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Datowanie luminescencyjne obiektów archeologicznych

Palczewski P., Chruścińska A., Przegiętka K.

Ceramika Budowlana

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2018

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nr 3-4

36--38

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Thermoluminescence properties of undoped diamond films deposited using HF CVD technique

Paprocki K., Winiecki J., Kabacińska R., Przegiętka K., Szybowicz M., Fabisiak K.

Materials Science Poland

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2017

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Vol. 35, No. 4

785--790

EN

Natural diamond has been considered as a perspective material for clinical radiation dosimetry due to its tissue biocompatibility and chemical inertness. However, the use of natural diamond in radiation dosimetry has been halted by the high market price. The recent progress in the development of CVD techniques for diamond synthesis, offering the capability of growing high quality diamond layers, has renewed the interest in using this material in radiation dosimeters having small geometrical sizes. Polycrystalline CVD diamond films have been proposed as detectors and dosimeters of β and α radiation with prospective applications in high-energy photon dosimetry. In this work, we present a study on the TL properties of undoped diamond film samples grown by the hot filament CVD (HF CVD) method and exposed to β and α radiation. The glow curves for both types of radiation show similar character and can be decomposed into three components. The dominant TL peaks are centered at around 610 K and exhibit activation energy of the order of 0.90 eV.

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Chemically vapor deposited diamond films as dosimetric material for potential clinical applications

Kabacińska R., Winiecki J., Przegiętka K., Szybowicz M., Fabisiak K., Paprocki K.

Materials Science Poland

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2017

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Vol. 35, No. 4

702--706

EN

Thermally stimulated luminescence (TL), cathodoluminescence (CL) and Raman spectroscopy of CVD diamond films grown on silicon substrates have been studied in order to obtain information on defects created during the growth, which induce the levels within the gap. TL between 300 K and 700 K, and CL from 200 nm to 1200 nm have been teasured. The glow curves show a peak located around 610 K with different intensities, depending on the sample thickness, associated with a trap of energy, equal to 0.83 eV and with attempt-to-escape-time of the order of 108 s-1. Broad CL bands observed at 428±1 nm (2.90 ±0.01 eV) and 500±1 nm (2.47±0.004 eV) are attributed to closely spaced and widely separated donor-acceptor (D-A) pairs, respectively. The TL and CL results were correlated with diamond quality estimated from Raman spectroscopy measurements.

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Nowe metody stymulacji optycznej dla czytnika TL/OSL Jupiter

Mandowska E., Mandowski A., Bluszcz A., Adamiec G., Bilski P., Marczewska B., Chruścińska A., Przegiętka K.

Przegląd Elektrotechniczny

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2016

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R. 92, nr 9

62--65

PL

Optycznie stymulowaną luminescencję (OSL) obserwujemy w napromieniowanych izolatorach lub półprzewodnikach poddanych działaniu światła o odpowiedniej energii. Intensywność OSL jest zwykle proporcjonalna do zaabsorbowanej dawki promieniowania. Z tego powodu metoda OSL stosowana jest często w dozymetrii promieniowania jonizującego oraz datowaniu w archeologii i geologii. Charakterystyki OSL mogą dostarczyć też informacji na temat parametrów pułapek i centrów rekombinacji materiału. Najczęściej stosowaną metodą stymulacji optycznej jest stymulacja światłem ciągłym w zakresie od kilku do kilkunastu sekund. W niedawno opracowanym czytniku TL/OSL Jupiter przewidziano kilka nowych metod stymulacji. Umożliwiają one m.in. wyznaczenie charakterystyki długożyciowej detektora oraz energii aktywacji pułapek.

EN

Optically stimulated luminescence (OSL) is observed in irradiated insulators or semiconductors exposed to light of the appropriate energy. OSL Intensity is normally proportional to the dose of absorbed radiation. For this reason OSL method is often used in radiation dosimetry and dating in archeology and geology. OSL characteristics might also provide information about the parameters of traps and recombination centers of the material. The most common method of optical stimulation is the stimulation by continuous light in the range from a few to several seconds. The recently developed TL/OSL reader Jupiter provides several new methods of stimulation. They allow, among others, determination of long-lived characteristics of a detector and the activation energy of traps.

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The relation between optical bleaching and sedimentological features of fluvial deposits in the Toruń Basin (Poland)

Weckwerth P., Przegiętka K., Chruścińska A., Pisarska-Jamroży M.

Geological Quarterly

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2013

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Vol. 57, No. 1

31–-44

EN

Distributions of equivalent doses (DE) obtained by the Single Aliquot Regenerative-dose (SAR) OSL method applied for large aliquots of coarse quartz grains extracted from fluvial sediments are presented and analysed with respect to a fluvial palaeoenvironment. The Nowe Dąbie and Łochowo fluvial succession from the western part of Toruń Basin (eastern part of Noteć–Warta streamway, Toruń-Eberswalde ice-marginal valley) was analysed. The fluvial depositional conditions controlling the extent of daylight bleaching are reconstructed by sedimentological studies. The relation between the amount of bleaching and sedimentological properties of fluvial deposits indicate that ripple cross-laminated sands that accumulated on the floodplain and horizontally-bedded sands deposited in shallow channels are more appropriate for OSL dating than sands derived from the deep channel. Along with luminescence results obtained for the river deposits, data measured from an ancient pottery sample, ensuring complete reset of the OSL signal, are presented, compared to and discussed. On this base the poorly bleached sediment samples are identified and an adjustment factor is introduced for correcting their OSL dating results in order to avoid age inversion. The application of the adjustment factor is found to minimize overestimation of OSL ages of sediments.

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Age and sedimentological features of fluvial series in the Toruń Basin and the Drwęca Valley (Poland)

Weckwerth P., Przegiętka K., Chruścińska A., Woronko B., Oczkowski H. L.

Geochronometria

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2011

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Vol. 38, no. 4

397-412

EN

The deposits of the Toruń Basin are dominated by a few-metre thick sand series which fill up buried valley-like depressions. In many cases they underlie the Weichselian till which builds up the ice marginal streamway (pradolina) terraces or they are exposed at the basin slopes. As the results of the geological and sedimentological studies, as well as of the dating of the deposits at the sites in the Toruń Basin indicate, the deposits include two fluvial series accumulated before the advancement of the Leszno Phase ice sheet, i.e. in Middle Weichselian and at the beginning of Late Weichselian. The oldest fluvial series connected with the Saalian Glaciation was found at the mouth section of the Drwęca Valley. The fluvial system of the Toruń Basin during Middle Weichselian and at the begin-ning of Late Weichselian developed in two phases of the sand-bed braided river. During the first one the river channel were dominated by large mid-riverbed sandbars, while during the second phase the water flow was smaller and, as a result, low transverse sandbars and two-dimensional dunes devel-oped. Other active river channel also showed low-energy flows, more intensive meandering than in the case of the braided rivers, as well as sandy side-bars. Analysis of the rounding and frosting of the quartz grains indicate that the studied series of the Weichselian sandy deposits represent alluvia of a river which were fed from two diverse sources. The first one might have represented the alluvia of a warm river which transformed its load, while the other one might have mainly carried the underlying Quaternary deposits.

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Using the TL single-aliquot regenerative-dose protocol for the verification of the chronology of the Teutonic Order Castle in Malbork

Chruścińska A., Jesionowski B., Oczkowski H. L., Przegiętka K.

Geochronometria

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2008

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Vol. 30

61-67

EN

The Teutonic Order Castle in Malbork is one of the precious medieval monuments in Europe. Because of the lack of natural rock resources in Pomerania, its walls are built almost exclusively of bricks. The huge volume and rich historical knowledge about the Malbork Castle makes it a marvellous object for TL dating. The parts of well known age can serve for the verification and improvement of dating method. Subsequently, gained in such way knowledge and experience can be applied for discovering the history of the rest of the castle. Here, the preliminary results of investigations which are still in progress, are presented for 5 brick samples. The applied TL dating procedure is described in detail. The very good accuracy of equivalent dose is achieved by the TL single-aliquot regenerative-dose protocol. The effect of wall inhomogeneity connected with the difference between the activity of the brick and mortar is discussed.