [pt

  17. Latent tracks in polymeric etched track detectors

    International Nuclear Information System (INIS)

    Yamauchi, Tomoya

    2013-01-01

    Track registration properties in polymeric track detectors, including Poly(allyl diglycol carbonate), Bispenol A polycarbonate, Poly(ethylen terephtarate), and Polyimide, have been investigated by means of Fourie transform Infararede FT-IR spectrometry. Chemical criterion on the track formation threshold has been proposes, in stead of the conventional physical track registration models. (author)

  18. Fission track dating of kimberlitic zircons

    International Nuclear Information System (INIS)

    Haggerty, S.E.

    1983-01-01

    The only reliable method for dating kimberlites at present is the lengthy and specialized hydrothermal procedure that extracts 206 Pb and 238 U from low-uranium zircons. This paper describes a second successful method by fission track dating of large single-crystal zircons, 1.0-1.5 cm in dimension. The use of large crystals overcomes the limitations imposed in conventional fission track analysis which utilizes crushed fragments. Low track densities, optical track dispersion, and the random orientation of polished surfaces in the etch and irradiation cycle are effectively overcome. Fission track ages of zircons from five African kimberlites are reported, from the Kimberley Pool (90.0 +- 6.5 m.y.), Orapa (87.4 +- 5.7 and 92.4 +- 6.1 m.y.), Nzega (51.1 +- 3.8 m.y.), Koffiefontein (90.9 +- 8.2 m.y.), and Val do Queve (133.4 +- 11.5 m.y.). In addition we report the first radiometric ages (707.9 +- 59.6 and 705.5 +- 61.0 m.y.) of crustal zircons from kimberlites in northwest Liberia. The fission track ages agree well with earlier age estimates. Most of the zircons examined in this study are zoned with respect to uranium but linear correlations are established (by regression analysis) between zones of variable uranium content, and within zones of constant uranium content (by analysis of variance). Concordance between the fission track method and the U/Pb technique is established and we concluded that track fading from thermal annealing has not taken place. Kimberlitic zircons dated in this study, therefore, record the time of eruption. (orig.)

  19. Obsidian dating by fission track method

    International Nuclear Information System (INIS)

    Araya, A.M.O.

    1990-12-01

    The fission track method was employed to obtain the age of twelve obsidian sample from Ecuador. By using the plateau-age correction method, we obtained the true age of each sample and were able to identify four groups of ages in the studied area. Thereafter we studied the fading of fission tracks in two obsidian samples with different origins: Yanaurcu, Ecuador and Monte Arci, Italy. We constructed Arrhenius plots and calculated activation energies for both samples. The results from thermal annealing experiments were compared with theoretical curves obtained by integrating an equation proposed by Shukolyukov et al (1965). (author). 43 refs, 20 figs, 10 tabs

  20. Fission studies of gold induced by (1665 MeV) π- using a CR-39 detector

    International Nuclear Information System (INIS)

    Muhammad Ikram Shahzad; Yasin, Zafar; Sher, Gul

    2012-01-01

    The fission cross section and fission probability of 197 Au, induced by (1665 MeV) π'-, have been studied using CR-39 track detectors. A 4π-geometry was used to count track statistics. A beam of negative pions of 1665 MeV was produced at AGS of Brookhaven National Laboratory, USA, and allowed to fall normally on the stack. Two detectors from the stack were scanned for fission fragment tracks after etching in 6N NaOH at 70 ℃. The statistics of fission fragment tracks in both detectors were obtained. It was found that there was a marked asymmetry of registered tracks with respect to the forward and backward hemispheres. This asymmetry could be partly accounted for on the basis of momentum transfer to the struck nucleus. On the basis of counting statistics fission cross section was measured, and fission probability was determined by dividing the fission cross section with the reaction cross section. The fission cross-section and fission probability were compared with the computed values using the cascade-exciton model code CEM95. (authors)

  1. Diallyl phthalate (DAP) solid state nuclear track detector

    CERN Document Server

    Koguchi, Y; Ashida, T; Tsuruta, T

    2003-01-01

    Diallyl phthalate (DAP) solid state nuclear track detector is suitable for detecting heavy ions such as fission fragments, because it is insensitive to right ions such as alpha particles and protons. Detection efficiency of fission tracks is about 100%, which is unaffected under conditions below 240degC lasting for 1h or below 1 MGy of gamma-ray irradiation. Optimum etching condition for the DAP detector for detection of fission fragments is 2-4 h using 30% KOH aqueous solution at 90degC or 8-15 min using PEW-65 solution at 60degC. DAP detector is useful in detecting induced fission tracks for dating of geology or measuring intense heavy ions induced by ultra laser plasma. The fabrication of copolymers of DAP and CR-39 makes it possible to control the discrimination level for detection threshold of heavy ions. (author)

  2. A new look at statistics in fission-track dating

    International Nuclear Information System (INIS)

    Green, P.F.

    1981-01-01

    Poissonian errors, as routinely applied in fission-track dating, represent a limiting case, which may not always be attainable in practice. Other experimental factors may introduce additional non-Poissonian errors, which must be taken into account. In the population method, sampling of non-homogeneous uranium distributions introduces experimental error. In the external detector method (EDM), many factors exist to introduce such error. Simply quoting total numbers of spontaneous and induced fission tracks obtained by the EDM may disguise the possible influence of experimental variation. The present work concentrates on the EDM, and describes a test which has recently been proposed to detect the presence of experimental error in EDM analyses. The question of an alternative analysis for cases where such error is present is also considered. A method of presenting EDM data is suggested, which allows assessment of the importance of experimental errors. (author)

  3. Disintegration constant of uranium-238 by spontaneous fission redetermined by glass track method

    International Nuclear Information System (INIS)

    Lima Medeiros, E. de.

    1978-01-01

    The disintegration constant of U 238 by spontaneous fission using glass as fission fragment detector was redetermined. A film of natural uranium (UO 3 ) prepared by chemical methods on the glass lamina was used in a long time experience of exposure (about 16 years). The good conditions of sample preparation and storage allow to observe, after chemical etching, fission fragment tracks. (M.C.K.) [pt

  4. Applications of nuclear track detectors

    International Nuclear Information System (INIS)

    Medveczky, L.

    1980-01-01

    The results of a scientific research-work are summarized. Nuclear track detectors were used for new applications or in unusual ways. Photographic films, nuclear emulsions and dielectric track detectors were investigated. The tracks were detected by optical microscopy. Empirical formulation has been derived for the neutron sensitivity of certain dielectric materials. Methods were developed for leak testing of closed alpha emitting sources. New procedures were found for the application and evaluation of track detector materials. The results were applied in the education, personnel dosimetry, radon dosimetry etc. (R.J.)

  5. Influence of tracks densities in solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Guedes O, S.; Hadler N.; Lunes, P.; Saenz T, C.

    1996-01-01

    When Solid State Nuclear Track Detectors (SSNTD) is employed to measure nuclear tracks produced mainly by fission fragments and alpha particles, it is considered that the tracks observation work is performed under an efficiency, ε 0 , which is independent of the track density (number of tracks/area unit). There are not published results or experimental data supporting such an assumption. In this work the dependence of ε 0 with track density is studied basing on experimental data. To perform this, pieces of CR-39 cut from a sole 'mother sheet' were coupled to thin uranium films for different exposition times and the resulting ratios between track density and exposition time were compared. Our results indicate that ε 0 is constant for track densities between 10 3 and 10 5 cm -2 . At our etching conditions track overlapping makes impossible the counting for densities around 1.7 x 10 5 cm -2 . For track densities less than 10 3 cm -2 , ε 0 , was not observed to be constant. (authors). 4 refs., 2 figs

  6. A position sensitive parallel plate avalanche fission detector for use in particle induced fission coincidence measurements

    NARCIS (Netherlands)

    Plicht, J. van der

    1980-01-01

    A parallel plate avalanche detector developed for the detection of fission fragments in particle induced fission reactions is described. The active area is 6 × 10 cm2; it is position sensitive in one dimension with a resolution of 2.5 mm. The detector can withstand a count rate of 25000 fission

  7. Thorium determination in water and biological materials by fission track

    International Nuclear Information System (INIS)

    Melo Ferreira, A.C. de.

    1989-01-01

    As a segment of a research programme on the study of bioaccumulation of radionuclides, in animals and vegetables from Morro do Ferro, Pocos de Caldas, MG, a fission track method for the determination of low levels of thorium in environmental samples was developed as an alternative for alpha spectroscopy. The study was carried out in early alpha spectroscopy samples, containing high levels of 228 Th activity, which makes difficult the 232 Th determination. A dry way method for thorium evaluation was developed. Pieces of membrane filters, containing La F 3 (Th), coupled to Makrofol detectors, were irradiated in the core of a research reactor, IEA-R1 (IPEN). (author)

  8. Processing of plastic track detectors

    International Nuclear Information System (INIS)

    Somogyi, G.

    1977-01-01

    A survey of some actual problems of the track processing methods available at this time for plastics is presented. In the case of the conventional chemical track-etching technique, mainly the etching situations related to detector geometry, and the relationship between registration sensitivity and the etching parameters are considered. Special attention is paid to the behaviour of track-revealing by means of electrochemical etching. Finally, some properties of a promising new track processing method based on graft polymerization are discussed. (author)

  9. Processing of plastic track detectors

    International Nuclear Information System (INIS)

    Somogyi, G.

    1976-01-01

    A survey of some actual problems of the track processing methods available at this time for plastics is presented. In the case of the conventional chemical track etching technique mainly the etching situations related to detector geometry and the relationship of registration sensitivity and the etching parameters are considered. A special attention is paid to the behaviour of track revealing by means of electrochemical etching. Finally, some properties of a promising new track processing method based on graft polymerization is discussed. (orig.) [de

  10. Liquid nitrogen enhancement of partially annealed fission tracks in glass

    International Nuclear Information System (INIS)

    Pilione, L.J.; Gold, D.P.

    1976-01-01

    It is known that the number density of fission tracks in solids is reduced if the sample is heated before chemical etching, and the effect of annealing must be allowed for before an age can be assigned to the sample. The extent of annealing can be determined by measuring the reduction of track parameters (diameter and/or length) and comparison with unannealed tracks. Correct ages can be obtained by careful calibration studies of track density reduction against track diameter or length reduction at different annealing temperatures and times. For crystallised minerals, however, the resulting correction techniques are not generally valid. In the experimental work described glass samples were partially annealed and then immersed in liquid N 2 for various periods, and it was shown that the properties of the glass and the track parameters could be altered so as to observe tracks that would normally be erased by annealing. The results of track density measurements against liquid N 2 immersion times are shown graphically. A gain of about 40% was achieved after 760 hours immersion time. The size of the tracks was not noticeably affected by the immersion. It was thought that thermal shock might be the cause of the track enhancement, but it was found that repeated immersion for about 2 hours did not lead to an increase in track density. Other studies suggest that the mechanism that erases the tracks through annealing may be partially reversed when the temperature of the sample is significantly lowered for a sufficient length of time. Further work is under way to find whether or not the process of enhancement is a reversal of the annealing process. Similar enhancement effects using liquid N 2 have been observed for d-particle tracks in polycarbonate detectors. (U.K.)

  11. Fission track imaging of the Australian continent

    International Nuclear Information System (INIS)

    Gleadow, A.; Kohn, B.; O'Sullivan, P.; Brown, R.; Gallagher, K.

    1999-01-01

    Full text: Techniques to reconstruct the thermal histories of rocks in the low-temperature environment of the upper crust have previously found important applications in such areas as sedimentary basin analysis, the evolution of convergent orogenic belts and studies of extensional tectonic environments. Increasingly large sets of thermochronology data are now becoming available on an even larger scale from the apatite fission-track system (for temperatures <∼110 deg C). Additional information is also now starting to emerge at even lower temperatures (<∼75 deg C) from the apatite (U-Th)/He system. The results from such systems can be used in novel ways to examine and visualise the evolution of the upper part of the continental crust. Quantitative modelling has brought a new dimension to this work and forward-modelling procedures are now well established which give 'best fit' thermal histories for temperatures less than about 110 deg C. In many cases the modelled thermal histories provide a proxy for rock transport towards the surface as overlying material is removed by denudation. Such information allows a reconstruction of the denudation history of the land surface. Applying these modelling procedures to large regional arrays of fission-track data means that the thermal history information can now be integrated with other regional data sets to provide an important new perspective on crustal and surface evolution. Apatite fission track analysis has now been completed on nearly 3000 surface outcrop samples across Australia under an AGCRC project to image the thermotectonic evolution of the exposed basement rocks of the continent. The samples analysed are mostly from rocks of broadly granitic composition and the apatites separated from these are overwhelmingly fluorapatites, which are consistent in their fission-track annealing properties with those on which the numerical annealing models are based. By interpolating the calculated thermal histories a series of

  12. Calibration of Nuclear Track Detectors

    International Nuclear Information System (INIS)

    Vukovic, J.B; Antanasijevic, R.; Novakovic, V.; Tasic, M.

    1998-01-01

    In this work we compare some of our preliminary results relating to the calibration Nuclear Track Detectors (NTD) with corresponding results obtained from other participants at the First International Intercomparison of Image Analyzers (III 97/98). Thirteen laboratories from Algeria, China, Czech Rep., France. Germany, Greece, Hungary, India, Italy, Mexico, Saudi Arabia, Slovenia and Yugoslavia participated in the III A 97/98. The NTD was 'Tustrack', Bristol. This type of CR-39 detector was etched by the organizer (J.Paltarey of al, Atomic Energy Research Institute, HPD, Budapest, Hungary). Etching condition was: 6N NaOH, 70 0C . Seven series detectors were exposed with the sources: B(n,a)Li, Am-241, Pu-Be(n,p), Radon and Am-Cm-Pu. Following parameters of exposed detectors were measured: track density of different sorts of tracks (circular, elliptical, track overlapping, their diameters, major and minor axis and other). (authors)

  13. Method of plastic track detector electrochemical etching

    International Nuclear Information System (INIS)

    D'yakov, A.A.

    1984-01-01

    The review of studies dealing with the development of the method for the electro-chemical etching (ECE) of the plastic track detectors on the base of polyethy-leneterephthalate (PET) and polycarbonate (PC) is given. Physical essence of the method, basic parameters of the processes, applied equipment and methods of measurement automation are considered. The advantages of the method over the traditional chemical etching are pointed out. Recommendations on the detector operation modes when detecting fission fragments, α-particles and fast neutrons are given. The ECE method is based on the condition that during chemical etching the high-voltage sound frequency alternating electric field is applied to the detector. In this case the detector serves as an isolating layer betWeen two vessels with etching solution in which high-voltage electrode are submerged. At a fixed electric field potential higher (over than the threshold value) at the end of the etching track cone atree-like discharge spot arises. It is shown that when PET is used for fast neutron detection it is advisable to apply for ECE the PEW solution (15g KOH+40 g C 2 H 2 OH + 45g H 2 O) the field potential should constitute 30 kVxcm -1 at the freqUency of 9 kHz. In the case of fission fragment detection Using ECE and PC the following ECE conditions are recommended: 30% KOH etcher, field potential of 10 kVxcm -1 , 2-4 kHz frequency. It is concluded that the ECE method permits considerably eXtend the sphere of plastic track detector application for detecting ionizing particles,

  14. Development of nuclear track detectors

    International Nuclear Information System (INIS)

    Somogyi, Gyoergy

    1985-01-01

    The birth and development of two decades of a new nuclear detection method is briefly summarized by one of the first inventors. The main steps of the development and broadening application of nuclear solid state track detectors are described underlying the contribution and main results of the research group of ATOMKI, Hungary (i.e. the finding of the proper plastic materials for track detectors, the discovery of correlations between the track diameter and the particle energy, the increasing of energy resolution, explanation of the track developing process, elaboration of new electrochemical track analyzing methods and automatic track analyzers). Recently, this detecting technique has grown to the phase of the industrial mass production and broad application in radiogeochemistry, mining, radioecology, personal monitoring in nuclear power plants, etc. (D.Gy.)

  15. Application of fission track analysis to hydrocarbon exploration

    International Nuclear Information System (INIS)

    Duddy, I.R.; Green, P.F.; Gleadow, A.J.W.; Marshallsea, S.; Tingate, P.; Laslett, G.M.; Hegarty, K.A.; Lovering, J.F.

    1985-01-01

    The temperature range over which fission tracks in apatite show observable annealing effects coincides with that responsible for the maximum generation of liquid hydrocarbons. Work is currently in progress in a number of Australian and overseas sedimentary basins, applying Apatite Fission Track Analysis (AFTA) to investigate the thermal evolution of these hydrocarbon prospective regions

  16. Uranium content of petroleum by fission track technique

    International Nuclear Information System (INIS)

    Paschoa, A.S.; Mafra, O.Y.; Oliveira, C.A.N. de; Pinto, L.R.

    1981-03-01

    The feasibility of the fission track registration technique to investigate the natural uranium concentration in petroleum is examined. The application of this technique to petroleum is briefly described and discussed critically. The results obtained so far indicate uranium concentrations in samples of Brazilian petroleum which are over the detect ion limit of fission track technique. (Author) [pt

  17. Cryogenic Tracking Detectors

    CERN Multimedia

    Luukka, P R; Tuominen, E M; Mikuz, M

    2002-01-01

    The recent advances in Si and diamond detector technology give hope of a simple solution to the radiation hardness problem for vertex trackers at the LHC. In particular, we have recently demonstrated that operating a heavily irradiated Si detector at liquid nitrogen (LN$_2$) temperature results in significant recovery of Charge Collection Efficiency (CCE). Among other potential benefits of operation at cryogenic temperatures are the use of large low-resistivity wafers, simple processing, higher and faster electrical signal because of higher mobility and drift velocity of carriers, and lower noise of the readout circuit. A substantial reduction in sensor cost could result The first goal of the approved extension of the RD39 program is to demonstrate that irradiation at low temperature in situ during operation does not affect the results obtained so far by cooling detectors which were irradiated at room temperature. In particular we shall concentrate on processes and materials that could significantly reduce th...

  18. Detector for gaseous nuclear fission products

    International Nuclear Information System (INIS)

    Kobayashi, Yoshihiro; Kubo, Katsumi.

    1979-01-01

    Purpose: To facilitate the fabrication of a precipitator type detector, as well as improve the reliability. Constitution: Gas to be measured flown in an anode is stored in a gas processing system. By applying a voltage between the anode and the cathode, if positively charged Rb or Cs which is the daughter products of gaseous fission products are present in the gas to be measured, the daughter products are successively deposited electrostatically to the cathode. The daughter products issue beta-rays and gamma-rays to ionize the argon gas at the anode, whereby ionizing current flows between both of the electrodes. Pulses are generated from the ionizing current, and presence or absence, as well as the amount of the gaseous fission products are determined by the value recorded for the number of the pulses to thereby detect failures in the nuclear fuel elements. After the completion of the detection, the inside of the anode is evacuated and the cathode is heated to evaporate and discharge the daughter products externally. This eliminates the effects of the former detection to the succeeding detection. (Moriyama, K.)

  19. Uranium content of petroleum by Fission track technique

    International Nuclear Information System (INIS)

    Paschaa, A.S.; Mafra, O.Y.; Oliveira, C.A.N.; Pinto, L.R.

    1982-01-01

    This paper examines the feasibility of the fission track registration technique to investigate the natural uranium concentration in petroleum. The application is briefly described and the results obtained indicate the presence of uranium concentrations in samples of Brazilian petroleum which are over the detection limit of the fission track technique. The irradiations were performed by using fluxes with predominance of thermal neutrons, which have a fission cross-section for U 235 equal to 579 barns. Since the neutron fluxes were not comp sed exclusively of thermal neutrons, fissions from fast neutrons would also be taken into account for U 238 and Th 232

  20. Fission-track ages and their geological interpretation

    International Nuclear Information System (INIS)

    Wagner, G.A.

    1981-01-01

    In fission-track dating, experimental procedures such as etching and thermal pre-treatment may strongly affect the age values determined and their geological interpretation. This peculiarity is due to the common phenomenon of partial fading of fossil (spontaneous-) fission tracks during a sample's geological history. The proper geological interpretation of the age data must take into account the specific experimental conditions, the stability characteristics and size distribution of fission tracks in the sample, the ages of co-existing minerals, and the independent information about the thermal history of the geological region. (author)

  1. Determination in soils of soluble uranium fraction in acid medium by fission tracks registration techniques

    International Nuclear Information System (INIS)

    Fernandes, G.P.

    1980-01-01

    The fission tracks registration technique was used to determine the concentration of uranium in soil solutions. The Makrofol KG, a synthetic plastic manufactured by Bayer, was used as a detector and the wet method was applied. The method was applied to a few samples of soils from Pocos de Caldas, Minas Gerais in Brazil. The concentrations of uranium in the samples and residues were also determined by other methods to compare the results obtained; only one sample showed deviation among the results obtained by the fission tracks method. (author)

  2. Dating of zircons by the fission track method

    International Nuclear Information System (INIS)

    Tenorio Hernandez, L.M.

    1992-01-01

    This work describes the methodology to date zircons by the Fission Track Method. A brief discussion is made of the physical principles of the method, physical properties of zircons and the geochemical properties of uranium. When starting with a hand sample, a mineral separation is required; to do this the following steps are needed: crushing and sieving of the sample, washing and drying, magnetic separation, heavy liquid separation (Bromoform 2.89 g/cm 3 , Diyodomethane = 3.31 g/cm 3 ), and manual separation on a stereoscopic microscope. Once the zircon concentrate is obtained, these are mounted on a FEP teflon mount, then polished and etched on an eutectic mix of 10 g. of KOH + 7.2 g. of NaOH, heated to 210 Centigrade degrees. Afterwards the mounts are prepared for irradiation, sterilizing and putting on top of them an external detector (a thin sheet of muscovite poor in uranium content). The package is then wrapped in plastic and sent to the reactor together with standard zircons of known age (Fish Canyon Tuff: Naeser et.al., 1981), mounted in the same way, plus standard glasses of known uranium content. The package was irradiated in a site known as SIRCA (Rotatory Capsules Irradiation System). Then the package is left to decay for several days, and then the external detectors are etched in a 48% concentrated hydrofluoric acid for 5 minutes. Once the samples are processed through the mentioned steps, spontaneous tracks appear in the zircons and induced tracks appear in the external detectors. On counting the tracks one obtains ρ s (spontaneous track density) and ρ 1 (induced track density). These two parameters together with another one called '#zeta #' (obtained from the standard zircons and glasses), are used to obtain the age of the sample. Zircons from Cerro de Mercado, Durango were dated and the age obtained was 30 ±5 Ma. This date is in agreement with similar results obtained by Fleisher and Naeser (1975) for zircons of the same locality and dated by the

  3. Application of pulse shape discrimination in Si detector for fission ...

    Indian Academy of Sciences (India)

    Pulse shape discrimination (PSD) with totally depleted transmission type Si surface barrier detector in reverse mount has been investigated to identify fission fragments in the presence of elastic background in heavy ion-induced fission reactions by both numerical simulation and experimental studies. The PSD method is ...

  4. Performance of ATLAS tracking detector

    CERN Document Server

    Lacuesta, V; The ATLAS collaboration

    2012-01-01

    The track and vertex reconstruction algorithms of the ATLAS Inner Detector have demonstrated excellent performance in the early data from the LHC. However, the rapidly increas- ing number of interactions per bunch crossing introduces new challenges both in computational aspects and physics performance. The combination of both silicon and gas based detectors provides high precision impact parameter and momentum measurement of charged particles, with high efficiency and small fake rate. Vertex reconstruction is used to identify with high efficiency the hard scattering process and to measure the amount of pile-up interactions, both aspects are cru- cial for many physics analyses. The performance of track and vertex reconstruction efficiency and resolution achieved in the 2011 and 2012 data-taking period are presented.

  5. Determination of the uranium concentration in soil solutions by the fission track registration technique

    International Nuclear Information System (INIS)

    Fernandes, G.P.

    1980-02-01

    The fission tracks registration technique was used to determine the uranium concentration in soil solutions. The Makrofol KG, a synthetic plastic manufactured by Bayer, was used as a detector and the wet method was applied. From the calibration curves obtained, it was possible to determine uranium concentrations in soil solutions, from 90 to 320 μg U/l, with an error between 9.4% and 4.0%, respectively. The method was applied to a few soil samples from Pocos de Caldas, Minas Gerais in Brazil. The uranium concentrations in the sample and residues were also determined by other methods to compare the results obtained; only one sample showed deviation from the results obtained by the fission tracks method. And this discrepancy was explained in a reasonable way. It was shown that the fission tracks technique can be used with sucess for application in soil solutions. (Author) [pt

  6. CR-39 as induced track detector in reactor: irradiation effect

    International Nuclear Information System (INIS)

    Zylberberg, H.

    1989-07-01

    A systematic study about reactor's neutrons radiation effect and gamma radiation effect on the properties of CR-39 that are significant for its use as induced fission track detector is showed. The following studies deserved attention: kinetics of the fission track chemical development; efficiency to register and to develop fission track; losses of developable tracks; variation in the number of developable tracks and variation in the visible and ultraviolet radiation spectrum. The dissertation is organized in seven specific chapters: solid state nuclear tracks (SSNT); CR-39 as SSNT; objectives and problems presentation; preparation and characterization of CR-39 as SSNT; gamma irradiation effect on the properties of CR-39 as SSNT; reactor neutron irradiation effect on the properties of CR-39 as SSNT and, results discussions and conclusions. The main work contributions are the use of CR-39 in the determination of fissionable nuclide as thorium and uranium in solid and liquid samples; gamma radiation damage on CR-39 as well as the reactor's neutron damage on CR-39. (B.C.A.) 62 refs, 53 figs, 21 tabs

  7. Induced fission track distribution from highly radioactive particles in fallout materials

    International Nuclear Information System (INIS)

    Hashimoto, Tetsuo; Okada, Tatemichi

    1987-01-01

    Some highly radioactive fallout particles (GPs) from the 19th Chinese nuclear detonation were followed to the neutron irradiation in a reactor after sandwiched with mica detectors. The interesting star-like fission track patterns were revealed on the etched surface of the mica detectors. The simple chemical separation procedure for the GPs was applied for the separation of U and Pu as fissile elements and the both resultant fractions were examined with the similar high sensitive fission tracking detection. Subsequently, a representative track pattern from a black spherical particle was subjected to the determination of fissile nuclide content; comparing the total fission events evaluated on the basis of the numerical calculation of track densities with the total thermal neutron fluence. The results implied that the uranium is responsible for the main fissile nuclide remaining within a particle as unfissioned fractions and should be certainly enriched with respect to U-235 within such small fallout particles. This sophisticated method was also applied to determine the dead GPs, which have been highly radioactive particles just after the detonations, in the rain and snow-residual materials. Many induced star-like fission tracks verified certainly that there remains a lot of dead particles in the atmosheric environment till nowadays. (author)

  8. Fission-track studies of uranium distribution in geological samples

    International Nuclear Information System (INIS)

    Brynard, H.J.

    1983-01-01

    The standard method of studying uranium distribution in geological material by registration of fission tracks from the thermal neutron-induced fission of 235 U has been adapted for utilisation in the SAFARI-1 reactor at Pelindaba. The theory of fission-track registration as well as practical problems are discussed. The method has been applied to study uranium distribution in a variety of rock types and the results are discussed in this paper. The method is very sensitive and uranium present in quantities far below the detection limit of the microprobe have been detected

  9. The relationship between fission track length and track density in apatite

    International Nuclear Information System (INIS)

    Laslett, G.M.; Gleadow, A.J.W.; Duddy, I.R.

    1984-01-01

    Fission track dating is based upon an age equation derived from a random line segment model for fission tracks. This equation contains the implicit assumption of a proportional relationship between the true mean length of fission tracks and their track density in an isotropic medium. Previous experimental investigation of this relationship for both spontaneous and induced tracks in apatite during progressive annealment model in an obvious fashion. Corrected equations relating track length and density for apatite, an anisotropic mineral, show that the proportionality in this case is between track density and a length factor which is a generalization of the mean track length combining the actual length and crystallographic orientation of the track. This relationship has been experimentally confirmed for induced tracks in Durango apatite, taking into account bias in sampling of the track lengths, and the effect of the bulk etching velocity. (author)

  10. Neutron activation analysis of uranium by means of electrochemical etching of tracks in lawsan detectors

    International Nuclear Information System (INIS)

    Kim Son Chun; Chuburkov, Yu.T.; Zvara, I.I.

    1982-01-01

    The method of neutron activation analysis of uranium in natural and artificial materials using track lavsan detectors of fission fragments has been developed. The method of electrochemical etching (etching reagent NaOH) of fragment tracks in lavsan is improved. Using statistical method of experiment planning the equation, describing the dependence of diometer value of fission fragment tracks on parameters of etching process, is obtained. The analysis sensitivity is 10 - 7 g/g - 10 - 8 g/g

  11. Detection of fission fragments and alpha particles using the solid trace detector CR-39

    International Nuclear Information System (INIS)

    Santos, R.C.

    1988-01-01

    The technique of detecting charged particles using the solid track detector CR-39 is employed to establish some characteristics of fission fragments and alpha particles emitted from a Cf-252 source. Results are presented and discussed on the following aspects i) distribution of the track diameters; ii) variations on the track diameters to the chemical attack; iii) variations of the chemical attack velocity with respect to concentration and temperature. iv) activation energy of the developping process; v) induction time; vi) critical angle and efficiency on track developping. (A.C.A.S.) [pt

  12. PHENIX central arm tracking detectors

    International Nuclear Information System (INIS)

    Adcox, K.; Ajitanand, N.N.; Alexander, J.; Autrey, D.; Averbeck, R.; Azmoun, B.; Barish, K.N.; Baublis, V.V.; Belkin, R.; Bhaganatula, S.; Biggs, J.C.; Borland, D.; Botelho, S.; Bryan, W.L.; Burward-Hoy, J.; Butsyk, S.A.; Chang, W.C.; Christ, T.; Dietzsch, O.; Drees, A.; Rietz, R. du; El Chenawi, K.; Evseev, V.A.; Fellenstein, J.; Ferdousi, T.; Fraenkel, Z.; Franz, A.; Fung, S.Y.; Gannon, J.; Garpman, S.; Godoi, A.L.; Greene, S.V.; Gustafsson, H.-A.; Harder, J.; Hemmick, T.K.; Heuser, J.M.; Holzmann, W.; Hutter, R.; Issah, M.; Ivanov, V.I.; Jacak, B.V.; Jagadish, U.; Jia, J.; Johnson, S.C.; Kandasamy, A.; Kann, M.R.; Kelley, M.A.; Khanzadeev, A.V.; Khomutnikov, A.; Komkov, B.G.; Kopytine, M.L.; Kotchenda, L.; Kotchetkov, D.; Kozlov, V.S.; Kravtsov, P.A.; Kudin, L.G.; Kuriatkov, V.V.; Lacey, R.; Lauret, J.; Lebedev, A.; Lebedev, V.D.; Li, X.H.; Libby, B.; Liccardi, W.; Machnowski, R.; Mahon, J.; Markushin, D.G.; Matathias, F.; Marx, M.D.; Messer, F.; Miftakhov, N.M.; Milan, J.; Miller, T.E.; Milov, A.; Minuzzo, K.; Mioduszewski, S.; Mitchell, J.T.; Muniruzzamann, M.; Nandi, B.K.; Negrin, J.; Nilsson, P.; Nystrand, J.; O'Brien, E.; O'Connor, P.; Oskarsson, A.; Oesterman, L.; Otterlund, I.; Pancake, C.E.; Pantuev, V.S.; Petersen, R.; Pinkenburg, C.H.; Pisani, R.P.; Purwar, A.K.; Rankowitz, S.; Ravinovich, I.; Riabov, V.G.; Riabov, Yu.G.; Rosati, M.; Rose, A.A.; Roschin, E.V.; Samsonov, V.M.; Sangster, T.C.; Seto, R.; Silvermyr, D.; Sivertz, M.; Smith, M.; Solodov, G.P.; Stenlund, E.; Takagui, E.M.; Tarakanov, V.I.; Tarasenkova, O.P.; Thomas, J.L.; Trofimov, V.A.; Tserruya, I.; Tydesjoe, H.; Velkovska, J.; Velkovsky, M.; Vishnevskii, V.I.; Vorobyov, A.A.; Vznuzdaev, E.A.; Vznuzdaev, M.; Wang, H.Q.; Weimer, T.; Wolniewicz, K.; Wu, J.; Xie, W.; Young, G.R.

    2003-01-01

    The PHENIX tracking system consists of Drift Chambers (DC), Pad Chambers (PC) and the Time Expansion Chamber (TEC). PC1/DC and PC2/TEC/PC3 form the inner and outer tracking units, respectively. These units link the track segments that transverse the RICH and extend to the EMCal. The DC measures charged particle trajectories in the r-phi direction to determine p T of the particles and the invariant mass of particle pairs. The PCs perform 3D spatial point measurements for pattern recognition and longitudinal momentum reconstruction and provide spatial resolution of a few mm in both r-phi and z. The TEC tracks particles passing through the region between the RICH and the EMCal. The design and operational parameters of the detectors are presented and running experience during the first year of data taking with PHENIX is discussed. The observed spatial and momentum resolution is given which imposes a limitation on the identification and characterization of charged particles in various momentum ranges

  13. Neutron detector for detecting rare events of spontaneous fission

    International Nuclear Information System (INIS)

    Ter-Akop'yan, G.M.; Popeko, A.G.; Sokol, E.A.; Chelnokov, L.P.; Smirnov, V.I.; Gorshkov, V.A.

    1981-01-01

    The neutron detector for registering rare events of spontaneous fission by detecting multiple neutron emission is described. The detector represents a block of plexiglas of 550 mm diameter and 700 mm height in the centre of which there is a through 160 mm diameter channel for the sample under investigation. The detector comprises 56 3 He filled counters (up to 7 atm pressure) with 1% CO 2 addition. The counters have a 500 mm length and a 32 mm diameter. The sampling of fission events is realized by an electron system which allows determining the number of detected neutrons, numbers of operated counters, signal amplitude and time for fission event detecting. A block diagram of a neutron detector electron system is presented and its operation principle is considered. For protection against cosmic radiation the detector is surronded by a system of plastic scintillators and placed behind the concrete shield of 6 m thickness. The results of measurements of background radiation are given. It has been found that the background radiation of single neutron constitutes about 150 counts per hour, the detecting efficiency of single neutron equals 0.483 +- 0.005, for a 10l detector sensitive volume. By means of the detector described the parameters of multiplicity distribution of prompt neutrons for 256 Fm spontaneous fission are measured. The average multiplicity equals 3.59+-0.06 the dispersion being 2.30+-0.65

  14. Thorium content of a mineral ore from Morro do Ferro by fission track technique

    International Nuclear Information System (INIS)

    Oliveira, C.A.N. de.

    1980-10-01

    The feasibility to determine thorium concentrations by fission track technique in samples of mineral ore has been demonstrated. The literature registers only the application of the fission track technique to mineral ore in the case where the fissionable element is uranium. The technique was applied to determine the thorium concentration of an ore sample from Morro do Ferro, taking advantage of the high thorium to uranium ratio in that mineral. The sample analysed presented a thorium concentration of 2467 +- 400 mg Th/Kg ore. The so called wet method was adopted by using the Bayer made Makrofol KG 10μm thick, as the detector foil, immersed in the thorium solution. The technique is also useful to determine thorium concentrations in environmental samples because of the following aspects: high sensitivity; fast chemical separation of interfering elements; low cost; and operational simplicity. (Author) [pt

  15. Development of the ZEUS central tracking detector

    Science.gov (United States)

    Brooks, C. B.; Bullock, F. W.; Cashmore, R. J.; Devenish, R. C.; Foster, B.; Fraser, T. J.; Gibson, M. D.; Gilmore, R. S.; Gingrich, D.; Harnew, N.; Hart, J. C.; Heath, G. P.; Hiddleston, J.; Holmes, A. R.; Jamdagni, A. K.; Jones, T. W.; Llewellyn, T. J.; Long, K. R.; Lush, G. J.; Malos, J.; Martin, N. C.; McArthur, I.; McCubbin, N. A.; McQuillan, D.; Miller, D. B.; Mobayyen, M. M.; Morgado, C.; Nash, J.; Nixon, G.; Parham, A. G.; Payne, B. T.; Roberts, J. H. C.; Salmon, G.; Saxon, D. H.; Sephton, A. J.; Shaw, D.; Shaw, T. B.; Shield, P. D.; Shulman, J.; Silvester, I.; Smith, S.; Strachan, D. E.; Tapper, R. J.; Tkaczyk, S. M.; Toudup, L. W.; Wallis, E. W.; Wastie, R.; Wells, J.; White, D. J.; Wilson, F. F.; Yeo, K. L.; ZEUS-UK Collaboration

    1989-11-01

    The design concept and development of the ZEUS central tracking detector is described. This is a cylindrical drift chamber designed for track reconstruction, electron identification and event triggering in a high-crossing-rate, high-magnetic-field environment.

  16. Development of the ZEUS central tracking detector

    International Nuclear Information System (INIS)

    Brooks, C.B.; Cashmore, R.J.; Gingrich, D.; Harnew, N.; Heath, G.P.; Holmes, A.R.; Martin, N.C.; McArthur, I.; Nash, J.; Salmon, G.; Shield, P.D.; Silvester, I.; Smith, S.; Wastie, R.; Wells, J.; Jamdagni, A.K.; McQuillan, D.; Miller, D.B.; Mobayyen, M.M.; Shulman, J.; Toudup, L.W.

    1989-01-01

    The design concept and development of the ZEUS central tracking detector is described. This is a cylindrical drift chamber designed for track reconstruction, electron identification and event triggering in a high-crossing-rate, high-magnetic-field environment. (orig.)

  17. Neutron threshold activation detectors (TAD) for the detection of fissions

    Science.gov (United States)

    Gozani, Tsahi; Stevenson, John; King, Michael J.

    2011-10-01

    Prompt fission neutrons are one of the strongest signatures of the fission process. Depending on the fission inducing radiation, their average number ranges from 2.5 to 4 neutrons per fission. They are more energetic and abundant, by about 2 orders of magnitude, than the delayed neutrons (≈3 vs. ≈0.01) that are commonly used as indicators for the presence of fissionable materials. The detection of fission prompt neutrons, however, has to be done in the presence of extremely intense probing radiation that stimulated them. During irradiation, the fission stimulation radiation, X-rays or neutrons, overwhelms the neutron detectors and temporarily incapacitate them. Consequently, by the time the detectors recover from the source radiation, fission prompt neutrons are no longer emitted. In order to measure the prompt fission signatures under these circumstances, special measures are usually taken with the detectors such as heavy shielding with collimation, use of inefficient geometries, high pulse height bias and gamma-neutron separation via pulse-shape discrimination with an appropriate organic scintillator. These attempts to shield the detector from the flash of radiation result in a major loss of sensitivity. It can lead to a complete inability to detect the fission prompt neutrons. In order to overcome the blinding induced background from the source radiation, the detection of prompt fission neutrons needs to occur long after the fission event and after the detector has fully recovered from the source overload. A new approach to achieve this is to detect the delayed activation induced by the fission neutrons. The approach demonstrates a good sensitivity in adverse overload situations (gamma and neutron "flash") where fission prompt neutrons could normally not be detected. The new approach achieves the required temporal separation between the detection of prompt neutrons and the detector overload by the neutron activation of the detector material. The technique

  18. Neutron threshold activation detectors (TAD) for the detection of fissions

    International Nuclear Information System (INIS)

    Gozani, Tsahi; Stevenson, John; King, Michael J.

    2011-01-01

    Prompt fission neutrons are one of the strongest signatures of the fission process. Depending on the fission inducing radiation, their average number ranges from 2.5 to 4 neutrons per fission. They are more energetic and abundant, by about 2 orders of magnitude, than the delayed neutrons (∼3 vs. ∼0.01) that are commonly used as indicators for the presence of fissionable materials. The detection of fission prompt neutrons, however, has to be done in the presence of extremely intense probing radiation that stimulated them. During irradiation, the fission stimulation radiation, X-rays or neutrons, overwhelms the neutron detectors and temporarily incapacitate them. Consequently, by the time the detectors recover from the source radiation, fission prompt neutrons are no longer emitted. In order to measure the prompt fission signatures under these circumstances, special measures are usually taken with the detectors such as heavy shielding with collimation, use of inefficient geometries, high pulse height bias and gamma-neutron separation via pulse-shape discrimination with an appropriate organic scintillator. These attempts to shield the detector from the flash of radiation result in a major loss of sensitivity. It can lead to a complete inability to detect the fission prompt neutrons. In order to overcome the blinding induced background from the source radiation, the detection of prompt fission neutrons needs to occur long after the fission event and after the detector has fully recovered from the source overload. A new approach to achieve this is to detect the delayed activation induced by the fission neutrons. The approach demonstrates a good sensitivity in adverse overload situations (gamma and neutron 'flash') where fission prompt neutrons could normally not be detected. The new approach achieves the required temporal separation between the detection of prompt neutrons and the detector overload by the neutron activation of the detector material. The technique

  19. Neutron threshold activation detectors (TAD) for the detection of fissions

    Energy Technology Data Exchange (ETDEWEB)

    Gozani, Tsahi, E-mail: tgozani@rapiscansystems.com [Rapiscan Laboratories, Inc., 520 Almanor Ave., Sunnyvale, CA 94085 (United States); Stevenson, John; King, Michael J. [Rapiscan Laboratories, Inc., 520 Almanor Ave., Sunnyvale, CA 94085 (United States)

    2011-10-01

    Prompt fission neutrons are one of the strongest signatures of the fission process. Depending on the fission inducing radiation, their average number ranges from 2.5 to 4 neutrons per fission. They are more energetic and abundant, by about 2 orders of magnitude, than the delayed neutrons ({approx}3 vs. {approx}0.01) that are commonly used as indicators for the presence of fissionable materials. The detection of fission prompt neutrons, however, has to be done in the presence of extremely intense probing radiation that stimulated them. During irradiation, the fission stimulation radiation, X-rays or neutrons, overwhelms the neutron detectors and temporarily incapacitate them. Consequently, by the time the detectors recover from the source radiation, fission prompt neutrons are no longer emitted. In order to measure the prompt fission signatures under these circumstances, special measures are usually taken with the detectors such as heavy shielding with collimation, use of inefficient geometries, high pulse height bias and gamma-neutron separation via pulse-shape discrimination with an appropriate organic scintillator. These attempts to shield the detector from the flash of radiation result in a major loss of sensitivity. It can lead to a complete inability to detect the fission prompt neutrons. In order to overcome the blinding induced background from the source radiation, the detection of prompt fission neutrons needs to occur long after the fission event and after the detector has fully recovered from the source overload. A new approach to achieve this is to detect the delayed activation induced by the fission neutrons. The approach demonstrates a good sensitivity in adverse overload situations (gamma and neutron 'flash') where fission prompt neutrons could normally not be detected. The new approach achieves the required temporal separation between the detection of prompt neutrons and the detector overload by the neutron activation of the detector

  20. Estimation of trace levels of plutonium in urine samples by fission track technique

    International Nuclear Information System (INIS)

    Sawant, P.D.; Prabhu, S.; Pendharkar, K.A.; Kalsi, P.C.

    2009-01-01

    Individual monitoring of radiation workers handling Pu in various nuclear installations requires the detection of trace levels of plutonium in bioassay samples. It is necessary to develop methods that can detect urinary excretion of Pu in fraction of mBq range. Therefore, a sensitive method such as fission track analysis has been developed for the measurement of trace levels of Pu in bioassay samples. In this technique, chemically separated plutonium from the sample and a Pu standard were electrodeposited on planchettes and covered with Lexan solid state nuclear track detector (SSNTD) and irradiated with thermal neutrons in APSARA reactor of Bhabha Atomic Research Centre, India. The fission track densities in the Lexan films of the sample and the standard were used to calculate the amount of Pu in the sample. The minimum amount of Pu that can be analyzed by this method using doubly distilled electronic grade (E. G.) reagents is about 12 μBq/L. (author)

  1. The changing face of fission track dating: recent advances

    International Nuclear Information System (INIS)

    Green, P.F.; Duddy, I.R.; Gleadow, A.J.W.; Laslett, G.M.; Hegarty, K.A.; Lovering, J.F.

    1985-01-01

    Fission Track Dating has undergone something of a renaissance in recent years. What began as a rather unreliable method of geochronology has now become a rigorous and dependable means of measuring not only geological time but also paleotemperatures. Developments such as the zeta calibration technique, rigorous satistical data analysis, investigation of confined track lengths and detailed studies of annealing behaviour have all contributed to advances in the technique

  2. The analysis of projected fission track lengths

    International Nuclear Information System (INIS)

    Laslett, G.M.; Galbraith, R.F.; Green, P.F.

    1994-01-01

    This article deals with the question of how features of the thermal history can be estimated from projected track length measurements, i.e. lengths of the remaining parts of tracks that have intersected a surface, projected onto that surface. The appropriate mathematical theory is described and used to provide a sound basis both for understanding the nature of projected length measurements and for analysing observed data. The estimation of thermal history parameters corresponding to the current temperature, the maximum palaeotemperature and the time since cooling, is studied using laboratory data and simulations. In general the information contained in projected track lengths and angles is fairly limited, compared, for example, with that from a much smaller number of confined tracks, though we identify some circumstances when such measurements may be useful. Also it is not straightforward to extract the information and simple ad hoc estimation methods are generally inadequate. (author)

  3. Fission-track evidence of tectonic evolution in the northwestern ...

    Indian Academy of Sciences (India)

    Guo-Qiang Sun

    2018-02-14

    Feb 14, 2018 ... from further collision of the Indian and Eurasian plates along the Yarlung Tsangpo suture zone. Strata ... Kunlun orogenic belt system using fission-track analysis of ... which had a decisive role in the development and ... boundary of the basin (Yue et al. ... Tagh fault commenced strike-slip movement (Yue.

  4. Influence of the cosmic-ray induced fission tracks on the fission track of extraterrestric minerals via the 238U spontaneous fission

    International Nuclear Information System (INIS)

    Damm, G.; Thiel, K.

    1977-01-01

    The age determined by counting fission tracks of lunar and meteorite materials is obviously falsified by additional fission track parts not to be accounted for by the spontaneous fission of uranium 238. For this p and n induced fissions of U, Th and other hreavy elements through the cosmic radiation come into consideration. In order to determine the possible part of such interference factors, a simulation experiment at the proton synchrocycloton (CERN, Geneva) has been carried out and independently of this, the production rates for the p and n induced U, Th, Bi, Pb and Au in the surface-near regolith layers of the moon were calculated. It could be seen that the irradiation age as well as the spacial distribution of the heavy metals in the samples to be dated must be considered. (RB) [de

  5. Chemical etching of fission tracks in ethylene-tetrafluoroethylene copolymer

    International Nuclear Information System (INIS)

    Komaki, Y.; Tsujimura, S.; Seguchi, T.

    1979-01-01

    The chemical etching of fission tracks in ethylene-tetrafluoroethylene copolymer was studied. Etched holes 3000 to 4000 A in diameter were recognized by electron microscopy for a film bombarded by fission fragments in oxygen and etched in a 12N sodium hydroxide solution at 125 0 C. The radial etching rate at 125 0 C was 6 to 8 A/hr, which is less than 17 A/hr for polyvinylidene fluoride in the same sodium hydroxide concentration at 85 0 C. The smaller rate is a reflection of the larger chemical resistivity of ethylene-tetrafluoroethylene copolymer than polyvinylidene fluoride. (author)

  6. Development of the fission fragment track registration technique for the determination of the uranium contamination

    International Nuclear Information System (INIS)

    Tanaka, E.M.

    1979-01-01

    The Fission Fragment Track Registration Technique is developed to measure the uranium concentration about microgram of uranium per litre of liquid samples. The drying method of drops on the detector (Makrofol KG) and a special sampling procedure to avoid the cumbersome high density of tracks formation at the edge of the deposition surface as a 'ring' is adopted. The samples are irradiated by neutrons produced by the IEA-R1 Reactor (thermal neutron flux about 10 12 neutrons/cm 2 .s) inducing the uranium fission. The tracks registered by the fission fragments in the detector are chemically enlarged and counted by an automatic couting system. By this method the uranium concentrations ranging from 0,9 to 7,6 microgram of uranium per litre, can be determined with precisions between 2,7% the greater and 23% to the lower concentration. The uranium concentration measurements in human hair and urine are made showing that this method is very useful to control and detect eventual uranium contamination [pt

  7. Fission track analysis of Pu in small specimens of biological material: Technical progress report, August 1, 1987--July 31, 1988

    International Nuclear Information System (INIS)

    Wrenn, M.E.

    1988-01-01

    The objective of this research is to develop a highly specific and ultrasensitive method capable of detecting 100 aCi/liter of 239 Pu in human urine. The method using neutron induced fission track analysis is to be made free of interference from uranium, the only naturally occurring element with an isotope which fissions with thermal neutrons. A simplified flow diagram for the method is shown in Figure 1. Briefly 239 Pu is coprecipitated quantitatively from urine with rhodozonic acid. The precipitate containing the 239 Pu is dissolved in HCl and is sequentially passed through two ion exchange columns and reduced in volume. The element is then deposited in a circular area on a thick polycarbonate detector and a thinner detector is placed over the circular deposit. The plastic detectors are then irradiated to a high thermal neutron fluence in a research reactor. The detectors are etched in a caustic solution for controlled times and temperatures in order to develop the fission tracks. Images of tracks are formed both on the thin and thick plastic detectors. Total tracks in the thinner detector are measured with a locally developed spark counter and in the thick plastic are measured by counting with a microscope. The results will be made quantitative by constructing a calibration curve for 239 Pu. 3 refs., 9 figs., 3 tabs

  8. Nanoscale measurements of proton tracks using fluorescent nuclear track detectors

    Energy Technology Data Exchange (ETDEWEB)

    Sawakuchi, Gabriel O., E-mail: gsawakuchi@mdanderson.org; Sahoo, Narayan [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 and Graduate School of Biomedical Sciences, The University of Texas, Houston, Texas 77030 (United States); Ferreira, Felisberto A. [Department of Nuclear Physics, University of Sao Paulo, SP 05508-090 (Brazil); McFadden, Conor H. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Hallacy, Timothy M. [Biophysics Program, Harvard University, Cambridge, Massachusetts 02138 (United States); Granville, Dal A. [Department of Medical Physics, The Ottawa Hospital Cancer Centre, Ottawa, Ontario K1H 8L6 (Canada); Akselrod, Mark S. [Crystal Growth Division, Landauer, Inc., Stillwater, Oklahoma 74074 (United States)

    2016-05-15

    Purpose: The authors describe a method in which fluorescence nuclear track detectors (FNTDs), novel track detectors with nanoscale spatial resolution, are used to determine the linear energy transfer (LET) of individual proton tracks from proton therapy beams by allowing visualization and 3D reconstruction of such tracks. Methods: FNTDs were exposed to proton therapy beams with nominal energies ranging from 100 to 250 MeV. Proton track images were then recorded by confocal microscopy of the FNTDs. Proton tracks in the FNTD images were fit by using a Gaussian function to extract fluorescence amplitudes. Histograms of fluorescence amplitudes were then compared with LET spectra. Results: The authors successfully used FNTDs to register individual proton tracks from high-energy proton therapy beams, allowing reconstruction of 3D images of proton tracks along with delta rays. The track amplitudes from FNTDs could be used to parameterize LET spectra, allowing the LET of individual proton tracks from therapeutic proton beams to be determined. Conclusions: FNTDs can be used to directly visualize proton tracks and their delta rays at the nanoscale level. Because the track intensities in the FNTDs correlate with LET, they could be used further to measure LET of individual proton tracks. This method may be useful for measuring nanoscale radiation quantities and for measuring the LET of individual proton tracks in radiation biology experiments.

  9. SAPhIR: a fission-fragment detector

    International Nuclear Information System (INIS)

    Theisen, Ch.; Gautherin, C.; Houry, M.; Korten, W.; Le Coz, Y.; Lucas, R.; Barreau, G.; Doan, T. P.; Belier, G.; Meot, V.; Ethvignot, Th.; Cahan, B.; Le Coguie, A.; Coppolani, X.; Delaitre, B.; Le Bourlout, P.; Legou, Ph.; Maillard, O.; Durand, G.; Bouillac, A.

    1998-01-01

    SAPhIR is the acronym for S a clay A q uitaine P ho tovoltaic cells for I s omer R e search. It consists of solar cells, used for fission-fragment detection. It is a collaboration between 3 laboratories: CEA Saclay, CENBG Bordeaux and CEA Bruyeres le Chatel. The coupling of a highly efficient fission-fragment detector like SAPhIR with EUROBALL will provide new insights in the study of very deformed nuclear matter and in the spectroscopy of neutron-rich nuclei

  10. p- and n-induced U-fission tracks as possible error sources in the fission track dating of extraterrestric samples

    International Nuclear Information System (INIS)

    Thiel, K.

    1975-01-01

    Using the fission track dating method by means of uranium fission tracks in meteorites and moon samples (according to the successful Apollo and Luna missions), special problems arise, as the samples frequently have a very great age and were subjected to the inmediate effect of primary cosmic radiation. To determine the share of induced fission tracks, an extended 'cosmic ray' simulation experiment was carried out on the p-synchrocyclotron in CERN, Geneva; the performance and results of the test with the proton flux and U fission track measurements are dealt with in detail. (HK/LH) [de

  11. Inverse modelling of thermal histories with apatite fission tracks

    International Nuclear Information System (INIS)

    El Lmrani, A.; Zine El Abidine, H.; Limouri, M.; Essaid, A.; POupeau, G.

    1998-01-01

    The problem of modelling thermal histories lies in the exploration of a time-temperature space, usually so broad, in order to identify the optimal paths. For overcoming this difficulty, many approaches were proposed, using linear and non-linear optimisation algorithms. Generally, these approaches do not take into account the experimental data (fission track age [FTA] and fission track length distribution [FTLD]) to better aim the search strategy. The present work shows that experimental data hold some precious information, for which it should be known how to extract it. In fact, it allows us to tighten the time-temperature space of search, supposed to contain the optimal solutions. A genetic algorithm is also used in this work to perform the search for these optimal solutions. (authors)

  12. Using track detectors in neutron dosimetry

    International Nuclear Information System (INIS)

    Spurny, F.; Turek, K.

    1977-01-01

    The usage of track detectors of charged particles provides a new possibility of neutron dosimetry. Presented is a comparison of the main dosimetric characteristics of three various types of track detectots of fast neutrons, i.e. glass in the contact with 232 Th; KODAK LR115 cellulose nitrate; MAKROFOL E polycarbonate. Results of studing energy dependences of detectors are presented. Results obtained using phantoms under radiation fields of various sources of complex gamma-neutron radiation are discussed [ru

  13. Study on the technical feasibility of Fission-Track dating at two irradiation positions of the RA-6 research reactor

    International Nuclear Information System (INIS)

    Dorval, Eric

    2005-01-01

    The method of Fission-Track dating is based upon the detection of the damage caused by fission fragments from the Uranium contained in geological samples.In order to determine the age of a sample, both the amount of spontaneous fissions occurred and the Uranium concentration must be known.The latter requires the irradiation of the samples inside a reactor with a well-thermalized flux, so that fissions are induced over 235 U targets only. Therefore, the Uranium concentration may be determined.The main inconvenient presented by the irradiation sites at the RA-6 MTR-type reactor is that neutron flux is not completely thermal there, which means that fissions due to epithermal and fast neutrons will not be negligible.In the same way, tracks due to fissions of 238 U and 232 Th will be detected. In order to know the corrections that must be applied to those measurements performed in this reactor, it is necessary to characterize fast flux.Because of it, this laboratory's gamma spectrometry equipment had to be calibrated. After that, several activation detectors were irradiated and results were analyzed. Finally, it was determined that it is feasible to Fission-Track date at the I6 position. However, limitations associated to this method were analyzed for the values of flux measured in the different sites

  14. Obsidian ages from Ecuador by the fission track dating

    International Nuclear Information System (INIS)

    Osorio, A.M.; Hadler, J.C.; Bigazzi, G.; Norelli, P.; Coltelli, M.; Salazar, E.

    1991-01-01

    Fission track dating was applied in order to study obsidian samples originated from Mullumica and Callejones flows, Oyacachi, Ecuador. Preliminary data show that the ratio between the mean diameter os spontaneous and induced tracks is about 0.9, an indication that the analysed samples were submitted to small fading during their geological histories. Ages were obtained around 0.2 x 10 6 a, in agreement with Miller and Wagners's results. Ages ranging from 0.17 x 10 6 a up to 0.23 x 10 6 a were obtained correcting the apparent ages by means of the plateau method. (author)

  15. Industrial development of neutron detectors, fission chambers, self powered detectors, ionization chambers

    International Nuclear Information System (INIS)

    Constans, H.; Coville, P.; Guerre, J.

    1975-01-01

    Reactor control requires the determination of neutron flux at all times. The needed characteristics lead to use of several types of detectors: boron lined counters, boron lined ionization chambers, fission ionization chambers and self powered detectors. The principle of the reaction involved the fabrication requirements, the different modes of utilization and the characteristics obtained are examined for each detector. The problem of electric connections in the active area has been solved by developing ''integrated cables'' [fr

  16. Thermal significance of fission-track length distributions

    International Nuclear Information System (INIS)

    Crowley, K.D.

    1985-01-01

    The semi-analytical solution of an equation describing the production and shortening of fission tracks in apatite suggests that certain thermal histories have unique length-distribution 'signatures'. Isothermal-heating histories should be characterized by flattened, length-shortened distributions; step-heating histories should be characterized by bimodal track length distributions; and linear-cooling histories should be characterized by negatively skewed, length-shortened distributions. The model formulated here to investigate track length distributions can be used to constrain the thermal histories of natural samples for which unbiased track length data are available - provided that the geologic history of the system of interest can be used to partially constrain one of the unknowns in the model equations, time or temperature. (author)

  17. Optical efficiency for fission fragment track counting in Muscovite solid state track recorders

    International Nuclear Information System (INIS)

    Roberts, J.H.; Ruddy, F.H.; Gold, R.

    1984-01-01

    In order to determine absolute fission rates from thin actinide deposits placed in direct contact with Muscovite Solid State Track Recorders, it is necessary to know the efficiency with which fission fragment tracks are recorded. In this paper, a redetermination of the 'optical efficiency', i.e. the fraction of fission events recorded and observed in the Muscovite is reported. The value obtained from a well-calibrated thin deposit of 252 Cf and Muscovite etched about 90 min. in 49% HF at room temperature, is 0.9875 +- 0.0085. Manual counting was used. Preliminary results from a deposit of 242 Pu are also reported, along with preliminary comparisons of track counting with an automated system. Reasons for the discrepancy of the optical efficiency reported here with an earlier measurement are also reported. (author)

  18. Optical efficiency for fission-fragment track counting in Muscovite Solid-State Track Recorders

    International Nuclear Information System (INIS)

    Roberts, J.H.; Ruddy, F.H.; Gold, R.

    1983-07-01

    In order to determine absolute fission rates from thin actinide deposits placed in direct contact with Muscovite Solid-State Track Recorders, it is necessary to know the efficiency with which fission-fragment tracks are recorded. In this paper, a redetermination of the optical efficiency, i.e., the fraction of fission events recorded and observed in the Muscovite, is reported. The value obtained from a well-calibrated thin deposit of 252 Cf and Muscovite etched about 90 min. in 49% HF at room temperature, is 0.9875 +- 0.0085. Manual counting was used. Preliminary results from a deposit of 242 Pu are also reported, along with preliminary comparisons of track counting with an automated system. Reasons for the discrepancy of the optical efficiency reported here with an earlier measurement are also reported. 5 references, 1 figure, 3 tables

  19. Cerenkov Detectors for Fission Product Monitoring in Reactor Coolant Water

    Energy Technology Data Exchange (ETDEWEB)

    Strindehag, O

    1967-09-15

    The expected properties of Cerenkov detectors when used for fission product monitoring in water cooled reactors and test loops are discussed from the point of view of the knowledge of the sensitivity of these detectors to some beta emitting isotopes. The basic theory for calculation of the detector response is presented, taking the optical transmission in the sample container and the properties of the photomultiplier tube into account. Special attention is paid to the energy resolution of this type of Cerenkov detector. For the design of practical detectors the results from several investigations of various window and reflector materials are given, and the selection of photomultiplier tubes is briefly discussed. In the case of optical reflectors and photomultiplier tubes reference is made to two previous reports by the author. The influence of the size and geometry of the sample container on the energy resolution follows from a separate investigation, as well as the relative merits of sample containers with transparent inner walls. Provided that the energy resolution of the Cerenkov detector is sufficiently high, there are several reasons for using this detector type for failed-fuel-element detection. It seems possible to attain the desired energy resolution by careful detector design.

  20. Application of fission track technique for estimation of uranium concentration in drinking waters of Punjab

    International Nuclear Information System (INIS)

    Prabhu, S.P.; Sawant, P.D.; Raj, S.S.; Kumar, A.; Sarkar, P.K.; Tripathi, R.M.

    2012-01-01

    Drinking water samples were collected from four different districts, namely Bhatinda, Mansa, Faridkot and Firozpur, of Punjab for ascertaining the U(nat.) concentrations. All samples were preserved, processed and analyzed by laser fluorimetry (LF). To ensure accuracy of the data obtained by LF, few samples (10 nos) from each district were analyzed by alpha spectrometry as well as by fission track analysis (FTA) technique. For FTA technique few μl of water sample was transferred to polythene tube, lexan detector was immersed in it and the other end of the tube was also heat-sealed. Two samples and one uranium standard were irradiated in DHRUVA reactor. Irradiated detectors were chemically etched and tracks counted using an optical microscope. Uranium concentrations in samples ranged from 3.2 to 60.5 ppb and were comparable with those observed by LF. (author)

  1. Kit with track detectors aiming at didactic

    International Nuclear Information System (INIS)

    Cesar, M.F.; Koskinas, M.F.

    1988-01-01

    The kit intends to improve the possibilities in performing experiments of Nuclear Physics in Modern Physics Laboratories of Physics Course introducing the solid state nuclear track detectors. In these materials the passage of heavily ionizing nuclear particles creates paths (tracks) that may be revealed and made visible in an optical microscope. By the help of the kit several experiments and/or demonstrations may be performed. The kit contains solid state nuclear track detectors unirradiated and irradiated, irradiated etched and uneteched sheets; an alpha source of 241 Am and an instrution text with photomicrographs. To use the kit the laboratory must have an ordinary optical microscope. (author) [pt

  2. Multiplicity counting from fission detector signals with time delay effects

    Science.gov (United States)

    Nagy, L.; Pázsit, I.; Pál, L.

    2018-03-01

    In recent work, we have developed the theory of using the first three auto- and joint central moments of the currents of up to three fission chambers to extract the singles, doubles and triples count rates of traditional multiplicity counting (Pázsit and Pál, 2016; Pázsit et al., 2016). The objective is to elaborate a method for determining the fissile mass, neutron multiplication, and (α, n) neutron emission rate of an unknown assembly of fissile material from the statistics of the fission chamber signals, analogous to the traditional multiplicity counting methods with detectors in the pulse mode. Such a method would be an alternative to He-3 detector systems, which would be free from the dead time problems that would be encountered in high counting rate applications, for example the assay of spent nuclear fuel. A significant restriction of our previous work was that all neutrons born in a source event (spontaneous fission) were assumed to be detected simultaneously, which is not fulfilled in reality. In the present work, this restriction is eliminated, by assuming an independent, identically distributed random time delay for all neutrons arising from one source event. Expressions are derived for the same auto- and joint central moments of the detector current(s) as in the previous case, expressed with the singles, doubles, and triples (S, D and T) count rates. It is shown that if the time-dispersion of neutron detections is of the same order of magnitude as the detector pulse width, as they typically are in measurements of fast neutrons, the multiplicity rates can still be extracted from the moments of the detector current, although with more involved calibration factors. The presented formulae, and hence also the performance of the proposed method, are tested by both analytical models of the time delay as well as with numerical simulations. Methods are suggested also for the modification of the method for large time delay effects (for thermalised neutrons).

  3. Automatic measurement for solid state track detectors

    International Nuclear Information System (INIS)

    Ogura, Koichi

    1982-01-01

    Since in solid state track detectors, their tracks are measured with a microscope, observers are forced to do hard works that consume time and labour. This causes to obtain poor statistic accuracy or to produce personal error. Therefore, many researches have been done to aim at simplifying and automating track measurement. There are two categories in automating the measurement: simple counting of the number of tracks and the requirements to know geometrical elements such as the size of tracks or their coordinates as well as the number of tracks. The former is called automatic counting and the latter automatic analysis. The method to generally evaluate the number of tracks in automatic counting is the estimation of the total number of tracks in the total detector area or in a field of view of a microscope. It is suitable for counting when the track density is higher. The method to count tracks one by one includes the spark counting and the scanning microdensitometer. Automatic analysis includes video image analysis in which the high quality images obtained with a high resolution video camera are processed with a micro-computer, and the tracks are automatically recognized and measured by feature extraction. This method is described in detail. In many kinds of automatic measurements reported so far, frequently used ones are ''spark counting'' and ''video image analysis''. (Wakatsuki, Y.)

  4. The Cosmic Ray Tracking (CRT) detector system

    International Nuclear Information System (INIS)

    Bernloehr, K.; Gamp, S.; Hermann, G.; Hofmann, W.; Kihm, T.; Knoeppler, J.; Leffers, G.; Matheis, V.; Panter, M.; Trunk, U.; Ulrich, M.; Wolf, T.; Zink, R.; Heintze, J.

    1996-01-01

    The Cosmic Ray Tracking (CRT) project represents a study on the use of tracking detectors of the time projection chamber type to detect secondary cosmic ray particles in extensive air showers. In reconstructing the arrival direction of the primary cosmic ray particles, the CRT detectors take advantage of the angular correlation of secondary particles with the cosmic rays leading to these air showers. In this paper, the detector hardware including the custom-designed electronics system is described in detail. A CRT detector module provides an active area of 2.5 m 2 and allows to measure track directions with a precision of 0.4 circle . It consists of two circular drift chambers of 1.8 m diameter with six sense wires each, and a 10 cm thick iron plate between the two chambers. Each detector has a local electronics box with a readout, trigger, and monitoring system. The detectors can distinguish penetrating muons from other types of charged secondaries. A large detector array could be used to search for γ-ray point sources at energies above several TeV and for studies of the cosmic-ray composition. Ten detectors are in operation at the site of the HEGRA air shower array. (orig.)

  5. The fission-track analysis: An alternative technique for provenance studies of prehistoric obsidian artefacts

    CERN Document Server

    Bellot-Gurlet, L; Dorighel, O; Oddone, M; Poupeau, G; Yegingil, Z

    1999-01-01

    Comparison of fission-track parameters - age and track densities - is an alternative tool for correlating obsidian artefacts with their potential natural sources. This method was applied by different fission-track groups in various regions and results were compared with those obtained using the more popular provenance identification techniques based on chemical composition studies. Hundreds of analyses prove that fission-track dating is a complementary technique which turns out to be very useful, specially when the chemical composition does not fully discriminate different sources. Archaeologically significant results were obtained applying the fission-track analysis in various regions of earth.

  6. The fission-track analysis: An alternative technique for provenance studies of prehistoric obsidian artefacts

    International Nuclear Information System (INIS)

    Bellot-Gurlet, L.; Bigazzi, G.; Dorighel, O.; Oddone, M.; Poupeau, G.; Yegingil, Z.

    1999-01-01

    Comparison of fission-track parameters - age and track densities - is an alternative tool for correlating obsidian artefacts with their potential natural sources. This method was applied by different fission-track groups in various regions and results were compared with those obtained using the more popular provenance identification techniques based on chemical composition studies. Hundreds of analyses prove that fission-track dating is a complementary technique which turns out to be very useful, specially when the chemical composition does not fully discriminate different sources. Archaeologically significant results were obtained applying the fission-track analysis in various regions of earth

  7. Effect of track etch rate on geometric track characteristics for polymeric track detectors

    International Nuclear Information System (INIS)

    Abdel-Naby, A.A.; El-Akkad, F.A.

    2001-01-01

    Analysis of the variable track etch rate on geometric track characteristic for polymeric track detectors has been applied to the case of LR-155 II SSNTD. Spectrometric characteristics of low energy alpha particles response by the polymeric detector have been obtained. The track etching kinematics theory of development of minor diameter of the etched tracks has been applied. The calculations show that, for this type of detector, the energy dependence of the minor track diameter d is linear for small-etched removal layer h. The energy resolution gets better for higher etched removal layer

  8. Studies on the Th biodistribution in internal contamination by the fission track method using animals

    International Nuclear Information System (INIS)

    Ciubotariu, M.; Danis, A.; Dumitrescu, G.; Cucu, M.

    1998-01-01

    In our previous studies on the U internal contamination, qualitative and quantitative results were obtained by using the fission track methods. In order to obtain complete data on the fissionable element internal contamination using animals, we started a similar study using Th as contaminating element and Wistar London breed rats as laboratory animals. Different ways to obtain internal contaminations were investigated: ingestion, inhalation, absorption by skin and through wounds. In this stage, Wistar-London breed rats of the same sex, weight and age were internal contaminated by 1 ml Th solution ingestion for each rat corresponding to an Annual Limit Intake.The animals were kept in normal life conditions and under permanent medical surveillance up to their sacrifice. Also, their evacuations where sampled every 24 hours. They were sacrificed at different time intervals after their contamination: 2 days (RAT 1), 7 days (RAT 2) and 14 days (RAT 3). After sacrifice, their vital organs were sampled, weighed, calcined, reweighed and finally analysed by track detection using the fission track micromapping technique. This technique was used in the following conditions: - mica-muscovite as track detector pre-etched for fossil tracks 18 h in HF; - the neutron irradiations were performed in the nuclear reactor VVR-S Bucharest at the neutron fluences of 3x10 15 - 2x10 16 fast neutrons/cm 2 . In order to check whether there is any U contribution to the fission track densities obtained in track detectors, U existing in the rat body due to food and water, the neutron irradiations of the ensembles were performed with and without 1 mm Cd shielding; - the visualization of the Th induced fission tracks were obtained by chemical etching in HF, 3 h at room temperature; - the Th track micromappings obtained in track detectors were studied by optical microscopy using a stereomicroscope WILD M7S for ensemble study (X6-X31) and a binocular ZEISS JENA microscope for qualitative and

  9. Development of nuclear microfilters using the fission tracks registration technique

    International Nuclear Information System (INIS)

    Yamasaki, I.M.; Geraldo, L.P.

    1990-10-01

    Nuclear microfilters with mean pores diameter in the range from 1.9 to 10.6 μm have been produced using the fission tracks registration technique in Makrofol KG (8 μm thickness). Fluctuations around 11% and 10% were obtained respectively for the pores size and pores uniformity in the analysis of a typical sample of microfilter. The essential features of the microfilters were similar to those ones, commercially known as Nuclepore and thus they may be routinely employed in the several applications areas of the Industry and Biology. (author)

  10. Electronics for very high rate tracking detectors

    International Nuclear Information System (INIS)

    Williams, H.H.; Dressnandt, N.; Ekenberg, T.; Gerds, E.J.; Newcomer, F.M.; Tedja, S.; Van Berg, R.; Van der Speigel, J.

    1995-01-01

    Results are presented on a system of electronics designed for very high rate tracking detectors at the SSC and LHC. The primary goal was a system for signal detection, time measurement, and readout for the straw tracker for SDC. An integrated circuit incorporating eight channels of amplifier-shaper-discriminator (including detector tail cancellation), and two different integrated circuits for time measurement are described. The performance of tracking measurements up to counting rates of 8 MHz per wire is reported, as well as preliminary results from a baseline restoration circuit. (orig.)

  11. Fission track dating and estimation of uranium in some garnets of Rajasthan (India)

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S; Virk, H S [Punjabi Univ., Patiala (India). Dept. of Physics

    1978-09-01

    The experimental procedure, involving the preparation, etching, thermal neutron irradiation and scanning of the garnet samples, is described. The calculated fission track ages and uranium concentration are tabulated.

  12. Registration of alpha particles in Makrofol-E nuclear track detectors

    Energy Technology Data Exchange (ETDEWEB)

    Rammah, Y.S. [Physics Department, Faculty of Science, Menoufia University, Shebin El-Koom (Egypt); Abdalla, Ayman M., E-mail: aymanabdalla62@hotmail.com [Physics Department, Faculty of Sciences and Arts, Najran University, P. O. Box. 11001, Najran (Saudi Arabia); Promising Centre for Sensors and Electronic Devices, Faculty of Arts and Sciences, Najran University (Saudi Arabia); Ashraf, O., E-mail: osama.ashraf@edu.asu.edu.eg [Physics Department, Faculty of Education, Ain Shams University, Cairo 11575 (Egypt); Ashry, A.H. [Physics Department, Faculty of Education, Ain Shams University, Cairo 11575 (Egypt)

    2016-06-15

    Highlights: • Makrofol-E detectors have been irradiated with alpha particles and fission fragments. • Fast detection of alpha particles in Makrofol-E detectors. • Bulk etching rate was calculated from fission track diameters. - Abstract: Fast detection of alpha particles in the range from 1 to 5 MeV in Makrofol-E polycarbonate nuclear track detectors (PCTDs) using a new chemical etchant was investigated. {sup 252}Cf and {sup 241}Am-thin open sources were used for irradiating Makrofol-E detectors with fission fragments and alpha particles in air at normal pressure and temperature (NPT). A chain of experimental work has been carried out using new etchants to register alpha particle in short time in Makrofol-E polycarbonate detectors. The etching efficiency were exhibited a clear dependence on the amount of methanol in the etching solution and etching time. The optimized chemical condition obtained at this stage of development for 200 μm Makrofol-E detectors are (8 ml of 10 N NaOH + 2 ml CH{sub 3}OH) etching solutions at 60 °C for 3 h. In this study; it is possible to observe energy detection windows for Makrofol-E detectors according to applied etching duration. Makrofol-E introduced the characteristic Bragg peak, which indicates the advantages of this detector as alpha spectrometer. Consequently, the suggested new etchant can be developed for heavy ions detection and monitoring radon levels and its daughters.

  13. Dating method by fission tracks: some Brazilian examples

    International Nuclear Information System (INIS)

    Fonseca, Ariadne do Carmo

    1996-01-01

    The Fission Track method (TF) complements the dating of a interval of tectonic events occurred in low temperatures not detected by another radiometric methods. In the South part of Craton of Sao Francisco the dating of apatites of archaean rocks produced ages TF between 900 and 500 Ma, reflecting the progressive acting of the Brazilian margin mobile belts in the archaean craton areas. Apatite of some igneous and metamorphic rocks of the Braziliana age, in the Faixa Ribeira segment, between the Rio de Janeiro and Salvador cities, produced TF ages between 140 and 80 Ma. The basaltic and alkaline volcanism related to the Atlantic Ocean opening dated from this interval. The TF dating in apatites of the continental margin rocks allowed to date the event. In the Cabo Frio region (Southeastern part of Rio de Janeiro State), titanite and apatite of the Transamazonic orthognaisses produced TF dates between 190 and 80 to 40 Ma. The age around 190 Ma date previously the rift formation precursor of the South Atlantic Ocean opening, while the ages between 80 and 40 Ma were related to the alkaline rocks intrusion. The examples mentioned demonstrate the event diversity which may be dated by the Fission Tracks method, mainly in the craton area and margin belts study

  14. Determination of the uranium concentration in water samples by the technique of fission track recording

    International Nuclear Information System (INIS)

    Geraldo, L.P.

    1979-01-01

    The technique of fission track register was developed for the determination of micrograms of uranium. The Makrofol KG, a synthetic plastic made by Bayer, was used as the detector and the wet method was utilized. The detector calibration curve allows the determination of the uranium concentration in a sample within an interval from 8.0 to 0.4μgU/L, the total error ranging from 3.3% to 29.0% respectively. The method was used in the determination of the uranium content in various water samples, obtained from various sources like rivers, sea etc. in the state of Sao Paulo, Brazil. Results were compared with those obtained by other authors using different methods. The average concentration found in sea waters (3.27 +- 9.12μgU/l) by this method is compatible with the international average accepted value of 3.3μgU/l, irrespective of site and depth. The determination of the uranium content by fission track counting has proved to be very convenient. (Author) [pt

  15. Amplifier channel for a fission fragment semiconductor detector

    International Nuclear Information System (INIS)

    Tyurin, G.P.

    1981-01-01

    To compensate the decrease of the transformation coefficient of fission fragment semiconductor detector (SCD) developed is a special amplification channel with controlled transfer coefficient. The block diagram of the channel is presented, the main functional units of which are as follows: preamplifying head with charge-sensitive and timing preamplifiers, linear amplifier and the circuit of spectrum position stabilization, which includes a differential discriminator, integrator and reference signal generator. The amplification channel is made in the CAMAC standard and has the following specifications: dinamical input capacitance of charge-sensitive amplifier c=10000 n PHI, signal amplitude at output of the linear amplifier at energy of fission fragments of 120 MeV has negative polarity and is equal to 5 V. Pulse amplitude change at SCD sensitivity decrease to 50% constitutes not more than 1%. Timing preamplifier has the gain factor at voltage of K=80 at front duration of 3.5 nc. Time resolution of the amplification channel is not worse than 1 nc. Dimensions of preamplifying head are 40x40x15 mm. The amplification channel permitted to use SCD for long-term measurements of fission fragment spectra [ru

  16. Scintillating fibre tracking neutron detector

    International Nuclear Information System (INIS)

    Karlsson, Joakim.

    1995-04-01

    A detector for measurements of collimated fluxes of neutrons in the energy range 2-20 MeV is proposed. It utilizes (n.p) elastic scattering in scintillating optical fibres placed in successive orthogonal layers perpendicular to the neutron flux. A test module has been designed, constructed and tested with respect to separation of neutron and gamma events. The pulse height measurements show the feasibility to discriminate between neutron, gamma and background events. Application to measurements of fusion neutrons is considered. 18 refs, 22 figs, 4 tabs

  17. The etching property of the surface of CR-39 and the track core radius of fission fragment

    CERN Document Server

    Mineyama, D; Yamauchi, T; Oda, K; El-Rahman, A

    2002-01-01

    The etch pits of fission fragments in CR-39 detector have been observed carefully using an atomic force microscope (AFM) after extremely short chemical etching in stirred 6N KOH solution kept at 70degC. It was found that there existed a thin layer where the bulk etch rate is relativity from large the etch-pit growth curve for the etching duration between 10 and 1800 seconds. The track core radius of fission fragment was evaluated to be about 6 nm from the extrapolation of the growth curve in a thinner region. (author)

  18. Mapping of uranium and thorium in radioactive rocks using nuclear track solid detectors

    International Nuclear Information System (INIS)

    Bouch, C.M.

    1982-01-01

    α-Autoradiography and studies of induced fission in a research nuclear reactor (IEA-R1, IPEN, Sao Paulo) were done, employing Solid-State Nuclear Track detectors, in order to study the distribution of α-emitters, U and Th in rocks. Polished sections of rocks were prepared and photographed. Etching conditions were studied in order to adapt the detectors to the studies of microdistribution and macrodistribution of tracks. Polycarbonate foils (Bayer, Makrofol) were chosen as fission-fragments detectors and the technique of fission induced with reactor neutrons to obtain the distribution of U and Th were studied. Uranium and thorium standards evaporated on the surface of the detectors, as well as thorite and uraninite grains, were irradiated in order to measure the integrated flux of neutrons, the effective cross sections for fission with reactor neutrons for 232 Th(0,05b) and 238 U(0,30b) and to study the contribution of 238 U fission in thorium mapping. A technique for determination of uranium and thorium in minerals was studied and applied to Mica, for which were determined the contents of 4,2 ppb U e 58 ppb Th. (Author) [pt

  19. Interaction of 80 MeV PI+ with different targets: Track detector studies

    Energy Technology Data Exchange (ETDEWEB)

    Tabassum, L; Chohan, A S [Government Coll., Lahore. (Pakistan) Deptt. of Physics Khan, H.A. (Pakistan Inst. of Nuclear Science and Technology, Islamabad (Pakistan). Nuclear Engineering Div.)

    1990-04-01

    CR-39 and mica track detectors have been used in the study of the interactions of 80 MeV PI+ with thin targets of Bi, Pb, Ho, Sb. The binary fission cross sections, the length and angular distributions of etched tracks have been obtained. The cross-section values obtained by using CR-39 are higher as compared to those obtained with mica. (author).

  20. Interaction of 80 MeV PI+ with different targets: Track detector studies

    International Nuclear Information System (INIS)

    Tabassum, L.; Chohan, A.S.

    1990-01-01

    CR-39 and mica track detectors have been used in the study of the interactions of 80 MeV PI+ with thin targets of Bi, Pb, Ho, Sb. The binary fission cross sections, the length and angular distributions of etched tracks have been obtained. The cross-section values obtained by using CR-39 are higher as compared to those obtained with mica. (author)

  1. Monopole track characteristics in plastic detectors

    Science.gov (United States)

    Ahlen, S. P.

    1975-01-01

    Total and restricted energy loss rates were calculated for magnetic monopoles of charge g = 137 e in Lexan polycarbonate. Range-energy curves are also presented. The restricted energy loss model is used to estimate the appearance of a monopole track in plastic detectors. These results should be useful for the design and analysis of monopole experiments.

  2. Properties of silver chloride track detectors

    International Nuclear Information System (INIS)

    Dmitriev, V.D.; Kocherov, N.P.; Novikova, N.R.; Perfilov, N.A.

    1976-01-01

    The experiments on preparation of silver chloride track detectors and their properties are described. The results of X-ray structural analysis and data on sensitivity to charged particles and actinic light of silver chloride crystals, doped with several elements, are presented. (orig.) [de

  3. Concentration of uranium in human cancerous tissues of Southern Iraqi patients using fission track analysis

    International Nuclear Information System (INIS)

    Al-Hamzawi, A.A.; Al-Qadisiyah University, Qadisiyah; Jaafar, M.S.; Tawfiq, N.F.

    2015-01-01

    The technique of nuclear fission track analysis with solid state nuclear track detectors CR-39 has been applied to determine concentrations of uranium in cancerous samples of human tissues that excised from patients in the three key southern Iraqi governorates namely, Basrah, Dhi-Qar, and Muthanna. These provinces were the sites of intensive military events during the Gulf Wars in 1991 and 2003. The investigation was based on the study of 24 abnormal samples and 12 normal samples for comparing the results. These samples include four types of soft tissues (kidney, breast, stomach and uterus). The results show that uranium concentrations in the normal tissues ranged between (1.42-4.76 μg kg -1 ), whereas in the cancerous tissues ranged between (3.37-7.22 μg kg -1 ). The uranium concentrations in the normal tissues were significantly lower than in the abnormal tissues (P < 0.001). (author)

  4. Determination of the uranium content in phosphate fertilizers by the fission track registration technique

    International Nuclear Information System (INIS)

    Rocha, A.C.S. da.

    1983-01-01

    The application of fission track registration technique (SSNTD) to determine the uranium contents in phosphate fertilizers is dealt with. Samples were prepared by the wet method and the detector used was Makrofol Kg 10μm thick. The determination of uranium in phosphate fertilizer industry is of considerable interest in environmental control. The roots of vegetables tend to absorb and accumulate uranium form soil and so the human body could be contaminated. The phosphate fertilizers were originated from the phosphate-rich apatite deposits located in the high naturally radioactive areas of Araxa and Tapira in the state of Minas Gerais, Brazil. The results obtained ranged from 11.1 to 100ppm of uranium with a total error from 8.2 to 15.7%. The thorium contributions to the total track counting were discounted, though the actual concentrations of thorium in the samples were not determined. (Author) [pt

  5. Irradiation effects in fused quartz 'Suprasil' as a detector of fission fragments under high flux of reactor neutrons

    International Nuclear Information System (INIS)

    Moraes, O.M.G. de.

    1984-01-01

    A systematic study about the registration characteristics of synthetic fused quartz 'Suprasil I' use as a detector of fission fragments under high flux of reactor neutrons and the effects of irradiation on it was performed. Fission fragments of 252 Cf, gamma radiation doses of of 60 Co up to 150 MGy, and integrated neutrons fluxes up to 10 20 n/cm 2 were used. A model to explain the effects on track registration and development characteristics of 'Suprasil I' irradiated on reactors were proposed, based on the obtained results for efficiency an for annealing. (C.G.C.) [pt

  6. On methodical problems in estimating geological temperature and time from measurements of fission tracks in apatite

    International Nuclear Information System (INIS)

    Jonckheere, R.

    2003-01-01

    The results of apatite fission-track modelling are only as accurate as the method, and depend on the assumption that the processes involved in the annealing of fossil tracks over geological times are the same as those responsible for the annealing of induced fission tracks in laboratory experiments. This has hitherto been assumed rather than demonstrated. The present critical discussion identifies a number of methodical problems from an examination of the available data on age standards, borehole samples and samples studied in the framework of geological investigations. These problems are related to low- ( 60 deg. C) annealing on a geological timescale and to the procedures used for calculating temperature-time paths from the fission-track data. It is concluded that it is not established that the relationship between track length and track density and the appearance of unetchable gaps, observed in laboratory annealing experiments on induced tracks, can be extrapolated to the annealing of fossil tracks on a geological timescale. This in turn casts doubt on the central principle of equivalent time. That such uncertainties still exist is in no small part due to an insufficient understanding of the formation, structure and properties of fission tracks at the atomic scale and to a lack of attention to the details of track revelation. The methodical implications of discrepancies between fission track results and the independent geological evidence are rarely considered. This presents a strong case for the re-involvement of track physicists in fundamental fission track research

  7. Tracking the NOvA Detectors' Performance

    Science.gov (United States)

    Psihas, Fernanda; NOvA Collaboration

    2016-03-01

    The NOvA experiment measures long baseline νμ -->νe oscillations in Fermilab's NuMI beam. We employ two detectors equipped with over 10 thousand sets of data-taking electronics; avalanche photo diodes and front end boards which collect and process the scintillation signal from particle interactions within the detectors. These sets of electronics -as well as the systems which power and cool them- must be monitored and maintained at precise working conditions to ensure maximal data-taking uptime, good data quality and a lasting life for our detectors. This poster describes the automated systems used on NOvA to simultaneously monitor our data quality, diagnose hardware issues, track our performance and coordinate maintenance for the detectors.

  8. Determination of palaeotemperatures of apatite with the fission-track method

    International Nuclear Information System (INIS)

    Bertagnolli, E.; Maerk, E.; Bertel, E.; Pahl, M.; Maerk, T.D.

    1981-01-01

    As a consequence of thermal fading of fission tracks in minerals, the fission-track dating method can be used to obtain a sensitive geothermometer for unfolding thermal events in the history of rocks, especially if it is possible to determine the temperature associated with a measured fission-track age, i.e., yielding a temperature age. Based on the concept of a minimum fission-track length the differential annealing equation has been solved for apatite, taking into account the fact that the annealing coefficient depends also on the degree of fission-track reduction. This allows us to calculate an improved age-temperature relationship for apatite, which gives for a measured corrected fission-track age the corresponding temperature, assuming either linear or exponential time-dependence of the temperature. The present results for apatite are compared with previous calculations in apatite and sphene. As expected, a fission-track age of apatite dates a younger (lower temperature) point in the thermal-cooling history than a fission-track age of sphene. (author)

  9. Dating by fission tracks in archaeology. 1. Principles and experimental methods

    International Nuclear Information System (INIS)

    Poupeau, G.; Zuleta, E.

    1984-01-01

    The principles of dating method by uranium fission tracks are shortly exposed. The conditions of application to the archaeology are discussed, in particular for the volcanic glasses, where the fossil fission tracks are often affected of a beginning of effacement. (L.C.) [pt

  10. Dating by fission track method: study of neutron dosimetry with natural uranium thin films

    International Nuclear Information System (INIS)

    Iunes, P.J.

    1990-06-01

    Fission track dating is described, focalizing the problem of the decay constant for spontaneous fission of 238 U and the use of neutron dosimetry in fission track analysis. Experimental procedures using thin films of natural uranium as neutron dosimeters and its results are presented. The author shows a intercomparison between different thin films and between the dosimetry with thin film and other dosimetries. (M.V.M.). 52 refs, 12 figs, 9 tabs

  11. Automatic counting of fission fragments tracks using the gas permeation technique

    CERN Document Server

    Yamazaki, I M

    1999-01-01

    An automatic counting system for fission tracks induced in a polycarbonate plastic Makrofol KG (10 mu m thickness) is described. The method is based on the gas transport mechanism proposed by Knudsen, where the gas permeability for a porous membrane is expected to be directly related to its track density. In this work, nitrogen permeabilities for several Makrofol films, with different fission track densities, have been measured using an adequate gas permeation system. The fission tracks were produced by irradiating Makrofol foils with a 252Cf calibrated source in a 2 pi geometry. A calibration curve fission track number versus nitrogen permeability has been obtained, for track densities higher than 1000/cm sup 2 , where the spark gap technique and the visual methods employing a microscope, are not appropriate for track counting.

  12. THE ATLAS INNER DETECTOR TRACK BASED ALIGNMENT

    CERN Document Server

    Marti i Garcia, Salvador; The ATLAS collaboration

    2018-01-01

    The alignment of the ATLAS Inner Detector is performed with a track-based alignment algorithm. Its goal is to provide an accurate description of the detector geometry such that track parameters are accurately determined and free from biases. Its software implementation is modular and configurable, with a clear separation of the alignment algorithm from the detector system specifics and the database handling. The alignment must cope with the rapid movements of the detector as well as with the slow drift of the different mechanical units. Prompt alignment constants are derived for every run at the calibration stage. These sets of constants are then dynamically split from the beginning of the run in many chunks, allowing to describe the tracker geometry as it evolves with time. The alignment of the Inner Detector is validated and improved by studying resonance decays (Z and J/psi to mu+mu-), as well as using information from the calorimeter system with the E/p method with electrons. A detailed study of these res...

  13. High tracking resolution detectors. Final Technical Report

    International Nuclear Information System (INIS)

    Vasile, Stefan; Li, Zheng

    2010-01-01

    High-resolution tracking detectors based on Active Pixel Sensor (APS) have been valuable tools in Nuclear Physics and High-Energy Physics research, and have contributed to major discoveries. Their integration time, radiation length and readout rate is a limiting factor for the planed luminosity upgrades in nuclear and high-energy physics collider-based experiments. The goal of this program was to demonstrate and develop high-gain, high-resolution tracking detector arrays with faster readout, and shorter radiation length than APS arrays. These arrays may operate as direct charged particle detectors or as readouts of high resolution scintillating fiber arrays. During this program, we developed in CMOS large, high-resolution pixel sensor arrays with integrated readout, and reset at pixel level. Their intrinsic gain, high immunity to surface and moisture damage, will allow operating these detectors with minimal packaging/passivation requirements and will result in radiation length superior to APS. In Phase I, we designed and fabricated arrays with calorimetric output capable of sub-pixel resolution and sub-microsecond readout rate. The technical effort was dedicated to detector and readout structure development, performance verification, as well as to radiation damage and damage annealing.

  14. The effects of radiation damage accumulation and annealing on fission-track dating of titanite

    International Nuclear Information System (INIS)

    Enkelmann, Eva; Jonckheere, Raymond; Ratschbacher, Lothar

    2005-01-01

    Fission-track dating of titanite is hindered by the fact that track etching is anisotropic in fresh titanites and becomes isotropic with increasing radiation damage. Independent age determinations with the population method are problematic due to different track counting efficiencies (Q) for ρ s in unannealed and ρ i in annealed titanite. Independent age determinations with the external detector method depend on correction factors for the track registration geometries (G = 0.5), counting efficiencies (Q) and range deficit (R = 1.38); however, Q is unaffected by annealing. It was attempted to determine GQR through calculation, direct experiment and on the basis of age standards. The direct experiment involves measurements of the ratio of the induced-track densities in titanite and a co-irradiated external detector. The track densities in the internal titanite surfaces could not be measured but the results for the external surfaces confirm that this approach leads to a significant overestimation of GQR, due to prior annealing. The GQR-values determined on the basis of age standards are consistent with that obtained by calculation assuming that Q ∼ 1, although there is no experimental confirmation for this fact apart from their isotropic etching characteristics. The fact that identical GQR-factors were obtained on standards of different age and uranium content suggests that a single GQR-value is appropriate for dating titanites within a broad range of radiation damage. In terms of the ζ-calibration this implies that a single ζ-factor is also suitable for dating different titanites. These findings suggest that other factors besides the accumulation of alpha-recoil damage, such as a phase transition, could be co-responsible for the different etching characteristics of annealed and unannealed titanites

  15. Absolute measurement of thermal neutron fluence and its application for fission track dating

    International Nuclear Information System (INIS)

    Ganzawa, Yoshihiro; Honda, Teruyuki; Nozaki, Tetsuya.

    1988-01-01

    The absolute measurements of thermal neutron fluence for fission track dating have been developed after the proceeding results of Honda et al. (1987). The 2,200 m/sec activation cross section of 197 Au (98.8 barn) is corrected to 87.4 barn (σa) by the three factors of the neutron temperature, Maxwellian distribution of thermal neutrons and non 1/v correction factor for the above absolute measurement. The calibrated factor (B th ) of standard glasses (SRM613, SRM962a, CN-1 and CN-2) and zeta-a (ζa) values for fission track dating are determined on the basis of these experimental results. The values of B th , (7.47 ± 0.29) x 10 9 for SRM613, (7.43 ± 0.34) x 10 9 for SRM962a, (2.50 ± 0.06) x 10 9 for CN-1 and (2.74 ± 0.06) x 10 9 for CN-2 closely agree with those reported previously by Honda et al. (1987). Further, the ζa values of 392.3 ± 16.5 for SRM962a and SRM613, 131.4 ± 3.1 for CN-1 and 144.1 ± 3.3 for CN-2 calculated from B th , effective thermal neutron fission cross-section σf (497.4 barn), isotopic abundance ratio 235 U/ 239 U, I (7.2527 x 10 -3 ) and spontaneous fission decay constant of 238 U, λ f (6.85 x 10 -17 a -7 ) show close agreement with ζ b values (392.5 ± 10.0, 131.6 ± 3.3, 140.1 ± 3.5) derived from the absolute age of Fish Canyon Tuff (27.9 ± 0.7 Ma) respectively. The fission track dating of zircons separated from Oligocene-Miocene tuff distributed in Eastern Hokkaido have been carried out by the external detector method using ζ a . The obtained ages are 28.6 ± 0.7 Ma (1 - 2) and 23.3 ± 0.7 Ma (3 - 2). These results agree well with the geologic age supported from Ashoro Fossil Fauna, K-Ar ages of volcanic rocks and stratigraphy in this area. (author)

  16. NEET Micro-Pocket Fission Detector. Final Project report

    Energy Technology Data Exchange (ETDEWEB)

    Unruh, T. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rempe, Joy [Idaho National Lab. (INL), Idaho Falls, ID (United States); McGregor, Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ugorowski, Philip [Idaho National Lab. (INL), Idaho Falls, ID (United States); Reichenberger, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ito, Takashi [Idaho National Lab. (INL), Idaho Falls, ID (United States); Villard, J. -F. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    A collaboration between the Idaho National Laboratory (INL), the Kansas State University (KSU), and the French Alternative Energies and Atomic Energy Commission, Commissariat à l'Énergie Atomique et aux Energies Alternatives, (CEA), is funded by the Nuclear Energy Enabling Technologies (NEET) program to develop and test Micro-Pocket Fission Detectors (MPFDs), which are compact fission chambers capable of simultaneously measuring thermal neutron flux, fast neutron flux and temperature within a single package. When deployed, these sensors will significantly advance flux detection capabilities for irradiation tests in US Material Test Reactors (MTRs). Ultimately, evaluations may lead to a more compact, more accurate, and longer lifetime flux sensor for critical mock-ups, and high performance reactors, allowing several Department of Energy Office of Nuclear Energy (DOE-NE) programs to obtain higher accuracy/higher resolution data from irradiation tests of candidate new fuels and materials. Specifically, deployment of MPFDs will address several challenges faced in irradiations performed at MTRs: Current fission chamber technologies do not offer the ability to measure fast flux, thermal flux and temperature within a single compact probe; MPFDs offer this option. MPFD construction is very different than current fission chamber construction; the use of high temperature materials allow MPFDs to be specifically tailored to survive harsh conditions encountered in-core of high performance MTRs. The higher accuracy, high fidelity data available from the compact MPFD will significantly enhance efforts to validate new high-fidelity reactor physics codes and new multi-scale, multi-physics codes. MPFDs can be built with variable sensitivities to survive the lifetime of an experiment or fuel assembly in some MTRs, allowing for more efficient and cost effective power monitoring. The small size of the MPFDs allows multiple sensors to be deployed, offering the potential to

  17. Naturally etched tracks in apatites and the correction of fission track dating

    CERN Document Server

    Tien, J L

    1999-01-01

    Naturally etched tracks have been found in apatites from the rapid cooled, high-level Kunon pluton in the Zhangzhou Igneous Complex, SE China. This is manifested by the fact that the apatite fission track (FT) age derived from conventional counting of spontaneous and induced tracks yields a result of 140.6+-6.5 Ma, which is much older than the ages determined using other methods on different minerals from the same rock. When tracks are observed after etching the polished inner sections of the apatite grains, the naturally etched tracks characterized by having hazy boundaries can be distinguished from the normal tracks with sharp boundaries. The age obtained by omitting these fading-resistant hazy tracks, 76.5+-4.0 Ma, indicates the time of the Kunon pluton cooling down to approx 100 deg. C. The corrected peak age (73.8 Ma) is consistent with the other apatite FT peak ages (79.2 to 70.2 Ma) of the nearly contemporaneous plutons in the same igneous complex.

  18. The spark counting of etched fission-fragment tracks in polycarbonate for a personal neutron dosimetry system

    International Nuclear Information System (INIS)

    Harrison, K.G.; Hancock, I.B.; Holt, P.D.; Wylie, J.W.

    1977-10-01

    A new type of personal neutron dosimeter, in which neutron-induced fissions in a thin 237 Np foil are detected by a polycarbonate track-detector, is under development at Harwell for use in a nuclear-fuel reprocessing plant. As part of the development programme, an experimental dosimeter, etching facility and spark counter have been used to study the spark-counting method for counting fission-fragment tracks in polycarbonate. Emphasis has been placed on developing operating procedures for the counter consistent with good overall reproducibility. Existing methods for the optimizing and testing of spark counters is briefly reviewed and a practical operational testing procedure is devised. The optimized system is found to be relatively foolproof in operation and gives good results in unskilled use as well as under carefully-controlled laboratory conditions. (author)

  19. Determination of the uranium concentration in apatite by the fission - track registration technique

    International Nuclear Information System (INIS)

    D'Oliveira Cardoso, D.

    1983-01-01

    The feasibility of using the fission-track registration technique to determine the uranium content in the phosphate rock beneficiation steps carried on by CompanhiA Arafertil, Araxa, Minas Gerais, Brazil is studied. This determination is of considerable interest to the environmental control of the Arafertil installations as well as of its surroundings or of the areas where these products will be used. The so called wet method was adopted and a 10 μm polycarbonate foil, fabricated by Bayer under the trade name Makrofol KG was used as detector. From the calibration curve obtained, it was possible to determine uranium contents in sample solutions ranging from 21 to 212 μg U/1 with an accuracy of 8 to 14.7%, respectively. The results obtained demonstrated that the technique used is appropriate to the purposes previously aimed at. (Author) [pt

  20. Trace uranium determination in beverages and mineral water using fission track techniques

    International Nuclear Information System (INIS)

    Cheng, Y.L.; Lin, J.Y.; Hao, X.H.

    1993-01-01

    The uranium contents of beverages and mineral water have been estimated using the technique of fission track analysis with polycarbonate detector. The U contents in beverages have been found to vary from 0.26 ± 0.03 to 1.65 ± 0.07 ppb, the average value is 0.93 ± 0.05 ppb. The mean U content in mineral water is 9.20 ± 0.16 ppb, which is ∼ 10 times higher than the mean U content of beverages. The present study shows the high U content in mineral water, indicating need for further investigation of U content in mineral water for the studies of radiation health hazards. (Author)

  1. Track fitting and resolution with digital detectors

    International Nuclear Information System (INIS)

    Duerdoth, I.

    1982-01-01

    The analysis of data from detectors which give digitised measurements, such as MWPCs, is considered. These measurements are necessarily correlated and it is shown that the uncertainty in the combination of N measurements may fall faster than the canonical 1/√N. A new method of track fitting is described which exploits the digital aspects and which takes the correlations into account. It divides the parameter space into cells and the centroid of a cell is taken as the best estimate. The method is shown to have some advantages over the standard least-squares analysis. If the least-squares method is used for digital detectors the goodness-of-fit may not be a reliable estimate of the accuracy. The cell method is particularly suitable for implementation on microcomputers which lack floating point and divide facilities. (orig.)

  2. Central Tracking Detector Based on Scintillating Fibres

    CERN Multimedia

    2002-01-01

    Scintillating fibres form a reasonable compromise for central tracking detectors in terms of price, resolution, response time, occupancy and heat production. \\\\ \\\\ New fluorescents with large Stokes shifts have been produced, capable of working without wavelength shifters. Coherent multibundles have been developed to achieve high packing fractions. Small segments of tracker shell have been assembled and beam tests have confirmed expectations on spatial resolution. An opto-electronic delay line has been designed to delay the track patterns and enable coincidences with a first level trigger. Replacement of the conventional phosphor screen anode with a Si pixel chip is achieved. This tube is called ISPA-tube and has already been operated in beam tests with a scintillating fibres tracker. \\\\ \\\\ The aim of the proposal is to improve hit densities for small diameter fibres by increasing the fraction of trapped light, by reducing absorption and reflection losses, by reflecting light at the free fibre end, and by inc...

  3. Track length estimation applied to point detectors

    International Nuclear Information System (INIS)

    Rief, H.; Dubi, A.; Elperin, T.

    1984-01-01

    The concept of the track length estimator is applied to the uncollided point flux estimator (UCF) leading to a new algorithm of calculating fluxes at a point. It consists essentially of a line integral of the UCF, and although its variance is unbounded, the convergence rate is that of a bounded variance estimator. In certain applications, involving detector points in the vicinity of collimated beam sources, it has a lower variance than the once-more-collided point flux estimator, and its application is more straightforward

  4. Monopole-track characteristics in plastic detectors

    Science.gov (United States)

    Ahlen, S. P.

    1976-01-01

    Total and restricted energy loss rates are calculated for magnetic monopoles of charge g = 137 e in Lexan polycarbonate. Range-energy curves are also presented. The restricted-energy-loss model is used to estimate the appearance of a monopole track in plastic detectors. The results are applied to the event observed by Price et al. and identified by them as a monopole. It is found that the observed etch rate is consistent with what one would expect for a slow magnetic monopole. These results should also be of use to other investigators for both the design and analysis of monopole experiments.

  5. Silicon detectors for tracking and vertexing

    International Nuclear Information System (INIS)

    Nomerotski, Andrei

    2009-01-01

    This review covers recent developments in silicon detectors used for particle physics experiments for the tracking and vertexing systems. After a general introduction the main focus of the report is on new challenges for this field posed by requirements of the future generation machines. Technologies reviewed in more detail are column parallel CCDs, DEPFET, vertical integration of sensors and electronics and several others which allow fast readout and low mass design. Important system issues such as mechanical arrangements for the sensors and power distribution, which are critical for the low mass design, are also discussed.

  6. CR-39 plastic nuclear track detector and its application in nuclear science

    International Nuclear Information System (INIS)

    Zhai Pengji; Tang Xiaowei; Wang Long; Liang Tianjiao

    2000-01-01

    The transparent and stable plastic material CR-39 can be used as a nuclear track detector which is highly sensitive to charged particles. It can record tracks induced by protons , alphas, fission fragments and other charged particles. Among various available solid state nuclear track detectors CR-39 has the lowest deposited energy density detection-threshold. The response of CR-39 to charged particles and the response curve of υ T of different charged particles to REL are given. The CR-39 detector is widely used in studies of nuclear reactions, angular distributions and reaction cross-sections caused by neutrons and charged particles. Neutron spectra, over a wide energy range, can be measured by the combination of CR-39 and a transformation screen. The successful applications of CR-39 in alpha particle dosimetry, environmental science (especially in the measurement of radon) and in biomedicine, such as the analysis of alpha radioactivity in sections of organic tissues, are described

  7. Nuclear Fragmentation Induced by Relativistic Projectiles Studied in the 4$\\pi$ Configuration of Plastic Track Detectors

    CERN Multimedia

    2002-01-01

    % EMU19 \\\\ \\\\ The collisions of heavy ions at relativistic energies have been studied to explore a number of questions related with hot and dense nuclear matter in order to extend our knowledge of nuclear equation-of-state. There are other aspects of these interactions which are studied to expound the process of projectile and/or target disintegrations. The disintegrations in question could be simply binary fissions or more complex processes leading to spallation or complete fragmentation. These important aspects of nuclear reactions are prone to investigations with nuclear track detectors. \\\\ \\\\One of the comparatively new track detector materials, CR-39, is sensitive enough to record particles of Z~$\\geq$~6 with almost 100\\% efficiency up to highly relativistic energies. The wide angle acceptance and exclusive measurements possible with plastic track detectors offer an opportunity to use them in a variety of situations in which high energy charged fragments are produced. The off-line nature of measuring tra...

  8. Studies on fission tracks and distributions of uranium and rare earths in granite materials

    International Nuclear Information System (INIS)

    Matsuda, Hiroshi; Sakanoue, Masanobu

    1987-01-01

    Many materials contain fossil records of the slow spontaneous fission of uranium they contain as an impurity. Fission fragments, heavy charged particles released in each fission event, produce microscopic trails of radiation damage that may persist over geological times and may be developed to a size observable under an optical microscope by a suitable etching treatment. Such tracks are also produced by fissions induced by thermal neutron irradiation of the uranium. When the material is heated sufficiently, it anneals and the the microscopic trails become shorter and narrower. The track density decreases, because the chemical etchant will not reach some of the shortened tracks. Measurements of track densities before and after annealing can be used, along with laboratory studies of annealing rates, to determine the annealing temperature. Also, the track density of induced fissions is related to the concentration of uranium and the fluence of neutrons to which it was exposed. If the track density due to induced fissions can be distinguished from that due to fossil tracks, estimates of either the concentration or the fluence can be made if the other is known. Two such materials (one a fragment of a granite paving stone, the other a piece of stained glass from a cathedral window) that had been exposed to the atomic bomb at Nagasaki were used in the present work. The fossil record in zircons in the granite was used to estimate the temperature to which it had been exposed in the bombing. Induced fissions were used to estimate the concentration of uranium in the zircons. Nonuniform heating and cooling and nearly uniform exposure to the neutrons make the granite sample unsuitable for determining the neutron fluence from the bomb. Induced fissions in the stained glass were used to estimate the concentration of uranium and the thermal neutron fluence from the A-bomb. Annealing of tracks in glass was also studied

  9. Etching of fission tracks in silicate glasses by means of deionized water

    International Nuclear Information System (INIS)

    Dran, J.C.; Petit, J.C.

    1985-09-01

    Fission tracks have been revealed in silicate glasses with deionized water. Their sharp conical shape implies a marked enhancement of the dissolution rate along their core and consequently a cone angle and an etching efficiency (close to 100%) much higher than previously reported for glasses. We show that etching of fission tracks in natural environments has generally very limited geochemical implications except in specific cases such as that found in the Oklo uranium ores

  10. Tracking and vertexing with the ATLAS detector at the LHC

    International Nuclear Information System (INIS)

    Hirsch, F.

    2011-01-01

    The Inner Detector of the ATLAS experiment at the Large Hadron Collider at CERN contains three tracking systems: The silicon Pixel Detector, the Silicon Microstrip Tracker and the Transition Radiation Tracker. In combination these detectors provide excellent track and vertex reconstruction efficiencies and resolutions. This paper describes studies which show the performance of track and vertex reconstruction on data collected at 7 TeV center-of-mass energy.

  11. Fission-track dating of apatite from deep borehole ATK-1 at Atikokan, Ontario

    International Nuclear Information System (INIS)

    Naeser, C.W.; Crowley, K.D.

    1990-01-01

    Fission-track age and lengths have been determined on apatite separated from core recovered from the ATK-1 deep borehole at Atikokan, Ontario. The apatite ages decrease down the borehole, from 515 ± 72 Ma at the top to 376 ± 46 Ma at a depth of 993 m. The mean confined track length for fossil fission tracks in the apatite is 12.4 μm. Within the limits of the measurement the track lengths are the same for all the samples. The results of this study indicate that the rocks found currently at the surface have never been heated above ∼100C since Upper Cambrian time

  12. Nuclear Track Detectors. Searches for Exotic Particles

    CERN Document Server

    Giacomelli, Giorgio

    2008-01-01

    We used Nuclear Track Detectors (NTD) CR39 and Makrofol for many purposes: i) Exposures at the SPS and at lower energy accelerator heavy ion beams for calibration purposes and for fragmentation studies. ii) Searches for GUT and Intermediate Mass Magnetic Monopoles (IMM), nuclearites, Q-balls and strangelets in the cosmic radiation. The MACRO experiment in the Gran Sasso underground lab, with ~1000 m^2 of CR39 detectors (plus scintillators and streamer tubes), established an upper limit for superheavy GUT poles at the level of 1.4x10^-16 cm^-2 s^-1 sr^-1 for 4x10^-5 detectors exposed for 4.22 y, gave an upper limit for IMMs of ~1.3x10^-15 cm^-2 s^-1 sr^-1. The experiments yielded interesting upper limits also on the fluxes of the other mentioned exotic particles. iii) Environmental studies, radiation monitoring, neutron dosimetry.

  13. A study of commercially-available polyethylene terephthalate (PET) and polycarbonate as nuclear track detector materials

    Science.gov (United States)

    Espinosa, G.; Golzarri, J. I.; Vazquez-Lopez, C.; Trejo, R.; Lopez, K.; Rickards, J.

    2014-07-01

    In the study of the sensitivity of materials to be used as nuclear track detectors, it was found that commercial polyethylene terephthalate (PET) from Ciel® water bottles, commercial roof cover polycarbonate, and recycled packaging strips (recycled PET), can be used as nuclear track detectors. These three commercial materials present nuclear tracks when bombarded by 2.27 MeV nitrogen ions produced in a Pelletron particle accelerator, and by fission fragments from a 252Cf source (79.4 and 103.8 MeV), after a chemical etching with a 6.25M KOH solution, or with a 6.25M KOH solution with 20% methanol, both solutions at 60±1°C. As an example, the nitrogen ions deposit approximately 1 keV/nm in the form of ionization and excitation at the surface of PET, as calculated using the SRIM code. The fission fragments deposit up to 9 keV/nm at the surface, in both cases generating sufficient free radicals to initiate the track formation process. However, 5 MeV alpha particles, typical of radon (222Rn) emissions, deposit only 0.12 keV/nm, do not present tracks after the chemical etching process. This valuable information could be very useful for further studies of new materials in nuclear track methodology.

  14. Apatite fission track dating and thermal history of Qing-He region in Altay Mountains

    International Nuclear Information System (INIS)

    Bao Zengkuan; Chinese Academy of Sciences, Beijing; Yuan Wanming; Dong Jinquan; Gao Shaokai

    2005-01-01

    Fission track ages (FTA) and track lengths of apatite from Qing-He diorite intrusion in Altay Mountains are measured. Apatite fission track ages of three diorite samples is range from (78±5) Ma to (95 ± 5) Ma, and the lengths of horizontal confined spontaneous fission tracks are (13.2 ± 1.2)-(13.5 ±1.3) μm. The distribution of the track length is narrow and symmetrical with a mean length of approximately 13.3 μm and a standard deviation of around 0.1 μm. The inverse modeling results show that thermal history of this region has four stages, two rapid uplift of this region still existed magmatic intrusion and tectonic movements in Yanshanian. (authors)

  15. Modifications in track registration response of PADC detector by energetic protons

    CERN Document Server

    Dwivedi, K K; Fink, D; Mishra, R; Tripathy, S P; Kulshreshtha, A; Khathing, D T

    1999-01-01

    It has been well established that different ionising radiations modify the track registration properties of dielectric solids. In an effort to study the response of Polyallyl diglycol carbonate (PADC Homalite) detector towards fission fragment, PADC detectors were exposed to 10 sup 4 Gy dose of 62 MeV protons and then one set of samples were exposed to fission fragments from a sup 2 sup 5 sup 2 Cf source. Two of these detectors were containing a thin layer of Buckminsterfullerene (C sub 6 sub 0). The study of the etched tracks by Leitz Optical Microscope reveals that the track diameters are enhanced by more than 70% in the proton irradiated zone as compared to that in the unirradiated zone. Scanning Electron Microscopy was performed after etching the sample in 6 N NaOH at 55 deg. C for different etching times, to study the details of the surface modifications due to proton irradiation of PADC detectors with and without C sub 6 sub 0 layer. Our observations revealed that the diameters and density of proton tra...

  16. Discovery Mondays - The detectors: tracking particles

    CERN Multimedia

    2005-01-01

    View of a module from the LHCb vertex detector, which will be presented at the next Discovery Monday. How do you observe the invisible? In order to deepen still further our knowledge of the infinitely small, physicists accelerate beams of particles and generate collisions between them at extraordinary energies. The collisions give birth to showers of new particles. What are they? In order to find out, physicists slip into the role of detectives thanks to the detectors. At the next Discovery Monday you will find out about the different methods used at CERN to detect particles. A cloud chamber will allow you to see the tracks of cosmic particles live. You will also be given the chance to see real modules for the ATLAS and for the LHCb experiments. Strange materials will be on hand, such as crystals that are heavier than iron and yet as transparent as glass... Come to the Microcosm and become a top detective yourself! This event will take place in French. Join us at the Microcosm (Reception Building 33, M...

  17. Fission track dating method: I. Study of neutron flux uniformity in some irradiation positions of IEA-R1 reactor

    International Nuclear Information System (INIS)

    Osorio, A.M.; Hadler, J.C.; Iunes, P.J.; Paulo, S.R. de

    1993-06-01

    In order to use the fission track dating method the flux gradient was verified within the sample holder, in some irradiation positions of the IEA-R1 reactor at IPEN/CNEN, Sao Paulo. The fission track dating method considers only the thermal neutron fission tracks, to subtract the other contributions sample irradiations with a cadmium cover was performed. The neutron flux cadmium influence was studied. (author)

  18. Detector independent cellular automaton algorithm for track reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Kisel, Ivan; Kulakov, Igor; Zyzak, Maksym [Goethe Univ. Frankfurt am Main (Germany); Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH (Germany); Collaboration: CBM-Collaboration

    2013-07-01

    Track reconstruction is one of the most challenging problems of data analysis in modern high energy physics (HEP) experiments, which have to process per second of the order of 10{sup 7} events with high track multiplicity and density, registered by detectors of different types and, in many cases, located in non-homogeneous magnetic field. Creation of reconstruction package common for all experiments is considered to be important in order to consolidate efforts. The cellular automaton (CA) track reconstruction approach has been used successfully in many HEP experiments. It is very simple, efficient, local and parallel. Meanwhile it is intrinsically independent of detector geometry and good candidate for common track reconstruction. The CA implementation for the CBM experiment has been generalized and applied to the ALICE ITS and STAR HFT detectors. Tests with simulated collisions have been performed. The track reconstruction efficiencies are at the level of 95% for majority of the signal tracks for all detectors.

  19. Improved fission neutron energy discrimination with {sup 4}He detectors through pulse filtering

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Ting, E-mail: ting.zhu@ufl.edu [University of Florida, Gainesville, FL (United States); Liang, Yinong; Rolison, Lucas; Barker, Cathleen; Lewis, Jason; Gokhale, Sasmit [University of Florida, Gainesville, FL (United States); Chandra, Rico [Arktis Radiation Detectors Ltd., Räffelstrasse 11, Zürich (Switzerland); Kiff, Scott [Sandia National Laboratories, CA (United States); Chung, Heejun [Korean Institute for Nuclear Nonproliferation and Control, 1534 Yuseong-daero, Yuseong-gu, Daejeon (Korea, Republic of); Ray, Heather; Baciak, James E.; Enqvist, Andreas; Jordan, Kelly A. [University of Florida, Gainesville, FL (United States)

    2017-03-11

    This paper presents experimental and computational techniques implemented for {sup 4}He gas scintillation detectors for induced fission neutron detection. Fission neutrons are produced when natural uranium samples are actively interrogated by 2.45 MeV deuterium-deuterium fusion reaction neutrons. Fission neutrons of energies greater than 2.45 MeV can be distinguished by their different scintillation pulse height spectra since {sup 4}He detectors retain incident fast neutron energy information. To enable the preferential detection of fast neutrons up to 10 MeV and suppress low-energy event counts, the detector photomultiplier gain is lowered and trigger threshold is increased. Pile-up and other unreliable events due to the interrogating neutron flux and background radiation are filtered out prior to the evaluation of pulse height spectra. With these problem-specific calibrations and data processing, the {sup 4}He detector's accuracy at discriminating fission neutrons up to 10 MeV is improved and verified with {sup 252}Cf spontaneous fission neutrons. Given the {sup 4}He detector's ability to differentiate fast neutron sources, this proof-of-concept active-interrogation measurement demonstrates the potential of special nuclear materials detection using a {sup 4}He fast neutron detection system.

  20. Fission track thermochronology : reconstructing the thermal and tectonic evolution of the crust

    International Nuclear Information System (INIS)

    Gleadow, A.J.W.

    1990-01-01

    The basis and current status of fission track analysis is reviewed showing the kinds of patterns of fission track parameters which result from a variety of thermal and tectonic histories. Fission track thermochronology is a well established method for reconstructing the thermal histories of rocks with particularly important applications in tectonic studies. Quantitative modelling of the thermal annealing of tracks in apatite shows that distinctive profiles of apparent fission track age can be related to a number of simple thermal history styles. The main types of profiles observed tend to be either an essentially linear decrease of apparent age with increasing depth, which relates to continuous uplift and denudation, or a concave-upwards profile produced by partial annealing in environments of tectonic stability or burial. More complex thermal histories produce compound profiles which are essentially just combinations of these two elements. Track length information allows the apparent age profiles to be interpreted in much greater detail. Examples of the major profile types have been identified in various geological environments and can be analysed to give information about, for example, uplift and denudation rates, the timing of uplift or low-grade thermal events and maximum palaeotemperatures experienced during burial. 25 refs., 8 figs

  1. Characterization of aerosols containing fissionable elements using solid-state track recorders

    International Nuclear Information System (INIS)

    Roberts, J.H.; Kafalenos, V.P.; Yule, T.J.

    1976-01-01

    An aerosol of U 3 O 3 highly enriched in 235 U was generated with a nebulizer from a suspension of U 3 O 8 powder in distilled water. The aerosol was collected on a membrane filter. Polycarbonate plastic, placed in good contact with the filter, was used to record fission tracks when the package was exposed to known fluences of slow neutrons. Fission-track stars associated with individual particles of U 3 O 8 were observed in the plastic. The fission-track distributions were converted to a particle size distribution for the aerosol. For a log normal distribution the geometric mean and standard deviation can be determined with better than 5% accuracy. This method can be applied to plutonium and other transuranic aerosols. (orig.) [de

  2. Future developments in etched track detectors for neutron dosimetry

    International Nuclear Information System (INIS)

    Tommasino, L.

    1987-01-01

    Many laboratories engaged in the field of personal neutron dosimetry are interested in developing better etching processes and improving the CR-39 detecting materials. To know how much effort must still be devoted to the development of etch track dosimetry, it is necessary to understand the advantages. limitations and degree of exploitation of the currently available techniques. So much has been learned about the chemical and electrochemical etching processes that an optimised combination of etching processes could make possible the elimination of many of the existing shortcomings. Limitations of etched track detectors for neutron dosimetry arise mainly because the registration occurs only on the detector surface. These damage type detectors are based on radiation induced chain scission processes in polymers, which result in hole-type tracks in solids. The converse approach, yet to be discovered, would be the development of cure-track detectors, where radiation induced cross linking between organic polymer chains could result in solid tracks in liquids. (author)

  3. Inner Detector Track Reconstruction and Alignment at the ATLAS Experiment

    CERN Document Server

    Danninger, Matthias; The ATLAS collaboration

    2017-01-01

    The Inner Detector of the ATLAS experiment at the LHC is responsible for reconstructing the trajectories of charged particles (‘tracks’) with high efficiency and accuracy. It consists of three subdetectors, each using a different technology to provide measurements points. An overview of the use of each of these subdetectors in track reconstruction, as well as the algorithmic approaches taken to the specific tasks of pattern recognition and track fitting, is given. The performance of the Inner Detector tracking will be summarised. Of crucial importance for optimal tracking performance is precise knowledge of the relative positions of the detector elements. ATLAS uses a sophisticated, highly granular software alignment procedure to determine and correct for the positions of the sensors, including time-dependent effects appearing within single data runs. This alignment procedure will be discussed in detail, and its effect on Inner Detector tracking for LHC Run 2 proton-proton collision data highlighted.

  4. Analysis for In-situ Fission Rate Measurements using 4He Gas Scintillation Detectors

    International Nuclear Information System (INIS)

    Lewis, Jason M.; Raetz, Dominik; Jordan, Kelly A.; Murer, David

    2013-06-01

    Active neutron interrogation is a powerful NDA technique that relies on detecting and analyzing fission neutrons produced in a fuel sample by an interrogating high neutron flux. 4 He scintillation gas fast neutron detectors are investigated in this paper for use in a novel fission rate measurement technique The He-4 detectors have excellent gamma rejection, a fast response time, and give significant information on incident neutron energy allowing for energy cuts to be applied to the detected signal. These features are shown in this work to allow for the detection of prompt fission neutrons in-situ during active neutron interrogation of a 238 U sample. The energy spectrum from three different neutrons sources ( 252 Cf, AmBe, AmLi) is measured using the 4 He detection system and analyzed. An initial response matrix for the detector is determined using these measurements and the kinematic interaction properties of the elastic scattering with the 4 He. (authors)

  5. The quantitative determination of uranium in human hair by fission track measurements

    International Nuclear Information System (INIS)

    Wilson, D.J.; Bentley, K.W.

    1985-01-01

    Human hairs containing a uranium burden were placed in contact with a mica sheet as the recording matrix and irradiated in a thermal neutron flux. The fission fragment tracks penetrating the mica were etched and counted. Calculations have been made to show the losses due to the fission fragment range being less than the diameter of the hair and for the variation of track density with distance from the line of contact between the hair and the mica. Experimental data from 50 μm diameter hair and those derived by calculation were compared. (author)

  6. Obsidian dating by fission track method; Datacao de obsidianas com o metodo dos tracos de fissao

    Energy Technology Data Exchange (ETDEWEB)

    Araya, A M.O.

    1990-12-01

    The fission track method was employed to obtain the age of twelve obsidian sample from Ecuador. By using the plateau-age correction method, we obtained the true age of each sample and were able to identify four groups of ages in the studied area. Thereafter we studied the fading of fission tracks in two obsidian samples with different origins: Yanaurcu, Ecuador and Monte Arci, Italy. We constructed Arrhenius plots and calculated activation energies for both samples. The results from thermal annealing experiments were compared with theoretical curves obtained by integrating an equation proposed by Shukolyukov et al (1965). (author). 43 refs, 20 figs, 10 tabs.

  7. A numerical model for the thermal history of rocks based on confined horizontal fission tracks

    DEFF Research Database (Denmark)

    Jensen, Peter Klint; Hansen, Kirsten; Kunzendorf, Helmar

    1992-01-01

    A numerical model for determination of the thermal history of rocks is presented. It is shown that the thermal history may be uniquely determined as a piece-by-piece linear function on the basis of etched confined, horizontal fission track length distributions, their surface densities, and the ur......A numerical model for determination of the thermal history of rocks is presented. It is shown that the thermal history may be uniquely determined as a piece-by-piece linear function on the basis of etched confined, horizontal fission track length distributions, their surface densities...

  8. Solid State Track Recorder fission rate measurements at high neutron fluence and high temperature

    International Nuclear Information System (INIS)

    Ruddy, F.H.; Roberts, J.H.; Gold, R.

    1985-01-01

    Solid State Track Recorder (SSTR) techniques have been used to measure 239-Pu, 235-U, and 237-Np fission rates for total neutron fluences approaching 5 x 10 17 n/cm 2 at temperatures in the range 680 to 830 0 F. Natural quartz crystal SSTRs were used to withstand the high temperature environment and ultra low-mass fissionable deposits of the three isotopes were required to yield scannable track densities at the high neutron fluences. The results of these high temperature, high neutron fluence measurements are reported

  9. Tracking of fission products release during refueling operations

    International Nuclear Information System (INIS)

    Agarwal, Sharad; Prajapat, M.K.; Vyas, Shyam; Hussain, S.A.

    2001-01-01

    It has been always observed that the release of fission products increase during refueling operations. At RAPP-3 and 4 an attempt has been made to follow-up the change in fission products activity release at each stage of refueling operation and quantification of concentrations of various radionuclides. This exercise was also extended to refueling operation of the channels containing suspected failed fuel. A level of FPNG ( 133 Xe) was observed to increase by a factor of about 10-40 during refueling of failed channel as compared to healthy channel. It can be concluded that by monitoring FPNG levels in exhaust status of the healthiness of spent fuel can be found out. This report discusses in detail the experiment conducted for this purpose. (author)

  10. Alignment of the ATLAS Inner Detector Tracking System

    CERN Document Server

    Lacuesta, V; The ATLAS collaboration

    2010-01-01

    ATLAS is a multipurpose experiment that records the LHC collisions. To reconstruct trajectories of charged particles produced in these collisions, ATLAS tracking system is equipped with silicon planar sensors and drift‐tube based detectors. They constitute the ATLAS Inner Detector. In order to achieve its scientific goals, the alignment of the ATLAS tracking system requires the determine accurately its almost 36000 degrees of freedom. Thus the demanded precision for the alignment of the silicon sensors is below 10 micrometers. This implies to use a large sample of high momentum and isolated charge particle tracks. The high level trigger selects those tracks online. Then the raw data with the hits information of the triggered tracks is stored in a calibration stream. Tracks from cosmic trigger during empty LHC bunches are also used as input for the alignment. The implementation of the track based alignment within the ATLAS software framework unifies different alignment approaches and allows the alignment of ...

  11. The thermal history of the Bowen Basin: a comparison of apatite fission track analysis and vitrinite reflectance

    International Nuclear Information System (INIS)

    Marshallsea, S.J.

    1987-01-01

    Vitrinite reflectance and apatite fission-track analysis (AFTA) are two techiques widely used to assess paleotemperatures of the order of 20-120 deg.C. in sedimentary basins. Whereas vitrinite reflectance is essentially a qualitative technique that gives an integrated measure of the entire thermal history, AFTA can reveal information on the variation of paleotemperatures through time because fission-tracks in apatite are continually produced throughout geological time. An apatite fission track study of the Upper Permian units of the Bowen Basin has offered the opportunity to compare the two paleotemperature indicators and place constraints on the timing of maximum paleotemperatures. The regional pattern of apatite fission-track ages closely coincides with the vitrinite reflectance indicating that maximum paleotemperatures have varied across the Basin with the central region of the Bowen Basin experiencing highest paleotemperatures. The reduction in apatite reflectance fission-track age with increasing reflectance represents the progressive annealing at temperatures around 60-120 deg. C. of those fission-tracks formed prior to the time of maximum temperatures. In those samples giving the youngest apatite fission-track ages all tacks were totally annealed at this time, and the fission-track age in these samples, in the range 90-120 Myr, indicate the time of cooling from the thermal maximum in the Early Cretaceous. 1 ref

  12. Studies on nitrogen mapping by various CR-39 track detectors

    Energy Technology Data Exchange (ETDEWEB)

    Somogyi, G.; Varga, Zs.; Hunyadi, I.; Freyer, K.; Treutler, H.Ch.

    1986-01-01

    The use of CR-39 track detectors for nitrogen distribution measurements via the /sup 14/N(n,p)/sup 14/C reaction is studied. The proton detection properties of different CR-39 products have been analyzed. The variation of background track density induced in the bulk of detectors is examined under different conditions of neutron irradiation. Analysis of our experimental data has led to the conclusion that the sources of proton background tracks are the fast neutron component of the neutron source, chlorine impurities in the detector and nitrogen diffused from the air into the upper layer of the detector. Efforts have been made to decrease the nitrogen content of diffusion origin by removing the upper detector layer and by outgassing the CR-39 sheet in vacuum before irradiation. Finally the ''signal/noise'' ratio for a steel specimen and the sensitivity of nitrogen determination are given.

  13. Fission track dating and thermal history of Habahe rock body in Altai

    International Nuclear Information System (INIS)

    Liu Shunsheng; Tan Kaixuan

    2002-01-01

    The fission track ages (FTA) of several apatite and zircon samples from Habahe rock body in Altai were determined. The FTA of apatites were 51.1-76.9 Ma, and FTA of zircons were 141-149 Ma. Modelling of the palaeo-temperature evolution [T(t)-path] of rock body relies on confined track length measurements and the annealing equations of Laslett et al. (1987). The thermal and uplift history of this region was discussed

  14. Antineutrino detector for anti ν oscillation studies at fission weapon tests and at LAMPF

    International Nuclear Information System (INIS)

    Kruse, H.W.; Loncoski, R.; Mack, J.

    1980-01-01

    Two anti ν oscillation experiments are planned, incorporating large volume (4200 l) liquid scintillation detectors 1) at large distances (450 to 800 m) from fission weapon tests and 2) at 12 to 50 m from LAMPF beam dump where significant anti ν/sub e/ events are detected only if some oscillation operates, such as ν/sub μ/ → ν/sub e/. Design criteria, detector characteristics, and experimental considerations are given

  15. Using New Fission Data with the Multi-detector Analysis System for Spent Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    A. V. Ramayya; A.V. Daniel (Joint Institute for Nuclear Research); C. J. Beyer (Vanderbilt Univ.); E. L. Reber; G. M. Ter-Akopian; G.S. Popeko; J. D. Cole; J. H. Hamilton; J. K. Jewell (INEEL); M. W. Drigert; R. Aryaeinejad; Ts.Yu. Oganessian

    1998-11-01

    New experiments using an array of high purity germanium detectors and fast liquid scintillation detectors has been performed to observe the radiation emitted from the induced fission of 235U with a beam of thermal neutrons. The experiment was performed at the Argonne National Laboratory Intense Pulsed Neutron Source. Preliminary observations of the data are presented. A nondestructive analysis system for the characterization of DOE spent nuclear fuel based on these new data is presented.

  16. Using New Fission Data with the Multi-detector Analysis System for Spent Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Jerald Donald

    1998-11-01

    New experiments using an array of high purity germanium detectors and fast liquid scintillation detectors has been performed to observe the radiation emitted from the induced fission of 235U with a beam of thermal neutrons. The experiment was performed at the Argonne National Laboratory Intense Pulsed Neutron Source. Preliminary observations of the data are presented. A nondestructive analysis system for the characterization of DOE spent nuclear fuel based on these new data is presented.

  17. Tracking Detectors in the STAR Experiment at RHIC

    Science.gov (United States)

    Wieman, Howard

    2015-04-01

    The STAR experiment at RHIC is designed to measure and identify the thousands of particles produced in 200 Gev/nucleon Au on Au collisions. This talk will focus on the design and construction of two of the main tracking detectors in the experiment, the TPC and the Heavy Flavor Tracker (HFT) pixel detector. The TPC is a solenoidal gas filled detector 4 meters in diameter and 4.2 meters long. It provides precise, continuous tracking and rate of energy loss in the gas (dE/dx) for particles at + - 1 units of pseudo rapidity. The tracking in a half Tesla magnetic field measures momentum and dE/dX provides particle ID. To detect short lived particles tracking close to the point of interaction is required. The HFT pixel detector is a two-layered, high resolution vertex detector located at a few centimeters radius from the collision point. It determines origins of the tracks to a few tens of microns for the purpose of extracting displaced vertices, allowing the identification of D mesons and other short-lived particles. The HFT pixel detector uses detector chips developed by the IPHC group at Strasbourg that are based on standard IC Complementary Metal-Oxide-Semiconductor (CMOS) technology. This is the first time that CMOS pixel chips have been incorporated in a collider application.

  18. A fission track technique used for hydrogeochemical prospecting in Northern India

    International Nuclear Information System (INIS)

    Singh, N.P.; Singh, S.; Virk, H.S.

    1988-01-01

    A fission track technique is employed to determine the uranium content of water samples collected from different locations of the middle and outer Himalayas. The regional threshold for the uranium content is determined for water samples of different areas. The identification of anomalies in an area of uranium mineralization confirmed that the hydrogeochemical technique could successfully be used for uranium exploration. (author)

  19. Estimation of U content in coffee samples by fission-track counting

    International Nuclear Information System (INIS)

    Sharma, P.K.; Lal, N.; Nagpaul, K.K.

    1985-01-01

    Because coffee is consumed in large quantities by humans, the authors undertook the study of the uranium content of coffee as a continuation of earlier work to estimate the U content of foodstuffs. Since literature on this subject is scarce, they decided to use the well-established fission-track-counting technique to determine the U content of coffee

  20. Fission track dating and uranium estimation in pegmatitic minerals of Rajasthan state (India)

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S; Virk, H S [Punjabi Univ., Patiala (India). Dept. of Physics

    1978-12-01

    Fission track geochronology of muscovite samples collected from some pegmatitic mines of Bhilwara and Ajmer districts of Rajasthan state (India) has been discussed. The ages obtained suggest the occurrence of Delhi Orogenic Cycle as the last major metamorphic activity in the region. The atomic fraction of uranium in muscovite samples is less than 1 p.p.b.

  1. Dating by fission tracks in archaeology. 2. Characterization and dating of obsidian artefact

    International Nuclear Information System (INIS)

    Poupeau, G.; Zuleta, E.

    1984-01-01

    The ways of obsidian characterization presently used in archaeology are presented. The possibilities of the fission track method are more specially discussed, with two examples of works done in Japan and on any samples of andine America. (L.C.) [pt

  2. Efficiency of a concentric matrix track detector surface scanning

    International Nuclear Information System (INIS)

    Bek-Uzarov, Dj.; Nikezic, D.; Kostic, D.; Krstic, D.; Cuknic, O.

    1995-01-01

    Heavy particle ionizing radiation track counting on the surface of a solid state round surface detector is made using the microscope and scanning step by step by a round field of vision. The whole solid state detector surface could not be fully or completely covered by round fields of visions. Therefore detector surface could be divided on the two parts, the larger surface, being under fields of vision, really scanned and no scanned missed or omitted surface. The ratio between omitted and scanned surfaces is so called track scanning efficiency. The knowledge of really counted, or scanned surface is a important value for evaluating the real surface track density an exposed solid state track detector. In the paper a matrix of a concentric field of vision made around the first microscope field of vision placed in center of the round disc of the scanned track detector is proposed. In a such scanning matrix the real scanned surface could be easy calculated and by the microscope scanning made as well. By this way scanned surface is very precisely obtained as well. Precise knowledge of scanned and omitted surface allows to obtain more precise scanning efficiency factor as well as real surface track density, the main parameter in solid state track detection measurements. (author)

  3. Study of ternary and quaternary spontaneous fission of 252Cf with the NESSI detector

    International Nuclear Information System (INIS)

    Tishchenko, V.G.; Jahnke, U.; Herbach, C.M.; Hilscher, D.

    2002-11-01

    Ternary and quaternary spontaneous decay of 252 Cf was studied with the NESSI detector, a combination of two 4π detectors for charged particles, neutrons and γ-rays. The applied method of particle identification by measuring the energies and relative time-of-flights of the decay products is shown to be very effective for the study of rare decay modes. The energy and angular distributions of the decay products, the associated neutron multiplicities, the total energy of the prompt γ-radiation as well as correlations between the various observables were measured for the first time in a single full-scale experiment. The characteristics of ternary fission known from previous investigations are confirmed in the frame of a methodically independent experiment. Preliminary estimates of the quaternary fission yield are presented. An attempt is made to determine the mechanism of quaternary fission. (orig.)

  4. Time-zero fission-fragment detector based on low-pressure multiwire proportional chambers

    CERN Document Server

    Assamagan, Ketevi A; Bayatyan, G L; Carlini, R; Danagulyan, S; Eden, T; Egiyan, K; Ent, R; Fenker, H; Gan, L; Gasparian, A; Grigoryan, N K; Greenwood, Z; Gueye, P; Hashimoto, O; Johnston, K; Keppel, C; Knyazyan, S; Majewski, S; Margaryan, A; Margaryan, Yu L; Marikian, G G; Martoff, J; Mkrtchyan, H G; Parlakyan, L; Sato, Y; Sawafta, R; Simicevic, N; Tadevosyan, V; Takahashi, T; Tang, L; Vartanian, G S; Vulcan, W; Wells, S; Wood, S

    1999-01-01

    A time-zero fission fragment (FF) detector, based on the technique of low-pressure multiwire proportional chambers (LPMWPC), has been designed and constructed for the heavy hypernuclear lifetime experiment (E95-002) at Thomas Jefferson National Accelerator Facility. Its characteristics and the method of time-zero reconstruction were investigated using fission fragments from a sup 2 sup 5 sup 2 Cf spontaneous fission source. The influence of the ionization energy loss was also studied. It is shown that Heptane, Hexane, and Isobutane gases at a pressure of 1-2 Torr are all suitable for such a FF detector. As desired by experiment, a timing resolution of about 200 ps (FWHM) for a chamber size of 21x21 cm sup 2 was achieved.

  5. Time-zero fission-fragment detector based on low-pressure multiwire proportional chambers

    International Nuclear Information System (INIS)

    Assamagan, K.; Baker, K.; Bayatyan, G.; Carlini, R.; Danagoulian, S.; Eden, T.; Egiyan, K.; Ent, R.; Fenker, H.; Gan, L.; Gasparian, A.; Grigoryan, N.; Greenwood, Z.; Gueye, P.; Hashimoto, O.; Johnston, K.; Keppel, C.; Knyazyan, S.; Majewski, S.; Margaryan, A.; Margaryan, Yu.; Marikyan, G.; Martoff, J.; Mkrtchyan, H.; Parlakyan, L.; Sato, Y.; Sawafta, R.; Simicevic, N.; Tadevosyan, V.; Takahashi, T.; Tang, L.; Vartanyan, G.; Vulcan, W.; Wells, S.; Wood, S.

    1999-01-01

    A time-zero fission fragment (FF) detector, based on the technique of low-pressure multiwire proportional chambers (LPMWPC), has been designed and constructed for the heavy hypernuclear lifetime experiment (E95-002) at Thomas Jefferson National Accelerator Facility. Its characteristics and the method of time-zero reconstruction were investigated using fission fragments from a 252 Cf spontaneous fission source. The influence of the ionization energy loss was also studied. It is shown that Heptane, Hexane, and Isobutane gases at a pressure of 1-2 Torr are all suitable for such a FF detector. As desired by experiment, a timing resolution of about 200 ps (FWHM) for a chamber size of 21x21 cm 2 was achieved

  6. The design and construction of the ZEUS central tracking detector

    Energy Technology Data Exchange (ETDEWEB)

    Foster, B.; Malos, J.; Saxon, D.H.; Clark, D.E.; Jamdagni, A.K.; Markou, C.; Miller, D.B.; Miller, D.G.; Toudup, L.W.; Auty, C.G.; Blair, G.A.; Brooks, C.B.; Cashmore, R.J.; Hanford, A.T.; Harnew, N.; Holmes, A.R.; Linford, W.; Martin, N.C.; McArthur, I.C.; Nash, J.; Nobbs, K.N.; Wastie, R.L.; Williams, M.T.; Wilson, F.F.; Wilson, R.D.; Hart, J.C.; Hatley, R.W.; Hiddleston, J.W.; Gibson, M.D.; McCubbin, N.A.; Middleton, A.; Morrissey, M.C.; Morrow, D.; O' Brien, P.; Payne, B.T.; Roberts, J.C.H.; Shaw, T.B.; Sinclair, C.K.; Wallis, E.W.G.; White, D.J.; Yeo, K.L.; Bullock, F.W.; Dumper, J.; Fraser, T.J.; Hayes, D.; Jones, T.W.; Strachan, D.E.; Vine, I.A. (H.H. Wills Physics Lab., Univ. of Bristol (United Kingdom) Dept. of Physics and Astronomy, Univ. of Glasgow (United Kingdom) Blackett Lab., Physics Dept., Imperial Coll., London (United Kingdom) Dept. of Physics, Nuclear Physics Lab., Univ. of Oxford (United Kingdom) Rutherford Appleton Lab., Chilton (United Kingdom) Dept. of Physics an

    1994-01-15

    The mechanical, electrical and electronic design and construction of the ZEUS central tracking detector are described, together with the chamber monitoring and environmental control. This cylindrical drift chamber is designed for track reconstruction, electron identification and fast event triggering in a high beam-crossing rate, high magnetic field application. (orig.)

  7. Rank Detector Preprocessor for Glint Reduction in a Tracking Radar

    CSIR Research Space (South Africa)

    Guest, IW

    1993-04-01

    Full Text Available A rank detector is used to defect instantaneous received power fades in tracking radar. On detection of a fade, censorship of the angular position measurement is implemented in a Kalman tracking filter. It is shown that this technique can typically...

  8. Secondary electrons detectors for beam tracking: micromegas and wire chamber

    International Nuclear Information System (INIS)

    Pancin, J; Chaminade, T; Drouart, A; Kebbiri, M; Riallot, M; Fernandez, B; Naqvi, F

    2009-01-01

    SPIRAL2 or FAIR will be able to deliver beams of radioactive isotopes of low energy (less than 10 MeV/n). The emittance of these new beams will impose the use of beam tracking detectors to reconstruct the exact impact position of the nuclei on the experimental target. However, due to their thickness, the classical detectors will generate a lot of energy and angular straggling. A possible alternative is the SED principle (Secondary Electron Detector). It consists of an emissive foil placed in beam and a detector for the secondary electrons ejected by the passing of the nuclei through the foil. An R and D program has been initiated at CEA Saclay to study the possibility to use low pressure gaseous detectors as SED for beam tracking. Some SED have been already used on the VAMOS spectrometer at GANIL since 2004. We have constructed new detectors on this model to measure their performances in time and spatial resolution, and counting rate. Other detector types are also under study. For the first time, a test with different micromegas detectors at 4 Torr has been realized. A comparison on the time resolution has been performed between wire chamber and micromegas at very low pressure. The use of micromegas could be promising to improve the counting rate capability and the robustness of beam tracking detectors.

  9. Fission-track evidence of tectonic evolution in the northwestern Qaidam Basin, China

    Science.gov (United States)

    Sun, Guo-Qiang; Liu, Wei-Ming; Guo, Jia-Jia; Wang, Ye-Tong

    2018-02-01

    Fission-track dating was conducted on zircons and apatites from 11 cores of the upper Xiaganchaigou Formation and lower Shangganchaigou Formation (northwestern Qaidam Basin). The obtained apatite fission-track age is 3.1-61.9 Ma, and the zircon fission-track age is 49.2-123.5 Ma. Although the average apatite age is consistent with ages predicted from the stratigraphy, nine of the 11 apatite fission-track ages have P(χ2) 5%, exhibiting consistent characteristics and indicating that zircons retain provenance age information after burial. From the zircon and apatite ages, the fission-track length distribution, and the geological setting, the northwestern Qaidam Basin has experienced two tectonothermal events since the Late Mesozoic, at 39.1 ± 9.3 to 133.7 ± 6.6 Ma and 1.2 ± 0.6 to 32.0 ± 3.0 Ma. The earlier (39.1-133.7 Ma) tectonothermal event resulted from the initial collision of the Indian and Eurasian plates. As a consequence of the collision, the Altyn Tagh fault, which forms the northwestern boundary of the Qaidam Basin, began to develop. Subsequently, uplift of the Altyn Tagh mountains began and the northwestern depression of the Qaidam Basin started to form. The later (1.2-32.0 Ma) tectonothermal event resulted from further collision of the Indian and Eurasian plates along the Yarlung Tsangpo suture zone. Strata in the Qaidam Basin were further deformed by transpression in this period and this period played a crucial role in petroleum accumulation.

  10. Single track coincidence measurements of fluorescent and plastic nuclear track detectors in therapeutic carbon beams

    International Nuclear Information System (INIS)

    Osinga, J-M; Jäkel, O; Ambrožová, I; Brabcová, K Pachnerová; Davídková, M; Akselrod, M S; Greilich, S

    2014-01-01

    In this paper we present a method for single track coincidence measurements using two different track detector materials. We employed plastic and fluorescent nuclear track detectors (PNTDs and FNTDs) in the entrance channel of a monoenergetic carbon ion beam covering the therapeutic energy range from 80 to 425 MeV/u. About 99% of all primary particle tracks detected by both detectors were successfully matched, while 1% of the particles were only detected by the FNTDs because of their superior spatial resolution. We conclude that both PNTDs and FNTDs are suitable for clinical carbon beam dosimetry with a detection efficiency of at least 98.82% and 99.83% respectively, if irradiations are performed with low fluence in the entrance channel of the ion beam. The investigated method can be adapted to other nuclear track detectors and offers the possibility to characterize new track detector materials against well-known detectors. Further, by combining two detectors with a restricted working range in the presented way a hybrid-detector system can be created with an extended and optimized working range

  11. A note on frequency distributions of fission tracks in apatite

    International Nuclear Information System (INIS)

    He, Z.; Lerche, I.

    1989-01-01

    Two different formulae, both purportedly describing track length reduction in apatite, are converted to forms useful in prediction of track length distributions along sedimentary burial history paths. Using the formalism, track length distribution data from four NW Canning Basin wells are inverted to determine the physical (chemical) parameters associated with the models as well as the heat flux variation with time. For each formula the resulting physical parameters are consistent among the wells tested but differ from laboratory-derived parameter values, and the thermal histories are consistent with those inferred from geological data. Comparison of the two models shows no evidence that one model should be favored over the other based on the data available. It is also shown that the resolution of the parameters is dependent not only on the quantity of the data but also on the ''quality'' -explicitly upon the variation and distribution with depth. (author)

  12. Earthquake prediction research with plastic nuclear track detectors

    International Nuclear Information System (INIS)

    Woith, H.; Enge, W.; Beaujean, R.; Oschlies, K.

    1988-01-01

    Since 1984 a German-Turkish project on earthquake prediction research has been operating at the North Anatolian fault zone in Turkey. Among many other parameters changes in Radon emission have also been investigated. Plastic nuclear track detectors (Kodak cellulose nitrate LR 115) are used to record alpha-particles emitted from Radon and Thoron atoms and their daughter isotopes. The detectors are replaced and analyzed every 3 weeks. Thus a quasi-continuous time sequence of the Radon soil gas emission is recorded. We present a comparison between measurements made with electronic counters and plastic track detectors. (author)

  13. The Siegen automatic measuring system for track detectors: new developments

    International Nuclear Information System (INIS)

    Rusch, G.; Winkel, E.; Noll, A.; Heinrich, W.

    1991-01-01

    Starting twelve years ago we have developed completely automatic scanning and measuring systems for nuclear track detectors. The hardware and software of these systems have continuously been improved. They were used in different heavy ion and cosmic ray experiments. In this paper we describe methods for high resolution REL measurements in plastic nuclear track detectors and methods to scan and measure nuclear disintegration stars in AgCl detectors using an automatic measuring technique. The system uses a stepping motor driven microscope stage, a video camera and an image analysis computer based on a MC68020 microprocessor. (author)

  14. The track finding algorithm of the Belle II vertex detectors

    Directory of Open Access Journals (Sweden)

    Bilka Tadeas

    2017-01-01

    Full Text Available The Belle II experiment is a high energy multi purpose particle detector operated at the asymmetric e+e− - collider SuperKEKB in Tsukuba (Japan. In this work we describe the algorithm performing the pattern recognition for inner tracking detector which consists of two layers of pixel detectors and four layers of double sided silicon strip detectors arranged around the interaction region. The track finding algorithm will be used both during the High Level Trigger on-line track reconstruction and during the off-line full reconstruction. It must provide good efficiency down to momenta as low as 50 MeV/c where material effects are sizeable even in an extremely thin detector as the VXD. In addition it has to be able to cope with the high occupancy of the Belle II detectors due to the background. The underlying concept of the track finding algorithm, as well as details of the implementation are outlined. The algorithm is proven to run with good performance on simulated ϒ(4S → BB̄ events with an efficiency for reconstructing tracks of above 90% over a wide range of momentum.

  15. Energy deposition measurements in fast reactor safety experiments with fission thermocouple detectors

    International Nuclear Information System (INIS)

    Wright, S.A.; Scott, H.L.

    1979-01-01

    The investigation of phenomena occurring in in-pile fast reactor safety experiments requires an accurate measurement of the time dependent energy depositions within the fissile material. At Sandia Laboratories thin-film fission thermocouples are being developed for this purpose. These detectors have high temperature capabilities (400 to 500 0 C), are sodium compatible, and have milli-second time response. A significant advantage of these detectors for use as energy deposition monitors is that they produce an output voltage which is directly dependent on the temperature of a small chip of fissile material within the detectors. However, heat losses within the detector make it necessary to correct the response of the detector to determine the energy deposition. A method of correcting the detector response which uses an inverse convolution procedure has been developed and successfully tested with experimental data obtained in the Sandia Pulse Reactor (SPR-II) and in the Annular Core Research Reactor

  16. Application of fission track technique for estimation of uranium concentration in drinking waters of Punjab

    International Nuclear Information System (INIS)

    Prabhu, S.P.; Raj, Sanu S.; Sawant, P.D.; Kumar, Ajay; Sarkar, P.K.; Tripathi, R.M.

    2010-01-01

    Full text: Drinking water samples were collected from four different districts, namely Bhatinda, Mansa, Faridkot and Firozpur, of Punjab for ascertaining the U(nat.) concentrations. The samples were collected from bore wells, hand pumps, tube wells and treated municipal water supply. All these samples (235 nos.) collected were preserved and processed by following the international standard protocol and analyzed by Laser Fluorimetry. Results of analysis by laser fluorimetry have been already reported. To ensure accuracy of the data obtained by laser fluorimetry, few samples (10 nos) from each district were analyzed by alpha spectrometry as well as by fission track analysis (FTA) technique. FTA in solution media for uranium has been already standardized in Bioassay laboratory of Health Physics Division. Few of drinking water sample was directly transferred to polythene tube sealed at one end. Lexan detector with proper identification mark was immersed in the samples and the other open end of the tube was also heat-sealed. Two tubes containing samples and one containing uranium standard (80 ppb) were irradiated in the Pneumatic Carrier Facility (PCF) of DHRUVA reactor. The Lexan detectors were then chemically etched and tracks were counted under an optical microscope at 400X magnification. Concentration of uranium in sample was determined by comparison technique. Quality assurance was carried out by replicate analysis and by analysis of standard reference materials. Uranium concentration in these samples ranged from 3.2 to 60.5 ppb with an average of 28.8 ppb. A t-test analysis for paired data was done to compare the results obtained by FTA and those obtained by laser fluorimeter. The calculated value for t is -1.19, which is greater than the tabulated value of t for 40 observations (-2.02 at 95% confidence level). This shows that the results of the measurements carried out by the FTA and laser fluorimetry are not significantly different. The preliminary studies

  17. Alignment of the ATLAS Inner Detector Tracking System

    CERN Document Server

    Heller, C; The ATLAS collaboration

    2011-01-01

    ATLAS is one of the multipurpose experiments that records the products of the LHC proton-proton and heavy ion collisions. In order to reconstruct trajectories of charged particles produced in these collisions, ATLAS is equipped with a tracking system built using two different technologies, silicon planar sensors (pixel and microstrips) and drift-tube based detectors. Together they constitute the ATLAS Inner Detector, which is embedded in a 2 T axial field. Efficiently reconstructing tracks from charged particles traversing the detector, and precisely measure their momenta is of crucial importance for physics analyses. In order to achieve its scientific goals, an alignment of the ATLAS Inner Detector is required to accurately determine its more than 700,000 degrees of freedom. The goal of the alignment is set such that the limited knowledge of the sensor locations should not deteriorate the resolution of track parameters by more than 20% with respect to the intrinsic tracker resolution. The implementation of t...

  18. Fission track astrology of three Apollo 14 gas-rich breccias

    Science.gov (United States)

    Graf, H.; Shirck, J.; Sun, S.; Walker, R.

    1973-01-01

    The three Apollo 14 breccias 14301, 14313, and 14318 all show fission xenon due to the decay of Pu-244. To investigate possible in situ production of the fission gas, an analysis was made of the U-distribution in these three breccias. The major amount of the U lies in glass clasts and in matrix material and no more than 25% occurs in distinct high-U minerals. The U-distribution of each breccia is discussed in detail. Whitlockite grains in breccias 14301 and 14318 found with the U-mapping were etched and analyzed for fission tracks. The excess track densities are much smaller than indicated by the Xe-excess. Because of a preirradiation history documented by very high track densities in feldspar grains, however, it is impossible to attribute the excess tracks to the decay of Pu-244. A modified track method has been developed for measuring average U-concentrations in samples containing a heterogeneous distribution of U in the form of small high-U minerals. The method is briefly discussed, and results for the rocks 14301, 14313, 14318, 68815, 15595, and the soil 64421 are given.

  19. Uranium fission track length distribution modelling for retracing chronothermometrical history of minerals

    International Nuclear Information System (INIS)

    Rebetez, M.

    1987-01-01

    Spontaneous fission of uranium 238 isotope contained in certain minerals creates damage zones called latent tracks, that can be etched chemically. The observation of these etched tracks and the measurement of their characteristics using an optical microscope are the basis of several applications in the domain of the earth sciences. First, the determination of their densities permits dating a mineral and establishing uranium mapping of rocks. Second, the measurement of their lengths can be a good source of information for retracing the thermal and tectonic history of the sample. The study of the partial annealing of tracks in apatite appears to be the ideal indicator for the evaluation of petroleum potential of a sedimentary basin. To allow the development of this application, it is necessary to devise a theoretical model of track length distributions. The model which is proposed takes into account the most realistic hypotheses concerning registration, etching and observation of tracks. The characteristics of surface tracks (projected lengths, depths, inclination angles, real lengths) and confined tracks (Track IN Track and Track IN Cleavage) are calculated. Surface tracks and confined tracks are perfectly complementary for chrono-thermometric interpretation of complex geological histories. The method is applied to the case of two samples with different tectonic history, issued from the cretaceous alcalin magmatism from the Pyrenees (Bilbao, Spain). A graphic method of distribution deconvolution is proposed. Finally, the uranium migration, depending on the hydrothermal alteration, is studied on the granite from Auriat (France) [fr

  20. Nuclear track detector kit for use in teaching

    International Nuclear Information System (INIS)

    Medveczky, L.; Somogyi, G.

    1986-01-01

    By the use of solid state nuclear track detectors (SSNTDs) one may carry out several useful and impressive educational experiments and demonstrations to illustrate different phenomena when teaching of nuclear physics. Realizing this situation the authors have published, since 1970, reports on several experiments for teaching demonstrations. Based on the authors instructions, a factory in Hungary (TANFRT, National Manufacturers and Suppliers of School Equipment, Budapest) constructed a kit for the use of nuclear track detectors in teaching. The portable kit contains the following items: alpha-emitting weak sources, solid state nuclear track detectors (unirradiated, irradiated, unetched and etched sheets), simple tools for carrying out experiments (facilities for irradiation and etching, etc.), slides showing photos of typical etch-tracks of light and heavy nuclei, user manual. By the help of the kit both pupils and teachers can perform various useful experiments and/or demonstrations. (author)

  1. Nuclear track detector kit for use in teaching

    Energy Technology Data Exchange (ETDEWEB)

    Medveczky, L.; Somogyi, G.; Nagy, M.

    1986-01-01

    By the use of solid state nuclear track detectors (SSNTDs) one may carry out several useful and impressive educational experiments and demonstrations to illustrate different phenomena when teaching of nuclear physics. Realizing this situation the authors have published, since 1970, reports on several experiments for teaching demonstrations. Based on the authors instructions, a factory in Hungary (TANFRT, National Manufacturers and Suppliers of School Equipment, Budapest) constructed a kit for the use of nuclear track detectors in teaching. The portable kit contains the following items: alpha-emitting weak sources, solid state nuclear track detectors (unirradiated, irradiated, unetched and etched sheets), simple tools for carrying out experiments (facilities for irradiation and etching, etc.), slides showing photos of typical etch-tracks of light and heavy nuclei, user manual. By the help of the kit both pupils and teachers can perform various useful experiments and/or demonstrations.

  2. Technique of neutron-induced (fission-track) autoradiography with histological detail

    International Nuclear Information System (INIS)

    Smith, J.M.; Taylor, G.N.; Jee, W.S.S.

    1980-01-01

    The primary advantage of neutron-induced or fission-track autoradiography compared with conventional autoradiography is that for low concentrations of fissile nuclides prohibitively long exposure times may be avoided. However, it is difficult to produce imaging of biological structures on the neutron-induced autoradiograph which would allow localization of the nuclide histologically. The technique presented circumvents this difficulty using a thin polycarbonate film applied to the histologically stained tissue section mounted on a quartz substrate. After irradiation of the tissue section with an appropriate thermal neutron flux, the fission fragment tracks are revealed by etching the film with KOH. The tracks, superimposed on the stained tissue, may be observed under the light microscope in the same manner as for conventional nuclear emulsion autoradiography

  3. Experimental examination of ternary fission in nuclear track emulsion

    Czech Academy of Sciences Publication Activity Database

    Mamatkulov, K. Z.; Ambrožová, Iva; Artemenkov, D. A.; Bradnova, V.; Firu, E.; Haiduc, M.; Kákona, Martin; Kattabekov, R. R.; Marey, A.; Neagu, A.; Ploc, Ondřej; Rusakova, V. V.; Stanoeva, R.; Turek, Karel; Zaitsev, A. A.; Zarubin, P. I.; Zarubina, I. G.

    2017-01-01

    Roč. 48, č. 6 (2017), s. 910-913 ISSN 1063-7796 Institutional support: RVO:61389005 Keywords : angular correlation * nuclear track emulsion Subject RIV: BF - Elementary Particles and High Energy Physics OBOR OECD: Particles and field physics Impact factor: 0.681, year: 2016

  4. Robust track fitting in the Belle II inner tracking detector

    International Nuclear Information System (INIS)

    Nadler, Moritz; Frühwirth, Rudolf

    2012-01-01

    Track fitting in the new inner tracker of the Belle II experiment uses the GENFIT package. In the latter both a standard Kalman filter and a robust extension, the deterministic annealing filter (DAF), are implemented. This contribution presents the results of a simulation experiment which examines the performance of the DAF in the inner tracker, in terms of outlier detection ability and of the impact of different kinds of background on the quality of the fitted tracks.

  5. Measurement of uranium in human teeth and kidney stones with the fission track technique

    International Nuclear Information System (INIS)

    Vartanian, R.

    1986-01-01

    The measurement of uranium in human teeth and in kidney stones was carried out using the fission track activation technique. In this determination 2759 and 2205 absolute counts of tracks for teeth samples and 1689 tracks for kidney stone samples were performed, respectively. The results are as follows: xsub(tooth) (1)=(0.227+-0.006) ppm, xsub(tooth) (2)=(0.143+-0.007) ppm and xsub(kidney)=(0.568+-0.020) ppm. The experimental method is described and the results are discussed. (author)

  6. Timing characteristics of a two-dimensional multi-wire cathode strip detector for fission fragments

    International Nuclear Information System (INIS)

    Vind, R.P.; Joshi, B.N.; Jangale, R.V.; Inkar, A.L.; Prajapati, G.K.; John, B.V.; Biswas, D.C.

    2014-01-01

    In the recent past, a gas filled two-dimensional multi-wire cathode strip detector (MCSD) was developed for the detection of fission fragments (FFs). The position resolution was found to be about 1.0 and 1.5 mm in X and Y directions respectively. The detector has three electrode planes consisting of cathode strip (X-plane), anode wires and split-cathode wires (Y-plane). Each thin wire of the anode plane placed between the two cathode planes is essentially independent and behaves like a proportional counter. The construction of the detector in detail has been given in our earlier paper. The position information has been obtained by employing high impedance discrete delay line read out method for extracting position information in X and Y-directions. In this work, the timing characteristics of MCSD detector are reported to explore the possible use of this detector for the measurement of the mass of the fission fragments produced in heavy ion induced fission reactions

  7. In-reactor testing of self-powered neutron detectors and miniature fission chambers

    International Nuclear Information System (INIS)

    Duchene, J.; LeMeur, R.; Verdant, R.

    1975-01-01

    The CEA has tested a variety of ''slow'' self-powered neutron detectors with rhodium, silver and vanadium emitters. Currently there are 120 vanadium detectors in the EL4 heavy water reactor. In addition, ''fast'' detectors with cobalt emitters have been tested at Saclay and 50 of these are in reactor. Other studies are concerned with 6 mm diameter miniature fission chambers. Two fast response chambers with argon-nitrogen filling gas became slow during irradiation, but operated to 600 deg C. An argon filled chamber of 4.7 mm diameter, for traversing in core system in pressurized water reactor, has shown satisfactory test results. (author)

  8. Effect of high gamma background on neutron sensitivity of fission detectors

    International Nuclear Information System (INIS)

    Balagi, V.; Prasad, K.R.; Kataria, S.K.

    2004-01-01

    Tests were performed on two parallel plate and two cylindrical fission detectors in pulse and dc mode. The effect of gamma background on neutron sensitivity was studied in thermal neutron flux from 30 nv to 60 nv over which gamma field intensity ranging from 230 kR/h to 3.7 MR/h was superposed. In the case of one of the parallel plate detectors the fall in neutron sensitivity was observed to be 3.7% at 1 MR/h and negligible below 1 MR/h. In the case of one of the cylindrical counters the fall in neutron sensitivity was negligible below 500 kR/h and 37% at 1 MR/h. The data was used to derive the design parameters for a wide range fission detector to be procured for PFBR instrumentation for operation at 600 degC and gamma background of 1 MR/h. (author)

  9. Observations of fission-tracks in zircons by atomic force microscope

    International Nuclear Information System (INIS)

    Ohishi, Shinnosuke; Hasebe, Noriko

    2012-01-01

    The fission-track (FT) method is a dating technique based on the observation of damage (tracks) by spontaneous fission of 238 U left in a mineral. The date is calculated from the track density and the uranium concentration in the mineral. This is possible because the number of tracks is a function of uranium concentration and time since the start of track accumulation. Usually, the number of tracks is counted under an optical microscope after etching (chemical expansion of a track). However, as FT density per unit area rises, it becomes difficult to count the number of tracks. This is due to the fact that FTs overlap one another and are unable to be readily distinguished. This research examines the potential of atomic force microscope (AFM) for FT dating using zircons, which are likely to show higher FT density than other minerals due to their high U concentrations. To obtain an AFM image for a sample prepared for FT dating, removing the static electricity of the sample is essential to avoid an unexpected movement of the cantilever. A grain should be wider than about 30 μm to bring the cantilever on the mineral surface. Polishing with a fine grained compound is very important. There is not much difference in sharpness between images by AC mode (scanning with vibrating cantilever at a constant cycle) and Contact mode (scanning with the cantilever always in close contact with the surface). To confirm how tracks can be identified with the AFM, an AFM image was compared with an image obtained with the optical microscope. When change in the number of tracks and their shapes were observed through stepwise etching, the track expanded as the etching time increased. In addition, the etching rate was slower for large tracks than those for small tracks. This implied that the AFM can be used to observe etching of zircons with different degrees of nuclear fission damage. A track that could not be seen with the optical microscope due to insufficient etching could be observed by

  10. Determination of nuclear tracks parameters on sequentially etched PADC detectors

    Science.gov (United States)

    Horwacik, Tomasz; Bilski, Pawel; Koerner, Christine; Facius, Rainer; Berger, Thomas; Nowak, Tomasz; Reitz, Guenther; Olko, Pawel

    Polyallyl Diglycol Carbonate (PADC) detectors find many applications in radiation protection. One of them is the cosmic radiation dosimetry, where PADC detectors measure the linear energy transfer (LET) spectra of charged particles (from protons to heavy ions), supplementing TLD detectors in the role of passive dosemeter. Calibration exposures to ions of known LET are required to establish a relation between parameters of track observed on the detector and LET of particle creating this track. PADC TASTRAK nuclear track detectors were exposed to 12 C and 56 Fe ions of LET in H2 O between 10 and 544 keV/µm. The exposures took place at the Heavy Ion Medical Accelerator (HIMAC) in Chiba, Japan in the frame of the HIMAC research project "Space Radiation Dosimetry-Ground Based Verification of the MATROSHKA Facility" (20P-240). Detectors were etched in water solution of NaOH with three different temperatures and for various etching times to observe the appearance of etched tracks, the evolution of their parameters and the stability of the etching process. The applied etching times (and the solution's concentrations and temperatures) were: 48, 72, 96, 120 hours (6.25 N NaOH, 50 O C), 20, 40, 60, 80 hours (6.25 N NaOH, 60 O C) and 8, 12, 16, 20 hours (7N NaOH, 70 O C). The analysis of the detectors involved planimetric (2D) measurements of tracks' entrance ellipses and mechanical measurements of bulk layer thickness. Further track parameters, like angle of incidence, track length and etch rate ratio were then calculated. For certain tracks, results of planimetric measurements and calculations were also compared with results of optical track profile (3D) measurements, where not only the track's entrance ellipse but also the location of the track's tip could be directly measured. All these measurements have been performed with the 2D/3D measurement system at DLR. The collected data allow to create sets of V(LET in H2 O) calibration curves suitable for short, intermediate and

  11. A computer program TRACK_P for studying proton tracks in PADC detectors

    Directory of Open Access Journals (Sweden)

    D. Nikezic

    2016-01-01

    Full Text Available A computer program for studying proton tracks in solid state nuclear track detectors was developed and described in this paper. The program was written in Fortran 90, with an additional tool for visualizing the track appearance as seen under the optical microscope in the transmission mode, which was written in the Python programming language. Measurable track parameters were determined and displayed in the application window and written in a data file. Three-dimensional representation of tracks was enabled. Examples of calculated tracks were also given in the present paper.

  12. Fission signal detection using helium-4 gas fast neutron scintillation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, J. M., E-mail: lewisj@ufl.edu; Kelley, R. P.; Jordan, K. A. [Nuclear Engineering Program, University of Florida, Gainesville, Florida 32611 (United States); Murer, D. [Arktis Radiation Detectors Ltd., 8045 Zurich (Switzerland)

    2014-07-07

    We demonstrate the unambiguous detection of the fission neutron signal produced in natural uranium during active neutron interrogation using a deuterium-deuterium fusion neutron generator and a high pressure {sup 4}He gas fast neutron scintillation detector. The energy deposition by individual neutrons is quantified, and energy discrimination is used to differentiate the induced fission neutrons from the mono-energetic interrogation neutrons. The detector can discriminate between different incident neutron energies using pulse height discrimination of the slow scintillation component of the elastic scattering interaction between a neutron and the {sup 4}He atom. Energy histograms resulting from this data show the buildup of a detected fission neutron signal at higher energies. The detector is shown here to detect a unique fission neutron signal from a natural uranium sample during active interrogation with a (d, d) neutron generator. This signal path has a direct application to the detection of shielded nuclear material in cargo and air containers. It allows for continuous interrogation and detection while greatly minimizing the potential for false alarms.

  13. Fission track dating: methodology and thermo-chronological applications in alpine and continental margin contexts

    International Nuclear Information System (INIS)

    Sabil, N.

    1995-06-01

    The fission track dating method has proved to be unique in thermo-chronology by its capability to describe the final phases of the cooling history and denudation of metamorphic massifs, like the thermal history of sedimentary formations or the dating of some volcanic materials. In this work we describe this method and present a series of new analytic techniques and calibrations which we realised in the aim of further use in geology. We discuss a few examples of such applications. In the french Occidental Alps, the analysis of fission track on apatite samples from the granites of the Sept Laux (Belledonne massif), in the Eau d' Olle valley, suggests that this method could bring a contribution to the actual discussion about the origin of some alpine valleys. The fission track method suggests that the opening of this valley could be the consequence of an active faulting from the middle Miocene until the present. The characterization of fluvial deposits through their detrital apatites fission tracks record could eventually be used to study river captures related to changes tectonic regimes. Therefore we studied the apatites of a paleo-delta located in the Isere middle valley at the sub-alpine 'sillon' level, and of two valleys, those of the Arc and of the Breda, located up the delta. The distribution of the fission track ages of those mineraIs has not confirmed a previously suggested model, which proposed that the studied paleo-delta could be associated with a paleo-Arc rather than a paleo-Breda. In the Moroccan Occidental Meseta, three granitic massifs located in the Rehamna have been selected for a thermo-chronological study. The analysis of the fission track in zircons and apatites of these granites recorded the thermo-tectonic events which have affected the Meseta ever since the opening of the Central Atlantic Ocean some 200 Ma ago. We show how a numerical simulation model recently (1994) proposed for the analysis of fission track in apatites allows us to specify

  14. Contribution of the fission-track method to the study of the Alpine chains: relationship between tectonics and metamorphism

    International Nuclear Information System (INIS)

    Carpena, J.

    1984-01-01

    The fission-track method allows geologists to date rocks and to get information on the thermal history of rocks. Fission tracks in minerals are essentially due to the spontaneous fission of uranium 238. The knowledge of the density of tracks and the concentration of uranium 238 lead to the determination of the age of the rock. The irradiation in a neutron flux of a sample of the rock allows the determination of the concentration of uranium. The age obtained is in fact an apparent age that does not take into account possible geological annealing process that may erase fission tracks, some corrections are then necessary. The first part of this work details the fission-track method, its scope and limitations. It is shown that fission-track method on apatites can reveal the thermal evolution of the rock and that the same method used on zircons can give information of the setting of volcanic rocks. The second part is dedicated to the contribution of the fission-track method to a both dating and thermal evolution study of a french-italian part of the Alpine chain

  15. Tracking detectors for the sLHC, the LHC upgrade

    CERN Document Server

    Sadrozinski, Hartmut F W

    2005-01-01

    The plans for an upgrade of the Large Hadron Collider (LHC) to the Super-LHC (sLHC) are reviewed with special consideration of the environment for the inner tracking system. A straw-man detector upgrade for ATLAS is presented, which is motivated by the varying radiation levels as a function of radius, and choices for detector geometries and technologies are proposed, based on the environmental constraints. A few promising technologies for detectors are discussed, both for sensors and for the associated front-end electronics. On-going research in silicon detectors and in ASIC technologies will be crucial for the success of the upgrade.

  16. Determination of the uranium concentration in samples of raw, retorted and spent shale from Irati, Parana-Brazil, by the fission track registration technique

    International Nuclear Information System (INIS)

    Cabral, R.G.

    1981-02-01

    The feasibility of the determination of uranium in oil shale, by the fission track registration technique is studied. The wet and dry methods were employed, using a Bayer policarbonate, Makrofol KG, as detector. It was created a new variant of the dry method. The fission track registration technique was used in samples of raw, retorted and spent shale from Irati, Parana in Brazil, 16 μg U/g, 20 μg U/g and 20μg U/g were found, respectively, with a total error ranging from 19% to 20%. Some experimental results were included for illustration and comparison. The feasibility of the determination of uranium in oil shale from Irati was verified. (Author) [pt

  17. Application of solid state nuclear track detectors in radiation protection

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Subba Ramu, M.C.; Mishra, U.C.

    1989-01-01

    This article reviews the current status of the application of nuclear track detectors with emphasis on recent developments in the field of radiation protection. Track etch detectors have been used for the measurements of low level radiation in the environment, fast neutron and radon daughter inhalation dose. Recent developments in the field of dosimetry seem to be promising. In fast neutron dosimetry, track etch detectors can be used without inclusion of fissile materials by using the electrochemical etching technique. These detectors can provide important information in the energy range upto 250 keV. Survey of this range of energy with TLD is difficult because they are extremely energy dependent and over-respond to low energy neutrons. Measurement of radon using track detectors can help to lower the cost of the radon dosimeters. Certain detectors are sensitive to alpha particles from radon and their progeny. Higher sensitivity permits their use in a passive type of personnel dosimeter, which does not require the troublesome aspects of air sampling for the collection of radon daughter samples. (author), 38 refs., 8 tabs., 12 figs

  18. Uranium content of coal ashes from Southern Brazil coal fueled power stations, by the fission track registration technique

    International Nuclear Information System (INIS)

    Morales, R.K.

    1981-01-01

    The feasibility of the application of the fission track registration technique for the determination of uranium in coal ashes was shown. The wet method was employed using as detector the Makrofol KG=10 μm, manufactured by Bayer. The coal ashes were originated from coal-fueled power stations localized in Southern Brazil. The results obtained ranged from 10 to 27 mg U/kg. Since the total error variation was from 18,4% to 23,8%, the method used was considered excellent. The determination of the uranium content in coal ashes is of considerable interest in environmental control in power stations, in their vicinity and wherever these ashes are used or stored. The technique used is the work proved to be very appropriate for the purpose aimed at. (Author) [pt

  19. Determination Of Uranium Concentration In Teeth Female Samples Using Fission Tracks In CR-39 From Different Countries

    International Nuclear Information System (INIS)

    Hummadi, S.S

    2010-01-01

    The present study was under taken to measure the uranium concentration in female teeth samples collected from different nationalities.The determination of uranium concentration in these samples has been done by using CR-39 track detector.The nuclear reaction is used as a source of nuclear fission fragments is (n, f) obtained by the bombardment of U-235 with thermal neutrons with flux (5*10 3 n/cm 2 .s) was used from (Am-Be) neutron source.The obtained results show the concentration is ranging from (0.58±0.7ppm) in Oman and Uae to (0.35±0.03ppm)in Iraqi for male, the uranium concentration was the highest in Oman and Uae for female

  20. Low-level radon measurements by nuclear track detectors

    International Nuclear Information System (INIS)

    Koksal, E. M.; Goksel, S. A.; Alkan, H.

    1985-01-01

    In the work to be described here we have developed a passive nuclear track dosimeter to measure the integrated value of indoor radon (Rn-222) over a long period of time. Passive radon dosimeter which we have developed in our laboratories makes use of two small pieces of CR-39 plastic (Allyl diglycol carbonate) as detectors for registering tracks of alpha particles emitted by radon. These CR-39 plastic detectors are fixed on the inside bottom of a cup-shaped polystrene enclosure which is closed at the top by a tissue permeable for gases only. CR-39 detectors exposed to radon gas in the indoor air for a period of six months then are removed and chemically etched to make the alpha particle tracks visible under the microscope. The counts of tracks are evaluated to determine the radon concentration in the air in comparison with the number of tracks produced by a known concentration of radon gas. By using the passive dosimeters developed and the chemical etching procedure descriped here, measurements of indoor radon concentrations were carried out in 45 houses in different districts of the city of Istanbul. In this pilot experiment mean radon concentrations between 0.7 and 3.5 pCi/l have been found in these houses. In order to improve the counting of alpha tracks produced on the detectors a prototype electrochemical etching system in addition to chemical etching, is being developed. (author)

  1. On the frequency distributions per unit area of the projected and etchable lengths of surface-intersecting fission tracks: influences of track revelation, observation and measurement

    International Nuclear Information System (INIS)

    Jonckheere, R.; Haute, P. van den

    1999-01-01

    In addition to the statistical bounds discussed, thermal history analysis based on the projected and etchable length distributions of surface intersecting fission tracks is limited by systematic factors related to track revelation, observation and measurement. The effects of track revelation, in particular, distort these distributions in the length intervals of interest. An observation threshold poses a problem if it is described by a critical angle θ c , but not if it is described by other criteria proposed in the literature. Measurement imprecisions, predictably, blur the thermal history information contained in these distributions. Measurements of semi-confined tracks, added as a result of surface etching, are a more promising alternative to confined track length measurements for accessing the thermal history record in the fission track length distribution. On the other hand, measurements of the projected lengths of surface intersecting tracks offer the theoretical possibility of determining the true volumetric density N and true mean length m of an arbitrary population of fission tracks, thus allowing direct determination of the corrected age of samples with complex thermal histories. On a methodical level, knowledge of N and m allows to determine the efficiency with which fission tracks are counted under the optical microscope under exactly the same conditions as those under which fission track counts for routine dating purposes are performed

  2. Irradiation positions for fission-track dating in the University of Pavia TRIGA Mark II nuclear reactor

    International Nuclear Information System (INIS)

    Oddone, Massimo; Meloni, Sandro; Balestrieri, Maria Laura; Bigazzi, Giulio

    2002-01-01

    An irradiation position arranged is described in the present paper for fission-track dating in the Triga Mark II reactor of the University of Pavia. Fluence values determined using the NIST glass standard SRM 962a for fission-track dating and the traditional metal foils are compared. Relatively good neutron thermalization (φ th /φ f = 0.956) and lack of significant fluence spatial gradients are good factors for fission-track dating. Finally, international age standards (or putative age standards) irradiated in this new position yielded results consistent with independent reference ages. (author)

  3. U and Th thin film neutron dosimetry for fission-track dating: application to the age standard Moldavite

    International Nuclear Information System (INIS)

    Iunes, P.J.; Bigazzi, G.; Hadler Neto, J.C.; Laurenzi, M.A.; Balestrieri, M.L.; Norelli, P.; Osorio Araya, A.M.; Guedes, S.; Tello S, C.A.; Paulo, S.R.; Moreira, P.A.F.P.; Palissari, R.; Curvo, E.A.C.

    2005-01-01

    Neutron dosimetry based on U and Th thin films was used for fission-track dating of the age standard Moldavite, the central European tektite, from the Middle Miocene deposit of Jankov (southern Bohemia, Czech Republic). Our fission-track age (13.98+/-0.58Ma) agrees with a recent 40 Ar/ 39 Ar age, 14.34+/-0.04Ma, based on several determinations on Moldavites from different sediments, including the Jankov deposit. This result indicates that the U and Th thin film neutron dosimetry represents a reliable alternative for an absolute approach in fission-track dating

  4. A numerical model for the thermal history of rocks based on confined horizontal fission tracks

    International Nuclear Information System (INIS)

    Jensen, P.K.; Kunzendorf, Helmar; Hansen, Kirsten

    1992-01-01

    A numerical model for determination of the thermal history of rocks is presented. It is shown that the thermal history may be uniquely determined as a piece-by-piece linear function on the basis of etched confined, horizontal fission track length distributions, their surface densities, and the uranium content. The initial track length distribution is taken into account. A relation between the measured track length distribution and age is given which includes correction for partial annealing. The annealing model used is the fanning Arrhenius plot. It is shown that track length distributions measured in transmitted light are biased favouring short tracks compared with measurements in reflected light. Testing of the model is performed on apatites from a tuffaceous sandstone from Bornholm (Denmark) yielding an estimate of the thermal history for the period of about 280 Ma back in time. (author)

  5. Liquid nitrogen enhancement of partially annealed fission tracks in glass; and reply

    International Nuclear Information System (INIS)

    Wagner, G.A.; Carpenter, B.S.; Pilione, L.J.; Gold, D.P.

    1977-01-01

    Pilione and Gold (Nature 262: 773 (1976)) stated that it was possible to reveal partially annealed fission tracks in glass by immersion in liquid N 2 , and that it was possible to increase the total number of etchable tracks by increasing the immersion time. The present authors attempted to duplicate the work of the former authors using the same glass. They found no significant change in the number of etchable tracks after immersion in liquid N 2 , and they concluded that the latter has no effect on annealed tracks in glass. Any observed enhancement of partially annealed tracks is probably a surface effect and has no effect on the interior matrix of the glass. A reply by Pilione and Gold is appended. (U.K.)

  6. Mechanism of track formation by charged particles in inorganic and organic solid-state track detectors

    International Nuclear Information System (INIS)

    Doerschel, B.; Pretzsch, G.; Streubel, G.

    1979-01-01

    Knowledge of the individual phases of track formation mechanism is necessary in some applications of solid-state track detectors. The generation of latent tracks is described by energy transfer processes of the charged particles along their paths using several different models. Etchability of the latent tracks is discussed on the basis of some distinct criteria taking into account different fractions of energy release by the primary and secondary particles during track generation. If these etchability criteria for latent tracks are fulfilled, visual particle tracks can be produced by a chemical etching process. Etch pit formation depends on the etching conditions. The geometrical parameters of the etching pits are given on the basis of known etching rates. Evaluation of individual particle tracks or determination of track density yields results depending on both the properties of the particles and the etching conditions. Determination of particle energy and particle fluence is discussed as an example. (author)

  7. 4D tracking with ultra-fast silicon detectors

    Science.gov (United States)

    F-W Sadrozinski, Hartmut; Seiden, Abraham; Cartiglia, Nicolò

    2018-02-01

    The evolution of particle detectors has always pushed the technological limit in order to provide enabling technologies to researchers in all fields of science. One archetypal example is the evolution of silicon detectors, from a system with a few channels 30 years ago, to the tens of millions of independent pixels currently used to track charged particles in all major particle physics experiments. Nowadays, silicon detectors are ubiquitous not only in research laboratories but in almost every high-tech apparatus, from portable phones to hospitals. In this contribution, we present a new direction in the evolution of silicon detectors for charge particle tracking, namely the inclusion of very accurate timing information. This enhancement of the present silicon detector paradigm is enabled by the inclusion of controlled low gain in the detector response, therefore increasing the detector output signal sufficiently to make timing measurement possible. After providing a short overview of the advantage of this new technology, we present the necessary conditions that need to be met for both sensor and readout electronics in order to achieve 4D tracking. In the last section, we present the experimental results, demonstrating the validity of our research path.

  8. LENMODEL: A forward model for calculating length distributions and fission-track ages in apatite

    Science.gov (United States)

    Crowley, Kevin D.

    1993-05-01

    The program LENMODEL is a forward model for annealing of fission tracks in apatite. It provides estimates of the track-length distribution, fission-track age, and areal track density for any user-supplied thermal history. The program approximates the thermal history, in which temperature is represented as a continuous function of time, by a series of isothermal steps of various durations. Equations describing the production of tracks as a function of time and annealing of tracks as a function of time and temperature are solved for each step. The step calculations are summed to obtain estimates for the entire thermal history. Computational efficiency is maximized by performing the step calculations backwards in model time. The program incorporates an intuitive and easy-to-use graphical interface. Thermal history is input to the program using a mouse. Model options are specified by selecting context-sensitive commands from a bar menu. The program allows for considerable selection of equations and parameters used in the calculations. The program was written for PC-compatible computers running DOS TM 3.0 and above (and Windows TM 3.0 or above) with VGA or SVGA graphics and a Microsoft TM-compatible mouse. Single copies of a runtime version of the program are available from the author by written request as explained in the last section of this paper.

  9. Proposal for a semiconductor high resolution tracking detector

    International Nuclear Information System (INIS)

    Rehak, P.

    1983-01-01

    A 'new' concept for detection and tracking of charged particles in high energy physics experiments is proposed. It combines a well known high purity semiconductor diode detector (HPSDD) with a heterojunction structure (HJ) and a negative electron affinity (NEA) surface. The detector should be capable of providing a two dimensional view (few cm 2 ) of multi-track events with the following properties: a) position resolution down to a few μm (10 8 position elements); b) high density of information (10 2 -10 3 dots per mm of minimum ionizing track); c) high rate capabilities (few MHz); d) live operation with options to be triggered and/or the information from the detector can be used as an input for the decision to record an event. (orig.)

  10. Feasibility studies for a wireless 60 GHz tracking detector readout

    CERN Document Server

    Dittmeier, Sebastian; Soltveit, Hans Kristian; Wiedner, Dirk

    2016-01-01

    The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the in...

  11. Response of cellulose nitrate track detectors to electron doses

    CERN Document Server

    Segovia, N; Moreno, A; Vazquez-Polo, G; Santamaría, T; Aranda, P; Hernández, A

    1999-01-01

    In order to study alternative dose determination methods, the bulk etching velocity and the latent track annealing of LR 115 track detectors was studied during electron irradiation runs from a Pelletron accelerator. For this purpose alpha irradiated and blank detectors were exposed to increasing electron doses from 10.5 to 317.5 kGy. After the irradiation with electrons the detectors were etched under routine conditions, except for the etching time, that was varied for each electron dose in order to reach a fixed residual thickness. The variation of the bulk etching velocity as a function of each one of the electron doses supplied, was interpolated in order to obtain dosimetric response curves. The observed annealing effect on the latent tracks is discussed as a function of the total electron doses supplied and the temperature.

  12. Computational response study of personal and albedo neutron dosemeters composed of solid state track detectors based on (n,α) reaction

    International Nuclear Information System (INIS)

    Palfalvi, J.

    1984-03-01

    The combined effect of incident and albedo neutrons on the response of several fission and (n,α) track detectors was investigated by calculations for monoenergetic neutrons and for neutrons from different energetic sources. The response functions are presented in tables and plots. (author)

  13. Study of a Tracking/Preshower Detector for the LHC

    CERN Multimedia

    2002-01-01

    % RD-2 Study of a Tracking/Preshower Detector for the LHC \\\\ \\\\An important goal in the design of a detector to operate with high machine luminosity at the LHC is the detection of electrons at either the trigger or analysis level as a signature of rare physics processes. The purpose of this R~\\&~D activity is the study of track-stub/preshower techniques in electron identification. Activities include the study of radiation tolerance for silicon pad counters of the preshower detector, with the associated development of fast, low-noise, radiation hard and low-power electronics readout for the counters. The final aim is the construction of a prototype detector capable of operating at LHC.

  14. Track finding and fitting in the H1 Forward Track Detector

    International Nuclear Information System (INIS)

    Burke, S.; Henderson, R.C.W.; Maxfield, S.J.; Patel, G.D.; Morris, J.V.; Sankey, D.P.C.; Skillicorn, I.O.

    1995-07-01

    The tracking environment in the H1 Forward Tracker Detector, where the hit multiplicity from proton fragments is high, is parituclarly hostile. The techniques and software which have been developed for pattern recognition and Kalman fitting of charged particle tracks in this region are described in detail. (orig.)

  15. Apatite fission track evidence on the uplifting of eastern Kunlun mountains

    International Nuclear Information System (INIS)

    Yuang Wanming; Dong Jinquan; Tang Yunhui; Wang Shicheng

    2004-01-01

    A series of samples were collected from about south-north section through Buqingshan and Dulan, eastern Kunlun mountains, China. The 41 apatite fission track ages (FTA) of these samples lie between 25.2 and 130.4 Ma, all of the apatite fission track ages are significantly younger than the host rocks. There are similar evolution trends for Middle-Kunlun zone and North-Kunlun zone, i.e. the FTA becomes less with slow increase of elevations and their uplifting rates are about 2.22 m/Ma. Differently, the FTA in South-Kunlun zone positively correlates to elevation, decreasing 11 m/Ma. It may be shown that South-Kunlun fault play a different and/or more important role on incontinent evolution than Middle-Kunlun fault. (author)

  16. Uranium concentration in blood samples of Southern Iraqi leukemia patients using CR-39 track detector

    International Nuclear Information System (INIS)

    Al-Hamzawi, A.A.; Al-Qadisiyah University, Qadisiyah; Jaafar, M.S.; Tawfiq, N.F.

    2014-01-01

    The simple and effective technique of fission track etch has been applied to determine trace concentration of uranium in human blood samples taken from two groups of male and female participants: leukemia patients and healthy subjects group. The blood samples of leukemia patients and healthy subjects were collected from three key southern governorates namely, Basrah, Muthanna and Dhi-Qar. These governorates were the centers of intensive military activities during the 1991 and 2003 Gulf wars, and the discarded weapons are still lying around in these regions. CR-39 track detector was used for registration of induced fission tracks. The results show that the highest recorded uranium concentration in the blood samples of leukemia patients was 4.71 ppb (female, 45 years old, from Basrah) and the minimum concentration was 1.91 ppb (male, 3 years old, from Muthanna). For healthy group, the maximum uranium concentration was 2.15 ppb (female, 55 years old, from Basrah) and the minimum concentration was 0.86 ppb (male, 5 years old, from Dhi-Qar). It has been found that the uranium concentrations in human blood samples of leukemia patients are higher than those of the healthy group. These uranium concentrations in the leukemia patients group were significantly different (P < 0.001) from those in the healthy group. (author)

  17. Uranium concentration measurements in human blood for some governorates in Iraq using CR-39 track detector

    International Nuclear Information System (INIS)

    Tawfiq, N.F.; Ali, L.T.; Al-Jobouri, H.A.

    2013-01-01

    The sensitive and simple technique of fission track etch has been applied to determine trace concentration of uranium in blood samples for occupational and non-occupational workers, male and female, using CR-39 track detector that is employed for registration of induced fission tracks. The results show that the highest recorded uranium concentration in human blood of workers in the ministry of Science and Technology were 1.90 ppb (male, 36 years old, 12 years' work experience, and living in Basrah governorate) and minimum concentration 0.26 ppb (female, 40 years old, 10 years' work experience, and living in Baghdad), while for non-occupational worker, the maximum uranium concentration was 1.76 ppb (female, 63 years old, and living in Al-Muthana) and minimum concentration was 0.28 ppb (female, 20 years old, and living in Baghdad). It has also been found that the uranium concentration in human blood samples of workers in the ministry of Science and Technology are higher than those of non-occupational workers, and the uranium concentrations for female workers and for non-occupational workers were higher than those for male workers and non-occupational workers. (author)

  18. Image formation in track-etch detectors: Pt. 4

    International Nuclear Information System (INIS)

    Ilic, Radomir; Najzer, Mitja

    1990-01-01

    The radiographic performance of solid state nuclear track detectors was analysed with respect to image quality. Image quality is expressed in terms of three image quality factors: contrast or gradient of the detector, image unsharpness and detail discernment. Equations for the image quality factors were derived from the radiographic transfer function, taking into account image inhomogeneity caused by statistical fluctuations of track density. To find optimal radiographic conditions for a given application, a single quantity called the figure of radiographic merit was defined. It is expressed as the weighted product of the image quality factors. It was found that optimum image quality of a balanced image, characterized by equal importance of all three image quality factors, is obtained at an exposure value (defined as the product of the average visible track area and track density) of unity. (author)

  19. A fast neutron detector with IP by track measurement

    International Nuclear Information System (INIS)

    Miao Zhengqiang; Yang Jun; Zhang Qiang; Zhao Xiangfeng; Wang Daohua

    2004-01-01

    Imaging Plate(IP) is very sensitive to electric particles, especially to heavy ions. As we know, the recoiling protons are produced while fast neutrons scattered in light material containing hydrogen. When the recoiling proton enters in the sensitive layer of IP, a track will be recorded by IP. In this paper, a fast neutron detector based on IP and (n, p) reaction is described in detail, the detector's efficiency is studied also. (authors)

  20. Studies on neutron detection with solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Khouri, M.C.; Vilela, E.C.; Andrade, C. de.

    1993-03-01

    The detection of thermal and fast neutrons was studied. For thermal neutrons, alpha sensitive plastic was used in order to register the products of nuclear reactions taking place in boron and /or lithium converters. Fast neutrons produce recoil tracks within the detector. In the present case, CR-39 and Makrofol E were used. Chemical and electrochemical etching processes were used for thermal and fast neutron detectors, respectively. (F.E.). 6 refs, 4 figs, 6 tabs

  1. Observation of anomalons in CR-39 track detectors

    International Nuclear Information System (INIS)

    Tincknell, M.L.; Price, P.B.

    1984-01-01

    The authors have observed fragments of 1.85 GeV/nucleon 40 Ar in CR-39 etched track detector and they find anomalously short mean free paths (mfp's) of secondary nuclei with 11 less than or equal to Z less than or equal to 17 in the first 2 cm after their production, at approx.3 standard deviations. This confirms previous reports of this anomalon effect in nuclear emulsion in a new detector with dissimilar potential systematic errors

  2. Evaluation of a digital optical ionizing radiation particle track detector

    International Nuclear Information System (INIS)

    Hunter, S.R.

    1987-06-01

    An ionizing radiation particle track detector is outlined which can, in principle, determine the three-dimensional spatial distribution of all the secondary electrons produced by the passage of ionizing radiation through a low-pressure (0.1 to 10 kPa) gas. The electrons in the particle track are excited by the presence of a high-frequency AC electric field, and two digital cameras image the optical radiation produced in electronic excitation collisions of the surroundings gas by the electrons. The specific requirements of the detector for neutron dosimetry and microdosimetry are outlined (i.e., operating conditions of the digital cameras, high voltage fields, gas mixtures, etc.) along with an estimate of the resolution and sensitivity achievable with this technique. The proposed detector is shown to compare favorable with other methods for obtaining the details of the track structure, particularly in the quality of the information obtainable about the particle track and the comparative simplicity and adaptability of the detector for measuring the secondary electron track structure for many forms of ionizing radiation over a wide range of energies

  3. Apatite fission-track dating of erosion in the eastern Andes, Bolivia

    International Nuclear Information System (INIS)

    Crough, S.T.

    1983-01-01

    Three samples from a Triassic-age batholith in the eastern Andes northeast of La Paz, Bolivia yield apatitic fission-track ages of 11-13 Ma. Interpreting these young ages as due to uplift and erosion requires approximately 2.5-5.0 km of erosion in the past 12 Ma, an amount which is consistent with the known geology and which is typical of many active mountain ranges. (orig.)

  4. Fission track ages and uranium concentration of apatites of different rocks of South India

    International Nuclear Information System (INIS)

    Nand Lal; Nagpaul, K.K.; Nagpal, M.K.

    1975-01-01

    The uranium concentration and ages of apatite grains of various rocks of South India have been measured by fission track technique. The ages range from 100 m.y. to 730 m.y. whereas uranium concentrations vary from 0.5 to 23.8 atom/million atoms of the apatite mineral. The ages agree well with the Deccan volcanic and Ocean Cycle activities. (author)

  5. Use of fission track for deciphering the dissolution mechanism of silicates glasses

    International Nuclear Information System (INIS)

    Petit, J.C.; Brousse, C.

    1985-09-01

    Polished sections of silicate glasses containing latent or pre-etched fission tracks have been subjected to corrosion in deionized water or NaCl brines at 20, 50 and 100 0 C. The evolution of glass surface helps deciphering among reported dissolution models. We show that ion-exchange is dominant in simple glasses while in complex ones, dissolution involves several steps including an in-situ transformation of the pristine material and a reprecipitation of dissolved species

  6. Detectors for Linear Colliders: Tracking and Vertexing (2/4)

    CERN Multimedia

    CERN. Geneva

    2010-01-01

    Efficient and precise determination of the flavour of partons in multi-hadron final states is essential to the anticipated LC physics program. This makes tracking in the vicinity of the interaction region of great importance. Tracking extrapolation and momentum resolution are specified by precise physics requirements. The R&D towards detectors able to meet these specifications will be discussed, together with some of their application beyond particle physics.

  7. Calibration and alignment of the CMS silicon tracking detector

    International Nuclear Information System (INIS)

    Stoye, M.

    2007-07-01

    The Large Hadron Collider (LHC) will dominate the high energy physics program in the coming decade. The discovery of the standard model Higgs boson and the discovery of super-symmetric particles are within the reach at the energy scale explored by the LHC. However, the high luminosity and the high energy of the colliding protons lead to challenging demands on the detectors. The hostile radiation environment requires irradiation hard detectors, where the innermost subdetectors, consisting of silicon modules, are most affected. This thesis is devoted to the calibration and alignment of the silicon tracking detector. Electron test beam data, taken at DESY, have been used to investigate the performance of detector modules which previously were irradiated with protons up to a dose expected after 10 years of operation. The irradiated sensors turned out to be still better than required. The performance of the inner tracking systems will be dominated by the degree to which the positions of the sensors can be determined. Only a track based alignment procedure can reach the required precision. Such an alignment procedure is a major challenge given that about 50000 geometry constants need to be measured. Making use of the novel χ 2 minimization program Millepede II an alignment strategy has been developed in which all detector components are aligned simultaneously, as many sources of information as possible are used, and all correlations between the position parameters of the detectors are taken into account. Utilizing simulated data, a proof of concept of the alignment strategy is shown. (orig.)

  8. Calibration and alignment of the CMS silicon tracking detector

    Energy Technology Data Exchange (ETDEWEB)

    Stoye, M.

    2007-07-15

    The Large Hadron Collider (LHC) will dominate the high energy physics program in the coming decade. The discovery of the standard model Higgs boson and the discovery of super-symmetric particles are within the reach at the energy scale explored by the LHC. However, the high luminosity and the high energy of the colliding protons lead to challenging demands on the detectors. The hostile radiation environment requires irradiation hard detectors, where the innermost subdetectors, consisting of silicon modules, are most affected. This thesis is devoted to the calibration and alignment of the silicon tracking detector. Electron test beam data, taken at DESY, have been used to investigate the performance of detector modules which previously were irradiated with protons up to a dose expected after 10 years of operation. The irradiated sensors turned out to be still better than required. The performance of the inner tracking systems will be dominated by the degree to which the positions of the sensors can be determined. Only a track based alignment procedure can reach the required precision. Such an alignment procedure is a major challenge given that about 50000 geometry constants need to be measured. Making use of the novel {chi}{sup 2} minimization program Millepede II an alignment strategy has been developed in which all detector components are aligned simultaneously, as many sources of information as possible are used, and all correlations between the position parameters of the detectors are taken into account. Utilizing simulated data, a proof of concept of the alignment strategy is shown. (orig.)

  9. The in-beam tracking detectors for R3B

    Energy Technology Data Exchange (ETDEWEB)

    Paschalis, Stefanos; Johansen, Jacob; Scheit, Heiko [Institut fuer Kernphysik, Technische Universitaet, D 64289 Darmstadt (Germany); Heil, Michael [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Aumann, Thomas [Institut fuer Kernphysik, Technische Universitaet, D 64289 Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Krivshich, Anatoly [PNPI St. Petersburg, 188300 Gatchina (Russian Federation); Collaboration: R3B-Collaboration

    2015-07-01

    The R3B experiment is part of the NUSTAR pillar at FAIR. One of the great strengths of the R3B experiment is the kinematically complete measurement of reactions with exotic ions with energies of up to 1 AGeV. Key components of the R3B experiment are the neutron detector NeuLAND, the γ and charge-particle calorimeter CALIFA, the Si Tracker and the in-beam tracking detectors. A cornerstone instrument of the setup is the new dipole magnet (GLAD) which bends and momentum analyses the high-rigidity beams. A precise tracking of the charged particles through the magnetic field is crucial to resolve the masses of heavy ions and measure the momentum of the fragments with high resolution. In this contribution we present the technical design details of the in-beam tracking detectors that will be used in the R3B experiment together with recent results obtained from in-beam prototype testing. In particular, we discuss Si detectors, detectors based on plastic-scintillator fibers and paddles, straw-tube gas detectors and the overall performance of the system.

  10. Radiation damage studies of mineral apatite, using fission tracks and thermoluminescence techniques

    International Nuclear Information System (INIS)

    Al-Khalifa, I.J.M.

    1988-01-01

    In a uranium (/thorium)-rich mineral sample which has not suffered a recent geological high-temperature excursion, the fossil fission track density (FFTD) will give a good indication of its natural radiation damage, provided that its U/Th ratio is known. From our studies of FFTD and thermoluminescence (TL) properties of several samples of apatite from different locations, and containing varying degrees of natural-radiation damage, an anti-correlation is observed between FFTD and TL sensitivity. It is also found that an anti-correlation exists between TL sensitivity and the amount of damage produced artificially by bombarding apatite crystals with different fluences of ∼30 MeV α-particles from a cyclotron. These results indicate that the presence of radiation damage in this mineral (viz., fluorapatite) can severely affect its TL sensitivity (i.e. TL output per unit test dose). The effect of crystal composition on the thermoluminescence and fission track annealing properties of mineral apatite is also reported. We have found that fission track annealing sensitivity and TL sensitivity are both significantly lower in samples of chlorapatite than in samples consisting predominantly of fluorapatite. (author)

  11. Thermal history of rocks in southern San Joaquin Valley, California: evidence from fission-track analysis

    Science.gov (United States)

    Naeser, N.D.; Naeser, C.W.; McCulloh, T.H.

    1990-01-01

    Fission-track analysis has been used to study the thermal and depositional history of the subsurface Tertiary sedimentary rocks on both sides of the active White Wolf reverse fault in the southern San Joaquin Valley. The distinctly different thermal histories of the rocks in the two structural blocks are clearly reflected in the apatite fission-track data, which suggest that rocks in the rapidly subsiding basin northwest of the fault have been near their present temperature for only about 1 m.y. compared with about 10 m.y. for rocks southeast of the fault. These estimates of heating time agree with previous estimates for these rocks. Zircon fission-track data indicate that the Tertiary sediments were derived from parent rocks of more than one age. However, from at least the Eocene to late Miocene or Pliocene, the major sediment source was rocks related to the youngest Sierra Nevada Mesozoic intrusive complexes, which are presently exposed east and south of the southern San Joaquin Valley. -from Authors

  12. Fission-track ages of Neogene and Quaternary volcanic ashes in south of Osaka, Japan

    International Nuclear Information System (INIS)

    Yokoyama, Takuo; Nakagawa, Yonosuke; Danhara, Tohru.

    1984-01-01

    A calculation method is proposed for the fission-track ages of zircon crystals in volcanic material. In this method, it is checked whether the spontaneous fission-track number of respective zircon crystals follows the Poisson distribution. If it does, the age is calculated by population method with all crystals, and if not, only with those crystals following the Poisson distribution, eliminating abnormal crystals. Extraneous zircon crystals are thus excluded and crystals with spontaneous fission-track number zero are not ignored. The following ages were obtained: Tamateyama volcanic ash in the Nijo group, 14.0 +- 0.6 Ma; pink volcanic ash in the Osaka group, 1.0 +- 0.2 Ma; Matsuo volcanic ash in the Ko-Osaka group, 1.5 +- 0.4 Ma; pumice volcanic ash in the Ko-Osaka group, 2.3 +- 0.4 Ma; Asashiro volcanic ash in the Ko-Osaka group, 2.9 +- 0.6 Ma. (Mori, K.)

  13. Superheavy-element fission tracks in iron meteorites, and reply by Bull, R.K

    International Nuclear Information System (INIS)

    Runcorn, S.K.

    1980-01-01

    Comment is made on the lack of superheavy element (SHE) fission tracks observed in silicates from the class IA Odessa iron meteorite by Bull (Nature; 282:393 (1979)). Two explanations are suggested. Firstly, a thermal history for Odessa can be constructed in which the meteorite reaches track retention temperatures only after a time corresponding to many half lives for the SHEs (taken to be approximately 100 Myr) has elapsed and secondly that the IA irons never took up many SHEs. These suggestions are discussed in a reply by Bull. (U.K.)

  14. Extrapolation of zircon fission-track annealing models

    International Nuclear Information System (INIS)

    Palissari, R.; Guedes, S.; Curvo, E.A.C.; Moreira, P.A.F.P.; Tello, C.A.; Hadler, J.C.

    2013-01-01

    One of the purposes of this study is to give further constraints on the temperature range of the zircon partial annealing zone over a geological time scale using data from borehole zircon samples, which have experienced stable temperatures for ∼1 Ma. In this way, the extrapolation problem is explicitly addressed by fitting the zircon annealing models with geological timescale data. Several empirical model formulations have been proposed to perform these calibrations and have been compared in this work. The basic form proposed for annealing models is the Arrhenius-type model. There are other annealing models, that are based on the same general formulation. These empirical model equations have been preferred due to the great number of phenomena from track formation to chemical etching that are not well understood. However, there are two other models, which try to establish a direct correlation between their parameters and the related phenomena. To compare the response of the different annealing models, thermal indexes, such as closure temperature, total annealing temperature and the partial annealing zone, have been calculated and compared with field evidence. After comparing the different models, it was concluded that the fanning curvilinear models yield the best agreement between predicted index temperatures and field evidence. - Highlights: ► Geological data were used along with lab data for improving model extrapolation. ► Index temperatures were simulated for testing model extrapolation. ► Curvilinear Arrhenius models produced better geological temperature predictions

  15. Capillary detectors for high resolution tracking

    International Nuclear Information System (INIS)

    Annis, P.; Bay, A.; Bonekaemper, D.; Buontempo, S.; Ereditato, A.; Fabre, J.P.; Fiorillo, G.; Frekers, D.; Frenkel, A.; Galeazzi, F.; Garufi, F.; Goldberg, J.; Golovkin, S.; Hoepfner, K.; Konijn, J.; Kozarenko, E.; Kreslo, I.; Liberti, B.; Martellotti, G.; Medvedkov, A.; Mommaert, C.; Panman, J.; Penso, G.; Petukhov, Yu.; Rondeshagen, D.; Tyukov, V.; Vasilchenko, V.; Vilain, P.; Vischers, J.L.; Wilquet, G.; Winter, K.; Wolff, T.; Wong, H.

    1997-01-01

    We present a new tracking device based on glass capillary bundles or layers filled with highly purified liquid scintillator and read out at one end by means of image intensifiers and CCD devices. A large-volume prototype consisting of 5 x 10 5 capillaries with a diameter of 20 μm and a length of 180 cm and read out by a megapixel CCD has been tested with muon and neutrino beams at CERN. With this prototype a two track resolution of 33 μm was achieved with passing through muons. Images of neutrino interactions in a capillary bundle have also been acquired and analysed. Read-out chains based on electron bombarded CCD (EBCCD) and image pipeline devices are also investigated. Preliminary results obtained with a capillary bundle read out by an EBCCD are presented. (orig.)

  16. Capillary detectors for high resolution tracking

    CERN Document Server

    Annis, P

    1997-01-01

    We present a new tracking device based on glass capillary bundles or layers filled with highly purified liquid scintillator and read out at one end by means of image intensifiers and CCD devices. A large-volume prototype consisting of 5 × 105 capillaries with a diameter of 20 μm and a length of 180 cm and read out by a megapixel CCD has been tested with muon and neutrino beams at CERN. With this prototype a two track resolution of 33 μm was achieved with passing through muons. Images of neutrino interactions in a capillary bundle have also been acquired and analysed. Read-out chains based on Electron Bombarded CCD (EBCCD) and image pipeline devices are also investigated. Preliminary results obtained with a capillary bundle read out by an EBCCD are presented.

  17. Tracking with heavily irradiated silicon detectors operated at cryogenic temperatures

    International Nuclear Information System (INIS)

    Casagrande, L.; Barnett, B.M.; Bartalina, P.

    1999-01-01

    In this work, the authors show that a heavily irradiated double-sided silicon microstrip detector recovers its performance when operated at cryogenic temperatures. A DELPHI microstrip detector, irradiated to a fluence of ∼4 x 10 14 p/cm 2 , no longer operational at room temperature, cannot be distinguished from a non-irradiated one when operated at T < 120 K. Besides confirming the previously observed Lazarus effect in single diodes, these results establish, for the first time, the possibility of using standard silicon detectors for tracking applications in extremely demanding radiation environments

  18. Thermal annealing of fission tracks in fluorapatite, chlorapatite, manganoanapatite, and Durango apatite: experimental results

    International Nuclear Information System (INIS)

    Ravenhurst, C.E.; Roden-Tice, M.K.; Miller, D.S.

    2003-01-01

    It is well known that the optically measured lengths of fission tracks in apatite crystals are a function of etching conditions, crystallographic orientation of the track, composition of the crystal, and the state of thermal annealing. In this study we standardize etching conditions and optimize track length measurability by etching until etch pits formed at the surface of each apatite crystal reached widths of about 0.74 μm. Etching times using 5M HNO 3 at 21 o C were 31 s for Otter Lake, Quebec, fluorapatite; 47 s for Durango, Mexico, apatite; 33 s for Portland, Connecticut, manganoanapatite; and 11 s for Bamle, Norway, chlorapatite. An etching experiment using two etchant strengths (5M and 1.6M HNO 3 ) revealed that, despite significant differences in etch pit shape, fission-track length anisotropy with respect to crystallographic orientation of the tracks is not a chemical etching effect. A series of 227 constant-temperature annealing experiments were carried out on nuclear reactor induced tracks in oriented slices of the apatites. After etching, crystallographic orientations of tracks were measured along with their lengths. The 200-300 track lengths measured for each slice were ellipse-fitted to give the major (c crystallographic direction) and minor (a crystallographic direction) semi-axes used to calculate equivalent isotropic lengths. The equivalent isotropic length is more useful than mean length for thermal history analysis because the variation caused by anisotropy has been removed. Using normalized etching procedures and equivalent isotropic length data, we found that the fluorapatite anneals most readily, followed by Durango apatite, manganoanapatite, and lastly chlorapatite. (author)

  19. Radon detection in soils by solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Moraes, M.A.P.V. de; Khouri, M.T.F.C.

    1986-01-01

    The solid state nuclear track detectors technique was developed to be used in radon detection, by alpha particles tracks, and its application in uranium prospecting on the ground. The sensitive films to alpha particles used are the cellulose nitrate films LR 115 and CA 8015. Several simulations experiments and field measurements were carried out to verify the method possibilities. Maps of some anomalies in Caetite City (Bahia, Brazil) were made with the densities of tracks obtained. The results were compared with scintillation counter measurements. (Author) [pt

  20. Discovery Mondays - The detectors: tracking particles

    CERN Multimedia

    2005-01-01

    View of a module from the LHCb vertex detector, which will be presented at the next Discovery Monday. How do you observe the invisible? In order to deepen still further our knowledge of the infinitely small, physicists accelerate beams of particles at close to the speed of light, then generate collisions between them at extraordinary energies, giving birth to showers of new particles. What are these particles? In order to find out, physicists transform themselves into detectives with the help of the detectors. Located around the collision area, these exceptional machines are made up of various layers, each of which detects and measures specific properties of the particles that travel through them. Powerful computers then reconstruct their trajectory and record their charge, mass and energy in order to build up a kind of particle ID card. At the next Discovery Monday you will be able to find out about the different methods used at CERN to detect particles. A cloud chamber will provide live images of the trac...

  1. Calculation of track and vertex errors for detector design studies

    International Nuclear Information System (INIS)

    Harr, R.

    1995-01-01

    The Kalman Filter technique has come into wide use for charged track reconstruction in high-energy physics experiments. It is also well suited for detector design studies, allowing for the efficient estimation of optimal track covariance matrices without the need of a hit level Monte Carlo simulation. Although much has been published about the Kalman filter equations, there is a lack of previous literature explaining how to implement the equations. In this paper, the operators necessary to implement the Kalman filter equations for two common detector configurations are worked out: a central detector in a uniform solenoidal magnetic field, and a fixed-target detector with no magnetic field in the region of the interactions. With the track covariance matrices in hand, vertex and invariant mass errors are readily calculable. These quantities are particularly interesting for evaluating experiments designed to study weakly decaying particles which give rise to displaced vertices. The optimal vertex errors are obtained via a constrained vertex fit. Solutions are presented to the constrained vertex problem with and without kinematic constraints. Invariant mass errors are obtained via propagation of errors; the use of vertex constrained track parameters is discussed. Many of the derivations are new or previously unpublished

  2. Some aspects of solid track detector usage in ecological research

    International Nuclear Information System (INIS)

    Berzina, I.G.; Gusev, E.B.; Ivanov, V.A.

    1991-01-01

    The ability of plants to accumulate large quantities of uranium in areas with unfavorable environmental conditions caused by the open working of various deposits and the mining of uranium containing minerals is discussed. The experimental data show the need for qualitative and quantitative revisions of radiation safety levels. Aspects of the use of solid state track detectors in this research are presented. (author)

  3. Particularization of alpha contamination using CR-39 track detectors

    Indian Academy of Sciences (India)

    detecting devices and as a passive system to detect alpha contamination on different sur- faces. This work presents ... these plastic detectors can be cut into sizes and shapes according to the specific area that has to be ... of nuclear track materials observed under a microscope, after chemical etching for the same time and ...

  4. A gamma-ray tracking detector for molecular imaging

    International Nuclear Information System (INIS)

    Hall, C.J.; Lewis, R.A.; Helsby, W.I.; Nolan, P.; Boston, A.

    2003-01-01

    A design for a gamma-ray detector for molecular imaging is presented. The system is based on solid-state strip detector technology. The advantages of position sensitivity coupled with fine spectral resolution are exploited to produce a tracking detector for use with a variety of isotopes in nuclear medicine. Current design concepts employ both silicon and germanium layers to provide an energy range from 60 keV to >1 MeV. This allows a reference X-ray image to be collected simultaneously with the gamma-ray image providing accurate anatomical registration. The tracking ability of the gamma-ray detector allows ambiguities in the data set to be resolved which would otherwise cause events to be rejected in standard non-tracking system. Efficiency improvements that high solid angle coverage and the use of a higher proportion of events make time resolved imaging and multi-isotope work possible. A modular detector system, designed for viewing small animals has been accepted for funding

  5. Technologies for Future Vertex and Tracking Detectors at CLIC

    CERN Document Server

    Spannagel, Simon

    2018-01-01

    CLIC is a proposed linear e$^{+}$e$^{-}$ collider with center-of-mass energies of up to 3 TeV. Its main objectives are precise top quark and Higgs boson measurements, as well as searches for Beyond Standard Model physics. To meet the physics goals, the vertex and tracking detectors require not only a spatial resolution of a few micrometers and a very low material budget, but also timing capabilities with a precision of a few nanoseconds to allow suppression of beam-induced backgrounds. Different technologies using hybrid silicon detectors are explored for the vertex detectors, such as dedicated readout ASICs, small-pitch active edge sensors as well as capacitively coupled High-Voltage CMOS sensors. Monolithic sensors are considered as an option for the tracking detector, and a prototype using a CMOS process with a high-resistivity epitaxial layer is being designed. Different designs using a silicon-on-insulator process are under investigation for both vertex and tracking detector. All prototypes are evaluate...

  6. Application of solid state track detector to neutron dosimetry

    International Nuclear Information System (INIS)

    Tsuruta, Takao

    1979-01-01

    Though solid state track detectors (SSTD) are radiation measuring instrument for heavy charged particles by itself, it can be used as radiation measuring instrument for neutrons, if nuclear reactions such as (n, f) or (n, α) reaction are utilized. Since the means was found, which permits to observe the tracks of heavy charged particles in a solid with an optical microscope by chemically etching the tracks to enlarge them to etch pits, various types of detectors have been developed for the purpose of measuring neutron dose. The paper is described on the materials and construction of the SSTDs for neutron dosimetry, and the sensitivity is explained with mathematical equations. The features of neutron dosimetry with SSTDs are as follows: They are compact, and scarcely disturb neutron field, thus delicate dose distribution can be known; integration measurement is possible regardless of dose rate values because of integrating type detectors; it is not influenced by β-ray or γ-ray except the case when there is high energy radiation such as causing photonuclear reactions or high dose such as degrading solids, it has pretty high sensitivity; track fading is negligible during the normal measuring time around room temperature; and the etching images of tracks are relatively clear, and various automatic counting systems can be employed. (Wakatsuki, Y.)

  7. Particularisation of Alpha Contamination using CR-39 Track Detectors

    International Nuclear Information System (INIS)

    Zakia, M.F.; El-Shaer, Y.H.

    2008-01-01

    Solid-state nuclear track detectors have found wide use in various domains of science and technology, e.g. in environmental experiments. The measurement of alpha activity on sources in an environment, such as air is not easy because of short penetration range of the alpha particles. Furthermore, the measurement of alpha activity by most gas ionization detectors suffers from the high background induced by the accompanying gamma radiation. Solid State Nuclear Track Detectors (SSNTDs) have been used successfully as detecting devices as passive system to detect the alpha contamination different surfaces. This work presents the response of CR-39 (for two types) to alpha particles from two sources, 238 Pu with energy 5 MeV and 241 Am with energy 5.4 MeV. The methods of etching and counting are investigated, along with the achievable linearity, efficiency and reproducibility. The sensitivity to low activity and energy resolution are studied

  8. Radon measurements technique in air using a track plastic detector

    International Nuclear Information System (INIS)

    Pereira, J.F.A.; Silva Estrada, J.J. da; Binns, D.A.C.; Urban, M.

    1983-01-01

    A difusion chamber is used to measure the radon concentration in air through alpha particles tracks in Makrofol E, 300μm thick. This system was developed by Karlsruhe Nuclear Research Centre, Germany, and is already used by the Occupational Radiological Protection Department of IRD/CNEN, for premilimar measurements in Pocos de Caldas and Rio de Janeiro. In the chamber, the plastic detector is set at the lower end and a filter is placed at the upper end. In this way, a known volume is defined in the detector system. To amplify the tracks produced by the alpha particles due to radon and short-lived dadon-daughter products, an electrochemical system is employed. Some theoretical questions about the treeing produced by the electrochemical etching, the detector characteristics, as well as the adapted statistics model are also discussed. (Author) [pt

  9. Range measurements and track kinetics in Dielectric Nuclear Track Detectors (DNTDs)

    Energy Technology Data Exchange (ETDEWEB)

    Aframian, A

    1981-01-01

    Observations of nuclear track development profiles and the kinetics of etched tracks in sensitive dielectric nuclear track detectors indicate three separate phases: the inception phase or the cone phase, the transition phase and the sphere phase. Continued etching of the sphere phase to through-tracks yields accurate range data for particles of different masses and energies and minimum critical angles of registration for each particle. The present results show an energy resolution of 40 keV (fwhm) for 5.48 MeV alpha-particles emitted from Am-241.

  10. A twin Frisch-grid ionization chamber as a selective detector for the delayed gamma-spectroscopy of fission fragments

    Energy Technology Data Exchange (ETDEWEB)

    Gaudefroy, L., E-mail: laurent.gaudefroy@cea.fr [CEA, DAM, DIF, F-91297 Arpajon (France); Roger, T., E-mail: roger@ganil.fr [GANIL, CEA/DSM-CNRS/IN2P3, BP 55027, F-14076 Caen (France); Pancin, J., E-mail: pancin@ganil.fr [GANIL, CEA/DSM-CNRS/IN2P3, BP 55027, F-14076 Caen (France); Spitaels, C. [GANIL, CEA/DSM-CNRS/IN2P3, BP 55027, F-14076 Caen (France); Aupiais, J. [CEA, DAM, DIF, F-91297 Arpajon (France); Mottier, J. [Institut de Physique Nucléaire, Université Paris-Sud-11-CNRS-IN2P3, F-91406 Orsay (France)

    2017-05-21

    We present a twin Frisch-grid ionization chamber. The detector is meant to provide high selective power for the study of delayed gamma-ray spectroscopy of fission fragments produced via {sup 252}Cf spontaneous fission. A mean energy resolution on the kinetic energy of fission fragments of 675 keV (FWHM) is achieved and allows us to resolve masses of fragments for fission events where neutron emission is not energetically possible. The mean mass resolution measured for these particular events amounts to 0.54 mass units (FWHM). For fission events with neutron emission a resolution of 4 mass units (FWHM) is reported. Information on fragment emission angle is measured with a resolution of 0.1 on the difference of the cosines determined for both halves of the detector. A charge resolution of 4.5 charge units (FWHM) is also demonstrated.

  11. The use of CH3OH additive to NaOH for etching alpha particle tracks in a CR-39 plastic nuclear track detector

    International Nuclear Information System (INIS)

    Ashry, A.H.; Abdalla, A.M.; Rammah, Y.S.; Eisa, M.; Ashraf, O.

    2014-01-01

    Fast detection of alpha particles in CR-39 detectors was investigated using a new chemical etchant. 252 Cf and 241 Am sources were used for irradiating samples of CR-39 SSNTDs with fission fragments and alpha particles in air at normal temperature and pressure. A series of experimental chemical etching are carried out using new etching solution (8 ml of 10N NaOH+1 ml CH 3 OH) at 60 °C to detect alpha particle in short time in CR-39 detectors. Suitable analyzing software has been used to analyze experimental data. From fission and alpha track diameters, the value of bulk etching rate is equal to 2.73 μm/h. Both the sensitivity and etching efficiency were found to vary with the amount of methanol in the etching solution. Pure NaOH was used as a control to compare with the result from etching in NaOH with different concentrations of CH 3 OH. The etching efficiency is determined and compared with conventional aqueous solution of 6.25N NaOH at 70 °C for etching time equals 5 h. In this study, the obtained etching efficiency shows a considerable agreement with the previous work. - Highlights: • The value of bulk etching rate is equal to 2.73 μm/h. • Fast detection of alpha particles in CR-39 detectors. • Samples of CR-39 have been irradiated with fission fragments. • Etching efficiency was determined

  12. Fission-product yields for thermal-neutron fission of 243Cm determined from measurements with a high-resolution low-energy germanium gamma-ray detector

    International Nuclear Information System (INIS)

    Merriman, L.D.

    1984-04-01

    Cumulative fission-product yields have been determined for 13 gamma rays emitted during the decay of 12 fission products created by thermal-neutron fission of 243 Cm. A high-resolution low-energy germanium detector was used to measure the pulse-height spectra of gamma rays emitted from a 77-nanogram sample of 243 Cm after the sample had been irradiated by thermal neutrons. Analysis of the data resulted in the identification and matching of gamma-ray energies and half-lives to individual radioisotopes. From these results, 12 cumulative fission product yields were deduced for radionuclides with half-lives between 4.2 min and 84.2 min. 7 references

  13. A Vertex and Tracking Detector System for CLIC

    CERN Document Server

    AUTHOR|(SzGeCERN)718101

    2017-01-01

    The physics aims at the proposed future CLIC high-energy linear $e^+e^−$ collider pose challenging demands on the performance of the detector system. In particular the vertex and tracking detectors have to combine precision measurements with robustness against the expected high rates of beam-induced backgrounds. The requirements include ultra-low mass, facilitated by power pulsing and air cooling in the vertex-detector region, small cell sizes and precision hit timing at the few-ns level. A detector concept meeting these requirements has been developed and an integrated R&D program addressing the challenges is progressing in the areas of ultra-thin sensors and readout ASICs, interconnect technology, mechanical integration and cooling.

  14. On Use of Multi-Chambered Fission Detectors for In-Core, Neutron Spectroscopy

    Science.gov (United States)

    Roberts, Jeremy A.

    2018-01-01

    Presented is a short, computational study on the potential use of multichambered fission detectors for in-core, neutron spectroscopy. Motivated by the development of very small fission chambers at CEA in France and at Kansas State University in the U.S., it was assumed in this preliminary analysis that devices can be made small enough to avoid flux perturbations and that uncertainties related to measurements can be ignored. It was hypothesized that a sufficient number of chambers with unique reactants can act as a real-time, foilactivation experiment. An unfolding scheme based on maximizing (Shannon) entropy was used to produce a flux spectrum from detector signals that requires no prior information. To test the method, integral, detector responses were generated for singleisotope detectors of various Th, U, Np, Pu, Am, and Cs isotopes using a simplified, pressurized-water reactor spectrum and fluxweighted, microscopic, fission cross sections, in the WIMS-69 multigroup format. An unfolded spectrum was found from subsets of these responses that had a maximum entropy while reproducing the responses considered and summing to one (that is, they were normalized). Several nuclide subsets were studied, and, as expected, the results indicate inclusion of more nuclides leads to better spectra but with diminishing improvements, with the best-case spectrum having an average, relative, group-wise error of approximately 51%. Furthermore, spectra found from minimum-norm and Tihkonov-regularization inversion were of lower quality than the maximum entropy solutions. Finally, the addition of thermal-neutron filters (here, Cd and Gd) provided substantial improvement over unshielded responses alone. The results, as a whole, suggest that in-core, neutron spectroscopy is at least marginally feasible.

  15. Alignment of the ATLAS Inner Detector Tracking System

    CERN Document Server

    Moles-Valls, R

    2008-01-01

    The ATLAS experiment is equipped with a tracking system for c harged particles built on two technologies: silicon and drift tube base detectors. These kind of detectors compose the ATLAS Inner Detector (ID). The Alignment of the ATLAS ID tracking s ystem requires the determination of almost 36000 degrees of freedom. From the tracking point o f view, the alignment parameters should be know to a few microns precision. This permits to att ain optimal measurements of the parameters of the charged particles trajectories, thus ena bling ATLAS to achieve its physics goals. The implementation of the alignment software, its framewor k and the data flow will be discussed. Special attention will be paid to the recent challenges wher e large scale computing simulation of the ATLAS detector has been performed, mimicking the ATLAS o peration, which is going to be very important for the LHC startup scenario. The alignment r esult for several challenges (real cosmic ray data taking and computing system commissioning) will be...

  16. Optimizing moderation of He-3 neutron detectors for shielded fission sources

    Energy Technology Data Exchange (ETDEWEB)

    Rees, Lawrence B., E-mail: Lawrence_Rees@byu.edu [Department of Physics and Astronomy, Brigham Young University, Provo, UT 84602 (United States); Czirr, J. Bart, E-mail: czirr@juno.com [Department of Physics and Astronomy, Brigham Young University, Provo, UT 84602 (United States)

    2012-11-01

    The response of a {sup 3}He neutron detector is highly dependent on the amount of moderator incorporated into the detector system. If there is too little moderation, neutrons will not react with the {sup 3}He. If there is too much moderation, neutrons will not reach the {sup 3}He. In applications for portal or border monitors where {sup 3}He detectors are used to interdict illicit importation of plutonium, the fission source is always shielded to some extent. Since the energy distribution of neutrons emitted from the source depends on the amount and type of shielding present, the optimum placement of moderating material around {sup 3}He tubes is a function of shielding. In this paper, we use Monte Carlo techniques to model the response of {sup 3}He tubes placed in polyethylene boxes for moderation. To model the shielded fission neutron source, we use a point {sup 252}Cf source placed in the center of polyethylene spheres of varying radius. Detector efficiency as a function of box geometry and shielding is explored. We find that increasing the amount of moderator behind and to the sides of the detector generally improves the detector response, but that incremental benefits are minimal if the thickness of the polyethylene moderator is greater than about 5-7 cm. The thickness of the moderator in front of the {sup 3}He tubes, however, is very important. For bare sources, about 4-5 cm of moderator is optimum, but as the shielding increases, the optimum thickness of this moderator decreases to 0.5-1 cm. Similar conclusions can be applied to polyethylene boxes employing two {sup 3}He tubes. Two-tube boxes with front moderators of non-uniform thickness may be useful for detecting neutrons over a wide energy range.

  17. Measurement of indoor radon concentration by CR-39 track detector

    International Nuclear Information System (INIS)

    Yamamoto, Masayoshi; Yoneda, Shigeru; Nakanishi, Takashi.

    1990-01-01

    A convenient and cheap method for measuring indoor radon ( 222 Rn) concentration with a CR-39 track detector is described. The detector consisted of two sheets of CR-39 enclosed separately in two plastic pots : one covered by a filter (cup method) and another no covering (bare method). The bare method was used here to supplement the cup method. To compare with the result of the CR-39 detector, alpha-ray spectrometry was carried out with a Si(Au) detector in a controlled radon exposure chamber. Indoor radon concentration measured in 133 houses in several districts of Ishikawa Prefecture have been found to range from 6 Bq/m 3 to as high as 113 Bq/m 3 with a median value of 24 Bq/m 3 . The problems to measure indoor radon concentration using the CR-39 detector are also discussed with emphasis on the position of setting the detector in the room and the possible thoron contribution to the detector. (author)

  18. Quantitative Identification of the Annealing Degree of Apatite Fission Tracks Using Terahertz Time Domain Spectroscopy (THz-TDS).

    Science.gov (United States)

    Wu, Hang; Wu, Shixiang; Qiu, Nansheng; Chang, Jian; Bao, Rima; Zhang, Xin; Liu, Nian; Liu, Shuai

    2018-01-01

    Apatite fission-track (AFT) analysis, a widely used low-temperature thermochronology method, can provide details of the hydrocarbon generation history of source rocks for use in hydrocarbon exploration. The AFT method is based on the annealing behavior of fission tracks generated by 238 U fission in apatite particles during geological history. Due to the cumbersome experimental steps and high expense, it is imperative to find an efficient and inexpensive technique to determinate the annealing degree of AFT. In this study, on the basis of the ellipsoid configuration of tracks, the track volume fraction model (TVFM) is established and the fission-track volume index is proposed. Furthermore, terahertz time domain spectroscopy (THz-TDS) is used for the first time to identify the variation of the AFT annealing degree of Durango apatite particles heated at 20, 275, 300, 325, 450, and 500 ℃ for 10 h. The THz absorbance of the sample increases with the degree of annealing. In addition, the THz absorption index is exponentially related to annealing temperature and can be used to characterize the fission-track volume index. Terahertz time domain spectroscopy can be an ancillary technique for AFT thermochronological research. More work is urgently needed to extrapolate experimental data to geological conditions.

  19. Scintillating fiber detector performance, detector geometries, trigger, and electronics issues for scintillating fiber tracking

    International Nuclear Information System (INIS)

    Baumbaugh, A.E.

    1994-06-01

    Scintillating Fiber tracking technology has made great advances and has demonstrated great potential for high speed charged particle tracking and triggering. The small detector sizes and fast scintillation fluors available make them very promising for use at high luminosity experiments at today's and tomorrow's colliding and fixed target experiments where high rate capability is essential. This talk will discuss the current state of Scintillating fiber performance and current Visual Light Photon Counter (VLPC) characteristics. The primary topic will be some of the system design and integration issues which should be considered by anyone attempting to design a scintillating fiber tracking system which includes a high speed tracking trigger. Design. constraints placed upon the detector system by the electronics and mechanical sub-systems will be discussed. Seemingly simple and unrelated decisions can have far reaching effects on overall system performance. SDC and DO example system designs will be discussed

  20. International Union of Geological Sciences Subcommission on Geochronology recommendation for the standardization of fission track dating calibration and data reporting

    International Nuclear Information System (INIS)

    Hurford, A.J.

    1990-01-01

    Because of the difficulties of calibration in fission track (FT) dating over the last 20 yr, including uncertainty of the absolute λ f value, complexities of neutron dosimetry, complexities of neutron irradiation, correction factors necessary in some methodological procedures, and personal factors in track counting, the Working Group elected at the Cambridge ICOG meeting in 1986 recommended to FT workers meeting at the 6th International Fission Track Dating Workshop in Besancon on 9 September 1988, a uniform approach to system calibration, sample irradiation, calculation of FT age, and presentation of data. After discussion and modification, the recommendation was accepted. This modified recommendation is presented. (author)

  1. Fission track dating of authigenic quartz in red weathering crusts of carbonate rocks in Guizhou province

    International Nuclear Information System (INIS)

    Liu Xiuming; Wang Shijie; Zhang Feng

    2004-01-01

    The Cenozoic evolution history of Guizhou Province, which is located on the southeastern flank of the Qinghai-Tibet Plateau, is unclear because of the lack of sedimentation records. The red weathering crusts widespread on the Yunnan-Guizhou Plateau may bear critical information about their evolution history. This work firstly determined the ages of four red weathering crusts in eastern, central and northern Guizhou. The material used in fission track dating is well-crystallized quartz occurring in many in-situ weathering crusts of carbonate rocks. The results showed that the fission track ages of quartz vary over a wide range from 1 Ma to 25 Ma in the four profiles, significantly younger than the ages of Triassic and Cambrian parent rocks. In combination with the regionally geological evolution history during the period from 25 Ma to 1 Ma, the ages of quartz can exclude the possibility that the origin of quartz has nothing to do with primary clastic minerals in parent rocks, authigenesis during diagenesis and hydrothermal precipitation or replacement by volcanic activities. It is deduced that the well-crystallized quartz was precipitated from Si-rich weathering fluids during weathering processes of carbonate rocks. The recorded ages of quartz from the four profiles are consistent with the episodes of planation surfaces on the Qinghai-Tibet Plateau, the stages of red soil in the tropics of South China, the tectonically stable periods in Guizhou, and the ages of weathering in other parts of the world during the Cenozoic era. That is to say, the ages of authigenic quartz dated by the fission track method are well feasible and credible. (authors)

  2. Denudation history of the Snowy Mountains: constraints from apatite fission track thermochronology

    International Nuclear Information System (INIS)

    Kohn, B.P.; Gleadow, A.J.W.; Cox, S.J.D.

    1999-01-01

    Apatite fission track thermo chronology from Early Palaeozoic granitoids centred around the Kosciuszko massif of the Snowy Mountains, records a denudation history that was episodic and highly variable. The form of the apatite fission track age profile assembled from vertical sections and hydro-electric tunnels traversing the mountains, together with numerical forward modelling, provide strong evidence for two episodes of accelerated denudation, commencing in Late Permian - Early Triassic (ca 270 250 Ma) and mid-Cretaceous (ca 110-100 Ma) times, and a possible third episode in the Cenozoic. Denudation commencing in the Late Permian - Early Triassic wins widespread in the eastern and Central Snowy Mountains area, continued through much of the Triassic, and amounted to at least ∼2.0-2,4 km. This episode was probably the geomorphic response to the Hunter-Bowen Orogeny. Post-Triassic denudation to the present in these areas amounted to ∼2.0-2.2 km. Unambiguous evidence for mid-Cretaceous cooling and possible later cooling is confined to a north-south-trending sinuous belt, up to ∼15km wide by at least 35km long, of major reactivated Palaeozoic faults on the western side of the mountains. This zone is the most deeply exposed area of the Kosciuszko block. Denudation accompanying these later events totalled up to ∼1.8-2.0 km and ∼2.0 2.25 km respectively. Mid-Cretaceous denudation marks the onset of renewed tectonic activity in the south-eastern highlands following a period of relative quiescence since the Late Triassic, and establishes a temporal link with the onset of extension related to the opening of the Tasman Sea. Much of the present day relief of the mountains resulted from surface uplift which disrupted the post-mid-Cretaceous apatite fission track profile by variable offsets on faults. Copyright (1999) Geological Society of Australia

  3. Determination of trace uranium in atmospheric precipitation of the Xiangjiang river valley by fission track method

    International Nuclear Information System (INIS)

    Zhai Pengji; Kang Tiesheng

    1986-01-01

    In this work the uranium contents in atmospheric precipitations in the region of the Xiangjiang River valley have been measured by fission track method, which range from 0.008 to 1.5 ppb. The majority of them are below 0.1 ppb. The uranium contents in the samples form different geographical positions are obviously different. Sometimes the differences in uranium contents of the samples from the same area collected at different times are also great. A preliminary discussion is given on the sources of uranium in atmospheric precipitation and on the reason of the difference in contents

  4. Experimental study of a methodology for Fission-track Dating without neutron irradiation

    International Nuclear Information System (INIS)

    Hadler, J.C.; Iunes, P.J.; Tello, C.A.; Chemale, F.; Kawashita, K.; Curvo, E.A.C.; Santos, F.G.S.; Gasparini, T.E.; Moreira, P.A.F.P.; Guedes, S.

    2009-01-01

    To carry out the dating by the Fission Track Method (FTM) the international community that works with this method employs methodologies in which the mineral to be dated must be irradiated with neutrons. Such irradiation, performed in a nuclear reactor, demand a relatively long waiting time so that the activity of the sample attain a proper level for handling. The present work aims to establish a methodology that makes possible the dating by FTM using a mass spectrometer instead of a nuclear reactor. This methodology was applied to apatite samples from Durango, Mexico.

  5. Emplacement time of Salai Patai carbonatite, Malakand, Pakistan, from fission track dating of zircon and apatite

    International Nuclear Information System (INIS)

    Qureshi, A.A.; Khan, H.A.

    1991-01-01

    Based on fission track dating of zircon and apatite, the emplacement history of Salai Patai carbonatite has been traced. It has been estimated that the carbonatite was emplaced along the thrust plane associated with the Indian-Eurasian plate collision during the Oligocene period followed by some thermal/tectonic episode during Early Miocene. This negates the previous proposal that all carbonatites found in Pakistan are a part of a 200 km long alkaline province associated with the rifting of Peshawar Valley during Late Cretaceous or early tertiary. (author)

  6. Track based alignment of the Mu3e detector

    Energy Technology Data Exchange (ETDEWEB)

    Hartenstein, Ulrich [Institut fuer Kernphysik, Universitaet Mainz (Germany)

    2016-07-01

    The Mu3e experiment searches for the lepton flavor violating decay μ{sup +} → e{sup +}e{sup -}e{sup +} with a sensitivity goal for the branching fraction of better than 10{sup -16}. This process is heavily supressed in the standard model of particle physics (BR < 10{sup -50}) which makes an observation of this decay a clear indication of new physics. For track reconstruction, four barrel shaped layers consisting of about 3000 high-voltage monolithic active pixel sensors (HV-MAPS) are used. The position, orientation and possible deformations of these sensors must be known to greater precision than the assembly tolerances. A track based alignment via the General Broken Lines fit and the Millepede-II algorithm will be used to achieve this precision in the final detector. The talk discusses a study of the required alignment precision and preparations for aligning the detector using a detailed simulation.

  7. Progress in the development of a tracking transition radiation detector

    International Nuclear Information System (INIS)

    Whitaker, J.S.; Beatty, J.; Shank, J.T.; Wilson, R.J.; Polychronakos, V.A.; Radeka, V.; Stephani, D.; Beker, H.; Bock, R.K.; Botlo, M.; Fabjan, C.W.; Pfennig, J.; Price, M.J.; Willis, W.J.; Akesson, T.; Chernyatin, V.; Dolgoshein, B.; Nevsky, P.; Potekhin, M.; Romanjuk, A.; Sosnovtsev, V.; Gavrilenko, I.; Maiburov, S.; Muravjev, S.; Shmeleva, A.

    1990-01-01

    The purpose of the TRD/Tracker is to provide charged particle tracking in the r-z plane and to provide particle identification capabilities that are independent of and complementary to calorimetric methods. The tracking goals include observation of the charged particle multiplicity and topology, reconstruction of the primary vertex or vertices, and assignment of charged particles to the correct vertex. Particle identification goals include the independent validation of electron candidates selected by calorimetric signatures, the rejection of false electron candidates that rise from accidental overlaps of low momentum charged particles with photon-induced electromagnetic showers in the calorimeter, and the identification of electrons arising from Dalitz decays or from photon conversions. The authors report on progress towards the development of an integrated transition radiation detector and charged particle tracker. Mechanical design and simulation of a detector has been pursued; a prototype device with 240 channels has been constructed and tested. Innovative construction techniques have been developed

  8. Application of nuclear track detectors for radon related measurments

    International Nuclear Information System (INIS)

    Abu-Jarad, F.A.

    1988-01-01

    The application of nuclear track detectors for radon related measurements is discussed. The ''Can Technique'', used for measuring radon emanation from building materials, walls and soil; the ''Working Level Monitor'', used for measuring short period working levels of radon daughters in houses; and ''Passive Radon Dosimeters'', used to measure radon levels in houses for long term (few months) periods are described. Application of nuclear track detectors for measuring the radon daughters plate-out on the surface of mixing fan blades and walls are discussed. The uranium content of some wall papers was found to be 6 ppm. The variation of radon progeny concentration in the same room was measured and supported by another study through Gas Chromatograph measurements. The independence of radon concentration on room level in high-rise buildings was established. The effect of sub-floor radon emanation on radon concentration in houses is dependent on whether there is sub-floor ventilation or not. (author)

  9. Fine grained nuclear emulsion for higher resolution tracking detector

    Energy Technology Data Exchange (ETDEWEB)

    Naka, T., E-mail: naka@flab.phys.nagoya-u.ac.jp [Institute of Advanced Research, Nagoya University, Nagoya (Japan); Asada, T.; Katsuragawa, T.; Hakamata, K.; Yoshimoto, M.; Kuwabara, K.; Nakamura, M.; Sato, O.; Nakano, T. [Graduated School of Science, Nagoya University, Nagoya (Japan); Tawara, Y. [Division of Energy Science, EcoTopia Science Institute, Nagoya University, Nagoya (Japan); De Lellis, G. [INFN Sezione di Napoli, Napoli (Italy); Sirignano, C. [INFN Sezione di Padova, Padova (Italy); D' Ambrossio, N. [INFN, Laboratori Nazionali del Gran Sasso, Assergi (L' Aquila) (Italy)

    2013-08-01

    Fine grained nuclear emulsion with several 10 nm silver halide crystals can detect submicron tracks. This detector is expected to be worked as dark matter detector with directional sensitive. Now, nuclear emulsion became possible to be produced at Nagoya University, and extreme fine grained nuclear emulsion with 20 nm diameter was produced. Using this emulsion and new reading out technique with expansion technique, for optical selection and X-ray microscopy, recoiled tracks induced by dark matter can be detected automatically. Then, readout efficiency is larger than 80% at 120 nm, and angular resolution for final confirmation with X-ray microscopy is 20°. In addition, we started to construct the R and D underground facility in Gran Sasso.

  10. Dilute scintillators for large-volume tracking detectors

    Energy Technology Data Exchange (ETDEWEB)

    Reeder, R.A. (University of New Mexico, Albuquerque, NM (United States)); Dieterle, B.D. (University of New Mexico, Albuquerque, NM (United States)); Gregory, C. (University of New Mexico, Albuquerque, NM (United States)); Schaefer, F. (University of New Mexico, Albuquerque, NM (United States)); Schum, K. (University of New Mexico, Albuquerque, NM (United States)); Strossman, W. (University of California, Riverside, CA (United States)); Smith, D. (Embry-Riddle Aeronautical Univ., Prescott, AZ (United States)); Christofek, L. (Los Alamos National Lab., NM (United States)); Johnston, K. (Los Alamos National Lab., NM (United States)); Louis, W.C. (Los Alamos National Lab., NM (United States)); Schillaci, M. (Los Alamos National Lab., NM (United States)); Volta, M. (Los Alamos National Lab., NM (United States)); White, D.H. (Los Alamos National Lab., NM (United States)); Whitehouse, D. (Los Alamos National Lab., NM (United States)); Albert, M. (University of Pennsylvania, Phi

    1993-10-01

    Dilute scintillation mixtures emit isotropic light for both fast and slow particles, but retain the Cherenkov light cone from fast particles. Large volume detectors using photomultipliers to reconstruct relativistic tracks will also be sensitive to slow particles if they are filled with these mixtures. Our data show that 0.03 g/l of b-PBD in mineral oil has a 2.4:1 ratio (in the first 12 ns) of isotropic light to Cherenkov light for positron tracks. The light attenuation length is greater than 15 m for wavelength above 400 nm, and the scintillation decay time is about 2 ns for the fast component. There is also a slow isotropic light component that is larger (relative to the fast component) for protons than for electrons. This effect allows particle identification by a technique similar to pulse shape discrimination. These features will be utilized in LSND, a neutrino detector at LAMPF. (orig.)

  11. HZE dosimetry in space using plastic track detectors

    CERN Document Server

    Kopp, J; Reitz, G; Enge, W

    1999-01-01

    Plastic nuclear track detectors were used to measure the contribution of High charge Z and energy E (HZE) particles to the radiation exposure of manned space missions. Results from numerous space missions in the orbit planned for the International Space Station are compared. The measurements cover the declining phase of the last solar cycle during the past 7 years and various shielding conditions inside the US Space Shuttle and the Russian MIR-station.

  12. Track fitting in the opal vertex detector with stereo wires

    Energy Technology Data Exchange (ETDEWEB)

    Shally, R; Hemingway, R J; McPherson, A C

    1987-10-01

    The geometry of the vertex chamber for the OPAL detector at LEP is reviewed and expressions for the coordinates of the hits are given in terms of the measured drift distance and z-coordinate. The tracks are fitted by a procedure based on the Lagrange multipliers method. The increase in the accuracy of the fit due to the use of the stereo wires is discussed.

  13. Data acquisition for the Zeus central tracking detector

    International Nuclear Information System (INIS)

    Quinton, S.; Allen, D.; Cambell, D.; Mcarthur, I.

    1990-01-01

    The Zeus experiment is being installed on the Hera electron-proton collider being built at the Desy laboratory in Hamburg. The high-beam crossover rate of the Hera machine will provide experience in data acquisition and triggering relevant to the environment of future accelerators such as the SSC. The Transputer-based data acquisition system for the Zeus central tracking detector is described

  14. Track fitting in the opal vertex detector with stereo wires

    International Nuclear Information System (INIS)

    Shally, R.; Hemingway, R.J.; McPherson, A.C.

    1987-01-01

    The geometry of the vertex chamber for the OPAL detector at LEP is reviewed and expressions for the coordinates of the hits are given in terms of the measured drift distance and z-coordinate. The tracks are fitted by a procedure based on the Lagrange multipliers method. The increase in the accuracy of the fit due to the use of the stereo wires is discussed. (orig.)

  15. A fission ionization detector for neutron flux measurements at a spallation source

    Energy Technology Data Exchange (ETDEWEB)

    Wender, S.A. (Los Alamos National Lab., Los Alamos, NM (United States)); Balestrini, S. (Los Alamos National Lab., Los Alamos, NM (United States)); Brown, A. (Los Alamos National Lab., Los Alamos, NM (United States)); Haight, R.C. (Los Alamos National Lab., Los Alamos, NM (United States)); Laymon, C.M. (Los Alamos National Lab., Los Alamos, NM (United States)); Lee, T.M. (Los Alamos National Lab., Los Alamos, NM (United States)); Lisowski, P.W. (Los Alamos National Lab., Los Alamos, NM (United States)); McCorkle, W. (Los Alamos National Lab., Los Alamos, NM (United States)); Nelson, R.O. (Los Alamos National Lab., Los Alamos, NM (United States)); Parker, W. (Los Alamos National Lab., Los Alamos, NM (United States)); Hill, N.W. (Oak Ridge National Lab., Oak Ridge, TN (United States))

    1993-11-15

    The construction of a neutron flux monitor that can measure absolute neutron intensities in the neutron energy range from below 1 MeV to over 500 MeV is described. The detector consists of an ionization chamber with several thin deposits of fissionable material. The ionization chamber is thin enough that it does not significantly affect the neutron beam and may be left in the neutron flight path during experimental measurements to continuously monitor the beam flux. The use of this monitor at the continuous-energy spallation neutron source at the WNR target area at LAMPF is described. (orig.)

  16. A fission ionization detector for neutron flux measurements at a spallation source

    International Nuclear Information System (INIS)

    Wender, S.A.; Balestrini, S.; Brown, A.; Haight, R.C.; Laymon, C.M.; Lee, T.M.; Lisowski, P.W.; McCorkle, W.; Nelson, R.O.; Parker, W.; Hill, N.W.

    1993-01-01

    The construction of a neutron flux monitor that can measure absolute neutron intensities in the neutron energy range from below 1 MeV to over 500 MeV is described. The detector consists of an ionization chamber with several thin deposits of fissionable material. The ionization chamber is thin enough that it does not significantly affect the neutron beam and may be left in the neutron flight path during experimental measurements to continuously monitor the beam flux. The use of this monitor at the continuous-energy spallation neutron source at the WNR target area at LAMPF is described. (orig.)

  17. Fast neutron detection using solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Vilela, E.C.

    1990-01-01

    CR-39 and Makrofol-E solid state nuclear track detectors were studied aiming their application to fast neutron detection. Optimum etching conditions of those two kinds of materials were determined the followings - the Makrofol-E detector is electrochemically etched in a PEW solution (15% KOH, 40% ethilic alcohol and 45% water) for 2 h., with an applied electric field strength of 30 kV/cm (r/m/s/) and frequency of 2 kHz, at room temperature; - the CR-39 detector is chemically pre-etched during 1 h in a 20% (w/v) NaOH solution at 70 sup(0)C, followed by 13 h electrochemical etch using the same solution at room temperature and an electric field strength of 30 kV/cm (r.m.s.) and frequency of 2 kHz.(E.G.)

  18. Diamond detector time resolution for large angle tracks

    Energy Technology Data Exchange (ETDEWEB)

    Chiodini, G., E-mail: chiodini@le.infn.it [INFN - Sezione di Lecce (Italy); Fiore, G.; Perrino, R. [INFN - Sezione di Lecce (Italy); Pinto, C.; Spagnolo, S. [INFN - Sezione di Lecce (Italy); Dip. di Matematica e Fisica “Ennio De Giorgi”, Uni. del Salento (Italy)

    2015-10-01

    The applications which have stimulated greater interest in diamond sensors are related to detectors close to particle beams, therefore in an environment with high radiation level (beam monitor, luminosity measurement, detection of primary and secondary-interaction vertices). Our aims is to extend the studies performed so far by developing the technical advances needed to prove the competitiveness of this technology in terms of time resolution, with respect to more usual ones, which does not guarantee the required tolerance to a high level of radiation doses. In virtue of these goals, measurements of diamond detector time resolution with tracks incident at different angles are discussed. In particular, preliminary testbeam results obtained with 5 GeV electrons and polycrystalline diamond strip detectors are shown.

  19. Energy-loss measurement with the ZEUS Central Tracking Detector

    Energy Technology Data Exchange (ETDEWEB)

    Bartsch, D.

    2007-05-15

    The measurement of the specific energy loss due to ionisation, dE/dx, in a drift chamber is a very important tool for particle identification in final states of reactions between high energetic particles. Such identification requires a well understood dE/dx measurement including a precise knowledge of its uncertainties. Exploiting for the first time the full set of ZEUS data from the HERA operation between 1996 and 2005 twelve detector-related influences affecting the dE/dx measurement of the ZEUS Central Tracking Detector have been identified, separately studied and parameterised. A sophisticated iterative procedure has been developed to correct for these twelve effects, which takes into account the correlations between them. A universal parameterisation of the detector-specific Bethe-Bloch curve valid for all particle species has been extracted. In addition, the various contributions to the measurement uncertainty have been disentangled and determined. This yields the best achievable prediction for the single-track dE/dx resolution. For both the analysis of the measured data and the simulation of detector performance, the detailed understanding of the measurement and resolution of dE/dx gained in this work provides a tool with optimum power for particle identification in a physics studies. (orig.)

  20. Energy-loss measurement with the ZEUS Central Tracking Detector

    International Nuclear Information System (INIS)

    Bartsch, D.

    2007-05-01

    The measurement of the specific energy loss due to ionisation, dE/dx, in a drift chamber is a very important tool for particle identification in final states of reactions between high energetic particles. Such identification requires a well understood dE/dx measurement including a precise knowledge of its uncertainties. Exploiting for the first time the full set of ZEUS data from the HERA operation between 1996 and 2005 twelve detector-related influences affecting the dE/dx measurement of the ZEUS Central Tracking Detector have been identified, separately studied and parameterised. A sophisticated iterative procedure has been developed to correct for these twelve effects, which takes into account the correlations between them. A universal parameterisation of the detector-specific Bethe-Bloch curve valid for all particle species has been extracted. In addition, the various contributions to the measurement uncertainty have been disentangled and determined. This yields the best achievable prediction for the single-track dE/dx resolution. For both the analysis of the measured data and the simulation of detector performance, the detailed understanding of the measurement and resolution of dE/dx gained in this work provides a tool with optimum power for particle identification in a physics studies. (orig.)

  1. New approaches in fission track geochronology as a tectonic tool: examples from the Transantarctic Mountains

    International Nuclear Information System (INIS)

    Fitzgerald, P.G.

    1990-01-01

    Apatite fission track analysis has been applied to study the uplift history and tectonics of the Transantarctic Mountains. An uplifted fossil apatite annealing zone has been identified in the apatite age vs elevation profile and is confirmed by track length data. A ''break in slope'' in the apatite age profile marks the base of the uplifted partial annealing zone and approximates the time of initiation of uplift of the mountains. Samples below the ''break in slope'' give information on the rate(s) of uplift. Samples above the break have apatite ages that vary significantly with elevation, but the gradient is not equal to an apparent uplift rate. Rather, it is due to inherited characteristics from the pre-existing partial annealing zone. These samples above the ''break in slope'' can be used as indicators of paleo-depth in the pre-uplift crust to determine the structure of an area and the displacement across faults. (author)

  2. Fast simulation of the forward tracking detector of HPLUS

    International Nuclear Information System (INIS)

    Zhang Yapeng; Fan Ruirui; Fu Fen; Yue Ke; Yuan Xiaohua; Xu Huagen; Chinese Academy of Sciences, Beijing; Yao Nan; Xu Hushan; Jin Genming; Liang Jinjie; Chen Ruofu; Sun Zhiyu; Duan Limin; Xiao Zhigang; Tsinghua Univ., Beijing

    2008-01-01

    The necessity of installing a forward tracking detector stack is discussed for the Hadron Physics Lanzhou Spectrometer(HPLUS). A local tracker is developed to solve the multi-track finding problem. The track candidates are searched iteratively via Hough Transform. The fake tracks are removed by a least square fitting process. With this tracker we have studied the feasibility of pp→pp+φ(→K + K - ), a typical physical channel proposed on HPLUS. The single track momentum resolution due to the uncertainty of the positioning in FTD is 1.3%. The multiple scattering effect contributes about 20% to the momentum resolution in the FTD coverage. The width and the signal-to-background ratio of the reconstructed φ are 1.51 MeV and 4.36, respectively, taking into account the direct Kaon channel pp→pp+K + K - as background. The geometry coverage of FTD for qb events is about 85.4%. Based on the current fast simulation and estimation, the geometrical configuration of FTD meets the physical requirement of HPLUS under the current luminosity and multiplicity conditions. The tracker is applicable in the full simulation coming next and is extendable to other tracking component of HPLUS. (authors)

  3. The Comparison Study of Neutron Activation Analysis and Fission Track Technique for Uranium Determination

    International Nuclear Information System (INIS)

    Sirinuntavid, Alice; Rodthongkom, Chouvana

    2007-08-01

    Full text: Comparison between Neutron Activation Analysis (NAA) and fission track technique for uranium determination in solid samples was studied by use of standard reference materials, i.e., ore, coal fly ash, soil. For NAA, the epithermal neutron was applied for activated irradiation. Then, the 74.5 keV gamma from U-239 or 277.7 keV gamma from Np-239 was measured. For high Uranium content samples, NAA method with 74.5 keV gamma measurement, gave higher precision result than the 277.7 keV gamma measurement method. NAA method with 277.7 keV gamma measurement, gave higher sensitivity and precision result for low Uranium content samples and the uranium contained less than 10 ppm samples. Nevertheless, the latter procedure needed longer time for neutron irradiation and analysis procedure. In comparison the results of Uranium analysis between NAA and fission track, it was found that no significant difference within 95 % of confidence level

  4. Fission track dating of tuffaceous eocene formations of the North Bakony Mountains (Transdanubia, Hungary)

    International Nuclear Information System (INIS)

    Dunkl, I.

    1990-01-01

    Fission track dating was performed in accessory minerals of strongly altered, clay mineralized tuffite strata lying in the upper part of the Eocene sequence of the North Bakony Mountains. The homogeneity of the fission track (FT) ages measured on apatite and zircon refers only to insignificant redeposition, no remarkable mingling of the detrital matter vould be stated. The average of the FT-ages falls to the Bartonian, into the time interval determined by nannoplankton guide horizons for the volcanic activity (41.9 ± 4.1 Ma). As to their biostratigraphic age the Middle Eocene samples show an FT-average of 44.2 ± 3.4 Ma, the average of the Upper Eocene group is 39.9 ± 4.1 Ma. The difference between the two groups refers to the two phases of the volcanic activity. The first maximum of volcanism generated the Upper Lutetian to Bartonian glauconitic sequence while the second maximum at the Bartonian-Priabonian boundary produced the tuff strata. The strata in the neighbouring areas relate to continuous volcanism in the Upper Eocene, in the studied area, however, the upper part of the Priabonian was eroded. (author) 51 refs.; 4 figs.; 1 tab

  5. Mass distribution of fission fragments using SSNTDs based image analysis system

    International Nuclear Information System (INIS)

    Kolekar, R.V.; Sharma, D.N.

    2006-01-01

    Lexan polycarbonate track detector was used to obtain mass distribution of fission fragments from 252 Cf planchette source, Normally, if the fission fragments are incident perpendicular to the lexan surface, the diameter of heavy fragment is greater than that of lighter fragment. In practical problems fission fragments are incident on the detector at all angles. So, in the present experiment, lexan detector was exposed to 252 Cf planchette source in 2π geometry. Fission fragments were incident on the detector with various angles. So the projected fission track length for fission fragment of same energy is different because of different angle of incidence. Image analysis software was used to measure the projected track length. But the problem is that for fission fragment having greater angle of incidence the entire track length is not focused on the surface. So reduced track length is measured. This problem is solved by taking two images, one at the surface and one at the tip of track and then overlapping both the images using image analysis software. The projected track length and the depth of the track were used to get the angle of incidence. Fission track lengths were measured for same angle of incidence. In all 500 track lengths were measured and plot for mass distribution for fission fragment was obtained.(author)

  6. Calculation of depleted uranium concentration in dental fillings samples using the nuclear track detector CR-39

    International Nuclear Information System (INIS)

    Mahdi, K. H.; Subhi, A. T.; Tawfiq, N. F.

    2012-12-01

    The purpose of this study is to determine the concentration of depleted uranium in dental fillings samples, which were obtained some hospital and dental office, sale of materials deployed in Iraq. 8 samples were examined from two different fillings and lead-filling (amalgam) and composite filling (plastic). concentrations of depleted uranium were determined in these samples using a nuclear track detector CR-39 through the recording of the tracks left by of fragments of fission resulting from the reaction 2 38U (n, f). The samples are bombarded by neutrons emitted from the neutron source (2 41A m-Be) with flux of ( 10 5 n. cm- 2. s -1 ). The period of etching to show the track of fission fragments is 5 hours using NaOH solution with normalization (6.25N), and temperature (60 o C ). Concentration of depleted uranium were calculated by comparison with standard samples. The result that obtained showed that the value of the weighted average for concentration of uranium in the samples fillings (5.54± 1.05) ppm lead to thr filling (amalgam) and (5.33±0.6) ppm of the filling composite (plastic). The hazard- index, the absorbed dose and the effective dose for these concentration were determined. The obtained results of the effective dose for each of the surface of the bone and skin (as the areas most affected by this compensation industrial) is (0.56 mSv / y) for the batting lead (amalgam) and (0.54 mSv / y) for the filling composite (plastic). From the results of study it was that the highest rate is the effective dose to a specimen amalgam filling (0.68 mSv / y) which is less than the allowable limit for exposure of the general people set the World Health Organization (WHO), a (1 mSv / y). (Author)

  7. Mass dependence of positive pion-induced fission

    International Nuclear Information System (INIS)

    Khan, H.A.; Khan, N.A.; Peterson, R.J.

    1991-01-01

    Fission cross sections for a range of targets have been measured by solid-state track detectors following 80 and 100 MeV π + bombardment. Fission probabilities have been inferred by comparison to computed reaction cross sections. Fission probabilities for heavy targets agree with those for other probes of comparable energy and with statistical calculations. Probabilities for lighter targets are much above those previously observed or computed. Ternary fission cross sections and multiplicities of light fragments have also been determined

  8. The dielectric track and thermoluminescent detectors applied to neutron dosimetry in personnel monitoring

    International Nuclear Information System (INIS)

    Mebhah, D.

    1984-03-01

    The personnal dosimeter for neutron based on the detection of fission fragments from 237 Np and 232 Th by a polycarbonate 10 gm, and lithium fluorite 6 LIF/ 7 LIF, allow to cover an energy spectrum from 0.05 eV to 14 MeV with a easy neutron gamma discrimination. In criticality dosimetry, the energy spectrum of the incident neutrons can be defined by two components: the fast component by E b exp(-ae) with E between 0.1 and 14 MeV, a and b determined by a combination of 237 Np and 232 Th track detector responses, and the epithermal component in 1/E, the thermal component having a minor contribution to the total equivalent dose. We took into account the body influence on the detectors response by introducing effective cross section. The equivalent dose obtained by this dosimeter is 20% overestimated in low doses dosimetry. The interpretation of the detectors responses is based on the definition of a factor and a calibration parameter for each zone in which the spectrum is constant. The knowledge of this parameter for individual dosimeters allows to account for the variations of the conditions of calibration

  9. Study of the temperature effect on the surface of stainless steel using fission track technique

    Energy Technology Data Exchange (ETDEWEB)

    Dhawan, M M; Nagpaul, K K [Kurukshetra Univ. (India). Dept. of Physics

    1977-01-01

    Solid state track technique has been used to determine trace amounts of uranium in steel. Steel samples of the size 1 cm x 1 cm x 0.6 cm were ground, polished, heated to various temperatures ranging from room temperature to 900 deg C and then packed alternately with lexan detectors in an aluminium capsule for thermal neutron irradiation. After irradiation, lexan discs were removed and etched. Their surfaces were scanned under an optical microscope for measurement of track density. Uranium contents of the samples was found to vary from 6 ppm to 9 ppm.

  10. The measurement of the uranium content of crystals, glasses and meteorites with the fission track method

    International Nuclear Information System (INIS)

    Vartanian, R.

    1977-04-01

    In the present investigation, work has been carried out regarding the measurement of the uranium content of minerals, crystals and meteoritic samples from different parts of Iran. In this paper the method of inducing tracks from the 235 U indigenous to the Solid State Nuclear Track Detectors (SSNTDS) is described and new results have been attained. These are summarized as follows: Apatite between (4.16+-0.27) and (10.54+-0.84) ppm, Wulfnite=(4.90+-0.37) ppm, Quartz=(0.15+-0.02) ppm and Meteorite=(0.026+-0.003) ppm. (author)

  11. Interaction of 84 MeV/u 12C with 208Pb target investigated with CR-39 plastic track detector

    International Nuclear Information System (INIS)

    Grabez, B.

    1984-01-01

    The interaction of the 84 MeV/u 12 C ions with 208 Pb target was investigated using CR-39 plastic track detector. The first part of the work was dedicated to the examination of the methodology of the recently presented CR-39 detector and its calibration. Measurements have been done on tracks of various ions in the broad atomic number region from Z = 2 to Z = 92. The possibility of the identification of low energy fragments produced in nuclear interactions by measurements on the finished tracks was studied. Our results show that very good charge resolution can be achieved through determination of the mean etch rate ratio and the range of low energy ions. In the second part of the work it was shown that the main reaction channels in the interaction of 84 MeV/u C with Pb target are spallation, fission and fragmentation. The contribution of the multifragmentation is less than 1% of the total reaction cross section. From our results follows that the most probable reaction channels after collision with small impact parameter are fragmentation and deep spallation. The spallation and fission come after more peripheral collisions. (orig./HSI)

  12. Fabrication and Testing of a Modular Micro-Pocket Fission Detector Instrumentation System for Test Nuclear Reactors

    Science.gov (United States)

    Reichenberger, Michael A.; Nichols, Daniel M.; Stevenson, Sarah R.; Swope, Tanner M.; Hilger, Caden W.; Roberts, Jeremy A.; Unruh, Troy C.; McGregor, Douglas S.

    2018-01-01

    Advancements in nuclear reactor core modeling and computational capability have encouraged further development of in-core neutron sensors. Measurement of the neutron-flux distribution within the reactor core provides a more complete understanding of the operating conditions in the reactor than typical ex-core sensors. Micro-Pocket Fission Detectors have been developed and tested previously but have been limited to single-node operation and have utilized highly specialized designs. The development of a widely deployable, multi-node Micro-Pocket Fission Detector assembly will enhance nuclear research capabilities. A modular, four-node Micro-Pocket Fission Detector array was designed, fabricated, and tested at Kansas State University. The array was constructed from materials that do not significantly perturb the neutron flux in the reactor core. All four sensor nodes were equally spaced axially in the array to span the fuel-region of the reactor core. The array was filled with neon gas, serving as an ionization medium in the small cavities of the Micro-Pocket Fission Detectors. The modular design of the instrument facilitates the testing and deployment of numerous sensor arrays. The unified design drastically improved device ruggedness and simplified construction from previous designs. Five 8-mm penetrations in the upper grid plate of the Kansas State University TRIGA Mk. II research nuclear reactor were utilized to deploy the array between fuel elements in the core. The Micro-Pocket Fission Detector array was coupled to an electronic support system which has been specially developed to support pulse-mode operation. The Micro-Pocket Fission Detector array composed of four sensors was used to monitor local neutron flux at a constant reactor power of 100 kWth at different axial locations simultaneously. The array was positioned at five different radial locations within the core to emulate the deployment of multiple arrays and develop a 2-dimensional measurement of

  13. Building a tracking detector for the P2 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Zimmermann, Marco [Institute of Nuclear Physics, Johannes Gutenberg University, Mainz (Germany); PRISMA Cluster of Excellence (Germany); Collaboration: P2-Collaboration

    2016-07-01

    The P2 Experiment aims to measure the weak mixing angle at low Q{sup 2} via the parity violating asymmetry in elastic electron-proton scattering. It will be located at the new Mainz Energy Recovery Superconducting Accelerator (MESA), which will provide a 150 μA beam of alternatingly polarized 150 MeV electrons. While the main asymmetry measurement is performed with integrating Cherenkov detectors, the tracking system is developed in order to determine the average momentum transfer of the electron and to reconstruct individual electron tracks for systematic studies. It will be built using the new technology of High Voltage Monolithic Active Pixel Sensors (HV-MAPS) made of silicon thinned to 50 μm. The main challenge for the tracking system are very high expected particle rates. The expected rate of electrons that are scattered in the liquid hydrogen target and hit the tracking system is of the order 10{sup 5}mm{sup -2}s{sup -1} and is overwhelmed by more than 10{sup 7} mm{sup -2}s{sup -1} bremsstrahlung photons. Each of the tracking layers is envisaged to have a disc-like geometry. They are arranged as two double layers. Since only limited sensor area is affordable, each layer is divided into four segments with about 15 degree azimutal coverage. This layout is presented and motivated by investigations on the expected hit rates and the sensor response.

  14. Thermal flow in detectors of CNA-II with spontaneous fissions source of 238U

    International Nuclear Information System (INIS)

    Mascitti, J. A

    2012-01-01

    The thermal flux in the position of ex-core and in-core CNA-II Nuclear Power Plant (CNA-II) detectors is estimated considering neutron from the 238 U spontaneous fissions as the source, for the reactor cold state (isothermal state with both coolant and moderator at a temperature of 60 o C, a pressure of 35 ata and 15.46 ppm of natural Boron), and 24% inserted control rods (slightly sub-critical). Results are obtained for two different situations: with and without photo-neutrons due to the (γ,n) reaction in D 2 O. It is concluded that the thermal flux is under the detection limit of the boron trifluoride 104-SR or 282-IB detectors (≅10 -1 cm-2.s -1 ). These detectors are located in opposite positions in the inner concrete shielding, having the lowest detection limit among all ex-core detectors. A significant difference is verified in neutron fluxes between both cases, which suggest that photo-neutrons in large heavy water reactors such as CNA-II should not be ignored. The total neutron flux attenuation factor between the inner and outer region of the reactor pressure vessel was estimated to be 7.0 x 10 -7 . It should be mentioned that none of the results here presented has been affected by any correction factor. Each value has a percentage relative error representing the statistical uncertainty due to the probabilistic Monte Carlo method used to obtain it (author)

  15. Feasibility studies for a wireless 60 GHz tracking detector readout

    International Nuclear Information System (INIS)

    Dittmeier, S.; Schöning, A.; Soltveit, H.K.; Wiedner, D.

    2016-01-01

    The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the integration of the wireless technology at 60 GHz into a silicon tracking detector. We use spare silicon strip modules of the ATLAS experiment as test samples which are measured to be opaque in the 60 GHz range. The reduction of cross talk between links and the attenuation of reflections is studied. An estimate of the maximum achievable link density is given. It is shown that wireless links can be placed as close as 2 cm next to each other for a layer distance of 10 cm by exploiting one or several of the following measures: highly directive antennas, absorbers like graphite foam, linear polarization and frequency channeling. Combining these measures, a data rate area density of up to 11 Tb/(s·m"2) seems feasible. In addition, two types of silicon sensors are tested under mm-wave irradiation in order to determine the influence of 60 GHz data transmission on the detector performance: an ATLAS silicon strip sensor module and an HV-MAPS prototype for the Mu3e

  16. Feasibility studies for a wireless 60 GHz tracking detector readout

    Energy Technology Data Exchange (ETDEWEB)

    Dittmeier, S., E-mail: dittmeier@physi.uni-heidelberg.de; Schöning, A.; Soltveit, H.K.; Wiedner, D.

    2016-09-11

    The amount of data produced by highly granular silicon tracking detectors in high energy physics experiments poses a major challenge to readout systems. At high collision rates, e.g. at LHC experiments, only a small fraction of data can be read out with currently used technologies. To cope with the requirements of future or upgraded experiments new data transfer techniques are required which offer high data rates at low power and low material budget. Wireless technologies operating in the 60 GHz band or at higher frequencies offer high data rates and are thus a promising upcoming alternative to conventional data transmission via electrical cables or optical fibers. Using wireless technology, the amount of cables and connectors in detectors can be significantly reduced. Tracking detectors profit most from a reduced material budget as fewer secondary particle interactions (multiple Coulomb scattering, energy loss, etc.) improve the tracking performance in general. We present feasibility studies regarding the integration of the wireless technology at 60 GHz into a silicon tracking detector. We use spare silicon strip modules of the ATLAS experiment as test samples which are measured to be opaque in the 60 GHz range. The reduction of cross talk between links and the attenuation of reflections is studied. An estimate of the maximum achievable link density is given. It is shown that wireless links can be placed as close as 2 cm next to each other for a layer distance of 10 cm by exploiting one or several of the following measures: highly directive antennas, absorbers like graphite foam, linear polarization and frequency channeling. Combining these measures, a data rate area density of up to 11 Tb/(s·m{sup 2}) seems feasible. In addition, two types of silicon sensors are tested under mm-wave irradiation in order to determine the influence of 60 GHz data transmission on the detector performance: an ATLAS silicon strip sensor module and an HV-MAPS prototype for the Mu3e

  17. The obsidian from Quiron (Salta Province, Argentina): a new reference glass for fission-track dating

    Energy Technology Data Exchange (ETDEWEB)

    Bigazzi, G. [Istituto di Geoscienze e Georisorse, C.N.R., Area della Ricerca di Pisa, V.G. Moruzzi, 1, 56124 Pisa (Italy)]. E-mail: g.bigazzi@igg.cnr.it; Laurenzi, M.A. [Istituto di Geoscienze e Georisorse, C.N.R., Area della Ricerca di Pisa, V.G. Moruzzi, 1, 56124 Pisa (Italy); Viramonte, J.G. [Instituto Geonorte, Universidad Nacional de Salta and Conicet, Buenos Aires 177, 4400 Salta (Argentina)

    2005-12-01

    In the course of a geochronological study of the volcanic activity in the Andean Cordillera in northern Argentina, we have found in the El Quevar volcanic complex (24 deg. 19{sup '}S/66 deg. 43{sup '}W,6180m) a phenocryst poor obsidian (Quiron obsidian) showing an unusually high spontaneous track density. Defects which might produce 'spurious' tracks are virtually absent. Application of fission-track dating using an absolute approach, based on the IRMM-540 standard glass for neutron fluence measurements, yielded an apparent age of 7.27+/-0.29Ma(1{sigma}) and a plateau age of 8.99+/-0.31Ma(1{sigma}). A {sup 40}Ar-{sup 39}Ar isochron age on biotite of 8.61+/-0.04Ma(1{sigma}) was already available for the Quiron rhyolite. We determined further {sup 40}Ar-{sup 39}Ar ages on several chips of the glass itself using two analytical approaches: total fusion with a focussed laser beam (LTFA) and a step-heating approach using a de-focussed laser beam (LSHA). We have obtained a weighted average of 8.77+/-0.09Ma, an isochron age of 8.71+/-0.12Ma and an integrated age of 8.77+/-0.09Ma for LTF analyses, and a w.a. of 8.75+/-0.09Ma, an iso.a. of 8.77+/-0.09Ma and an int.a. of 8.77+/-0.09Ma for LSH analyses (all age errors are 2{sigma}). The Quiron obsidian is very easy to analyse for its high spontaneous track density and because microlites which might produce spurious tracks are very rare. Independent reference {sup 40}Ar-{sup 39}Ar ages determined in different laboratories are available. For these reasons we believe that this glass may be very useful for testing fission-track system calibrations and apparent age correction procedures. Splits of obsidian Quiron will be distributed upon request to colleagues who intend to test it.

  18. A new method for determining the uranium and thorium distribution in volcanic rock samples using solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Misdaq, M.A.; Bakhchi, A.; Ktata, A.; Koutit, A.; Lamine, J.; Ait nouh, F.; Oufni, L.

    2000-01-01

    A method based on using solid state nuclear track detectors (SSNTD) CR- 39 and LR-115 type II and calculating the probabilities for the alpha particles emitted by the uranium and thorium series to reach and be registered on these films was utilized for uranium and thorium contents determination in various geological samples. The distribution of uranium and thorium in different volcanic rocks has been investigated using the track fission method. In this work, the uranium and thorium contents have been determined in different volcanic rock samples by using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTD). The mean critical angles of etching of the solid state nuclear track detectors utilized have been calculated. A petrographical study of the volcanic rock thin layers studied has been conducted. The uranium and thorium distribution inside different rock thin layers has been studied. The mechanism of inclusion of the uranium and thorium nuclei inside the volcanic rock samples studied has been investigated. (author)

  19. Geology and zircon fission track ages of volcanic rocks in the western part of Hoshino gold area, Fukuoka Prefecture, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Belhadi, Ahmed; Himeno, Osamu; Watanabe, Koichiro; Izawa, Eiji [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering

    1999-12-01

    The Hoshino gold area is located in the western part of the Hohi volcanic zone, northern Kyushu. Volcanic rocks in this area vary from andesitic rocks in the north to dacite and rhyolite in the South. The basement is constituted by metamorphic rocks of pre-Cretaceous age. The volcanic rocks of Pliocene age were subdivided into eight volcanic units. Seven fission track ages of zircons from five volcanic units have been determined, using the external detector method. The age data obtained, combined with some previously reported ages, show that two main volcanic activities have occurred in the area. The first volcanic activity took place around 4.3 Ma, and resulted into the deposition of the Hoshino Andesite and the Ikenoyama Conglomerate. The second main volcanism started around 3.5 Ma, and was characterized by the eruption of the Shakadake Andesite and the Reiganji Andesite at the early stage, then, by more acidic rocks of the Takeyama Andesite, the Hyugami Dacite and the Kuroki Rhyolite at the later stage. The main volcanism in the area ceased around 2.6 Ma. (author)

  20. Estimation of track registration efficiency in solution medium and study of gamma irradiation effects on the bulk-etch rate and the activation energy for bulk etching of CR-39 (DOP) Solid State Nuclear Track Detector

    International Nuclear Information System (INIS)

    Kalsi, P.C.

    2010-01-01

    The fission track registration efficiency of diethylene glycol bis allyl carbonate (dioctyl phthalate doped) (CR-39 (DOP)) solid state nuclear track detector (SSNTD) in solution medium (K wet ) has been experimentally determined and is found to be (9.7 ± 0.5).10 -4 cm. This is in good agreement with the values of other SSNTDs. The gamma irradiation effects in the dose range of 50.0-220.0 kGy on the bulk etch rate, V b and the activation energy for bulk etching, E of this solid state nuclear track detector (SSNTD) have also been studied. It is observed that the bulk etch rates increase and the activation energies for bulk etching decrease with the increase in gamma dose. These results have been explained on the basis of scission of the detector due to gamma irradiation

  1. Compton recoil electron tracking with silicon strip detectors

    International Nuclear Information System (INIS)

    O'Neill, T.J.; Ait-Ouamer, F.; Schwartz, I.; Tumer, O.T.; White, R.S.; Zych, A.D.

    1992-01-01

    The application of silicon strip detectors to Compton gamma ray astronomy telescopes is described in this paper. The Silicon Compton Recoil Telescope (SCRT) tracks Compton recoil electrons in silicon strip converters to provide a unique direction for Compton scattered gamma rays above 1 MeV. With strip detectors of modest positional and energy resolutions of 1 mm FWHM and 3% at 662 keV, respectively, 'true imaging' can be achieved to provide an order of magnitude improvement in sensitivity to 1.6 x 10 - 6 γ/cm 2 -s at 2 MeV. The results of extensive Monte Carlo calculations of recoil electrons traversing multiple layers of 200 micron silicon wafers are presented. Multiple Coulomb scattering of the recoil electron in the silicon wafer of the Compton interaction and the next adjacent wafer is the basic limitation to determining the electron's initial direction

  2. Tracking performance of the ATLAS inner detector and observation of known hadrons

    NARCIS (Netherlands)

    Kayl, M.; Trischuk, W.

    2010-01-01

    The inner detector is the central tracking device of the ATLAS detector. In these proceedings the tracking performance of the inner detector is presented on collision data recorded at $\\sqrt{s}$ = 900 GeV and 7 TeV. The identification of resonances like $\\Xi$ and $\\Omega$ baryons in cascade decays

  3. CMS detector tracking performance in Run-II

    CERN Document Server

    Brondolin, Erica

    2017-01-01

    Since the start of Run-II in June 2015, LHC has delivered pp collisions at a center of mass energy of 13TeV and with a bunch time separation of 25 ns. On avarage, more than 25 inelastic collisions are superimposed on the event of interest. Under these new conditions, the CMS collaboration has re-calibrated and verified the performance of the whole detector. In particular, the CMS tracking performance has been measured both directly and indirectly. Direct measurements are, among others, the beam spot determination, the vertex resolution and the muon reconstruction efficiency with the tag and probe technique. An indirect assessment can be given by the pion reconstruction efficiency and the low-mass resonance parameters as a function of different single track kinematics.

  4. A passive monitor for radon using electrochemical track etch detector

    International Nuclear Information System (INIS)

    Massera, G.E.; Hassib, G.M.; Piesch, E.

    1980-01-01

    A passive, inexpensive monitor for radon detection and dosimetry is described in detail. It consists of a Makrofoil track etch detector inside a diffusion chamber which is sealed by a fibreglass filter through which radon may diffuse while radon daughters and aerosols are retained on the surface of the filter. The α-particle tracks are revealed by etching the Makrofoil in KOH. The lower detection limit of the radon dosimeter is equivalent to a mean dose in the lung of 130 mrem. After an exposure period of 3 months, a mean radon concentration of 0.3 pCi/l can be detected. The instrument is intended for use in a study to measure the long-term radon exposure in buildings in West Germany. (UK)

  5. Track reconstruction in discrete detectors by neutral networks

    Energy Technology Data Exchange (ETDEWEB)

    Glazov, A A; Kisel` , I V; Konotopskaya, E V; Neskoromnyj, V N; Ososkov, G A

    1993-12-31

    On the basis of applying neutral networks to the track recognition problem the investigations are made according to the specific properties of such discrete detectors as multiwire proportional chambers. These investigations result in the modification of the so-called rotor model in a neutral neural network. The energy function of a network in this modification contains only one cost term. This speeds up calculations considerably. The reduction of the energy function is done by the neuron selection with the help of simplegeometrical and energetical criteria. Besides, the cellular automata were applied to preliminary selection of data that made it possible to create an initial network configuration with the energy closer to its global minimum. The algorithm was tested on 10{sup 4} real three-prong events obtained from the ARES-spectrometer. The results are satisfactory including the noise robustness and good resolution of nearby going tracks. 12 refs.; 10 figs.

  6. Track reconstruction in discrete detectors by neutral networks

    International Nuclear Information System (INIS)

    Glazov, A.A.; Kisel', I.V.; Konotopskaya, E.V.; Neskoromnyj, V.N.; Ososkov, G.A.

    1992-01-01

    On the basis of applying neutral networks to the track recognition problem the investigations are made according to the specific properties of such discrete detectors as multiwire proportional chambers. These investigations result in the modification of the so-called rotor model in a neutral neural network. The energy function of a network in this modification contains only one cost term. This speeds up calculations considerably. The reduction of the energy function is done by the neuron selection with the help of simplegeometrical and energetical criteria. Besides, the cellular automata were applied to preliminary selection of data that made it possible to create an initial network configuration with the energy closer to its global minimum. The algorithm was tested on 10 4 real three-prong events obtained from the ARES-spectrometer. The results are satisfactory including the noise robustness and good resolution of nearby going tracks. 12 refs.; 10 figs

  7. UV-irradiation effects on polyester nuclear track detector

    International Nuclear Information System (INIS)

    Agarwal, Chhavi; Kalsi, P.C.

    2010-01-01

    The effects of UV irradiation (λ=254 nm) on polyester nuclear track detector have been investigated employing bulk-etch technique, UV-visible spectrophotometry and infra-red spectrometry (FTIR). The activation energy values for bulk-etching were found to decrease with the UV-irradiation time indicating the scission of the polymer. Not much shift in the absorption edge due to UV irradiation was seen in the UV-visible spectra. FTIR studies also indicate the scission of the chemical bonds, thereby further validating the bulk-etch rate results.

  8. Measurements of radon in dwellings with CR-39 track detectors

    DEFF Research Database (Denmark)

    Majborn, Benny

    1986-01-01

    A passive integrating dosemeter has been designed for measuring natural radiation in dwellings. The dosemeter contains one or two CR-39 track detectors to measure radon and three thermoluminescence dosemeters to measure external radiation. The dosemeter was investigated in a pilot study in 1983....../84, and it is now used in a nationwide survey of natural radiation in Danish dwellings. The characteristics of the dosemeter with respect to radon measurements are presented, and the radon monitoring results obtained in the pilot study are summarized...

  9. Charged particle spectroscopy with solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Hunyadi, I.; Somogyi, G.

    1984-01-01

    Some of earlier and recent methods for differentiation of charged particles according to their energy, based on the use of polymeric etch-track detectors (CN, CA, PC and CR-39) are outlined. The principle of three track methods suitable for nuclear spectroscopy is discussed. These are based on the analysis of the diameter, surface size and shape of etch-track 'cones' produced by charged particles in polymers, after using shorter or longer chemical etching processes. Examples are presented from the results of the last decade in ATOMKI, Debrecen, Hungary, concerning the application of nuclear track spectroscopy to different low-energy nuclear reaction studies, angular distribution and excitation function measurements. These involve the study of (d,α) reaction on sup(14)N, sup(19)F and sup(27)Al nuclei, (sup(3)He,α) reactions on sup(15)N, (p,α) reaction on sup(27)Al and the process sup(12)C(sup(12)C, sup(8)Be)sup(16)O. (author)

  10. Nuclear track detectors for charged particles and neutrons

    International Nuclear Information System (INIS)

    Tommasino, L.

    2006-01-01

    It was with great emotion that I accepted to be a guest speaker to this memorial section dedicated to my old-time friend, Prof. Radomir Ilic. In addition to being one of the most outstanding scientists in the field of nuclear tracks, Prof. Radomir Ilic has been always highly acclaimed by the scientific community for his enthusiasm, his warm friendship, and his great vitality. Through his successful editorial activities, Prof. Ilic has proved to be very able to address the field of nuclear tracks to very wide audiences with special regards to young students. It was here in Portoroz, that Prof. Radomir Ilic was our host as the organiser of the 21st International Conference on Nuclear Tracks in Solids. All the participants have great memories of this very successful international conference. For all these reasons, the 2006 edition of the International Conference on Nuclear Energy for new Europe, with its wide audience and its venue at Portoroz, can be considered as one of the most appropriate forum for the memorial lecture of Prof. Radomir Ilic. The present paper will be dealing with the solid state nuclear track detectors-SSNTDs and their successful applications for the measurements of cosmic-ray-neutrons and terrestrial radioactivity, namely radon. (author)

  11. NEET Enhanced Micro Pocket Fission Detector for High Temperature Reactors - FY15 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Unruh, Troy [Idaho National Lab. (INL), Idaho Falls, ID (United States); McGregor, Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ugorowski, Phil [Idaho National Lab. (INL), Idaho Falls, ID (United States); Reichenberger, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ito, Takashi [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    A new project, that is a collaboration between the Idaho National Laboratory (INL), the Kansas State University (KSU), and the French Atomic Energy Agency, Commissariat à l'Énergie Atomique et aux Energies Alternatives, (CEA), has been initiated by the Nuclear Energy Enabling Technologies (NEET) Advanced Sensors and Instrumentation (ASI) program for developing and testing High Temperature Micro-Pocket Fission Detectors (HT MPFD), which are compact fission chambers capable of simultaneously measuring thermal neutron flux, fast neutron flux and temperature within a single package for temperatures up to 800 °C. The MPFD technology utilizes a small, multi-purpose, robust, in-core parallel plate fission chamber and thermocouple. As discussed within this report, the small size, variable sensitivity, and increased accuracy of the MPFD technology represent a revolutionary improvement over current methods used to support irradiations in US Material Test Reactors (MTRs). Previous research conducted through NEET ASI1-3 has shown that the MPFD technology could be made robust and was successfully tested in a reactor core. This new project will further the MPFD technology for higher temperature regimes and other reactor applications by developing a HT MPFD suitable for temperatures up to 800 °C. This report summarizes the research progress for year one of this three year project. Highlights from research accomplishments include: A joint collaboration was initiated between INL, KSU, and CEA. Note that CEA is participating at their own expense because of interest in this unique new sensor. An updated HT MPFD design was developed. New high temperature-compatible materials for HT MPFD construction were procured. Construction methods to support the new design were evaluated at INL. Laboratory evaluations of HT MPFD were initiated. Electrical contact and fissile material plating has been performed at KSU. Updated detector electronics are undergoing evaluations at KSU. A

  12. A parameterization of nuclear track profiles in CR-39 detector

    Science.gov (United States)

    Azooz, A. A.; Al-Nia'emi, S. H.; Al-Jubbori, M. A.

    2012-11-01

    In this work, the empirical parameterization describing the alpha particles’ track depth in CR-39 detectors is extended to describe longitudinal track profiles against etching time for protons and alpha particles. MATLAB based software is developed for this purpose. The software calculates and plots the depth, diameter, range, residual range, saturation time, and etch rate versus etching time. The software predictions are compared with other experimental data and with results of calculations using the original software, TRACK_TEST, developed for alpha track calculations. The software related to this work is freely downloadable and performs calculations for protons in addition to alpha particles. Program summary Program title: CR39 Catalog identifier: AENA_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AENA_v1_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: Copyright (c) 2011, Aasim Azooz Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met • Redistributions of source code must retain the above copyright, this list of conditions and the following disclaimer. • Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution This software is provided by the copyright holders and contributors “as is” and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright owner or contributors be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and

  13. Fission track dating evidence on tectonic activities of northern Himalaya block

    International Nuclear Information System (INIS)

    Yuan Wanming; Wang Shicheng; Wang Lanfen

    2002-01-01

    Fission track ages (FTA) of 4 apatite samples collected from Langkazi to Yarlung Zangbo thrust zone range between 13.6 and 17.2 Ma, reflecting the time of continent-continent collision and differing from previous data. The negative correlation between the FTA and sample elevations shows there was rapid uplifting during the continent-continent collision with uplifting rate of 176 m/Ma. Denudation degree, denudation rate and cooling rate were ∼2.9 km, 213 m/Ma and 7 degree C/Ma respectively since 13.6 Ma. FTA of 3 zircon samples are different significantly and have x 2 test value of < 0.1%, confirming the orogeny within continent went under low temperature

  14. Improving process methodology for measuring plutonium burden in human urine using fission track analysis

    International Nuclear Information System (INIS)

    Krahenbuhl, M.P.; Slaughter, D.M.

    1998-01-01

    The aim of this paper is to clearly define the chemical and nuclear principles governing Fission Track Analysis (FTA) to determine environmental levels of 239 Pu in urine. The paper also addresses deficiencies in FTA methodology and introduces improvements to make FTA a more reliable research tool. Our refined methodology, described herein, includes a chemically-induced precipitation phase, followed by anion exchange chromatography and employs a chemical tracer, 236 Pu. We have been able to establish an inverse correlation between Pu recovery and sample volume and our data confirms that increases in sample volume do not result in higher accuracy or lower detection limits. We conclude that in subsequent studies, samples should be limited to approximately two liters. The Pu detection limit for a sample of this volume is 2.8 μBq/l. (author)

  15. Fission-track dating of pumice from the KBS Tuff, East Rudolf, Kenya

    Science.gov (United States)

    Hurford, A.J.; Gleadow, A.J.W.; Naeser, C.W.

    1976-01-01

    Fission-track dating of zircon separated from two pumice samples from the KBS Tuff in the Koobi Fora Formation, in Area 131, East Rudolf, Kenya, gives an age of 2.44??0.08 Myr for the eruption of the pumice. This result is compatible with the previously published K-Ar and 40Ar/ 39Ar age spectrum estimate of 2.61??0.26 Myr for the KBS Tuff in Area 105, but differs from the more recently published K-Ar date of 1.82??0.04 Myr for the KBS Tuff in Area 131. This study does not support the suggestion that pumice cobbles of different ages occur in the KBS Tuff. ?? 1976 Nature Publishing Group.

  16. Fission track dating of mesozoic sandstones and its tectonic significance in the Eastern Sichuan Basin, China

    International Nuclear Information System (INIS)

    Shen Chuanbo; Mei Lianfu; Xu Sihuang

    2009-01-01

    To establish the tectonic evolution of the eastern Sichuan basin, apatite fission track dating and time-temperature thermal history modeling were carried to analyze on 11 samples collected from Jurassic sandstones. The results indicate that the cooling and exhumation process of the eastern Sichuan basin can be divided into three stages since Cretaceous, (1) a rapid cooling phase between ∼100 and ∼70 Ma, (2) following by a period of relative thermal stability phase between ∼70 and ∼15 Ma, (3) and then a new rapid cooling stage after ∼15 Ma. Two rapid cooling events imply that the eastern Sichuan basin once underwent two tectonic movements since Cretaceous. The first rapid cooling is associated with Mesozoic tectonic reactivation beginning at 100 Ma, which result in folds and faults of the eastern Sichuan basin. The second tectonic movement occurred at 15 Ma, which is related to denudation by compression resulting from the eastward growth of Tibetan plateau uplift.

  17. Application of fission track method in the development study of coalbed methane

    International Nuclear Information System (INIS)

    Li Xiaoming; Peng Gelin

    2002-01-01

    In order to explore potential resource of coalbed methane in Xinji coal deposit of Huainan coalfield, its tectonic-thermal evolution history was studied by using fission track technique. The results showed that there had been 3 or more times of significant thermal events occurred in this area since the late Paleozoic Era. The paleo-geothermal gradient was higher than that of the present. It was estimated that the denudation thickness in this area should be over 2000 m. Mainly formed between 240-140 Ma, no abundant methane could be generated in such condition. Furthermore, the tectonic-thermal events would release the most of methane gases. So, the potential resource of the coalbed methane in this are might be limited

  18. An international research project on Armenian archaeological sites: fission-track dating of obsidians

    Energy Technology Data Exchange (ETDEWEB)

    Badalian, R.; Bigazzi, G. E-mail: g.bigazzi@iggi.pi.cnr.it; Cauvin, M.-C.; Chataigner, C.; Jrbashyan, R.; Karapetyan, S.G.; Oddone, M.; Poidevin, J.-L

    2001-06-01

    In the Mediterranean and adjacent regions, the Caucasus is one of the less studied areas in relation to provenance studies of prehistoric obsidian artefacts. In the frame of an international INTAS research project, an extensive surveying and sampling campaign was carried out in the numerous obsidian bearing volcanic complexes of Armenia. 33 obsidian samples were analysed using the fission-track dating method in order to characterise the potential sources of the numerous artefacts found in prehistoric sites. Ages cluster into five groups--Upper Neopleistocene Q{sub III}, Middle Neopleistocene Q{sub II}, Lower Neopleistocene Q{sub I}, Lower Eopleistocene Q{sub EI} and Lower Pliocene N{sub 3}{sup 1} groups. This research represents a significant contribution to a better knowledge of chronology of Armenian volcanism for which only few data were available. The resulting data-set appears to be a solid base for future provenance studies.

  19. On the use of thin natural uranium film dosimetry in mineral dating by the fission track method

    International Nuclear Information System (INIS)

    Hadler Neto, J.C.; Iunes, P.J.; Khouri, M.C.

    1993-01-01

    Three obsidian samples were irradiated in a neutron facility and their age was measured by the fission track method; using a thin uranium film dosemeter. The results were compared to others made previously on the same type of rock using conventional neutron dosimetry. The use of thin uranium film for age determination is discussed. (F.E.). 20 refs, 4 tabs

  20. Application of fission track and other new technics in the study of geothermal history for Liaohe Basin

    International Nuclear Information System (INIS)

    Xia Yuliang; Zhu Jiechen; Zheng Maogong; Zhao Yunlong; Hu Zhenduo; Guo Xiuying; Gao Shangkui

    1994-11-01

    Mainly based on the study of fission track of the apatites, as well as geochronology, stable isotope composition and inclusion analysis, the principle and method of studying the geothermal history of sedimentary basin have been expounded systematically, and the source of sediment materials, and the geothermal characteristics of five section areas in Liaohe Basin were determined. The results of apatites and zircons U-Pb dating indicate that the materials of Shahejie Group in Liaohe Basin derived from the Shanhaiguan old land, and the record time of fission track of the apatites started at 172 Ma ago. On the basis of the studies of fission track characters of 100 apatite samples, stable isotopes and inclusion analysis, the annealing zone of fission track, oil generation zone and the old geothermal gradient were determined respectively in the western slope, southern part of western depression, Niuju area, Huangjindai area of eastern depression and Shallow sea area. It has provided the important scientific basis of reevaluating oil resources in Liaohe Basin. (2 tabs.)

  1. On the fission track dating and annealing behaviour of accessory minerals of Eastern Ghats (Andhra Pradesh, India)

    International Nuclear Information System (INIS)

    Koul, S.L.

    1978-01-01

    Use of the etching of fission fragment damage tracks for an estimation of the uranium content of apatite and zircon crystals is described. The etching conditions have been studied for which visible tracks are developed. Fission track determined ages of 25 samples of apatite and zircon crystals from four widely separated regions of India; the Borra mines (Vishakapatanam), Kashipatnam (Vishakapatnam), the Khamam area (Andhra Pradesh) and the Kodrama mines (Bihar) have been determined. Mean ages for these regions are 456 +- 5, 389 +- 4, 486 +- 7 and 664 +- 7 million years respectively. It is concluded that the fission track ages of the minerals date the last metamorphic event of the Eastern Ghats, known as the Indian Ocean Cycle. Annealing studies confirm that radiation damaged fossil tracks can be erased in minerals under intense metamorphic episodes, thus resetting the geological clock. Extrapolation of the experimentally determined temperatures for annealing suggest that a temperature of 170 0 C in 10 6 years will erase all the tracks in the apatite mineral. The uranium concentration has been estimated to be approximately 10 -8 gm/gm in apatite and approximately 10 -6 gm/gm in zircon. (Auth.)

  2. Fission track dating of volcanic glass: experimental evidence for the validity of the Size-Correction Method

    International Nuclear Information System (INIS)

    Bernardes, C.; Hadler Neto, J.C.; Lattes, C.M.G.; Araya, A.M.O.; Bigazzi, G.; Cesar, M.F.

    1986-01-01

    Two techniques may be employed for correcting thermally lowered fission track ages on glass material: the so called 'size-correcting method' and 'Plateau method'. Several results from fission track dating on obsidian were analysed in order to compare the model rising size-correction method with experimental evidences. The results from this work can be summarized as follows: 1) The assumption that mean size of spontaneous and induced etched tracks are equal on samples unaffected by partial fading is supported by experimental results. If reactor effects such as an enhancing of the etching rate in the irradiated fraction due to the radiation damage and/or to the fact that induced fission releases a quantity of energy slightly greater than spontaneous one exist, their influence on size-correction method is very small. 2) The above two correction techniques produce concordant results. 3) Several samples from the same obsidian, affected by 'instantaneous' as well as 'continuous' natural fading to different degrees were analysed: the curve showing decreasing of spontaneous track mean-size vs. fraction of spontaneous tracks lost by fading is in close agreement with the correction curve constructed for the same obsidian by imparting artificial thermal treatements on induced tracks. By the above points one can conclude that the assumptions on which size-correction method is based are well supported, at least in first approximation. (Author) [pt

  3. Development of a cylindrical tracking detector with multichannel scintillation fibers and pixelated photon detector readout

    Energy Technology Data Exchange (ETDEWEB)

    Akazawa, Y.; Miwa, K.; Honda, R.; Shiozaki, T.; Chiga, N.

    2015-07-01

    We are developing a cylindrical tracking detector for a Σp scattering experiment in J-PARC with scintillation fibers and the Pixelated Photon Detector (PPD) readout, which is called as cylindrical fiber tracker (CFT), in order to reconstruct trajectories of charged particles emitted inside CFT. CFT works not only as a tracking detector but also a particle identification detector from energy deposits. A prototype CFT consisting of two straight layers and one spiral layer was constructed. About 1100 scintillation fibers with a diameter of 0.75 mm (Kuraray SCSF-78 M) were used. Each fiber signal was read by Multi-Pixel Photon Counter (MPPC, HPK S10362-11-050P, 1×1 mm{sup 2}, 400 pixels) fiber by fiber. MPPCs were handled with Extended Analogue Silicon Photomultipliers Integrated ReadOut Chip (EASIROC) boards, which were developed for the readout of a large number of MPPCs. The energy resolution of one layer was 28% for a 70 MeV proton where the energy deposit in fibers was 0.7 MeV.

  4. CR-39 α track detector and its application in observing of the hot particles in environment

    International Nuclear Information System (INIS)

    Zou Benchuan

    1992-01-01

    CR-39 α track detector is a new α remitting radionuclides plastic detector. It is audio-visual, convenient and economic in the detection of α particle track and the distribution of α emitting radionuclides in environmental samples. CR-39 α track detector is used to observe the hot particles in rock and the hot particles coming from the liquid effluents discharged by spent fuel reprocessing plant in UK in marine environment and got good results

  5. Thermal stability of dyed tracks and electrochemical etching sensitivity of some polymeric detectors

    International Nuclear Information System (INIS)

    Monnin, M.; Gourcy, J.; Somogyi, G.; Dajko, D.

    1980-01-01

    Recent results on the mechanism of the formation of tracks obtained by the dyed tracks technique are given and the thermal annealing of the detectors is used to demonstrate their ability to retain tracks under more severe conditions than by the etching technique. Electrochemical etching of polycarbonate and polyethylene terephthalate detectors is investigated both from the background and sensitivity points of view. The polyethylene terephthalate detector is shown to be well suited for low neutron flux measurements. (author)

  6. Etching Properties of Poly ethyleneterephthalate (PET) Melinex-E Nuclear Track Detectors (NTDs)

    International Nuclear Information System (INIS)

    Ghanim, E.H.; Hussein, A.; El-samman, H.M.; Tretyakova, S.P.

    2009-01-01

    One of the main parameters that control track formation is the bulk etch rate, VB. The dependence of VB on etchant concentrations and temperatures was extensively carried out. It is found that, VB of the PET Melinex-E (C 10 H 8 O 4 ) depends upon the etchant temperature T through an Arrhenius equation. While, the dependence of VB on the etchant concentration; C followed the relation VB = A C n. The activation energy of etching, Eb, for the studied Melinex-E detector was calculated. An average value of Eb = 0.83 ± 0.03 eV was extracted. The variation of, VB, of PET with etching duration was studied and compared with that of CR-39 plastic at certain etching temperature; T e =60 degree C and at different etchant concentrations. The irradiation facilities were performed with the 252 Cf fission fragments and 129 Xe +8 (θi =π/2). Results of these studies were discussed in the frame work of nuclear track formation and etching theories

  7. Fast Neutron Dosimetry Using CR-39 Nuclear Track Detector

    International Nuclear Information System (INIS)

    ZAKI, M.; ABDEL-NABY, A.; MORSY, A.

    2010-01-01

    Measurement of the neutron dose in and around the neutron sources is important for the purpose of personnel and environmental neutron dosimetry. In the present study, a method for the measurement of neutron dose using the UV-Vis spectra of CR-39 plastic track detector was investigated. A set of CR-39 plastic detectors was exposed to 252 Cf neutron source, which had the yield of 0.68x10 8 /s, and neutron dose equivalent rate 1m apart from the source is equal to 3.8 mrem/h. The samples were etched for 10 h in 6.25 N NaOH at 70 o C. The absorbance of the etched samples was measured using UV-visible spectrophotometer as a function of neutron dose. It was observed that there was a linear relationship between the optical absorption of these detectors and neutron dose. This means that the exposure dose of neutron can be determined by knowing the optical absorption of the sample. These results were compared with previous study. It was found that there was a matching and good agreement with their investigations.

  8. The Control System for the CMS Strip Tracking Detector

    CERN Document Server

    Fahrer, Manuel; Chen, Jie; Dierlamm, Alexander; Frey, Martin; Masetti, Lorenzo; Militaru, Otilia; Shah, Yousaf; Stringer, Robert; Tsirou, Andromachi

    2008-01-01

    The Tracker of the CMS silicon strip tracking detector covers a surface of 206 m2. 9648128 channels are available on 75376 APV front-end chips on 15232 modules, built of 24328 silicon sensors. The power supply of the detector modules is split up in 1944 power supplies with two low voltage for front end power and two high voltage channels each for the bias voltage of the silicon sensors. In addition 356 low voltage channels are needed to power the control chain. The tracker will run at -20°C at low relative humidity for at least 10 years. The Tracker Control System handles all interdependencies of control, low and high voltages, as well as fast ramp downs in case of higher than allowed temperatures or currents in the detector and experimental cavern problems. This is ensured by evaluating $10^{4}$ power supply parameters, $10^{3}$ information from Tracker Safety System and $10^{5}$ information from the tracker front end.

  9. Apatite fission track analysis: geological thermal history analysis based on a three-dimensional random process of linear radiation damage

    International Nuclear Information System (INIS)

    Galbraith, R.F.; Laslett, G.M.; Green, P.F.; Duddy, I.R.

    1990-01-01

    Spontaneous fission of uranium atoms over geological time creates a random process of linearly shaped features (fission tracks) inside an apatite crystal. The theoretical distributions associated with this process are governed by the elapsed time and temperature history, but other factors are also reflected in empirical measurements as consequences of sampling by plane section and chemical etching. These include geometrical biases leading to over-representation of long tracks, the shape and orientation of host features when sampling totally confined tracks, and 'gaps' in heavily annealed tracks. We study the estimation of geological parameters in the presence of these factors using measurements on both confined tracks and projected semi-tracks. Of particular interest is a history of sedimentation, uplift and erosion giving rise to a two-component mixture of tracks in which the parameters reflect the current temperature, the maximum temperature and the timing of uplift. A full likelihood analysis based on all measured densities, lengths and orientations is feasible, but because some geometrical biases and measurement limitations are only partly understood it seems preferable to use conditional likelihoods given numbers and orientations of confined tracks. (author)

  10. The ZEUS central tracking detector. Der zentrale Spuren-Detektor von ZEUS

    Energy Technology Data Exchange (ETDEWEB)

    Saxon, D H

    1989-12-01

    The Central Tracking Detector (CTD) of ZEUS covers a wide angular range, whilst the Forward Detector - comprising the Forward Tracking Detector (FTD) and electron identification by transition radiation - concentrates on the important forward cone. The RTD (Rear Tracking Detector) provides accurate angle measurement of the recoil electron and the vertex detector (VXD) aims to find particles from heavy flavour decay. To measure momentum accurately the CTD sits in a high magnetic field (B=1,8 T) within the ZEUS calorimeter. (orig./HSI).

  11. Trace uranium analysis in Indian coal samples using the fission track technique

    International Nuclear Information System (INIS)

    Jojo, P.J.; Rawat, A.; Kumar, Ashavani; Prasad, Rajendra

    1993-01-01

    The ever-growing demand for energy has resulted in the extensive use of fossil fuels, especially coal, for power generation. Coal and its by-products often contain significant amounts of radionuclides, including uranium, which is the ultimate source of the radioactive gas Radon-222. The present study gives the concentration of uranium in coal samples of different collieries in India, collected from various thermal power plants in the state of Uttar Pradesh. The estimates were made using the fission track technique. Latent damage tracks were not found to be uniformly distributed but showed sun bursts and clusters. Non-uniform distributions of trace elements are a very common phenomenon in rocks. The levels of uranium in the coal samples were found to vary from 2.0 to 4.9 ppm in uniform distributions and from 21.3 to 41.0 ppm in non-uniform distributions. Measurements were also made on fly ash samples where the average uranium concentration was found to be 8.4 and 49.3 ppm in uniform and non-uniform distributions, respectively. (author)

  12. NEET Enhanced Micro-Pocket Fission Detector for High Temperature Reactors - FY16 Status Report

    Energy Technology Data Exchange (ETDEWEB)

    Unruh, Troy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Reichenberger, Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Stevenson, Sarah [Idaho National Lab. (INL), Idaho Falls, ID (United States); Tsai, Kevin [Idaho National Lab. (INL), Idaho Falls, ID (United States); McGregor, Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    A collaboration between the Idaho National Laboratory (INL), the Kansas State University (KSU), and the French Atomic Energy Agency, Commissariat à l'Énergie Atomique et aux Energies Alternatives, (CEA), has been initiated by the Nuclear Energy Enabling Technologies (NEET) Advanced Sensors and Instrumentation (ASI) program for developing and testing High Temperature Micro-Pocket Fission Detectors (HT MPFD), which are compact fission chambers capable of simultaneously measuring thermal neutron flux, fast neutron flux and temperature within a single package for temperatures up to 800 °C. The MPFD technology utilizes a small, multi-purpose, robust, in-core fission chambers and thermocouple. As discussed within this report, the small size, variable sensitivity, and increased accuracy of the MPFD technology represent a revolutionary improvement over current methods used to support irradiations in US Material Test Reactors (MTRs). Previous research conducted through NEET ASI1-3 has shown that the MPFD technology could be made robust and was successfully tested in a reactor core. This new project will further the MPFD technology for higher temperature regimes and other reactor applications by developing a HT MPFD suitable for temperatures up to 800 °C. This report summarizes the research progress for year two of this three year project. Highlights from research accomplishments include: • Continuation of a joint collaboration between INL, KSU, and CEA. Note that CEA is participating at their own expense because of interest in this unique new sensor. • An updated parallel wire HT MPFD design was developed. • Program support for HT MPFD deployments was given to Accident Tolerant Fuels (ATF) and Advanced Gas-cooled Reactor (AGR) irradiation test programs. • Quality approved materials for HT MPFD construction were procured by irradiation test programs for upcoming deployments. • KSU improved and performed electrical contact and fissile material plating.

  13. Apatite fission track dating of the Northern Western Shield, Western Australia

    International Nuclear Information System (INIS)

    Weber, U.D.; Kohn, B.P.; Gleadow, A.J.W.

    1999-01-01

    Full text:The investigation of the thermotectonic evolution of the northern part of the Precambrian Western Shield of Western Australia using apatite fission track (AFT) thermochronology is the main focus of this study. The study area encompasses Precambrian rocks of the Pilbara Craton and the northern part of the Yilgarn Craton including the Narryer Gneiss Complex. AFT data, mostly from the Archaean cratons reveal cooling ages ranging between 260±8 Ma and 400±20 Ma. Mean confined horizontal track lengths fall between ∼12 and 13 μm with standard deviations ranging from 1.1-2.2 μm. Forward modelling of time-temperature history paths for representative samples reveals a period of regional cooling of at least ∼50 deg C in the late Palaeozoic. Most paths also show a second period of cooling of 25 deg C from temperatures of ∼80-85 deg C. This later cooling episode occurred in the Mesozoic but its timing is less well constrained. Assuming that the average present day geothermal gradient of ∼18±2 deg C per km - 1 was prevalent since the late Palaeozoic, then the minimum of ∼75 deg C of cooling predicted by the fission track modelling suggests overall denudation of at least ∼ 3.7-4.6 km of section since that time. Phanerozoic basins (Perth, Carnarvon and Canning) adjacent to the north and west of the northern Western Shield mostly continue offshore and form complex structures containing up to ∼ 15 km of predominantly clastic sediments of early Ordovician to late Cretaceous age. The basins are likely to have been depocentres for much of the detritus derived from the denudation inferred from the cooling recorded by the AFT. Possible causative events which could be linked to the observed late Palaeozoic cooling are tectonism related to the collision of Gondwanaland with Laurussia in Carboniferous time forming the supercontinent Pangea or a possible far-field effect related to the Alice Springs Orogeny. Further low temperature thermochronological studies

  14. Convection methodology for fission track annealing: direct and inverse numerical simulations in the multi-exponential case

    International Nuclear Information System (INIS)

    Miellou, J.C.; Igli, H.; Grivet, M.; Rebetez, M.; Chambaudet, A.

    1994-01-01

    In minerals, the uranium fission tracks are sensitive to temperature and time. The consequence is that the etchable lengths are reduced. To simulate the phenomenon, at the last International Conference on Nuclear Tracks in solids at Beijing in 1992, we proposed a convection model for fission track annealing based on a reaction situation associated with only one activation energy. Moreover a simple inverse method based on the resolution of an ordinary differential equation was described, making it possible to retrace the thermal history in this mono-exponential situation. The aim of this paper is to consider a more involved class of models including multi-exponentials associated with several activation energies. We shall describe in this framework the modelling of the direct phenomenon and the resolution of the inverse problem. Results of numerical simulations and comparison with the mono-exponential case will be presented. 5 refs. (author)

  15. Understanding the uplift pattern in Mesozoic and Cenozoic,, eastern Dabie area, China using fission track dating of apatite

    International Nuclear Information System (INIS)

    Wu Qianhong; Liu Shunsheng

    2002-01-01

    By using the fission track dating technique, a preliminary study was carried out on the fission track ages (FTA) of apatite, their distribution patterns and hints over the tectonics activities during Mesozoic and Cenozoic in the east Dabie area. Attempts were also made to improve the conventional statistical method for the tracks. Ranging from 59.4 +- 3.4 Ma to 105.6 +- 9.8 Ma, the FTA results of apatite spread in the wide range and increased rapidly from the east to the west area. Sine 95 Ma, the uplift rate has been quite slow and asymmetry. The FTA value in the middle area of Xiaotian-Mozitan Fault may imply its uplift in Cretaceous. The faulting should be the main control factor for the uplift of this area

  16. Two specialized delayed-neutron detector designs for assays of fissionable elements in water and sediment samples

    International Nuclear Information System (INIS)

    Balestrini, S.J.; Balagna, J.P.; Menlove, H.O.

    1976-01-01

    Two specialized neutron-sensitive detectors are described which are employed for rapid assays of fissionable elements by sensing for delayed neutrons emitted by samples after they have been irradiated in a nuclear reactor. The more sensitive of the two detectors, designed to assay for uranium in water samples, is 40% efficient; the other, designed for sediment sample assays, is 27% efficient. These detectors are also designed to operate under water as an inexpensive shielding against neutron leakage from the reactor and neutrons from cosmic rays. (Auth.)

  17. A new fission-fragment detector to complement the CACTUS-SiRi setup at the Oslo Cyclotron Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Tornyi, T.G., E-mail: tornyitom@atomki.hu [Department of Physics, University of Oslo (Norway); Institute of Nuclear Research of the Hungarian Academy of Sciences (MTA Atomki), Debrecen (Hungary); Görgen, A.; Guttormsen, M.; Larsen, A.C.; Siem, S. [Department of Physics, University of Oslo (Norway); Krasznahorkay, A. [Institute of Nuclear Research of the Hungarian Academy of Sciences (MTA Atomki), Debrecen (Hungary); Csige, L. [Institute of Nuclear Research of the Hungarian Academy of Sciences (MTA Atomki), Debrecen (Hungary); Max-Planck-Institute for Quantum Optics, D-85748 Garching (Germany)

    2014-02-21

    An array of Parallel Plate Avalanche Counters (PPAC) for the detection of heavy ions has been developed. The new device, NIFF (Nuclear Instrument for Fission Fragments), consists of four individual detectors and covers 60% of 2π. It was designed to be used in conjunction with the SiRi array of ΔE−E silicon telescopes for light charged particles and fits into the CACTUS array of 28 large-volume NaI scintillation detectors at the Oslo Cyclotron Laboratory. The low-pressure gas-filled PPACs are sensitive for the detection of fission fragments, but are insensitive to scattered beam particles of light ions or light-ion ejectiles. The PPAC detectors of NIFF have good time resolution and can be used either to select or to veto fission events in in-beam experiments with light-ion beams and actinide targets. The powerful combination of SiRi, CACTUS, and NIFF provides new research opportunities for the study of nuclear structure and nuclear reactions in the actinide region. The new setup is particularly well suited to study the competition of fission and γ decay as a function of excitation energy.

  18. Radon measurements by track detectors in Calabrian workplaces

    Energy Technology Data Exchange (ETDEWEB)

    Nastro, V.; Niceforo, G.; Vuono, D.; Luca, P. de; Nastro, A. [Calabria Univ., Dipt. di Pianificazione Territoriale, Arcavacata di Rende, CS (Italy)

    2006-07-01

    Indoor radon studies have been carried out in some workplaces of the South Calabria (Italy) by track detectors CR-39. This study has been undertaken for the purpose of safeguarding the public healthy: since the European population spends, in average, the most greater part of their time in confined environments(residences and offices) the risks of exposure can be elevated. This radon passive measurements are been effectuated according to the recommendations. The exposure time in the workplaces was two different cycle: three months, and six months. The obtained results indicate a radon concentration not only in an average of low level but also in the range of action level (>500 Bq/m{sup 3}). In this last case will be necessary to reduce the radon pollution by adequate land operation works, and a continuous monitoring is also necessary.

  19. Radon measurements by track detectors in Calabrian workplaces

    International Nuclear Information System (INIS)

    Nastro, V.; Niceforo, G.; Vuono, D.; Luca, P. de; Nastro, A.

    2006-01-01

    Indoor radon studies have been carried out in some workplaces of the South Calabria (Italy) by track detectors CR-39. This study has been undertaken for the purpose of safeguarding the public healthy: since the European population spends, in average, the most greater part of their time in confined environments(residences and offices) the risks of exposure can be elevated. This radon passive measurements are been effectuated according to the recommendations. The exposure time in the workplaces was two different cycle: three months, and six months. The obtained results indicate a radon concentration not only in an average of low level but also in the range of action level (>500 Bq/m 3 ). In this last case will be necessary to reduce the radon pollution by adequate land operation works, and a continuous monitoring is also necessary

  20. Precision Muon Tracking Detectors for High-Energy Hadron Colliders

    CERN Document Server

    Gadow, Philipp; Kroha, Hubert; Richter, Robert

    2016-01-01

    Small-diameter muon drift tube (sMDT) chambers with 15 mm tube diameter are a cost-effective technology for high-precision muon tracking over large areas at high background rates as expected at future high-energy hadron colliders including HL-LHC. The chamber design and construction procedures have been optimized for mass production and provide sense wire positioning accuracy of better than 10 ?m. The rate capability of the sMDT chambers has been extensively tested at the CERN Gamma Irradiation Facility. It exceeds the one of the ATLAS muon drift tube (MDT) chambers, which are operated at unprecedentedly high background rates of neutrons and gamma-rays, by an order of magnitude, which is sufficient for almost the whole muon detector acceptance at FCC-hh at maximum luminosity. sMDT operational and construction experience exists from ATLAS muon spectrometer upgrades which are in progress or under preparation for LHC Phase 1 and 2.

  1. A passive monitor for radon using electrochemical track etch detector

    International Nuclear Information System (INIS)

    Massera, G.E.; Hassib, G.M.; Piesch, E.

    1980-01-01

    A passive monitor for radon and its decay products based on the electrochemical etching (ECE) of α-particle tracks on Makrofol is described. The monitor has been constructed in such a way that radon and radon daughters attached to aerosols can easily pass through a chamber while dust, heavy particles and water droplets are collected outside. The decay products are accumulated on the bottom of the chamber and a Makrofol detector foil is fixed on the top to register alpha particles. The ECE condition was maintained to detect alpha particles coming mainly from radon daughters trapped on the bottom of the chamber. The response of the monitor was determined at different exposure conditions and compared with those of some active techniques such as working level meters. The merits of this system are low cost, good sensitivity, portability and reliable, unattended operation. (author)

  2. Radon measurements using track detector in Wadi Sannur cave

    International Nuclear Information System (INIS)

    Shahin, F.; Eissa, M.F.; Mostafa, R.M.

    2008-01-01

    The most important contributors to the committed effective dose received by population due to natural sources are the short-lived decay products of radon ( 222 Rn). In natural voids, such as caves, most radon will enter the system from diffusion across the rock-air interface. It is well known that factors such as air pressure and temperature control the distribution of radon. The radon concentration measurements in the Wadi Sannur cave in Beni-Suef governorate in the period from 14 th of July 2005 to 17 th of October 2005. The average radon concentrations in the right, left and whole first cave are 916.12 ± 179.09, 819.63 ± 54.72 and 873.90± 147.11 Bq m -3 respectively. The measurements were performed using track etch detector of type Cr-39. After exposure, all detectors were etched chemically in 6.25 M NaOH solution at 70 C degrees for 6 h. The tracks were counted with an optical microscope magnifying 400 times. The average temperature inside the first cave during the period of measurements is 25-26 C degrees. The annual effective doses for the workers and visitors in the cave have been calculated. The average radon concentration in the Wadi Sannur cave, was 873.90 ± 147.11 Bq m -3 . The annual effective doses for worker and visitor in the cave were 1.33 ± 0.24 and 0.041 ± 0.007 mSv respectively. The doses are within the international recommended dose of 1.15 mSv. (author)

  3. Fission cross section measurements for minor actinides

    Energy Technology Data Exchange (ETDEWEB)

    Fursov, B. [IPPE, Obninsk (Russian Federation)

    1997-03-01

    The main task of this work is the measurement of fast neutron induced fission cross section for minor actinides of {sup 238}Pu, {sup 242m}Am, {sup 243,244,245,246,247,248}Cm. The task of the work is to increase the accuracy of data in MeV energy region. Basic experimental method, fissile samples, fission detectors and electronics, track detectors, alpha counting, neutron generation, fission rate measurement, corrections to the data and error analysis are presented in this paper. (author)

  4. Use of combined alpha-spectrometry and fission track analysis for the determination of 240Pu/239Pu ratios in human tissue

    International Nuclear Information System (INIS)

    Love, S.F.; Filby, R.H.; Glover, S.E.; Stuit, D.B.; Kathren, R.L.

    1998-01-01

    Plutonium and other actinides were determined in human autopsy tissues of occupationally exposed workers who were registrants of the United States Transuranium and Uranium Registries (USTUR). In this study, Pu was purified and isolated from Am, U and Th, after drying and wet-ashing of the tissues, and the addition of 238 Pu as a radiotracer. After electrodeposition onto vanadium planchets, the 239+240 Pu activity was determined by alpha-spectrometry. A fission track method was developed to determine 239 Pu in the presence of 238 Pu and 240 Pu, using Lexan TM polycarbonate detectors. Combining the two techniques allowed the determination of the 240 Pu/ 239 Pu activity and atom ratios. Data from selected USTUR cases are presented. (author)

  5. Equipment for electrochemical etching of dielectric track detectors

    International Nuclear Information System (INIS)

    Turek, K.; Novak, M.

    1992-01-01

    The facility is designed for electrochemical etching of solid state track detectors, devised for thicknesses in excess of 200 μm as employed for direct detection of charged particles or neutrons. The device consists of a high-voltage a.c. supply for the electrodes and an assembly whose body consists of a flat tank, on the surface of which is formed a channel for feeding the heating and cooling media. The tank is covered by a gasket, an earthed metal plate for the detector, a mask with holes determining the shape of the etched area, and a pressure plate. The pressure plate is fitted with a system of holes for the etching solution. Needle-shaped high-voltage electrodes are accommodated in the holes of the mask. The underlying principle of the invention consists in the fact that a rubber pad with guide holes for the needle-shaped electrodes lies on the pressure plate. Each electrode is composed of a central tip and an outer jacket, separated by an insulating layer; connection is provided by a light emitting diode. (Z.S.). 2 figs

  6. Cosmic radiation dose in aircraft - a neutron track etch detector

    Energy Technology Data Exchange (ETDEWEB)

    Vukovic, B.; Radolic, V.; Miklavcic, I.; Poje, M.; Varga, M. [Department of Physics, University of Osijek, 31000 Osijek, P.O. Box 125, Gajev trg 6 (Croatia); Planinic, J. [Department of Physics, University of Osijek, 31000 Osijek, P.O. Box 125, Gajev trg 6 (Croatia)], E-mail: planinic@ffos.hr

    2007-12-15

    Cosmic radiation bombards us at high altitude by ionizing particles. The radiation environment is a complex mixture of charged particles of solar and galactic origin, as well as of secondary particles produced in interaction of the galactic cosmic particles with the nuclei of atmosphere of the Earth. The radiation field at aircraft altitude consists of different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. The non-neutron component of cosmic radiation dose aboard ATR 42 and A 320 aircrafts (flight level of 8 and 11 km, respectively) was measured with TLD-100 (LiF:Mg,Ti) detectors and the Mini 6100 semiconductor dosimeter. The estimated occupational effective dose for the aircraft crew (A 320) working 500 h per year was 1.64 mSv. Other experiments, or dose rate measurements with the neutron dosimeter, consisting of LR-115 track detector and boron foil BN-1 or 10B converter, were performed on five intercontinental flights. Comparison of the dose rates of the non-neutron component (low LET) and the neutron one (high LET) of the radiation field at the aircraft flight level showed that the neutron component carried about 50% of the total dose. The dose rate measurements on the flights from the Middle Europe to the South and Middle America, then to Korea and Japan, showed that the flights over or near the equator region carried less dose rate; this was in accordance with the known geomagnetic latitude effect.

  7. Cosmic radiation dose in aircraft - a neutron track etch detector

    International Nuclear Information System (INIS)

    Vukovic, B.; Radolic, V.; Miklavcic, I.; Poje, M.; Varga, M.; Planinic, J.

    2007-01-01

    Cosmic radiation bombards us at high altitude by ionizing particles. The radiation environment is a complex mixture of charged particles of solar and galactic origin, as well as of secondary particles produced in interaction of the galactic cosmic particles with the nuclei of atmosphere of the Earth. The radiation field at aircraft altitude consists of different types of particles, mainly photons, electrons, positrons and neutrons, with a large energy range. The non-neutron component of cosmic radiation dose aboard ATR 42 and A 320 aircrafts (flight level of 8 and 11 km, respectively) was measured with TLD-100 (LiF:Mg,Ti) detectors and the Mini 6100 semiconductor dosimeter. The estimated occupational effective dose for the aircraft crew (A 320) working 500 h per year was 1.64 mSv. Other experiments, or dose rate measurements with the neutron dosimeter, consisting of LR-115 track detector and boron foil BN-1 or 10B converter, were performed on five intercontinental flights. Comparison of the dose rates of the non-neutron component (low LET) and the neutron one (high LET) of the radiation field at the aircraft flight level showed that the neutron component carried about 50% of the total dose. The dose rate measurements on the flights from the Middle Europe to the South and Middle America, then to Korea and Japan, showed that the flights over or near the equator region carried less dose rate; this was in accordance with the known geomagnetic latitude effect

  8. Thorium-uranium fission radiography

    Science.gov (United States)

    Haines, E. L.; Weiss, J. R.; Burnett, D. S.; Woolum, D. S.

    1976-01-01

    Results are described for studies designed to develop routine methods for in-situ measurement of the abundance of Th and U on a microscale in heterogeneous samples, especially rocks, using the secondary high-energy neutron flux developed when the 650 MeV proton beam of an accelerator is stopped in a 42 x 42 cm diam Cu cylinder. Irradiations were performed at three different locations in a rabbit tube in the beam stop area, and thick metal foils of Bi, Th, and natural U as well as polished silicate glasses of known U and Th contents were used as targets and were placed in contact with mica which served as a fission track detector. In many cases both bare and Cd-covered detectors were exposed. The exposed mica samples were etched in 48% HF and the fission tracks counted by conventional transmitted light microscopy. Relative fission cross sections are examined, along with absolute Th track production rates, interaction tracks, and a comparison of measured and calculated fission rates. The practicality of fast neutron radiography revealed by experiments to data is discussed primarily for Th/U measurements, and mixtures of other fissionable nuclei are briefly considered.

  9. Fast tracking detector with fiber scintillators and a position sensitive photomultiplier

    International Nuclear Information System (INIS)

    Salomon, M.; Li, V.; Smith, G.; Wu, Y.S.

    1988-11-01

    We have studied the properties of a tracking detector composed of 32 fiber scintillators coupled to a multianode photomultiplier placed in a pion beam at TRIUMF. We measured the efficiency of the detector, as well as its tracking capabilities and double hit resolution

  10. A proposal to study a tracking/preshower detector for the LHC

    CERN Document Server

    Munday, D J; Anghinolfi, Francis; Bonino, R; Campbell, M; Fassò, A; Gildemeister, O; Heijne, Erik H M; Jarron, Pierre; Mapelli, Livio P; Pentney, J M; Poppleton, Alan; Stevenson, Graham Roger; Gössling, C; Pollmann, D; Sondermann, V; Tsesmelis, E; Clark, A G; Kienzle-Focacci, M N; Martin, M; Rosselet, L; Fretwurst, E; Lindström, G; Reich, V; Bardos, R A; Gorfine, G W; Taylor, G; Tovey, Stuart N; Stapnes, Steinar; Weidberg, A R; Lubrano, P; Pepé, M; Grayer, Geoffrey H; Sharp, P; Bakich, A M; Peak, L S; CERN. Geneva. Detector Research and Development Committee

    1990-01-01

    We describe a program of studies aimed at determining whether the track stub/preshower technique of electron identification can be used at the highest operating luminosities of the proposed LHC collider. The proposal covers detector and electronics developments required for the construction of a track-stub and preshower detector preceding the electromagnetic calorimeter of an LHC experiment.

  11. Measurement of Radon concentration in groundwater by technique of nuclear track detector

    International Nuclear Information System (INIS)

    Trinh Van Giap; Nguyen Manh Hung; Dang Duc Nhan

    2000-01-01

    A method for measuring radon concentration in groundwater using nuclear track detector LR-115 stripping is reported. The radon-monitoring device in groundwater is a small box with two pieces of nuclear track detector and all these materials is placed in a plastic bag made by polyethylene. It is very suitable to measure radon concentration in groundwater well in long term. Alpha tracks produced by radon and it daughter on nuclear track detector is counted automatically by spark counting method. The paper also presents some results of radon concentration in some groundwater well and mineral water sources. (author)

  12. Assessment of plutonium exposures in Rongelap and Utirik populations by fission track analysis of urine

    International Nuclear Information System (INIS)

    Sun, L.C.; Moorthy, A.R.; Kaplan, E.; Baum, J.W.; Meinhold, C.B.

    1994-01-01

    A nuclear device, code-named Bravo, detonated at Bikini Atoll at 6:45 a.m. on 1 March 1954, unexpectedly released a large amount of radioactivity. Over 40 years after this incident, the study of its impact on the radiological health and environmental safety of the residents of Rongelap and Utirik Atolls continues. In 1987, researchers at Brookhaven National Laboratory established a fission track analysis (FTA) method for low-level 239 Pu urinalysis. Two years later, a new shipboard protocol was developed for collecting 24-h radiologically clean urine samples. The purpose of this paper is to update information on the FTA method for measuring low-levels of plutonium, and to summarize results on the distribution of 239 Pu in the populations of Rongelap and Utirik between 1981--1991. Plutonium detection levels (99% confidence level) in these samples were 2--3 μBq, which is equivalent to 0.2--0.3 mSv effective dose equivalent (EDE) to age 70 for Marshallese. The latest 1991 FTA data indicate average EDE of 0.62 mSv and 1.6 mSv for the people of Rongelap and Utirik, respectively, which both are the highest values since 1988

  13. Fission track analysis method of urine plutonium and estimation of plutonium-239 internal dose to Marshallese

    International Nuclear Information System (INIS)

    Zhao Shixuan

    1995-01-01

    Bravo detonated at Bikini Atoll on the morning of March 1, 1954, unexpectedly released a large amount of radioactive fallout on the areas. Impact studies on the radiological health and safety of the residents living in the contaminated environments are still undergoing. For plutonium dose assessment, researchers at Brookhaven National Laboratory established a fission track analysis (FTA) method for low-level 239 Pu measurement. Furthermore, a new shipboard protocol was developed for collecting 24-h radiologically clean urine samples. The purposes of this paper are to update information on the FTA processes and to present a set of results on the 239 Pu measurements in the Marshallese populations (Rongelap and Utirik) between 1981-1991. The detection sensitivity of FTA method (99% confidence level) in these samples was 2-3 μBq which is equivalent to 0.2-0.3 mSv effective dose equivalent (EDE) to age 70 for the Marshallese. The latest 1991 FTA data indicate average EDE of 0.62 mSv and 1.6 mSv for the people of Rongelap and Utirik, respectively, which both are the highest values since 1988

  14. Cretaceous to present paleothermal gradients, central Negev, Israel: constraints from fission track dating

    International Nuclear Information System (INIS)

    Kohn, B.P.; Feinstein, S.; Eyal, M.

    1990-01-01

    Apatite and zircon fission track ages (FTA), vitrinite reflectance (VR) data and burial history curves were integrated for reconstruction of Early Cretaceous to present maximum thermal gradients in four deep boreholes in the central Negev, Isreal. The most complete data set is available from the Ramon 1 borehole. Supplementary data were obtained from Hameishar 1, Makhtesh Qatan 2, and Kurnub 1 boreholes. Between ca. 122-90 Ma the constraints on thermal gradient obtained from apatite FTA overlap with those derived from zircon FT and VR data, restricting them to 0 C km -l . Apatite FTA between 90 and 80 Ma in Ramon 1 and Hameishar 1 suggest rapid cooling at the time recorded or earlier. Constraints on thermal gradient history derived from these ages are considerably strengthened over a short time span. From 80 Ma to the present, FTA data indicate that gradients had probably decayed to present-day regional levels (ca. 20 0 C km -1 ) by Early Tertiary time. Thermal constraints derived from apatite FTA and VR data in Makhtesh Qatan 2 and Kurnub 1 boreholes are consistent with those obtained post-56 Ma for Ramon 1. For pre-56 Ma, only VR data are available and these indicate considerably lower maximum gradients than those obtained for the same time period from Ramon 1. This dichotomy reflects different Early Cretaceous-Early Tertiary thermal regimes between the northern and southern parts of the study area. (author)

  15. Assessment of plutonium exposures in Rongelap and Utirik populations by fission track analysis of urine

    International Nuclear Information System (INIS)

    Sun, L.C.; Moorthy, A.R.; Kaplan, E.; Baum, J.W.; Meinhold, C.B.

    1995-01-01

    A nuclear device, code-named Bravo, detonated at Bikini Atoll at 6.45 a.m. on 1 March 1954, unexpectedly released a large amount of radioactivity. Over 40 years after this incident, the study of its impact on the radiological health and environmental safety of the residents of Rongelap and Utirik Atolls continues. In 1987, researchers at Brookhaven National Laboratory established a fission track analysis (FTA) method for low-level 239 Pu urinalysis. Two years later, a new shipboard protocol was developed for collecting 24-h radiologically clean urine samples. The purpose of this paper is to update information on the FTA method for measuring low-levels of plutonium, and to summarize results on the distribution of 239 Pu in the populations of Rongelap and Utirik between 1981-1991. Plutonium detection levels (99% confidence level) in these samples were 2-3 μBq, which is equivalent to 0.2-0.3 mSv effective dose equivalent (EDE) to age 70 for Marshallese. The latest 1991 FTA data indicate average EDE of 0.62 mSv and 1.6 mSv for the people of Rongelap and Utirik, respectively, which both are the highest values since 1988. (author)

  16. Uranium content and fission track ages of some basalts from the FAMOUS area

    International Nuclear Information System (INIS)

    Storzer, Dieter; Selo, Madeleine

    1976-01-01

    The uranium contents of basalts from the rift valley in the Atlantic ocean near 37 deg N range between 75 ppb and 450 ppb. The fission track ages of these basalts range between 3x10 3 years and 6x10 5 years. They increase with distance from the axis of the median valley. Therefore, the locus of accretion of new crust seems to be restricted to a relatively narrow zone along the valley floor. In addition, the ages indicate that during the last 10 5 years the rate of accretion has been slower to the west than to the east. This indicates a migration of the active spreading center to the west by at least 1 km. the sea-floor spreading rates are high, up to 9cm/year, near the center of actual magmatic activity. They decrease with distance from the valley axis to 0.7 cm/year at about 2 km in the west respectively 1.5 cm/year at about 4 km in the east

  17. Distribution of uranium in dental porcelains by means of the fission track method

    International Nuclear Information System (INIS)

    Shimizu, Masami; Noguchi, Kunikazu; Moriwaki, Kazunari; Sairenji, Eiko

    1980-01-01

    Porcelain teeth, some of which contain uranium compounds for aesthetic purpose, have been widely used in dental clinics. Hazardous effects due to uranium radiation have been suggested by recent publications. In the previous study, the authors reported the uranium content of porcelain teeth and radiation dose by it. In this study, using the fission track method, the authors examined spatial distribution of uranium in dental porcelain teeth (4 brands) which were marketed in Japan. From each sample of porcelain tooth, a 1-mm-thick specimen was sliced, and uranium content was measured at every 0.19 mm from labial side to lingual side for making a uranium distribution chart. Higher uranium concentration was found in Trubyte Bioblend porcelain teeth (USA) and they showed almost uniform distribution of uranium, while those of the Japanese three brands indicated, in most case, comparatively lower concentration and found to be non-uniform distributions. Range of uranium concentration in these brands were N.D. -- 5.2 ppm (Shofu-Ace), N.D. -- 342 ppm (Shofu-Real), N.D. -- 47 ppm (G.C. Livdent) and N.D. -- 235 ppm (Trubyte Bioblend), respectively. (author)

  18. An extensive apatite fission-track study throughout the Northern Apennines Nappe belt

    International Nuclear Information System (INIS)

    Abbate, E.; Balestrieri, M.L.; Bigazzi, G.; Ventura, B.; Zattin, M.; Zuffa, G.G.

    1999-01-01

    This paper takes into consideration more than 100 apatite fission-track analyses on samples coming from an approximately west-east cross-section throughout the Northern Apennines. This collisional chain is made of structural units and nappes (Ligurian and Tuscan Nappe) accreted to the Adriatic Foreland during the Neogene, which overthrust the Miocene turbiditic successions of the Cervarola and Marnoso-arenacea Formations. Different cooling ages and degrees of annealing delineate different evolution histories for these units. Exhumation of the western outcrops of the Ligurian Nappe can be placed at 8 Ma and follows a first denudation event occurred in Eocene times. Timing of exhumation decreases eastwards. A break in this general trend is shown by the Apuan Alps, that occupy an intermediate position and yielded the youngest cooling ages. In the external part of the Marnoso-arenacea foredeep deposits this tendency could not be tested because total annealing of the apatite system has not been reached. In this case, modeling of data allows evaluating maximum burial temperatures

  19. Energy loss and online directional track visualization of fast electrons with the pixel detector Timepix

    Czech Academy of Sciences Publication Activity Database

    Granja, C.; Krist, Pavel; Chvátil, David; Šolc, J.; Pospíšil, S.; Jakubek, J.; Opalka, L.

    2013-01-01

    Roč. 59, DEC (2013), s. 245-261 ISSN 1350-4487 Institutional support: RVO:61389005 Keywords : interaction of radiation with matter * dE/dx detectors * particle tracking detectors * hybrid pixel detectors * active nuclear emulsion * energy loss Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.140, year: 2013

  20. Exhumation history of the NW Indian Himalaya revealed by fission track and 40Ar/39Ar ages

    Science.gov (United States)

    Schlup, Micha; Steck, Albrecht; Carter, Andrew; Cosca, Michael; Epard, Jean-Luc; Hunziker, Johannes

    2011-01-01

    New fission track and Ar/Ar geochronological data provide time constraints on the exhumation history of the Himalayan nappes in the Mandi (Beas valley) — Tso Morari transect of the NW Indian Himalaya. Results from this and previous studies suggest that the SW-directed North Himalayan nappes were emplaced by detachment from the underthrusted upper Indian crust by 55 Ma and metamorphosed by ca. 48–40 Ma. The nappe stack was subsequently exhumed to shallow upper crustal depths (

  1. Reconstructing Post-Carboniferous History of the Krkonoše Piedmont Basin Using Detrital Apatite Fission-Track Data

    Czech Academy of Sciences Publication Activity Database

    Martínek, K.; Svojtka, Martin; Filip, Jiří

    2006-01-01

    Roč. 20, - (2006), s. 91-92 ISSN 1210-9606. [Meeting of the Central European Tectonic Studies Group /4./. Zakopane, 19.04.2006-22.04.2006] Institutional research plan: CEZ:AV0Z30130516 Keywords : fission-track * Krkonoše * apatite Subject RIV: DB - Geology ; Mineralogy http://geolines.gli.cas.cz/fileadmin/volumes/volume20/G20-091b.pdf

  2. Ageing effects on polymeric track detectors: studies of etched tracks at nano size scale using atomic force microscope

    International Nuclear Information System (INIS)

    Espinosa, G.; Golzarri, J. I.; Fragoso, R.; Vazquez L, C.; Saad, A. F.; El-Namrouty, A. A.; Fujii, M.

    2012-01-01

    Among several different techniques to analyze material surface, the use of Atomic Force Microscope is one of the finest method. As we know, the sensitivity to detect energetic ions is extremely affected during the storage time and conditions of the polymeric material used as a nuclear track detector. On the basis of the surface analysis of several track detector materials, we examined the detection sensitivity of these detectors exposed to alpha particles. The preliminary results revealed that the ageing effect on its sensitivity is very strong, that need to be considered on the routine applications or research experiments. The results are consistent with the experimental data in the literature. (Author)

  3. Solid state nuclear track detectors and their application in industrial health, radiological and environmental protection

    International Nuclear Information System (INIS)

    Urban, M.

    1993-09-01

    Passive Solid State Nuclear Track Detectors are electrically non conductive solids, mainly used for the registration of α-particles and neutron induced recoils. The stability of the particle tracks in the solid allow longer integration periods, what is essential for the measurement of small, time variant radiation exposures. This report gives an overview on non-photographic track detectors, their processing, dosimetric properties and examples for their application in industrial health, radiological and environmental protection. (orig.) [de

  4. A TPC-like readout method for high precision muon-tracking using GEM-detectors

    Energy Technology Data Exchange (ETDEWEB)

    Flierl, Bernhard; Biebel, Otmar; Bortfeldt, Jonathan; Hertenberger, Ralf; Klitzner, Felix; Loesel, Philipp; Mueller, Ralph [Ludwig-Maximilians-Universitaet Muenchen (Germany); Zibell, Andre [Julius-Maximilians-Universitaet Wuerzburg (Germany)

    2016-07-01

    Gaseous electron multiplier (GEM) detectors are well suited for tracking of charged particles. Three dimensional tracking in a single layer can be achieved by application of a time-projection-chamber like readout mode (μTPC), if the drift time of the electrons is measured and the position dependence of the arrival time is used to calculate the inclination angle of the track. To optimize the tracking capabilities for ion tracks drift gas mixtures with low drift velocity have been investigated by measuring tracks of cosmic muons in a compact setup of four GEM-detectors of 100 x 100 x 6 mm{sup 3} active volume each and an angular acceptance of -25 to 25 . The setup consists of three detectors with two-dimensional strip readout layers of 0.4 mm pitch and one detector with a single strip readout layer of 0.25 mm pitch. All strips are readout by APV25 frontend boards and the amplification stage in the detectors consists of three GEM-foils. Tracks are reconstructed by the μTPC-method in one of the detectors and are then compared to the prediction from the other three detectors defined by the center of charge in every detector. We report our study of Argon and Helium based noble gas mixtures with carbon-dioxide as quencher.

  5. Status and trends of solid state track detector use in radiation protection monitoring

    International Nuclear Information System (INIS)

    Doerschel, B.

    1980-01-01

    The characteristic properties of solid state track detectors allow them to be used for determining the radiation fields of charged and uncharged particles and, consequently, for solving some problems involved in radiation protection monitoring. Aptitude of various detector materials is investigated on the basis of the track formation mechanism taking into account the properties of the particles to be detected. Use of these detectors in radiation protection monitoring presumes appropriate methods of intensifying the latent tracks, which are discussed as a function of various physical parameters. Readout methods of solid state track detectors are based on variations in detector properties determined by number and size of particle tracks in the detector. The choice of a special readout method, among other things, depends on the purpose, detector material, and pretreatment of the detectors. The most prospective methods are described and investigated with respect to their possible use in various fields of radiation protection monitoring. The trends of development of the application of solid state track detectors in radiation protection monitoring are discussed, using some typical applications as examples. (author)

  6. Timing of tertiary extension in the Southern Canadian Cordillera: constraints from fission-track analysis in the Shuswap metamorphic complex

    International Nuclear Information System (INIS)

    Lorencak, M.; Seward, D.; Burg, J.-P.

    1999-01-01

    Full text: Nine zircon and eighteen apatite fission-track analyses have been made in order to determine the low temperature cooling history of the Shuswap metamorphic core complex, western Canada. The zircons vary in apparent age from 53.9 ± 5.6 to 37.5 ± 5.0 Ma and the apatites from 48.5 ± 3.2 to 27.7 ± 3.4 Ma. In the footwall of the detachment faults defining the core complex, the cooling histories show a similarity until temperatures of ∼250 C were reached at about 45 Ma. From then on, activity on two normal faults, the Columbia River Fault and the Victor Creek Fault, controlled the regional cooling pattern. The ages and the combination of ages fall into four groups and on the basis of the fission-track data, we suggest that the region can now be divided into four thermotectonic units which are the result of differing tectonic controls during regional extension. Additionally, a complete cooling history of the Shuswap core complex can now be reconstructed, using constraints from U-Pb, Rb-Sr and K-Ar age data from several authors as well as the fission track results presented here. Copyright (1999) Geological Society of Australia

  7. Comparison through fission-track analysis of portions of Australia and Antarctica adjacent prior to continental drift

    International Nuclear Information System (INIS)

    Stump, E.; Fitzgerald, P.G.

    1990-01-01

    Australia and Antarctica have been reconstructed by the matching of three terranes in western Victoria with three terranes in northern Victoria Land. Apparent fission-track ages from granitic rocks of these matched regions are compared. In western Victoria, Australia, data reflect a history of slow cooling following intrusion in early to middle Paleozoic time. In northern Victoria Land, Antarctica, a complex history of cooling and uplift is indicated, with uplift of the present-day mountains commencing approximately 50 Ma. Fission tracks in apatites from most samples from northern Victoria Land were completely re-set to zero by the thermal effects of Jurassic tholeiitic magmatism. Apatite in three samples however, predate the Jurassic and were only partially re-set by this event. Apparent sphene fission-track ages indicate that the three terranes in northern Victoria Land have shared a common thermal history since the Devonian. With the exception of one small area in western Victoria, neither western Victoria nor northern Victoria Land data show a clear influence of rifting and breakup in the late Cretaceous. Overall, the data indicate that once the breakup of Australia and Antarctica had occurred, their thermal and tectonic histories evolved independently along differing paths. (author)

  8. Fission track ages on apatite of Bergell rocks from central Alps and Bergell boulders in Oligocene sediments

    International Nuclear Information System (INIS)

    Wagner, G.A.; Miller, D.S.

    1979-01-01

    Previous radiometric dating studies indicated that the Bergell region, in contrast to other regions of the Central Alps, experienced an early, rapid uplift, but with decreasing rate. Furthermore, there is also a geological record of the early uplift history of the Bergell granite by the existence of boulders which were derived from this granite and which occur in the Late Oligocene sediments of the Po plain. In this work the uplift history of the Bergell is studied in more detail by fission track dating of additional apatites from the Bergell region. Secondly, by determining apatite fission track ages the granitic boulders of the Po plain can be re-assigned to their original vertical position within the Bergell intrusive before erosion removed them in Late Oligocene time. A rather conservative estimate replaces them 6 km above the present morphology of the Bergell massif. Thus, the thickness of the Bergell granite must have been at least 8 km. Generally, fission track studies on boulders may become an important tool to study the vertical extent of mountain chains during the geological past. (Auth.)

  9. Identification of the source of manufacture of obsidian through the dating with the method of fission track

    International Nuclear Information System (INIS)

    Arias, C.; Bigazzi, G.; Bonadonna, F.P.; Radi, G.; Bernardes, C.; Hadler Neto, J.C.; Lattes, C.M.G.; Araya, A.M.O.; Oliveira, J.X.

    1986-01-01

    Identification of the source of manufacture of obsidian through the dating with the method of fission track. After a brief description of fission track dating method and of the problems related to its application to volcanic glasses, we show and discuss data about obsidians of geological origin from Mediterranean basin and Latin America and of archaeological origin found in prehistoric sites from Italian peninsula. The analysis of the results shows the excellent performance of fission track method to identify the provenance of obsidians of archaeological origin, provided important constributions both from the methodological pointo of view-excellent agreement between the two correction techniques of apparent ages, size-correction technique and plateau age -, as from the archaeological point of view - we could identify four possible sources of provenance in Italy, the obsidian from Monte Arci, Sardinia, the obsidian from Pahnarola island, the obsidian from Gabelloto, Lipari island and the obsidian from Balata dei Turchi, Pantelleria island; and it ca be shown that Lipari obsidian began to be used at a very antique phase of neolithic period. The data about Latin American samples, though fragmented, constitute in an inicial study promissing perpectives as it can be observed by the comparisions made with the data published by others authors about geologic and archaeologic samples from the same area. (Author) [pt

  10. Plastic nuclear track detectors as high x-ray and gamma dosimeters

    International Nuclear Information System (INIS)

    Chong Chon Sing

    1995-01-01

    A brief review of recent studies on the effects of high doses of x-ray and gamma ray on the track registration properties of several plastic track detectors is presented. The bulk etching rates and the etched track sizes have been found to increase with the dose in the range up to 100 Mrad. These results suggest that the changes in track registration characteristics can be employed as an index of the radiation dose in the megarad region. In particular, recent results on the effect of X-ray irradiation on two types of cellulose nitrate track detectors obtained in our laboratory are reported in this paper. (author)

  11. Early Inner Detector Tracking Performance in the 2015 data at $\\sqrt s$ = 13 TeV

    CERN Document Server

    The ATLAS collaboration

    2015-01-01

    This note summarises the studies undertaken to recommend benchmark values and systematic uncertainties for various aspects of the ATLAS Inner Detector tracking based on $\\sqrt{s}= 13$ TeV proton-proton collisions from the Large Hadron Collider Run 2 data. The track reconstruction efficiency, fake rate, and related systematic uncertainties are presented for two different track quality selections, along with the impact parameter resolution and the alignment weak mode systematic uncertainities. These recommendations apply to physics analyses using Inner Detector tracks in Run 2 data and are important inputs for other objects based on tracks.

  12. Liquid nitrogen enhancement of alpha particle tracks in a polycarbonate detector

    International Nuclear Information System (INIS)

    Pilione, L.J.

    1977-01-01

    Makrofol-E polycarbonate detectors were exposed to 1 to 3 MeV alpha particles and subsequently immersed in liquid nitrogen for various periods of time. The influence of the liquid nitrogen on the track recording properties of the detector has been found by measuring the track densities and diameters. Track densities increase with immersion time with a maximum gain of approximately 9% after 1200 min in liquid nitrogen. Track enhancement decreases with waiting time between the end of alpha particle exposure and the beginning of liquid nitrogen immersion. Track diameters decrease with time after passage of the particles and this process is accelerated by immersion in liquid nitrogen. (author)

  13. Trace quantities of uranium in some indian chewing tobaccos as determined by fission track analysis

    International Nuclear Information System (INIS)

    Rana, N.P.S.; Singh, P.; Azam, A.; Naqvi, A.H.; Srivastava, D.S.

    1996-01-01

    The sandwiched pellet technique using Makrofol-E plastic track detectors has been employed to determine trace quantities of uranium in nine brands of flavored chewing tobaccos consumed by the Indian population. In this technique the nuclear reaction, 235 U(n,f), is used for the quantitative estimation of uranium. The maximum value of uranium (1.88 ppm) has been found in raw tobacco leaves (Surti), while the minimum (0.13 ppm) in Tulsi (Double Zero brand). Other seven brands showed intermediate values of U-contents which are also reported in this paper. These values are compared with the U-contents reported in the literature for other forms of tobaccos. (author). 9 refs., 2 figs., 1 tab

  14. The forward detector of the ANKE spectrometer. Tracking system and its use in data analysis

    International Nuclear Information System (INIS)

    Dymov, S.; Erven, W.; Kacharava, A.

    2004-01-01

    The tracking system of the forward detector of the ANKE magnetic spectrometer at the internal beam of the accelerator COSY (Juelich, Germany) is described. Data analysis procedures, including track search and momentum reconstruction, are presented, and the performance of the tracking system is illustrated with the use of experimental data

  15. Mesozoic and Cenozoic uplift and exhumation of the Bogda Mountain, NW China: Evidence from apatite fission track analysis

    Directory of Open Access Journals (Sweden)

    Wenhao Tang

    2015-07-01

    Full Text Available Apatite fission track (AFT analysis on samples collected from a Paleozoic series is used to constrain the cooling history of the Bogda Mountain, northwest China. AFT ages range from 136.2 to 85.6 Ma and are younger than rock depositional ages and the mean confined track lengths (11.0–13.2 μm mostly showing unimodal distribution are shorten, indicating significant track-annealing. Thermal histories modeling based on the distribution of fission-track lengths combined with the regional geological data show that two rapid cooling phases occurred in the latest Jurassic–early Cretaceous and the Oligocene–Miocene. Those new data together with previous published data show that the AFT ages become younger from the southwest to northeast in the western Bogda Mountain and its adjacent areas. The fission-track ages of the southwest area are relatively older (>100 Ma, recording the earlier rapid uplift phase during the late Jurassic–Cretaceous, while the ages in the north piedmont of the Bogda Mountain (namely the northeast part are younger (<60 Ma, mainly reflecting the later rapid uplift phase in the Oligocene–Miocene. The trend of younger AFT ages towards the northeast might be explained by post-Cretaceous large-scale crustal tilting towards the southwest. In the thrust fault-dominated northern limbs of the Bogda Mountain, AFT ages reveal a discontinuous pattern with age-jumps across the major fault zones, showing a possible strata tilting across each thrust faults due to the thrust ramps during the Cenozoic. The two rapid uplift stages might be related to the accretion and collision in the southern margin of the Asian continent during the late Jurassic and late Cenozoic, respectively.

  16. Combined performance tests before installation of the ATLAS Semiconductor and Transition Radiation Tracking Detectors

    Czech Academy of Sciences Publication Activity Database

    Abat, E.; Abdesselam, A.; Andy, T.N.; Böhm, Jan; Šťastný, Jan

    2008-01-01

    Roč. 3, - (2008), P08003/1-P08003/67 ISSN 1748-0221 R&D Projects: GA MŠk LA08032; GA MŠk 1P04LA212 Institutional research plan: CEZ:AV0Z10100502 Keywords : solid state detectors * particle tracking detectors * large detector systems for particle and astroparticle physics * transition radiation detectors Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 0.333, year: 2008

  17. Tracking in full Monte Carlo detector simulations of 500 GeV e+e- collisions

    International Nuclear Information System (INIS)

    Ronan, M.T.

    2000-01-01

    In full Monte Carlo simulation models of future Linear Collider detectors, charged tracks are reconstructed from 3D space points in central tracking detectors. The track reconstruction software is being developed for detailed physics studies that take realistic detector resolution and background modeling into account. At this stage of the analysis, reference tracking efficiency and resolutions for ideal detector conditions are presented. High performance detectors are being designed to carry out precision studies of e + e - annihilation events in the energy range of 500 GeV to 1.5 TeV. Physics processes under study include Higgs mass and branching ratio measurements, measurement of possible manifestations of Supersymmetry (SUSY), precision Electro-Weak (EW) studies and searches for new phenomena beyond their current expectations. The relatively-low background machine environment at future Linear Colliders will allow precise measurements if proper consideration is given to the effects of the backgrounds on these studies. In current North American design studies, full Monte Carlo detector simulation and analysis is being used to allow detector optimization taking into account realistic models of machine backgrounds. In this paper the design of tracking software that is being developed for full detector reconstruction is discussed. In this study, charged tracks are found from simulated space point hits allowing for the straight-forward addition of background hits and for the accounting of missing information. The status of the software development effort is quantified by some reference performance measures, which will be modified by future work to include background effects

  18. Study of the behavior of automatic track detectors for radon determination

    International Nuclear Information System (INIS)

    Moreno C, A.

    1997-01-01

    Both the alpha decay and the alpha and beta emitting radon daughters, may affect the living cells. In this thesis, experiments have been performed to study the response of environmental radon using different alpha particle detectors. A study was performed both in the laboratory and in the field of two kinds of detectors: a) Passive solid state nuclear track detectors, LR 115 type II, capable to integrate the alpha particles in a given period of time and, b) an automatic active detector, Clipperton, that continuously accumulate the alpha counting from radon decay. LR-115 track detectors were exposed in the laboratory to alpha particles from a radioactive source and a controlled radon atmosphere. The detectors were also exposed to electrons from an electron accelerator. The number of alpha tracks in the detectors were evaluated with two kinds of spark counters. The response of the track detectors as a function of the number of alpha tracks showed a reproducibility of 92%, and the effect of electron doses showed that the bulk etching velocity varied as a function of the electron dose. Additionally some changes were introduced in an SSNTD exchanger, exposed to the radon chamber in order to reduce the background in the non exposed positions. A conversion factor of 0.016 tracks/cm 2 . 10h per Bq/m 3 was obtained. The response of the two spark counters was similar. Field soil radon determinations were performed with track detectors during 11 months and with the active detector during 5 months with exposures each month and each hour respectively. When calculated for the same time periods exposure the response of both systems was similar. However differences were quite striking in the patterns of short and long term exposure periods since short term fluctuations are explicitly shown with the active detector while integrated within the passive one. (Author)

  19. Fission-track dating of South American natural glasses: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Bigazzi, G. [Istituto di Geoscienze e Georisorse, C.N.R., Via G. Moruzzi, 1, 56124 Pisa (Italy)]. E-mail: g.bigazzi@igg.cnr.it; Hadler Neto, J.C. [Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-970 Campinas SP (Brazil); Iunes, P.J. [Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-970 Campinas SP (Brazil); Osorio Araya, A.M. [Departamento de Fisica, Quimica e Biologia, Universidade do Estado de Sao Paulo, UNESP, 19060-900 Presidente Prudente SP (Brazil)

    2005-12-01

    Although many glass-bearing horizons can be found in South American volcanic complexes or sedimentary series, only a relatively few tephra and obsidian-bearing volcanic fields have been studied using the fission-track (FT) dating method. Among them, the volcanics located in the Sierra de Guamani (east of Quito, Ecuador) were studied by several authors. Based upon their ages, obsidians group into three clusters: (1) very young obsidians, {approx}0.2Ma old (2) intermediate-age obsidians, {approx}0.4-{approx}0.8Ma old, and (3) older obsidians, {approx}1.4-{approx}1.6Ma old. The FT method is also an efficient alternative technique for identification of the sources of prehistoric obsidian artefacts. Provenance studies carried out in South America have shown that the Sierra de Guamani obsidian occurrences were important sources of raw material for tool making during pre-Columbian times. Glasses originated from these sources were identified in sites distributed over relatively wide areas of Ecuador and Colombia. Only a few systematic studies on obsidians in other sectors were carried out. Nevertheless, very singular glasses have been recognised in South America, such as Macusanite (Peru) and obsidian Quiron (Argentina), which are being proposed as additional reference materials for FT dating. Analyses of tephra beds interstratified with sedimentary deposits revealed the performance of FT dating in tephrochronological studies. A remarkable example is the famous deposit outcropping at Farola Monte Hermoso, near Bahia Blanca (Buenos Aires Province), described for the first time by the middle of the 19th century by Charles Darwin. Considering the large number of volcanic glasses that were recognised in volcanic complexes and in sedimentary series, South America is a very promising region for the application of FT dating. The examples given above show that this technique may yield important results in different disciplinary fields.

  20. Fission-track constraints on the thermal and tectonic evolution of the Apuseni Mountains (Romania)

    Science.gov (United States)

    Kounov, Alexandre; Schmid, Stefan M.

    2013-01-01

    New zircon and apatite fission-track (FT) data, including apatite thermal modelling, are combined with an extensive literature survey and reconnaissance-type structural fieldwork in the Eastern Apuseni Mountains. This leads to a better understanding of the complex structural and thermal history of a key area at the boundary between two megatectonic units in the Balkan peninsula, namely the Tisza and Dacia Mega-Units. Following Late Jurassic obduction of the Transylvanian ophiolites onto a part of the Dacia Mega-Unit, that is, the Biharia nappe system, both units were buried to a minimum of 8 km during late Early Cretaceous times when these units were underthrust below the Tisza Mega-Unit consisting of the present-day Codru and Bihor nappe systems. Tisza formed the upper plate during Early Cretaceous (`Austrian') east-facing orogeny. Turonian to Campanian zircon FT cooling ages (95-71 Ma) from the Bihor and Codru nappe systems and the Biharia and Baia de Arieş nappes (at present the structurally lowest part of the Dacia Mega-Unit) record exhumation that immediately followed a second Cretaceous-age (i.e. Turonian) orogenic event. Thrusting during this overprinting event was NW-facing and led to the overall geometry of the present-day nappe stack in the Apuseni Mountains. Zircon FT ages, combined with thermal modelling of the apatite FT data, show relatively rapid post-tectonic cooling induced by a third shortening pulse during the latest Cretaceous (`Laramian' phase), followed by slower cooling across the 120°-60 °C temperature interval during latest Cretaceous to earliest Paleogene times (75-60 Ma). Cenozoic-age slow cooling (60-40 Ma) was probably related to erosional denudation postdating `Laramian' large-scale updoming.

  1. Fission-track dating of South American natural glasses: an overview

    International Nuclear Information System (INIS)

    Bigazzi, G.; Hadler Neto, J.C.; Iunes, P.J.; Osorio Araya, A.M.

    2005-01-01

    Although many glass-bearing horizons can be found in South American volcanic complexes or sedimentary series, only a relatively few tephra and obsidian-bearing volcanic fields have been studied using the fission-track (FT) dating method. Among them, the volcanics located in the Sierra de Guamani (east of Quito, Ecuador) were studied by several authors. Based upon their ages, obsidians group into three clusters: (1) very young obsidians, ∼0.2Ma old (2) intermediate-age obsidians, ∼0.4-∼0.8Ma old, and (3) older obsidians, ∼1.4-∼1.6Ma old. The FT method is also an efficient alternative technique for identification of the sources of prehistoric obsidian artefacts. Provenance studies carried out in South America have shown that the Sierra de Guamani obsidian occurrences were important sources of raw material for tool making during pre-Columbian times. Glasses originated from these sources were identified in sites distributed over relatively wide areas of Ecuador and Colombia. Only a few systematic studies on obsidians in other sectors were carried out. Nevertheless, very singular glasses have been recognised in South America, such as Macusanite (Peru) and obsidian Quiron (Argentina), which are being proposed as additional reference materials for FT dating. Analyses of tephra beds interstratified with sedimentary deposits revealed the performance of FT dating in tephrochronological studies. A remarkable example is the famous deposit outcropping at Farola Monte Hermoso, near Bahia Blanca (Buenos Aires Province), described for the first time by the middle of the 19th century by Charles Darwin. Considering the large number of volcanic glasses that were recognised in volcanic complexes and in sedimentary series, South America is a very promising region for the application of FT dating. The examples given above show that this technique may yield important results in different disciplinary fields

  2. Tracking Performance in High Multiplicity Environment for the CLIC ILD Detector

    CERN Document Server

    Killenberg, M

    2012-01-01

    We report on the tracking efficiency and the fraction of badly reconstructed tracks in the CLIC ILD detector for high multiplicity events (tt ̄@3 TeV) with and without the presence of γγ →hadrons background. They have been studied for the silicon tracking, the TPC tracking and the so called FullLDC tacking, which combines silicon and TPC measurements.

  3. The effects of sunlight exposure on the neutron response of CN-85 track detector

    International Nuclear Information System (INIS)

    Ahmad, N.; Mirza, N.M.; Mirza, S.K.; Tufail, M.

    1996-01-01

    The effect of sunlight exposure on the neutron response of CN-85 track detectors has been studied. It has been observed that the response during the first 28 days of sunlight exposure is slightly enhanced (10%) and then deceases continuously with increase in the sunlight exposure. After 84 days of sunlight exposure the response of the exposed detector relative to an unexposed detector is only 22%. It is also observed that the response can not be maintained by wrapping the CN-85 etch track detectors in typewriter black carbon papers if they are exposed to sunlight. (author)

  4. The FCMM, a Fastbus Control and Memory Module for readout of the DELPHI SAT track detector

    International Nuclear Information System (INIS)

    Wikne, J.C.; Skaali, B.

    1990-02-01

    The Small Angle Tagger (SAT) in the DELPHI experiment at CERN concists of detector units placed close to the beam on both sides of the interaction point. The track detector part of the SAT is built of Si-strip detectors where position can be measured to an accurancy of 1 mm in the radial direction. A specially developed Fastbus module for reading and front end buffering of the data from the track detector is decribed in the report. The description is intended as a complete technical manual for the module. 13 refs.; 27 figs

  5. The solid state track detectors for α-particles angular distribution measurements

    International Nuclear Information System (INIS)

    Bakr, M.H.S.

    1978-01-01

    The solid state track detectors technique is described in details from the point of view of applying them in nuclear reactions research. Using an optimum developing solution, the etching rate of polycarbonate detector was found to be 10.5 μ/hour. The energy resolution of this detector was estimated using 241 Am α-source at α-energies between 1 and 3 Mev. The scattering chamber designed for angular distribution measurements using solid state track detectors is described. A special schematic normograph for range-energy-degrading foils relation is given

  6. Solid State Track Recorder fission rate measurements in low power light water reactor pressure vessel mockups

    International Nuclear Information System (INIS)

    Ruddy, F.H.; Roberts, J.H.; Kellogg, L.S.

    1985-01-01

    The results of extensive SSTR measurements made at the Pool Critical Assembly (PCA) facility at Oak Ridge National Laboratory have been reported previously. Measurements were made at key locations in PCA which is an idealized mockup of the water gap, thermal shield, pressure vessel geometry of a light water reactor. Recently, additional SSTR fission rate measurements have been carried out for 237-Np, 238-U, and 235-U in key locations in the NESTOR Shielding and Dosimetry Improvement Program (NESDIP) mockup facility located at Winfrith, England. NESDIP is a replica of the PCA facility, and comparisons will be made between PCA and NESDIP measurements. The results of measurements made at the engineering mockup at the VENUS critical assembly at CEN/SCK, Mol, Belgium will also be reported. Measurements were made at selected radial and azimuthal locations in VENUS, which models the in-core and near-core regions of a pressurized water reactor. Comparisons of absolute SSTR fission rates with absolute fission rates made with the Mol miniature fission chamber will be reported. Absolute fission rate comparisons have also been made between the NBS fission chamber, radiometric fission foils, and SSTRs, and these results will be summarized

  7. PixTrig: a Level 2 track finding algorithm based on pixel detector

    CERN Document Server

    Baratella, A; Morettini, P; Parodi, F

    2000-01-01

    This note describes an algorithm for track search at Level 2 based on pixel detector. Using three pixel clusters we can produce a reconstruction of the track parameter in both z and R-phi plane. These track segments can be used as seed for more sophisticated track finding algorithms or used directly, especially when impact parameter resolution is crucial. The algorithm efficiency is close to 90% for pt > 1 GeV/c and the processing time is small enough to allow a complete detector reconstruction (non RoI guided) within the Level 2 processing.

  8. High temperature annealing of fission tracks in fluorapatite, Santa Fe Springs oil field, Los Angeles Basin, California

    Science.gov (United States)

    Naeser, Nancy D.; Crowley, Kevin D.; McCulloh, Thane H.; Reaves, Chris M.; ,

    1990-01-01

    Annealing of fission tracks is a kinetic process dependent primarily on temperature and to a laser extent on time. Several kinetic models of apatite annealing have been proposed. The predictive capabilities of these models for long-term geologic annealing have been limited to qualitative or semiquantitative at best, because of uncertainties associated with (1) the extrapolation of laboratory observations to geologic conditions, (2) the thermal histories of field samples, and (3) to some extent, the effect of apatite composition on reported annealing temperatures. Thermal history in the Santa Fe Springs oil field, Los Angeles Basin, California, is constrained by an exceptionally well known burial history and present-day temperature gradient. Sediment burial histories are continuous and tightly constrained from about 9 Ma to present, with an important tie at 3.4 Ma. No surface erosion and virtually no uplift were recorded during or since deposition of these sediments, so the burial history is simple and uniquely defined. Temperature gradient (???40??C km-1) is well established from oil-field operations. Fission-track data from the Santa Fe Springs area should thus provide one critical field test of kinetic annealing models for apatite. Fission-track analysis has been performed on apatites from sandstones of Pliocene to Miocene age from a deep drill hole at Santa Fe Springs. Apatite composition, determined by electron microprobe, is fluorapatite [average composition (F1.78Cl0.01OH0.21)] with very low chlorine content [less than Durango apatite; sample means range from 0.0 to 0.04 Cl atoms, calculated on the basis of 26(O, F, Cl, OH)], suggesting that the apatite is not unusually resistant to annealing. Fission tracks are preserved in these apatites at exceptionally high present-day temperatures. Track loss is not complete until temperatures reach the extreme of 167-178??C (at 3795-4090 m depth). The temperature-time annealing relationships indicated by the new data

  9. 2. International workshop Solid state nuclear track detectors and their applications

    International Nuclear Information System (INIS)

    Perelygin, V.P.

    1992-01-01

    The 2. Workshop on Solid state nuclear track detectors (SSNTD) held in Dubna, 24-26 Mar 1992. Possibilities of SSNTD applications in the fields of high and low energy physics, dosimetry and radioecology were discussed

  10. Radon diffusion studies in some building materials using solid state nuclear track detectors

    CERN Document Server

    Singh, S; Singh, B; Singh, J

    1999-01-01

    LR-115 plastic track detector has been used to study radon diffusion through some building materials, viz. cement, soil, marble chips, sand and lime as well as air. Diffusion constant and diffusion length is calculated for all these materials.

  11. Development of alpha spectroscopy method with solid state nuclear track detector using aluminium thin films

    Energy Technology Data Exchange (ETDEWEB)

    Dwaikat, N., E-mail: ndwaikat@kfupm.edu.sa [King Fahd University of Petroleum and Minerals, College of Sciences, Department of Physics, Dhahran 31261 (Saudi Arabia)

    2015-10-15

    This work presents the development of alpha spectroscopy method with Solid-state nuclear track detectors using aluminum thin films. The resolution of this method is high, and it is able to discriminate between alpha particles at different incident energy. It can measure the exact number of alpha particles at specific energy without needing a calibration of alpha track diameter versus alpha energy. This method was tested by using Cf-252 alpha standard source at energies 5.11 MeV, 3.86 MeV and 2.7 MeV, which produced by the variation of detector -standard source distance. On front side, two detectors were covered with two Aluminum thin films and the third detector was kept uncovered. The thickness of Aluminum thin films was selected carefully (using SRIM 2013) such that one of the films will block the lower two alpha particles (3.86 MeV and 2.7 MeV) and the alpha particles at higher energy (5.11 MeV) can penetrate the film and reach the detectors surface. The second thin film will block alpha particles at lower energy of 2.7 MeV and allow alpha particles at higher two energies (5.11 MeV and 3.86 MeV) to penetrate and produce tracks. For uncovered detector, alpha particles at three different energies can produce tracks on it. For quality assurance and accuracy, the detectors were mounted on thick enough copper substrates to block exposure from the backside. The tracks on the first detector are due to alpha particles at energy of 5.11 MeV. The difference between the tracks number on the first detector and the tracks number on the second detector is due to alpha particles at energy of 3.8 MeV. Finally, by subtracting the tracks number on the second detector from the tracks number on the third detector (uncovered), we can find the tracks number due to alpha particles at energy 2.7 MeV. After knowing the efficiency calibration factor, we can exactly calculate the activity of standard source. (Author)

  12. Development of alpha spectroscopy method with solid state nuclear track detector using aluminium thin films

    International Nuclear Information System (INIS)

    Dwaikat, N.

    2015-10-01

    This work presents the development of alpha spectroscopy method with Solid-state nuclear track detectors using aluminum thin films. The resolution of this method is high, and it is able to discriminate between alpha particles at different incident energy. It can measure the exact number of alpha particles at specific energy without needing a calibration of alpha track diameter versus alpha energy. This method was tested by using Cf-252 alpha standard source at energies 5.11 MeV, 3.86 MeV and 2.7 MeV, which produced by the variation of detector -standard source distance. On front side, two detectors were covered with two Aluminum thin films and the third detector was kept uncovered. The thickness of Aluminum thin films was selected carefully (using SRIM 2013) such that one of the films will block the lower two alpha particles (3.86 MeV and 2.7 MeV) and the alpha particles at higher energy (5.11 MeV) can penetrate the film and reach the detectors surface. The second thin film will block alpha particles at lower energy of 2.7 MeV and allow alpha particles at higher two energies (5.11 MeV and 3.86 MeV) to penetrate and produce tracks. For uncovered detector, alpha particles at three different energies can produce tracks on it. For quality assurance and accuracy, the detectors were mounted on thick enough copper substrates to block exposure from the backside. The tracks on the first detector are due to alpha particles at energy of 5.11 MeV. The difference between the tracks number on the first detector and the tracks number on the second detector is due to alpha particles at energy of 3.8 MeV. Finally, by subtracting the tracks number on the second detector from the tracks number on the third detector (uncovered), we can find the tracks number due to alpha particles at energy 2.7 MeV. After knowing the efficiency calibration factor, we can exactly calculate the activity of standard source. (Author)

  13. Measuring variation of indoor radon concentration using bare nuclear tracks detectors, scintillation counters and surface barrier detectors

    International Nuclear Information System (INIS)

    Ishak, I.; Mahat, R.H.; Amin, Y.M.

    1996-01-01

    Bare LRI 15 nuclear track detectors , scintillators counter and surface barrier detectors were used to measured the indoor radon concentration in various location within two rooms. Spatial variation of the radon concentration is caused by positioning of the door, windows, furniture, cracks in the building and also distances from floor, wall and ceiling. It is found that the change in temperature are causing radon concentration to increase at certain time of the day

  14. Charged projectile spectrometry using solid-state nuclear track detector of the PM-355 type

    Directory of Open Access Journals (Sweden)

    Malinowska Aneta

    2015-09-01

    Full Text Available To use effectively any radiation detector in high-temperature plasma experiments, it must have a lot of benefits and fulfill a number of requirements. The most important are: a high energy resolution, linearity over a wide range of recorded particle energy, high detection efficiency for these particles, a long lifetime and resistance to harsh conditions existing in plasma experiments and so on. Solid-state nuclear track detectors have been used in our laboratory in plasma experiments for many years, but recently we have made an attempt to use these detectors in spectroscopic measurements performed on some plasma facilities. This paper presents a method that we used to elaborate etched track diameters to evaluate the incident projectile energy magnitude. The method is based on the data obtained from a semiautomatic track scanning system that selects tracks according to two parameters, track diameter and its mean gray level.

  15. Completely automated measurement facility (PAVICOM) for track-detector data processing

    CERN Document Server

    Aleksandrov, A B; Feinberg, E L; Goncharova, L A; Konovalova, N S; Martynov, A G; Polukhina, N G; Roussetski, A S; Starkov, NI; Tsarev, V A

    2004-01-01

    A review of technical capabilities and investigations performed using the completely automated measuring facility (PAVICOM) is presented. This very efficient facility for track-detector data processing in the field of nuclear and high-energy particle physics has been constructed in the Lebedev physical institute. PAVICOM is widely used in Russia for treatment of experimental data from track detectors (emulsion and solid-state trackers) in high- and low-energy physics, cosmic ray physics, etc. PAVICOM provides an essential improvement of the efficiency of experimental studies. In contrast to semi-automated microscopes widely used until now, PAVICOM is capable of performing completely automated measurements of charged particle tracks in nuclear emulsions and track detectors without employing hard visual work. In this case, track images are recorded by CCD cameras and then are digitized and converted into files. Thus, experimental data processing is accelerated by approximately a thousand times. Completely autom...

  16. The Siegen automatic measuring system for nuclear track detectors: new developments

    International Nuclear Information System (INIS)

    Noll, A.; Rusch, G.; Roecher, H.; Dreute, J.; Heinrich, W.

    1988-01-01

    Starting ten years ago we developed completely automatic scanning and measuring systems for nuclear track detectors. In this paper we describe some new developments. Our autofocus systems based on the contrast of the video picture and on a laser autofocus have been improved in speed and in reliability. Based on new algorithms, faster programs have been developed to scan for nuclear tracks in plastic detectors. Methods for separation of overlapping tracks have been improved. Interactive programs for track measurements have been developed which are very helpful for space bio-physics experiments. Finally new methods for track measurements in nuclear emulsions irradiated with a beam perpendicular to the detector surface are described in this paper. (author)

  17. Cooling and denudation history of the Rokko area, southwest Japan, based on fission-track thermochronology

    International Nuclear Information System (INIS)

    Sueoka, Shigeru; Tagami, Takahiro; Tsutsumi, Hiroyuki; Hasebe, Noriko; Tamura, Akihiro; Arai, Shoji; Yamada, Ryuji; Matsuda, Tatsuo; Omura, Kentaro

    2010-01-01

    Quantitatively estimating denudation is generally difficult because it essentially involves the removal and loss of materials in situ. The denudation rate of mountainous areas in Japan has commonly been studied from the volume of sediment in a basin or catchment. Nonetheless, the availability of these methods is constrained spatially by upstream area and temporally by depositional age. In the last few decades, thermochronometric methods that evaluate thermal history using radiometric-dating methods have been used to evaluate the denudation and tectonic history of orogenic belts around the world. The advantages of thermochronometric methods are that we can calculate the denudation rate at each sampling point and that combining multiple methods and/or target minerals enables us to calculate denudation rates in multiple periods. However, thermochronometric methods have been applied to areas with extraordinarily high denudation rates in island arc areas such as Japan. Thus, the effectiveness of thermochronometric methods for estimating denudation rates in island arc areas has not been demonstrated. We applied apatite and zircon fission-track thermochronometry to granitic rock samples collected from outcrops and a borehole to estimate the tectonic history of the Rokko area, southwest Japan. Previous studies suggested that the Rokko Mountains have been uplifted by active faulting along their northern and southern margins during the Rokko movements, a Quaternary tectonic movement in the Kinki district. However, the tectonic history of the Rokko area prior to 1 Ma has not been revealed due to a lack of prevalent geologic markers. We estimated average denudation rates in various periods based on apatite and zircon FT ages and previously reported radiometric ages. We obtained denudation rates at about 0.04-0.10 mm/yr after about 30 Ma, 0.05-0.7 mm/yr during 50-30 Ma, 0.7-4.0 mm/yr during 70-50 Ma. The denudation rate after the deposition of the Kobe Group (36.9-30.4 Ma) is

  18. Apatite Fission-Track Analysis of the Middle Jurassic Todos Santos Formation from Chiapas, Mexico.

    Science.gov (United States)

    Abdullin, Fanis; Solé, Jesús; Shchepetilnikova, Valentina; Solari, Luigi; Ortega-Obregón, Carlos

    2014-05-01

    The Sierra de Chiapas (SCH), located in the south of Mexico, is a complex geological province that can be divided on four different lithological or tectonic areas: (1) the Chiapas Massif Complex (CMC); (2) the Central Depression; (3) the Strike-slip Fault Province, and (4) the Chiapas Fold-and-thrust Belt. The CMC mostly consists of Permian granitoids and meta-granitoids, and represents the basement of the SCH. During the Jurassic period red beds and salt were deposited on this territory, related to the main pulse of rifting and opening of the Gulf of Mexico. Most of the Cretaceous stratigraphy contains limestones and dolomites deposited on a marine platform setting during the postrift stage of the Gulf of Mexico rift. During the Cenozoic Era took place the major clastic sedimentation along the SCH. According the published low-temperature geochronology data (Witt et al., 2012), SCH has three main phases of thermo-tectonic history: (1) slow exhumation between 35 and 25 Ma, that affected mainly the basement (CMC) and is probably related to the migration of the Chortís block; (2) fast exhumation during the Middle-Late Miocene caused by strike-slip deformation that affects almost all Chiapas territory; (3) period of rapid cooling from 6 to 5 Ma, that affects the Chiapas Fold-and-thrust Belt, coincident with the landward migration of the Caribbean-North America plate boundaries. The two last events were the most significant on the formation of the present-day topography of the SCH. However, the stratigraphy of the SCH shows traces of the existence of earlier tectonic events. This study presents preliminary results of apatite fission-track (AFT) dating of sandstones from the Todos Santos Formation (Middle Jurassic). The analyses are performed with in situ uranium determination using LA-ICP-MS (e.g., Hasebe et al., 2004). The AFT data indicate that this Formation has suffered high-grade diagenesis (probably over 150 ºC) and the obtained cooling ages, about 70-60 Ma

  19. Nuclear Track Detector Characterization via Alpha-Spectrometry for Radioprotection Use

    Energy Technology Data Exchange (ETDEWEB)

    Morelli, D.; Imme, G.; Catalano, R. [Dipartimento di Fisica e Astronomia, Universita degli Studi di Catania, via S. Sofia, 64- 95123 Catania (Italy); Istituto Nazionale di Fisica Nucleare - Sezione di Catania, via S. Sofia, 64- 95123 Catania (Italy); Aranzulla, M. [Istituto Nazionale Geofisica e Vulcanologia - Sezione di Catania, piazza Roma, 2- 95127 Catania (Italy); Tazzer, A. L. Rosselli; Mangano, G. [Dipartimento di Fisica e Astronomia, Universita degli Studi di Catania, via S. Sofia, 64- 95123 Catania (Italy)

    2011-12-13

    Solid Nuclear Track Detectors (SNTDs), CR-39 type, are usually adopted to monitor radon gas concentrations. In order to characterize the detectors according to track geometrical parameters, detectors were irradiated inside a vacuum chamber by alpha particles at twelve energy values, obtained by different Mylar foils in front of a {sup 241}Am source. The alpha energy values were verified using a Si detector. After the exposure to the alpha particles, the detectors were chemically etched to enlarge the tracks, which were then analyzed by means of a semiautomatic system composed of an optical microscope equipped with a CCD camera connected to a personal computer to store images. A suitable routine analyzed the track parameters: major and minor axis length and mean grey level, allowing us to differentiate tracks according to the incident alpha energy and then to individuate the discrimination factors for radon alpha tracks. The combined use of geometrical and optical parameters allows one to overcome the ambiguity in the alpha energy determination due to the non-monotonicity of each parameter versus energy. After track parameter determination, a calibration procedure was performed by means of a radon chamber. The calibration was verified through an inter-comparing survey.

  20. A novel generic framework for track fitting in complex detector systems

    International Nuclear Information System (INIS)

    Hoeppner, C.; Neubert, S.; Ketzer, B.; Paul, S.

    2010-01-01

    This paper presents a novel framework for track fitting which is usable in a wide range of experiments, independent of the specific event topology, detector setup, or magnetic field arrangement. This goal is achieved through a completely modular design. Fitting algorithms are implemented as interchangeable modules. At present, the framework contains a validated Kalman filter. Track parameterizations and the routines required to extrapolate the track parameters and their covariance matrices through the experiment are also implemented as interchangeable modules. Different track parameterizations and extrapolation routines can be used simultaneously for fitting of the same physical track. Representations of detector hits are the third modular ingredient to the framework. The hit dimensionality and orientation of planar tracking detectors are not restricted. Tracking information from detectors which do not measure the passage of particles in a fixed physical detector plane, e.g. drift chambers or TPCs, is used without any simplification. The concept is implemented in a light-weight C++ library called GENFIT, which is available as free software.

  1. A novel generic framework for track fitting in complex detector systems

    Energy Technology Data Exchange (ETDEWEB)

    Hoeppner, C., E-mail: christian.hoeppner@cern.c [Technische Universitaet Muenchen, Physik Department, 85748 Garching (Germany); Neubert, S.; Ketzer, B.; Paul, S. [Technische Universitaet Muenchen, Physik Department, 85748 Garching (Germany)

    2010-08-21

    This paper presents a novel framework for track fitting which is usable in a wide range of experiments, independent of the specific event topology, detector setup, or magnetic field arrangement. This goal is achieved through a completely modular design. Fitting algorithms are implemented as interchangeable modules. At present, the framework contains a validated Kalman filter. Track parameterizations and the routines required to extrapolate the track parameters and their covariance matrices through the experiment are also implemented as interchangeable modules. Different track parameterizations and extrapolation routines can be used simultaneously for fitting of the same physical track. Representations of detector hits are the third modular ingredient to the framework. The hit dimensionality and orientation of planar tracking detectors are not restricted. Tracking information from detectors which do not measure the passage of particles in a fixed physical detector plane, e.g. drift chambers or TPCs, is used without any simplification. The concept is implemented in a light-weight C++ library called GENFIT, which is available as free software.

  2. Design, construction, and operation of SciFi tracking detector for K2K experiment

    International Nuclear Information System (INIS)

    Suzuki, A.; Park, H.; Aoki, S.; Echigo, S.; Fujii, K.; Hara, T.; Iwashita, T.; Kitamura, M.; Kohama, M.; Kume, G.; Onchi, M.; Otaki, T.; Sato, K.; Takatsuki, M.; Takenaka, K.; Tanaka, Y.; Tashiro, K.; Inagaki, T.; Kato, I.; Mukai, S.; Nakaya, T.; Nishikawa, K.; Sasao, N.; Shima, A.; Yokoyama, H.; Chikamatsu, T.; Hayato, Y.; Ishida, T.; Ishii, T.; Ishino, H.; Jeon, E.J.; Kobayashi, T.; Lee, S.B.; Nakamura, K.; Oyama, Y.; Sakai, A.; Sakuda, M.; Tumakov, V.; Fukuda, S.; Fukuda, Y.; Ishizuka, M.; Itow, Y.; Kajita, T.; Kameda, J.; Kaneyuki, K.; Kobayashi, K.; Kobayashi, Y.; Koshio, Y.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakayama, S.; Obayashi, Y.; Okada, A.; Sakurai, N.; Shiozawa, M.; Suzuki, Y.; Takeuchi, H.; Takeuchi, Y.; Totsuka, Y.; Toshito, T.; Yamada, S.; Miyano, K.; Nakamura, M.; Tamura, N.; Nakano, I.; Yoshida, M.; Kadowaki, T.; Kishi, S.; Yokoyama, H.; Maruyama, T.; Etoh, M.; Nishijima, K.; Bhang, H.C.; Khang, B.H.; Kim, B.J.; Kim, H.I.; Kim, J.H.; Kim, S.B.; So, H.; Yoo, J.H.; Choi, J.H.; Jang, H.I.; Jang, J.S.; Kim, J.Y.; Lim, I.T.; Pac, M.Y.; Kearns, E.; Scholberg, K.; Stone, J.L.; Sulak, L.R.; Walter, C.W.; Casper, D.; Gajewski, W.; Kropp, W.; Mine, S.; Sobel, H.; Vagins, M.; Matsuno, S.; Hill, J.; Jung, C.K.; Martens, K.; Mauger, C.; McGrew, C.; Sharkey, E.; Yanagisawa, C.; Berns, H.; Boyd, S.; Wilkes, J.; Kielczewska, D.; Golebiewska, U.

    2000-01-01

    We describe the construction and performance of a scintillating fiber detector used in the near detector for the K2K (KEK to Kamioka, KEK E362) long baseline neutrino oscillation experiment. The detector uses 3.7 m long and 0.692 mm diameter scintillating fiber coupled to image-intensifier tubes (IIT), and a CCD camera readout system. Fiber sheet production and detector construction began in 1997, and the detector was commissioned in March 1999. Results from the first K2K runs confirm good initial performance: position resolution is estimated to be about 0.8 mm, and track finding efficiency is 98±2% for long tracks (i.e., those which intersect more than 5 fiber planes). The hit efficiency was estimated to be 92±2% using cosmic-ray muons, after noise reduction at the offline stage. The possibility of using the detector for particle identification is also discussed

  3. Performance of a 6x6 segmented germanium detector for {gamma}-ray tracking

    Energy Technology Data Exchange (ETDEWEB)

    Valiente-Dobon, J.J. E-mail: j.valiente-dobon@surrey.ac.uk; Pearson, C.J.; Regan, P.H.; Sellin, P.J.; Gelletly, W.; Morton, E.; Boston, A.; Descovich, M.; Nolan, P.J.; Simpson, J.; Lazarus, I.; Warner, D

    2003-06-01

    A 36 fold segmented germanium coaxial detector has been supplied by EURISYS MESURES. The outer contact is segmented both radially and longitudinally. The signals from the fast preamplifiers have been digitised by 12 bit, 40 MHz ADCs. In this article we report preliminary results obtained using this detector and their relevance for future germanium {gamma}-ray tracking arrays.

  4. Study of uranium mineralization in rock samples from marwat range bannu basin by fission track analysis technique

    International Nuclear Information System (INIS)

    Qureshi, A.Z.; Ullah, K.; Ullah, N.; Akram, M.

    2004-07-01

    The Geophysics Division, Atomic Energy Minerals Centre (AEMC), Lahore has planned a uranium exploration program in Marwat Range, Bannu Basin. In this connection 30 thin sections of rock samples, collected from four areas; namely, Darra Tang, Simukili, Karkanwal and Sheikhillah from Marwat Range, and one from Salt Range were provided to Nuclear Geology Group of Physics Research Division, PINSTECH for the study of nature and mechanism of uranium mineralization These studies are aimed to help in designing uranium exploration strategy by providing the loci of uranium sources in the Marwat and Salt Ranges. The samples have been studied using fission track analysis technique. (author)

  5. Alpha and fission autoradiography of uranium rods

    International Nuclear Information System (INIS)

    Copic, M.; Ilicj, R.; Najzher, M.; Rant, J.

    1977-01-01

    Macro and micro-distribution of uranium minerals in ore bodies are investigated by alpha autoradiography and by neutron induced fission autoradiography using LR 115 solid state track detector. Optimal conditions are determined experimentally for both methods and examples presented. For field applications the alpha autoradiography (author)

  6. A 1024 pad silicon detector to solve tracking ambiguities in high multiplicity events

    International Nuclear Information System (INIS)

    Simone, S.; Catanesi, M.G.; Di Bari, D.; Didonna, V.; Elia, D.; Ghidini, B.; Lenti, V.; Manzari, V.; Nappi, E.

    1996-01-01

    Silicon detectors with two-dimensional pad readout have been designed and constructed for the WA97 experiment at CERN, in order to solve ambiguities for track reconstruction in a silicon microstrip telescope. A high density fanouts has been developed on a glass support to allow the electrical contacts between the detector and the front end electronics. Silicon pad detectors have been successfully operated both during the proton-Pb and Pb-Pb runs of the WA97 experiment. (orig.)

  7. Test beam performance of a tracking TRD [Transition Radiation Detector] prototype

    International Nuclear Information System (INIS)

    Shank, J.T.; Whitaker, J.S.; Polychronakos, V.A.; Radeka, V.; Stephani, D.; Beker, H.; Bock, R.K.; Botlo, M.; Fabjan, C.W.; Pfennig, J.; Price, M.J.; Willis, W.J.; Akesson, T.; Chernyatin, V.; Dolgoshein, B.; Nevsky, P.; Potekhin, M.; Romanjuk, A.; Sosnovtsev, V.; Gavrilenko, I.; Muravjev, S.; Shmeleva, A.

    1990-01-01

    A Tracking Transition Radiation Detector prototype has been constructed and tested. It consists of 240 straw tubes, 4 mm in diameter, imbedded in a polyethylene block acting as the radiator. Its performance as an electron identifier as well as a tracking device for minimum ionizing particles has been determined. 2 refs., 6 figs

  8. Observations on the geometries of etched fission and alpha-recoil tracks with reference to models of track revelation in minerals

    International Nuclear Information System (INIS)

    Jonckheere, R.; Enkelmann, E.; Stuebner, K.

    2005-01-01

    The kinetic and atomistic theories of crystal growth and dissolution are used to interpret the shapes and orientations of fission-track, recoil-track and dislocation etch pits in tri-octahedral phlogopite and di-octahedral muscovite. An atomistic approach combined with symmetry considerations lead to the identification of the periodic bond chains that determine the etch pit morphologies and relative etch rates at a chemical level: O-Mg-O in phlogopite, O-Mg-O-Fe in biotite and O-Al-O in muscovite. Using first-order estimates of the bond strengths, it is possible to account for the relative track etch rates in these minerals. The reported, sometimes simultaneous, occurrence of triangular, polygonal and hexagonal etch pit contours in phlogopite, some of which violate the crystal symmetry, suggests that the cohesion of the phlogopite lattice is lost over a much larger radius than that of the track core around the trajectories of particles for which the energy loss exceeds a threshold value. This is interpreted as an indication of pronounced sublattice and anisotropic effects during track registration

  9. A Novel Generic Framework for Track Fitting in Complex Detector Systems

    OpenAIRE

    Höppner, C.; Neubert, S.; Ketzer, B.; Paul, S.

    2009-01-01

    This paper presents a novel framework for track fitting which is usable in a wide range of experiments, independent of the specific event topology, detector setup, or magnetic field arrangement. This goal is achieved through a completely modular design. Fitting algorithms are implemented as interchangeable modules. At present, the framework contains a validated Kalman filter. Track parameterizations and the routines required to extrapolate the track parameters and their covariance matrices th...

  10. Muon-track studies in a water Cherenkov detector

    Energy Technology Data Exchange (ETDEWEB)

    Etchegoyen, A. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina)]. E-mail: etchegoy@tandar.cnea.gov.ar; Bauleo, P. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Bertou, X. [Enrico Fermfi Institute, University of Chicago, 5640 S. Ellis, Chicago, IL 60637 (United States); Bonifazi, C.B. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Filevich, A. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Medina, M.C. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Melo, D.G. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Rovero, A.C. [Instituto de Astronomia y Fisica del Espacio, CC 67, Suc. 28 (1428) Buenos Aires (Argentina); Supanitsky, A.D. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina); Tamashiro, A. [Departamento de Fisica, Comision Nacional de Energia Atomica, Avenida del Libertador 8250 (1429) Buenos Aires (Argentina)

    2005-06-21

    Background muons may be used in cosmic ray experiments to understand the response of a given detector system and to lay the basis for the further theoretical and simulation work needed in the analysis of air showers. Experiments were performed using a water Cherenkov detector at the Tandar Laboratory. Monte Carlo and semi-analytical calculations were compared to the data.

  11. Precision tracking with a single gaseous pixel detector

    NARCIS (Netherlands)

    Tsigaridas, S.; van Bakel, N.; Bilevych, Y.; Gromov, V.; Hartjes, F.; Hessey, N.P.; de Jong, P.; Kluit, R.

    2015-01-01

    The importance of micro-pattern gaseous detectors has grown over the past few years after successful usage in a large number of applications in physics experiments and medicine. We develop gaseous pixel detectors using micromegas-based amplification structures on top of CMOS pixel readout chips.

  12. CATS: a cellular automaton for tracking in silicon for the HERA-B vertex detector

    International Nuclear Information System (INIS)

    Abt, I.; Emeliyanov, D.; Kisel, I.; Masciocchi, S.

    2002-01-01

    The new track reconstruction program CATS developed for the Vertex Detector System of the HERA-B experiment at DESY is presented. It employs a cellular automaton for track searching and the Kalman filter for track fitting. This results in a very fast algorithm that combines highly efficient track recognition with accurate and reliable track parameter estimation. To reduce the computational cost of the fit an optimized numerical implementation of the Kalman filter is used. Alternative approaches to the track reconstruction in the VDS are also discussed. Since 1999, after extensive tests on simulated data, CATS has been employed to reconstruct experimental data collected in HERA-B. Results regarding tracking performance, the accuracy of track parameter estimates and CPU time consumption are presented

  13. Solid state nuclear track detectors kit for the use in teaching

    International Nuclear Information System (INIS)

    Khouri, M.T.F.C.; Koskinas, M.F.

    1988-11-01

    The kit intends to improve the possibilities in performing experiments of Nuclear Physics in Modern Physics laboratories of Physics Course introducing the solid state nuclear track detectors. In these materials the passage of heavily ionizing nuclear particles creates paths (tracks) that may be revealed and made visible in an optical microscope. By the help of the kit several experiments and/or demonstrations may be performed. The kit contains solid state nuclear track detectors unirradiated and irradiated, irradiated etched and unetched sheets: an alpha source of 241 Am and an instrution text with photomicrographs. To use the kit the laboratory must have an ordinary optical microscope. (author) [pt

  14. Studding the phenomenon of pair production of tracks on plastic detectors during radon measurements

    International Nuclear Information System (INIS)

    Shweikani, R.; Jourbi, B.

    2011-06-01

    Previous studies showed the appearance of many pairs of alpha tracks on the surface of the solid state nuclear track detectors (CR39) when exposed to radon. So the aim of this study was to judge whether this is a statistical or a physical phenomenon. Therefore, a theoretical function representing the probability of forming pairs of tracks on the detector was developed. A statistical studying was done for two sets of (1) mm thickness of CR39 detectors, the first set was exposed in the radon calibration chamber (RCC) with stable radon concentration (170 kBq/m 3 ) for different detectors positions inside and outside the exposure chamber (EC). While the second set was exposed to 241 Am source (1667 Bq) for different exposure times. The results show that the concentration of the single tracks on the detectors in case of covered EC was lower than the same situation without cover. In addition, the concentrations of the single tracks in various exposure situations inside and outside the EC were associated to the effective volumes that each detector sees. Finally, no considerable deference was found between pairs concentration in the two exposure cases (Radon chamber and 241 Am source), and both were lower than the theoretical values which calculated using the theoretical function. This means that pairs formation phenomena is a statistical phenomenon and there is no physical parameters related to radon gas or its daughter's behavior. (author)

  15. Gamma-ray tracking: Characterisation of the AGATA symmetric prototype detectors

    International Nuclear Information System (INIS)

    Boston, A.J.; Boston, H.C.; Cresswell, J.R.; Dimmock, M.R.; Nelson, L.; Nolan, P.J.; Rigby, S.; Lazarus, I.; Simpson, J.; Medina, P.; Santos, C.; Parisel, C.

    2007-01-01

    Each major technical advance in gamma-ray detection devices has resulted in significant new insights into the structure of atomic nuclei. The next major step in gamma-ray spectroscopy involves achieving the goal of a 4pi ball of Germanium detectors by using the technique of gamma-ray energy tracking in electrically segmented Germanium crystals. The resulting spectrometer will have an unparalleled level of detection power for nuclear electromagnetic radiation. Collaborations have been established in Europe (AGATA) [J. Simpson, Acta Phys. Pol. B 36 (2005) 1383. ] and the USA (GRETA/GRETINA) to build gamma-ray tracking spectrometers. This paper discusses the performance of the AGATA (Advanced Gamma Tracking Array) symmetric prototype detectors that have been tested at University of Liverpool. The use of a fully digital data acquisition system has allowed detector charge pulse shapes from a selection of well defined photon interaction positions to be analysed, yielding important information on the position sensitivity of the detector

  16. Gamma-ray tracking: Characterisation of the AGATA symmetric prototype detectors

    Energy Technology Data Exchange (ETDEWEB)

    Boston, A.J. [Oliver Lodge Laboratory, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom)]. E-mail: ajboston@liv.ac.uk; Boston, H.C. [Oliver Lodge Laboratory, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Cresswell, J.R. [Oliver Lodge Laboratory, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Dimmock, M.R. [Oliver Lodge Laboratory, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Nelson, L. [Oliver Lodge Laboratory, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Nolan, P.J. [Oliver Lodge Laboratory, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Rigby, S. [Oliver Lodge Laboratory, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Lazarus, I. [STFC Daresbury Laboratory, Daresbury, Warrington WA4 4AD (United Kingdom); Simpson, J. [STFC Daresbury Laboratory, Daresbury, Warrington WA4 4AD (United Kingdom); Medina, P. [Institut de Recherches Subatomiques, Strasbourg BP28 67037 (France); Santos, C. [Institut de Recherches Subatomiques, Strasbourg BP28 67037 (France); Parisel, C. [Institut de Recherches Subatomiques, Strasbourg BP28 67037 (France)

    2007-08-15

    Each major technical advance in gamma-ray detection devices has resulted in significant new insights into the structure of atomic nuclei. The next major step in gamma-ray spectroscopy involves achieving the goal of a 4pi ball of Germanium detectors by using the technique of gamma-ray energy tracking in electrically segmented Germanium crystals. The resulting spectrometer will have an unparalleled level of detection power for nuclear electromagnetic radiation. Collaborations have been established in Europe (AGATA) [J. Simpson, Acta Phys. Pol. B 36 (2005) 1383. ] and the USA (GRETA/GRETINA) to build gamma-ray tracking spectrometers. This paper discusses the performance of the AGATA (Advanced Gamma Tracking Array) symmetric prototype detectors that have been tested at University of Liverpool. The use of a fully digital data acquisition system has allowed detector charge pulse shapes from a selection of well defined photon interaction positions to be analysed, yielding important information on the position sensitivity of the detector.

  17. Comparison of Thermal Neutron Flux Measured by Uranium 235 Fission Chamber and Rhodium Self-Powered Neutron Detector in MTR

    International Nuclear Information System (INIS)

    Fourmentel, D.; Filliatre, P.; Barbot, L.; Villard, J.-F.; Lyoussi, A.; Geslot, B.; Malo, J.-Y.; Carcreff, H.; Reynard-Carette, C.

    2013-06-01

    Thermal neutron flux is one of the most important nuclear parameter to be measured on-line in Material Testing Reactors (MTRs). In particular two types of sensors with different physical operating principles are commonly used: self-powered neutron detectors (SPND) and fission chambers with uranium 235 coating. This work aims to compare on one hand the thermal neutron flux evaluation given by these two types of sensors and on the other hand to compare these evaluations with activation dosimeter measurements, which are considered as the reference for absolute neutron flux assessment. This study was conducted in an irradiation experiment, called CARMEN-1, performed during 2012 in OSIRIS reactor (CEA Saclay - France). The CARMEN-1 experiment aims to improve the neutron and photon flux and nuclear heating measurements in MTRs. In this paper we focus on the thermal neutron flux measurements performed in CARMEN-1 experiment. The use of fission chambers to measure the absolute thermal neutron flux in MTRs is not very usual. An innovative calibration method for fission chambers operated in Campbell mode has been developed at the CEA Cadarache (France) and tested for the first time in the CARMEN-1 experiment. The results of these measurements are discussed, with the objective to measure with the best accuracy the thermal neutron flux in the future Jules Horowitz Reactor. (authors)

  18. LHCb: Alignment of the LHCb Detector with Kalman Filter Fitted Tracks

    CERN Multimedia

    Amoraal, J; Hulsbergen, W; Needham, M; Nicolas, L; Pozzi, S; Raven, G; Vecchi, S

    2009-01-01

    We report on an implementation of a global chisquare algorithm for the simultaneous alignment of all tracking systems in the LHCb detector. Our algorithm uses hit residuals from the standard LHCb track fit which is based on a Kalman filter. The algorithm is implemented in the LHCb reconstruction framework and exploits the fact that all sensitive detector elements have the same geometry interface. A vertex constraint is implemented by fitting tracks to a common point and propagating the change in track parameters to the hit residuals. To remove unconstrained or poorly constrained degrees of freedom (so-called weak modes) the average movements of (subsets of) alignable detector elements can be fixed with Lagrange constraints. Alternatively, weak modes can be removed with a cutoff in the eigenvalue spectrum of the second derivative of the chisquare. As for all LHCb reconstruction and analysis software the configuration of the algorithm is done in python and gives detailed control over the selection of alignable ...

  19. Tracking in Dense Environments for the HL-LHC ATLAS Detector

    CERN Document Server

    Cormier, Felix; The ATLAS collaboration

    2018-01-01

    Tracking in dense environments, such as in the cores of high-energy jets, will be key for new physics searches as well as measurements of the Standard Model at the High Luminosity LHC (HL-LHC). The HL-LHC will operate in challenging conditions with large radiation doses and high pile-up (up to $\\mu=200$). The current tracking detector will be replaced with a new all-silicon Inner Tracker for the Phase II upgrade of the ATLAS detector. In this talk, characterization of the HL-LHC tracker performance for collimated, high-density charged particles arising from high-momentum decays is presented. In such decays the charged-particle separations are of the order of the tracking detector granularity, leading to challenging reconstruction. The ability of the HL-LHC ATLAS tracker to reconstruct the tracks in such dense environments is discussed and compared to ATLAS Run-2 performance for a variety of relevant physics processes.

  20. Thermal neutron detection by means of an organic solid-state track detector

    International Nuclear Information System (INIS)

    Doerschel, B.; Streubel, G.

    1979-01-01

    Thermal neutrons can be detected by means of organic solid-state track detectors if they are combined with radiators in which charged secondary particles are produced in neutron interaction processes. The secondary particles can produce etchable tracks in the detector material. For thermal neutron fluence determination from the track densities, the thermal neutron sensitivity was calculated for cellulose triacetate detectors with LiF radiators, taking into account energy and angular distribution of the alpha particles produced in the LiF radiator. This value is in good agreement with the sensitivity measured during irradiation in different neutron fields if corrections are considered the production of etchable or visuable tracks. Measuring range and measuring accuracy meet the requirements of thermal neutron detection in personnel dosimetry. Possibilities of extending the measuring range are discussed. (author)

  1. Fission products collecting devices

    International Nuclear Information System (INIS)

    Matsumoto, Hiroshi

    1979-01-01

    Purpose: To enable fission products trap with no contamination to coolants and cover gas by the provision of a fission products trap above the upper part of a nuclear power plant. Constitution: Upon fuel failures in a reactor core, nuclear fission products leak into coolants and move along the flow of the coolants to the coolants above the reactor core. The fission products are collected in a trap container and guided along a pipeline into fission products detector. The fission products detector monitors the concentration of the fission products and opens the downstream valve of the detector when a predetermined concentration of the fission products is detected to introduce the fission products into a waste gas processing device and release them through the exhaust pipe. (Seki, T.)

  2. Development of cryogenic tracking detectors for very high luminosity experiments

    CERN Document Server

    Härkönen, J; Anbinderis, T; Bates, R; de Boer, W; Borchi, E; Bruzzi, M; Buttar, C; Chen, W; Cindro, V; Czellar, S; Eremin, V; Furgeri, A; Gaubas, E; Heijne, E; Ilyashenko, I; Kalesinskas, V; Krause, M; Li, Z; Luukka, P; Mandic, I; Menichelli, D; Mikuz, M; Militaru, O; Mueller, S; Niinikoski, T O; O’Shea, V; Parkes, C; Piotrzkowski, K; Pirollo, S; Pusa, P; Räisänen, J; Rouby, X; Tuominen, E; Tuovinen, E; Vaitkus, J; Verbitskaya, E; Väyrynen, S; Zavrtanik, M

    2009-01-01

    Experimental results and simulations of Charge Collection Efficiency (CCE) of Current Injected Detectors (CIDs) are focused. CID is a concept where the current is limited by the space charge. The injected carriers will be trapped by the deep levels. This induces a stable electric field through the entire bulk regardless of the irradiation fluence the detector has been exposed. Our results show that the CCE of CIDs is about two times higher than of regular detectors when irradiated up to 1×1016 cm−2. The higher CCE is achieved already at −50 °C temperatures.

  3. New fission-track ages of mio-pliocene tuffs in the Sierras Pampeanas and Precordillera of Argentina

    International Nuclear Information System (INIS)

    Tabbutt, K.; Naeser, C.W.; Jordan, T.E.; Cerveny, P.F.

    1989-01-01

    Fission-track dates were determined for 18 volcanic tuff horizons located in nine Neogene foreland basin sequences distributed throughout the Precordillera and Sierras Pampeanas of Northwestern Argentina, an area of nearly horizontal subduction. These and other data indicate that a lower age limit for the sedimentary sequences studied is approximately 17 Ma. Therefore these fission-track dates constrain both the history of volcanic activity and the time of deposition in several foreland basins from the middle Miocene to Recent. Although the dates range from 3.6±0.8 Ma to 17.0±1.9 Ma, there is a marked increase in the number of ashes younger than 9 Ma. This implies that two distinct episodes of volcanic activity affected the region. The source of some of these tuffs is unknown but they are probably limited to the 'flat-slab' region between 27 deg and 32 deg S. Tuffs at Rio Blanco and Santa Florentina that are spatially associated with the Mogotes dacite domes of the Famatina Range represented magmatism bracketed from about 7 to 4 Ma in the region underlain by the flat-subducted plate. The stratigraphic relations in the basins show that the faulting that uplifted Sierra de Famatina was contemporaneous with the volcanism which reached the surface along the bounding faults. (Author) [es

  4. Multiple cooling episodes in the Central Tarim (Northwest China) revealed by apatite fission track analysis and vitrinite reflectance data

    Science.gov (United States)

    Chang, Jian; Qiu, Nansheng; Song, Xinying; Li, Huili

    2016-06-01

    Apatite fission track and vitrinite reflectance are integrated for the first time to study the cooling history in the Central Tarim, northwest China. The paleo-temperature profiles from vitrinite reflectance data of the Z1 and Z11 wells showed a linear relationship with depth, suggesting an approximately 24.8 °C/km paleo-geothermal gradient and 2700-3900 m of erosion during the Early Mesozoic. The measured apatite fission track ages from well Z2 in the Central Tarim range from 39 to 159 Ma and effectively record the Meso-Cenozoic cooling events that occurred in Central Tarim. Moreover, two cooling events at 190-140 Ma in the Early Jurassic-Early Cretaceous and 80-45 Ma in the Late Cretaceous-Paleocene revealed by measured AFT data and thermal modeling results are related to the collisions of the Qiangtang-Lhasa terranes and the Greater India Plate with the southern margin of the Eurasian Plate, respectively. This study provides new insights into the tectonic evolution of the Tarim Basin (and more broadly Central Asia) and for hydrocarbon generation and exploration in the Central Tarim.

  5. Thermal and exhumation history of Sakhalin Island (Russia) constrained by apatite U-Pb and fission track thermochronology

    Science.gov (United States)

    Glorie, Stijn; Alexandrov, Igor; Nixon, Angus; Jepson, Gilby; Gillespie, Jack; Jahn, Bor-Ming

    2017-08-01

    Sakhalin Island represents a key locality to study the tectonic evolution of the western Pacific. The island is located at the Amur-Okhotsk plate margin and records a complex thermotectonic history. Apatite double dating (U-Pb and fission track) and thermal history modelling were applied to three late Eocene granitoid massifs within central and southern Sakhalin: the Aniva, Okhotsk and Langeri complexes. Apatite U-Pb results yield consistent late Eocene (∼40-37 Ma) ages, suggesting rapid post-magmatic cooling. Apatite fission track results reveal bimodal age distributions with late Eocene - early Oligocene (∼38-33 Ma) and early Miocene (∼20-17 Ma) age populations that can be correlated with variations in Uranium and Chlorine concentrations. Thermal history modelling translates the AFT age bimodality into two-phase cooling histories. The timing of the early cooling phase (∼38-33 Ma) corresponds with the apatite U-Pb ages, indicating rapid cooling to at least ∼100 °C during the late Oligocene. The second cooling phase at ∼20-17 Ma cooled the samples to near-surface temperatures. Both cooling phases correspond with regional unconformities and subsequent accelerations in sedimentation rate, suggesting that cooling was a response to rapid exhumation. In addition, our data suggests that the studied terranes record differential exhumation with respect to the structural architecture. The Miocene exhumation pulse is coeval with the timing of transpressional fault displacement and the subsequent opening of the Kuril Basin.

  6. Development of a new approach to simulate a particle track under electrochemical etching in polymeric detectors

    International Nuclear Information System (INIS)

    Mostofizadeh, Ali; Huang, Yudong; Kardan, M. Reza; Babakhani, Asad; Sun Xiudong

    2012-01-01

    A numerical approach based on image processing was developed to simulate a particle track in a typical polymeric detector, e.g., polycarbonate, under electrochemical etching. The physical parameters such as applied voltage, detector thickness, track length, the radii of curvature at the tip of track, and the incidence angle of the particle were considered, and then the boundary condition of the problem was defined. A numerical method was developed to solve Laplace equation, and then the distribution of the applied voltage was obtained through the polymer volume. Subsequently, the electric field strengths in the detector elements were computed. In each step of the computation, an image processing technique was applied to convert the computed values to grayscale images. The results showed that a numerical solution to Laplace equation is dedicatedly an attractive approach to provide us the accurate values of electric field strength through the polymeric detector volume as well as the track area. According to the results, for a particular condition of the detector thickness equal to 445 μm, track length of 21 μm, the radii of 2.5 μm at track tip, the incidence angle of 90°, and the applied voltage of 2080 V, after computing Laplace equation for an extremely high population of 4000 × 4000 elements of detector, the average field strength at the tip of track was computed equal to 0.31 MV cm −1 which is in the range of dielectric strength for polymers. The results by our computation confirm Smythe’s model for estimating the ECE-tracks.

  7. The former tests realized to a personal neutron dosemeter based on solid nuclear tracks detector

    International Nuclear Information System (INIS)

    Camacho, M.E.; Tavera, L.; Balcazar, M.

    1997-01-01

    Due to the increase in the use of neutron radiation a personal neutron dosemeter based on solid nuclear tracks detector (DSTN) was designed and constructed. The personal dosemeter design consists of three arrangements. The first one consists of a plastic nuclear tracks detector (LR115 or CR39) in contact with a LiF pellet. The second one is the same that above but it placed among two cadmium pellets and, the third one is formed by the alone detector without converter neither neutron absorber. The three arrangements are placed inside a plastic porta detector hermetically closed to avoid the bottom produced by environmental radon whichever both detectors (LR115 and CR39) are sensitive. In this work the former tests realized to that dosemeter are presented. (Author)

  8. Determination of trace U in beverages and mineral water using SSNTD (solid state nuclear track detector)

    International Nuclear Information System (INIS)

    Lin Junying; Zheng Liping; Cheng Yulin; Hao Xiuhong

    1991-01-01

    Trace U in beverages and mineral water has been estimated using the fission track analysis technique. The U contents in beverages vary from 0.26 ± 0.03 to 1.65 ± 0.07 ppb, with an average of 0.93 ± 0.05 ppb. The mean U content in mineral water is 9.20 ± 0.16 ppb, which is 10 times higher than that in other beverages

  9. Personal neutron dosimeter using solid-state track detector

    International Nuclear Information System (INIS)

    Mettripan, S.

    1980-01-01

    A cellulose nitrate film coated on both sides with lithium tetraborate was used as a neutron dosimeter for surveillance of personnel exposed to thermal and epithermal neutron. It was found that the optimum etching conditions used were 10% solution of sodium hydroxide, 60 degrees C and 20 minutes etching time and the alpha track densities from the (n,α) reaction on the films were proportional to thermal and epithermal neutron fluxes. The response of the film was found to be 1.068 x 10 -3 tracks per thermal neutron and 3.438 x 10 -4 tracks per epithermal neutron

  10. Fast track trigger processor for the OPAL detector at LEP

    Energy Technology Data Exchange (ETDEWEB)

    Carter, A A; Carter, J R; Ward, D R; Heuer, R D; Jaroslawski, S; Wagner, A

    1986-09-20

    A fast hardware track trigger processor being built for the OPAL experiment is described. The processor will analyse data from the central drift chambers of OPAL to determine whether any tracks come from the interaction region, and thereby eliminate background events. The processor will find tracks over a large angular range, vertical strokecos thetavertical stroke < or approx. 0.95. The design of the processor is described, together with a brief account of its hardware implementation for OPAL. The results of feasibility studies are also presented.

  11. Fast neutron dosimetry by means of different solid state nuclear track detectors

    International Nuclear Information System (INIS)

    Spurny, F.; Turek, K.

    1977-01-01

    The comparative study of three different types of fast neutron dosimeters based on solid state nuclear track detectors is presented; the dosimeters studied were: - microscopic soda glass in contact with 232 Th; - polycarbonate Makrofol E; and - cellulose nitrate Kodak LR 115. All detectors were evaluated by visual counting in a microscope. The authors have studied such properties as the background, angular as well as energetical dependences of detectors. The results obtained show that all studied detectors are suitable for fast neutron dosimetry; their application depends however on the concrete experimental conditions (neutron spectrum, fluence etc.). Both advantages and disadvantages of each of them are presented. (Auth.)

  12. Fast track-finding trigger processor for the SLAC/LBL Mark II Detector

    International Nuclear Information System (INIS)

    Brafman, H.; Breidenbach, M.; Hettel, R.; Himel, T.; Horelick, D.

    1977-10-01

    The SLAC/LBL Mark II Magnetic Detector consists of various particle detectors arranged in cylindrical symmetry located in and around an axial magnetic field. A versatile, programmable secondary trigger processor was designed and built to find curved tracks in the detector. The system operates at a 10 MHz clock rate with a total processing time of 34 μsec and is used to ''trigger'' the data processing computer, thereby rejecting background and greatly improving the data acquisition aspects of the detector-computer combination

  13. Vacuum effect on the etch induction time and registration sensitivity of polymer track detectors

    International Nuclear Information System (INIS)

    Csige, I.; Hunyadi, I.; Somogyi, G.

    1988-01-01

    The effect of a vacuum on etch induction time and track etch rate ratio of some polymer track detectors was studied systematically with alpha particles of different energies. It was found that the etch induction time increases, and the track etch rate ratio decreases, drastically when the detectors were irradiated in a vacuum and also kept in a vacuum for a few hours before and for a few minutes after the irradiation. These times proved to be characteristic for the outgassing of oxygen from the sheets and the stabilization of latent tracks, respectively. The role of oxygen in latent track formation is discussed. We have found that the vacuum effect is most significant near the surface. Its diminution with depth depends on the time of outgassing in accordance with the time variation of the dissolved oxygen concentration profile inside the sheets. (author)

  14. Vacuum effect on the etch induction time and registration sensitivity of polymer track detectors

    Energy Technology Data Exchange (ETDEWEB)

    Csige, I.; Hunyadi, I.; Somogyi, G. (Magyar Tudomanyos Akademia, Debrecen (Hungary). Atommag Kutato Intezete); Fujii, M. (Institute of Space and Astronautical Science, Sagamihara (Japan))

    1988-01-01

    The effect of a vacuum on etch induction time and track etch rate ratio of some polymer track detectors was studied systematically with alpha particles of different energies. It was found that the etch induction time increases, and the track etch rate ratio decreases, drastically when the detectors were irradiated in a vacuum and also kept in a vacuum for a few hours before and for a few minutes after the irradiation. These times proved to be characteristic for the outgassing of oxygen from the sheets and the stabilization of latent tracks, respectively. The role of oxygen in latent track formation is discussed. We have found that the vacuum effect is most significant near the surface. Its diminution with depth depends on the time of outgassing in accordance with the time variation of the dissolved oxygen concentration profile inside the sheets. (author).

  15. The potential of apatite fission track dating of vertical profiles in Namibia and the implications for passive margin evolution

    International Nuclear Information System (INIS)

    Raab, M.J.; Brown, R.W.; Cockburn, H.A.P.

    1999-01-01

    Full text: The on- and offshore geology of the Namibian passive continental margin has experienced kilometer scale erosion since South Atlantic opening in Lower Cretaceous times. A vertical apatite fission track profile of four samples in the Namibian highland has been analysed to constrain the low temperature thermal history of that area since the Pan-African Damara Orogeny at about 550 Ma. As a temperature sensitive thermochronological technique apatite fission track analysis is a powerful tool in constraining the low temperature history of rocks over a range of 60-110 deg C. These temperatures, depending on the geothermal gradient, equal a burial depth of 3-5 km so the method can reconstruct the cooling history of rocks as they approached the surface in response to erosion and tectonic processes. The four apparent apatite cooling ages are taken over a vertical distance of 300 m from the Windhoek Graben 40 km north of Windhoek. Forward modelling of the age and track length distribution has shown that these samples experienced high palaeotemperatures from ca. 90 to 95 deg C in the Late Cretaceous. This information was used to calculate the palaeogeothermal gradient at that time (20 deg C/km) which gives an estimate of the sedimentary cover of about 4.5 km which has been removed over a few million years in the Late Cretaceous. It was previously thought that the Namibian highland has been exposed at the surface more or less since the Permo-Carboniferous. In fact the samples provide evidence for a post Carboniferous reburial history of several kilometers followed by a short period of accelerated denudation in the Late Cretaceous at about 70 Ma. This might imply a far larger extent of the Etendeka flood basalts (132 Ma) and/or an underestimated sedimentary Karoo (Permian to Jurassic) thickness. The wider importance of these four data is that they detect the geomorphic impact of a global change of plate motion along the passive margin of Namibia which is known from a

  16. A ''quick DYECET'' method for ECE particle tracks in polymer detectors

    International Nuclear Information System (INIS)

    Sohrabi, M.; Mahdi, S.

    1993-01-01

    The new dyed electrochemically etched track (DEYCET) method recently developed at the National Radiation Protection Department (NRPD) of the Atomic Energy Organization of Iran (AEOI) using sensitization and dyeing steps is a useful and powerful method for dyeing charged particle and neutron-induced-recoil tracks in polymer detectors. This original DYECET method is effective but time consuming due to the steps for sensitization and dyeing which usually takes several hours. A ''Quick DYECET'' method, also recently developed in our laboratory, is introduced in this paper which dyes ECE tracks effectively in different colours within a few minutes. This new method can dye ECE tracks, cracks, fractures and fractals with different water and/or alcohol soluble dyes using cold or hot dyebaths. The method provides a high contrast and a high resolution of ECE tracks for visual track counting especially at high track densities. Some preliminary results are reported and discussed. (author)

  17. Development and simulation of a Ge/Si multi-detector spectrometer for fission products traces detection in the environment

    International Nuclear Information System (INIS)

    Cagniant, Antoine

    2015-01-01

    For the verification of the Comprehensive nuclear Test Ban Treaty (CTBT), the measurement of fission products trace levels in the environment is fundamental. Such measurement is a key indicator of a nuclear explosion. For constant amelioration of these measurements, the CEA/DAM-Ile de France has developed and installed a new dedicated surface spectrometer. Named GAMMA3, it is equipped with three germanium detectors, two silicon detectors (integrated in a dedicated gas cell, the PIPSBox) and includes an optimized shielding.This shielding reduces greatly the interference of environmental photons, muons and neutrons with the detectors. The residual radiological background measured inside the shielding is the community's lowest for a surface laboratory. This set of high energy resolution detectors allows the operator to optimize a measurement according to the sample geometry, activity or nature. More precisely, a radioactive noble gas can be measured by photon/electron coincidence, an active sample can be measured by photon/photon coincidence, and a low-active sample can be measured in a high-efficiency configuration. Combining optimized shielding and optimized measurement, Minimum Detectable Activities required for CTBT certification are obtained quickly. Specifically, MDA is reached in 5 hours for 140-Ba (24 mBq), in 6h30 hours for 131m/133m-Xe (5 mBq) and in 7h15 for 133-Xe (5 mBq), when CTBT requirement is in 6 days. (author) [fr

  18. Determining of the track parameters in solid state nuclear track detectors Cr 39 due to alpha particles

    International Nuclear Information System (INIS)

    Kostic, D.; Nikezic, D.

    1997-01-01

    An equation of the etch pit wall is proposed to be used for simulation of the track growth and calculating the major and the minor axis of etch pit opening. Dependence on the following parameters is set up: distance along a track from the point where the particle entered the detector, ratio of the track etch wall to the bulk etch rate, integration constant determined from particle penetration depth and normal distance from the particle trajectory to the etch pit wall. The corresponding computer program was written. The input parameters of this program are: alpha particles energy, incidence angle and removed layer; the output gives track parameters. The results obtained by this method are compared to another approach given by Somogy and Szalay (1973) and a reasonably good agreement is found. (author)

  19. Use of cellulose nitrate plastic track detectors in neutron personnel monitoring

    International Nuclear Information System (INIS)

    Venkataraman, G.; Marathe, P.K.; Joshi, R.V.

    1975-01-01

    Cellulose nitrate, which is a sensitive plastic material wherein even proton tracks could be recorded, was studied with a view to using it for personnel neutron monitoring work. It was found that among the commercially available plastics, the colourless transparent Daicel 6000 variety having a thickness of 0.6mm is satisfactory form the point of view of track recognition. The material was exposed to thermal neutrons, fission neutrons, neutrons from an Am-Be source and to 14 MeV neutrons. As is to be expected, there is no thermal neutron sensitivity. The sensitivity to fast neutrons is less by a factor of two as compared to that of the NTA nuclear track emulsion. It was observed that the background tracks found in the plastic correspond to nearly 100 mrem of fast neutron dose equivalent. It is felt that at present cellulose nitrate is useful for monitoring personnel involved in nuclear criticality accidents. (author)

  20. Tracking and b-tagging with pixel vertex detector in ATLAS experiment at LHC

    International Nuclear Information System (INIS)

    Vacavant, L.

    1997-06-01

    The capability of the ATLAS detector to tag b-jets is studied, using the impact parameter of charged tracks. High b-tagging performance is needed at LHC, especially during the first years of running, in order to see evidence of the Higgs boson if its mass lies between 80 and 120 GeV/c 2 . A pattern-recognition algorithm has been developed for this purpose, using a detailed simulation of the ATLAS inner detector. Track-finding starts from the pixel detector layers. A 'hyper-plane' concept allows the use of a simple tracking algorithm though the complex geometry. High track-finding efficiency and reconstruction quality ensure the discrimination of b-jets from other kinds of jets. After full simulation and reconstruction of H → bb-bar, H → gg, H → uu-bar, H → ss-bar and H → cc-bar events (m H = 100 GeV/c 2 ), the mean rejections achieved against non-b-jets for a 50% b-jet tagging efficiency are as follows: R g =39±5 R u = 60 ± 9 R s = 38 ± 5 R c = 9 ± 1 The analysis of data from the first radiation-hard pixel detector prototypes justifies the potential of these detectors for track-finding and high-precision impact parameter measurement at LHC. (author)

  1. Automatic methods for processing track-detector data at the PAVICOM facility

    International Nuclear Information System (INIS)

    Aleksandrov, A.B.; Goncharova, L.A.; Polukhina, N.G.; Fejnberg, E.L.; Davydov, D.A.; Publichenko, P.A.; Roganova, T.M.

    2007-01-01

    New automatic methods essentially simplify and hasten the data treatment of tracking detectors. It allows handling big data files and appreciably improves their statistics; this fact predetermines an elaboration of new experiments, which suppose to use large volume targets, emulsive and solid-state large square tracking detectors. Thereupon the problem of training competent physicists able to work on modern automatic equipment is very relevant. About ten Moscow students working in LPI at PAVICOM facility master new methods every year. Most of the students working in high-energy physics take the print only about archaic hand methods of data handling from tracking detectors. In 2005 on the base of the PAVICOM facility and physics training of the MSU a new educational work for determination of the energy of neutrons passing through nuclear emulsion, which lets students acquire a base habit of data handling from tracking detectors using an automatic facility, was prepared; it can be included in the training process for students of any physical faculty. Specialists mastering methods of an automatic handling by the simple and obvious example of tracking detectors will be able to use their knowledge in various areas of science and techniques. The organization of upper division courses is a new additional aspect of using the PAVICOM facility described in an earlier paper [4

  2. Further development of a track detector as the spectrometer of linear energy transfer

    International Nuclear Information System (INIS)

    Spurny, F.; Bednar, J.; Vlcek, B.; Botollier-Depois, J.F.

    1998-01-01

    Track revealing in a track etch detector is a phenomenon related to the linear energy transfer (LET) of the particle registered. The measurements of track parameters permit to determine the LET corresponding to each revealed track, i.e. LET spectrum. We have recently developed a spectrometer of LET based on the chemically etched polyallyldiglycolcarbonate (PADC). In this contribution the results obtained with such spectrometer in some neutron fields are presented, analyzed and discussed. Several radionuclide neutron sources have been used, LET spectrometer has been also exposed in high energy neutron reference fields at CERN and JINR Dubna, and on board aircraft. (author)

  3. Implementation of the P barANDA Planar-GEM tracking detector in Monte Carlo simulations

    Science.gov (United States)

    Divani Veis, Nazila; Ehret, Andre; Firoozabadi, Mohammad M.; Karabowicz, Radoslaw; Maas, Frank; Saito, Nami; Saito, Takehiko R.; Voss, Bernd; PANDA Gem-Tracker Subgroup

    2018-02-01

    The P barANDA experiment at FAIR will be performed to investigate different aspects of hadron physics using anti-proton beams interacting with a fixed nuclear target. The experimental setup consists of a complex series of detector components covering a large solid angle. A detector with a gaseous active media equipped with gas electron multiplier (GEM) technique will be employed to measure tracks of charged particles at forward direction in order to achieve a high momentum resolution. In this work, a full setup of the GEM tracking detector has been implemented in the P barANDA Monte Carlo simulation package (PandaRoot) based on the current technical and conceptual design, and the expected performance of the P barANDA GEM-tracking detector has been investigated. Furthermore, material-budget studies in terms of the radiation length of the P barANDA GEM-tracking detector have been made in order to investigate the effect of the detector materials and its associated structures to particle measurements.

  4. Determination of Nuclear Track Parameters for LR-115 Detector by Using of MATLAB Software Technique

    International Nuclear Information System (INIS)

    AL-Jomaily, F.M.; AL-joburi, H.A.; Mheemeed, A.K.

    2013-01-01

    The nuclear track detector parameters, such as nuclear track diameter D(μm), number of track N T and area of track A T were determined by using MATLAB software technique for IR-115 detector irradiated by alpha particle from 241 Am source under 1.5, 2.5 and 3.5 MeV at etching time T B of 90, 120, 150 and 180 min.By using the image analysis of MATLAB software for nuclear track, the full width at half maximum FWHM and relative resolution R% were calculated for each energy of alpha particles.In this study, it was shown that increasing the alpha energy on the IR-115 detector leads to increased etching time T B and the dropping of R% to minimum value, and then reach a stable value before dropping at values 1.5, 2.5 MeV and unstable at 3.5 MeV. Imaging analysis by MATLAB technique which used in this study reflect good and accurate results for nuclear track detector parameters and we recommend using this technique for determination of these parameters

  5. Proceedings of the seventeenth national symposium on solid state nuclear track detectors and their applications: abstracts and souvenir

    International Nuclear Information System (INIS)

    Patel, Gaurang; Kishore, Sangeeta; Patel, Purvi

    2011-10-01

    The proceedings of the seventeenth national symposium on solid state nuclear track detectors and their applications (SSNTD-17) contains a number of research papers on different areas of solid state nuclear track detectors. It provides a common scientific platform to the scientists for sharing their knowledge and reviews the present state-of-art and advancements in the field of solid state nuclear track detectors and their applications and also some aspects of nuclear energy. Papers relevant to INIS are indexed separately

  6. Magnetic Field Requirements for a Detector at the Linear Collider Using a TPC as Main Tracking Device

    CERN Document Server

    Klempt, W

    2010-01-01

    This note describes the requirements to the magnetic field which occur in an ILD like detector at ILC or CLIC. In particular we describe requirements introduced by choosing a TPC as main tracking detector.

  7. The effect of the nuclear track detectors' position on the radon concentration measurements

    International Nuclear Information System (INIS)

    Yilmaz, A.; Kuerkcueoglu, M. E.; Haner, B.

    2009-01-01

    It is important to determine the radon concentration values of the underground mines according to workers' health. For this purpose, to be able to measure radon concentrations by using passive nuclear etched track detectors, CR-39 detectors were placed into 66 points on the way of aeration galleries of Armutcuk, Amasra, Karadon, Kozlu and Uezuelmez bituminous coal mines which are known as the Carboniferous outcrops of the Western Black Sea Area in Turkey. In every measurement point, a pair of detectors, one of them is being perpendicular and the other one is parallel to air flow, were exposed to radon gases over 40 days for four seasons of the year 2008. The relationship between the readings of vertically and horizontally positioned detectors was investigated by evaluating the effect of the detectors' positions on the detected radon concentrations. It can be concluded that, the vertically positioned detectors, in general, recorded higher radon gases concentration values than that of the horizontally positioned ones.

  8. Development of the dyed-track method for Kodak CN-85 detector. No. E/3

    International Nuclear Information System (INIS)

    Somogyi, G.; Toth-Szilagyi, M.; Varga, Zs.; Monnin, M.; Lferde, M.

    1983-01-01

    The dyed-track method has been successfully developed for cellulose derivatives. The track parameters (width, coloration deepness, contrast, registration sensitivity), however, proved to be very dependent on the detector material and on the track processing conditions. In the authors' previous works optimum conditions were presented mostly for cellulose acetate sheets. In the present work the influence of track processing parameters on the dyed-track formation was studied in Kodak cellulose nitrate detector called CN-85. It is found that in this material optimum dyed-tracks can be produced with using no swelling but with a thermal annealing at 100 deg C for 1 hour after particles irradiation. For sensitization a treatment with 15% HCL at 22 deg C for 20 hours and for dyeing 0.3 wt% Rhodamine-B at 100 deg C for 1 hour proved to be best. For understanding the track dyeing phenomenon the coloration behaviour of electron-irradiated CN-85 detectors was studied. (author)

  9. Development of the dyed-track method for Kodak CN-85 detector

    International Nuclear Information System (INIS)

    Somogyi, G.; Toth-Szilagyi, M.; Varga, Z.; Monnin, M.; Lferde, M.

    1984-01-01

    The dyed-track method has been successfully developed for cellulose derivatives. The track parameters (width, colouration deepness, contrast, registration sensitivity), however, proved to be very dependent on the detector material and on the track processing conditions. In our previous works optimum conditions were presented mostly for cellulose acetate sheets. In the present work we have studied the influence of track processing parameters on the dyed-track formation in Kodak cellulose nitrate detector called CN-85. It is found that in this material optimum dyed-tracks can be produced with using no swelling but with a thermal annealing at 100 deg C for 1 hour after particle irradiation. For sensitization a treatment with 15% HCl at 22 deg C for 20 hours and for dyeing 0.3 wt% Rhodamine-B at 100 deg C for 1 hour proved to be the best. For better understanding the track dyeing phenomenon we have studied the colouration behaviour of electron-irradiated CN-85 detectors. (author)

  10. Development of the dyed-track method for Kodak CN-85 detector

    Energy Technology Data Exchange (ETDEWEB)

    Somogyi, G.; Toth-Szilagyi, M.; Varga, Z. (Magyar Tudomanyos Akademia, Debrecen. Atommag Kutato Intezete); Monnin, M.; Lferde, M. (Clermont-Ferrand-2 Univ., 63 - Aubiere (France). Lab. de Physique Corpusculaire)

    1984-01-01

    The dyed-track method has been successfully developed for cellulose derivatives. The track parameters (width, colouration deepness, contrast, registration sensitivity), however, proved to be very dependent on the detector material and on the track processing conditions. In our previous works optimum conditions were presented mostly for cellulose acetate sheets. In the present work we have studied the influence of track processing parameters on the dyed-track formation in Kodak cellulose nitrate detector called CN-85. It is found that in this material optimum dyed-tracks can be produced with using no swelling but with a thermal annealing at 100 deg C for 1 hour after particle irradiation. For sensitization a treatment with 15% HCl at 22 deg C for 20 hours and for dyeing 0.3 wt% Rhodamine-B at 100 deg C for 1 hour proved to be the best. For better understanding the track dyeing phenomenon we have studied the colouration behaviour of electron-irradiated CN-85 detectors.

  11. Chrono-thermométrie par traces de fission : une perspective nouvelle pour la prospection pétrolière Chronothermometry by Fission-Track Dating: New Means for Petroleum Prospection

    Directory of Open Access Journals (Sweden)

    Storzer D.

    2006-11-01

    Full Text Available La propriété caractéristique des traces de fission d'enregistrer les paléotempératures offre la possibilité unique de caler des événements thermiques dans leur contexte géologique et donc de modéliser quantitativement les histoires thermiques des roches. Le thermomètre traces de fission-apatite enregistre les paléo-températures dans un intervalle compris entre 30 et 170°C, domaine qui inclut les températures généralement retenues pour la genèse optimale des hydrocarbures liquides. La formation, la maturation et la destruction des hydrocarbures, de la même façon que la guérison des traces latentes, sont fonction des deux paramètres temps et températures; en conséquence, l'étude détaillée de l'effacement progressif des traces latentes fossiles dans les apatites en fonction de leur profondeur dans un puits, conduit à des indications précises sur les variations de la température en fonction du temps à l'intérieur de la fenêtre à huile. Ces deux informations sont obtenues en combinant la datation traces de fission-isochrone et les analyses de longueurs des traces de fission. Le potentiel de la méthode des traces de fission dans son application à la reconstitution de l'histoire thermique des bassins sédimentaires est illustré à partir de l'analyse d'apatites détritiques provenant des bassins intérieur et côtier du Gabon d'une part et du bassin d'Otway en Australie du Sud d'autre part. The characteristic property of fission tracks to record paleotemperatures provides a unique possibility of setting thermal events in their geological context and hence of quantitatively modeling the thermal histories of rocks. The fission track apatite-thermometer records paleotemperatures in the interval between 30 and 170°C, a range that includes the temperatures generally considered to be required for the optimum formation of liquid hydrocarbons. The formation, maturation and destruction of hydrocarbons, as well as the

  12. Performance and track-based alignment of the Phase-1 upgraded CMS pixel detector

    CERN Document Server

    Botta, Valeria

    2017-01-01

    The Compact Muon Solenoid (CMS) detector is a multi-purpose detector constructed in order to study high-energy particle collisions at the Large Hadron Collider (LHC) at CERN. The all-silicon design of the tracking system of the CMS experiment provided excellent resolution for charged tracks and an efficient tagging of jets during Run 1 and Run 2 of the LHC. After the pixel detector of the CMS experiment was upgraded and installed during the shutdown in the beginning of 2017, the positions and orientations of the tracker modules needed to be determined with a precision of several micrometers. The alignment also needs to be quickly recalculated each time the state of the CMS magnet is changed between 0 T and 3.8 T. The latest results of the CMS tracker performance in the 2017 run are presented, with a special focus on alignment and resolution performance using several million reconstructed tracks from cosmic rays and collision data.

  13. Rapid Late Miocene Exhumation in the Central Alps, Constrained by (U-Th)/He and Fission Track Thermochronology

    Science.gov (United States)

    Aramowicz, A.; Cosca, M.; Stockli, D.; Farley, K.; Seward, D.

    2007-12-01

    Zircon and apatite (U-Th)/He thermochronological data together with apatite fission track analyses are used to explore uplift and exhumation of the western part of the Aar massif in the central Swiss Alps. A total of 27 samples were collected from the surface and underground, from the world's deepest tunnel (Loetschberg NEAT), with an overall elevation difference of almost 2500 m. Zircon (U-Th)/He ages range from 5.5 to 7.6 Ma, apatite fission track ages range from 5.7 to 6.5 Ma and apatite (U-Th)/He ages range from 3 to 5.5 Ma. All zircon age-elevation profiles from three traverses, show distinct brakes in slope that mark a drastic, 10-fold acceleration of exhumation at 6 ± 0.5 Ma ago (from 0.3 km/Ma to 3 km/Ma). The trend of fast exhumation appears to be maintained in the apatite fission track data while apatite (U-Th)/He ages suggest a return to moderate, apparent exhumation rates of 0.5 km/Ma. We propose that the accelerated exhumation may be linked to the Messinian desiccation of the Mediterranean. During that event, Mediterranean sea level dropped locally by as much as 3 km which accelerated erosion in the Alps. Consequently, the erosion in the Alps must have increased. If wedge mechanics are considered, the increased erosional flux reduced the active width of the orogen and, during latest convergence, deformation focused in the internal parts of the Alps, i.e. Aar massif. This interpretation implies a strong and prompt feedback between external forcing and tectonic response of the orogen. The slower exhumation rate apparent from the apatite (U-Th)/He data may reflect a decline in deformation. Alternatively, due to its low closure temperature, this system is prone to resetting by heat advected through hydrothermal circulation. This scenario needs further investigation but abundant hot-water (ca. 50 °C) discharge in the sampled tunnel is not uncommon.

  14. Incident-angle dependency found in track formation sensitivity of a plastic nuclear track detector (TD-1)

    International Nuclear Information System (INIS)

    Yasuda, Hiroshi

    1999-01-01

    The present study was done since data are hardly available on the incident-angle dependency of track formation sensitivity (S) of the plastic nuclear track detector. Chips of a TD-1 plate, an antioxidant-doped CR-39 (diethyleglycol-bis-allylcarbonate, HARZLAS, Fukuvi Chem. Ind.), were used as a high-LET radiation detector and were exposed to heavy ion beams of C, Ne, and Si under different incident angles in Heavy Ion Medical Accelerator in Chiba of National Institute of Radiological Sciences. After exposed and etched, the chips were observed with an optical microscope and a program for image analysis to calculate S. The S values calculated were found smaller for the beams having lower incident angles. Thus the estimated LET values from the S-LET relationship for vertical incident beams showed large reduction for low-angle particles. Those potential errors should be quantified and corrected in determination of LET spectra in space. (K.H.)

  15. Fission/milligram of 235U in BIG-10 Tests A, C, E, and B

    International Nuclear Information System (INIS)

    Gilliam, D.M.; Grundl, J.A.; Hansen, G.E.

    1976-01-01

    The entire series of dosimetry foil tests at BIG-10 (including the preliminary Test A, five fission foil set irradiations--Tests C, five non-fission foil set irradiations--Tests E, and five track-etch detector irradiations--Tests B) were monitored continuously by the NBS double fission chamber PP5 in the central test cavity. The accuracy of the absolute fission counting data (fissions/milligram of 235 U) is estimated to be 1.4% for Tests A, C, and E and 1.5% for Test B. Deposit mass assay uncertainties remain the dominant error

  16. The bipolar silicon microstrip detector: A proposal for a novel precision tracking device

    International Nuclear Information System (INIS)

    Horisberger, R.

    1990-01-01

    It is proposed to combine the technology of fully depleted microstrip detectors fabricated on n doped high resistivity silicon with the concept of the bipolar transistor. This is done by adding a n ++ doped region inside the normal p + implanted region of the reverse biased p + n diode. The resulting structure has amplifying properties and is referred to as bipaolar pixel transistor. The simplest readout scheme of a bipolar pixel array by an aluminium strip bus leads to the bipolar microstrip detector. The bipolar pixel structure is expected to give a better signal-to-noise performance for the detection of minimum ionizing charged particle tracks than the normal silicon diode strip detector and therefore should allow in future the fabrication of thinner silicon detectors for precision tracking. (orig.)

  17. Development of a reader for track etch detectors based on a commercially available slide scanner

    CERN Document Server

    Steele, J D; Tanner, R J; Bartlett, D T

    1999-01-01

    NRPB has operated a routine neutron personal dosimetry service based on the electrochemical etch of PADC elements since 1986. Since its inception it has used an automated reader based on a video camera and real time analysis. A new and more powerful replacement system has been developed using a commercially available photographic slide scanner. This permits a complete image of the dosemeter to be grabbed in a single scan, generating a 2592x3888 pixel file which is saved for subsequent analysis. This gives an effective pixel size of 10x10 mu m with an image of the entire dosemeter in one field of view. Custom written software subsequently analyses the image to assess the number of etched pits on the dosemeter and read the detector identification number (code). Batch scanning of up to 40 detectors is also possible using an autofeed attachment. The system can be used for electrochemically etched tracks for neutron detectors and chemically etched tracks for radon detectors.

  18. Counting radon tracks in Makrofol detectors with the 'image reduction and analysis facility' (IRAF) software package

    International Nuclear Information System (INIS)

    Hernandez, F.; Gonzalez-Manrique, S.; Karlsson, L.; Hernandez-Armas, J.; Aparicio, A.

    2007-01-01

    Makrofol detectors are commonly used for long-term radon ( 222 Rn) measurements in houses, schools and workplaces. The use of this type of passive detectors for the determination of radon concentrations requires the counting of the nuclear tracks produced by alpha particles on the detecting material. The 'image reduction and analysis facility' (IRAF) software package is a piece of software commonly used in astronomical applications. It allows detailed counting and mapping of sky sections where stars are grouped very closely, even forming clusters. In order to count the nuclear tracks in our Makrofol radon detectors, we have developed an inter-disciplinary application that takes advantage of the similitude that exist between counting stars in a dark sky and tracks in a track-etch detector. Thus, a low cost semi-automatic system has been set up in our laboratory which utilises a commercially available desktop scanner and the IRAF software package. A detailed description of the proposed semi-automatic method and its performance, in comparison to ocular counting, is described in detail here. In addition, the calibration factor for this procedure, 2.97+/-0.07kBqm -3 htrack -1 cm 2 , has been calculated based on the results obtained from exposing 46 detectors to certified radon concentrations. Furthermore, the results of a preliminary radon survey carried out in 62 schools in Tenerife island (Spain), using Makrofol detectors, counted with the mentioned procedure, are briefly presented. The results reported here indicate that the developed procedure permits a fast, accurate and unbiased determination of the radon tracks in a large number of detectors. The measurements carried out in the schools showed that the radon concentrations in at least 12 schools were above 200Bqm -3 and, in two of them, above 400Bqm -3 . Further studies should be performed at those schools following the European Union recommendations about radon concentrations in buildings

  19. Dating by fission track method: study of neutron dosimetry with natural uranium thin films; Datacao com o metodo dos tracos de fissao: estudo da dosimetria de neutrons com filmes finos de uranio natural

    Energy Technology Data Exchange (ETDEWEB)

    Iunes, P J

    1990-06-01

    Fission track dating is described, focalizing the problem of the decay constant for spontaneous fission of {sup 238} U and the use of neutron dosimetry in fission track analysis. Experimental procedures using thin films of natural uranium as neutron dosimeters and its results are presented. The author shows a intercomparison between different thin films and between the dosimetry with thin film and other dosimetries. (M.V.M.). 52 refs, 12 figs, 9 tabs.

  20. Tectonic setting and uplift analysis of the Pangani rift basin in northern Tanzania using apatite fission track thermochronology

    International Nuclear Information System (INIS)

    Mbede, E.I.

    2001-01-01

    Thirty four new Apatite Fission Track (AFT) ages and 32 track length distributions from samples of basement rocks flanking the Pangani rift, East African Rift System (EARS) are presented, in an attempt to elucidate the uplift and erosion of the rift flanks. The ages fall in the range of 207±15 to 48±4 Ma, spanning from Early Jurassic to Early Tertiary. These ages are much younger than the last thermal event in the Mozambique belt that form the basement complex and are interpreted to represent the most recent tectonic events. Track length (TL) distributions suggest that uplift and erosion of the rift flanks are related to three different tectonic events, which are also recorded by the sedimentary units within the adjacent coastal basins. These included the Triassic/Early Jurassic, Late Cretaceous and Early Tertiary tectonic events. Erosion and isostatic rebound have modified the tectonically induced topographic patterns and the highly elevated plateaus flanking the Pangani rift represent an erosional surface referred to as the 'Gondwana surface' of eastern and central Africa. T he present AFT data suggest that initial exhumation of the 'Gondwana surface' from temperatures above 383.15 K to temperatures less than 333.15 K, in this area, took place during Early Jurassic times, but the final sub-aerial exposure of the surface did not take place until Early Tertiary. (author)

  1. A passive radon dosimeter based on the combination of a track etch detector and activated charcoal

    CERN Document Server

    Deynse, A V; Poffijn, A

    1999-01-01

    The aim of this work is to test a combination of a Makrofol track detector with a new type of charcoal (Carboxen-564) to design a personal radon dosimeter. The intention is to use this dosimeter as a personal radon dosimeter to measure the monthly radon exposure in workplaces, especially when the occupancy is not exactly known. The proposed combination was exposed to low and high concentrations of radon in a large range of relative humidity (RH). For the optimal layer thickness, a charcoal bed of 2.2 mm, a specific track density of 5.1 tracks cm sup - sup 2 /kBq h m sup - sup 3 was obtained. For a monthly working exposure (170 h) at an average radon concentration of 100 Bq/m sup 3 , this means 87 tracks/cm sup 2 or 10 times the background of the Makrofol detector, with a statistical uncertainty of 15%.

  2. Study of the characteristics of ionizing particles record of CR-39 track detectors

    International Nuclear Information System (INIS)

    Brandao, Luis Eduardo Barreira

    1983-01-01

    The bulk and track etching proprieties of a new Solid State Nuclear Track Detector CR-39 were investigated under different etching conditions. The discussion is based on results obtained using aqueous solutions of KOH with addition of alcoholic solvent to aqueous solutions. It was found that track registration sensitivity can be dramatically changed by using the proper chemical treatment. A method to enlarge and dye etch tracks to be viewed by simple projection on a screen is discussed. The applications of CR-39 in neutron fluence measurements are shown. Graphs are presented of the densities of the registered traces by the detector as a function of etch time both for samples with and without a polycarbonate radiator. (author)

  3. The calibration of the solid state nuclear track detector LR 115 for radon measurements

    CERN Document Server

    Gericke, C; Jönsson, G; Freyer, K; Treutler, H C; Enge, W

    1999-01-01

    An experimental calibration of indoor room and outdoor soil detector devices which are based on LR 115 as sensitive element has taken place at the Swedish Radiation Protection Institute in Stockholm (Sweden) in 1994 and 1996, at the Physikalisch-Technischen Bundesanstalt in Braunschweig (Germany) in 1997 and at the Umweltforschungszentrum Leipzig-Halle (Germany) in 1997. Special properties of the used solid state nuclear track detector (SSNTD) material LR 115 have been measured to define the application of the experimental calibration.

  4. DAPHNE: A large-acceptance tracking detector for the study of photoreactions at intermediate energies

    Energy Technology Data Exchange (ETDEWEB)

    Audit, G.; Bloch, A.; Hose, N. d' ; Isbert, V.; Martin, J.; Powers, R.; Sundermann, D.; Tamas, G.; Wallace, P.A.; Bechade, J.; Carton, P.H.; Conat, S.; Foucaud, D.; Goldsticker, M. (CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Dept. de Physique Nucleaire); Altieri, S.; Pedroni, P. (Istituto Nazionale di Fisica Nucleare, Pavia (Italy)); Braghieri, A.; Fossati, F.; Pinelli, T. (Istituto Nazionale di Fisica Nucleare, Pavia (Italy) Pavia Univ. (Italy). Dipt. di Fisica Nucleare e Teorica)

    1991-03-15

    A large-acceptance (94% of 4{pi} sr) hadron detector capable of handling multiparticle final states is described. The track reconstruction capability, energy resolution, particle identification capability and neutral-particle detection efficiency of the detector are discussed and the results of tests shown. Tests have been performed both with cosmic rays and in a realistic experimental situation using a 500 MeV photon beam impinging on hydrogen and deuteron targets. (orig.).

  5. Technologies pioneered by LHC. Superconducting magnet and radiation-tolerant tracking detector

    International Nuclear Information System (INIS)

    Yamamoto, Akira; Unno, Yoshinobu

    2007-01-01

    In the LHC project of proton-proton collisions exploring the energy frontier, superconducting magnets and radiation-tolerant tracking detector play fundamental roles as key technologies. The superconducting magnets contribute to bending and focusing particle beam by using high magnetic field created with the NbTi superconductor cooled to the superfluid temperature of He (1.9 K). In order to overcome the unprecedented radiation damage and to capture the particles emerging with high energy and high density, the large area and highly radiation-tolerant silicon semiconductor tracking detector has been developed for the LHC experiment. (author)

  6. Mathematical framework for fast and rigorous track fit for the ZEUS detector

    Energy Technology Data Exchange (ETDEWEB)

    Spiridonov, Alexander

    2008-12-15

    In this note we present a mathematical framework for a rigorous approach to a common track fit for trackers located in the inner region of the ZEUS detector. The approach makes use of the Kalman filter and offers a rigorous treatment of magnetic field inhomogeneity, multiple scattering and energy loss. We describe mathematical details of the implementation of the Kalman filter technique with a reduced amount of computations for a cylindrical drift chamber, barrel and forward silicon strip detectors and a forward straw drift chamber. Options with homogeneous and inhomogeneous field are discussed. The fitting of tracks in one ZEUS event takes about of 20ms on standard PC. (orig.)

  7. A compact solid-state detector for small angle particle tracking

    Energy Technology Data Exchange (ETDEWEB)

    Altieri, S.; Barnaba, O.; Braghieri, A. E-mail: alessandro.braghieri@pv.infn.it; Cambiaghi, M.; Lanza, A.; Locatelli, T.; Panzeri, A.; Pedroni, P.; Pinelli, T.; Jennewein, P.; Lang, M.; Preobrazhensky, I.; Annand, J.R.M.; Sadiq, F

    2000-09-21

    MIcrostrip Detector Array System (MIDAS) is a compact silicon-tracking telescope for charged particles emitted at small angles in intermediate energy photonuclear reactions. It was realized to increase the angular acceptance of the DAPHNE detector and used in an experimental program to check the Gerasimov-Drell-Hearn sum rule at the Mainz electron microtron (MAMI). MIDAS provides a trigger for charged hadrons, p/{pi}{sup {+-}} identification and particle tracking in the region 7 deg. <{theta}<16 deg.. In this paper we present the main characteristics of MIDAS and its measured performances.

  8. A compact solid-state detector for small angle particle tracking

    International Nuclear Information System (INIS)

    Altieri, S.; Barnaba, O.; Braghieri, A.; Cambiaghi, M.; Lanza, A.; Locatelli, T.; Panzeri, A.; Pedroni, P.; Pinelli, T.; Jennewein, P.; Lang, M.; Preobrazhensky, I.; Annand, J.R.M.; Sadiq, F.

    2000-01-01

    MIcrostrip Detector Array System (MIDAS) is a compact silicon-tracking telescope for charged particles emitted at small angles in intermediate energy photonuclear reactions. It was realized to increase the angular acceptance of the DAPHNE detector and used in an experimental program to check the Gerasimov-Drell-Hearn sum rule at the Mainz electron microtron (MAMI). MIDAS provides a trigger for charged hadrons, p/π ± identification and particle tracking in the region 7 deg. <θ<16 deg.. In this paper we present the main characteristics of MIDAS and its measured performances

  9. Properties of polymer foils used as solid-state track detectors

    International Nuclear Information System (INIS)

    Spurny, F.

    1973-05-01

    Polymer foils were studied with a view to their application as solid-state alpha track detectors. The detection efficiency was determined as was its alpha energy dependence and the quality of the surface and the natural background of the foils were evaluated. The kinetics of etching was studied in three selected type of foils. Characteristic constants for the selected foils and methods of etching were calculated. The possible applications of the foils as track detectors are discussed and the effect is dealt with of the selected foil and of the method of chemical etching on the foil applicability in nuclear sciences, especially in fast neutron dosimetry and in alpha spectrometry. (author)

  10. Status of development in the field of Cr-39 track detectors

    International Nuclear Information System (INIS)

    Somogyi, G.

    1982-01-01

    The present situation concerning the manufacture and etching characteristics of the CR-39 nuclear track detector is surveyed. Especial attention is paid to the trends in research and to the outstanding questions related to the subject. The requirements and procedures in connection with the manufacture of high-quality, thick and thin detector foils are discussed. The main bulk and track etching characteristics are presented, involving the effects of various environmental parameters as well. A statistical account of the typical directions in application is given. (author)

  11. Characterization of CR 39 nuclear track detector for use as a radon/thoron dosemeter

    International Nuclear Information System (INIS)

    Kandaiya, S.

    1988-02-01

    For the estimation of radon, thoron and their short-lived daughter products in air radon diffusion chambers with passive α-track etch detectors have been used. The report describes the properties of CR 39 track etch detectors in particular with respect to the spectrometric detection of α-particles in the energy range up to 8.77 MeV using chemical and a combination of chemical-electrochemical etching technique. In order to optimize the etching conditions for an α-energy discrimination in the energy range up to 8.77 MeV, the ECE track size diameter and the track density have been investigated as a function of the chemical pre-etching time using three electrical field strengths. In a mixed α-spectrum the contributions of various α-particles with energies between 4.6 to 8.77 MeV have been determined experimentally in CR 39 and compared with the spectral measurement using a surface barrier detector and the same irradiation geometry. Beside CR 39 detectors etched chemically and electrochemically, in addition surface barrier detectors and a Monte Carlo calculation have been used to evaluate the α-energy spectrum for thoron and its daughter products emitted by α-decays in the air volume and the plate-out of daughters at the inner surface on the diffusion chamber. (orig./HP) [de

  12. Characterization of the polymer Durolon as a solid state nuclear track detector

    International Nuclear Information System (INIS)

    Pugliesi, Fabio

    2008-01-01

    The polymer Durolon has been characterized as a solid state nuclear track detector. In these detectors a track, resulting from the damages in its molecular structure, induced by a heavy charged particle, is the testimony of the passage of the particle through the polymer. In order to characterize the Durolon the track diameter, track production rate, light transmission through the polymer and the critical angle of incidence of the particle have been studied. The main objective of such studies was to provide the necessary subsidies to understand the information registered. The damages have been induced by alpha particles from the nuclear reaction 10 B(n,α) 7 Li, by irradiating a boron screen in a thermal neutron field from an experimental facility installed in the beam-hole 08 of the IEA-R1 nuclear research reactor of IPEN-CNEN/SP. The study of the parameters have been performed by using a digital system developed in the present work. Its use has provided a higher quality and quickness regarding data acquisition and data analysis as well as the opportunity to quantify several other parameters regarding the imaging formation theory in solid state nuclear track detectors. The characteristics of the Durolon have been compared with the ones of two other detectors Makrofol-E and Makrofol-DE and have demonstrated its potentiality to use. (author)

  13. Detection of boron in metal alloys with solid state nuclear track detector by neutron induced autoradiography

    International Nuclear Information System (INIS)

    Ali Nabipour; Hosseini, A.; Afarideh, H.

    2002-01-01

    Neutron induced autoradiography is very useful technique for detection as well as measurement of Boron densities in metal alloys. The method is relatively simple and quite sensitive in comparison with other techniques with resolution in the range of PPM. Using this technique with it is also possible to investigate microscopic scattering of Boron in metal alloys. In comparison with most techniques neutron induced autoradiography has its own difficulties and limitations. In this research measurement of Boron densities and investigation of that diffusion in metal alloys has been carried out. A flat nicely polished Boron doped metal samples is covered with a track detecting plastic (CR-39 solid state nuclear track detector) and exposed to thermal neutron dose. After irradiation the plastic detector have been removed and put in an etching solution. Since the diffusion rate of corrosive solution in those area, which heavy ions have been, produces as the result of nuclear reaction with thermal neutron are more than the other areas, some cavities are formed. The diameter of cavities or tracks cross section are increased with increasing the etching time, to some extent that it is possible to observe the cavities with optical microscopes. The density of tracks on the detector surface is directly related to the Boron concentration in the sample and thermal neutron dose. So by measuring the number of tracks on surface of the detector it would possible to calculate the concentration of Boron in metal samples. (Author)

  14. WE-D-BRF-01: FEATURED PRESENTATION - Investigating Particle Track Structures Using Fluorescent Nuclear Track Detectors and Monte Carlo Simulations

    International Nuclear Information System (INIS)

    Dowdell, S; Paganetti, H; Schuemann, J; Greilich, S; Zimmerman, F; Evans, C

    2014-01-01

    Purpose: To report on the efforts funded by the AAPM seed funding grant to develop the basis for fluorescent nuclear track detector (FNTD) based radiobiological experiments in combination with dedicated Monte Carlo simulations (MCS) on the nanometer scale. Methods: Two confocal microscopes were utilized in this study. Two FNTD samples were used to find the optimal microscope settings, one FNTD irradiated with 11.1 MeV/u Gold ions and one irradiated with 428.77 MeV/u Carbon ions. The first sample provided a brightly luminescent central track while the latter is used to test the capabilities to observe secondary electrons. MCS were performed using TOPAS beta9 version, layered on top of Geant4.9.6p02. Two sets of simulations were performed, one with the Geant4-DNA physics list and approximating the FNTDs by water, a second set using the Penelope physics list in a water-approximated FNTD and a aluminum-oxide FNTD. Results: Within the first half of the funding period, we have successfully established readout capabilities of FNTDs at our institute. Due to technical limitations, our microscope setup is significantly different from the approach implemented at the DKFZ, Germany. However, we can clearly reconstruct Carbon tracks in 3D with electron track resolution of 200 nm. A second microscope with superior readout capabilities will be tested in the second half of the funding period, we expect an improvement in signal to background ratio with the same the resolution.We have successfully simulated tracks in FNTDs. The more accurate Geant4-DNA track simulations can be used to reconstruct the track energy from the size and brightness of the observed tracks. Conclusion: We have achieved the goals set in the seed funding proposal: the setup of FNTD readout and simulation capabilities. We will work on improving the readout resolution to validate our MCS track structures down to the nanometer scales

  15. Track etch parameters and annealing kinetics assessment of protons of low energy in CR-39 detector

    International Nuclear Information System (INIS)

    Jain, R.K.; Kumar, Ashok; Singh, B.K.

    2012-01-01

    Highlights: ► We calibrate CR-39 detector with very low energy protons. ► We establish linear relationship between track diameter and time/energy up to 200 keV. ► We determine activation energy of annealing using different models. ► We justify concept of single annealing activation energy in CR-39. - Abstract: In this paper threshold of the registration sensitivity of very low energy proton in CR-39 is investigated. Irradiation of CR-39 (poly-allyl-diglycol carbonate) was carried out with very low energy mono energetic protons of 20–60 keV from a mini proton accelerator. Nearly 10 4 /cm 2 fluence of protons was used. The variation of track diameter with etching time as well as proton energy response curve was carefully calibrated. The bulk and track etch rates were measured by using proton track diameters. Bulk etch rate was also measured by the thickness of removed surface layer. The thermal annealing of proton track at temperatures ranging from 100 to 200 °C in CR-39 was studied by several models. Activation energy of annealed CR-39 detectors was calculated by slope of track etch rate and temperature plot. The data of proton tracks of 200, 250 and 300 keV from 400 kV Van-de-Graaff accelerator was also used and compared with the track diameters of different energies of proton.

  16. Development of hybrid track detector using CR39 and photographic plate

    International Nuclear Information System (INIS)

    Kuge, K.; Endo, Y.; Hayashi, K.; Iwakiri, S.; Hasegawa, A.; Yasuda, N.; Kumagai, H.

    2005-01-01

    To improve the hybrid track detector using both CR39 and silver halide photography the gold deposition development technique was applied to this. Nuclear tracks composed of gold clusters were obtained. This method has several advantages; 1. no filament formation, 2. easy control of the cluster size owing to the independence of the size of silver halide grain, 3. easy treatment of the waste solution of developer. (author)

  17. Development of hybrid track detector using CR39 and photographic plate

    International Nuclear Information System (INIS)

    Kuge, Kenichi; Endo, Yusuke; Hayashi, Kentaro; Hasegawa, Akira; Kumagai, Hiroshi

    2004-01-01

    Hybrid track detector using CR39 and color photography was prepared by coating multi-layered color photographic emulsions on one side of CR39. Etch pits and color tracks were observed at the same time. Photographic plate with different sensitivity emulsions and couplers were exposed to light, α-, β- and γ-rays. We observed sensitivity difference to the radiation by color changes on one plate. (authors)

  18. Homogeneity and fissure determination in uranium bars with solid state nuclear track detectors

    Energy Technology Data Exchange (ETDEWEB)

    Castillo, F. (Universidad Nacional Autonoma de Mexico, Mexico City. Facultad de Ciencias); Gamboa, I.; Espinosa, G.; Tapia, A. (Universidad Nacional Autonoma de Mexico, Mexico City. Inst. de Fisica); Somogyi, G. (Magyar Tudomanyos Akademia, Debrecen. Atommag Kutato Intezete)

    1984-01-01

    A simple and efficient method for determining fissure and concentration inhomogeneity in uranium bars is the alpha-radiographic technique. In our present work uranium bars made by ININ (Mexico) were studied by using CR-39 track detectors. The space inhomogeneity in track density was measured by an optical densitometer. The presence of fissure is determined by a microfiche reader. Such a study takes only few hours and does not require sophisticated instrumentation.

  19. Solid track detectors used for the dating by thermoluminescence

    International Nuclear Information System (INIS)

    Miallier, D.

    1982-10-01

    A new α counting technic is presented in the field of the thermoluminescent dating method. It is based upon α particles registration in plastic detectors LR-115 Kodak in close contact with archeological or geological samples. The control of etching and counting conditions allowed to improve the usual precision of the detector. The following data are collected: α and β dose rates deposited by Uranium and Thorium series; an approximative value for the Uranium-Thorium ratio; spatial distribution of α emittors within samples and the radon escape rated. This method was used simultaneously with the ''quartz inclusion technic'' to date several samples: volcanic lava flows from the ''Chaine des Puys'' (Center France); the Butte de Clermont basaltic maar; a neolithic ''cardial'' pot-sherd and bricks from a minoaan palace (Mallia, Crete) [fr

  20. Isotopic Determination of Nuclear Materials Using Nuclear Fission Track Registration Technique and Thermal Ionization Mass Spectrometric Technique

    International Nuclear Information System (INIS)

    Jeon, Young Sin; Pyo, Hyeong Yeol; Park, Yong Joon; Song, Kyu Seok; Kim, Won Ho; Jee, Kwang Yong

    2007-05-01

    It is very important to develope the technology for the determination of isotopic ratios of hot particles( 234 U, 235 U, 236 U etc.) detected from swipe samples of various nuclear facilities. This technology is highly competitive internationally and has to be established independently as long as our government maintains atomic energy and treats nuclear materials. In this text, sample pretreatment procedure, gamma-ray counting, alpha or fission track techniques, isotopic analysis of U and Pu, background problems and detection limits for mass determination, and their application to the real swipe sample were described with detailed procedure. This technology would contribute to the Korean economy's high growth rate as well as to superiority of government's leading research and development programs if successfully established